# Phenomenology 2015 Symposium

US/Eastern
University of Pittsburgh

#### University of Pittsburgh

Pittsburgh, PA 15260
Description

The 2015 Phenomenology Symposium will be held May 4-6, 2015 at the University of Pittsburgh.  It will cover the latest topics in particle phenomenology and theory plus related issues in astrophysics and cosmology.

Early registration ends April 12, 2015

Talk submission ends April 19, 2015

Conference banquet May 5, 2015

The plenary program and full program are now available

Tentative plenary topics and speakers:

• Wolfgang Altmannshofer (Perimeter Institute):  Flavor Physics in the New Era
• Howard Baer (Oklahama):  Where is SUSY?
• Tom Browder (Hawaii):  B-Physics: The Next Generation
• Daniel Eisenstein (Harvard CfA):  Physics from DESI
• Christoph Englert (Glasgow):  Higgs Phenomenology
• Jens Erler (UNAM):  The SM after the Higgs Discovery
• Silvia Galli (IAP):  Cosmological Results from Planck 2015
• Ian Hinchliffe (LBNL, ATLAS):  Standard Model Physics at the LHC
• Lam Hui (Columbia):  Symmetries in Cosmology and Large Scale Structure
• Xiangdong Ji (Maryland/SJTU):  Dark Matter Direct Detection
• Greg Landsberg (Brown, CMS):  New Physics Searches at CMS and ATLAS
• Aneesh Manohar (UCSD):  EFT: Theory and Practice
• Shigeki Matsumoto (IPMU):  Physics and Perspectives of the ILC
• Silvia Pascoli (IPPP):  Neutrino and Lepton Theory
• Mayly Sanchez (Iowa State):  Neutrino Physics in the New Era
• Tracy Slatyer (MIT):  Dark Matter: Theory and Searches
• Jesse Thaler (MIT):  Pushing the Frontiers of Perturbative QCD
• James Wells (Michigan):  HEP: Future perspectives

Parallel session mini-reviews:

• Sekhar Chivukula (MSU):  New Resonances: Theory and Searches
• Stefania Gori (Perimeter Institute):  Physics with Electroweakinos
• Ian Lewis (SLAC):  Physics Under the Higgs Lamppost
• Konstantin Matchev (Florida):  Matrix Element Techniques
• Burt Ovrut (U Penn):  Broken B-L Symmetry

PITT PACC Travel Awards: With support from the NSF and DOE, there are a number of awards (up to $300 each) available to domestic graduate students for travel and accommodation to Pheno 15. A student applicant should send an updated CV and a statement of financial need, and arrange for a short recommendation letter sent from their thesis advisor, by email to pittpacc+award@pitt.edu. The decision will be based on the academic qualification, the talk submission to Pheno 15, and the financial need. The deadline for the application is April 5, and the winners will be notified by April 13. (Each research group may be limited to one awardee. Winners in the previous years may have lower priority for consideration. Winner institutes and names will be announced at the Symposium banquet.) PHENO 2015 ORGANIZERS: Cindy Cercone, Ayres Freitas, Tao Han (chair), Adam Leibovich, Josh Sayre, Brock Tweedie, and Susanne Westhoff. PHENO 2015 PROGRAM ADVISORS: Vernon Barger, Lisa Everett, Kaoru Hagiwara, JoAnne Hewett, Arthur Kosowsky, Tilman Plehn, Xerxes Tata, and Andrew Zentner. OTHER ANNOUNCEMENTS DIS2015 will be held on SMU campus in Dallas during 27 April - 1 May, 2015 Baseball game (informal): Pittsburgh Pirates vs Cincinnati Reds, Weds May 6, 7:05 pm. Individuals may purchase tickets on their own if they choose to attend. Support • Monday, May 4 • 7:30 AM Registration & Breakfast Alumni Hall 7th Floor ### Alumni Hall 7th Floor #### University of Pittsburgh Pittsburgh, PA 15260 • Plenary I Alumni Hall 7th Floor Auditorium ### Alumni Hall 7th Floor Auditorium #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Liz Simmons • 1 Welcome • 2 Standard Model Physics at the LHC Speaker: Dr Ian Hinchliffe (Lawrence Berkeley National Lab. (US)) • 3 New Physics Searches at CMS and ATLAS Speaker: Greg Landsberg (Brown University (US)) • 4 Higgs Phenomenology Speaker: Christoph Englert (Heidelberg University) • 10:30 AM Coffee Break Alumni Hall 7th Floor ### Alumni Hall 7th Floor • Plenary II Alumni Hall 7th Floor Auditorium ### Alumni Hall 7th Floor Auditorium #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Tilman Plehn • 5 The Standard Model after the Higgs Discovery Speaker: Jens Erler (IF-UNAM) • 6 Cosmological Results from Planck 2015 Speaker: Silvia Galli • 7 Physics from DESI Speaker: Daniel Eisensten • 12:45 PM Lunch Oakland Area ### Oakland Area • BSM I G27 ### G27 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Natascia Vignaroli (Michigan State University) • 8 Mini-Review: Broken B-L Symmetry Speaker: Prof. Burt Ovrut • 9 Minimal Non-Supersymmetric Unified$SO(10)$Model We present the minimal non-supersymmetric Grand Unified$SO(10)$Model, which is compatible with all the phenomenological constraints. The Higgs sector, containing a real 54-plet, a complex 126-plet and a complex 10-plet breaks the symmetry to Standard Model via Pati-Salam symmetry with D-parity at an intermediate scale consistent with current neutrino data. Threshold correction introduced by the scalar mass spectra pushes the unification scale high enough to accommodate proton lifetime beyond current experimental limit. The model has a Yukawa sector which is compatible with fermion masses-mixing and leptogensis. Enlarging the symmetry to$SO(10) \times U(1)_{PQ}$, we can simultaneously address the strong CP problem and stability of the electroweak vacuum while Axion of the theory becomes Dark matter candidate. Sample points in the parameter space has been produced which can explain all the physics below GUT scale. Speaker: Saki Khan (Oklahoma State University) • 10 SM Hypercharge: from Superconnection to Noncommutative Geometry In this talk, I will show the realization of U(1) hypercharges with two different formalisms, superconnection and noncommutative geometry(NCG). In both cases, the Standard Model hypercharges are derived instead of being assigned. This is a hint for the underlying relation between superconnection formalism and NCG formalism, both of which interpret the Higgs as a gauge field in the discrete direction, and give similar values of the Higgs mass. Possible extensions to left-right symmetric models are also briefly discussed. Speaker: Chen Sun (Virginia Tech) • 11 Mass Reach Scaling for Future Hadron Colliders The primary goal of any future hadron collider is to discover new physics (NP) associated with a high mass scale,$M$, beyond the range of the LHC. In order to maintain the same {\it relative} mass reach for NP,$M/{\sqrt s}$, as$\sqrt s$increases, Richter recently reminded us that the required integrated luminosity obtainable at future hadron colliders (FHC) must grow rapidly,$\sim s$, in the limit of naive scaling. This would imply, \eg, a$\sim 50$-fold increase in the required integrated luminosity when going from the 14 TeV LHC to a FHC with$\sqrt s=100$TeV, an increase that would prove quite challenging on many different fronts. In this paper we point out, due to the scaling violations associated with the evolution of the parton density functions (PDFs) and the running of the strong coupling,$\alpha_s$, that the actual luminosity necessary in order to maintain any fixed value of the relative mass reach is somewhat greater than this scaling result indicates. However, the actual values of the required luminosity scaling are found to be dependent upon the detailed nature of the NP being considered. Here we elucidate this point explicitly by employing several specific benchmark examples of possible NP scenarios and briefly discuss the search impact in each case if these luminosity goals are not met. Speaker: Dr Thomas Rizzo (SLAC) • 12 Hilbert Series for Constructing Lagrangians I will present the basics of the Hilbert series technique in the context of constructing group-invariant Lagrangians. This technique provides a fast way to calculate the number of operators of a specified mass dimension for a given field content, and is a useful cross check on more well-known group theoretical methods. In addition, at least when restricted to invariants without derivatives, the Hilbert series technique supplies a robust way of counting invariants in scenarios which, due to the large number of fields involved or to high dimensional group representations, are intractable by traditional methods. Speaker: Landon Lehman • 13 Stable Asymptotically Free Extensions (SAFEs) of the Standard Model We consider possible extensions of the standard model that are not only completely asymptotically free, but are such that the UV fixed point is completely UV attractive. All couplings flow towards a set of fixed ratios in the UV. Motivated by low scale unification, semi-simple gauge groups with elementary scalars in various representations are explored. The simplest model is a version of the Pati-Salam model. The Higgs boson is truly elementary but dynamical symmetry breaking from strong interactions may be needed at the unification scale. A hierarchy problem, much reduced from grand unified theories, is still in need of a solution. Speaker: Dr Jing Ren (University of Toronto) • 14 Baryon number violation and the dark sector Dark sector states, uncharged under SM gauge interactions, can be invoked to explain neutrino masses or cosmic dark matter. These states may have baryon number violating interactions. We outline some aspects of phenomenology originating from such interactions. Possible signals at nucleon decay experiments or the LHC are discussed. Speaker: Dr Hooman Davoudiasl (BNL) • Cosmology I Convener: Andrew Zentner (University of Pittsburgh) • 15 Cosmological Constraints on the Newtonian Gravitational Constant of Matter and Dark Matter We present new constraints on cosmic variations of Newton's gravitational constant by making use of the latest CMB data from the PLANCK experiment and independent constraints coming from Big Bang Nucleosynthesis and low redshift experiments. Furthermore, while equivalence principle breaking is tightly constrained in the baryonic matter sector, the constraint on dark matter is much weaker. Introducing a new long range fifth force to break the equivalence principle in the dark sector, we use the latest cosmological data to improve this constraint. Speaker: Mr Ben Stefanek (University of Wisconsin Madison) • 16 Synthetic Gravity Waves and the Scale of Inflation We consider whether the presence of additional fields and non-adiabaticity during inflation may have provided an additional source of primordial B-modes competitive with those of the quasi-de Sitter vacuum. In particular, we examine whether the additional sources could provide the dominant signal, which could lead to a misinterpretation of the scale of inflation. Speaker: Ogan Ozsoy (Syracuse University) • 17 Natural Inflation and Quantum Gravity Cosmic inflation can readily involve energies close to the scale at which quantum gravity effects become important. General considerations of black hole quantum mechanics suggest nontrivial constraints on any effective field theory model of inflation that emerges as a low-energy limit of quantum gravity, in particular the constraint of the Weak Gravity Conjecture. We show that higher-dimensional gauge and gravitational dynamics can elegantly satisfy these constraints and lead to a viable, theoretically-controlled and predictive class of natural inflation models. Speaker: Prashant Saraswat (University of Maryland and Johns Hopkins University) • 18 Cosmoligical consequences of Extended Quasidilaton Massive Gravity Quasidilaton massive gravity offers a physically well-defined gravitational theory with non-zero graviton mass. I will discuss the expansion history of the universe in quasidilaton massive gravity models, during radiation domination, matter domination, and a late-time self-accelerating epoch related to the graviton mass, and I will present the comparison of theoretical predictions with the Supernovae data. The existence of self-consistent solutions constrains the amplitude of the quasi-dilaton field and the graviton mass, as well as other model parameters. Additional bounds on model parameters are obtained through the stability of gravitational perturbations. It can be shown that the effective mass of gravitational waves can be significantly larger than the graviton mass, opening the possibility that a single theory can explain both the late-time acceleration of the cosmic expansion and modifications of structure growth leading to the suppression of large-angle correlations observed in the cosmic microwave background. Speaker: Tina Kahniashvili (Carnegie Mellon University) • 19 No-scale Supergravity based inflation models It is well known that no-scale Supergravity models generically lead to the Higgs-inflation or Starobinsky inflation favored by the CMB data. We examine specific particle physics models which are consistent with the no-scale SUGRA boundary conditions. I discuss the restrictions on SO(10) SUSY-GUT model as well as the NMSSM model from no-scale SUGRA which can give a viable Satobinsky inflation. Speaker: Subhendra Mohanty (Physical Research Laboratory) • 20 Examining the Viability of Phantom Dark Energy In the standard cosmological framework of the 0th-order FLRW metric, dark energy as a scalar field with an equation-of-state parameter$w < -1$implies negative kinetic energy and vacuum instability. However, the value of best fit from Planck and WMAP9 for present-day$w$is indeed less than$-1$. We find that it is not as obvious as one might think that phantom dark energy has negative kinetic energy categorically. Staying within the confines of observational constraints and general relativity, for which there is good experimental validation, we consider a few reasonable departures from the standard cosmological framework in an attempt to see if negative kinetic energy can be avoided in these settings despite an apparent$w<-1$. We consider a more accurate description of the universe through the perturbing of the isotropic and homogeneous FLRW metric and the components of the stress-energy tensor, and we also consider dynamic$w$, and primordial isocurvature perturbations. Speaker: Kevin Ludwick (University of Virginia) • 21 How robust are axion isocurvature constraints in high-scale inflation? Axions are a well-motivated candidate to solve the strong CP problem and may also make up the observed dark matter energy density. But if the axion is massless during inflation, it gets fluctuations of order the Hubble parameter, which are later imprinted in the cosmic microwave background (CMB) as isocurvature fluctuations. Near-future experiments will seek to detect primordial gravitational waves imprinted in the tensor modes of the CMB. Any detection would signal that inflation occurred at a high scale. This, along with the present non-detection of isocurvature modes, would then place severe constraints on axion models with Peccei-Quinn breaking scales larger than the Hubble parameter during inflation. I will discuss whether it is possible to alleviate such constraints by generating a large mass for the axion during inflation. Speaker: Nicholas Orlofsky • 22 Expanding the Axion Field Range via Mixings In this talk, we will propose a mechanism to widen the axion field range in theories where the intrinsic axion field range is limited. We will point out that kinetic and Stueckelberg mixings that are generically present in the low energy effective action of axions can significantly widen the window of axion decay constants. We will show that an effective super-Planckian decay constant can be obtained even when the axion kinetic matrix has only sub-Planckian entries. In contrast to previous approaches, the axion field range enhancement is not tied to the number of degrees of freedom in the theory, and thus a 2-axion system with a single U(1) gauge field and a single gauge instanton serves as a minimal setup to achieve a super-Planckian excursion. We will also see a desired axion decay constant within the range of axion dark matter window can be obtained by tuning the continuous parameters that control the amount of mixings. Finally we will briefly discuss how to implement our mechanism in string theory. Speaker: Ms Fang Ye (University of Wisconsin-Madison) • Dark Matter I G29 ### G29 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Can Kilic (University of Texas at Austin) • 23 Chromo-Rayleigh Interactions of Dark Matter We study the collider constraints on chromo-Rayleigh interactions of dark matter. Here we present the results of an effective operator analysis and compare collider and direction detection constraints. For dark matter masses of order 100 GeV the constraints from monojet searches are relatively weak, questioning the applicability of the effective operator description. Thus, we also present several simplified UV completions and find that one such model gives rise to the novel signature of pair-produced dijet resonances with large missing transverse energy. Speaker: James Osborne (University of Wisconsin - Madison) • 24 QCD Effects on Direct Detection of Wino Dark Matter We complete the calculation of the wino-nucleon scattering cross section up to the next-to-leading order in αs. We assume that the other sparticles are decoupled and wino interacts with the Standard Model particles via the weak interaction. As a result, the uncertainties coming from the perturbative QCD are significantly reduced to be smaller than those from the nucleon matrix elements. The resultant scattering cross section is found to be larger than the leading-order one by about 70%, which is well above the neutrino background. Speaker: Dr Natsumi Nagata (University of Minnesota) • 25 Model Independent Approach to Inelastic Dark Matter We present a model independent approach for low-energy scattering of inelastic dark matter. We find the relevant nonrelativistic variables which describe these processes are very similar to the operators discussed by Fitzpatrick *et at* with the modification of the$v^\perp$variable. Taking this into account, we list the relevant matrix elements and modify the *Mathematica* package of Anand *et al* which calculates the nuclear form factors corresponding to specific nuclear responses. Speaker: Chris Newby • 26 Lessons Learned from Model Independent Inelastic Dark Matter Direct Detection As an application of the model independent approach to analyzing inelastic dark matter direct detection, as detailed in arxiv: 1409.0536, I will discuss fits to the DAMA annual modulation signal, and corresponding constraints from other direct detection experiments. It is particularly interesting what this tells us about the sensitivity of constraints to uncertainty in detector characteristics, most notably the quenching factor of iodine. I will also comment on the importance of high energy events in constraining an inelastic dark matter scenario. Speaker: Gregory Barello (University of Oregon) • 27 Modulation Effects in Dark Matter-Electron Scattering Experiments One of the next frontiers in dark-matter direct-detection experiments is to explore the MeV to GeV mass regime. Such light dark matter does not carry enough kinetic energy to produce an observable nuclear recoil, but it can scatter off atomic electrons, ionizing the target atom and leading to a measurable signal. We introduce a semi-analytic approach to characterize the resulting electron-scattering events in atomic and semiconductor targets, improving on previous analytic proposals that underestimate the signal at high recoil energies. We then use this procedure to study the time-dependent properties of the electron-scattering signal, including the modulation fraction, higher-harmonic modes and modulation phase. The time-dependence is distinct in a non-trivial way from the nuclear scattering case and also affected by gravitational focusing due to the Sun. Additionally, we show that dark matter interactions inside the Earth can significantly distort the lab-frame phase-space distribution of sub-GeV dark matter, leading to a daily modulation. Speaker: Siddharth Mishra Sharma (Princeton University (US)) • 28 Strong Optimized Conservative DM Constraints from Fermi-LAT Inclusive Spectrum The Fermi$\gamma$-ray Space Telescope has observed the sky since 2008. Dark matter annihilations or decays contribute to the measured diffuse$\gamma$-ray background flux. Using simulated data to first find the “optimal” regions of interest in the$\gamma$-ray sky, we present conservative bounds on annihilation cross section or decay lifetime competitive with other existing limits. We consider DM annihilation/decay into 10 different SM & BSM final states, 4 DM density profiles, and 2 GeV <$m_{DM}$< 10 TeV, performing no astrophysical foreground modeling. (ArXiv: 1503.07169) Speaker: Andrea Massari (Stony Brook University) • 29 Dark Matter Constraints on Triangles with Indirect Searches In indirect dark matter searches, the current status quo in presenting limits is to quote the simplest assumption of annihilation rates wherein there is one annihilation channel. We will discuss using a triangle based visualization that extends beyond this, allowing for constraints on dark matter mass to be shown for a more realistic assumption of multiple annihilation channels being open. As a demonstration of this visualization technique, we look at results from the Fermi-LAT telescope. Speaker: Colburn Russell (The Ohio State University) • 30 Towards a Bullet-proof test for indirect signals of dark matter Merging galaxy clusters such as the Bullet Cluster provide a powerful testing ground for indirect detection of dark matter. The spatial distribution of the dark matter is both directly measurable through gravitational lensing and substantially different from the distribution of potential astrophysical backgrounds. We propose to use this spatial information to identify the origin of indirect detection signals, and we show that even statistical excesses of a few sigma can be robustly tested for consistency---or inconsistency---with a dark matter source. For example, our methods, combined with already-existing observations of the Coma Cluster, would allow the 3.55 keV line to be tested for compatibility with a dark matter origin. We also discuss the optimal spatial reweighting of photons for indirect detection searches. The current discovery rate of merging galaxy clusters and associated lensing maps strongly motivates deep exposures in these dark matter targets for both current and upcoming indirect detection experiments in the X-ray and gamma-ray bands. [$arXiv:1502.03824$][1] [1]: http://arxiv.org/abs/1502.03824 Speaker: Timothy Wiser (Stanford University) • Higgs I G30 ### G30 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Dr Doojin Kim (University of Florida) • 31 Mini-Review: Physics Under the Higgs Lamppost Speaker: Ian Lewis (SLAC) • 32 CP nature of the top-Higgs interaction at the LHC The discovery of the Higgs boson has now opened a window of opportunity to investigate the possibility of Beyond the Standard Model Physics through scrutiny of the nature of its interactions with other SM particles. In this talk we will focus on the CP nature of the Higgs and top interaction. More specifically, we investigate methods to explore the CP nature of the tth coupling at the LHC, in a model independent way, focusing on associated production of the Higgs with a pair of top quarks. Speaker: Kirtimaan Mohan (Michigan State University) • 33 Higgs characterisation at NLO in QCD: CP properties of the top-quark Yukawa interaction At the LHC the CP properties of the top-quark Yukawa interaction can be probed through Higgs production in gluon fusion or in ttH/tH. We consider the possibility for both CP-even and CP-odd couplings to the top quark to be present, and study CP-sensitive observables at next-to-leading order (NLO) in QCD, including parton-shower effects. Speaker: Kentarou Mawatari (Vrije Univ. Brussel) • 34 Complementarity of LHC and EDMs for Exploring Higgs CP Violation We analyze the constraints on a CP-violating, flavor conserving, two Higgs doublet model from the measurements of Higgs properties and from the search for heavy Higgs bosons at LHC, and show that the stronger limits typically come from the heavy Higgs search channels. The limits on CP violation arising from the Higgs sector measurements are complementary to those from EDM measurements. Combining all current constraints from low energy to colliders, we set generic upper bounds on the CP violating angle which parametrizes the CP odd component in the 126 GeV Higgs boson. Speaker: Chien-Yi Chen (Brookhaven National Laboratory) • 35 Contributions of flavor violating couplings of a Higgs boson to$pp \to WW$We study contributions to$pp\to W^+W^- \to \ell\nu_\ell \ell^\prime\nu_{\ell^\prime}$in models with a new Higgs boson,$H$, and a neutral lepton,$\nu_{4}$, with couplings$H-\nu_{4}-\nu_{\mu}$and$W-\nu_{4}-\mu$through the process$pp \to H \to \nu_4 \nu_\mu \to W \mu \nu_\mu \to \ell\nu_\ell \mu \nu_\mu$. Contrary to naive expectations, we find that contributions to$pp\to WW$can be very large while satisfying constraints from standard$H\to WW$and$H\to\gamma\gamma$searches. Even the excess observed by ATLAS in$pp\to WW$, if taken at face value, can be easily accommodated. The various kinematic distributions fit nicely the experimentally determined ones. This scenario can arise for example in a two Higgs doublet model with vectorlike leptons. Speaker: Seodong Shin (Indiana University) • 36 Higgs Trilinear Coupling as a Probe of Electroweak Phase Transition I am going to show that there is a tight correlation between the dynamics of the Electroweak Symmetry Breaking and the Higgs trilinear coupling. A large deviation of the Higgs trilinear coupling is expected for models exhibit a strong first order Electroweak Phase Transition. The Higgs trilinear coupling can be probed at the LHC by the double Higgs production process. Speaker: Peisi Huang (University of Chicago/Argonne) • 37 Improving Higgs coupling measurements through ZZ fusion at the ILC We evaluate the$e^-􀀀e^+\to e^-􀀀e^+h$process through the ZZ fusion channel at the International Linear Collider (ILC) operating at 500 GeV and 1 TeV center of mass energies. We perform realistic simulations on the signal process and background processes. With judicious kinematic cuts, we find that the inclusive cross section can be measured to$2.9\%$after combining the$500$GeV at$500~\text{fb}^{􀀀-1}$and$1$TeV at$1~\text{ab}^{-1}$runs. A multivariate log-likelihood analysis further improves the precision of the cross section measurement to$2.3\%$. We discuss the overall improvement to model-independent Higgs width and coupling determinations and demonstrate the use of different channels in distinguishing new physics effects in Higgs physics. Our study demonstrates the importance of the ZZ fusion channel to Higgs precision physics, which has often been neglected in the literature. Speaker: Zhuoni Qian (University of Pittsburgh) • QCD I G28 ### G28 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Prof. Zack Sullivan (Illinois Institute of Technology) • 38 Jet Energy Profiles for Electroweak Bosons At the LHC there will be highly boosted W, Z, and Higgs bosons. When these particles decay via the hadronic channel, they may form a single fat jet. We present a perturbative QCD factorization formula for substructures of an energetic Higgs jet, taking the jet energy profile resulting from the$H\to b\bar b$decay as an example. The formula is written as the convolution of a hard Higgs decay kernel with the jet functions of two$b$quarks and a soft function that links colors of the two$b$quarks. In a special factorization scheme with one thin$b$-quark jet and one fat$b$-quark jet, the soft function reduces to unity, and the analysis is greatly simplified. We demonstrate that the energy profile within a Higgs jet, which differs significantly from those of ordinary QCD jets, can improve the Higgs identification in the$H\to b\bar b$channel at the Large Hadron Collider. Our formalism is then extended to energy profiles of$W$- and$Z$-boson jets. Speaker: Joshua Isaacson (Michigan State University) • 39 W tagging using jet function We developed a concrete jet algorithm in 1411.3705 using the idea of identifying jets by maximizing certain jet functions. The idea can be generalized to more complex objects. I will show a simple extension of the jet function idea and its application in W-tagging. Speaker: Ran Lu • 40 Introducing P-jets: A priority based, noise tolerant jet algorithm With the increase in beam energy at the LHC comes a drastic increase in the number of minimum bias events occuring alongside the physics events. These pileup events will contaminate jet energy of reconstructed jets, in addition to producing many fake jets composed of purely pileup energy. Our proposed solution to this problem is to implement a new jet algorithm that combines the speed and theoretical stability of the k$_T$family of algorithms with the pileup exclusion that comes with jet pruning. This new jet algorithm, dubbed "p-jets," has shown promise in some simple simulations, and warrants further study. Speaker: Daniel Duffty (Illinois Institute of Technology) • 41 Flavor Tagging TeV Jets for BSM and QCD Track based techniques for tagging bottom-quark jets lose efficiency in the highly boosted regime. Many interesting channels require tagging of at least one b-jet ($W^{\prime}\rightarrow tb$,$Z^{\prime}\rightarrow t\bar{t}/b\bar{b}$, etc). We present a new method to tag b-jets with$p_{T}=\mathcal{O}\left(\mathrm{TeV}\right)$. Speaker: Keith Pedersen (Illinois Institute of Technology) • 42 Resonance Searches with an Updated Top Tagger The performance of top taggers, for example in resonance searches, can be significantly enhanced through an increased set of variables, with a special focus on final-state radiation. We study the production and the decay of a heavy gauge boson in the upcoming LHC run. For this purpose we use a new version of the HEPTopTagger which now includes an optimal choice of the size of the fat jet, N-subjettiness, and Qjets. For constant signal efficiency, the multivariate analysis achieves an increased background rejection by up to a factor 30 compared to our previous tagger. Speaker: Torben Schell (Heidelberg University) • 43 Jets at high multiplicity Facing ever higher energies at the LHC we are confronted with a huge amount of hadronic activity. However, the channels with many jets will also be among the most interesting ones. To either claim any discovery or proclaim yet another victory of the standard model we have to understand high multiplicity jet radiation precisely. Jet radiation in certain phase space regions shows particular patterns known as staircase respectively Poisson scaling. A common approach to high multiplicities are Parton Showers. However, from the random nature of Monte Carlo Markov Chains we are not able to understand, and thus trust and use, the occurrence of such patterns in our favor. Instead, we use the generating functional formalism of jet radiation as a tool to understand these patterns from a re-summation point of view. Although, this gives us a general handle to understand scaling patterns from first principles in QCD, it is not enough to understand the effects at a hadron collider. Therefore, we study additional sub-leading effects in the generating functional formalism as well as the effect of geometrical phase space effects in great details. This allows us to understand busy high multiplicity events much better. In addition, we also analyze the intermediate splitting scales as a first step in the study of more general scaling features in QCD. Speaker: Peter Schichtel (ITP) • SUSY I G31 ### G31 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Linda Carpenter (Ohio State University) • 44 Flavor symmetry based MSSM: Model building and phenomenology Flavor symmetries acting on the three chiral families can be consistently used to suppress SUSY flavor violation in gravity mediated SUSY breaking models. Models of this type will be presented, and the resulting MSSM phenomenology will be developed. Speaker: Kaladi Babu (Oklahoma State University) • 45 Radiative Breaking of the Minimal Supersymmetric Left-Right Model We propose a new variation to the SUSY Left-Right model (LRM) by extending the Minimal B-L model. Starting from energies of$\sqrt{s}>7$TeV, we can describe an intermediate scale for Grand Unification along the Pati-Salam path from SO(10). Here the breaking of$SU(2)_L\times SU(2)_R\times U(1)_{B-L}\rightarrow SU(2)_L\times U(1)_Y$is by a doublet rather than a triplet. Analyzing the RGE equations, the right handed neutral component of the doublet$L^c$acquires a negative mass squared at low energies. At least one generation spontaneously acquires a nonzero VEV and breaks the LRM symmetry into the MSSM. A seesaw is induced through gauge couplings maintaining light active neutrinos as well as heavy sterile neutrinos after Left-Right Breaking. Speaker: Mr Nathan Papapietro (University of Alabama) • 46 SUSY$\mu$term Generation via Radiative Breaking of PQ Symmetry The discovery of Higgs boson with mass$m_h=125.09\pm0.24$GeV confirms the particle content of the standard model but carries some fine-tuning questions along with it. While supersymmetry (SUSY) solves the Big Hierarchy problem (or EW fine tuning) involving quadratic divergences, there is a growing Little Hierarchy problem typified by the increasing gap between the W,Z and h masses ($\sim100$GeV) and the apparent mass scale of SUSY (multi-TeV range) by LHC sparticle mass bounds. It has been suggested that Little Hierarchy arises from a mismatch between Peccei-Quinn (PQ) and hidden sector intermediate scales$\nu_{PQ} \ll m_{hidden}$. An elegant model which exhibits this behavior was proposed by Murayama, Suzuki and Yanagida (MSY) where PQ symmetry is broken radiatively by driving one of the PQ scalars to negative mass-squared values. Starting with multi-TeV scalar masses and forbidding the$\mu$term in the superpotential, the radiatively-broken PQ symmetry naturally induces a SUSY$\mu$term$\sim100-200$GeV and generates Majorana right-handed neutrino masses. We conclude that Little Hierarchy is indeed a feature expected in SUSY axion models which address the gauge hierarchy problem, the strong CP problem and the SUSY$\mu$problem. In such scenario, we would expect dark matter to be comprised of an axion plus a higgsino-like admixture. Speaker: Hasan Serce (University of Oklahoma) • 47 R Parity Violation From Discrete R Symmetries With LHC not observing superpartners, minimal supersymmetric versions of the Standard Model (SM) are very constrained. We consider supersymmetric extensions of the SM in which the usual R or matter parity gets replaced by another R or non–R discrete symmetry that explains the observed longevity of the nucleon and solves the µ problem of MSSM. Such R-parity violating scenarios may lead to interesting phenomenology and explain why superpartners have not been observed yet. In order to identify suitable symmetries, we develop a novel method of deriving the maximal Abelian Z(R)N symmetry that satisfies a given set of constraints (such as those from anomaly freedom and phenomenology). We identify R parity violating (RPV) and conserving models that are consistent with precision gauge unification and also comment on their compatibility with a unified gauge symmetry such as the Pati–Salam group. We shall also provide a counter– example to the statement found in the recent literature that the lepton number violating RPV scenarios must have µ term and the bilinear κ L Hu operator of comparable magnitude. Finally, we will briefly comment on how baryogenesis and certain baryon number violating processes may arise within such simple models. Speaker: Volodymyr Takhistov (University of California at Irvine) • 48 Minimal Dirac gauginos without supersoftness I propose a mechanism for obtaining Dirac gaugino masses from an F-term VEV, without the usual accompanying "supersoft" scalar interactions. The mu problem can be solved in these models in a novel way, which decouples the Higgsinos from naturalness arguments. I will also briefly describe the resulting superpartner mass spectrum and make some comments on LHC phenomenology. Speaker: Prof. Stephen Martin (Northern Illinois University) • 49 Clues for Simplified Models from SUGRA Sparticle Hierarchies and LHC Data Sparticle mass hierarchies contain significant information regarding the origin and nature of supersymmetry breaking. The hierarchical patterns are severely constrained by electroweak symmetry breaking as well as by the astrophysical and particle physics data. They are further constrained by the Higgs boson mass measurement. The sparticle mass hierarchies can be used to generate simplified models consistent with the high scale models. The mass hierarchies and their truncated versions enlarge significantly the list of simplified models currently being used in the literature. It is seen that a knowledge of the spin-independent neutralino-proton cross section and the neutralino mass will narrow down the list of the allowed sparticle mass hierarchies. Thus dark matter experiments along with analyses for the LHC Run-II will provide strong clues to the nature of symmetry breaking at the unification scale. Speaker: Sujeet Akula (Northeastern University) • 50 LHC constraints on Mini-Split anomaly and gauge mediation and prospects for a future 100 TeV pp collider Stringent experimental constraints have raised the lower limit on the masses of squarks to TeV levels, while compatibility with the mass of the Higgs boson provides an upper limit. This two-sided bound has lead to the emergence of Mini-Split theories where gauginos are not far removed from the electroweak scale while scalars are somewhat heavier. This small hierarchy modifies the spectrum of standard anomaly and gauge mediation, leading to Mini-Split deflected anomaly and gauge mediation models. In this paper, we study LHC constraints on these models and their prospects at a 100 TeV collider. Current constraints on their parameter space come from ATLAS and CMS supersymmetry searches, the known mass of the Higgs boson, and the absence of a color-breaking vacuum. Prospects at a 100 TeV collider are obtained from these same theoretical constraints in conjunction with background estimates. As would be expected from renormalization group effects, a slightly lighter third generation of squarks is assumed. Higgsinos have masses similar to those of the scalars and are at the origin of the deflection. Speaker: Mr Hugues Beauchesne (Carleton University) • 51 The 2015+ Phenomenology of Deflected Mirage Mediation We consider the phenomenology of deflected mirage mediation, a "mixed" supersymmetry breaking scenario motivated by string compactifications in light of results from LHC8, PLANCK, and LUX. In this scenario, there are additional gauge mediation contributions along with the standard gravity and anomaly mediation contributions of the KKLT-motivated mirage mediation scenarios, which drastically alter the low energy spectrum. We place bounds on the parameter space and discuss the discovery prospects for novel spectra at LHC13, future dark matter direct detection experiments, and a future 100 TeV collider. Speaker: Todd Garon (UW-Madison) • 4:00 PM Coffee Break Benedum Hall G ### Benedum Hall G #### University of Pittsburgh Pittsburgh, PA 15260 • BSM II G27 ### G27 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Dr Hooman Davoudiasl (BNL) • 52 Mini-Review: New Resonances - Theory and Searches Speaker: Prof. R. Sekhar Chivukula (Michigan State University) • 53 Separating Dijet Resonances using the Coloron Discriminant Variable at LHC An exciting possibility for the upcoming 14 TeV run of the LHC is that a new strongly-coupled resonance decaying to dijets could be discovered. Once the resonance is detected, the immediate questions will be about the nature of the particle: is it colored? is it a vector, fermion, or scalar? This talk reviews the LHC discovery reach for a variety of dijet resonances and discusses a strategy for measuring the newly discovered state's properties. The method relies on the color discriminant variable, which can be readily be determined at the LHC from the measurements of the di-jet signal cross section, the resonance mass and the resonance width. We discuss the ability of this method to distinguish between a qg excited quark resonance, a qqbar coloron, a qqbar Z', and a gg color-octet scalar. Speaker: Prof. Elizabeth Simmons (Michigan State University) • 54 Distinguishing dijet resonances at the LHC using jet energy profiles Anticipating that a dijet resonance could be discovered at the 14 TeV LHC, we present a method to discern whether it is a quark-antiquark ($q\bar{q}$), quark-gluon ($qg$), or gluon-gluon ($gg$) resonance, which is based on the study of the energy profiles of the two leading jets in the dijet channel. Including statistical uncertainties in the signal and the QCD backgrounds, we show that one can distinguish, in a model-independent way, between$q\bar{q}$,$qg$, and$gg$resonances; an evaluation of systematic uncertainties in the measurement of the jet energy profile will require a detailed detector study once sufficient 14 TeV dijet data are in hand. Speaker: Natascia Vignaroli (Michigan State University) • 55 Color Discriminant Variable to Seperate Coloron and Leptophobic Z' at the LHC A vector resonance decaying to dijets could be discovered at the 14 TeV run of the LHC. Measurements available after the discovery of the resonance; namely, the dijet cross section, mass and width of the resonance, can determine its color structure via a method using the color discriminant variable. This talk illustrates that the measurements of the resonance's heavy flavor decays to top and bottom quark pairs help distinguish coloron and leptophobic Z' with flavor non-universal couplings to quarks. The method works for a large region of parameter space despite the fact that couplings to light quarks are generally inaccessible to experiments, and that the Z' could have non-Standard invisible decays. Speaker: Pawin Ittisamai (Michigan State University) • 56 Searches for new physics in high-mass di-fermion final states with the ATLAS detector at the LHC Many new physics scenarios beyond the Standard Model predict resonant or non-resonant production of a pair of high-transverse momentum fermions (light and heavy quarks, charged leptons and neutrinos). The high-mass resonant production of top-quark pairs or a top-quark and a bottom-quark is also a good benchmark process for boosted top-quark and high-pT b-quark tagging. This talk summarizes searches in di-fermion final states at the ATLAS experiment in LHC Run 1. Speaker: Jason Robert Veatch (University of Arizona (US)) • 57 Search for ttbar resonances at CMS A search is presented for resonant top quark pair production. The full dataset recorded with the CMS detector in proton-proton collisions at a centre-of-mass energy of 8 TeV is used. The search is performed by measuring the invariant mass distribution of the top-quark pair and testing for deviations from the Standard Model prediction. Final states with no, one or two leptons are considered and the selection is optimized accordingly, taking into account the high Lorentz boost of the top quarks at high invariant masses. The results are presented from a combination of all channels. Speaker: Irving Daniel Sandoval Gonzalez (University of Illinois at Chicago (US)) • 58 Heavy Colour-Octet Particles at the LHC The top quark may hold the key to new physics associated with the electroweak symmetry-breaking sector. Many models beyond the Standard Model, especially those with a colour-triplet top-quark partner, contain a heavy colour-octet state. The "naturalness" argument for a light Higgs boson suggests that the colour octet can be pair-produced with large cross sections at the Large Hadron Collider (LHC). It may decay preferentially via a top partner to a color-singlet state -- a candidate for cold dark matter. The resulting experimental signatures of such new physics may be distinctive, yet challenging to disentangle. We systematically categorize the new particles according to their spin and gauge quantum numbers. Optimizing the search strategy, we study the LHC's expected discovery reach. Furthermore, we explore the determination of the new particles' properties, such as spin, couplings, and whether the fermionic octet is a Majorana particle. Speaker: Keith Lee • Cosmology II G26 ### G26 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Brian Thomas Batell (CERN) • 59 Possible Evidence for Resonant Particle Production during Inflation from the CMB Power Spectrum The power spectrum of the cosmic microwave background from both the Planck and WMAP data exhibits a slight dip in the vicinity of$l= 20-30$. We show that such a dip could be the result of resonant creation of a massive particle that couples to the inflaton field. For our best-fit models, epochs of resonant particle creation reenter the horizon at wave numbers of$k_* \sim 0.00011 \pm 0.0004 $($h$Mpc$^{-1}$). The amplitude and location of these features correspond to the creation of fermion species of mass$\sim 1-2$M$_{pl}$during inflation with a coupling constant between the inflaton field and the created fermion species of near unity. Although the evidence is marginal, if this interpretation is correct, this could be one of the first observational hints of new physics at the Planck scale. Speaker: Mr Mayukh Gangopadhyay (Graduate Student) • 60 Primordial non-gaussianity from the bispectrum of 21cm fluctuations in the dark ages Measuring primordial non gaussianity will be the next observational milestone for inflation studies, since it will help us set apart the different inflationary models. CMB observations of non gaussianity are cosmic-variance limited and, at this point, almost all the information possible has been extracted. A popular alternative is the 21-cm line during the dark ages ($z \sim 30 - 100$). The absence of a damping (Silk) scale during this epoch enables us to reach scales much smaller than with CMB studies, which added to using information from different redshift slices can greatly improve upon current bounds. We study the theoretical prospects for these observations. As opposed to CMB anisotropies, which are highly linear, the 21-cm fluctuations are intrisincally non linear, generating secondary non gaussianities. The main secondary contributions come from gravitational evolution and the non-linear dependence of the tracer on the underlying density field. These secondary non gaussianities can be highly correlated with the primordial one, so a careful Fisher analysis is needed. We find that the correlations lower the signal-to-noise ratio by a factor of$\sim 10$from naive (uncorrelated) studies, such as the ones in the literature. An experiment with a bandwith of 1 MHz and angular resolution of 1/10 of arcminute could achieve a detection on the order of$f_{\mathrm NL}^{\mathrm{local}} \sim 0.07$,$f_{\mathrm NL}^{\mathrm{equil}} \sim 3.3$and$f_{\mathrm NL}^{\mathrm{ortho}} \sim 1.5$in the cosmic-variance limit. Speaker: Julian Munoz Bermejo (Johns Hopkins University) • 61 Higgs Inflation, Seesaw Physics and Fermion Dark Matter We present an inflationary model in which the Standard Model Higgs doublet field with non-minimal coupling to gravity drives inflation, and the effective Higgs potential is stabilized by new physics which includes a dark matter particle and right-handed neutrinos for the seesaw mechanism. All of the new particles are fermions, so that the Higgs doublet is the unique inflaton candidate. With central values for the masses of the top quark and the Higgs boson, the renormalization group improved Higgs potential is employed to yield the scalar spectral index$n_s \simeq 0.968$, the tensor-to-scalar ratio$r \simeq 0.003$, and the running of the spectral index$\alpha=dn_s/d \ln k \simeq -5.2 \times 10^{-4}$for the number of e-folds$N_0=60$($n_s \simeq 0.962$,$r \simeq 0.004$, and$\alpha \simeq -7.5 \times 10^{-4}$for$N_0=50$). The fairly low value of$r \simeq 0.003$predicted in this class of models means that the ongoing space and land based experiments are not expected to observe gravity waves generated during inflation. Speaker: Prof. Nobuchika Okada (University of Alabama) • 62 Light Inflaton - hunting for it from CMB through the Dark Matter and down to the colliders The models without additional energy scales (heavy particles) above the electroweak scale can provide relation between the low energy physics and cosmology. Probably the simplest example is the model with additional singlet scalar inflaton (with non-minimal coupling). It gets constraint simultaneously from the inflationary observations (tensor modes), dark matter production (for 7keV sterile neutrino DM), and searches in the rare decays. I will discuss the interplay of the cosmological and laboratory constraints in this model. Speaker: Fedor Bezrukov (CERN & University of Connecticut (US) & RIKEN BNL (US)) • 63 Affleck-Dine Sneutrino Inflation Motivated by the coincidence between the Hubble scale during inflation and the typical see-saw neutrino mass scale, we present a supergravity model where the inflaton is identified with a linear combination of right-handed sneutrino fields. The model accommodates an inflaton potential that is flatter than quadratic chaotic inflation, resulting in a measurable but not yet ruled out tensor-to-scalar ratio. Small CP-violation in the neutrino mass matrix and supersymmetry breaking yield an evolution in the complex plane for the sneutrino fields. This induces a net lepton charge that, via the Affleck-Dine mechanism, can be the origin of the observed baryon asymmetry of the universe. Speaker: Jason Evans (University of Minnesota) • 64 Holographic models with a small cosmological constant at Finite Temperature The cosmological constant problem can be reformulated in the brane world models. In this talk I will discuss a “soft-wall” realization of the Randall Sundrum geometry where the infrared brane plays a lesser role as a cutoff for large curvature effects and low energy observables such as spectrum of states are largely insensitive to its position. I will explore the finite temperature behavior of such models by studying geometries which include a horizon or a “black brane” along the extra dimension in the presence of non-trivial scalar field vacuum expectation value. A first order geometric phase transition proceeds via bubble nucleation between the two different gravity solutions. I shall then compare these results to the Randall Sundrum phase transition with Goldberger-Wise stabilization. Speaker: Bithika Jain (Syracuse University) • 65 Running Non-Minimal B-L Inflation with Stabilized Inflaton Potential We consider$\lambda \phi^4$inflation with non-minimal gravitational coupling in the context of the minimal B-L extension of the Standard Model, where the B-L Higgs field with a$+2$B-L charge is identified as an inflaton. When quantum corrections for the inflation potential are taken into account, the instability of the potential occurs because of the small quartic coupling during the inflation.Imposing a condition on the beta function of the quartic coupling to remove the instability, we analyze the slow-roll inflation scenario to obtain the inflationary predictions as well as predictions for low energy observables such as the mass ratio of the B-L gauge boson to the right handed neutrinos and the inflaton mass. With the correlations between the inflationary predictions and the low energy observables, more precise measurements of the inflationary predictions in the future experiments can give a more severe constraint on low energy observables. On the other hand, search for the minimal B-L model can also provide constraint on the inflationary predictions. Speaker: Mr Digesh Raut (Department of Physics, University of Alabama) • 66 Reheating Predictions in Single Field Inflation One possibility for studying reheating is to link the duration and final temperature after reheating, as well as its equation of state, to inflationary observables. For single-field inflationary models, if we approximate reheating by a constant equation of state, one can derive relations between reheating parameters and the scalar power spectrum amplitude and spectral index. While this is a simple approximation, by restricting the equation of state to lie within a broad physically allowed range, one can in turn bracket an allowed range of$n_s$and$r$for these models. The added constraints can help break degeneracies between inflation models that otherwise overlap in their predictions. Speaker: Jessica Cook (Arizona State) • Dark Matter II G29 ### G29 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Joel Wesley Walker (Texas A & M University (US)) • 67 Dark Matter Searches with a Mono-Z' Jet We study collider signatures of a class of dark matter models with a GeV-scale dark Z'. At hadron colliders, the production of dark matter particles naturally leads to associated production of the Z', which can appear as a narrow jet after it decays hadronically. Contrary to the usual mono-jet signal from initial state radiation, the final state radiation of dark matter can generate the signature of a mono-Z' jet plus missing transverse energy. Performing a jet-substructure analysis to tag the Z' jet, we show that these Z' jets can be distinguished from QCD jets at high significance. Compared to mono-jets, a dedicated search for mono-Z' jet events can lead to over an order of magnitude stronger bounds on the interpreted dark matter-nucleon scattering cross sections. Speaker: James Bourbeau (University of Wisconsin) • 68 Muon$(g-2)_{\mu}$, Neutralino Dark Matter and the LHC We study the muon$(g-2)_{\mu}$anomaly in light of neutralino dark matter and the LHC. We scan the MSSM parameters relevant to$(g-2)_{\mu}$and focus on three different cases with different neutralino compositions. For$\tan\beta=10$, we find that the 2$\sigma$range of$(g-2)_{\mu}$requires the smuon ($\tilde{\mu}_1$) to be lighter than$\sim$500 GeV. The neutralinos,$\tilde{\chi}^{0}_{1},\tilde{\chi}^{0}_{2}$, have to be lighter than$\sim$300 GeV and$900$GeV respectively. In contrast, for$\tan\beta=50$, the corresponding upper limits are$\sim 1$TeV for$\tilde{\mu}_1$and$\sim 650$GeV for$\tilde{\chi}^{0}_{1}$and 1 TeV for$\tilde{\chi}^{0}_{2}. We thereby study the prospects of searching these light smuons and neutralinos at the LHC, in conjunction with constraints coming from indirect detection experiments of dark matter. Speaker: Mr Tathagata Ghosh (Texas A&M University) • 69 Axinos at the LHC SUSY models with a modified dark sector require constraints to be reinterpreted, which may allow for scenarios with low tuning. A modified dark sector can also change the phenomenology greatly. The addition of the QCD axion to the MSSM solves the strong CP problem and also modifies the dark sector with new dark matter candidates. This talk describes scenarios where the axion's superpartner, the axino may be detectable at the LHC in the decays of neutralinos displaced from the primary vertex. The prospects of distinguishing this scenario from similar decays of neutralinos with gravitinos or RPV are discussed. Speaker: Christopher Redino (SUNY at Buffalo) • 70 Semi-visible Jets: Dark Matter Undercover at the LHC The dark matter may be a remnant of strong dynamics that is accessible via a weakly coupled portal. If the hidden-sector states are produced at the Large Hadron Collider (LHC), they would undergo a QCD-like shower yielding a spray of stable invisible dark matter along with unstable states that decay back to the Standard Model. Such “semi-visible” jets arise, for example, when their production and decay are driven by a leptophobic Z resonance; the resulting signature is characterized by significant missing energy aligned along the direction of one of the jets. These events are vetoed by the current suite of searches employed by the LHC, resulting in low acceptance. This Letter will demonstrate that the transverse mass—computed using the final-state jets and the missing energy—provides a powerful discriminator between the signal and the QCD background. Assuming that the Z couples to the Standard Model quarks with the same strength as the Z 0 , the proposed search can exclude Z masses below 3.6 TeV with 100 fb^-1 of 14 TeV data at the LHC. Speaker: Hou Keong Lou (Princeton University) • 71 Cuts, Correlations, and Collider Searches for Non-Minimal Dark Sectors Distinguishing between traditional dark-matter models and models with non-minimal dark sectors at hadron colliders is an endeavor which typically requires a detailed analysis of the distributions of relevant kinematic variables rather than simply an identification of an excess in event count. Distribution-based searches of this sort are particularly subtle because cuts imposed on one collider variable for the purposes of background reduction can distort the kinematic distributions of other collider variables with which the first variable is non-trivially correlated. Such distortions can obscure --- or in certain cases, actually enhance --- the distinctiveness of the resulting distributions. In this talk, discuss the prospects for distinguishing between traditional dark-matter models and models with non-minimal dark sectors at the LHC on the basis of events with two hadronic jets and substantial missing energy. I examine how cuts on one or more of the relevant collider variables in this channel affect the distributions of others and discuss strategies for optimizing our ability to distinguish between different models of the dark sector at the upgraded LHC. Speaker: Prof. Brooks Thomas (Reed College) • 72 Constraining models with an additional large electroweak scalar multiplet Models with a single additional large electroweak scalar multiplet provide a simple extension to the Standard Model. Such models may also provide a natural dark matter candidate. It is then of great interest to determine what constraints, if any, are to be placed on these models. In this talk, we examine two different classes of models: those with an accidentalU(1)$symmetry, and those with an imposed$Z_{2}$symmetry. We use a combination of tree-level perturbative unitarity, electroweak precision measurements, cosmological relic density, direct detection limits, and LHC studies to constrain these models. Speaker: Terry Pilkington (Carleton University) • 73 Boosted Dark Matter enhanced with self-interactions We explore detection prospects of a non-standard dark sector in the context of boosted dark matter, which could be detected as visible Cherenkov light in large volume neutrino detectors. In models with multiple candidates, self-interaction of dark matter particles is naturally utilized in the assisted freeze-out mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation. We show that self-interaction of the secluded (heavier) dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We perform a detailed analysis of the boosted dark matter events for Super-K, Hyper-K and PINGU. Speaker: Gopolang Mohlabeng (University of Kansas) • Higgs II G30 ### G30 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Adam Orion Martin (University of Notre Dame (US)) • 74 The Higgs Cross Section at N3LO I will present the Higgs production cross section in gluon fusion at N3LO in QCD. I will discuss the calculation and its impact for Higgs phenomenology. Speaker: Falko Dulat (ETH Zurich) • 75 The role of low-energy observables in precision Higgs analysis A conventional approach to precision calculations of Higgs boson observables uses quark masses$m_c$and$m_b$as inputs. However, quark masses are single numbers that hide a variety of low-energy data from which they are extracted, and also hide the various sources of theoretical uncertainties and correlations with additional input parameters such as$\alpha_s$. Higher-precision calculations, which are needed to give meaning to future measurements, require more direct engagement with the low-energy data in a global analysis. We present an initial calculation in this direction, which illustrates the procedure and reveals some of the theory uncertainties that challenge subpercent determinations of Higgs boson partial widths. Speaker: Zhengkang Zhang (University of Michigan) • 76 Search Strategies for Composite Higgs Models at LHC run II Composite Higgs Models provide an attractive extension of the Standard Model which solves the hierarchy problem and predicts new resonances at the TeV scale which can be observed at the LHC run II. In most composite models, the new resonances include colored top/light quarks partner states. In this talk, we present results on several new search strategies for such heavy vector-like quark partners at the early stages of the LHC run-II. In particular, we show that identifying tops, Z and W bosons, and higgses with very high momenta are the key to heavy quark partner searches and how jet-substructure techniques can maximize the sensitivity to such signatures. Speaker: Jeong Han Kim (KAIST) • 77 The Unnatural Composite Higgs Composite Higgs models can trivially satisfy precision-electroweak and flavour constraints by simply having a large spontaneous symmetry breaking scale, f > 10 TeV. This produces a 'split' spectrum, where the strong sector resonances have masses greater than 10 TeV and are separated from the pseudo Nambu-Goldstone bosons, which remain near the electroweak scale. Even though a tuning of order$10^{-4}$is required to obtain the observed Higgs boson mass, the big hierarchy problem remains mostly solved. Intriguingly, models with a fully-composite right-handed top quark also exhibit improved gauge coupling unification. By restricting ourselves to models which preserve these features we find that the symmetry breaking scale cannot be arbitrarily raised, leading to an upper bound f < 100-1000 TeV. This implies that the resonances may be accessible at future colliders, or indirectly via rare-decay experiments. Dark matter is identified with a pseudo Nambu-Goldstone boson, and we show that the smallest coset space containing a stable, scalar singlet and an unbroken SU(5) symmetry is SU(7) / SU(6) x U(1). The colour-triplet pseudo Nambu-Goldstone boson also contained in this coset space is metastable due to a residual symmetry. It can decay via a displaced vertex when produced at colliders, leading to a distinctive signal of unnaturalness. Speaker: Andrew Spray (CoEPP, University of Melbourne) • 78 Exotic Higgs Decays at LHC and Beyond Models of Electroweak Symmetry Breaking, with an extended Higgs sector, are theoretically well motivated. In addition to to SM-like Higgs boson, in these models the low energy spectrum includes other CP-even Higgses$H$, CP-odd Higgses$A$, as well as charged ones$H^\pm$. Conventional search strategies focus on Higgs decays into a pair of SM fermions or gauge bosons. However, exotic decay channels in which a heavy Higgs decays into two lighter Higgses or a light Higgs plus vector boson final state can open up and might even dominate. While the appearance of exotic decays reduce the reach of the conventional search strategies, it also offers new discovery channels for non-SM like Higgses. In this talk, we present an overview of exotic Higgs decays and discuss their reach at LHC and a future 100 TeV collider. Speaker: Felix Kling (University of Arizona) • 79 Search for non Standard Model Higgs boson decays in events with boosted dimuons Several models of new physics predict the existence of new light bosons that are weakly coupled to SM particles. Two examples include SUSY with a "dark" sector (in which the new light bosons can also be relatively long-lived) or models with an extended Higgs sector, e.g. NMSSM. In these scenarios, the new bosons can be produced either in the Higgs decays or as part of SUSY cascades. Non-SM decays of the Higgs can either hide the Higgs boson from standard searches or slightly alter the measured cross-section of the SM Higgs boson candidate observed at the LHC. Direct searches for non-SM decays of the Higgs boson provide a complementary approach to SM Higgs searches and can help further understand the nature of Higgs boson by either confirming or rejecting large classes of BSM scenarios. We present the status and recent results of a search for a non-SM Higgs boson decaying to a pair of new light bosons, each of which consequently decays into boosted dimuon final state using the LHC data collected by the CMS experiment. Speaker: Sven Dildick (Texas A & M University (US)) • 80 Uncovering light scalars with exotic Higgs decays to bbmumu The search for exotic Higgs decays are an essential probe of new physics. The small width of the Higgs boson makes its decay uniquely sensitive to the existence of light hidden sectors. We assess the potential of an exotic Higgs decay search for h -> 2X -> bbmumu to constrain theories with light CP-even and CP-odd singlet scalars. This decay arises naturally in many scenarios, such as the Standard Model augmented with a singlet, the two-Higgs-doublet model with a singlet (2HDM+S) -- which includes the Next-to-Minimal Supersymmetric Standard Model (NMSSM) -- and in hidden valley models. The 2b2mu channel may represent the best discovery avenue for many models. It has competitive reach, and is less reliant on low-pT b- and tau-reconstruction compared to other channels like 4b, 4tau, and 2tau2mu. We analyze the sensitivity of a 2b2mu search for the 8 and 14 TeV LHC, including the HL-LHC and find that Br(h -> 2X -> 2b2mu) can be constrained at the few x 10^-5 level at the HL-LHC. Speaker: Yiming Zhong (Stony Brook University) • 81 Light Charged Higgs Bosons in Single-Top Production The Two Higgs Doublet Model (2HDM) is one of the simplest extensions to the Standard Model Higgs sector, and predicts the existence of additional Higgs bosons, including a pair of charged Higgs bosons$H^\pm$and a pseudoscalar Higgs boson$A$. Existing searches for the charged Higgs mostly focus on the$H^\pm\rightarrow\tau\nu /cs$decay channels. For light$A$’s,$H^\pm\rightarrow AW$becomes kinematically accessible and competitive with the conventional channels. We examine the single top production channel with$t\rightarrow bH^\pm$, and the subsequent decay chain of$H^\pm\rightarrow AW\rightarrow\tau\tau l\nu$. We perform a collider analysis and obtain exclusion and discovery reach at the 14 TeV LHC with 100 fb−1 integrated luminosity. We further study the implication of the search limits on the Type II 2HDM. Speaker: Adarsh Pyarelal (urn:Facebook) • QCD II G28 ### G28 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Fatima Machado • 82 PDFs for Run 2 at the LHC New generations of PDFs have recently been developed by the major global PDF fitting groups. In addition, new techniques have also been developed towards more efficient calculations of PDF uncertainties using the error PDFs from those groups. I will discuss developments in both areas and their implications for Run 2 physics. Speaker: Prof. Joey Huston (Michigan State University (US)) • 83 Recent results on jets, alpha_s extraction and PDFs from CMS Recent jets results from CMS at a centre of mass energy of 7 and 8 TeV are presented. The comparison with predictions from perturbative QCD at next-to-leading order allow the inference of important theory parameters from these measurements. Particular emphasis is put on the determination of parton distribution functions of the proton and the confirmation of the running and value of the strong coupling constant alpha_S. Speaker: Fred Stober (KIT - Karlsruhe Institute of Technology (DE)) • 84 Recent QCD results from ATLAS The ATLAS collaboration has performed studies of a wide range of QCD phenomena, from soft particle to hard photon and jet production. Recent soft-QCD measurements include studies of the underlying event properties, polarisation of Lambda particles and Bose-Einstein correlations. The measurement of diffractive di-jet production with a large rapidity gap devoid of hadronic activity tests the interplay of soft and hard phenomena. Differential measurements of inclusive, di-jet, tri-jet and multi-jet production provide stringent tests of high-order QCD predictions and provide input for determination of parton density functions and the strong coupling constant. Precision measurements of the isolated high pT inclusive photon cross section test the theoretical predictions and constrain parton density functions. An overview of these results is given. Speaker: Javier Llorente Merino (Universidad Autonoma de Madrid (ES)) • 85 D± production asymmetry at the LHC from heavy quark recombination mechanism The asymmetry in the forward region production cross section of D± is calculated using the heavy quark recombination mechanism for pp collisions at 7 TeV. By suitable choices of four nonperturbative parameters, our calculated results can reproduce those obtained at LHCb. We find A p ∼ −1% when integrated over 2.0 GeV < p T < 18 GeV and 2.2 < η < 4.75, which agrees with A p = −0.96 ± 0.26 ± 0.18% as measured by LHCb. Furthermore, the calculated distributions in η and p T agree reasonably well with those obtained at LHCb. Predictions on production asymmetry of heavy baryons are also made in the same formalism. Speaker: Lai Wai Kin (University of Pittsburgh) • 86 Quarkonia production with the ATLAS experiment ATLAS has a wide program to study the production cross section and decay properties of the charmonium and bottomonium states. This presentation will cover ATLAS results in the domain of charmonium production, including J/psi, psi(2s) and chi_c states, as well as exotic state X(3872) and search for its bottomonium couterpart X_b in several possible decay channels. We also review the studies of di-J/psi and associated vector boson + J/psi production. These rare production modes provide novel insight into the mechanisms of charmonium production and the impact of proton structure on these observables. Speaker: Benjamin Weinert • 87 Diquark bound states at far beyond ladder truncation The Bethe-Salpeter equation in the diquark channel is investigated by employing the Dyson-Schwinger method together with the Munczek-Nemirovsky model. The novelty of our study is a resummation of completely-crossed ladder diagrams in the Bethe-Salpeter kernel. These diagrams are enhanced due to their color factors in the diquark channel, but not in the meson channel. As a result of our analysis, it is suggested that diquark bound-state solutions exist in the Bethe-Salpeter equation, which have been thought to be absent. Speaker: Go Mishima (Japan/U-Tokyo) • 88 An independent data analysis of the proton size puzzle Recent experiments indicate the proton radius in muonic hydrogen is about 4% smaller than the proton radius in ‘ordinary’ hydrogen. Previous analysis puts the size of the discrepancy at 7 sigma if the 'ordinary' radius is calculated from a combination of spectroscopy and electron-proton scattering data. Same analysis however is found to be excessively sensitive to a single transition whose theoretical uncertainty is hundreds to thousands of times larger than its experimental uncertainty. We delete this transition as an "outlier" and perform an independent analysis using a simple, transparent procedure where the relation between procedural decisions, data, and theory inputs on final outputs can be readily monitored. Such an approach revises the discrepancy to 2.5-3.5 sigma. Speaker: John Martens (University of Kansas) • SUSY II G31 ### G31 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Matthew Baumgart (Carnegie Mellon University) • 89 125 GeV Higgs from Tree-level A-terms We present a new mechanism to generate large A-terms at tree-level in the MSSM through the use of superpotential operators. The mechanism trivially resolves the A/m^2 problem which plagues models with conventional, loop-induced A-terms. We study both MFV and non-MFV models; in the former, naturalness motivates us to construct a UV completion using Seiberg duality. Finally, we study the phenomenology of these models when they are coupled to minimal gauge mediation. We find that after imposing the Higgs mass constraint, they are largely out of reach of LHC Run I, but they will be probed at Run II. Their fine tuning is basically the minimum possible in the MSSM. Speaker: Aria Basirnia (Rutgers University) • 90 Dirac Triplet Extension of the MSSM We explore extensions of the Minimal Supersymmetric Standard Model involving two SU(2)L triplet superfields that share a superpotential Dirac mass yet only one of which couples to the Higgs fields. This choice is motivated by recent work using two singlet superfields with the same superpotential requirements. We find that, as in the singlet case, the Higgs mass in the triplet extension can be raised to 125 GeV without introducing large fine-tuning. For triplets that carry hypercharge, the regions of least fine tuning are characterized by small contributions to the T parameter, and light stop squarks, m(stop) ∼ 300 − 450 GeV; the latter is a result of the tan(beta) dependence of the triplet contribution to the Higgs mass. Despite such light stop masses, these models are viable provided the stop-electroweakino spectrum is sufficiently compressed. Speaker: Carlos Alvarado (University of Notre Dame) • 91 Implications of naturalness for the heavy Higgs bosons of supersymmetry Recently, it has been argued that various measures of SUSY naturalness- electroweak, Higgs mass and EENZ/BG- when applied consistently concur with one another and make very specic predictions for natural supersymmetric spectra. Highly natural spectra are characterized by light higgsinos with mass not too far from m_h and well-mixed, but TeV- scale, third generation squarks. We apply the unied naturalness measure to the case of heavy Higgs bosons A, H, and H^\pm. We find that their masses are bounded from above by naturalness depending on tan\beta: e.g. for 10% fine-tuning and tan\beta ~ 10, we expect m_A \le 2.5 TeV whilst for 3% fine-tuning and tan\beta as high as 50, m_A \le 8 TeV. Furthermore, the presence of light higgsinos seriously alters the heavy Higgs boson branching ratios, thus diminishing prospects for usual searches into Standard Model (SM) natural states, while new discovery possibilities arise due to the supersymmetric decay modes. The heavy SUSY decay modes tend to be H; A; H^\pm \Rightarrow W; Z; or h+ missing E_T + soft tracks so that single heavy Higgs production is characterized by the presence of high p_T W, Z, or h bosons plus missing E_T. These new heavy Higgs boson signatures seem to be challenging to extract from SM backgrounds. Speaker: Michael Savoy • 92 Is the higgs the first supersymmetric particle? The LHC collaborations are putting forth tremendous efforts to find supersymmetry at the TeV scale. However, they are yet to find any conclusive hints of physics beyond the Standard Model. Meanwhile, both ATLAS and CMS have discovered a new scalar at 125 GeV which appears compatible with the Standard Model Higgs. Recently, the possibility that the Higg's doublet is the superpartner of one of leptons has been seriously considered and its been found that such models are well within current bounds. In this talk I explore novel phenomenological implications of this intriguing possibility as well as categorize the different types of allowed models in this framework. Speaker: Jeff Dror (Cornell University) • 93 Searches for squarks and gluinos with the ATLAS detector Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results on searches for supersymmetric squarks and gluinos, including third generation squarks produced directly or via decay of gluinos, using 20/fb of sqrt(s)=8 TeV p-p collision data. The searches involved final states containing jets (possibly identified as coming from b-quarks), missing transverse momentum with and without light leptons, taus or photons. Prospects for some of the early SUSY searches with sqrt(s) = 13 TeV data will also be presented. Speaker: Yousuke Kataoka (University of Tokyo (JP)) • 94 Probing Light Stops with Stoponium We derive new limits on light stops using resonance searches in the channels of diphoton, Z+photon, WW, ZZ and hh. Remarkably, we find that stoponium searches are highly complementary to direct collider searches as well as indirect probes such as Higgs coupling measurements and electroweak precision test. The diphoton is most complementary as it is maximally sensitive when the Higgs-stop-stop coupling vanishes and no direct and indirect constraints exist. Interestingly, we also find that the Z+photon can give a stronger constraint if the stop is primarily left-handed. We finally discuss relevant parameter space in several SUSY models in which stoponium signatures arise. Our results are based on quarkonium-inspired potential model and first two S-wave states. Speaker: Sunghoon Jung • 95 Searches for electroweak production of supersymmetry, supersymmetry in resonance production, R-parity violating signatures and events with long-lived particles with the ATLAS detector This talk presents the latest ATLAS results in the context of electroweak production of SUSY particle, R-Parity violating SUSY scenarios, and scenarios with long-lived SUSY particles. The results presented use the full 20/fb of sqrt(s)=8TeV p-p collisions collected by the ATLAS experiment in 2012. The prompt searches consider final states including leptons, jets (including b-jets) and missing energy, whereas the dedicated searches for long lived SUSY particles utilize abnormal specific energy loss, appearing or disappearing tracks, displaced vertices, long time-of-flight or late calorimetric energy deposits. Speaker: Preema Rennee Pais (University of Massachusetts (US)) • 96 Explored and Unexplored MSSM Signatures The R-parity conserving minimal supersymmetric Standard Model (MSSM) is a possible description of nature that is motivated by its providing a natural explanation for the hierarchy problem and a possible account of cosmic dark matter. The vastness of the full model space of the MSSM, which spans over 100 dimensions, has motivated the interpretation of CMS results in terms of a proxy model for the MSSM called the phenomenological (p)MSSM. The pMSSM captures most of the LHC-relevant features of the MSSM while reducing the number of parameters down to a tractable 19. I will present results from this analysis, including how CMS has impacted our understanding of the pMSSM, and touch on signatures that are predicted to become accessible in the upcoming 13 TeV run. Speaker: Samuel Louis Bein (Florida State University (US)) • Tuesday, May 5 • 8:00 AM Breakfast Alumni Hall 7th Floor ### Alumni Hall 7th Floor #### University of Pittsburgh Pittsburgh, PA 15260 • Plenary III Alumni Hall 7th Floor Auditorium ### Alumni Hall 7th Floor Auditorium #### University of Pittsburgh Pittsburgh, PA 15260 Convener: K. Babu • 97 B-Physics: The Next Generation Speaker: Prof. Tom Browder (University of Hawaii) • 98 Flavor Physics in the New Era Speaker: Wolfgang Altmannshofer (Perimeter Institute) • 99 Pushing the Frontiers of Perturbative QCD Speaker: Jesse Kempner Thaler • 10:30 AM Symposium Photo & Coffee Break Alumni Hall 7th Floor ### Alumni Hall 7th Floor • Plenary IV Alumni Hall 7th Floor Auditorium ### Alumni Hall 7th Floor Auditorium #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Tom Rizzo • 100 EFT: Theory and Practice Speaker: Aneesh Manohar • 101 Dark Matter Direct Detection Speaker: xiangdong ji (u) • 102 Dark Matter: Theory and Searches Speaker: Tracy Slatyer (Harvard University) • 12:45 PM Lunch Oakland Area ### Oakland Area #### University of Pittsburgh Pittsburgh, PA 15260 • BSM III G31 ### G31 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: James Gainer (University of Florida (US)) • 103 Search for new physics in the low MET monophoton channel with the CMS Detector With the recent discovery of the Higgs boson at the Large Hadron Collider, the goals of the Compact Muon Solenoid (CMS) Experiment are now focused on probing for new physics beyond the standard model. The final state consisting of a low transverse energy photon and low missing transverse energy (MET), also called the “monophoton” final state, can be used to constrain a variety of extensions of the standard model, including supersymmetry. I present a search for new physics in this low MET monophoton channel using 7.3/fb of 8 TeV LHC collected with the CMS detector, as part of our parked data program. This analysis extends the high-energy single-photon searches to a lower-energy regime. In the absence of deviations from the standard model predictions, limits are set on the production cross section of exotic decays of the Higgs boson. In addition, we present model independent limits as a function of MET requirement. Speaker: Toyoko Orimoto (Northeastern University (US)) • 104 Characterizing Invisible Electroweak Particles through Single-Photon Processes in$e^+e^-$Colliders In light of the stringent bounds on the BSM new states from the CERN Large Hadron Collider (LHC) searches, we explore the situation where the only accessible new states at the electroweak scale consist of a pair of non-colored and electroweak particles, which are degenerate at the tree level and split only by electroweak symmetry breaking at the loop level. To be specific, we consider an underlying supersymmetric model and focus on the cases with only (a) two spin-1/2 higgsino$SU(2)_L$doublets, (b) a spin-1/2 wino$SU(2)_L$triplet and (c) a spin-0 left-handed slepton$SU(2)_L$doublet. In this situation, even the electrically charged particle of each pair is not easily detected in collider experiments. One of the best strategies for detecting and characterizing the charged particles as well as neutral particles is to trigger on a hard-photon radiation. If kinematically accessible, such single-photon processes at$e^+e^−$colliders with polarized beams enable us to determine the spin of the (almost) invisible particles unambiguously through the threshold excitation pattern and characterize each scenario systematically by measuring the energy and scattering angle of the associated hard photon. Speaker: Xing Wang (University of Pittsburgh) • 105 A Model of Flavor and Flavor Changing In a recently proposed model of quark and lepton masses and mixing angles, all flavor mixing arises from the mixing of the Standard Model families with extra vectorlike fermions and ends up being controlled by a single 3x3 "master matrix". The model is therefore highly predictive. The model contains singlet scalars that mediate FCNC processes. It is shown that the resulting pattern of FCNC is also controlled by the master matrix, leading to some predictions and bounds.. Speaker: Prof. Stephen Barr (University of Delaware) • 106 Searches for new physics in final states with an electron/muon pair at CMS This talk reports on two recent searches in final states with an electron/muon pair carried out with the CMS detector at the LHC in proton-proton collisions at a center of mass energy of 8 TeV with an integrated luminosity of 19.7/fb. The first search addresses the possibility of lepton flavor violation (LFV) in interactions involving charged leptons. The invariant mass distribution of electron/muon pairs is examined for narrow resonances that may occur in R-parity violating Supersymmetry or theories featuring a LFV Z', and for edges that might indicate a mass threshold for the production of quantum black holes. With an invariant mass resolution of the electron/muon pair well below 10% up to the TeV range, the CMS detector is a powerful tool for such shape-based searches for new physics. The second presented result is a search for high-mass ditau events with leptonic decays to an electron/muon final state that is interpreted in terms of Z' resonances and large extra dimensions. In the absence of a significant deviation from the Standard Model expectation, upper limits are set on the signal cross section times branching ratio for the different signal models and translated into bounds on the model parameters. Speaker: Andreas Guth (Rheinisch-Westfaelische Tech. Hoch. (DE)) • 107 Hunting for Hierarchies in$\mathcal{PSL}_2(7)$We present a model with the family group$\mathcal{PSL}_2(7)$wherein the top quark hierarchy, through$SO(10)$and the Seesaw mechanism, is mapped onto the vacuum values of familon fields and transferred to the$\Delta I_{\rm w}=0$parameters of the$\nu$MSSM: the right-handed neutrino Majorana mass$\mathcal{M}$and the mu term. It predicts tribimaximal mixing, and a normal hierarchy for the light neutrinos. The familon vacuum is used to derive the supersymmetric$\mu$-masses of Higgs fields with family quantum numbers, as well as the Yukawa matrices of the quarks and leptons. We find, through the magic of$\mathcal{PSL}_2(7)$invariants, a$\mu$-matrix with a hierarchy of thirteen orders of magnitude. Only one Higgs field (per hypercharge sector) is light enough (with a$\mu$-mass ~ 10-100 GeV) to be destabilized by SUSY soft breaking at the TeV scale. Remarkably, their vacuum values generate unsupressed masses only for$t$,$b$, and$\tau$. Speaker: Michael Perez (University of Flordia) • 108 Anarchy In Unified Theories In Standard Model, massive fermions show strong hierarchy in their Yukawa couplings among the different generations and the CKM angles are related to the small mass ratios between fermions of different generations,that is why the quark mixing angles are quite small and the CKM matrix is almost close to unit matrix. In contrast Neutrino mixing angles are quite large. To incorporate all the masses and mixing, the mass matrices show strong hierarchy among the different generations. It is shown that the hierarchy among generations can arise as a consequence of mixing of ordinary fermions with three generations and other fermions, which have masses of order the GUT scale. Except the few parameters present in the model due to the mixing between light and super-heavy fermions, all the quark and lepton mass matrices are of order unity. It is exciting that even without the hierarchical structure of the mass matrices, large lepton mixing can also be reproduced. Speaker: shaikh saad (High Energy Theory) • 109 Spurion Analysis of the Little Flavor Model The Little Flavor model introduced a novel framework for understanding flavor: flavor structure is due to hierarchical breaking of the combination of vector-like symmetries and an approximate nonlinearly realized symmetry in the Higgs sector. While it was found that realistic mass hierarchies could result from physics at a few TeV, the underlying mechanism for appropriately suppressing flavor changing neutral currents (FCNC) was not understood. By carrying out a spurion analysis, we show that the suppression is due to the smallness of the Yukawa couplings in relation to the heavy vector fermion mass scale, in a way that is reminiscent of Extended Technicolor theories and is unlike Minimal Flavor Violation. This gives rise to small but potentially measurable FCNC and new Z' and W' bosons. The spurion analysis also allows us to discuss the radiative corrections to the light quark masses, a problem that plagued the original model. Speaker: Dorota Grabowska (INT/UW) • Cosmology III G26 ### G26 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Prof. Nobuchika Okada • 110 CMB Signals of a Hidden Dark Matter Sector We consider theories where dark matter is composed of a thermal relic of weak scale mass, whose couplings to the Standard Model (SM) are however too small to give rise to the observed abundance. Instead, the abundance is set by annihilation to hidden sector states that carry no charges under the SM gauge interactions. In such a scenario the constraints from direct and indirect detection, and from collider searches for dark matter, can easily be satisfied. If the hidden sector includes Goldstone bosons, fermions or vector gauge bosons, these particles can naturally be light, their masses being protected by symmetries. These states can then contribute to the total energy density in radiation, leading to observable signals in the cosmic microwave background (CMB). Furthermore, depending on whether or not the light hidden sector states self-interact, the fraction of the total energy density that free-streams is either decreased or increased, leading to characteristic effects on both the scalar and tensor components of the CMB anisotropy. In particular, we show that the locations of the CMB peaks are shifted, with the sign of the shift depending on whether or not these new light hidden sector states carry self-interactions. The magnitude of these signals depends on the number of light degrees of freedom in the hidden sector, and on the temperature at which it kinetically decouples from the SM. We consider a simple model that realizes this scenario, based on a framework in which the SM and hidden sector are initially in thermal equilibrium through the Higgs portal, and show that both the energy density and self-interaction signals can be compatible with recent Planck results, while large enough to be detected in upcoming experiments such as CMBPol and CMB Stage-IV. Speaker: Mr Sungwoo Hong (University of Maryland at College Park) • 111 A Tale of Two Timescales: Mixing, Mass Generation, and Phase Transitions in the Early Universe Light scalar fields such as string moduli, axions, and other possible dark-matter candidates play an important role in early-universe cosmology. However, a number of disparate considerations can significantly impact the late-time cosmological abundances of these fields. For example, in cases where the potentials (and therefore the masses) for such fields are generated dynamically --- such as during cosmological phase transitions --- the existence of an associated timescale can have significant repercussions. Moreover, in scenarios with multiple scalars, non-trivial mixing amongst the fields can also give rise to an effective timescale that modifies the resulting abundances. Previous studies have tended to focus on the effects of one or the other timescale in isolation. In this paper, by contrast, we consider a simple two-component toy model and examine what happens when both mixing and phase transitions are introduced together. In general, we find a number of surprising and dramatic features that result from the interplay between the two associated timescales. Speaker: Jeff Kost (University of Arizona) • 112 Baryogenesis via Mesino Oscillations We propose a model with a heavy O(TeV) coloured scalar which couples to the quarks via a singlet majorana fermion. After the chiral phase transition the heavy scalar binds with the SM quarks to form mesinos and anti mesinos. The mesino and antimesino undergo oscillations mediated via the singlet and these oscillations are the source of CP violation. The colored scalar then decays in a baryon number violating fashion giving baryogenesis. We explore the parameter space of the model putting bounds on the mass of the colored scalar and the singlet by requiring that they give us the correct baryon to entropy ratio Speaker: Akshay Ghalsasi (University of Washington) • 113 Sterile Neutrino dark matter produced after the QCD Phase Transition We study the production of sterile neutrinos in the early universe from$\pi \rightarrow l \nu_s$shortly after the QCD phase transition in the absence of a lepton asymmetry while including finite temperature corrections to the$\pi$mass and decay constant$f_{\pi}$. Sterile neutrinos with masses$ \lesssim 1 MeV$produced via this mechanism freeze-out at$T_f \simeq 10 MeV$with a distribution function that is highly non-thermal and features a sharp enhancement at low momentum thereby making this species \emph{cold} even for very light masses. Dark matter abundance constraints from the CMB and phase space density constraints from the most dark matter dominated dwarf spheroidal galaxies provide upper and lower bounds respectively on combinations of mass and mixing angles. For$\pi \rightarrow \mu \nu_s$, the bounds lead to a narrow region of compatibility with the latest results from the$3.55 \mathrm{KeV}$line. The non-thermal distribution function leads to free-streaming lengths (today) in the range of$\sim \mbox{few kpc}$consistent with the observation of cores in dwarf galaxies. For sterile neutrinos with mass$\lesssim 1 eV$that are produced by this reaction, the most recent accelerator and astrophysical bounds on$U_{ls}$combined with the non-thermal distribution function suggests a substantial contribution from these sterile neutrinos to$N_{eff}$. Speaker: Louis Lello (University of Pittsburgh) • 114 Tight Scrutiny of Electroweak Phase Transitions. The standard model cannot provide a first order Electro-weak phase transition needed to explain Baryogenesis. Extensions to the standard model need to take into account break down of perturbation theory at high temperatures. An all-order resummation is performed via "Ring corrections" to take into account "Daisy diagrams" but this is usually carried out in the high temperature small coupling limit. We extend such analysis to temperatures comparable to the EW scale as well as large(yet perturbative couplings). Speaker: Harikrishnan Ramani (Yang Institute Of Theoretical Physics) • 115 Electroweak phase transition and Higgs boson couplings in the scale-invariant two Higgs doublet model We revisit an electroweak phase transition in the scale-invariant two Higgs doublet model in light of 125 GeV Higgs boson. The analysis is conducted by using the finite temperature one-loop effective potential with thermal resummation. We also discuss its impact on the Higgs boson couplings. We find that the so-called sphaleron decoupling condition is more severe than the conventional one by about 20% in phenomenologically allowed regions. It is also found that even when the Higgs couplings to the gauge boson and fermions are the same as in the standard model, a large deviation may appear in the triple Higgs boson coupling due to nondecoupling effects in this model. Speaker: Ms Kaori Fuyuto (Nagoya University) • 116 Higgs Relaxation Leptogenesis The recent observation of a relatively light Higgs boson at the LHC suggests that the Standard Model potential rises relatively slowly at large vacuum expectation values, and may even develop a second minimum. In such cases, the Higgs boson may develop a large vacuum expectation value during inflation; subsequently, it will relax to its equilibrium value. During this epoch, the time-dependent Higgs condensate can create an effective chemical potential for the lepton number, leading to a generation of the lepton asymmetry in the presence of some large right-handed Majorana neutrino masses. The electroweak sphalerons redistribute this asymmetry between leptons and baryons, accounting for the observed cosmological matter-antimatter asymmetry. Speaker: Lauren Pearce (University of Minnesota) • Dark Matter III Convener: Arthur Kosowsky • 117 Baryonic Dark Matter I present an extension of the Standard Model in which baryon number is a local gauge symmetry that can be spontaneously broken at the low scale without introducing dangerous operators mediating proton decay. In this model, the dark matter candidate is a Dirac fermion with baryon number. I discuss the prospects for direct and indirect dark matter detection, as well as collider signatures of the model. Speaker: Michael Duerr (MPIK Heidelberg) • 118 Neutrino Masses and Sterile Neutrino Dark Matter from the PeV Scale The Higgs boson mass of 125 GeV is suggestive of superpartners at the PeV scale. We show that new physics at this scale can also explain the observed active neutrino masses via a modified, low energy seesaw mechanism and provide a sterile neutrino dark matter candidate with keV-GeV scale mass. These emerge in a straightforward manner if the right-handed neutrinos are charged under a new symmetry broken by a scalar field vacuum expectation value at the PeV scale. The dark matter relic abundance can be obtained through active-sterile oscillation, freeze-in through the decay of the heavy scalar, or freeze-in via non-renormalizable interactions at high temperatures. Speaker: Samuel Roland (University of Michigan) • 119 Conformal Inverse Seesaw and Warm Dark Matter In this work we discuss generic model building consequences in the conformal framework and demonstrate their implications in the conformal inverse seesaw on neutrino mass phenomenology and the dark matter abundance. We find that low energy particle physics observables favour a scenario with heavy pseudo-Dirac sterile neutrinos, which in the conformal framework conspire with the electroweak scale to generate keV scale warm Dark Matter. The mass scale relations provide naturally the correct relic abundance due to a freeze-in mechanism. We demonstrate in this work how scale symmetry decouples the right-handed neutrino mass scale and effective lepton number violation, as all fermionic mass scales arise as a result of Yukawa type interactions Speaker: Juri Smirnov (Max Planck Institute for Nuclear Physics) • 120 A Dark Side of Neutrino Mass We propose a simple scenario that directly connects the dark matter (DM) and neutrino mass scales. Based on an interaction between the DM particle$\chi$and the neutrino$\nu$of the form$\chi\chi\nu\nu/\Lambda^2$, the DM annihilation cross section into the neutrino is determined and a neutrino mass is radiatively induced. Using the observed neutrino mass scale and the DM relic density, the DM mass and the effective scale$\Lambdaare found to be of the order MeV and GeV, respectively. We construct an ultraviolet-complete toy model based on the inverse seesaw mechanism which realizes this potential connection between DM and neutrino physics. Speaker: Dr Wei-Chih Huang (University College London) • 121 Aspects of Lepton Flavored Dark Matter All matter in the Standard Model appears in three generations, with a flavor structure the origin of which is not well understood. This motivates the question whether distinct phenomenological features arise if dark matter (DM) also has a non-trivial flavor structure. In this talk I will review the experimental signatures of a scenario where DM carries lepton flavor. I will demonstrate that the generation of a lepton asymmetry at a high energy scale can also produce a DM asymmetry, which can strongly affect the sensitivity of direct detection experiments, and I will present novel signatures that can appear at colliders and in indirect detection experiments. Speaker: Can Kilic (University of Texas at Austin) • 122 Lepton-Flavored Dark Matter In this work, we try to simultaneously address two puzzles related to dark matter and flavor. The first is tension between the new physics scale suggested by the measured dark-matter relic density, O(100 GeV - 1 TeV), and the null results from direct-detection experiments which suggest a lower bound on the new physics scale of O(10 TeV). The second is tension between the strong constraints on lepton-flavor-violating processes involving electrons and the 3.6-sigma deviation of the muon g-2 from the standard model expectation which suggests a new-physics scale < O(1 TeV). Here, we suggest that these may be related. We consider a gauged lepton-flavor interaction coupling at tree level only to mu- and tau-flavored leptons and the dark sector. Dark matter thus has loop-suppressed couplings to quarks and electrons. We find that a gauged flavor interaction at a scale O(100 GeV - 1 TeV) can be compatible with the muon g-2, the relic density, direct detection, indirect detection, charged-lepton decays, neutrino trident production, and results from hadron and e+e- colliders. Speaker: Jennifer Kile (U Florida) • 123 Dark Matter in Leptophillic SUSY In this talk I discuss the phenomenology of the Leptophilic two-Higgs Doublet model and Leptophilic SUSY, and its implications for dark matter physics. Such models allow for viable dark matter candidates while offering interesting phenomenology in the extended Higgs sector. I review the constraints that these models must satisfy, and discuss its ability to explain anomalies such as the gamma ray excess from the galactic center. I also discuss the exciting possibilities with regards to future collider searches. Speaker: Mr David Feld (Rutgers) • 124 Neutrino Dark Matter in the Higgs triplet model The inability to predict neutrino masses and the existence of the dark matter are two essential shortcomings of the Standard Model. In this work we analyze the effects of introducing vectorlike leptons in the Higgs triplet model to provide a scenario that can explain both neutrino masses and provide a DM candidate. We investigate constraints, including the invisible decay width of the Higgs boson and the electroweak precision variables, and impose restrictions on model parameters. We analyze the effect of the relic density constraint on the mass and Yukawa coupling of dark matter. We also calculate the cross sections for indirect and direct dark matter detection and show our model predictions for the neutrino and muon fluxes from the Sun, and the restrictions they impose on the parameter space. With the addition of vectorlike leptons, the model is completely consistent with dark matter constraints, in addition to improving electroweak precision and doubly charged mass restrictions, which are rendered consistent with present experimental data. Speaker: Ms Sahar Bahrami (Concordia University) • Higgs III G30 ### G30 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Chien-Yi Chen (Brookhaven National Laboratory) • 125 Search for Higgs bosons beyond the standard model in b-jet final states at CMS After a Higgs boson with a mass near 125 GeV has been discovered, it is still unclear whether this is the Higgs boson predicted by the standard model (SM) or part of an extended Higgs sector, which is expected in various well-motivated beyond-the-SM models such as the minimal and next-to-minimal supersymmetric extensions (MSSM and NMSSM) of the SM. Direct searches for additional Higgs bosons are a promising way to answer this question. Recent results of searches for additional Higgs bosons with the CMS detector are presented, which are based on pp collision data collected at centre-of-mass energies of 7 and 8 TeV corresponding to integrated luminosities of 5/fb and 20/fb. Speaker: Gregor Mittag (né Hellwig) (Deutsches Elektronen-Synchrotron (DE)) • 126 Constraints on the GM model by current LHC data Based on latest LHC Higgs search results, we find constraints on theory parameters of the Georgi-Machacek Model. In particular, we obtain upper bounds on the triplet vacuum expectation value as a function of exotic Higgs masses and the mixing angle alpha between the two custodial singlets. We also scrutinize the small-mass region in the diphoton channel. Speaker: Prof. Cheng-Wei Chiang (National Central University) • 127 Higgs production in the Georgi-Machacek model through vector boson fusion We explore Higgs production via vector boson fusion in the Georgi-Machacek (GM) model. The GM model adds isospin triplet scalars to the SM while preserving custodial SU(2) symmetry. The model contains a custodial quintuplet of Higgs bosons which are phenomenologically distinct from the states of the SM or the 2HDM. The quintuplet is fermiophobic, making vector boson fusion the primary production mode. Using the MadGraph5_aMC@NLO framework, we produce differential distributions at NLO with parton shower matching. We find that NLO effects have a significant impact on the shape of the distributions for many observables. We also note that the ratio of the quintuplet state couplings to W versus Z bosons differs substantially from those of the SM, and that this may further impact the shape of the distributions. Speaker: Andrea Peterson (Carleton University) • 128 The low energy theories of the Higgs sector Effective field theory provides an excellent way to organize the modifications to the Standard Model Higgs properties, in the case of an extended Higgs sector. In this talk, we present the low energy theories for the Higgs sector for some of the most popular beyond the standard model UV completions. For brevity, we only consider the Higgs sector extended with a real singlet (xSM) and with a second doublet (2HDM). The results are simple, illustrative and provide valuable tools for studying the Higgs sector at LHC run II. Speaker: Daniel Egana (Rutgers University) • 129 CMS collaboration: Search for exotic Higgs bosons with the CMS detector The most recent results from CMS searches for heavy scalar (H) and pseudoscalar (A) Higgs bosons predicted in the minimal supersymmetric standard model (MSSM) and in the (2HDM) extensions of the standard model (SM) will be presented. These searches are based on a data sample of pp collisions collected with the CMS experiment at the LHC at a center-of-mass energy of s√=8 TeV and corresponding to an integrated luminosity of 19.5 fb−1. In particular, the presentation will focus on the search for a heavy Higgs decaying into a Z and a pseudoscalar A with a final state containing two leptons and two b-jets or two tau's. Speaker: Alexandre Jean N Mertens (Universite Catholique de Louvain (UCL) (BE)) • 130 The Hunt for the Rest of the Higgs Bosons We assess the current state of searches at the LHC for additional Higgs bosons in light of both direct limits and indirect bounds coming from coupling measurements of the Standard Model-like Higgs boson. Given current constraints, we identify and study three LHC searches that are critical components of a comprehensive program to investigate extended ￼electroweak symmetry breaking sectors: production of a heavy scalar or pseudoscalar with decay to t\bar{t}; b\bar{b} and t\bar{t} associated production of a heavy scalar or pseudoscalar with decay to invisible final states; and t\bar{b} associated production of a charged Higgs with decay to \bar{t}b. Systematic experimental searches in these channels would contribute to robust coverage of the possible single production modes of additional heavy Higgs bosons. Speaker: HAO ZHANG (University of California, Santa Barbara) • 131 Only one 125 GeV Higgs, is that all? Besides the SM-like Higgs boson discovery, it is also important to assess all possibilities for other Higgs-like states that are built in the extended Higgs sector and may have escaped detection at Run 1 of the LHC. One often considered the limit is the decoupling limit in which one scalar Higgs is SM-like and others are very heavy. A SM-like scalar Higgs boson can however also be obtained in the alignment limit without the masses of other Higgs being large. In this talk I address the seemingly extreme case in which the one scalar (h) is the SM-like 125 GeV state and a pesudoscalar (A) light enough that the SM-like state can decay into them. Identifying the precise region in which a sufficiently small hAA coupling occurs to escape the large Higgs invisible decay is my first goal. Following this challenging analysis, I will show that such light Higgs states are phenomenologically viable and can lead to interesting signatures. Part of the relevant parameter space is undergoing the tests with the existing LHC 8 TeV data. In addition, the contrast on the results achieved within the alignment limit and in the decoupling of heavier scalar states will be discussed. Speaker: YUN JIANG (UC Davis) • 132 Heavy Higgs Bosons at 14TeV and 100TeV As a landmark of BSM physics, the MSSM Higgs sector has been tested up to hundreds of GeV at the LHC, except for the moderatetan\beta$region. We present a study covering this region at the LHC and a next-generation pp-collider. We propose to search not only in channels with single Higgs production but also with associated Higgs productions. A multivariate method of Boosted Decision Tree is applied in collider physics. Speaker: Ms Ying-Ying Li (Hong Kong University of Science and Technology) • Neutrinos G27 ### G27 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Alexander Stuart • 133 Dynamical Pion Collapse and the Coherence of Neutrino Beams This talk will cover progress towards understanding the coherence properties of neutrino beams, using an open-quantum-systems approach to neutrino production. A new derivation of the generalized neutrino oscillation probability from arbitrarily prepared pions will be presented, followed by a calculation of the pion state that evolves through electromagnetic interactions with decay pipe gases. From these two ingredients, the full oscillation phenomenology of accelerator neutrino beams is derived without arbitrary scales or initial-state assumptions. Speakers: Benjamin Jones (MIT), Benjamin Jones (H. H. Wills Physics Laboratory-University of Bristol-Unknown) • 134 The latest result/analysis of Double Chooz Experiment Precise measurement of the neutrino mixing angle theta13 is the primary goal of the Double Chooz Experiment. Inverse beta decay process provides a unique signature of anti-neutrino interaction from the reactors, giving prompt signals from positron annihilation and delayed signals from neutron capture by either Gadolinium (Gd) or Hydrogen (H). In this talk, the latest Gd- and H-based analysis results from Double Chooz will be presented, including the detection efficiency evaluation, background estimates, energy calibration and oscillation results. Furthermore, the potential for sterile neutrino search will be shown. Speaker: Mr Guang Yang (Argonne/IIT) • 135 Standard and Non-standard Neutrino Oscillations at Daya Bay In this talk the three neutrino framework that describes the standard neutrino oscillations will be briefly introduced enphasizing on the role of the Daya Bay reactor neutrino experiment. After the introduction, the Daya Bay power to constraint charge current non-standard neutrino interactions (NSI) will be presented. The impact of the systematical error in the total normalization of the events on the constraints obtained will be discussed. Speaker: Dr David Vanegas Forero (Center for Neutrino Physics, Virginia Tech) • 136 Reconciling eV Sterile Neutrinos with Cosmological Bounds We propose a mechanism to reconcile eV sterile Neutrinos, suggested by short baseline experiments, with cosmological mass bounds. New self-interactions are neccessarily introduced for sterile neutrinos to suppress their production in the early Universe. Speaker: Dr Yong Tang (KIAS) • 137 Resonant Neutrino Self-Interaction in IceCube Recently IceCube experiment has revealed the spectrum of cosmic neutrinos in TeV-PeV range. However, null detection of 400-800 TeV neutrinos disagrees with a power law energy spectrum implied by the others. We interpret this "dip" feature as a hint of neutrino self-interactions. We investigate the possibility that well-motivated U(1)Lmu-Ltau model can explain the feature. We show that future (null-)detection of 400-800 TeV neutrinos can give us invaluable hints about structure of the neutrino sector. We also discuss its implication for CMB/BBN and supernova. Resonant neutrino self-interaction has a big impact on SN cooling. Speaker: Ayuki Kamada (University of California, Riverside) • 138 On neutrino and charged lepton masses and mixings: A view from the electroweak-scale right-handed neutrino model We present a model of neutrino masses within the framework of the EW-$\nu_R$model in which the experimentally desired form of the PMNS matrix is obtained by applying an$A_4$symmetry to the *Higgs singlet sector* responsible for the neutrino Dirac mass matrix. This mechanism naturally avoids potential conflict with the LHC data which severely constrains the Higgs sector, in particular the Higgs doublets. Moreover, by making a simple$ans\ddot{a}tz$we extract$\mathcal{M}_l {\mathcal{M}_l}^\dagger$for the charged lepton sector. A similar$ans\ddot{a}tz$is proposed for the quark sector. The sources of masses for the neutrinos are entirely different from those for the charged leptons and for the quarks and this might explain why$U_{PMNS}$is *very different* from$V_{CKM}$. Speaker: Trinh Le (University of Virginia) • 139 The improved bounds on the heavy neutrino productions at the 8 TeV LHC With the heavy Standard Model (SM) singlet neutrinos, the (inverse) seesaw mechanism provides us with a natural way to incorporate the neutrino mass in the SM. If the heavy neutrinos have their mass of the electroweak scale, they can be produced at the Large Hadron Collider (LHC) through their mixing with the SM light neutrinos. We investigate the heavy neutrino production processes at the LHC with a variety of initial states at the parton level, such as quark-quark annihilation, quark-gluon and gluon-gluon fusions, as well as the collision of proton with a photon radiated from the other proton, for the final states including up to two jets. We simulate signal events for the heavy neutrino productions for both pseudo-Dirac and Majorana cases. Comparing our simulation results with the current CMS and ATLAS data, we obtain the upper bound on the mixing angle between the heavy and SM light neutrinos. We find that the heavy neutrino production processes associated with two jets yield a sizable contribution to the total heavy neutrino production cross section and therefore, the upper bound on the mixing angle is improved from the one obtained in previous analysis. Speaker: Mr Arindam Das (University of Alabama) • 140 Heavy Neutrino Searches at Future Colliders We discuss the future prospects of heavy neutrino searches at future lepton colliders. In particular, we focus on the planned electron-positron colliders, operating in two different beam modes, namely,$e^+e^-$and$e^-e^-$. In the$e^+e^-$beam mode, we consider various production and decay modes of the heavy neutrino ($N$), and find that the final state with$e+2j+\not{\!E}$, arising from the$e^+e^-\to N\nu$production mode, is the most promising channel. However, since this mode is insensitive to the Majorana nature of the heavy neutrinos, we also study a new production channel$e^+e^-\to Ne^\pm W^\mp$, which leads to a same-sign dilepton plus four jet final state, thus directly probing the lepton number violation in$e^+e^-$colliders. In the$e^-e^-$beam mode, we study the prospects of the lepton number violating process of$e^-e^-\to W^-W^-$, mediated by a heavy Majorana neutrino. We use both cut-based and multivariate analysis techniques to make a realistic calculation of the relevant signal and background events, including detector effects. Speaker: Bhupal Dev (University of Manchester) • SUSY III 157 ### 157 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Sunghoon Jung • 141 Mini-Review: Physics with Electroweakinos Speaker: Stefania Gori • 142 Mono-Boson Search Strategies for Mass Degerate Particles New light states may be produced in abundance at LHC, however, if they are mass degenerate -with decay products that are soft they may very difficult to detect. Typically in order to detect these states one needs to trigger on initial-or final-state radiation. While analyses have focused on mono-jet and mono-photon triggers. I will argue that these these triggers can fall short, due to the large backgrounds and unfavorable pT distribution the IRS bosons. Instead, I argue that mono-w and Z triggers, with leptonic Z/W decays or fat jets may well provide the best search strategy. I will analyze the electroweak-ino sector of SUSY as an example case. Speaker: Linda Carpenter (Ohio State University) • 143 Probing Compressed SUSY spectra at the LHC I discuss methods that can be used to probe compressed Higgsinos and compressed Sleptons at the LHC. Speaker: Zhenyu Han (University of Oregon) • 144 New search strategies for well tempered neutralino dark matter at the LHC and beyond Supersymmetry with R parity provides a stable dark matter candidate. However, over much of the parameter space, the dark matter candidate does not freeze out to the observed relic abundance. One method to achieve the observed relic abundance relies on the co-annihilation of multiple, nearly-degenerate electroweakino states. This so-called well tempering evades traditional collider searches because the compressed spectrum leaves soft decay products. I outline a new strategy that takes advantage of this compressed spectrum and estimate its usefulness at the LHC and a future 100 TeV collider. Speaker: Bryan Ostdiek (University of Notre Dame) • 145 Using soft leptons to hunt quasi-degenerate higgsinos Naturalness arguments imply the existence of higgsinos lighter than 200-300 GeV. However, because these higgsinos are nearly mass degenerate, they release very little visible energy in their decays, and escape detection in traditional search channels. Prospects for detecting higgsino pair production via events with monojets or mono-photons from initial state radiation are also bleak because of signal-to-background rates typically at the 1% level. Here, we consider the possibilities of improving the LHC capability to probe quasi-degenerate higgsinos by utilizing soft daughter leptons from higgsino decays. Speaker: Azar Mustafayev (University of Hawaii) • 146 Long-Lived Superparticles with Hadronic Decays at the LHC Supersymmetry searches at the LHC are both highly varied and highly constraining, but the vast majority are focused on cases where the final-stage visible decays are prompt. Scenarios featuring superparticles with detector-scale lifetimes have therefore remained a tantalizing possibility for sub-TeV SUSY, since explicit limits are relatively sparse. Nonetheless, the extremely low backgrounds of the few existing searches for collider-stable and displaced new particles facilitates recastings into powerful long-lived superparticle searches, even for models for which those searches are highly non-optimized. In this paper, we assess the status of such models in the context of baryonic R-parity violation, gauge mediation, and mini-split SUSY. We explore a number of common simplified spectra where hadronic decays can be important, employing recasts of LHC searches that utilize different detector systems and final-state objects. The LSP/NLSP possibilities considered here include generic colored superparticles such as the gluino and light-flavor squarks, as well as the lighter stop and the quasi-degenerate Higgsino multiplet motivated by naturalness. We find that complementary coverage over large swaths of mass and lifetime is achievable by superimposing limits, particularly from CMS's tracker-based displaced dijet search and heavy stable charged particle searches. Adding in prompt searches, we find many cases where a range of sparticle masses is now excluded from zero lifetime to infinite lifetime with no gaps. In other cases, the displaced searches furnish the only extant limits at any lifetime. Speaker: Zhen Liu (U of Pittsburgh) • 147 Search for stealth supersymmetry in events with jets, either photons or leptons, and low missing transverse momentum in pp collisions at 8 TeV Supersymmetry (SUSY) can simultaneously solve the hierarchy problem, allow unification of the fundamental interactions, and provide a candidate for dark matter. Most searches for SUSY focus on the presence of large missing transverse energy (MET) carried away by the lightest SUSY particle. Recent high-MET searches at the CERN LHC have not yet found evidence for SUSY. Therefore, it is important to study well-motivated alternatives with low-MET, such as models characterized by R-parity violation, compressed spectra, and hidden valleys. In particular, the "stealth SUSY" model yields a low-MET signature while conserving R-parity by means of a new hidden sector in which SUSY is approximately conserved. I will present recent CMS searches for stealth SUSY using jets, leptons or photons, and no MET. Speakers: Benjamin Taylor Carlson (Carnegie-Mellon University (US)), Benjamin Taylor Carlson (Carnegie-Mellon University (US)) • Top G28 ### G28 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Gregory Mahlon • 148 Probing top-quark couplings at NLO accuracy Computations at next-to-leading order (NLO) in the standard model offer new technical challenges in the presence of higher dimensional operators. I will present a framework that, starting from the top-quark effective field theory, allows one to make predictions for cross sections as well as distributions in a fully automatic way. Therefore in this framework one can easily obtain NLO predictions for BSM effects in the top-quark sector. I will present several applications, including processes involving anomalous top-quark couplings, top FCNC couplings, and top couplings with dark matter particles. Speaker: Cen Zhang (Brookhaven National Laboratory) • 149 Top quark pair production measurements using the ATLAS detector at the LHC Measurements of the inclusive top quark pair production cross sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented. The most precise result requires opposite sign electrons and muons and uses the full data-set at a centre-of-mass energy of 7 and 8 TeV. In addition, differential measurements of the top transverse momentum and kinematic properties of the top-anti-top pair are discussed. These measurements, including results using boosted tops, probe our understanding of top pair production in the TeV regime. The results, unfolded to particle and parton level, are compared to recent Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers and NLO QCD calculations. In addition, measurements of the production of top quark pairs in association with gauge bosons or jets are presented. Speaker: Ki Lie (Univ. Illinois at Urbana-Champaign (US)) • 150 Top quark pair properties using the ATLAS detector at the LHC The latest measurements of the properties of the top quark using the ATLAS experiment are presented. The top quark mass is one of the fundamental parameters of the Standard Model. A measurement based on a multi-dimensional template fit that can constrain the uncertainties on the energy measurements of jets is presented and combined with a measurement using dilepton events. In addition, novel measurements aiming to measure the mass in a well-defined scheme are presented. The top quark pair charge asymmetry is an asymmetry predicted to occur beyond leading-order QCD in the Standard Model, and may be significantly enhanced by the presence of new physics. The ttbar production charge asymmetry is measured inclusively and differentially using the 7 and 8 TeV ATLAS datasets. Making use of the large number of top quark pairs collected, we also present measurements of the spin correlation between top and anti-top quarks and discuss their sensitivities to new physics. A search for flavour changing neutral current processes in top quark decays is also presented. Speaker: Bruno Galhardo (Universidade de Coimbra (PT)) • 151 New measurements of ttW and ttZ at CMS New measurements of top quark pair production in association with a W or Z boson are presented, using 19.5 fb−1 of 8 TeV pp collision data collected by the CMS experiment at the CERN LHC. Final states with opposite-sign, same-sign, three, and four charged leptons plus b-tagged jets are examined. Signal ttW and ttZ events are identified by reconstructing the top quark pair, yielding the most sensitive and precise measurements of these processes to date. New limits are also placed on five anomalous dimension-six operators which would affect the ttW and ttZ cross sections. Speaker: Andrew Brinkerhoff (University of Notre Dame (US)) • 152 Single Top quark production cross section and properties using the ATLAS detector at the LHC Measurements of single top-quark production in proton proton collisions at 7 and 8 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. The single top-quark and anti-top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. In addition, a measurement of the production cross section of a single top quark in association with a W boson is presented. All measurements are compared to state-of-the-art theoretical calculations and the CKM matrix element |Vtb| is determined. In addition, the s-channel production is explored and limits on exotic production in single top quark processes are discussed. This includes the search for flavor changing neutral currents and the search for additional W’ bosons or a search for monotops. Speaker: Kevin Sapp (University of Pittsburgh (US)) • 4:00 PM Coffee Break Benedum Hall G ### Benedum Hall G #### University of Pittsburgh Pittsburgh, PA 15260 • B Physics G27 ### G27 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Amarjit Soni (BNL) • 153 CP violation in B and Bs decays The LHCb collaboration has recently released a number of new and updated measurements of the CP violating angles β and φs using the full 2011 and 2012 datasets. These CP violating parameters, which are sensitive to possible BSM physics, are observable in the interference between mixing and b->ccs decays of B and Bs mesons, respectively. LHCb has measured sin(2β) in an analysis of B -> J/ψ KS and multiple measurements of φs in analyses of Bs -> J/ψ φ, Bs -> J/ψ π π, and Bs -> Ds Ds. The effective angle φs is also measured in the rare decay Bs -> φ φ, which proceeds through a suppressed b->sss penguin diagram, and is thus also sensitive to new physics through the decay amplitude. Analyzing the interference between neutral meson mixing and decay necessitates a flavor-tagged lifetime analysis. This talk will present the latest results from LHCb on these channels. Speaker: Mr Jack Wimberley (University of Maryland, College Park) • 154 The shape of new physics in rare B decays Flavor physics offers a formidable window into new physics. In particular rare B-meson decays have received a great share of attention due to recent anomalous measurements. The customary Effective Field Theory scheme parametrizes deviations from the Standard Theory at the B meson scale with operators invariant under electro-magnetism and the strong interactions. However, if the scale of new physics lies above the electro-weak scale, the customary operators must originate from electro-weak invariant ones. This implies a sizable simplification of the analysis via a reduction of the independent operators. On the other hand, one of the most prominent anomalies is the measured ratio of the decays of a B meson to a kaon, a muon and an anti-muon vs a kaon, an electron and a positron. This ratio differs from one, hinting at lepton universality violation. This is a rather unexpected result, specially in the present absence of lepton flavor violation. We will explore the naturalness of the former without the latter both in an EFT and with a specific model. Speaker: Rodrigo Alonso (UC San Diego) • 155 Studies of charmless B decays at LHCb Decays of b-hadrons to suppressed ‘charm-less’ final states are an attractive avenue to test the Standard Model, as they typically proceed via 'penguin' loop diagrams where new physics may enter virtually, and are also sensitive to CP violation via the interference between these penguin processes and the tree-level processes. We present the latest studies of such decays on the Run 1 dataset of the LHCb experiment. Speaker: Daniel Patrick O'Hanlon (University of Warwick (GB)) • 156 Simultaneous Explanation of the$R_K$and$R(D^{(∗)})$Puzzles At present, there are several hints of lepton flavor non-universality. The LHCb Collaboration has measured$R_K$≡$B(B^+→K^+μ^+μ^−)/B(B^+→K^+e^+e^−)$, and the BaBar Collaboration has measured$R(D^{(∗)})$≡$B(\bar{B}→D^{(∗)+}τ^−\bar{ν}_τ)/B(\bar{B}→D^{(∗)+}ℓ^−\bar{ν}_ℓ)(ℓ=e,μ)$. In all cases, the experimental results differ from the standard model predictions by 2-3$σ$. Recently, an explanation of the$R_K$puzzle was proposed in which new physics (NP) generates a neutral-current operator involving only third-generation particles. Now, assuming the scale of NP is much larger than the weak scale, this NP operator must be made invariant under the full$SU(3)_C×SU(2)_L×U(1)_Y$gauge group. In this Letter, we note that, when this is done, a new charged-current operator can appear, and this can explain the$R(D^{(∗)})$puzzle. A more precise measurement of the double ratio$R(D)/R(D^{(∗)})$can rule out this model. Speaker: Shanmuka Shivashankara (University of Mississippi) • 157 AdS/QCD predictions for$B\to K^* \mu^+\mu^-$decay rate and isospin/forward-backward asymmetries. We use the light front wavefunction predicted by holographic anti–de Sitter/Chromodynamics (AdS/QCD) for$K^*$vector meson to obtain the form factors for exclusive dileptonic rare$B \to K^* \mu^+ \mu^-$decay. Consequently, the differential decay rate, isospin and forward-backward asymmetry distributions for this transition mode are obtained and compared with the latest available experimental data. We conclude that a negative new physics contribution to the Wilson coefficient$C_9$can enhance the agreement with data for all three observables. Speaker: Mohammad Ahmady (Mount Allison University) • 158 Measurement of the CKM angle$\gamma$at LHCb The weak phase$\gamma$is one of the least well-determined CKM parameters. It can be measured using time-independent decay rates, such as those of$B^+ \to D K^+$with$D \to K^0_s h h$, or by time-dependent studies, as in$B^0_s \to D_s^{\mp} K^{\pm}$decays. The precise determination of$\gamma$is one of the most important goals of LHCb. Several recent time-independent and time-dependent measurements of$\gamma$will be review together with the result of their combination, used to achieve the best accuracy on$\gamma$. Finally the first observation of the decay mode$B^0_s \to D_s^{*\mp} K^{\pm}$will be presented. The first observation of this mode is particularly relevant since it will be used, in the future, for a new time-dependent measurement of$\gamma$that could be added to the$\gamma$combination. Speaker: Dr alessandro bertolin (LHCb - INFN (Padova)) • 159 New physics searches, spectroscopy and decay properties of b-hadrons with the ATLAS experiment Latest results in the ATLAS programme of searches and precision measurement of heavy hadrons are presented. It includes observation of an excited B_c(2S) state, measurement of the B_c meson decays, as well as new decay modes of b-hadrons and search for New Physics signatures in processes that are naturally suppressed in the Standard Model. We present the latest search for rare B_s -> mu+mu- decay and angular analysis of the semileptonic rare decay B_d -> K*mu+mu- and an updated study of mixing and CP violation in the Bs system with full ATLAS Run-1 data. Speaker: Steffen Maeland (University of Bergen (NO)) • BSM IV G31 ### G31 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Zhenyu Han (Harvard University) • 160 The Mu2e Experiment at Fermilab The Mu2e Experiment at Fermilab will search for coherent, neutrinoless conversion of muons into electrons in the field of a nucleus with a sensitivity improvement of a factor of 10,000 over previous experiments. Such a lepton flavor-violating reaction probes new physics at a scale inaccessible with direct searches at either present or planned high energy colliders. The experiment both complements and extends the current search for muon decay to electron+gamma at MEG and searches for new physics at the LHC. We will present the physics motivation for Mu2e, the design of the muon beamline and the detector, and the current status of the experiment Speaker: Kevin Lynch (York College/City University of New York) • 161 A Bottom-Up Approach to Lepton Flavor and CP Symmetries We perform a model-independent analysis of the possible residual Klein and generalized CP symmetries associated with arbitrary lepton mixing angles in the case that there are three light Majorana neutrino species. This approach emphasizes the unique role of the Majorana phases and provides a useful framework in which to discuss the origin of the Dirac CP phase in scenarios with spontaneously broken flavor and generalized CP symmetries. The method is shown to reproduce known examples in the literature based on tribimaximal and bitrimaximal mixing patterns, and is used to investigate these issues for the case of a particular (GR1) golden ratio mixing pattern. Speaker: Alexander Stuart (SISSA) • 162 Searches for excited leptons at CMS According to today's knowledge, the leptons belong to the fundamental constituents of matter. However, it is possible that a further, so far hidden, lepton substructure exists. In such a scenario it would be possible to excite leptons to a heavier state. Excited leptons could then decay under the radiation of a photon or a weak gauge boson. The talk presents the search for single excited electrons and muons being produced in association with a lepton of the same flavour. For the first time at the LHC, not only the usual benchmark channels with two leptons and a photon in the final state are presented, but also the searches arising from Z-boson radiation are considered. The resulting 4-leptons and 2-leptons+jets signatures can efficiently be reconstructed with dedicated tools and allow to access and probe a much wider parameter space. The analyses are based on 20/fb of CMS data that were taken in 2012 at sqrt(s)=8 TeV. Speaker: Matthias Klaus Endres (Rheinisch-Westfaelische Tech. Hoch. (DE)) • 163 vector like leptons at LHC The performance of LHC and the results already achieved have been outstanding. The lightest Higgs scalar boson mass in supersymmetry can be raised significantly by extra vector-like quark and lepton supermultiplets with large Yukawa couplings but dominantly electroweak-singlet masses. We are interested in a model consisting of a${\bf 10} + {\bf \overline{10}}$of$SU(5)$. The non-MSSM particles in this case consist of charge$+2/3$quarks$t'_{1,2}$, a charge$-1/3$quark$b'$, and a charged lepton$\tau'$, and their scalar partners. We assumed that the mixing of the new fermions with Standard Model fermions is large enough to provide for prompt decays. Mixing with the third Standard Model family are considered, for which the constraints are much easier to satisfy. \\ We gave attention to the vector like lepton$\tau'$.$\tau'$can decay to$W\nu$,$Z\tau$, and$h^0 \tau$. Because there is only one relevant Yukawa mixing term, the branching ratios depend only on$m_{\tau'}$. The largest branching ratio for$\tau'$is always to$W\nu$. The most immediately relevant searches at hadron colliders will be in the mass range of$m_{\tau'}$just above 100 GeV, where the electroweak pair-production cross-section can be sufficiently large. We have shown that there are certain multilepton channels with a good possibility to observe desired signal over the backgrounds at 13 TeV. In order to do this we have implemented particular cuts to select events that are useful. We also considered some of the more optimistic scenarios where one of the branching ratio to$W\nu$,$Z\tau$, and$h^0\tau$are close to 1. Speaker: Ms nilanjana kumar (Geaduate student) • 164 Heavy Type III Seesaw Leptons at NLO in QCD In the context of the Type III Seesaw Mechanism, we present the next-to-leading order (NLO) in QCD corrections to the pair production of heavy leptons (both charged and neutral currents) in hadron collisions. Residual theoretical uncertainties are discussed. Speaker: Richard Ruiz • 165 Lepton Number Violation and Leptogenesis Leptogenesis provides an elegant unified framework to account for both the observed matter-antimatter asymmetry in the Universe and the smallness of the light neutrino masses. Low-scale seesaw models give an opportunity to test this idea in foreseeable laboratory experiments at the Energy and Intensity frontiers. We discuss one such class of models, based on a TeV-scale type-I seesaw mechanism naturally embedded in a Left-Right symmetric framework, and derive the leptogenesis constraints on the mass of the right-handed gauge boson. Speaker: Chang-Hun Lee (University of Maryland) • 166 The signal strength of the pseudo scalars in the model of electroweak-scaled right-handed neutrinos at the LHC We analyze and compute the signal strengths of pseudo scalars in the model of electroweak scaled right-handed neutrinos ($EW\nu_R$) model. The signal strengths are investigated in various major channels at LHC,$\gamma\gamma$, VV, and b$\bar{b}$. By comparing with the experimental results, we could have some excluded regions on the masses of pseudo scalars in our model in two particular parameter spaces . We also show an interesting decay mode which mimics the WW process. From that, an upper limit for coupling of a singlet with right-handed doublets is imposed. Speaker: vinh hoang (university of virginia) • BSM V 157 ### 157 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Azar Mustafayev (University of Hawai'i at Manoa (US)) • 167 Search for vector-like quarks at the LHC using the CMS detector We present recent results from the CMS experiment of searches for massive vector-like top and bottom quark partners using data collected in proton-proton collisions at centre-of-mass energy of sqrt(s)=8 TeV. These partners can be found in models addressing the hierarchy problem to stabilize the mass of the Higgs boson. The searches span a range of final states, from multi-lepton to entirely hadronic. All observations are consistent with the standard model, and limits are set on the production cross sections of the vector-like quarks. Speaker: Devdatta Majumder (University of Kansas (KU)) • 168 Searches for vector-like quarks with the ATLAS detector at the LHC The naturalness argument for theories beyond the Standard Model supports the presence of fermionic top/bottom quark partners, usually referred to as vector-like quarks (VLQs), to cancel mass divergence for the Higgs boson. Searches for vector-like quarks have been performed in various final states with leptons, jets and missing transverse momentum at the ATLAS experiment. This talk presents recent VLQ searches at ATLAS with LHC Run 1 data. Speaker: Ruchika Nayyar (University of Arizona (US)) • 169 The Oddest Little Higgs: Top partners decaying into jets The phenomenology of typical charge 2/3 top partners is determined by their decays T -> th, T -> tZ, T -> bW. Recent CMS and ATLAS searches have bounded the mass of such a top partner to be greater than ~700 GeV. We consider a Little Higgs model in which the quadratically divergent top loops are cancelled by a single top partner which is odd under a parity that forbids the couplings responsible for the standard decays. Instead, the top partner decays into third generation fermions and scalars, and the lightest odd scalars decay into light jets via small parity-violating couplings. This scenario has much in common with R-Parity violating SUSY. We find that RPV gluino searches severely constrain the parameter space of such models, but there exists a compressed window which allows for top partners lighter than the typical 700 GeV bound. Speaker: Jack Collins (urn:Google) • 170 Extra dimensions versus supersymmetry at the LHC Non-minimal universal extra dimensions (nmUED) involve the choice of boundary localized kinetic terms (BLKT) for the 5 dimensional gauge bosons and fermions. We find that with suitable choice of these parameters needed to explain the current Higgs data, the BLK terms removes the approximate degeneracy of the KK mass spectrum, and the pair productions of the level-1 quarks and gluons give rise to hard jets, lepton and large missing energy. Thus the LHC will not be able to distinguish between the supersymmetry and extra dimensions, and the production of the 2nd KK excitation will be the key for such a distinction. Speaker: Prof. Satyanarayan Nandi (Oklahoma State University) • 171 Discovery opportunity of new physics with M2 variables I will discuss discovery potential of new physics at hadron colliders using the recently proposed on-shell constrained$M_2$variables. Particular focus is upon new physics signatures in the top quark sector, for which regular pair-produced top quarks are dominant background. The relevant signal processes are featured by an *asymmetric* event topology, whereas top quark pairs are *symmetric*. I will start with a brief introduction on the on-shell constrained$M_2$variables, and then design the kinematic variables under the assumption of$t\bar{t}$event topology, evoking some contradiction in relevant observables. To demonstrate how the technique works, I will take a couple of examples: 1) supersymmetric top partner search and 2) light dark force carrier search. Speaker: Doojin Kim (University of Maryland) • 172 Searches for new physics in diboson resonances and other signatures with the ATLAS detector at the LHC Many extensions to the Standard Model predicts new particles decaying into two massive bosons (WW, WZ, ZZ and HH). Searches for such diboson resonances have been performed in final states with different numbers of leptons and jets including fat-jets with jet substructure. Searches for new physics in other final states are also carried out. This talk summarizes ATLAS searches for diboson resonances and other new physics signatures with LHC Run 1 data. Speaker: Mr Campoverde Angel (Stony Brook University) • 173 Search for heavy resonances in diboson final states with the CMS detector at LHC New results on searches for heavy resonances decaying to pairs of Standard Model bosons (WW, WZ, ZZ, WH, ZH, HH) based on the full dataset (L = 19.7fb-1) of proton-proton collisions at sqrt(s) = 8 TeV collected by the CMS detector at the LHC are presented. Several New Physics scenarios including extra dimensions, composite Higgs models, and the recently proposed heavy vector triplet (HVT) simplified model predict the existence of Beyond Standard Model (BSM) resonances that have enhanced couplings to boson pairs. These searches are particularly challenging, since for large resonance masses the two bosons are highly energetic ("boosted") and the final decay products difficult to separate. This requires the use and development of dedicated techniques such as jet substructure identification, novel b-tagging algorithms, and special tau reconstruction and lepton isolation approaches. Upper limits are set on the production cross section of BSM particles decaying to a pair of vector bosons. In addition, a common interpretation of the results in the HVT model is presented, which allows direct comparison of the sensitivity of the different channels. Speaker: Jennifer Ngadiuba (Universitaet Zuerich (CH)) • 174 Searches for resonant pair production of Higgs bosons using the CMS detector Searches for resonant pair production of Higgs bosons at the LHC using the CMS apparatus through various decay channels are presented. The analyses use Run I pp collision data recorded at sqrt(s) = 8 TeV. Upper limits on the production cross section of massive resonances between 250 GeV and 1.1 TeV are reported, and constraints on theories with extended Higgs sectors and Randall Sundrum dimensions are placed. Speaker: Souvik Das (University of Florida (US)) • Dark Matter IV G29 ### G29 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Brooks Thomas (University of Hawaii) • 175 Non-Abelian Darkness We propose a new alternative to the Cold Dark Matter scenario, in which the Dark Sector contains a Dark Matter particle charged under the Standard Model SU(2) gauge group and also charged under an unbroken SU(N) dark gauge group. We focus on dark gauge couplings that are much smaller than the SM gauge group couplings. In this limit the confinement scale is negligibly small and the dark gauge bosons are a new type of relativistic degree of freedom during all times in the cosmological history. We discuss the effects of the dark gauge bosons to the CMB and also show that the interactions between Dark Matter and the dark gauge bosons give rise to a new regime in the evolution of Dark Matter overdensities. We also briefly discuss how this model alleviate tensions between Planck and Large Scale Structure data. Speaker: Gustavo Marques Tavares (Boston University) • 176 Cosmological Constraints on Dynamical Dark Matter Dynamical dark matter (DDM) is an alternative framework to the more typical stable dark matter scenario. Instead of imposing stability of one or several particles that constitute the relic dark matter abundance, we consider many different particles decaying with less stable lifetimes while balancing their respective abundances in order to provide for an ensemble that acts as a phenomenologically viable dark matter candidate. Given an ensemble of particles, each with a unique mass, width and abundance, the total DM density will have a non-trivial time dependence and produce distinct astrophysical signatures. Previous work has investigated DDM constraints for an ensemble embedded within a bulk axion model and DDM signals in the observed positron fraction given a generic ensemble. In this work, we want to generalize cosmological and astrophysical constraints on a generic DDM ensemble. Speaker: Mr Patrick Stengel (University of Hawaii) • 177 Unitarity and Bound State Dark Matter The impact of unitarity constraints on a few Dark Matter portals as well as their physical meaning is briefly discussed. In regions of the parameter space where perturbative unitarity is violated, Dark Matter will form "mesonic" bound states that decay to Standard Model particles. Investigating the formation (and fate) of these bound states allows for a better understanding of the Dark Matter depletion mechanisms. Speaker: sonia el hedri (JGU Mainz) • 178 UltraViolet Freeze-in If dark matter is thermally decoupled from the visible sector, the observed relic density can potentially be obtained via freeze-in production of dark matter. Typically in such models it is assumed that the dark matter is connected to the thermal bath through feeble renormalisable interactions. Here, rather, we consider the case in which the hidden and visible sectors are coupled only via non-renormalisable operators. This is arguably a more generic realisation of the dark matter freeze-in scenario, as it does not require the introduction of diminutive renormalisable couplings. We examine general aspects of freeze-in via non-renormalisable operators in a number of toy models and present several motivated implementations in the context of Beyond the Standard Model (BSM) physics. Specifically, we study models related to the Peccei-Quinn mechanism and$Z'$portals. Speaker: Fatemeh Elahi (University of Notre Dame) • 179 Higgs portals to galactic center pulsar collapse Asymmetric fermionic dark matter coupled to the Standard Model through a MeV-scale Higgs portal mediator may be destroying pulsars at the center of the Milky Way. This talk reviews the recently uncovered galactic center missing pulsar anomaly, determines maximum pulsar age curves for asymmetric Higgs portal dark matter in the Milky Way (maximum pulsar age increases as dark matter halo density decreases), and looks at complementarity signals of pulsar collapsing dark matter at direct detection experiments and the LHC. Speaker: Joseph Andrew Bramante (University of Notre Dame (US)) • 180 Vector Dark Matter via Higgs Portal We discuss options and challenges associated with building viable models of Vector Dark Matter which interact with the Standard Model via the Higgs boson. The primary focus is to examine an effective operator as well as its possible UV completion where the portal is generated radiatively. Bounds and future sensitivities by collider and direct detection experiments will also be considered. Speaker: Anthony DiFranzo (UC Irvine / Fermilab) • 181 Dark matter explained through two distinct ideas related to Higgs The existence of dark matter is now well established fact. In this talk, I will talk about two distinct possibilities of dark matter. In the first case, the dark matter is assumed to be the ordinary matter in a “parallel Universe”. Our Universe and the parallel Universe are described by their own nonabelian gauge symmetries which forbid any kinetic mixing between them. However, the quartic Higgs interactions involving Higgs fields between the two Universes are allowed by the symmetries of the model. The ensuing mixing between the two lightest Standard Model like Higgses gives rise to interesting signatures at the proposed international electron-positron collider (ILC) specially in the case when mass splitting between the two surviving light Higgs bosons are small ( ∼ 100 MeV) so that they cannot be resolved at the LHC. In the totally different scenario, we show that a neutral scalar field,$\sigma$, of two Higgs doublet extensions of the Standard Model incorporating the seesaw mechanism for neutrino masses can be identified as a consistent$\it warm$dark matter candidate with a mass of order keV. The relic density of σ is correctly reproduced by virtue of the late decay of a right-handed neutrino N participating in the seesaw mechanism. Constraints from cosmology determine the mass and lifetime of N to be M_N = 25 GeV - 20 TeV and$\tau_N$= (10^{-4} - 1) sec. This model can also explain the 3.5 keV X-ray anomaly in the extra-galactic spectrum that has been recently reported in terms of the decay$\sigma\to\gamma\gamma$. Speaker: Shreyashi Chakdar (oklahoma state university) • 182 Scalar Dark Matter Mediated via Colored Scalar Dark matter is one of the major puzzles in our understanding of physics today where we expect the solution to be within the reach of our current theoretical knowledge of field theory and experimental reach. With LHC run-II scheduled for 2015, searches for accessible dark matter models is a major concern. In this work we consider the simplest dark matter model, an inert scalar with no Standard Model charges. Interactions of this scalar with Standard Model particles can proceed through the Higgs boson and such models have been extensively studied recently under the category of Higgs-portal models. The singlet scalar can also interact with SM particles via a colored charged scalar mediator. The interaction between the two types of scalars can proceed via a 4-point vertex without need for any additional symmetries. Such a colored scalar particle is predicted in many UV models for example GUT-flavor theories, R parity violating SUSY and some extra dimensional models and is already a part of the LHC BSM searches. We study this simplified model for various color representations of the mediating scalar and find constraints from relic density and direct detection on the couplings and masses of the colored scalar and DM. We find that the relic density constraints are satisfied for most of the parameter space where the singlet scalar is heavier than the colored mediator. In a simplified model framework, we search for constraints on a colored scalar particle at LHC and find that the gluon fusion to scalar pair production process constraints the scalar mass to be above 220\, GeV . Constraints are also obtained on the coupling between the dark matter and gluons in the effective interaction framework from monojet process. Speaker: Gaurav Mendiratta (Indian Institute of Science, Bangalore,India) • Electroweak G28 ### G28 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Cen Zhang (Brookhaven National Laboratory) • 183 Parton distributions and the W mass measurement We examine the sources of parton distribution errors in the W mass measurement, and point out shortcomings in the existing literature. Optimistic assumptions about strategies to reduce the error by normalizing to Z observables are examined and found to rely too heavily on assumptions about the parametrization and degrees of freedom of the parton distribution functions (PDFs). We devise a strategy to combine measurements as efficiently as possible using error correlations to reduce the overall uncertainty of the measurement, including Z data, and estimate a PDF error of$^{+10}_{-12}$MeV is achievable in a W mass measurement at the LHC. Further reductions of the W mass uncertainty will require improved fits to the parton distribution functions. Speaker: Prof. Zack Sullivan (Illinois Institute of Technology) • 184 Electroweak Corrections at the LHC Electroweak (EW) corrections at the LHC can be enhanced at high energies due to soft/collinear radiation of W and Z bosons, being dominated by Sudakov-like corrections in the form of$\alpha_W^l\log^n(Q^2/M_W^2)\;(n\le 2l-1, \alpha_W = \frac{\alpha}{4\pi\sin\theta_W^2})$when the energy scale$Q$enters the TeV regime. Thus, the inclusion of EW corrections in LHC predictions is important for the search of possible new physics in tails of distributions. EW corrections should also be taken into account in virtue of its comparable size ($\mathcal{O}(\alpha)$) to that of higher order QCD corrections ($\mathcal{O}(\alpha_s^2)$). We calculated the next-to-leading-order (NLO) weak corrections to the neutral-current (NC) Drell-Yan process, top-quark pair production and dijet producion, respectively, and implemented them in the Monte-Carlo program MCFM. This enables a combined study with the corresponding NLO QCD corrections. We provide both the full NLO weak corrections and their weak Sudakov approximation valid at high energies. The latter is often used for a fast evaluation of weak effects, and having the exact result available as well allows to quantify the validity of the Sudakov approximation. Speaker: Jia Zhou (SUNY Buffalo) • 185 Electroweak Corrections to Vector Boson + b-jet Production A precise determination of V+b processes (V=Z, photon) at hadron colliders opens the possibility of measuring the b-quark PDF at the LHC. In this context, we have computed the one-loop electroweak (EW) corrections for the production of a b-jet in association with a Z boson in hadronic collisions. In the interest of accuracy and future developments, we retain the b-quark mass both in the initial and final states. For a comprehensive phenomenological study, we compare EW and QCD corrections under the same assumptions, and we estimate the residual level of theoretical systematic uncertainty. Speaker: Steven Honeywell (Florida State University) • 186 Recent electroweak results from ATLAS ATLAS measurements of multi-boson production processes involving combinations of up to three W, Z and isolated photons are summarized. Production processes sensitive to vector-boson fusion and vector-boson scattering such as electroweak production of single Z and W bosons associated with two forward jets and the same-sign WW production at 8 TeV pp collisions are also presented and compared to Standard Model expectations. A measurement of the inclusive 4 lepton mass spectrum from 80 to 1000 GeV is presented, where several distinct physics processes are involved: the single Z resonant process, the Higgs production at 125 GeV, as well as continuum ZZ production processes with qqbar and gg initial states. Speaker: Aparajita Dattagupta (Indiana University (US)) • 187 ATLAS measurements of vector boson production Measurements of vector boson production allow tests of perturbative and non-peturbative QCD and of electroweak couplings, as well as being important backgrounds in measurements of Higgs properties and searches for new resonances. Six of the latest results from ATLAS in this area will be presented including measurements of the W cross-section in association with jets, which tests QCD in a multi-scale environment and the Z transverse momentum distribution, which is sensitive to soft resummation effects as well as hard jet emissions. The agreement with the latest theoretical predictions will be discussed. Speaker: Samuel Webb (University of Manchester (GB)) • Higgs IV G30 ### G30 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Ms Peisi Huang (University of Wisconsin (US)) • 188 Measurements of the properties of the Higgs boson using the ATLAS Detector A review of Run 1 results on the mass, spin CP properties, off-shell couplings, and differential cross section measurements of the Higgs boson using the ATLAS detector will be presented. Speaker: Jordan S Webster (University of Chicago (US)) • 189 Search for Higgs Bosons produced in association with top quarks with the ATLAS detector After the discovery of a Higgs boson, the direct observation of the coupling of this particle to top quarks is of particular importance. In this talk, a review of the latest ATLAS results on the search for the Higgs boson produced in association with top quarks will be presented. Speaker: Marine Kuna (Universita e INFN, Roma I (IT)) • 190 Combination of couplings of the Higgs boson by the ATLAS experiment with Run 1 data A review of the Run 1 combination of production, decay rates and couplings measurements of the Higgs boson using the ATLAS detector will be presented. The datasets used correspond to integrated luminosities of up to 4.7 fb−1 at √s = 7 TeV and 20.3 fb−1 at √s = 8 TeV. Speaker: Cecilia Taccini (Roma Tre Universita Degli Studi (IT)) • 191 Beyond-the-Standard Model Higgs Physics using the ATLAS Experiment The discovery of a Higgs boson with a mass of about 125 GeV has prompted the question of whether or not this particle is part of a larger and more complex Higgs sector than that envisioned in the Standard Model. In this talk, the latest results from the ATLAS experiment on Beyond-the-Standard Model (BSM) Higgs searches are outlined. Searches for additional Higgs bosons are presented and interpreted in well-motivated BSM Higgs frameworks, such as two-Higgs-doublet Models and the Minimal and Next to Minimal Supersymmetric Standard Model. Speaker: Alexander Madsen (Uppsala University (SE)) • 192 A pure resonance dip signal due to the imaginary interference in heavy resonance search We show that a pure resonance dip signal can arise in general due to imaginary interference term in a invariant mass distribution of heavy resonance search. The necessary and sufficient condition in which the pure resonance dip signal arises is described by two parameters$w/R$and$\phi$, where$w$is ratio of decay width to heavy resonance mass,$R$and$\phi$are relative signal strength and phase between the SM and new physics. We show that the pure resonance dip condition can be realized in heavy Higgses decays into$\gamma\gamma, ZZ$and$t{\bar t}$within 2HDM after they are produced via gluon fusion process. In addition, we discuss not only the pure resonance dip signal, several distinctive resonance shapes are also solely determined by$w/R$and$\phi$. Those resonance shapes play important role for interpreting the observed resonance search data with provided invariant mass resolution. Speaker: Yeo Woong Yoon (Konkuk Univ.) • 193 The Holographic Twin Higgs We present the first realization of a "twin Higgs" as a holographic composite Higgs model. Uniquely among composite Higgs models, the Higgs potential is protected by a new SM-singlet elementary "mirror" sector at the sigma model scale f and not by the composite states at$m_{KK}$, naturally allowing for$m_{KK}$beyond the LHC reach. As a result, naturalness in our model cannot be constrained by the LHC, but may be probed by precision Higgs measurements at future lepton colliders, and by direct searches for KK excitations at a 100 TeV collider. Speaker: Michael Geller (Technion) • 194 Probing Natural Colorless Top Partners Theories of physics beyond the Standard Model that address the hierarchy problem generally have partner particles to the top quark that cancel its divergent contributions to the Higgs mass. Following the penetrating, but as yet unfruitful, searches for new colored particles at the LHC, natural extensions of the standard model with color neutral top partners are increasing in appeal. While direct production of these partners can be relatively difficult, because they have sizable couplings to the Higgs boson they can have measurable effects on Higgs production and decay when the particles are not too heavy, or when the theory is natural. We show these variations from standard model Higgs physics for the Twin Higgs, Folded Supersymmetry, and Quirky Little Higgs models. In particular, LHC Higgs physics alone will not be able to strongly disfavor natural realizations of these models. We also discuss additional collider studies that may meaningfully constrain, or discover, these models. Speaker: Christopher Verhaaren (University of Maryland, College Park) • Tools G26 ### G26 #### University of Pittsburgh Pittsburgh, PA 15260 Convener: Dr Neil Christensen (University of Pittsburgh) • 195 Mini-Review: Matrix Element Techniques Speaker: Konstantin Matchev (University of Florida (US)) • 196 Searching for new collider resonances through topological models We propose a systematic way of searching for new physics at colliders that compliments existing strategies. Starting from a given final state topology we survey the possible resonance structures that lead to such a final state. As a case study we examine the *lljj* final state and propose analysis techniques and give sensitivity estimates for the$\sqrt{s}=14\ TeV$and$\mathcal{L}= 300\ fb^{-1}\$ LHC run.
Speaker: Mohammad Abdullah (University of California , Irvine)
• 197
Discovering New Physics with Voronoi Tessellations
Edge detection and inferring distributions from discrete data are both important problems in particle physics, especially in searching for physics beyond the standard model. We demonstrate how methods involving Voronoi tessellations can be used to accomplish both of these tasks.
Speaker: James Gainer (University of Florida (US))
• 198
On the implementation of the UED model in Pythia, CalcHEP and MadGraph
We study analytically and numerically the production cross-sections in the UED model where all SM model fields propagate in one extra compact dimension. We derive analytical formulas for the parton-level cross-sections in the general case of non-degenerate KK masses. We compare numerically three existing mUED implementations: PYTHIA, CalcHEP and MadGraph. We identify and remove some inconsistencies in the mUED implementation in Pythia. We also estimate the size of previously neglected diagrams with level 2 KK partners, as well as diagrams mediated by electroweak KK partners.
Speaker: Ms Dipsikha Debnath (University of Florida)
• 199
Automated Event Plotting with RHADAManTHUS (Recursively Heuristic Analysis, Display, And Manipulation: The Histogram Utility Suite)
RHADAManTHUS is a consumer-level tool for the automated graphical representation and optimization of collider event statistics. A simple, compact, and powerful meta-language syntax facilitates the generation of sophisticated publication-quality plots based upon instructions supplied in a reusable card file. The weighted recombination and over-sampling of distinct or duplicative data channels is handled transparently. All event statistics computable by the companion package AEACuS (as well as arbitrary user-supplied functions thereof) may be leveraged as histogram keys, or as criteria for event selection. Individual histograms may likewise be merged and/or functionally transformed at the bin-by-bin level. Available features include log/linear valuation, variable width binning, left/right bin integration, bin normalization, and bin smoothing.
Speaker: Joel Wesley Walker (Texas A & M University (US))
• 200
Recent improvements on Monte Carlo modelling at ATLAS
The most recent findings on the Monte Carlo simulation of proton-proton collisions at ATLAS are presented. In this, the most recent combined MPI and shower tunes performed using 7 TeV ATLAS data are reported, as well as improved modelling of electroweak processes, and processes containing top using recent MC generators and PDF sets.
Speaker: Rachik Soualah (Universita degli Studi di Udine (IT))
• 201
One-loop Feynman integrals made easy with Package-X
Package-X is a Mathematica package designed to analytically compute dimensionally regulated one-loop Feynman integrals. UV-divergent, IR-divergent and finite parts are all obtained analytically for any combination of external invariants or internal masses. In this talk, Package-X will be showcased with a series of illustrative applications highlighting its ease of use. Technical details are given in [arXiv:1503.01469][1], Package files are available at http://packagex.hepforge.org. [1]: http://arxiv.org/abs/1503.01469 [2]: http://packagex.hepforge.org
Speaker: Hiren Patel (Max Planck Institute)
• Banquet Soldiers and Sailors Hall and Museum

### Soldiers and Sailors Hall and Museum

#### University of Pittsburgh

Pittsburgh, PA 15260
• Wednesday, May 6
• 8:00 AM
Breakfast Alumni Hall 7th Floor

### Alumni Hall 7th Floor

#### University of Pittsburgh

Pittsburgh, PA 15260
• Plenary V Alumni Hall 7th Floor Auditorium

### Alumni Hall 7th Floor Auditorium

#### University of Pittsburgh

Pittsburgh, PA 15260
Convener: Keith Dienes
• 202
Neutrino Physics
Speaker: Mayly Sanchez
• 203
Neutrino and Lepton Theory
Speaker: Silvia Pascoli (University of Durham (GB))
• 204
Symmetries in Cosmology and Large Scale Structure
Speaker: Lam Hui
• 10:30 AM
Coffee Break Alumni Hall 7th Floor

### Alumni Hall 7th Floor

• Plenary VI Alumni Hall 7th Floor Auditorium

### Alumni Hall 7th Floor Auditorium

#### University of Pittsburgh

Pittsburgh, PA 15260
Convener: Xerxes Tata
• 205
Where is SUSY?
Speaker: Howard Baer (University of Oklahoma)
• 206
Physics and Perspectives of the ILC
Speaker: Dr Shigeki Matsumoto (KEK)
• 207
HEP: Future Perspectives
Speaker: James Daniel Wells (University of Michigan (US))