Physics at LHC 2012

3 Jun 2012, 16:00 → 9 Jun 2012, 14:00 Canada/Pacific

Life Sciences Centre, UBC

Guenakh Mitselmakher (U Florida, USA), Robert McPherson (U Victoria, BC, Canada)

Sunday, 3 June

Arrival and Registration

Public Lecture: Rolf Heuer

Public lecture by Rolf Heuer on the LHC

Monday, 4 June

Registration

1A: Welcome, LHC Machine

Convener: Alan Astbury (University of Victoria)

1 Welcome & Information

Speaker: Robert McPherson (University of Victoria)

Slides VancouverPLHC.pdf VancouverPLHC.pptx

2 Opening Talk

Speaker: Rolf Heuer (CERN)

Slides PLHC-Opening.pdf PLHC-Opening.pptx

3 Status and plans of the LHC

Speaker: Steve Myers (CERN)

Slides 120604_Myers_PLHC_Vancouver_AS_PRESENTED.pdf 120604_Myers_PLHC_Vancouver_AS_PRESENTED.pptx

10:50 Coffee Break

1B: LHC Experiments I

Convener: Dugan O'Neil (Simon Fraser University)

4 Status and plans of ALICE

This talk will focus on the recent results obtained with the ALICE experiment during the heavy ion and pp runs. In comparing the data obtained in pp collisions with the Pb-Pb data we'll discuss the modification of high p_T particles traversing the hot and dense medium. We will present data on the bulk properties of the medium created in such collisions, discuss flow observables, particle production as well as spectra of identified particles out to large transverse momenta.

Speaker: Paul Kuijer (NIKHEF (NL))

Slides kuijer_plhc2012_0406.pptx

5 TOTEM status and results

The TOTEM experiment at the LHC has measured the total proton-proton cross-section and the differential elastic cross-section at the energy of $\sqrt{s} = 7$ TeV. The data were collected with the two inelastic telescopes and the Roman Pot detectors during several dedicated runs, partly with a special high-$\beta^*$ beam optics. The elastic scattering measurements cover a range of squared four momentum transfer $|t|$ from 0.02 to $2.5 \mathrm{GeV}^2$ and exhibit an approximately exponential behaviour for $|t| < 0.33 \mathrm{GeV}^2$, followed by a significant diffractive minimum at $|t| = (0.53 \pm 0.01_\mathrm{stat} \pm 0.01_\mathrm{syst}) \mathrm{GeV}^2$. For $|t| > 1.5 \mathrm{GeV}^2$, a power-law decrease with an exponent of $-7.8 \pm 0.3_\mathrm{stat} \pm 0.1_\mathrm{syst}$ was observed. The total cross section has been measured with four different methods: three of them make use of the luminosity measurement provided by CMS, while one is luminosity independent and utilizes the separate measurement of the elastic and inelastic rate. Furthermore, the charged particle pseudorapidity density $dN_{ch}/d\eta$ has been measured in the range $5.3 < \eta < 6.5$.

Speaker: Fabrizio Ferro (INFN - Genova)

Proceedings ff-totem-plhc2012.tar

Slides totem-ff-plhc2012.pdf

6 Status and plans of ATLAS

Speaker: David Strom (University of Oregon (US))

Slides atlas-status.pdf atlas-status.pptx

12:40 Lunch

1C: LHC Experiments II

Convener: Anadi Canepa (TRIUMF)

7 Status and plans of LHCb

Speaker: Roger Forty (CERN)

Proceedings

• Fig1.eps
• Fig2.eps
• Fig3.eps
• Fig4.eps
• forty.pdf
• forty.tex

Slides PLHC-Forty.pdf PLHC-Forty.pptx

8 Reconstructing jets, missing energy, taus in CMS

Speaker: Keti Kaadze (CERN)

Paper ProceedingsPLHC2012.tar

Slides KetiKaadze-PLHC2012.pdf

9 Neutral particles energy spectrum for 900 GeV and 7 TeV p-p collisions as measured by the LHCf experiment

The Large Hadron Collider (LHC) gives us a unique opportunity to study hadron interactions at the collision energy of 10^17 eV in the laboratory system. The data collected so far by the LHCf experiment is proving instrumental in increasing our comprehension of the chemical composition of Ultra High Energy Cosmic-Rays (UHECRs) by improving hadron interaction models used in air shower simulations of UHECRs. The analysis has now reached a stage where results can be presented and energy and p_T spectra of various neutral particles can be shown. The data has been collected at centre of mass energies of 900 GeV and 7 TeV. In the talk an outlook will also be given on future collider runs with proton-ions and proton-proton at centre of mass energies of 14 TeV.

Speaker: Dr Raffaello D'Alessandro (Universita di Firenze and INFN-Firenze)

Paper article.pdf

Proceedings Latex and figures

Slides 2012_06-PLHC_LHCf_V05.pdf

10 Results from particle identification in pp collisions measured with ALICE at the LHC

ALICE is the LHC experiment dedicated to the study of Heavy-Ion collisions. Many observables related to the properties of the medium created in such collisions rely on the excellent capabilities of the detector in terms of Particle Identification (PID). In this talk, the various PID techniques used for the different ALICE analyses will be described. Focus will be given to the detector performance and selected results will be presented for pp collisions at sqrt(s) = 7 TeV and Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV.

Speaker: Chiara Zampolli (Universita e INFN (IT))

Paper CZampolli_PLHC_v3.pdf Proceedings - source and figures

Slides

• C_Zampolli_PLHC_Mod.pdf
• C_Zampolli_PLHC_Mod.pptx
• C_Zampolli_PLHC.pdf

1D: Poster Session and Coffee Break

slides Posters.pdf Posters.pptx

11 4th generation searches at ATLAS

Top-quark precision measurements are of central importance to the LHC physics program. The top-quark is the heaviest known fundamental particle with unique properties within the Standard Model (SM). Its large couplings to the Higgs boson, and being the only quark that decays before hadronisation make it sensitive to new physics beyond the SM. Among the places to look for deviations from the SM are new quarks families that can appear as a fourth family with Higgs, a “strong” fourth family without Higgs or vector-like quarks. A potential extension for the SM would be the adjonction a 4th family of heavy chiral fermions that could provide new sources of CP violation to explain the matter-antimatter asymmetry in the Universe, and allow for a heavier Higgs boson while remaining consistent with other precision electroweak studies. This poster will review various searches for 4th generation quarks performed using data collected in 7 TeV LHC proton-proton collisions with the ATLAS detector.

Speaker: Dennis Patrick Wendland (Institut fuer Physik)

Proceedings

• article.pdf
• article.tex
• singlelep_bprime_bins.eps
• singlelep_bprime_limit.eps

Slides poster_4thGen_PLHC2012.pdf

12 A search for new physics in events with Z bosons, jets, and missing transverse energy

We present a search for new physics in the final state of a leptonically decaying Z boson and missing transverse energy (MET) utilizing the full 2011 dataset collected by the CMS detector. Two complementary search regions are investigated. The first requires a leptonic Z and two or more jets, and searches in the high MET tail. The second applies additional requirements to increase sensitivity to electroweak production of new physics. These requirements include a veto on b tagged jets and a cut on the dijet invariant mass to select jets from a W or Z decay, both of which highly suppress Standard Model (SM) backgrounds. These searches are sensitive to a variety of new physics scenarios involving Z bosons, including electroweak production of particles which decay to Zs. Fake MET from SM Z+Jets background is modeled using a data driven MET templates technique, and ttbar background is predicted using opposite flavor dilepton events.

Speaker: Warren Andrews (Univ. of California San Diego (US))

proceedings

• metplot_2jets.pdf
• proceedings_warren.pdf
• proceedings_warren.tex

Slides poster_z_met_templates_warren.pdf

13 A search for ttbar resonances in the di-lepton channel with the ATLAS detector in 2.05/fb of pp collisions at sqrt(s) = 7 TeV

A search for top quark pair ttbar resonances in final states where both W bosons from the top quark decay into either an electron and electron-neutrino or a muon and muon-neutrino (dilepton final state) has been performed. The data were recorded by the ATLAS experiment at the CERN Large Hadron Collider. The search uses a data sample corresponding to an integrated luminosity of 2.05 fb-1, which was recorded in 2011 at a proton-proton centre-of-mass energy of 7 TeV. No evidence for a resonance is found. Upper limits at the 95% Confidence Limit (C.L) are set on the production cross-section times branching ratio of the resonance decaying to ttbar pairs as a function of the resonance pole mass.

Speaker: Michele Petteni (SFU Simon Fraser University (CA))

Paper proceedings plhc_proceeding_mp.tex

Slides ATL-COM-PHYS-2012-653_09-18-26.pdf

14 Asymptotically safe electroweak interactions

In absence of a fundamental Higgs boson, the dynamics of the SU(2)xU(1) symmetry breaking can be described by coupling gauge bosons and fermions to a nonlinear sigma model. Normally this is regarded only as an approximate description valid up to some cutoff energy scale. However, if there is a UV fixed point, this model in which the Nambu-Goldstone bosons can be thought of as fundamental degrees of freedom could hold up to higher energies, becoming asymptotically safe. The RG analysis of the electroweak nonlinear sigma model, the predictions about the contributions to the oblique S and T parameters and the computation of the scattering amplitude within the asymptotic safety scenario will be presented. Inclusion of fermions will also be discussed.

Speaker: Mr Alberto Tonero (SISSA)

Poster Poster1b.pdf

15 ATLAS Higgs search in the $H \to WW^*$ decay mode using 4.7 fb$^{-1}$

Speaker: Doug Schouten (TRIUMF (CA))

Poster poster.pdf

16 Combining b-tagging calibrations in ATLAS

The ATLAS collaboration calibrates its b-tagging algorithms using a number of data-driven methods. The b-tagging algorithms, used to separate b-quark jets from light-quark jets, are widely used in top, Higgs, and Exotics analyses in ATLAS. The algorithm’s performance is measured for light-quark jets, charm jets, and bottom jets. In some cases multiple methods can be used to measure the performance: methods using di-jet data and a pure sample of top-quark pair production are be used to measure the bottom-quark jet performance. These methods have complementary strengths – the di-jet methods tend to have the smallest errors at low jet energy, and the ttbar methods tend to have smaller errors at high jet energy. We used a minimum likelihood method to fit the results, profiling common systematics, to combine the results. For results on common data we have also understood the statistical correlation of our methods. This poster will describe the details of the combination.

Speaker: Gordon Watts (University of Washington (US))

Paper ATLAS approve draft of PLHC proceedings for this b-tagging combination poster papersource.zip

Poster Combining_b-tagging_Calibrations_Poster.pdf Combining_b-tagging_Calibrations_Poster.pptx

17 Contact Interactions (non resonant dilepton final state searches)

A wide range of new physics phenomena can produce modifications to the dilepton mass spectra predicted by the standard model (SM) such as quark/lepton compositeness, extra dimensions, and new gauge bosons. The predicted form of these deviations is often either a resonance or an excess in the number of events in the spectra at high mass. This work presents a search for contact interactions in the dielectron and dimuon channels using data from proton-proton collisions produced by the LHC at sqrt(s) = 7 TeV and recorded by the ATLAS detector. The data sample, collected in 2011, corresponds to an integrated luminosity of 5 fb-1. No significant deviations from the standard model are observed. Using a Bayesian approach, we set 95% CL lower limits on the energy scale of llqq contact interactions.

Speaker: Vikas Bansal (University of Victoria (CA))

Poster Vikas_Bansal_CIee_PLHC12_poster.pdf

Proceedings

• article.tex
• econfmacros.tex
• mass_elec.eps
• mass_muon.eps
• Proceedings

18 Measurement of polarisation amplitudes and triple product asymmetries in the $B_s \to \phi \phi$ decay at LHCb

An untagged, time-integrated analysis of the $B_s \to \phi \phi$ decay has been performed with 1 fb$^{-1}$ of pp collision data at centre-of-mass energy $\sqrt{s} = 7$ TeV taken using the LHCb detector. Optimised selections have yielded 801 $B_s \to \phi \phi$ events at high signal to background ratio. This has allowed for measurements of polarisation amplitudes ($|A_0|^2$, $|A_\perp|^2$, $|A_\parallel|^2$) and strong phase difference (cos$\delta_\parallel$) to be performed. T-violating triple product asymmetries have yielded results $A_U=-0.055 \pm 0.036\mathrm{(stat.)} \pm 0.018\mathrm{(syst.)}$ and $A_V = 0.010 \pm 0.036\mathrm{(stat.)} \pm 0.018\mathrm{(syst.)}$.

Speaker: Sean Benson (University of Edinburgh (GB))

Proceedings PLHCFormat_PhiPhi.pdf PLHCFormat_PhiPhi.tex

Slides PLHC-phiphi.pdf

19 Measurement of the top quark pair production cross section with ATLAS in pp collisions at √s = 7 TeV using final states with an electron or a muon and a hadronically decaying tau lepton

We present a measurement of the top-quark pair production cross-section in the tau+lepton channel in proton-proton collisions at 7 TeV with the ATLAS detector at the Large Hadron Collider. Events with an isolated electron or muon and a tau lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. To identify tau leptons, the analysis uses a multivariate technique based on boosted decision trees.

Speaker: Jennifer Lynn Godfrey (SFU Simon Fraser University (CA))

20 Measurement of top quark differential cross sections at sqrt(s) = 7 TeV

We present measurements of various differential cross sections in top pair production in proton-proton collisions at the LHC at a centre-of-mass energy of 7 TeV. The data are collected by the CMS experiment during the year 2011. Cross sections are measured differentially as a function of various variables, including the transverse momentum and rapidity of the (anti)top quark as well as the top-antitop system, as well as multiplicity and transverse momenta of jets produced in addition to the top pair. The cross sections are corrected for detector effects to the level of stable particles. The results are compared with various Monte Carlo models, as well as with theory predictions. The overall consistency of the features of top pair production with expectations from the standard model is investigated.

Speaker: Mr Wolf Behrenhoff (Deutsches Elektronen-Synchrotron (DE))

Poster CrossSectionPoster-spellfix.pdf

21 Measuring the b-jet tagging efficiency on c-jets containing D* mesons with ATLAS data

The identification of jets originating from b-quarks (b-tagging)is a crucial tool for the LHC physics program, both for precision measurements and in searches for new particles. One important ingredient when using b-tagging in physics analyses is the determination of the probability to mistakenly b-tag a jet originating from a c-quark (c-tag efficiency). The optimal sample for the measurement of the c-tag efficiency would be a clean sample of jets originating from c-quarks. The sample of jets associated to reconstructed $D^*$ mesons (through the decay chain $D^* \to D^0(K \pi \pi)$ is quite close to this ideal case since most $D^*$ mesons originate from c-quark hadronization. The c-tag efficiency has been measured by comparing the reduction in the yield of $D^*$ mesons before and after the b-tagging requirement of the associated jet. The contamination from $D^*$ mesons that originate from b-hadron decays has been taken into account using a fit to the $D^0$ pseudo-proper time distribution.

Speaker: Andrea Ferretto Parodi (Sezione di Genova)

Proceedings

• ferretto.pdf
• ferretto.tex
• fig_01d.eps
• fig_02a.eps
• fig_05a.eps
• fig_05b.eps

Slides ferretto-poster.pdf

22 Measuring the b-jet tagging efficiency using samples of jets containing muons with ATLAS data

The identification of jets originating from b-quarks, referred to as b-tagging, is an important part of the LHC physics program. In precision easurements in the top quark sector as well as in the search for the Higgs boson and new phenomena, the suppression of background processes containing predominantly light-flavour jets using b-tagging is of great use. In order for b-tagging to be used in physics analyses the efficiency with which a jet originating from a b-quark is tagged by a b-tagging algorithm needs to be measured. The b-tag efficiency can measured with two complementary methods in a sample of jets containing muons by exploiting the transverse momentum of the muon with respect to the jet axis (pTrel). One method fits pTrel emplates to the data to extract the fraction of b-jets in the sample before and after b-tagging while the other method makes use of two samples with different vour composition and two uncorrelated b-tagging algorithms.

Speaker: Christian Andreas Jung (Technische Universitaet Dortmund (DE))

Proceedings

• article.tex
• ATL-PHYS-PROC-2012-169.pdf
• MV170efficiencyPt.pdf
• System8_bTagEff_MV170_DefaultFit.pdf

Slides poster.pdf

23 Measuring the b-jet tagging efficiency using top anti-top events with ATLAS data

Many physics analyses with the ATLAS detector expect to have jet originating from b-quarks in the final state. Algorithms that allow to identify such jets are thus of great importance and it is crucial to understand their performance with data-driven measurements of efficiencies and fake rates. Since the top quark almost exclusively decays to a W boson and a b-quark, a sample of top anti-top events is ideal for studying the b-tagging performance. Final states containing one or two leptons have been used to measure the b-tagging efficiency, either by counting the number of b-tagged jets or by applying kinematical fit methods to extract a pure sample of b-jets. The calibration methods based on top anti-top events are especially important because they can provide measurements of the b-tagging efficiency also for jets with high momentum.

Speaker: Dominik Duda (Fachbereich C / Physik)

Paper

• fig_13a.eps
• fig_13b.eps
• fig_17b.eps
• proceedings_dduda.pdf
• proceedings_dduda.tex

Slides poster_plhc_version38.pdf

24 Observation of CP violation in $B^\pm \to DK^\pm$ decays at LHCb

An analysis of $B^\pm \to DK^\pm$ and $B^\pm \to D\pi^\pm$ decays is presented where the D meson is reconstructed in the two-body final states: $K^\pm \pi^\mp$, $K^+K^−$ and $\pi^+\pi^-$. Using 1.0 fb$^{−1}$ of LHCb data, measurements of several observables are made including the first observation of the suppressed mode $B^\pm \to [\pi^\pm K^\mp] DK^\pm$. CP violation in $B^\pm \to DK^\pm$ decays is observed with $5.8\sigma$ significance. We also comment on the prospects for similar measurements using different final states.

Speaker: Daniel Johnson (University of Oxford (GB))

Proceedings article.pdf DJohnson_Poster_Proceedings.tgz

Slides PLHC_DJohnson_v3a.pdf

25 Parameters of the neutrino sector in tau decays

The smallness of the neutrino masses can be well understood within the seesaw mechanism (type I). After spontaneous symmetry breaking of the Standard Model gauge group one obtains a $(n_L+n_R)\times(n_L+n_R)$ Majorana mass matrix $M_\nu$ for neutrinos. The mixing between the $n_R$ right-handed neutrino singlets and the neutral parts of the $n_L$ lepton doublets gives masses for the neutrinos which are of the size expected from neutrino oscillations. The diagonalization of the mass matrix gives rise to a split spectrum consisting of heavy and light states of neutrinos given by $U^T M_\nu U=\mathrm{diag}(m_l,m_h)$. For the case $n_R=1$ we diagonalize the neutral fermion mass matrix with a rotation matrix $U$ determined by three complex angles. For the case $n_R=2$ we parameterize the mass matrix with a rotation matrix $U$ determined by two complex angles and for the diagonalization we apply the Grimus-Lavoura ansatz. In both cases we take $n_L=3$. We calculate the 1-loop radiative corrections to the mass parameters of the neutrino sector of the seesaw extension of the Standard Model which produce mass terms for the neutral leptons. With these ingredients we plan to look at the process $W^\pm \to \tau^\pm + \nu \to h_1^\pm + h_2^\mp + h_3^\pm +\nu+\nu$ and plan to study the $\tau$ polarization coming from the decay of a $W$ boson in the data of the CMS experiment at LHC and thus determine restrictions to the parameters of the neutrino sector.

Speaker: Darius Jurciukonis (Vilnius University (LT))

Poster PLHC2012.pdf

Proceedings Proceedings_PLHC2012_correct.pdf Proceedings_PLHC2012_correct.tex

26 Physics with tau lepton final states in ATLAS

Physics involving tau lepton signatures form an integral part of the ATLAS physics program, and are becoming more prevalent, given the large amounts of data accumulated in 2011 and 2012 LHC running. This talk reviews the increased sensitivity of searches for a Standard Model Higgs boson in the low mass region, as well as searches for neutral and charged supersymmetric Higgs bosons, decaying to tau final states. Other searches involving tau lepton signatures are also reviewed, including searches for heavy gauge bosons, leptoquarks, and supersymmetric decays. Standard Model processes from W, Z, and top pair production involving tau leptons are also investigated.

Speaker: Daniele Zanzi (Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut) (D)

27 Quark contact interactions at the LHC

Quark contact interactions are an important signal of new physics. A model in which the presence of a symmetry protects these new interactions from giving large corrections in flavor changing processes at low energies is introduced. It provides the basic set of operators which must be considered to contribute to the high-energy processes. The discussion of their experimental signature at the LHC, in the case where the number of contributing operators are just two, will be presented. For a representative integrated luminosity of 200 inverse pb and 7 TeV of center of mass energy, is it possible to show that the presence of two operators significantly modifies the bound on the characteristic energy scale of the contact interactions which is obtained by keeping a single operator.

Speaker: Mr Alberto Tonero (SISSA/INFN)

Poster Poster2c.pdf

proceedings proceedings.pdf proceedings.tar.gz

28 Search for $B^0_s \to \mu^+\mu^−$ and $B^0 \to \mu^+\mu^−$ decays at LHCb

A search for $B^0_s \to \mu^+\mu^−$ and $B^0_s \to \mu^+\mu^−$$ decays is performed using 1.0 fb$^{−1}$ of pp collision data collected at $\sqrt{s}=7$ TeV with the LHCb experiment at the Large Hadron Collider. For both decays the number of observed events is consistent with expectation from background and Standard Model signal predictions. Upper limits on the branching fractions are determined to be BR$(B^0_s \to \mu^+\mu^−) < 4.5 (3.8) \times 10^{−9}$ and BR$(B^0 \to \mu^+\mu^−) < 1.0 (0.81) \times 10^{–9}$ at 95\% (90\%) confidence level.

Speaker: Cosme Adrover Pacheco (CPPM - Universite d'Aix - Marseille II (FR))

Figures bdt.pdf events.pdf

Poster adrover_poster_Bsmumu.pdf

Proceedings article.pdf article.tex

29 Search for a light Higgs Boson at Babar

Babar collided electrons and positrons at a centre of mass energy of ~10GeV at the Stanford Linear Accelerator Center. A light CP-odd Higgs boson is expected in extensions to the Standard Model such as Next to Minimal Supersymmetry. The Babar Collaboration searched for a light Higgs boson (A0) produced in radiative decays of an Υ meson (Υ → γA0). We saw no evidence of the A0 decaying into mu+mu-, tau+tau-, hadrons, or invisible final states with a sample of 122 million Υ(3S), 99 million Υ(2S), and 23 million Υ(1S) from Υ(2,3S) decays collected at the PEP II B-factory. We set upper limits on product branching fractions B(Υ→γA0)xB(A0→various states) as low as 10^-6 for A0 masses from threshold up to 9GeV/c^2. As a result, we exclude a large fraction of parameters space for Next to Minimal Supersymmetry. Some searches are published and a few is still in the analysis stage. I will present work done by the collaboration as well as my work in progress for Υ(1S)→ γA0;A0→hadrons.

Speaker: Mr Rocky So (University of British Columbia)

Poster rockyPLHC2012.pdf

Proceedings

• article.tex
• econfmacros.tex
• rockysoPLHC2012proceedings.pdf
• tanbeta10mumu.eps
• tanbeta10tautau.eps

30 Search for charged Higgs bosons decaying via $H^+ \to \tau\nu$ in 7 TeV pp colllisions with the ATLAS detector

Speaker: Anna Katharina Kopp (Albert-Ludwigs-Universitaet Freiburg (DE))

Paper

• article2.pdf
• article2.tex
• limit_combined.eps
• limit_mhmax.eps

Slides Poster.pdf

31 Search for heavy neutrinos with the ATLAS detector

The discovery of neutrino oscillations established that neutrinos have non-zero mass and provided clear evidence for physics beyond the Standard Model. One possible explanation for the mass of light neutrinos is provided by theoretical models based on ideas of Grand Unification. Such models usually introduce additional neutrino fields, which manifest themselves as the new heavy particles that could be detected directly. In this poster we describe a search for hypothetical heavy neutrinos and right-handed gauge bosons in events with two high transverse momentum leptons and at least one high transverse momentum hadronic jet. The results were obtained from data corresponding to an integrated luminosity of 2.1fb-1 collected in 2011 in proton-proton collisions at 7 TeV with the ATLAS detector at the CERN Large Hadron Collider.

Speaker: Matthew Ryan Relich (Department of Physics-University of California Irvine)

32 Search for long-lived massive particles at CMS

Several models of new physics, including split supersymmetry, predict the existence of a heavy particle, which is long-lived on the timescales of the bunch spacing of the Large Hadron Collider (LHC). Such a particle would be observable using the Compact Muon Solenoid (CMS) at the LHC, and although produced at high momentum, it would travel slowly due to its large mass. We describe a search for these particles, using the experimental techniques of time of flight and dE/dx measurement. Results are presented based on data recorded with CMS in 2011.

Speaker: Seth Cooper (School of Physics and Astronomy)

Proceedings

• article.pdf
• article.tex
• Distrib_I_tktof.eps
• Distrib_Pt_tktof.eps
• Distrib_TOF_tktof.eps
• ExclusionPlot_tkonly.eps
• ExclusionPlot_tktof.eps

Slides hscp_poster_v2.pdf

33 Search for massive long-lived exotic particles with the ATLAS detector

A search for massive long-lived charged particles, performed using data recorded from pp collisions at sqrt(s) = 7 TeV collected by the ATLAS detector at the LHC, is presented. The velocity of high momentum particles is measured based on time-of-flight and anomalous ionisation energy loss, and the particle mass is estimated from the measured velocity and momentum. Based on a data sample using the full 2011 data set different combinations of sub-detectors are used to search for of stable gluinos, squarks, and sleptons.

Speaker: Christopher Marino (University of Victoria)

Poster PLHC_poster_draft7.pdf

Proceedings

• article.tex
• hv_fig_03.eps
• pixel_fig_08.eps
• PLHC2012_proceedings.pdf

34 Search for supersymmetric particles using final state with one lepton, jets and missing transverse momentum with ATLAS detector

A search for supersymmetric particles using final states with one lepton, jets and a large missing momentum is presented. The analysis uses the full dataset (4.7 fb$^{-1}$) recorded by the ATLAS detector at $\sqrt{s} = 7$ TeV in 2011. The results are used to derive constraints on gluino and squark masses.

Speaker: Yuichi Sasaki (University of Tokyo (JP))

Poster Poster_v7.pdf

Proceedings

• 3jets.eps
• 4jets.eps
• article.pdf
• article.tex
• limit.eps

35 Search for supersymmetry in events with four or more leptons in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

Results of a search for supersymmetry in events with at least four electrons or muons in the final state are presented. The search is performed in sqrt(s) = 7 TeV proton-proton collision data delivered by the LHC and recorded by ATLAS. Results are obtained in various signal regions and interpreted in terms of R-parity violating Minimal Supergravity models.

Speaker: Estel Perez Codina (TRIUMF (CA))

Paper Proceedings

Slides FourLepPoster_V8.pdf

36 Search for supersymmetry in final states with a single lepton, b-jets and missing transverse energy in proton-proton collisions at 7 TeV

Motivated by supersymmetric models with light top and bottom squarks, a search for supersymmetry in final states with a single lepton, b-jets and missing transverse energy is performed. The analysis is based on data recorded at a center of mass energy of 7 TeV during 2011, corresponding to an integrated luminosity of 4.96/fb. Results are interpreted in the context of the constrained Minimal Supersymmetric Standard Model and different heavy flavor simplified models.

Speaker: Niklas Andreas Pietsch (UHH - Institute for Experimental Physics)

Poster poster.pdf

Proceedings

• CMSSM.eps
• proceedings.pdf
• proceedings.tex
• T1tttt.eps

37 Search for the Standard Model Higgs boson in the $H \to \tau^+ \tau^-$ decay mode with 4.7 fb$^{-1}$ of ATLAS data at $\sqrt{s} = 7$ TeV

Speaker: Noel Dawe (SFU Simon Fraser University (CA))

38 Search measurement of t-channel single top-quark production with the ATLAS detector

The electroweak production of singly produced top quarks at the LHC operating at a center of mass energy of sqrt(s) = 7 TeV is dominated by the t-channel exchange of a virtual W boson that is emitted by a light quark inside one of the colliding protons. Thus, the measurement of the top-quark and top-antiquark production cross sections is sensitive to the u-quark PDF and the d-quark PDF for a momentum fraction x of the incoming light quarks and can provide complementary input to constrain these PDF in the range of 0.02 < x < 0.5. Furthermore, the cross section is proportional to the square of the CKM matrix element |Vtb| and the measurement can thus provide additional input to constrain the quark mixing matrix without assumptions on the number of quark generations.

Speaker: Kathrin Becker (Bergische Universitaet Wuppertal (DE))

Poster PLHC_2012_posterA0_horizontal_new.pdf

Proceedings

• article.pdf
• article.tex
• rtop.eps

39 Searches for supersymmetry and UED in events with three-leptons and missing transverse momentum with ATLAS

We present a search for supersymmetry and universal extra dimensions (UED) in events with three electrons or muons and missing transverse momentum. The analysis is based on sqrt(s) = 7 TeV proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. The results are interpreted in a UED model and in terms of direct production of weak gauginos in R-parity conserving phenomenological MSSM and simplified models.

Speaker: Samuel King (University of British Columbia (CA))

Proceedings

• article.pdf
• article.tex
• econfmacros.tex
• MSSM_SR1_PRL_apr17.eps
• smA0_SR1_xs_PRL_apr17.eps

40 SM Higgs in bb searches with the ATLAS detector at the LHC

Speaker: Dr Mario Martinez-Perez (Universitat Autònoma de Barcelona (ES))

Slides poster_PLHC2012_Hbb.pdf

41 Study of the ATLAS muon identification efficiency in the presence of high pile-up

In 2012 the LHC will be operated in a mode leading to up to 40 inelastic pp collisions per bunch crossing, so-called "pile-up". The reconstruction and identification of muons produced in a hard collisions is difficult in this challenging environment. Di-muon decays of J/psi mesons and Z bosons have been used to study the muon reconstruction and identification efficiency of the ATLAS detector as a function of the muon transverse momentum from p_T =4 GeV to p_T = 100 GeV and the number of inelastic collisions per event. The results show a steep efficiency turn-on curve reaching its plateau value of 100% at p_T approx 6 GeV and no dependence of the muon reconstruction efficiency on the amount pile-up. The studies also reveal that the use of inner detector tracks allows us to distinguish between isolated muons and non-isolated muons produced in jets with high separation power even at the highest pile-up levels.

Speaker: William Robert Spearman (Harvard University (US))

LaTeX

• article.tex
• fig05-eps-converted-to.pdf
• fig14a-eps-converted-to.pdf
• fig14c-eps-converted-to.pdf
• PLHCProceedings.zip

Proceedings ATL-MUON-PROC-2012-007.pdf

Slides ATLASMuonReconstruction8.pdf ATLASMuonReconstruction8.pptx

42 SuperB - a next generation flavor factory

Speaker: Christopher Hearty (University of British Columbia)

43 The ATLAS Tile Calorimeter performance at LHC

The Tile Calorimeter (TileCal), the central section of the hadronic calorimeter of the ATLAS experiment, is a key detector component to detect hadrons, jets and taus and to measure the missing transverse energy. Due to the very good muon signal to noise ratio it assists the spectrometer in the identification and reconstruction of muons. TileCal is built of steel and scintillating tiles coupled to optical fibers and read out by hotomultipliers. The calorimeter is equipped with systems that allow to monitor and to calibrate each stage of the readout system exploiting different signal sources: laser light, charge injection and a radioactive source. The calorimeter performance and its stability has been evaluated with the rich sample of collision data in 2011 but also with calibration data, random triggered data, cosmic muons and splash events. Results on the absolute energy scale calibration precision, on the energy and timing uniformity, on the time resolution and on the synchronization precision are presented. Besides, the TileCal minimum bias current readout provides a precise monitoring of the instantaneous luminosity. The results demonstrate that the Tile Calorimeter is performing well within the design requirements and is giving essential input to the physics results.

Speaker: Mihai Cuciuc (Horia Hulubei National Institute of Physics and Nuclear Enginee)

Slides ATLAS_TileCal_Performance.pdf

44 The LHCb upgrade

The LHCb experiment is designed to perform high-precision measurements of CP violation and search for New Physics using the enormous flux of beauty and charmed hadrons produced at the LHC. The operation and the results obtained from the data collected in 2010 and 2011 demonstrate that the detector is robust and functioning very well. However, the limit of ~1 fb–1 of data per year cannot be overcome without improving the detector. We therefore plan for an upgraded spectrometer by 2018 with a 40 MHz readout and a much more flexible software-based triggering system that will increase the data rate as well as the efficiency, especially in the hadronic channels.

Speaker: Silvia Borghi (University of Glasgow (GB))

Proceedings

• article.pdf
• article.tex
• Fig_schedule.eps

Slides PosterLHCbUpgrade_Borghi_PLHC2012_a0.pdf

45 The reconstruction and identification of hadronically decaying tau leptons at ATLAS

Tau leptons play an important role in the physics program at the LHC. They are used not only in searches for new phenomena like the Higgs boson or Supersymmetry and electroweak measurements but also in detector related studies like the determination of the missing transverse energy scale. Optimal identification of hadronically decaying tau leptons is achieved by using detailed information from tracking and calorimeter detector components. Variables describing the properties of calorimeter energy deposits and track reconstruction within tau candidates are combined in multi-variate discriminants, to achieve high rejection against backgrounds. The identification efficiencies are measured by W to tau nu and Z to tau tau events, and compared with the prediction of the Monte Carlo simulation. The energy scale uncertainties for tau leptons are determined by investigating single hadron calorimeter response, as well as kinematic distributions in Z to tau tau events.

Speaker: SUSIE Bedikian (Yale University (US))

Slides Bedikian_PLHCPoster_Final_June2012.pdf

1E: Physics Objects and/or Breaking News

Convener: Michel Lefebvre (University of Victoria)

46 Flavour tagging at LHCb

The identification of the flavour of reconstructed Bd and Bs mesons at production is necessary for the measurements of oscillations and time-dependent CP asymmetries. The calibration and performance of opposite-side flavour tagging algorithms have been developed using simulated events and optimized and calibrated with different flavour specific B decays with ~1 fb–1 of data collected in pp collisions at √s=7 TeV during the 2011 physics run. Using flavour tagging LHCb has performed, among others, new measurements of Delta m_s, of the CP violating Bs mixing phase φs and of direct and mixing-induced CP violation in B->hh decays.

Speaker: Miriam Calvo Gomez (University of Barcelona (ES))

Proceedings

• Bd_OS_tagged_asym.eps
• mcalvo.pdf
• mcalvo.tex
• OS_asym_dstarmunu.eps
• OScalib_jpsik.eps
• OScalib_jpsikstar.eps
• SSK_only.eps
• SSK_OS.eps
• tagschema.eps

Slides Flavour_Tagging_LHCb_PLHC.pdf

47 Electron and photon performance measurements with the ATLAS detector

Speaker: Dimitra Tsionou (Centre National de la Recherche Scientifique (FR))

Paper plhc_tsionou.zip

Slides PLHC2012_f.pdf

48 Status and plans of CMS

Speaker: Joseph Incandela (Univ. of California Santa Barbara (US))

Slides Incandela_PLHC_20120603_F.pptx

49 LHCP-2013 conference

Speaker: Dr Mario Martinez-Perez (Universitat Autònoma de Barcelona (ES))

Slides LHCP2013_BCN.pdf

18:30 Opening Reception

Tuesday, 5 June

2A: Heavy Ion Theory and Experiment

Convener: Dr Christopher Marino (University of Victoria (CA))

50 Heavy ion theory

Speaker: Edmond Iancu (CEA - Centre d'Etudes de Saclay (FR))

Slides iancu_PHLC2012.pdf

51 Heavy ion at RHIC

Speaker: Jamie Nagle (University of Colorado)

Slides nagle_plhc_talk_2012.pptx

52 Heavy ion at LHC

First results from Pb+Pb collisions at a center-of-mass energy of 2.76 TeV per nucleon pair obtained with ALICE, ATLAS and CMS will be presented and discussed in the context of pp collisions at similar energies and of nucleus-nucleus collisions at lower energies.

Speaker: Constantinos Loizides (Lawrence Berkeley National Lab. (US))

Slides loizides_plhc2012_talk_v1.pdf

10:25 Coffee Break

2B: Theory of SM and QCD, Diffractive Physics

Convener: Michel Vetterli (Simon Fraser University)

53 Overview of soft QCD and diffractive physics at LHC

After a short introduction on the importance of the soft and of the diffractive studies in the understanding of minimum bias events, the main results obtained at LHC are discussed. The overview includes identified particle and inclusive measurements, both shedding light on the soft process mechanism. A review of the most recent diffraction results is presented, showing the different approaches used by the LHC experiments, relying on different experimental techniques. The combination of the results obtained by ALICE, ATLAS, CMS, LHCb and TOTEM provides a wide sample of information, covering an unprecedented pseudorapidity range. A detailed comparison between the obtained results is shown, followed by a critical discussion on the still existing discrepancies between the experimental data and the most popular Monte Carlo used at LHC to simulate soft and diffractive physics.

Speaker: Eugenio Scapparone (INFN-Bologna(IT))

Paper

• Csi.eps
• Figure10.eps
• proceeding_plhc2012_es.pdf
• proceeding_plhc2012_es.tex

Slides

• Csi.eps
• Figure10.eps
• PLHC_2012_Scapparone_3.pdf
• PLHC_2012_Scapparone_3.pptx
• proceeding_plhc2012_es.pdf
• proceeding_plhc2012_es.tex

54 Theory of heavy flavour and onia production

Speaker: Prof. Christian Bauer (UC Berkeley)

Slides PLHC_Bauer.pdf

55 Overview of experimental results in heavy flavour and onia production

Speaker: Marco Adinolfi (University of Bristol (GB))

Slides main.pdf

12:45 Lunch

2C: (Parallel) Heavy Ion

Convener: Constantinos Loizides (Lawrence Berkeley National Lab. (US))

56 Theoretical perspectives on the heavy ion LHC program

The strong modification of high transverse momentum particle production in heavy ion collisions ('jet quenching') was one of the major discoveries at RHIC and is currently studied in much greater detail at the LHC. While jet quenching gives access to a variety of phenomena in QCD, the wider kinematic reach of the LHC and the possibility to reconstruct jets in heavy ion collisions challenge theoretical calculations. This talk will be concerned with the interpretation of LHC jet quenching data and recent developments of the theoretical tools.

Speaker: Dr Korinna Christine Zapp (Institute for Particle Physics Phenomenology, Durham University)

Paper plhcproc.pdf plhcproc.tex

Slides vancouver_0612.pdf

57 Particle correlation results from the ALICE experiment at LHC

In-medium modification of jet fragmentation functions in heavy ion collisions is thought to be a direct manifest of the parton energy loss in the medium. Despite the large energy loss signaled by the large imbalance of jet transverse energies in di-jet events[1] and by the suppression of large transverse momentum hadrons [2], it has been found that jet fragmentation functions in Pb-Pb collisions are very similar to the ones measured in p-p collisions[3]. The ALICE experiment has utilized particle correlations to address modification of jet properties in Pb-Pb collisions compared with p-p collisions at the LHC. Furthermore, particle correlations were used to separate particles associated with the jet and those produced with the bulk, as well as to study number and transverse momentum correlation functions in heavy ion collisions. These might help to quantify medium modifications of the parton shower and the response of the surrounding medium. In this talk, we present the latest results on $\Delta\phi$, $\Delta\eta$ and $\Delta\p_{T}$ correlations as well as jet-fragmentation transverse momentum distribution as a function of centrality and transverse momentum. Identified particle ratios of particles associated with the jet and those from the bulk will be discussed. [1] Phys. Rev. Lett. 105 (2010) 252303. [2] Phys. Lett. B696, 30-39 (2011). [3] CMS-PAS-HIN-11-004.

Speaker: Dong Jo Kim (University of Jyvaskyla (FI))

Paper

• plhc2012_proc_djkim_nomacro.tar.gz
• plhc2012_proc_djkim.pdf
• plhc2012_proc_djkim.tar.gz

Slides PLHC2012_DJKIM_final.pdf

58 Strangeness at the new energy frontier: from pp to Pb-Pb with ALICE

We present the measurements of strange and multi-strange hadrons in high energy pp and Pb-Pb collisions at the Large Hadron Collider (LHC) at CERN. The data for these measurements were collected by the ALICE detector in 2010 and 2011. By comparing strangeness data where the Quark-Gluon Plasma (QGP) is not expected to be produced (pp collisions) with data where the energy-density of the collision is sufficient to produce the QGP (central and mid-central Pb-Pb collisions), we are able to investigate the properties of the QGP. We characterise the matter created in the collision by presenting strange and multi-strange particle spectra, yields, and transverse momenta in the context of increasing strangeness number, varying collision energy, and the number of nucleons participating in the collision (N$_{part}$).

Speaker: Dr Betty Abelev (LLNL)

Paper abelev_proceedings.tar.gz plhc2012_abelev.pdf

Slides abelev_pLHC_12_v5.pdf abelev_pLHC_12_v5.pptx

59 Hard probes used in heavy ion collisions to study QCD at extreme energy densities

We present results of the CMS experiment from PbPb collisions at $\sqrt{s_{NN}} = 2.76$ TeV, probing quark and gluon matter at unprecedented values of energy density. The capabilities of the CMS apparatus allows us to investigate various hard probes, using the calorimetry, muon and tracking systems covering a large range in pseudorapidity, complemented by a flexible two-level trigger system. One of the most important early observations was that dijets at high pT are found to be increasingly unbalanced as a function of collision centrality. The overall pT-imbalance can be recovered by including tracks found at low pT and at large angles with respect to the jet axis. Furthermore, the pT-distribution of charged tracks (jet fragments) has been measured using various jet triggers in pp collisions at 7 TeV, and a reference spectrum is constructed to compare to PbPb collisions at 2.76 TeV/nucleon pair. The inclusive production of isolated prompt photons has also been studied in pp and PbPb collisions. CMS is also well equipped to measure muons and dimuons in the high multiplicity environment of heavy ion collisions. Inclusive and differential measurements of the Z and W boson yields show no sign of modification with respect to NLO pQCD calculations. Dimuon decays of the J/psi particle and the Upsilon family are also investigated and results will be presented.

Speaker: Dr Jim Pivarski (Fermi National Accelerator Lab. (US))

Slides pivarski_heavyions_hardprobes_talk_draft4.pdf

60 Heavy flavour production in Pb-Pb collisions at LHC with ALICE

A Large Ion Collider Experiment (ALICE) is the dedicated detector setup to study the high density de-confined state of strongly interacting matter, known as Quark-Gluon Plasma (QGP), which is created in heavy ion collisions at the LHC at CERN. Charm or beauty quarks are among the most interesting and powerful probes to investigate the properties of the QGP, because they are produced on a very short time scale in initial hard scattering processes and thus they experience the whole history of the collision. The investigation of medium modifications of heavy flavour observables will shed light on the properties of the medium and the nature of the parton-medium interactions. ALICE recorded Pb-Pb data at sqrt(s_NN) = 2.76 TeV in 2010 and 2011. This talk will focus on the latest results of open heavy flavour production using hadronic D meson decays at central rapidity, as well as semi-electronic and semi-muonic decays of D and B mesons, at central and forward rapidities, respectively. The corresponding nuclear modification factors, comparisons of the yields in proton-proton and heavy ion collisions, will be presented as a function of transverse momentum and collision centrality. First elliptic flow measurements will be shown as well. Elliptic flow describes the azimuthal momentum space anisotropy of particle emission from non-central heavy ion collisions in the transverse plane. It is sensitive to the early stages of system evolution and thus provides information on thermalization.

Speaker: Yvonne Chiara Pachmayer (Ruprecht-Karls-Universitaet Heidelberg (DE))

proceedings latex source PLHC_proceedings_pachmayer.tar.gz

proceedings pdf file article_plhc_pachmayer.pdf

Slides Pachmayer_plhc2012.pdf

2E: (Parallel) EWK and QCD

Convener: David Strom (University of Oregon (US))

61 Resummation for QCD and EW cross-sections at the LHC

I will discuss recent progress in the all-order resummation of logarithmically enhanced terms in the perturbative expansion of LHC cross sections. At leading logarithmic accuracy, this resummation can be achieved using parton showers. In my talk, I will discuss higher-log resummations performed with effective field theory or diagrammatic methods. The focus will be on recent results for transverse momentum spectra of electroweak bosons (gamma, Z, W and Higgs bosons), and on new precision predictions for the Higgs cross section in the presence of a jet veto.

Speaker: Thomas Becher (University of Bern)

Slides plhc2012_becher.pdf

62 Associated production of W and Z bosons with jets from light and heavy quarks

The associated production of jets and vector bosons allows for stringent tests of perturbative QCD calculations and is sensitive to the possible presence of new physics beyond the Standard Model. The mechanism of production of heavy quarks in association with a W or a Z, in particular, is only partially understood. A measurement of jet production rates in association with W and Z bosons in proton-proton collisions at a 7 TeV center-of-mass energy is presented, using data collected with the CMS detector. The measured jet multiplicity distributions corrected for efficiency and unfolded for detector effects are compared with theoretical predictions. Measurements of the Z+b-tagged jet(s) cross sections and angular correlations are presented. Finally, results for the W+c production rate are also shown.

Speaker: Roberto Castello (Universite Catholique de Louvain (BE))

material proceedings_final.zip

proceeding castello_plhc2012.pdf

Slides castello_PLHC.pdf

63 Physics with electroweak gauge bosons at LHCb

Results of several analyses based on the reconstruction of electroweak gauge bosons at LHCb are reported. The forward coverage of the LHCb detector provides unique sensitivity to various different observables that can be used to test the Standard Model predictions. The results include those on W and Z production and low-mass Drell-Yan production.

Speaker: William James Barter (High Energy Physics Group - Cavendish Laboratory - University of Cambridge)

Proceedings

• barter_plhc2012_proc.pdf
• barter_plhc2012_proc.tex
• CSWA20.eps
• PDFprobes.eps
• Summary.eps

Slides Barter__LHCb_EW_PLHC.pdf

64 W mass measurement from CDF

The mass of the W boson is sensitive to radiative corrections from the top quark and the Higgs boson. We present a new measurement of mW using 2.2/fb of sqrt(s) = 1.96 TeV ppbar collision data collected with the CDF II detector. Utilizing 470126 W → eν candidates and 624708 W → μν candidates, we measure mW = 80387±19 MeV. This is the most precise measurement of mW to date, more precise than all previous measurements of mW combined.

Speaker: Oliver Stelzer-Chilton (TRIUMF (CA))

Paper

• article.pdf
• article.tex
• gfitter.eps
• pscale.eps
• we_eop_fit.eps
• wm_mt_fit.eps

Slides plhc_wmass.pdf

65 W and Z properties and cross sections measured with ATLAS

Precise measurements of W and Z production, differential in p_T and rapidity, are shown. These provide stringent tests of QCD and of lepton universality and are used to extract information on the strange quark content of the proton. In addition, the polarisations of W bosons and of tau leptons produced in W decays are measured.

Speaker: Koichi Nagai (University of Tsukuba (JP))

Proceedings plhc_Koichi_Nagai.pdf PLHC_NAGAI.zip

Slides PLHC-Koichi_NAGAI.pdf

16:10 Coffee Break

2D: (Parallel) Heavy Ion and Soft QCD

Convener: Paul Kuijer (NIKHEF (NL))

66 Results from particle identification in pp collisions measured with ALICE at the LHC

The excellent capabilities of the ALICE experiment for particle identification allow to measure the identified hadron production in a wide range of transverse momentum. For instance, using different techniques, the transverse momentum spectra of charged pions, kaons and protons have been measured from 0.2 GeV/c up to 20 GeV/c. In this talk we present the results on identified particle spectra, strange particle production and particle ratios measured in pp collisions at $\sqrt{s} = 0.9$, 2.76 and 7 TeV. The results are compared with Monte Carlo event generators predictions.

Speaker: Antonio Ortiz Velasquez (Lund University (SE))

Paper article_plhc12_aortizve_11092012.pdf Proceedings_aortiz

Slides aortiz_PLHC2012_v3.pdf

67 Measurements of particle production & energy flow in pp collisions at √s=7 TeV with the LHCb experiment

Due to its unique pseudorapidity coverage and the possibility of extending the measurements to low transverse momenta, LHCb provides important input to the understanding of particle production and energy flow in a kinematical range where QCD models have large uncertainties. The measurements are performed in the pseudorapidity range 2<η<5 which corresponds to the main detector acceptance of the LHCb spectrometer. Measurements of charged & strange particle production and energy flow are compared to predictions given by several Monte Carlo event generators, which model the underlying event activity in different ways.

Speaker: Marianna Fontana (Max-Planck-Gesellschaft (DE))

Paper

• article.pdf
• article.tex
• Fig11a_EF.png
• Fig12a_EF.png
• Fig2a.pdf
• Fig2b.pdf
• Fig4a.pdf
• Fig4b.pdf

Slides PLHC_talk.pdf

68 Recent CMS results on forward and small-x QCD physics

An overview is given of recent CMS results related to small-x QCD physics, dijet production at large rapidity intervals, soft QCD and multi-parton interactions, hard diffraction, central exclusive processes and inelastic pp cross section.

Speaker: Benoit Roland (Universiteit Antwerpen)

proceedings pdf file plhc2012.proceedings.roland.pdf

proceedings source files plhc2012.proceedings.roland.tgz

Slides plhc2012.roland.v3.pdf

69 Heavy quarkonia production in Pb+Pb collisions with ALICE at the LHC

The production of heavy quarkonia (J/psi, psi', Chi_c as well as the Upsilon resonances) has long been considered as a promising tool to study the formation of a Quark Gluon Plasma (QGP) in relativistic heavy ion collisions and has therefore been extensively studied experimentally notably at the SPS (CERN), at RHIC (BNL) and now at the LHC. This production was originally predicted to be suppressed in the presence of a QGP with respect to binary-scaled production rates in pp collisions via a Debye-like color screening mechanism, provided that the temperature (or equivalently the energy density) of the QGP is high enough. However, it has been proposed since then that heavy quarkonia production could also be enhanced due to the coalescence of uncorrelated heavy quark pairs from the hot medium. New measurements performed at the LHC at unprecedentedly high energies should help disentangle these two competing mechanisms. ALICE is the LHC experiment dedicated to the study of heavy ion collisions. It can measure heavy quarkonia production at both mid- (|y| < 0.9) and forward- (2.5 < y < 4) rapidities, down to zero transverse momentum, in both pp and Pb+Pb collisions. Results on heavy quarkonia production in Pb+Pb collisions at a center of mass energy per nucleon-nucleon collision sqrt(s_NN) = 2.76 TeV measured by the ALICE experiment will be presented. They will be compared to state of the art model calculations as well as to other measurements performed at RHIC and at the LHC.

Speaker: Hugo Denis Antonio Pereira Da Costa (Service de Physique Nucleaire)

Slides PLHC-2012_Hugo_Pereira.pdf

2F: (Parallel) Hard QCD and Diffractive

Convener: Fabrizio Ferro (INFN - Genova)

70 Particle production and diffraction in ATLAS

The ATLAS collaboration has measured a wide range of properties of soft particle production. These include forward-backward and azimuthal correlations, azimuthal ordering of hadron production, underlying event properties and their dependence on aspects of the hard scattering process. The inelastic and diffractive cross sections have also been measured, using particle tags and rapidity gaps. Many of these measurements are used to develop and tune models for soft particle production.

Speaker: James Robinson (University College London (UK))

Proceedings ParticleProductionAndDiffraction.121026.tar.gz ParticleProductionAndDiffraction.tar.gz

Slides PLHC.ParticleProductionDiffraction.pdf

71 Onia production at LHCb

Studies of quarkonia production in the forward region provide important tests of NRQCD. During 2010 and 2011 the LHCb experiment has collected a dataset corresponding to an integrated luminosity of 1.0 fb–1 in proton-proton collisions at √s= 7 TeV. We present studies of the production of the J/psi, psi(2S) and chi_c charmonium states as well as bottomonium states. Absolute and relative production rates will be presented and compared to the most recent theoretical predictions available. We also present measurements of double charm production, performed for the first time at a hadron collider.

Speaker: Giacomo Graziani (Universita e INFN (IT))

Paper graziani_plhc2012.pdf

Proceedings graziani_plhc2012_source.tgz

Slides graziani_plhc.pdf

72 Onia production at ATLAS

The production of charmonium product at LHC offers the opportunity to compare different theoretical frameworks. ATLAS is pursuing a program of studies of prompt and non-prompt production of J/psi, psi(2s) and of Y production, for which differential cross sections vs. transverse momentum and rapidity are measured. The subject of Chi states, observed through the radiative transition to J/psi or Y's states, will also be discussed.

Speaker: Takashi Matsushita (Kobe University (JP))

proceedings proceedings.pdf proceedings.tgz

Slides matsushita.pdf

73 J/psi production in p+p collisions with the ALICE experiment

The ALICE experiment at CERN's Large Hadron Collider has studied J/psi production in p+p collisions at 2.76 and 7 TeV center-of-mass energies, as well as in Pb+Pb collisions at sqrt(s_NN) = 2.76 TeV. In this talk, ALICE results on the inclusive J/psi production cross section in p+p collisions at the two energies, measured in the rapidity region |y| < 0.9 for the dielectron decay channel and 2.5 < y < 4 for the dimuon one, will be shown. Moreover, recent results on the non-prompt J/psi fraction extracted at mid-rapidity, on the inclusive J/psi polarization at forward rapidity and on the J/psi production as a function of the charged particle multiplicity for 7 TeV center-of-mass energy collisions will be discussed.

Speaker: Livio Bianchi (Universita degli Studi di Torino)

Paper article.pdf LivioBianchi_ProcPLHC.tar.gz

Slides LivioBianchi_PLHC2012_v3.pdf

Wednesday, 6 June

3A: EWK Theory and Results at LHC and Tevatron

Convener: Richard Keeler (University of Victoria)

74 Electroweak theory

Speaker: Dieter Zeppenfeld (Karlsruhe University and University of Wisconsin)

Slides plhc-zeppenfeld.pdf

75 QCD and B physics at the Tevatron

Speaker: Stephen Wolbers (Fermilab)

Paper

• econfmacros.tex
• Vancouver_wolbers_fig1a.eps
• Vancouver_wolbers_fig1b.eps
• Vancouver_wolbers_fig2.eps
• Vancouver_wolbers_v6.pdf
• Vancouver_wolbers_v6.tex

Slides PLHC_2012_wolbers_1.pdf

76 W and Z physics at the LHC

Speaker: Maria Cepeda Hermida (University of Wisconsin (US))

Slides PLHC_MCepeda_WZPhysics.pdf

77 Diboson physics at the LHC

Speaker: Marc-Andre Pleier (BNL)

Slides Pleier-PLHC2012-v2.pdf

10:45 Coffee Break

3B: Hard QCD

Convener: Colin Gay (University of British Columbia)

78 Hard QCD Theory

Speaker: Zvi Bern (Univ. of California Los Angeles (US))

Slides vancouver12.pdf

79 Inclusive jet and multijet physics

Speaker: Peter Krieger (University of Toronto)

Slides PLHC2012_Pkrieger_Jets_v4a.pdf

80 Direct photon and jet properties

Speaker: Darko Mekterovic (National Central University (TW))

Slides Darko_Mekterovic_PLHC.pdf

81 Status of Monte-Carlo Generators

Speaker: Stefan Hoeche (SLAC / University of Zurich)

Paper

• H-pt_comp_fixsc_runsc.eps
• jetmulti_main.eps
• modmu.eps
• plhc12_hoeche.bbl
• plhc12_hoeche.pdf
• plhc12_hoeche.tex
• tevatron_mjj_exclusive.eps

Slides PLHC12MC.pdf

13:00 Lunch

Excursion

slides Excursion.pdf Excursion.pptx

Thursday, 7 June

4A: B, Charm and Onia - Theory and Experiment

Convener: Isabel Trigger (TRIUMF)

82 B physics theory overview

Speaker: David London (Universite de Montreal)

Paper PLHC_proc.pdf PLHC_proc.tex

Slides PLHC.pdf

83 Mixing and CP violation

Speaker: Olivier Leroy (CPPM)

Paper plhc_OlivierLeroy_proceedings.pdf

Proceedings olivierLeroy_plhc2012_proceedings.tar.gz

Slides plhc_OlivierLeroy.pdf

84 Exotic Onia like spectroscopy

Speaker: Toru Iijima (Nagoya University)

Slides PLHC2012_iijima.final.pptx

85 Rare decays

Speaker: Mitesh Patel (European Organization for Nuclear Research (CERN))

Slides PLHC_June2012.pdf

10:45 Coffee Break

4B: Top Results from LHC and Tevatron

Convener: Reda Tafirout (TRIUMF)

86 Top theory

Speaker: Alexander Dimitrov Mitov (CERN)

Slides AlexanderMitov-top-theory-PLHC-2012.pdf AlexanderMitov-top-theory-PLHC-2012.pptx

87 Top from Tevatron

Speaker: Dr Bernd Stelzer (Simon Fraser University (CA))

Slides top_tevatron_pLHC.pdf

88 Top production

Speaker: Jose Enrique Palencia Cortezon (CERN)

Diapositivas plhc2012_palencia.pdf

89 Top properties

Speaker: Wouter Verkerke (NIKHEF (NL))

Slides plhc-topprop-v4.pptx

13:00 Lunch

4C: (Parallel) B, Charm and Onia I

Convener: Roger Forty (CERN)

90 Heavy flavour results in pp collisions at LHC with ALICE

The ALICE detector provides good performance and specific detector characteristics to study open heavy flavour hadrons and quarkonia, at central (|y| < 0.9) and forward (2.5 < y < 4) rapidity, thanks to its low momentum reach, particle identification capabilities and precise vertexing. Open heavy flavour production is studied using semileptonic decays to electrons and muons and, for open charm states (D^0, D^+, D^* and D_s) at central rapidity, also from exclusive hadronic decay channels. This presentation will cover recent results from measurements in pp collisions at different center of mass energy (at $\sqrt(s)$ = 7 TeV and 2.76 TeV) for all mentioned channels (hadrons, electrons and muons). This set of measurements provides an important test of pQCD calculations and a crucial baseline reference for heavy-ion collisions where the heavy quarks produced early in the collision are used to probe and characterize the strongly-interacting matter produced at high energy density and temperature.

Speaker: Pietro Antonioli (Sezione di Bologna (INFN))

Proceedings Antonioli-PLHC2012-Proceedings.pdf Proceedings (tex+.eps)

Slides Antonioli-PLHC2012.pdf

91 Heavy flavor production at ATLAS

The properties of b-hadrons have been studies in ATLAS, mainly through final states containing muon pairs. This talk will review the analyses completed, focussing on the results published recently (such as the limit on the branching fraction Bs to mu mu), and those currently approaching conclusion on lamda b (observation, mass and lifetime measurement) and Bs->J/psi phi (mixing and CP violation).

Speaker: Daniel Scheirich (University of Michigan (US))

Slides 2012-06-07-Scheirich.pdf

92 Recent results from BESIII

With the world largest J/$\psi$, $\psi^{\prime}$ and $\psi^{\prime\prime}$ data samples collected with BESIII detector at the Beijing Electron Positron Collider(BEPCIII), a series charmonium meson spectroscopy and charmonium decay dynamics have been studies. In this talk, the study of spectroscopy will be introduced, and the new measured parameters of the spin-singlet charmonium states $\eta_{c}$, $\eta^{\prime}_{c}$ and $h_{c}$ will be covered too.

Speaker: Haiping Peng (Univ. of Science & Tech. of China (CN))

Slides PLHC2012-hpeng.pdf

93 New physics hopes considering flavour constraints

The potential for the discovery of flavour symmetric physics models at LHC is discussed. Considering flavour constraints on TeV scale new physics scenarios we motivate considering flavour symmetric extensions of the Standard Model, A systematic flavour symmetric approach to present and future collider anomalies is presented. The anomalous top quark forward backward asymmetry is used as an example to illustrate the potential of such flavour symmetric theories to explain collider anomalies while being consistent with flavour constraints.

Speaker: Michael Robert Trott (CERN)

Slides PLHC2012.pdf

94 Mixing and CPV in the B system

The determination of the CP-violating phase φs in B0s → J/ψφ decays is one of the key goals of the LHCb experiment. Its value is predicted to be very small in the Standard Model but can be significantly enhanced in many models of new physics. We present the world’s best measurement of φs and the first observation of a non-zero ∆Γs based on 1.0 fb−1 of data collected at LHCb during 2011. We also present a measurement of φs using the predominantly CP-odd B0s → J/ψππ decay mode. Additionally we present results on other Bs decay modes, relevant for potential future measurements of φs, such as Bs → φφ and Bs → J/ψK∗0 decays.

Speaker: Sean Benson (University of Edinburgh (GB))

Proceedings PLHCFormat_Mixing.pdf PLHCFormat_Mixing.tex

Slides SB-PLHC2012-Final.pdf

95 CPV in hadronic B decays

The LHCb experiment is a general purpose forward spectrometer operating at the Large Hadron Collider, optimized for the study of B and D hadrons. LHCb collected 1.0 fb-1 of integrated luminosity during 2011 data taking, which provides unprecedented large samples of B hadron decays. These decays offer many complementary measurements of CP violation which probe directly or indirectly the parameters of the CKM matrix. We present here first evidence and observations of CPV in charged, neutral, and strange B mesons decays to hadronic final states.

Speaker: Daniel Johnson (University of Oxford (GB))

Proceedings article.pdf DJohnson_Talk_Proceedings.tgz

Slides 12-06Jun-07_DJohnson_v3.pdf

4E: (Parallel) Top

Convener: Peter Krieger (University of Toronto (CA))

96 New physics signals in top physics

Effective field theories provide a model independent parametrization of the physics beyond the SM if the new degrees of freedom are heavy and complement thus the searches for resonances. In this talk, I will apply this method to the top sector which is expected to play a special role in many BSM scenarios. I will then show the effects of those dimension-six operators on cross-sections and distributions at hadron colliders. Those results together with the present data from the LHC and the Tevatron already constrain the parameter space.

Speaker: Dr Celine Degrande (UIUC/UCL)

Paper

• A_fb_dm.eps
• A_fb_dy.eps
• article.pdf
• article.tex
• Exclusion.eps
• Mttexcl13.eps

Slides TopEFT.pdf

97 Top quark production at ATLAS

We present measurements of the production of top quarks in proton-proton collisions at 7 TeV with the ATLAS detector at the Large Hadron Collider. The cross section of top-quark pair production is measured in the single lepton, dilepton, all hadronic channel and channels with tau leptons. Measurements of single top-quark production in the t-channel is also shown and the single-top quark production in the Wt- and s-channels is explored.

Speaker: Yuta Takahashi (Nagoya University (JP))

Proceedings

• article.tex
• ATL-PHYS-PROC-2012-178.pdf
• econfmacros.tex
• ST.eps
• TT.eps

Slides yuta_20120607_vancouver.pdf

98 Top quark cross section measurements with CMS

Measurement of the top quark pair and single top production cross section at 7TeV are presented, using CMS data collected in 2010 and 2011. The ttbar inclusive cross section are measured in fully hadronic, di-leptonic (including tau lepton) and tau plus jets final states. Differential cross section of the ttbar cross section production and the top quark pairs charge asymmetry are presented as well. The results are combined and confronted with precise theory calculation. The measure of the top pairs invariant mass distribution are used to search for new particle decaying to top pairs

Speaker: Cristina Ferro (Institut Pluridisciplinaire Hubert Curien (FR))

Minutes PLHC_proceeding_CFerro.pdf

Slides

• ChargeAsym.pdf
• Combination.pdf
• e-mu_ptt.pdf
• NNoutput.pdf
• PLHC_2012.pdf
• PLHC_proceeding_CFerro.tex
• Vtb.pdf

99 New top results from D0

The D0 detector at the Fermilab Tevatron proton-antiproton collider has recored almost 10 fb-1 of integrated luminosity at 1.96 TeV. I will present recent precision measurements of various parameters of the top quark sector, which are using a large fraction of this well-understood dataset. In particular, I will highlight the measurement of the forward-backward strong colour charge asymmetry, the world's most precise measurement of the mass of the top quark in dilepton final states, a Tevatron-wide combination of the top quark mass, a novel search for violation of invariance under Lorentz transformations, the first Tevatron-wide combination of the helicity measurements of the W boson in decays of top pairs, the extraction of anomalous couplings, and other measurements.

Speaker: Oleg Brandt (Georg-August-Universitaet Goettingen (DE))

Proceedings 2012_PLHC_TopPropertiesAtD0_OlegBrandt.pdf 2012_PLHC_TopPropertiesAtD0_OlegBrandt.tar.gz

Slides 2012_05_04_PLHC_topD0_OBrandt.pdf

100 Top quark properties at ATLAS

We present results on top quark properties using data collected in 7 TeV LHC proton-proton collisions with the ATLAS detector, including the top-quark charge, mass, the polarization of W bosons, spin correlations and charge asymmetry. A search for flavour changing neutral current processes in top quark production and decay is also presented. Several extensions of the Standard Model predict the presence of new particles that couple to the top quark. We present the result of searches for resonances decaying to top-quark pairs or top-quark partners producing an excess of missing transverse momentum.

Speakers: Andrea Helen Knue (Georg-August-Universitaet Goettingen (DE)), Andrea Knue

Proceedings Proceedings_TopProp.pdf Proceedings_TopProp.tex

Slides TopPropertiesATLAS_AndreaKnue_PLHC_3.pdf

101 Top quark mass and properties measurements with CMS

We present measurements of the top quark mass and other properties, obtained from CMS data collected in 2010-2011 at a centre-of-mass energy of 7 TeV. The mass of the top quark is measured using several methods. We use the lepton+jets and the dilepton decay channels. The results are combined. Top pair production cross section measurements are used to place an indirect constraint on the top quark mass through the predicted dependence of the cross section on the mass. Further results include measurements of top quark charge, the W helicity in top decays and search for anomalous couplings.

Speaker: Michael Maes (Inter-University Institute for High Energies (BE))

Proceedings article.pdf article.tex

Slides presentation.pdf

16:30 Coffee Break

4D: (Parallel) B, Charm and Onia II

Convener: Olivier Leroy (CPPM)

102 Charming new physics

There is experimental evidence for a direct CP asymmetry in singly Cabibbo suppressed $D$ decays, $\Delta A_{CP}$ of order a percent. Naive expectations are that the Standard Model contribution to $\Delta A_{CP}$ is an order of magnitude smaller. We explore the possibility that a major part of the asymmetry comes from new physics. In this context we discuss accommodating this large contribution to CP violation in charm decays in both a minimal model with an extra scalar doublet,previously suggested to explain the large forward-backward asymmetry in $t\bar t$ production at the Tevatron, as well as in supersymmetric flavor models.

Speaker: Yonit Hochberg (Weizmann Institute of Science)

Slides YH_PLHC.pdf

103 Charm mixing and CPV at LHCb

LHCb has collected the world's largest sample of charmed hadrons. The 1.0 fb–1 sample collected in 2011 has been used to search for direct and indirect CP violation in charm, and to measure D0 mixing parameters. Preliminary measurements from several decay modes are presented, with complementary time-dependent and time-integrated analyses.

Speaker: Silvia Borghi (University of Glasgow (GB))

Proceedings

• article.pdf
• article.tex
• figagammaipchi2.eps
• figagammatau.eps
• figdeltaacpdeltam1.eps
• figdeltaacpdeltam2.eps

Slides LHCbCharmMixingCPV_PLHC2012_Borghi.pdf

104 Recent Babar searches for new physics

We present recent BaBar results on two types of new-physics searches. The first type is direct searches for low-mass dark gauge bosons and dark Higgs, motivated by theories developed to explain recent astrophysical anomalies. The second type involves B-meson decays with final states containing neutrinos, where full-event reconstruction is used to measure the 4-momentum of the neutrinos and suppress background. This includes a search for lepton-number violation in B-> K tau l and B-> pi tau l, and searches for flavor-changing neutral-current B decays into final states with neutrinos.

Speaker: Justin Albert (University of Victoria (CA))

Slides PLHC_Babar7Jun12_v2.1.pdf PLHC_Babar7Jun12_v2.1.ppt

105 Search for New Physics with rare decays at LHCb

Rare lepton decays of the B(s), D and K mesons and lepton flavor violating decays are sensitive probes of New Physics (NP). In particular, the search for the decays B(s)->μ+μ- provides information on the presence of new (pseudo-)scalar particles, while the angular analysis of decays such as B->K*μ+μ- provides information on possible new vector-axial contributions. The isospin asymmetry of B->K(*)μ+μ- events adds useful information on the structure of NP scenarios and other b->sμ+μ- transitions provide additional information. Similarly, exclusive radiative decays such as Bs->φγ provide valuable information of NP scenarios through the measurement of the photon polarization.

Speaker: Cosme Adrover Pacheco (CPPM - Universite d'Aix - Marseille II (FR))

Figures

• afb_result.pdf
• isospin_k_result.pdf
• isospin_kstar_result.pdf
• xpoint.pdf

Proceedings article.pdf article.tex

Slides adrover_PLHC_RD.pdf

106 B physics and Quarkonium results from CMS

Using large data samples of di-muon events, CMS has performed detailed measurements in the field of quarkonium production. Differential cross-sections of J/psi, psi(2S) and Y(nS) states in pT and rapidity will be presented, separated in prompt and non-prompt contributions for the charmonium case: experimental results are compared with recent predictions in the context of NLO nonrelativistic QCD and the FONLL scheme. Studies of P-wave charmonia and bottomonia (chi_c, chi_b), using the decay mode (J/psi, Y) + gamma where the photon converts in an e+e- pair inside the detector, will be also discussed.

Speaker: Roberto Covarelli (University of Rochester (US))

Proceedings article.pdf article.tex

Proceedings - figures

• chic_ratio.pdf
• xib0_Zoom.pdf
• XS_all_p_sg_psi2s_teor_paper.pdf

Slides PLHC12_Bphys.pdf PLHC12_Bphys.pptx

4F: (Parallel) EWK and QCD

Convener: Dieter Zeppenfeld (KIT - Karlsruhe Institute of Technology (DE))

107 Multi Vector Boson Production via Gluon Fusion at Hadron Colliders

At the LHC, the processes with several particles in the final states occur routinely. These processes provide a new domain to test the standard model. Some of these processes can be discovery/confirmation channel for beyond the standard model scenarios also. Therefore, it is important to compute the contribution of the standard model to such multiparticle events. Furthermore, due to large gluon luminosity at the LHC, the gluon initiated processes can be quit important. We consider the production of multi vector bosons via gluon fusion. In particular we consider the processes g g -> \gamma Z g and g g -> \gamma \gamma Z. These processes get contribution from the pentagon type diagrams also. We calculate these pentagon type (and box type) diagram contributions to the cross-section and distributions of these processes at hadron colliders. To do this calculation, we use Oldenborgh-Vermaseren techniques to reduce tensor-loop integrals to the scalar-loop integrals. We apply numerous checks to our calculations including cancellation of ultaviolate and infrared singularities as well as gauge invariance. Final numerical computation requires the use of PVM to do parallel calculation on a cluster of computers. Our results for the cross-sections suggest that these processes can be observed after a few years of the running of LHC.

Speaker: Prof. Pankaj Agrawal (Institute of Physics, Bhubaneswar, India)

Proceedings agrawal-plhc.tar plhc-divector.pdf

Slides vanc2012.pdf

108 Cross sections for Wgamma and Zgamma Production in 7Tev pp collisions

We present the measurement of Wgamma and Zgamma production cross sections using data corresponding to the full 2010 and 2011 periods of the LHC run. For charged lepton decay modes of W and Z bosons the total cross sections are measured for photon transverse energy greater than 15 GeV. We also present the first measurement of Zgamma production cross section using the nunugamma final state for photon transverse energy greater than 145 GeV. The results are also interpreted in terms of limits of anomalous trilinear gauge couplings.

Speaker: Yurii Maravin (Kansas State University (US))

Slides Vgamma_at_CMS.pdf

109 ATLAS diboson measurements

ATLAS has measured diboson production processes involving ZZ, WW, WZ, Wgamma and Zgamma. Visible cross sections are measured for channels involving leptons and neutrinos, and differentil distributions are presented. In the ZZ to 2l2nu and WW to lnulnu channels, jet vetos are applied. Total cross ections are derived, and limits are set on anomalous triple-gauge couplings.

Speaker: Shu Li (CPPM(FR)/USTC(CN))

Proceeding ATL-PHYS-PROC-2012-151.pdf proceeding_ShuLi.tar.gz

Slides DiBosonPLHC_ShuLi_Jun7.pdf

110 New QCD results from DZero

Speaker: Darren Price (Indiana University)

Slides dprice_QCD.pdf

111 Measurement of the Drell-Yan Cross Section with the CMS detector at the LHC

We present a measurement of the Drell Yan differential cross-section dsigma/dm, and the double differential cross section d^2sigma/dmdY in pp collisions at 7 TeV using a dataset corresponding to an integrated luminosity of 5 fb−1 recorded at the LHC with the CMS detector. The complete cross-section measurement is reported for both the di-muon and di-electron channels. The cross-section is measured in the di-lepton invariant mass range 15 - 1500 GeV/c2 and the results are compared to theoretical predictions. The cross-section values are quoted with and without acceptance and final state radiation corrections.

Speaker: Norbert Neumeister (Purdue University)

Paper proceedings.pdf

Proceedings Proceedings.zip

Slides PLHC.pdf

112 ATLAS measurements of photons, jets and subjets

Comprehensive measurements of inclusive and dijet cross sections are presented, spanning the dijet mass range from 70 GeV to 4 TeV. Inclusive photons and diphotons have also been measured over a wide range of mass and pT. These measurements constitute precision tests of QCD in a new energy regime, and show sensitivity to the parton densities in the proton. In addition, charged particles, subjets and jet shapes have been measured, to investigate jet fragmentation and to study new variables developed to reduce sensitivity to soft QCD and pileup, and to improve the identification of boosted heavy particles decaying to hadrons.

Speaker: Stephen Gibson (CERN)

Proceedings plhc2012_gibson.pdf proceedings_gibson.zip

Slides 120607pLHC_Gibson.pdf

Friday, 8 June

5A: Higgs and Alternatives, Theory and Results

Convener: Bernd Stelzer (Simon Fraser University)

113 Higgs and alternatives - theory

This talk will review the theoretical possibilities for the dynamics underlying electroweak symmetry breaking, in light of the 2011 LHC results and expectations for the future.

Speaker: Prof. Heather Logan (Carleton U.)

Slides higgs.pdf

114 Higgs from Tevatron

Speaker: Prof. Bob Hirosky (University of Virginia)

Slides Hirosky_PLHC2012.pdf

115 Higgs in ATLAS

Speaker: Scott Snyder (Brookhaven National Laboratory (US))

proceedings latex source plhc12-snyder.tar.gz

proceedings PDF file plhc12-snyder.pdf

Slides 2012-06-08-plhc.pdf

116 Higgs searches in CMS

Speaker: Chiara Ilaria Rovelli (CERN)

Paper proceedingsChiara.pdf proceedingsRovelli.tar.gz

Slides rovelli.pdf

10:50 Coffee Break

5B: SUSY & BSM, Theory and Results

Convener: Bob Kowalewski (University of Victoria)

117 SUSY and BSM theory

Speaker: Csaba Csaki (Cornell University)

Slides PLHC2012Csaki.pdf

118 Electroweak and hints of new physics at the Tevatron

Speaker: Dr Andrew Warren Askew (Florida State University (US))

Paper AskewProc.tar.gz

Slides Askew_PLHC_6_2012.pdf

119 SUSY and BSM searches in CMS

Speaker: Frederic Ronga (Eidgenoessische Tech. Hochschule Zuerich (CH))

Slides fronga-PLHC.pdf

120 ATLAS SUSY and BSM

Speaker: Till Eifert (SLAC National Accelerator Laboratory (US))

Proceedings article.pdf proceedings_eifert.tgz

Slides PLHC2012_SUSY_BSM_ATLAS.pdf

13:00 Lunch

5C: (Parallel) Higgs I

Convener: Dr Mario Martinez-Perez (Universitat Autònoma de Barcelona (ES))

121 *A* Higgs or *The* Higgs?

Accurate determination of Higgs properties at the LHC can help to identify the particle's origins in theory space and will provide crucial consistency checks for any bigger picture into which such a state might fit. We can already make progress in this effort using the searches and data provided for the SM-like Higgs, employing straightforward techniques to construct exclusions in very generic parameter spaces. Bottom-up approaches like the ones discussed here will be crucial for assessing the precise role of a scalar field discovered at the LHC, and can reveal whether or not the consistency of our theories will require the intervention of other new physics at accessible scales.

Speaker: Jamison Galloway (Rome La Sapienza)

Paper PLHC.zip

Slides PLHC_Galloway.pdf

122 Combined search for the Standard Model Higgs boson using up to 4.9 fb-1 of pp collision data at sqrt(s) = 7 TeV with the ATLAS detector at the LHC

A combination of Standard Model Higgs boson searches with the ATLAS experiment, in a dataset corresponding to an integrated luminosity of up to 4.9 fb-1 of pp collisions collected at sqrt(s) = 7 TeV at the LHC in 2011 is presented. Upper limits on the cross-section times branching ratio are derived.

Speaker: Justin Kien Keung (University of Toronto (CA))

Slides 20120608_Higgs2011CombinationATLAS_jkeung.pdf

123 Search for the SM Higgs in the to two photon and two Z to four lepton decay channels at CMS

Results are presented on the search for the Standard Model Higgs decaying into two photons or into two Z bosons, with each Z boson decaying into a pair of charged leptons. The full data sample of 4.7/fb of pp collisions collected in 2011 with the CMS experiment at the LHC have been analysed. The search results are translated into 95% exclusion limits for the Higgs boson, as function of the Higgs mass.

Speaker: Nicholas Wardle (Imperial College Sci., Tech. & Med. (GB))

Proceedings

• econfmacros.tex
• nwardle_plhc2012_hgghzzsearchesatcms_proceedings.pdf
• nwardle_plhc2012_hgghzzsearchesatcms_proceedings.tex
• sqr_grid_acls_combp_zoom.eps
• sqr_grid_pvala_combp_zoom.eps

Slides nw_hggzz_plhc2012_8Jun2012.pdf

124 CDF Higgs searches

The latest results from the CDF Collaboration on searches for the Standard Model Higgs Boson using up to 10 fb-1 of proton-anti-proton collisions at 1.96 TeV center-of-mass energy. Recent improvements in b-quark identification, online event selection, and background rejection have significantly increased the sensitivity across a wide range of Higgs masses (100 - 200 GeV/c^2). These improved techniques will be discussed along with their application to the current searches. The expected sensitivity at mH = 125 (165) GeV/c^2 is 1.39 (0.67) times the SM cross section respectively with a 95% exclusion region for Higgs masses between 148.8 < m_H < 175.2 GeV/c2 and m_H < 96.9 GeV/c2.

Speaker: Michael Kirby (Northwestern University)

latex

• cdf27febsmlimits100.eps
• econfmacros.tex
• flow.eps
• kirby_plhc2012_proceedings.tex
• sort.eps

Paper Proceedings

Slides Kirby_CDF_Higgs_PLHC2012.pdf

125 Searches for a light Higgs boson at ATLAS

The experimental results of the Standard Model Higgs searches with the ATLAS experiment, in a dataset corresponding to an integrated luminosity of up to 4.9 fb-1 of pp collisions collected at sqrt(s) = 7 TeV at the LHC, are presented. Several channels contributing to the sensitivity in the most challenging low-mass region are discussed. The exclusion limits at the 95% confidence level are given as a function of the Higgs boson mass. The observed small excess of events above the background expectation is addressed.

Speaker: Tatsuya Masubuchi (University of Tokyo (JP))

latex PROCsource.tar.gz

Proceedings ATL-PHYS-PROC-2012-191.pdf

Slides PLHC_2012_v2.pdf

126 Search for non-SM Higgs at CMS

Results are presented on the search for the non-Standard Model Higgs production and decays, including neutral Higgs to a pair of tau leptons, charged Higgs studies and the production of double charged Higgs bosons decaying into a pair of like single charged leptons. Also a search for a low mass $a_0$ decaying into a muon pair is reported. The full data sample of 4.7 fb$^{-1}$ of pp collisions collected in 2011 with the CMS experiment at the LHC have been analysed. The search results are translated into 95% exclusion limits for the Higgs boson, as a function of the Higgs mass.

Speaker: Evan Klose Friis (University of Wisconsin (US))

Slides friis_bsm_higgs.pdf

5E: (Parallel) SUSY

Convener: Till Eifert (SLAC National Accelerator Laboratory (US))

127 SUSY confronts LHC data

The current searches at the LHC have set strong bounds on the masses of gluinos and the squarks of the first and second generation. At the same time, the hints of a Higgs boson at 125 GeV imply some degree of fine-tuning from radiative corrections to the lightest Higgs mass. Moreover, the rate into photons seems to be enhanced with respect to the SM, while the ZZ channel is reduced (albeit the SM is still compatible at the 2-sigma level). In this talk I will review how the previous issues can be addressed. If the stop is about a couple-hundred GeV, the SUSY still remains as a natural solution to the hierarchy problem. I will also show how the MSSM can accommodate a 125 GeV Higgs and also how extensions of the MSSM can alleviate the fine-tuning on the Higgs mass. I will also discuss recent literature, showing how both in the MSSM and its extensions one can find suitable ways to accommodate the measured Higgs rates into photons and Z bosons.

Speaker: José Francisco Zurita (University of Zurich)

Paper

• econfmacros.tex
• pphgagazztb20.pdf
• pphgagazztb2.pdf
• tb20_channels.pdf
• tb2_channels.pdf
• Zurita.pdf
• Zurita.tex

Slides Zurita_PLHC.pdf

128 Searches for SUSY in hadronic final states at CMS

We present results of searches for SUSY production at CMS in events containing hadronic jets and missing energy, with or without isolated photons or heavy flavor. Various discriminants based on the event kinematics are employed to suppress standard-model backgrounds. The results are interpreted in the context of the Constrained Minimal Supersymmetric Standard Model, and of a number of "simplified models".

Speaker: Riccardo Bellan (Univ. of California Santa Barbara (US))

Proceedings ProceedingsBellanPLHC12.pdf

Proceedings src ProceedingsBellanPLHC12.tar.gz

Slides PLHC_RBellan.pdf

129 Inclusive searches for supersymmetric signatures with the ATLAS detector

The talk summarises recent results on inclusive searches for supersymmetric squarks and gluinos in events containing jets, missing transverse momentum with or without leptons or photons. Also presented are results on searches for exotic supersymmetric signatures involving long-lived massive particles. The searches use the full data sample (5 fb-1) recorded in 2011 at sqrt(s) = 7 TeV centre-of-mass energy by the ATLAS experiment at the LHC.

Speaker: Enrique Kajomovitz Must (Israel Institute of Technology (IL))

proceedings

• article.pdf
• article.tex
• chargino_limit.png
• GMSB_searches.png
• limits_26_jets.png
• simplified_69.png

Slides PLHC12-InclusiveSusy-f1.pdf

130 Physics objects from CMS: muons

The performance of muon reconstruction and identification in CMS has been studied on data collected in pp collisions at √s = 7 TeV at the LHC. We present measurements of muon reconstruction and trigger efficiencies, fake rates, and momentum scale and resolution, and discuss methods developed to differentiate prompt isolated muons from non-prompt, cosmic, and beam-halo muons.

Speaker: Clara Jorda Lope (Universidad de Cantabria (ES))

Paper

• article.pdf
• article.tex
• GLB_hlt15tight_eta_linear.eps
• GLB_hlt15tight_ptbin25_log.eps
• ResolutionWithSIDRAandSIDRASIMandTheoryErrors.eps
• TMOST_barrel.eps
• TMOST_endcaps.eps

Slides PLHC2012_MuonsCMS_Jorda_v1.pdf

131 Searches for SUSY in final states with leptons at CMS

We present results of searches for SUSY production at CMS in events with lepton signatures. These include final states with single isolated leptons, Z bosons decaying to lepton pairs, non-resonant same- and opposite-sign lepton pairs, and three or more isolated leptons. The results are used to exclude previously unexplored regions of the supersymmetric parameter space assuming R-parity conservation with the lightest supersymmetric particle being either a neutralino or gravitino.

Speaker: Benjamin Stieger (ETH Zurich)

Proceedings Proceedings_PLHC12_Stieger.pdf Proceedings_PLHC12_Stieger_Source.zip

Slides PLHC_LeptSusyCMS_Stieger.pdf

132 Search for supersymmetric gauginos and third generation squarks with the ATLAS detector

Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the Higgs and electroweak gauge bosons and third generation quarks with masses not too far from those of their Standard Model counterparts. Gauginos and scalar top or bottom quarks with masses less than a few hundred GeV 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 production of third generation squarks via decay of a gluino can also be significant if the mass of the gluino does not exceed the TeV scale. The talk presents results from searches for stop, sbottom and gaugino production using the full data sample (5 fb-1) recorded in 2011 at sqrt(s) = 7 TeV centre-of-mass energy by the ATLAS experiment at the LHC.

Speaker: Josh Mcfayden (University of Sheffield (GB))

Slides PLHC_susy3genGaug_mcfayden_v4.pdf

16:30 Coffee Break

5D: (Parallel) Higgs II

Convener: Scott Snyder (Brookhaven National Laboratory (US))

133 Light stau phenomenology and the 125 GeV Higgs γγ rate

Recently, an excess of events consistent with a Higgs boson with mass of about 125 GeV was reported by the CMS and ATLAS LHC experiments. The mass is consistent with the values that may be obtained in minimal supersymmetric extensions of the Standard Model (SM), with third generation squarks masses at the TeV scale with large mixing. The apparently enhanced photon production rate and suppressed ZZ production rate associated with this potential Higgs may be the result of light third generation sleptons in the presence of large mixing. Such large mixing and large coupling of the staus to the SM-Higgs boson may be obtained for large values of tanβ and moderate values of the Higgsino mass parameter, μ. We study the phenomenological properties of this scenario, including precision electroweak data, Dark Matter, the muon anomalous magnetic moment and the evolution of the soft supersymmetry breaking parameters to high energies. We also analyze the possible collider signatures of third generation sleptons and the prospects of finding evidence of their production at the 8 TeV and the 14 TeV LHC.

Speaker: Nausheen Shah

Slides Vancuover.pdf

134 Combined results of SM Higgs searches at CMS

Results are presented on the search for the Standard Model Higgs combining all decay channels. The combination has been updated with the latest results released for the 2012 winter conferences, including additional channels with respect to the results released end of December 2011. The full data sample of 4.7 pb-1 of pp collisions collected in 2011 with the CMS experiment at the LHC have been analysed. An excess with a local p-value of around 3 sigma is seen at low mass, which reduces to less than 2 sigma significance when the look elsewhere effect is taken into account. The search results are translated into 95% exclusion limits for the Higgs boson, as function of the Higgs mass, excluding a SM Higgs in the region of 127 GeV to 600 GeV.

Speaker: Artur Kalinowski (University of Warsaw (PL))

Proceedings Kalinowski_PLHC2012.pdf Proceedings_Kalinowski.tar.gz

Slides PLHC2012_Kalinowski.pdf

135 Searches for a heavy Higgs boson at ATLAS

The experimental results of the search for the Standard Model Higgs boson at the Large Hadron Collider (LHC) running at a centre-of-mass energy of 7 TeV are reported, based on a total integrated luminosity of up to 4.9 fb-1 collected by the ATLAS detector in 2011. Several channels contributing to the sensitivity in the high-mass region above mH-200 GeV are discussed. Upper limits are derived on the production cross section as a function of the Higgs boson mass. A wide range of Higgs boson mass hypotheses is excluded at a 95% confidence level.

Speaker: Alex Christopher Martyniuk (University of Victoria (CA))

Proceedings PLHC-ATLASHighMassHiggs.pdf PLHC-HighMassHiggs.zip

Slides PLHC2012-ATLAS_HighMassHiggs.pdf

136 Tracking, vertexing and b-tagging performance at ATLAS

The talk summarises recent studies of the b-tagging performance in ATLAS data. Measurements of the efficiency to tag a jet originating from a b-quark are presented, as well as measurements of the rate with which c-jets or light-flavour jets are mistakenly tagged by the ATLAS b-tagging algorithms. These studies are important inputs to all physics analyses making use of b-tagging.

Speaker: Sara Kristina Strandberg (Stockholm University (SE))

Proceedings plhc_2012_strandberg.pdf plhc_2012_strandberg.tar

Slides strandberg_plhc2012.pdf

137 Search for the SM Higgs in bb, tau tau, WW and ZZ decay channels at CMS

Results are presented on the search for the Standard Model Higgs decaying into two b-quarks, two tau leptons, two W bosons, with each boson decaying into a charged lepton and a neutrino, and two Z bosons, with one of the Z bosons decaying into charged leptons, and the second one into jets, neutrinos or tau leptons. The full data sample of 4.7 pb-1 of pp collisions collected in 2011 with the CMS experiment at the LHC have been analysed. The search results are translated into 95% exclusion limits for the Higgs boson, as function of the Higgs mass.

Speaker: Lorenzo Bianchini (Ecole Polytechnique (FR))

Proceedings article.pdf article.tex

Slides higgsSearches_v2.pdf

138 Searches for beyond-Standard Model Higgs boson

The discovery of a neutral Higgs boson with large decay branching fraction to tau and muon pairs, as well as the discovery of a charged Higgs boson would represent a strong evidence of new physics beyond the Standard Model. The experimental results of the searches for the Higgs bosons beyond the Standard Model with the ATLAS detector are reported. The searches are based on an integrated luminosity of up to 4.9 fb-1 of proton-proton collision data recorded at the Large Hadron Collider (LHC) at a centre-of-mass energy of 7 TeV. Exclusion limits on production cross-sections are given as function of the Higgs boson mass and of minimal supersymmetric model parameters.

Speaker: Ohad Silbert (Weizmann Institute of Science (IL))

Slides pLHC_beyondSMH.pdf

5F: (Parallel) BSM

Convener: Prof. Heather Logan (Carleton U.)

139 Non-standard signals of new physics

In this talk I will discuss several new physics scenarios that will not be uncovered with SUSY-motivated searches (jets + MET, etc.). These signals include: top partners, multi-jet resonances, and W/Z/gamma + jet(s) resonances.

Speaker: Adam Martin (Fermilab)

Slides amartin_plhc.pdf

140 Searches for Exotics physics states decaying to leptonic final states

We present searches for new particles decaying to leptonic final states using data collected in 7 TeV LHC proton-proton collisions with the ATLAS detector. Our studies include dileptons, diphotons, excited leptons, leptons + missing transverse energy, dibosons or multileptons in same and opposite electric charge. These studies test wide set of predictions for extensions to Standard Model, including exotics long lived particles that decay far from the interaction point.

Speaker: Roger Moore (University of Alberta (CA))

Slides 2012-06-PLHC2012.pdf

141 New physics with jets in the final state at CMS

We present searches for new physics at CMS using final states that contain mainly jets. Topics include di-jet resonance searches, searches for extra dimensions, as well as resonances decaying to pairs of top quarks that appear as merged jets in the detector.

Speaker: Paolo Rumerio (University of Alabama (US))

Paper proceedings_rumerio_PLHC2012__CMS_CR_2012_263.pdf

Slides NewPhysicsWithJetsAtCMS.odp NewPhysicsWithJetsAtCMS.pdf

src proceedings_rumerio.tar

142 Lepto-quark and di-quark at the LHC

New physics at the LHC may appear as the discovery of lepto-quark gauge bosons, or di-quark resonances, as those can be produced strongly via gluon gluon fusion and giving distinctive signals in the final states. In this talk, I will discuss theoretical motivation and models giving rise these particles at the TeV scale. Lepto-quark in the TeV scale evade the existing strong bound from the flavor changing processes by unifying quarks and leptons in higher dimensions, and the breaking the gauge symmetry to the Standard Model via compactification. This type of models gives additional new quarks and leptons, and a possible dark matter candidate which can be explored at the LHC. The models of di-quarks give rise to new physics contribution in the t t as well as single top production which can be explored at the LHC. This talk will review this field, and also discuss our recent work (arXiv1201.5616 [hep-ph], submitted to Phys. Rev. D, and arXiv1201.2917 [hep-ph], to appear in Phys. Rev. D).

Speaker: Prof. Satyanarayan Nandi (Oklahoma State University)

Slides plhc2012_talk_nandi.pdf

143 Searches for Exotics physics states in jets and boosted objects final states

We present searches for new particles decaying to jets and boosted objects final states using data collected in 7 TeV LHC proton-proton collisions with the ATLAS detector. We present studies of states like diljets, photons + jets, dibosons, ttbar resonances and 4th generation particles decaying hadronically. These studies demonstrate the usage of novel techniques for reconstruction of boosted objects and test wide set of predictions for Exotics extensions to Standard Model.

Speaker: Ludovica Aperio Bella (Centre National de la Recherche Scientifique (FR))

Diapositivas LAB_PLHC2012_boosted.pdf

Paper LAB_exotic_PLHC2012.pdf

Proceedings

• fig_boosted3.eps
• fig_dijet1.eps
• fig_dijet2.eps
• fig_Semiboosted.eps
• LAB_exotic_PLHC2012.tex

144 New physics with final state leptons at CMS

We present searches for new physics with leptons in the final state. This includes dilepton resonances, new physics with three or more lepton final states, as well as heavy top-like quarks decaying to bottom quarks. We also present searches for heavy bosons decaying to leptonic final states.

Speaker: Arnd Meyer (Rheinisch-Westfaelische Tech. Hoch. (DE))

Slides plhc_6_2012.pdf

Conference Dinner: <br>(Museum open for viewing at 19:00)

slides Dinner.pdf Dinner.pptx

Saturday, 9 June

6A: Poster Winners, Cosmo/Astro/DM @ LHC, HI @ RHIC and LHC

Convener: Guenakh Mitselmakher (University of Florida)

145 Seach for supersymmetric particles using final states with one lepton, jets and missing transverse momentum with ATLAS detector

Speaker: Yuichi Sasaki (University of Tokyo (JP))

Slides slides_ysasaki.pdf

146 Supersymmetry in Final States with s Single Lepton, B-jets and Missing Transverse Energy in proton-proton collisions at 7 TeV

Speaker: Niklas Andreas Pietsch (Hamburg University (DE))

Slides poster.pdf poster_talk.pdf

147 Search for charged Higgs bosons decaying via H+ --> tau nu in 7 TeV pp collisions with the ATLAS detector

Speaker: Anna Katharina Kopp (Albert-Ludwigs-Universitaet Freiburg (DE))

Slides Posterslides_AnnaKopp.pdf

148 The LHC and the rest of the Universe

Speaker: Alvaro De Rujula (Consejo Superior de Investigaciones Cientificas (CSIC) (ES))

Movies movie-1.mov movie.mov

Slides

• VancouverTalk.key
• VancouverTalk.pdf
• VancouverTalk.ppt

149 Long term perspectives for HI with RHIC and LHC

Speaker: John William Harris (Yale University (US))

Slides Harris_-_Future_of_HI_at_RHIC_and_LHC_v2.pdf

10:30 Coffee Break

6B: Experimental Summary, Theory Summary and Vision, Farewell

Convener: Robert McPherson (University of Victoria)

150 Experimental conference summary

Speaker: Karl Jakobs (Albert-Ludwigs-Universitaet Freiburg (DE))

Slides PLHC_12_Summary.pdf PLHC_12_Summary.pptx

151 Theoretical summary, vision for future

Speaker: Gian Giudice (CERN)

Paper

• deadoraliveG2012.pdf
• giudice.pdf
• giudice.tex
• mhSplit2.pdf
• SMht.pdf

Slides vancouver2.pdf

152 Farewell

Speaker: Robert Mcpherson (University of Victoria (CA))

12:50 Lunch and Departure