There have been recent excitement regarding certain B-decays both in the charged and neutral current sectors. In the charged sector, the measurement of $R_D$ and $R_{D^*}$ may point to the existence of Physics Beyond the Standard Model, and is thus worth discussing threadbare. Building on our earlier paper (JHEP 1701 (2017) 125), we carry out a comprehensive analysis of these anomalies in as...
In the next-to minimal supersymmetric standard model (NMSSM) an additional singlet-like Higgs boson with small couplings to the standard model (SM) particles is introduced. Although the mass can be well below the discovered 125 GeV Higgs boson its small couplings may make a discovery at the LHC difficult.
We use a novel scanning technique to efficiently scan the whole parameter space and...
A promising way to identify the nature of dark matter (DM) and to measure its
properties and spatial distribution is to search for the gamma rays produced in annihilation or decay of DM particles in the local Universe.
In particular, ground-based Cherenkov gamma-ray telescopes are sensitive to WIMPs of mass above ~100 GeV. The current generation of instruments, such as H.E.S.S., MAGIC and...
Current experimental searches for new physics seem to have cornered the simplest versions of the Minimal Supersymmetric Standard Model (MSSM). Then, we are compelled to consider less constrained scenarios such as the phenomenological MSSM (pMSSM). However, scanning the parameter space of the pMSSM looking for configurations that fulfil all the experimental bounds is known to be a...
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 inclusive searches for supersymmetric squarks of the first two generations, and gluinos in R-parity conserving models that predict dark matter candidates. The searches target final states including jets,...
Effective b->c cbar s operators affect a range of B meson processes, providing a rich phenomenological testing ground for studies of new physics. It is often assumed that such operators will not generate a sizeable BSM contribution, however a comprehensive model independent treatment implies that some observables are sensitive to new physics effects, motivating a phenomenological study of the...
I will present the quartification Grand Unified Theory as a new extension of the supersymmetric trinification model with a local family SU(3)_F symmetry. I will discuss its origin inspired by the breaking of E8 into E6 x SU(3)_F and will briefly address how such a construction may possibly provide a chiral theory. The evolution of the gauge couplings to low energy-scales will be thoroughly...
ANTARES, the deep-underwater Cherenkov neutrino telescope in the Northern hemisphere, has been taking data continuously since 2007. Its primary goal is the search for astrophysical neutrinos in the TeV-PeV range. Thanks to its excellent angular resolution, ANTARES has performed dedicated searches for promising neutrino source candidates and several interesting regions like the Galactic Plane...
The MSSM predicts the existence of additional neutral and charged Higgs
bosons. This presentation will discuss results from recent searches for
neutral Higgs bosons in several leptonic decay channels based on collision
data collected at 13 TeV, and their interpretation within the MSSM.
Searches for the pair-production of colored supersymmetric particles in events without isolated leptons are presented. The results cover different scenarios of gluino and squark production. The interpretation includes models of split supersymmetry that predict long-lived gluinos. The results are based on proton-proton collisions recorded at sqrt(s) = 13 TeV with the CMS detector.
The Belle II experiment is a substantial upgrade of the Belle detector and will operate at the SuperKEKB energy-asymmetric $e^+ e^-$ collider. The accelerator has already successfully completed the first phase of commissioning in 2016 and first electron positron collisions in Belle II are expected for April 2018. The design luminosity of SuperKEKB is $8 \times 10^{35}$ cm$^{-2}$s$^{-1}$ and...
Neutrino telescopes have a wide scientific scope both for particle physics and astroparticles. The next-generation undersea detector, KM3NeT, is currently under construction on two sites in the Mediterranean: ORCA, a dense detector located close to the French coast –near the location of its predecessor, ANTARES–, and ARCA, a sparse detector located close to the Italian coast. ORCA, with an...
Many supersymmetric scenarios feature final states with non-standard final state objects. The production of massive sparticles can lead to the production of boosted top quarks or vector bosons, high-pt b-jets. At the same time, transitions between nearly mass-degenerate sparticles can challenge the standard reconstruction because of the presence of very soft leptons or jets. The talk will...
The MSSM predicts the existence of additional neutral and charged Higgs
bosons. This presentation will discuss results from recent searches for
charged Higgs bosons in several decay channels based on collision data
collected at 13 TeV, and their interpretation within the MSSM.
We use the IR fixed point predictions for gauge couplings and the top Yukawa coupling in the MSSM extended with vectorlike families to infer the scale of vectorlike matter and superpartners. We quote results for several extensions of the MSSM and present results in detail for the MSSM extended with one complete vectorlike family. We find that for a unified gauge coupling α_G>0.3 vectorlike...
We discuss QCD uncertainties in the modelling of the gamma-ray energy spectra from Dark-Matter (DM) annihilation in the galaxy center and beyond.
Dark Matter particles, being neutral, cannot couple directly to photons.
Photons are instead produced as the result of the fragmentation and decay of the particles the DM annihilates into.
In phenomenological studies the photons energy spectra are...
Precision measurements of CP violating observables in b hadron decays
are powerful probes to search for physics effects beyond the Standard
Model. The most recent results on CP violation in the decay, mixing and
interference of b hadrons obtained by the LHCb Collaboration will be
presented, with particular focus on results obtained exploiting the data
collected during the Run 2 of LHC.
The next-to-minimal supersymmetric Standard Model (NMSSM) contains two additional singlet-like Higgs bosons, one scalar and one pseudoscalar, besides the three neutral ones of the MSSM. A signature of either of these new Higgs bosons at the Large Hadron Collider (LHC) can prove crucial for establishing the non-minimal nature of supersymmetry. However, their masses are essentially free...
Although the standard model of particle physics is successful in describing physics as we know it, it is known to be incomplete. Many models have been developed to extend the standard model, none of which have been experimentally verified. One of the main hurdles in this effort is the dimensionality of these models, yielding problems in analysing, visualising and communicating results. Because...
Searches for the pair-production of colored supersymmetric particles in events with one or more isolated leptons are presented. The results cover different scenarios of gluino and squark production. The leptons can originate from the decays of vector bosons or supersymmetric lepton partners produced in the decay chain. The results are based on proton-proton collisions recorded at sqrt(s) = 13...
Rare decays are powerful probes for Physics beyond the Standard Model
(SM), as new particles can have a large impact on physics observables.
Recent results on lepton universality tests and measurements of
branching fractions and angular distributions of rare b->sll decays have
shown tensions with the SM predictions. The LHCb experiment is ideally
suited for the study of the these flavour...
We discuss a neutrinophilic two Higgs doublet model realized by a hidden local $U(1)$ symmetry, where active neutrinos are Dirac type, and a fermionic DM candidate is naturally induced as a result of remnant symmetry. In addition, a physical Goldstone boson is arisen as a consequence of two types of gauge singlet bosons and contributes to the DM phenomenologies as well as additional neutral...
The precise study of the Higgs boson properties -- in particular its mass and couplings -- is of paramount importance for the study of BSM models with enlarged Higgs sectors.
In particular, when investigating the high-scale behaviour of these models, the scalar quartic couplings must be extracted from the physical spectrum. I will show that it is then crucial to include all known higher-order...
Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the third generation quarks with masses not too far from those of their Standard Model counterparts. The phenomenology ranges from final states of top or bottom quark pairs and two dark matter candidates, to more complex scenarios involving non-prompt sparticle decays or R-parity violating signatures. This...
In natural GUT, various problems in SUSY GUT, including the doublet-triplet splitting problem, can be solved with a natural assumption in which all interactions (incl. higher dimensional interactions) which are allowed by the symmetry are intoduced with O(1) coefficients. In the models, the Fayet-Iliopoulos (FI) term plays an important role. The FI term can also play an critical role in...
We propose a new dynamical relaxation mechanism for the little hierarchy problem, based on a singlet extension of the minimal supersymmetric standard model (MSSM).
In this scenario, a small soft mass parameter of an MSSM singlet is responsible for the electroweak symmetry breaking and the non-zero Higgs vacuum expectation value, whereas the effect of a large soft mass parameter of the Higgs...
In supersymmetric models with scalar sequestering, superconformal strong dynamics in the hidden sector suppresses the low-energy couplings of mass dimension two, compared to the squares of the dimension one parameters. Taking into account restrictions on the anomalous dimensions in superconformal theories, I point out that the interplay between the hidden and visible sector renormalizations...
The accumulation of 36fb-1 of data at 13 TeV has been a unique window for supersymmetry searches at the LHC, allowing the CMS collaboration to search for specific supersymmetric particles. This talk covers searches of supersymmetric particles of 3rd generation squarks, which might be the only sparticles produced at the LHC, other sparticles being too heavy. It will highlight "compressed...
We present a four-dimensional model where the Higgs mass is protected from the quadratic one-loop top quark corrections by scalar particles that do not carry standard model (SM) color charges. They can even be complete SM singlets. The cancellation of the quadratic divergence is ensured by a Z_3 symmetry that relates the SM top sector and two hidden top sectors, each charged under its own...
I will review the calculation of the SUSY-QCD two-loop corrections to the strange and bottom Yukawa couplings in the MSSM. They include the resummation of the dominant corrections for large values of tan(beta), as well as the subleading terms induced by the trilinear Higgs couplings A_b,s. The phenomenological impact of the calculation will also be discussed.
This talk introduces a novel solution to astrophysical small-scale problems, (i.e. core/cusp and too-big-to-fail) by invoking a certain class of dark matter self-annihilating processes. Such processes lead to the formation of dark matter cores at late times by considerably reducing the inner mass density of dwarf-sized halos. An important aspect of this new solution is that the...
Flavor symmetries à la Froggatt-Nielsen (FN) provide a compelling way to explain the hierarchies of fermionic masses and mixing angles in the Yukawa sector. In Supersymmetric (SUSY) extensions of the Standard Model where the mediation of SUSY breaking occurs at scales larger than the breaking of flavor, this symmetry must be respected not only by the Yukawas of the superpotential, but by the...
If Dark Matter (DM) interacts with nucleons and/or electrons it can be trapped in celestial bodies. For a Neutron Star (NS), DM accumulating in the center could form a core which could further gravitationally collapse into a black hole. The requirement that such collapses do not occur gives constraints on the DM mass and interaction strength. Such phenomenon crucially depends on the amount of...
Searches for supersymmetry at the LHC have pushed the mass limits for strongly-produced sparticles to the TeV level. At this scale, even heavy decay products such as vector or Higgs bosons can be produced at high transverse momenta and make the reconstruction and identification of boosted objects to an essential tool for current and future searches for supersymmetry. The talk summaries the use...
Supersymmetric theories supplemented by an underlying flavor-symmetry provide a rich playground formodel building aimed at explaining the flavor structure of the Standard Model. In the case where supersymmetry breaking is mediated by gravity, the soft-breaking Lagrangian typically exhibits large tree-level flavor violating effects, even if it stems from an ultraviolet flavor-conserving origin....
We calculate quark and gluon jet fraction in multi-jet final states at the LHC, which is based on perturbative QCD at next-to-double logarithmic accuracy. We find a measurable scaling pattern of the fraction. This is related to a performance of new physics searches using quark-gluon jet discrimination in multi-jet final states, and would be useful for more understanding of QCD and tuning of...
In scenarios of the Minimal Supersymmetric Standard Model where the gravitino is the LSP and the Stop is the NLSP, the Stop could have a long life-time, which makes it a quasi-stable particle that requires special strategies for its search at hadron colliders. We calculate the lifetime for the stop decay in different regions of parameter space where the different N-body modes are open,...
Neutron stars (NSs) are promising indirect probes for dark matter (DM), dark kinetic heating of NSs is within the reach of forthcoming infrared telescopes and only depends on the amount of accumulated DM. Inelastic DM is suppressed at tree level in direct detection experiments. Assuming that kinetic heating of NSs is only due to DM scattering and using an effective operator approach on...
The decay K+→π+νν, with a very precisely predicted branching ratio of less than 10-10, is one of the best candidates to reveal indirect effects of new physics at the highest mass scales. The NA62 experiment at CERN SPS is designed to measure the branching ratio of the K+→π+νν with a decay-in-flight technique, novel for this channel. NA62 took data in 2016, 2017 and another year run is...
In the near future, fundamental interactions at high-energy scales may be most efficiently studied via precision measurements at low energies. In this talk I will discuss the possible impact of the DUNE neutrino experiment on constraining the Standard Model Effective Field Theory. The unprecedented neutrino flux offers an opportunity to greatly improve the current limits via precision...
We present the renormalization of the munuSSM and its application to higher-order corrections in the scalar sector. We show the phenomenological relevance of these higher-order calculations and compare with the corresponding results in the NMSSM.
XENON1T is a direct dark matter search experiment, currently taking data at the Laboratori Nazionali del Gran Sasso (LNGS), Italy, and the first multi-ton scale detector of this kind. The experiment is based on a xenon dual-phase (liquid-gas) time projection chamber with ~2000 kg of target mass (out of 3200 kg total xenon mass), exploiting both scintillation and ionization signals to...
Theories beyond the Standard Model predict Higgs boson decays that do not
exist in the Standard Model, such as decays into two light bosons (a). This
talk presents recent results based on pp collision data collected at 13 TeV.
DarkSide uses a dual-phase Liquid Argon Time Projection Chamber to search for WIMP dark matter. The talk will present the latest result on the search for low mass ($M_{WIMP} <20GeV/c^2$ ) and high mass ($M_{WIMP}>100GeV/c^2$) WIMPs from the current experiment, DarkSide-50, running since mid 2015 a 50-kg-active-mass TPC, filled with argon from an underground source. The next stage of the...
We consider an extension of the Standard Model by right-handed neutrinos and we argue that, under plausible assumptions, a neutrino mass of O(0.1)eV is naturally generated by the breaking of the lepton number at the Planck scale, possibly by gravitational effects, without the necessity of introducing new mass scales in the model. Some implications of this framework are also briefly discussed.
We study the Next-to-Minimal Supersymmetric Standard Model (NMSSM)
with non-universal gaugino masses at the unification scale.
A singlet superfield is added to the minimal supersymmetric (SUSY)
extension of the Standard Model.
Its vacuum expectation value gives a SUSY-scale mass term for higgsinos.
The presence of the singlet field makes the Higgs potential complicated
and it is non-trivial...
Theories beyond the Standard Model predict Higgs boson decays at a much
enhanced rate compared to the Standard Model, e.g. for decays to Z+photon or a
meson and a photon. This talk presents recent results based pp collision data
collected at 13 TeV.
Although deep learning might appear as a magic black box one only needs to throw data at to receive a solution, the practical reality is always different and often difficult. This talk shall guide through an example for the process of constructing an AI for predicting a physical quantity, namely the pMSSM-19 NLO electroweakino production cross-section at the LHC for 13 TeV. Naively, one could...
For more than 20 years the DAMA/LIBRA collaboration has reported a positive annual modulation in the low-energy detection rate of their NaI(Tl) detectors with very high C.L., that has been recently updated to 12.9$\sigma$. The interpretation of this result as a WIMP signal in standard models is, however, in strong tension with the null results of other experiments. Therefore there is an urge...
Assume that dark matter couples mostly to the top-quark. This hypothesis is well motivated in models with scalar mediators, where flavor-hierarchical couplings to quarks prevent large flavor-changing neutral currents. In this talk, we discuss searches for dark matter produced in association with top-quarks at the LHC. We propose single-top-associated production as a new search channel for dark...
Neutrino oscillation phenomenology requires an explanation for the origin of neutrino masses. Low-scale models, generally motivated by symmetry arguments, have been shown to be testeable at current and future colliders.
We consider the possibility of distinguishing the Pseudo-Dirac or Majorana nature of new heavy neutrinos at Electron-Positron colliders. We show that lepton number violating...
Many supersymmetry models feature gauginos and sleptons with masses less than a few hundred GeV. These can give rise to direct pair production rates at the LHC that can be observed in the data sample recorded by the ATLAS detector. The talk presents recent ATLAS results from searches for slepton pair production.
Phenomenological studies of SUSY models typically imply the sampling of multidimensional parameter spaces. Each parameter point needs to be checked against the available theoretical and experimental limits from indirect and direct SUSY searches. The constraints from electroweakino searches are particularly challenging due to the computational resources needed to calculate their production...
The Belle II experiment is a substantial upgrade of the Belle detector and will operate at the SuperKEKB energy-asymmetric $e^+ e^-$ collider. The accelerator has already successfully completed the first phase of commissioning in 2016 and first electron positron collisions in Belle II are expected for April 2018. The design luminosity of SuperKEKB is $8 \times 10^{35}$ cm$^{-2}$s$^{-1}$...
The Standard Model of particle physics have been extremely successful so far, but there are still many unanswered questions like the origin of neutrino mass, nature of dark matter, the source of quark and lepton flavor mixing and their possible correlation, the theory of grand unification of all SM interactions. In this talk I will focus on some interesting models that attempt to answer these...
A systematic procedure to obtain the 1-loop low-energy effective Lagrangian resulting from integrating out the heavy fields of a given ultraviolet theory is presented in this talk. It is shown that the matching coefficients are determined entirely by the hard region of the functional determinant involving the heavy fields. This represents an important simplification with respect the...
Searches for the production of supersymmetric partners of electroweak gauge and Higgs bosons are presented. The focus of the talk will be on SUSY models with compressed mass spectra, as they are expected if the lightest of these states are dominantly partners of the Higgs bosons. The talk will also cover searches for the direct production of supersymmetric partners of electrons and muons. The...
We make use of the recently released threshold-resummation improved PDF sets to consistently calculate theoretical predictions for slepton pair production and electroweakinos associated production at NLO+NLL accuracy. The updated cross sections have been carried out for the ongoing Run-II of the LHC and for the relevant processes that are considered in experimental searches. We study the cases...
Precision measurements of multi-boson production is a validation of the Standard Model. These multi-boson processes are a background to Higgs measurements and searches for Beyond the Standard Model physics. In this talk, we present the recent measurements of multiboson final states performed in CMS, involving W, Z and photon combinations. Inclusive and differential cross sections are compared...
The high-intensity setup, trigger system flexibility, and detector
performance -- high-frequency tracking of beam particles, redundant
PID, ultra-high-efficiency photon vetoes ― make NA62 particularly
suitable for searching new-physics effect from different
scenarios. Results from a search for invisible dark photons produced
from pi0 decays are given. Fixed target experiments are...
Charginos and neutralinos are typically the lightest new particles predicted by a wide range of supersymmetry models, and the lightest neutralino is a well motivated and studied candidate for dark matter in models with R-parity conservation. The talk presents recent results from searches for pair produced charginos and neutralinos in final states with leptons and missing transverse momentum.
Sub-MeV dark matter remains unconstrained by direct detection, and there are several well-motivated candidates in this mass range. Electron recoil experiments have been proposed as a technique to detect such a light particle, but little is known about the extent of cosmological restrictions on a generic light species coupled to electrons. We study cosmological constraints on a light dark...
In this talk, the status of the predictions for the partial decay widths of different more or less exotic Higgs bosons, i.e. SM-like Higgs bosons in extensions of the Standard Model as well as additional neutral or charged Higgs bosons, will be discussed. I will comment on different possible parameter definitions and the resulting consequences. In particular, I will report on recent results...
The production of massive vector boson pairs is a key process for the understanding of the non-abelian gauge structure of the standard model and for the comprehension of the electroweak symmetry breaking mechanism. The study of the production of vector boson pairs with the presence of two jets in the event allows to measure the electroweak production of vector bosons in association with jets,...
Searches for the supersymmetric particles in events with one or more hadronically decaying tau leptons are presented. The results focus on the stau pair production, and in addition address scenarios with electroweakly produced SUSY particles leading to final states with multiple tau leptons. The results are based on proton-proton collisions recorded at sqrt(s) = 13 TeV with the CMS detector.
VERITAS is a ground-based gamma-ray observatory consisting of an array of four atmospheric Cherenkov telescopes located in southern Arizona, USA. VERITAS carries out an extensive observation program of the gamma-ray sky at energies above 0.1 TeV (VHE). The majority of the sources detected by VERITAS are active galactic nuclei, with gamma-ray emission originating in their relativistic jets. TeV...
I will review recent progress in the calculation of the Higgs masses in various MSSM scenarios with heavy superparticles. I will describe advances in the calculation of the matching conditions for the couplings of the EFT valid below the SUSY scale, in the combination of the resummed logarithmic corrections obtained in the EFT approach with the existing fixed-order calculations of the Higgs...
Semi-annihilation describes non-decay processes with an odd number of external dark sector states. The canonical example is an initial state of two dark particles and a final state of one dark plus one or more standard model particles. It is a generic feature of dark matter whenever the symmetry group enforcing stability is not a discrete $Z_2$. Semi-annihilation changes the expected signals...
Measurements of Higgs boson properties and cross sections measured in Higgs
boson decays to two photons, two Z bosons, and two W bosons based on pp
collision data collected at 13 TeV are presented. In addition, results from
the combination of different decay channels are shown.
Fine-tuning arguments suggest the mass of the supersymmetric partner of the Higgs boson, the higgsino, is not too far from the weak scale. The search for higgsinos represents an experimental challenge due to the near mass-degeneracy resulting in soft decay products, and the low production cross section. This talk presents recent ATLAS results of analyses explicitly targeting the higgsino with...
In the next decade, accelerator upgrades are expected in various facilities, making it feasible to have continuous muons beams with an intensity of $10^9$ or even $10^{10}$ muons per second. These progresses would open new prospects in the search for the Lepton Flavor Violating decay $\mu \to e \gamma$. We discuss the potential sensitivity to this decay for experiments exploiting continuous...
In models with Higgs sectors larger than 2 Higgs doublets, as for example found in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), decays of heavy Higgs bosons into pairs of lighter Higgs bosons or a Z boson and a light Higgs (so-called Higgs cascade decays) can have large branching ratios. The presence of the 125 GeV SM-like mode suppresses the couplings of additional heavy Higgs...
We revisit charged lepton flavor violating (CLFV) scattering processes $\ell_{i} N \to \tau X \, (\ell_{i} \ni e, \mu)$ mediated by Higgs. (Although in this talk we focus on Higgs CLFV, our results hold for other CLFV mediators which couple with gluon and/or heavy quarks.) We point out that a new subprocess $\ell_{i} g \to \tau g$ via the effective interactions of Higgs and gluon gives the...
If dark matter annihilation is velocity dependent, then the J-factors associated with any astrophysical target depend on the full dark matter phase space distribution. We calculate these velocity-dependent J-factors for a variety of targets and a variety of choices for the velocity-dependence of DM annihilation. Significantly, we find that the choice of velocity-dependence affects the...
Measurements and searches of Higgs boson decays to two third- or two second-
generation quarks or leptons are presented using pp collision data
collected at 13 TeV.
The discovery of the Higgs boson with a mass of 125.09 GeV significantly constrains the allowed parameter space of the many SUSY models that predict the mass of the lightest Higgs boson to be of the order of the Z mass at tree-level. In these models, among which the MSSM is probably the most studied, large loop corrections are necessary to obtain a light Higgs boson mass compatible with the...
We investigate the muon anomalous magnetic moment, the μ→eγ branching ratio and the μ→e conversion rate in the nuclei from the point of view of the planned μ→e conversion experiments.
In the MSSM these processes are strongly correlated through tanβ enhanced contributions. We demonstrate how in the Minimal R-symmetric Supersymmetric Standard Model the μ→eγ branching ratio and the μ→e...
I will describe a version of the dimensional regularization of a classically scale invariant theory, motivated by the requirement to preserve scale invariance at the level of loop corrections. The theory is embedded in a nonrenormalizable Lagrangian, where both the dimensionful regulator \mu and suppression scale of higher-dimensional interactions are interpreted as a vev of a new dynamical...
Events with isolated photons in the final state can be used in multiple ways to search for supersymmetry. Depending on the composition of the lightest neutralino state, decays to a photon and the gravitino can be a dominant signature for models with gauge-mediated supersymmetry breaking. Photons are also a tool for the identification of Higgs bosons in the decay chains of supersymmetric...
In some models for WIMP dark matter, radiative corrections dominate over the LO contributions in the computation of annihilation cross sections relevant for indirect detection. These corrections need to be resummed to all orders in perturbation theory for theoretical predictions to be sensible.
In this talk I will employ -and briefly review- resummation methods that are traditionally used in...
The non-observation of superpartners at the LHC coupled with a measured mass of the Higgs boson of $\sim125$ GeV, which points to relatively heavy spectra, has renewed the interest in the study of SUSY scenarios where most/all superpartners lie significantly above the EW scale. In this context an Effective Field Theory (EFT) approach to the Higgs mass computation is needed, in order to...
LHCb has collected the world's largest sample of charmed hadrons. This sample is used to measure $D^0- \bar D^0$ mixing and to search for direct and indirect CP violation. New measurements from several decay modes are presented.
Based on arXiv:1801.08849, this talk will look at how Higgs alignment can be realised naturally in a low energy type-II Higgs doublet model, originating from Dirac gaugino models with extended supersymmetry at higher energies. It will be discussed how alignment, predicted at tree-level at the scale of the extended supersymmetry, is maintained in the low energy effective theory even after...
Gauge coupling unification and the stability of the Higgs vacuum are among two of the cherished features of low-energy supersymmetric models. Though low-energy supersymmetry is still viable, it could be that supersymmetry is manifest only at very high energies. If this is the case, it is a legitimate question whether any or all of the problems with cures normally attributed to weak-scale...
Di-lepton production at the LHC and Direct Detection (DD) limits put strong constraints on simplified DM models where the DM particle is a fermion, coupled to the SM through an extra U(1)' gauge boson, Z'. The first problem can be avoided by demanding vanishing Y'-charges for leptons (leptophobia). Then, the requirement of anomaly cancellation imposes strong and non-trivial constraints on the...
SUSY continues to elude direct searches at Run 2 of the LHC. Hence, indirect probes like electroweak precision observables are relevant to explore the parameter space of a model. The mass of W boson is such an observable where the LHC experiments are on their way improve on the uncertainties of the experimental result. The prediction for $M_W$ has been studied in depth in the MSSM and NMSSM....
We study the electroweak phenomenology of Higgs Inflation within the Next-to-minimal Supersymmetric Standard Model (NMSSM). The model has a superconformal symmetry at high scales which is broken by the non-minimal coupling to supergravity responsible for early universe inflation. At low energies, however, the model differs from the usual NMSSM. With an emphasis on the Higgs and Neutralino...
We report on multiple recent searches for supersymmetric, LFV/LNV, and other BSM effects with data collected by the BaBar experiment at the PEP-II e+e- collider. Using the entire BaBar dataset, we report the results of searches for: 1) the rare decay D0 -> Kpie+e-, and generic LFV/LNV D -> hh'll' decays; 2) Y(3S) -> e+mu- decays; and 3) beyond-SM T- and CP-violating effects in neutral B...
In the MSSM, light scalar top quarks are well motivated and
often contribute significantly to the neutralino dark matter
relic density. We present a new precision calculation of
stop annihilation into heavy quarks at next-to-leading order
of SUSY-QCD and with Coulomb resummation effects and discuss
the size and uncertainty of these corrections with respect
to the experimental measurement of...
The axion solution to the strong CP problem also provides a natural
dark matter candidate. If the PQ symmetry has ever been restored after
inflation, topological defects of the axion field would have formed and
produced relic axions, whose abundance is in principle calculable. Using
numerical simulations I will present a detailed study of the evolution of
axion strings and the resulting...
I present the most general bounds we can make on operators in hidden CFTs, which are weakly coupled to the SM via a heavy mediator. The conformal symmetry dictates an unusual phase space for the generated particles, which led H. Georgi to coin the term 'Unparticles'. Using the unparticle formalism, we constrain a large class of hidden valley theories without the need to specify their particle...
We study emission processes of gravitational waves (GWs) from string axions with various masses. First, we clarify the conditions of the onset of violent parametric amplification of inhomogeneous axions. Then, we investigate the fate of the instability with lattice simulations. We analyze GW production processes due to the axion dynamics and find the pre-oscillon formation stage is important...
Measurements of the inclusive and differential cross-sections of top-quark
production in proton-proton collisions at centre-of-mass energy of 13 TeV with
the ATLAS detector at the Large Hadron Collider are presented. Single top-quark and top-quark pair final states as well as top-quark production in association with vector bosons are considered. The measurements reach high precision and are...
Is supersymmetry fading? Or is there still enough experimental evidence to support our faith in it? In search of a quantitative answer, I review the latest GAMBIT results for the CMSSM, NUHM1 and 2, MSSM7 and MSSM9.
The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, this gives the unique opportunity to probe the properties of bare quarks. This talk will focus on a few recent precision measurements of top quark properties in top-quark pair and single top-quark events by the ATLAS Collaboration. Measurements of the top quark mass and searches...
I consider the keV scale axino dark matter in the supersymmetric Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) axion model. The axino dark matter is dominantly produced from freeze-in processes, and it decays into a monochromatic photon that can be measured by X-ray observations. However, keV scale dark matter normally has a tension with the constraints from Ly-alpha forest data. In this talk, I...
The first-order electroweak phase transition in the early universe could occur in multiple steps leading to specific multi-peaked signatures in the primordial gravitational wave (GW) spectrum. In this talk we argue that these signatures are generic phenomena in multi-scalar extensions of the Standard Model. In a simple example of such an extension, we study the emergence of reoccurring and...
We have explored a minimal supersymmetric Standard Model scenario extended by one pair of gauge singlets per generation, where light neutrino masses and mixing are generated via inverse seesaw mechanism. In such a scenario, a right-handed sneutrino can be the lightest supersymmetric particle and a cold Dark Matter (DM) candidate. We have studied the constraints on such a scenario arising from...
Little Higgs models are a class of models to solve the hierarchy
problem by protecting the Higgs mass at one loop with the help
of global symmetries.
We were studying the constraints by recasting the most prominent SUSY signatures like jets (and leptons) plus missing transverse energy.
In order to relax bounds from direct detection searches for dark matter we also consider the collider...
Many Standard Model extensions that address the hierarchy problem contain Dirac-fermion partners of the top quark, which are typically expected around the TeV scale. Searches for these vector-like quarks mostly focus on their decay into electroweak gauge bosons or Higgs plus a standard model quark. In this talk, backed by models of composite Higgs, we propose a set of simplified scenarios that...
In this talk, we consider the standard model extension with a dark sector with the $U(1)_X$ Abelian gauge symmetry, which is spontaneously broken by dark Higgs mechanism. We discuss patterns of the electroweak phase transition and detectability of gravitational waves (GWs) when strongly first order phase transition occurs. We find the collider bounds exclude a part of parameter space that...
We present a study of searching for massive long-lived particles at the MoEDAL detector. MoEDAL is sensitive to highly ionizing avatar such as magnetic monopoles or massive (meta-)stable charged particles and we focus on the latter in this talk. In the ATLAS and CMS analyses for long-lived particles, some conditions are usually required for triggering or reducing the cosmic ray background,...
The mechanism of “spontaneous leptogenesis” — in which the matter-antimatter asymmetry is generated via motion of a scalar field coupled to the electroweak gauge bosons — provides an interesting alternative to more traditional thermal leptogenesis models. While an axion-like field is a natural candidate for these models, the observed asymmetry requires an axion mass so large it decays shortly...
The top quark mass is a fundamental parameter of the Standard Model, entering in the precision tests even before the Higgs discovery and playing a crucial role in any assumption on the stability of the electroweak vacuum. Therefore, determining it with the highest precision and having under control all sources of errors will be of paramount importance. I will investigate the uncertainties in...
Cosmic strings are generic cosmological predictions of many extensions of the Standard Model
of particle physics, such as a U(1)′ symmetry breaking phase transition in the early universe.
Unlike other topological defects, cosmic strings can reach a scaling
regime that maintains a small fixed fraction of the total energy density of the universe from a
very early epoch...
Vector like quarks appear in many theories beyond the Standard Model as a way to cancel the mass divergence for the Higgs boson. The current status of the ATLAS searches for the production of vector like quarks will be reviewed for proton-proton collisions at 13 TeV. This presentation will address the analysis techniques, in particular the selection criteria, the background modeling and the...
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 inclusive searches for supersymmetric squarks of the first two generations, and gluinos in less conventional scenarios including R-parity violating models that typically lead to high-multiplicity final...
We investigate the phenomenology of fermion dark matter as an admixture of weak singlet and triplet Majorana fields. Our model can be considered as a generalization of the wino-bino scenario in supersymmetry. The dark sector interacts with the Higgs boson through a pseudo-scalar portal, thus mitigating bounds from direct detection experiments. The observed dark matter abundance is obtained...
We present the measurements of production of the standard model Higgs boson in association with a pair of top quarks. Several Higgs decays are considered and combined together. This search is performed on the full 13-TeV dataset of proton-proton collisions collected by the CMS experiment at the LHC in 2016.
For a realistic scenario of inflationary primordial black holes (PBHs), a highly blue-tilted power spectrum of primordial perturbations is required. In the axion-like curvaton model, which is base on the supersymmetric axion model, such a spectrum is achieved. I will show that PBHs formed in this model can explain the massive black holes implied by the LIGO gravitational wave (GW) events....
We present results of searches for massive vector-like top and bottom quark partners using proton-proton collision data collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV. Single and pair production of vector-like quarks are studied, with decays into a variety of final states, containing top and bottom quarks, electroweak gauge and Higgs bosons. We search...
Searches for R-parity conserving supersymmetry have set stringent limits on sparticle masses. In R-parity violating (RPV) models the characteristic missing transverse momentum signature is absent and these constraints do not apply. Specific searches are designed to detect production and decay of supersymmetric particles via RPV couplings. Results are presented based on data recorded by the CMS...
We construct a self-interacting dark matter model that could simultaneously explain the observed muon anomalous magnetic moment. It is based on a gauged U$(1)_{L_{\mu} - L_{\tau}}$ extension of the standard model, where we introduce a pair of vector-like fermions as the dark matter candidate and a new Higgs boson to break the symmetry at the 10 MeV scale. The new gauge boson has sizable...
The search for the production of the Higgs Boson with a pair of top-anti-top
quarks is both very important and very challenging. This talks presents the
analyses using Higgs boson decays to bbbar pairs, to two Z bosons, to other
multi-lepton final states, and to a pair of photons, using pp collision data
collected at 13 TeV, as well as their combined results.
We review recent progress in the prediction of SUSY Higgs boson masses, focusing on the MSSM and its extensions. The corrections are being included into the public code FeynHiggs. Numerical examples are presented, showing the improved higher-order calculations.
We present an overview of searches for new physics with top and bottom quarks in the final state, using proton-proton collision data collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV. The results cover non-SUSY based extensions of the SM, including heavy gauge bosons, 3rd generation leptoquarks, or excited third generation quarks. Decay channels to...
From strongly produced initial states, SUSY phenomenology offers a rich array of observable signatures. Several supersymmetric models predict massive long-lived supersymmetric particles that may be detected through abnormal specific energy loss, appearing or disappearing tracks, displaced vertices, long time-of-flight or late calorimetric energy deposits. This talk summarises recent ATLAS...
I discuss the production of bileptons at LHC, as predicted in the
so-called 3-3-1 model, yielding final states with two same-sign lepton pairs.
I will show that this signal can be easily separated from the SM backgrounds
and investigate the comparison between scalar (Higgs-like) and vector bileptons, as they are both present in the 3-3-1 scenario.
Today’s standard way to calculate the thermal relic abundance of dark matter via chemical decoupling relies on the assumption that particles remain in kinetic equilibrium throughout the freeze-out process. However, is this assumption always justified?
The talk aims to address this question and discuss the consequences of more accurate treatments. Two methods are presented: One that combines...
Di-Higgs final states can arise through non-resonant production of two Higgs
bosons and through potential heavy states decaying to two Higgs boson. This
talk presents searches in several Higgs boson decay channels using 36 fb-1 of
pp collision data recorded at 13 TeV.
We compare models with a non-universal
gaugino and/or sfermion sector in different grand unification scenarios,
namely SO(10), SU(5), flipped SU(5) and Pati-Salam unification. We explore the different
constraints arising from LHC supersymmetry searches and dark
matter experiments. We also investigate whether the models can predict a
significant SUSY contribution to the muon g-2. We find that...
The measurement of the triple Higgs coupling is a key benchmark for the LHC and future colliders. It directly probes the Higgs potential and its fundamental properties in connection to new physics beyond the Standard Model. We show how the invariant mass distribution of the Higgs pair offers a systematic way to extract the Higgs self-coupling, focusing on the leading channel pp → hh + X → b ̄b...
Motivated by the possibility of enhancing dark matter (DM) self-scattering cross-section σ self , we have revisited the issue of DM annihilation through a Breit-Wigner resonance. In this case thermally averaged annihilation cross-section has strong temperature dependence, whereas elastic scattering of DM on the thermal bath particles is suppressed. This leads to the early kinetic decoupling of...
Several theories beyond the Standard Model predict the existence of new heavy particles decaying into pairs of gauge bosons. In this presentation the latest ATLAS results on searches for resonances decaying into pairs of W bosons, Z bosons or photons focusing on fully leptonic decay channels, based on 36 fb-1 of pp collision data collected at 13 TeV will be discussed.
We propose that natural TeV-scale new physics (NP) with $O(1)$ couplings to the standard model (SM) quarks may lead to a universal enhancement of the Yukawa couplings of all the light quarks, perhaps to a size comparable to that of the SM b-quark Yukawa coupling, i.e., $y_q ∼ O(y_b^{SM})$ for $q = u, d, c, s$. I will discuss this scenario in an effective field theory (EFT) extension of the SM,...
We implement inflation in realistic supersymmetric and non-supersymmetric extensions of the Standard Model. We compare and contrast a number of predictions related to primordial gravity waves, dark matter and proton decay.
Dark matter axions and other highly degenerate bosonic fluids are commonly described by classical field equations. As our recent work, we evaluated the duration of classicality of a homogeneous condensate with attractive contact interactions. In their classical descriptions, such condensate persists forever. Taking into account the quantum description, however, parametric resonance causes...
Many theories beyond the standard model predict new phenomena which decay to leptons and/or jets. Searches for new physics models with these signatures are performed using the ATLAS experiment at the LHC. The results reported here use the pp collision data sample collected by the ATLAS detector at the LHC with a centre-of-mass energy of 13 TeV.
A massive particle charged under the electroweak gauge symmetry, such as a Higgsino and Wino, is one of the most promising candidate of the dark matter and called "Minimal dark matter." Such electroweakly interacting particle will affect the standard model processes thorough quantum effects. In this talk, I will discuss search strategies for such a dark matter with precision measurements of...
Models with extended Higgs sector predict that the diagonal Higgs couplings to fermions could deviate from the SM predictions, while non-diagonal flavor-violating Higgs couplings could appear too. We describe these possibilities within the context of multi-Higgs doublet models that employ the Froggart-Nielsen mechanism to generate the Yukawa hierarchies. The mixing of the Higgs doublets...
We present the result of the search for vector-like leptons in multilepton final states using proton-proton collision data collected with the CMS detector at 13 TeV. Events are primarily categorized into either two light leptons (electron or muon) plus a hadronic tau or three and more light leptons. The scalar sum of transverse momenta of leptons and the missing transverse energy are used to...
We perform a search of Dark Matter (DM) subhalo candidates among unassociated catalogued sources present in the most recent Fermi-LAT point-source catalogs (3FGL, 2FHL and 3FHL). These LCDM-predicted DM subhalos are promising candidates for gamma-ray emission from WIMP annihilation in the LAT energy band. Several selection criteria are applied, based on the expected properties of the...
We examine the phenomenology of the production, at the 13 TeV Large Hadron
Collider (LHC), of a heavy resonance $X$, which decays via other new on-shell particles $n$ into multi- (i.e.\ three or more) photon final states. In the limit that $n$ has a much smaller mass than $X$, the multi-photon final state may dominantly appear as a two-photon final state because the $\gamma$s from the $n$...
The freeze-out of massless particles is investigated. The effects due to
quantum statistics, Fermi-Dirac or Bose-Einstein, of all particles
relevant for the process are analyzed. Solutions of appropriate Boltzmann
equation are compared with those obtained using some popular approximate
methods. As an application of general results the relic density
of dark radiation in Weinberg's Higgs...
We calculate all NMSSM Higgs-boson decays to SM particles at the full one-loop level. Special attention is paid to treat the MSSM part exactly as in the pure MSSM calculation. In this way any deviations can be attributed directly to the extended Higgs (and neutralino) structure in the NMSSM. We compare our results with several approximations used in the literature and emphasize the numerical...
It is one of the major issues to realize a vacuum which breaks supersymmetry (SUSY) and R-symmetry, in a supersymmetric model. We study the model, where the same sector breaks the gauge symmetry and SUSY. In general, the SUSY breaking model without gauge symmetry has a flat direction at the minimum of F-term scalar potential. When we introduce U(1) gauge symmetry to such a SUSY breaking model,...
Natural SUSY models have Higgsinos as the lightest supersymmetric
particles with masses of at most a few hundred GeV. Assuming
that the gauginos are significantly heavier this implies that the
relic dark matter density is significan below the observed values.
At the same time neutrino masses need to be explaine. We propse
thus a model with light right-handed (s)neutrinos where the...
Dark matter could be produced at the LHC if it interacts weakly with the Standard Model. The search for dark matter can be performed directly, by looking for a signature of large missing transverse momentum coming from the dark matter candidates escaping the detector, measured against an accompanying visible object (jet, photon, boson). A broad and systematic search program covering these...
A Chern-Simons coupling with a gauge field is common in axion inflation. It is well known that this coupling leads to interesting phenomenology via the resonant production of helical gauge fields; e.g., gravitational wave, magnetogenesis, leptogenesis, etc. In this talk, we extend the previous analysis to the case where chiral fermions are charged under this gauge field which couples with the...
We express 6D SUGRA in terms of 4D N=1 superfields. This description is useful when we consider extra-dimensional models and derive their 4D effective theories. We consider 6D SUGRA compactified on the sphere and the torus with 4D branes, and solve the superfield equations of motion under the assumption that the background preserves N=1 SUSY. Such N=1 description of the background solution...
A summary of searches for heavy resonances with masses exceeding 1 TeV decaying into dibosons is presented, performed on data produced by LHC pp collisions at $\sqrt{s}$ = 13 TeV and collected with the CMS detector during 2016 and 2017. The common feature of these analyses is the boosted topology, namely the decay products of the considered bosons (both electroweak W, Z bosons and the Higgs...
We discuss a possibility that our electroweak vacuum is absolutely stable even if the top Yukawa coupling is larger than the critical value. Such a scenario can be realized without introducing new particles if we adopt a renormalization prescription which respects the asymptotic scale invariance at the quantum level. Instead, the theory becomes non-renormalizable and the perturbative unitarity...
Many extensions to the Standard Model, such as an extended Higgs sector, predict new particles decaying into two bosons (W, Z, gamma, H) making these important signatures in the search for new physics. Searches for such diboson resonances have been performed in final states with different numbers of leptons, photons and jets and b-jets where new jet substructure techniques to disentangle the...
We have investigated the constrained minimal supersymmetric standard model with three right-handed Majorana neutrinos whether there still is a parameter region which is consistent with all existing experimental data/limits such as Leptogenesis and the dark matter abundance and we also can solve the Lithium problem. Using Casas-Ibarra parameterization, we have found that a very narrow parameter...
Searches in CMS for dark matter in final states with invisible particles recoiling against leptons and photons are presented. Various topologies are explored, covering several specific dark-matter production modes. The talk focuses on the recent results obtained using data collected at Run-II of the LHC.
In this talk, we discuss the partial breaking of N=2 supergravity. It is known that the supersymmetric Dirac-Born-Infeld (DBI) type action appears as a Nambu-Goldstone mode of the partial breaking in the rigid N=2 theory. In this work, we try to reveal the supergravity couplings to the DBI type action on the basis of component and superspace approaches. We compare our action directly obtained...
The geometric phase (Pancharatnam-Berry phase) results from the geometrical properties of the parameter space of the Hamiltonian. In this paper, we show that the non-adiabatic Berry phase can generate the effective chemical potential, which can bias the matter and the antimatter number densities without introducing the derivative coupling of the field. Our scenario is consistent with
the...
How light can a fermion be if it has unit electric charge? We revisit the lore that LEP robustly excludes charged fermions lighter than about 100 GeV. We review LEP chargino searches, and find them to exclude charged fermions lighter than 90 GeV, assuming a higgsino-like cross section. However, if the charged fermion couples to a new scalar, destructive interference among production channels...
I will introduce a new set of effective field theory rules for constructing Lagrangians with $\mathcal{N} = 1$ supersymmetry in collinear superspace. In the standard superspace treatment, supersymmetry preservation is manifest at the Lagrangian level in part by the inclusion of auxiliary term components. By contrast, collinear superspace depends on a smaller set of coordinates and directly...
The search for dark matter can be performed indirectly at the LHC by looking for the intermediate mediators which would couple the dark matter particles to the Standard Model. The mediator could indeed decay to jets or leptons, leading to a resonant signature which can be probed. The talk will present the results of these searches with the ATLAS detector and show their complementarity with the...
The CMS detector explores a wide range of non-standard signatures including displaced and delayed particles, which allow to explore various beyond standard models and set limits of different exotic particles. Results based on data recorded in proton-proton collisions at sqrt(s) = 13 TeV will be reviewed.
Electroweakly charged dark matter always has charged partners. The mass differences between the dark matter and the partners are not so large and the they often have rather long lifetime, which can be seen in the collider experiments as a disappearing track. Based on 1703.09675 and ongoing works, I will discuss the current and future constraints for the minimal dark matter.
Searches for GUT-inspired heavy gauge bosons Z' have been so far carried out by assuming that they can decay according to Standard Model modes, namely dilepton and dijet final states. I will discuss Z' phenomenology in a U(1) extension of the MSSM, where it can decay into sleptons, squarks and gauginos, leading to final states
with charged leptons and missing energy. In particular, I will...
In spite of the vast literature on the subject of first order Electroweak Phase Transitions (EWPT), which can provide the necessary conditions for generating the Baryon Asymmetry in the Universe, fermion-induced EWPTs still remain a rather uncharted territory. In this talk, we consider a simple fermionic extension of the Standard Model (SM) involving one $SU(2)_L$ doublet and two singlet...
Many theories of beyond the Standard Model (BSM) physics predict unique signatures which are difficult to reconstruct and the background rates are also a challenge. Signatures from displaced vertices anywhere from the inner detector to the muon spectrometer as well as those of new particles with fractional or multiple value of the charge of the electron or high mass stable charged particles...
It is known that not every effective field theory could be embedded in quantum gravity, but only those which are consistent with the QG conjectures. Does these constraints have an impact in low energy physics? Recently, Ooguri and Vafa argued using a strong approach of the Weak Gravity Conjecture that non-supersymmetric stable AdS vacua are incompatible with quantum gravity. It is also known...
Anomalies in B-meson decays reported by the LHCb experiment could be explained by introducing a heavy neutral gauge boson Z' that dominantly couples to third generation quarks and second generation leptons. While the sensitivities of inclusive searches for such models are strong in heavy Z' regions (>500 GeV), the low-mass region sensitivity is degraded by large SM background (mostly Drell-Yan...
We present the results of the first global likelihood study of Dark Matter Simplified Models (DMSMs) performed by the MasterCode collaboration, considering the case of spin-1 and spin-0 mediators. Our study includes the most important collider limits coming from searches at runs 1 and 2 of the LHC, as well as constraints coming from cosmological data and direct searches for dark matter.
This...
Despite the absence of experimental evidence, Supersymmetry remains attractive from the theoretical and phenomenological point of view. In order to comply with the stringent experimental constraints, non-minimal realizations of the theory have to be considered. While typical studies are carried out assuming minimal flavour violation (MFV), I will focus on the hypothesis of non-minimal flavour...
I will provide a general overview of the collider phenomenology of spin 0 or 1/2 mediators with non-trivial gauge numbers under both the Standard Model and a single new confining group. Due to the possibility of many unconventional signatures, the focus is on direct production with semivisible jets. For the mediators to be able to decay, a global U(1) symmetry must be broken. This is best done...
The QCD axion, as well as more general Axion-Like Particles (ALPs) represent well motivated Dark Matter (DM) candidates. We investigate the possibility that a fraction of the total Axion DM abundance is made of Primordial Black Holes (PBHs). The basic ingredient is the existence of a long-lived network of axionic domain walls attached to strings, which eventually annihilates providing an extra...
The clockwork mechanism is an elegant framework to generate exponential hierarchies in a theory with only $O(1)$ numbers to start with. I will present some of the recent theoretical and phenomenological developments, first introducing the mechanism by using dark matter as an example of clockwork model building, then discussing the robustness of the clockwork solution to the hierachy problem...
Cosmological domain walls have been widely studied in numerical lattice simulations in the past. The main effort was to understand the dynamics of domain walls in the case of spontaneous breaking of global discrete symmetries which are often present in supersymmetric theories. It was found that networks formed by cosmological domain walls are (meta)stable if vacua between which walls...
We present an economical model of WIMP dark matter in which the dark sector consists of the dark matter candidate, a fermionic singlet, and its coannhihilation partner, a fermionic SU(2) n-plet with n>=3. The dark sector is coupled to the SM Higgs boson via non-renormalizable interactions. We map the viable parameter space of this model, taking into accounts constraints from direct detection...
We present the current perspectives for SUSY at the LHC in Run 2 and beyond, and at future colliders, in a phenomenological Minimal Supersymmetric Standard Model with eleven parameters (pMSSM11) and in the subGUT-CMSSM, where the input scale, $M_{in}$, at which the soft SUSY breaking terms are universal is treated as an additional free parameter in the sampling instead of being assumed to be...
In this talk I present a model with an enlarged color sector which solves the strong CP problem via new massless fermions. QCD color is unified with another non-Abelian group with a large confinement scale. The spontaneous breaking of the unified color group provides a source of naturally large axion mass due to small size instantons, and as a result no very light axions are present in the...
Missing Transverse Momentum is an extremely important quantity in the searches for RPC Supersymmetry. The accurate reconstruction of this quantity in high pile-up conditions is challenging. Missing transverse momentum is reconstructed from the vector sum of reconstructed objects. Energy from pile-up collisions enter jet cones altering the scale of jets and also increasing the resolution....
In this talk, we propose a novel scenario which simultaneously explains O(10)M? primordial black holes (PBHs) in the minimally supersymmetric standard model. Gravitational waves (GWs) events detected by LIGO-Virgo collaboration suggest an existence of black holes as heavy as 30Msol?. In our scenario, as seeds of the PBHs, we make use of the baryon number perturbations which are induced by the...
The Minimal Supersymmetric Standard Model (MSSM) predicts the existence of a total of four neutralinos, the lightest of which is one of the strongest cold dark matter (DM) candidates. The nature of this neutralino DM depends on the relative sizes of the bino, wino and higgsino mass parameters in the neutralino mass matrix. At the LHC, the trilepton channel, which is one of the most important...
The Peccei-Quinn (PQ) solution to the strong CP problem requires an anomalous global U(1) symmetry, the PQ symmetry. The origin of such a convenient global symmetry is quite puzzling from the theoretical point of view in many aspects. In this talk, we propose a simple prescription which provides an origin of the PQ symmetry. There, the global U(1) PQ symmetry is virtually embedded in a gauged...
The High-Luminosity Large Hadron Collider (HL-LHC) is expected to deliver an integrated luminosity of up to 3000 fb-1. The very high instantaneous luminosity will lead to about 200 proton-proton collisions per bunch crossing (“pileup”) superimposed to each event of interest, therefore providing extremely challenging experimental conditions. The sensitivity to find new physics Beyond the...
We study novel collider signatures including the Higgs boson and dark matter. These signatures arise naturally in well-motivated models, where dark matter interacts with the Standard Model primarily via the Higgs boson.
We explore concrete examples with fermion or scalar dark matter vis-a-vis our proposed search and the existing dark sector studies at the LHC. We also comment on the...
We consider D-term hybrid inflation in the framework of
superconformal supergravity. In part of the parameter space,
inflation continues for subcritical inflaton field value.
Consequently, a new type of inflation emerges, which gives
predictions for the scalar spectral index and the tensor-to-scalar
ratio that are consistent with the Planck 2015 results. The
potential in the...
Apart from the nonvanishing neutrino masses, state of the art experimental results in particle physics do not show direct evidence for Beyond Standard Model scenarios. This leaves us puzzled concerning the relation of the electromagnetic, weak, strong, and eventually of the gravitational interactions. On a theoretical basis, the local (extended) SUSY is considered to be a rather well-founded...
The striking discovery that the expansion of the Universe is not slowing down but accelerating has turned into one of the main mysteries in Cosmology. Large observational campaigns are being developed to seed light on this and other problems. I will briefly review this effort and then discuss The Dark Energy Survey (DES) : a state-of-the-art large-scale galaxy survey designed to understand,...
A future proton-proton collider with center of mass energy around 100 TeV will have a remarkable capacity to discover massive new particles and continue exploring weak scale naturalness. In this work we will study its sensitivity to two stop simplified models as further examples of its potential power: pair production of stops that decay to tops or bottoms and Higgsinos; and stops that are...
We present the current perspectives for supersymmetric Dark Matter, in light of current and future collider and direct detection experiments, in a phenomenological Minimal Supersymmetric Standard Model scenarios with eleven parameters (pMSSM11) and in the subGUT-CMSSM, in which the input scale, $M_{in}$, at which the soft SUSY-breaking terms are universal, is treated as an additional free...
Non-minimal composite Higgs (CH) models, with additional Goldstone
bosons (GB) beside the Higgs, do not only present a solution to the
hierarchy problem but could also shed light on the dark matter (DM)
puzzle. A realization of this scenario was presented in
(arXiv:1707.07685): The symmmetry breaking structure is SO(7)/SO(6) and
the DM is a complex GB, stabilized by an exact U(1). The...
Sparticls with smaller mass gaps are used successfully to understand the correct dark matter content of the universe. In this talk, I will discuss slepton pair-production processes with soft leptons (plus at least one jet) and small missing transverse energyassociated with a mass difference between the lightest neutralino and the lightest slepton (Δm) is ≲60 GeV. We utilize the angular...
The impact of the current searches at the LHC for monojets is compared to the current limits from direct searches for dark matter (DM) in the framework of the NMSSM. The DM annihilation cross section is ten orders of magnitude larger than limits on the scattering cross section. This can be explained, if the interactions are predominantly due to Higgs exchange, since the Higgs boson couples...
We work a scenario inspired by natural supersymmetry, where neutrino mass is explained within a seesaw scenario. We extend the Minimal Supersymmetric Standard Model by adding light right-handed neutrinos and their superpartners, the R-sneutrinos, and consider the lightest neutralinos to be higgsino-like.
We consider the possibility of having a R-sneutrino as lightest supersymmetric particle....
The inclusive cross-section for tW production in proton-proton collisions at $\sqrt{s} = 13$ TeV is measured of a dataset corresponding to an integrated luminosity of 35.9 fb$^{-1}$ collected by the CMS experiment. The measurement is performed using events with one electron and one muon in the final state along with at least one b-quark jet, and exploits kinematic differences between the...
The Higgs boson discovery stirred interest in next-to-minimal supersymmetric models, due to the apparent fine-tuning required to accommodate it in minimal theories. To assess their naturalness, we compare fine-tuning in a ℤ3 conserving semi-constrained Next-to-Minimal Supersymmetric Standard Model (NMSSM) to the constrained MSSM (CMSSM). We contrast popular fine-tuning measures with...
In the standard scenario, gravitinos couple to ordinary matter only
through the gravitational interaction, so that their couplings are
Planck suppressed. This implies a (quite) long lifetime.
In general, particles with long lifetimes generate some issues in cosmology since if they decay after the BBN, then their decay products may destroy light elements,
destroying therefore the successful...
We propose a Standard Model extension in which we consider the type-III 2HDM plus massive neutrinos and the horizontal flavor symmetry $S_{3}$ $(\nu$2HDM$\otimes S_3)$. In this extension and with the explicit sequential breaking of $S_{3}$ symmetry, all Yukawa matrices in the flavor adapted basis are represented by means of a matrix with two texture zeroes. The active neutrinos are considered...
The latest results of the measurement of the Higgs boson properties decaying into two photons with the full 2016 data, collected in pp collision at the center of mass energy 13 TeV at LHC will be presented. Signal strengths associated with the different Higgs boson production process, couplings to bosons and fermions, and effective couplings to photons and gluons are also to be discussed.
A classically conformal U(1)$^\prime$ extended Standard Model (SM)
is a simple and well-motivated extension of the SM,
where a new anomaly free U(1)$^\prime$ gauge symmetry is introduced
along with a U(1)$^\prime$ Higgs field $\Phi$ and three right-handed neutrinos.
In this model, the U(1)$^\prime$ gauge symmetry is broken
by the Coleman-Weinberg mechanism naturally at the TeV scale,...
We present full one-loop calculations for SUSY particle production at e+e- colliders. This includes hard and soft QED/QCD radiation and a proper treatment of complex phases. We show the relevance of the higher-order corrections for the extraction of the underlying SUSY parameters.
We propose a simple gauged U(1)x extension of the minimal supersymmetric Standard Model (MSSM), where R-parity is conserved as usual in the MSSM. The U(1)_X group is a linear combination of the B-L (baryon number minus lepton number) U(1) and the SM U(1)_Y hyper-charge gauge groups. Three MSSM singlet chiral multiplets with a unit U(1)_X charge are introduced, ensuring the model free from...
In Supersymmetric models with R-parity violation, depending on the coupling strength the lightest supersymmetric particle can be stable on detector level scales, long-lived, or decay promptly. We present a reinterpretation of ATLAS 13 TeV SUSY searches, originally designed for scenarios with either RPC or RPV with prompt LSP decays, in models with baryon-number-violating RPV with variable...
Many searches for supersymmetric particles are dedicated to either R-parity conserving (RPC) or R-parity violating (RPV) scenarios with prompt decays. However, a large range of coupling strengths are allowed, ranging from 0 (RPC limit) to theoretically estimated maximal values of order one. Varying these values over the entire possible range allows coverage of a rich phenomenology which can be...
Several possible extensions of the Standard Model predict the existence of a dark sector that is weakly coupled to the visible one: i.e. the two sectors couple via the vector portal, where a dark photon with mass in the MeV to GeV range mixes kinetically with the SM photon. If the dark photon is the lightest state in the dark sector, it will decay to SM particles, mainly to leptons and...
A search for supersymmetry is carried out in proton-proton collisions with a center of mass energy of 13 TeV and an integrated luminosity of 35.9 fb−1 collected with the CMS experiment at the CERN LHC. Events are selected by requiring one Higgs boson candidate decaying into two photons in association with at least one jet. Events are categorized according to the properties of the Higgs boson...
This contribution presents the search for the supersymmetric partner of the top quark in all-hadronic final states. The stop squark can be produced in pairs in the pp collisions produced in the LHC, and decay through different channels depending on the Supersymmetry (SUSY) parameters. This analysis focuses in the decays of the stop to top and neutralino, where the top quark decays...
Supersymmetry is one of the most searched-for extensions of the Standard Model. In its minimal realization, the Minimal Supersymmetric Standard Model, it predicts a new bosonic (fermionic) partner for each fundamental standard Model fermion (boson), as well as an additional Higgs doublet. The sector of sparticles with only electroweak interactions contains charginos, neutralinos, sleptons, and...
It is conjectured that flavor mixing furnishes a universal mechanism for the spontaneous breaking of supersymmetry. The conjecture is proved explicitly for the mixing of two chiral N = 1 supermultiplets and arguments for its general validity are given. That is an instance of the O’Raifeartaigh Lagrangian for which there is no tree-level nor perturbative breaking. Nonetheless, the dynamical...
We propose a novel mechanism of spontaneous supersymmetry breaking which relies upon a ubiquitous feature of Quantum Field Theory, vacuum condensates. Such condensates play a crucial role in many phenomena. Examples include Unruh effect, superconductors, particle mixing, and quantum dissipative systems. We argue that in all these phenomena supersymmetry, when present, is spontaneously...
Search for electroweak production of supersymmetric particles in scenarios with compressed mass spectra, using the final state with two low-momentum leptons of same flavour and opposite charge, and missing transverse momentum, is presented. Results are interpreted using the R-parity conserving models with small mass difference between the produced particles and the lightest neutralino....
