Recent results of the CMS experiment QFTHEP2015 The 22 th International Workshop on High Energy Physics and Quantum Field Theory, Samara (Russian Federation) Dr. Bora Akgün – Rice University (on behalf of CMS Collaboration)

Outline Recent Results of the CMS Experiment - 25 June CMS - Data Collection Selected Results Vector Bosons – arXiv: , arXiv: Quarkonia – PRL 114 (2015) , arXiv: Rare Decays – Nature 522 (2015) 68 Top Physics – arXiv: SUSY – arXiv: Exotica – arXiv: What to expect from Run2 and beyond Summary

CMS Detector Recent Results of the CMS Experiment - 25 June 20153

Data Collection Recent Results of the CMS Experiment - 25 June Results presented in this talk have been produced with LHC Run-1 data collected by CMS experiment CMS Public Results twiki

CMS Standard Model Summary Plot Recent Results of the CMS Experiment - 25 June Great agreement btw theory and measurements

Vector Bosons Recent Results of the CMS Experiment - 25 June W and Z can be measured very accurately through their leptonic decays, photon energies precisely measured in the electromagnetic calorimeter Z and photons used for calibration of jets, Z used as a candle to determine lepton efficiencies Vector boson plus jets are major backgrounds in beyond standard model searches and excellent testing ground for QCD NLO predictions Diboson processes (ZZ and γγ) are major SM backgrounds for Higgs measurements WZ and ZZ w/ Z  νν major contribution to backgrounds in searches w/ large missing transverse energy (e.g. SUSY)

Z+jets / Photon+jets Recent Results of the CMS Experiment - 25 June Z+jets Photon+jets V+jets are major backgrounds in beyond standard model searches and excellent testing ground for QCD NLO predictions arXiv: n jet ≥1

Z+jets / Photon+jets Recent Results of the CMS Experiment - 25 June The ratio of Z + jets to γ + jets Both simulations reproduce the shape of the ratio better than the individual distributions in all selections arXiv: n jet ≥1 n jet ≥2

Production cross-section for ZZ  llνν Recent Results of the CMS Experiment - 25 June ZZ  llνν production cross section measured Using a profile likelihood fit to the reduced-E T miss Main backgrounds DY, WZ, WW,W+jets,top σ(pp  ZZ) = (stat) (syst)±0.2(lumi)pb at 7 TeV σ(pp  ZZ) = (stat) (syst)±0.3(lumi)pb at 8 TeV Theory calculations w/ NLO QCD and NLO EW σ(pp  ZZ) = at 7 TeV σ(pp  ZZ) = at 8 TeV arXiv:

Production cross-section for ZZ  llνν Recent Results of the CMS Experiment - 25 June ZZγ and ZZZ expected to be null at the tree level Enhancement in ZZ production rate compared to SM indicate the existence of anomalous boson couplings arXiv: No observation of new physics  stringent limits on the relevant Anomalous Triple Gauge Coupling (ATGC) parameters

Charmonium spectrum Recent Results of the CMS Experiment - 25 June cross sections and polarizations cross section ratio observation, cross section observation with > 5σ

Prompt ψ(ns) cross-sections Recent Results of the CMS Experiment - 25 June Yields are corrected for efficiency and acceptance on an event-by- event basis PRL 114 (2015)

Prompt ψ(ns) cross-sections Recent Results of the CMS Experiment - 25 June Yields are corrected for efficiency and acceptance on an event-by- event basis Four polarization scenarios are considered P T reach is extended compared to previous measurements FKLSW band is obtained in a fit to previous data w/ essentially P T < 30 GeV and extrapolated to higher P T values PRL 114 (2015) un-polarized scenario

Bottomonium spectrum Recent Results of the CMS Experiment - 25 June cross sections and polarizations cross section ratio

ϒ(ns) differential cross-sections Recent Results of the CMS Experiment - 25 June Acceptance calculated w/ polarization values measured by CMS (PRL 110 (2013) ) P T reach is extended compared to previous measurements arXiv: ϒ(2S), ϒ(3S) scaled by 0.1, 0.01, respectively NRQCD

ϒ(ns) production ratios Recent Results of the CMS Experiment - 25 June arXiv: Exponential fit – 10 < P T < 20 GeV Power-law fit – P T >20 GeV Change in ratios occur at the same P T range in which dσ/dP T also changes behavior

B S 0  μ + μ - and B 0  μ + μ - Recent Results of the CMS Experiment - 25 June SM predicts small branching fractions for B S 0   + μ - and B 0   + μ - Direct flavor-changing neutral currents not possible in SM, theories beyond SM predict larger branching fractions Nature 522 (2015) 68

First observation - B S 0  μ + μ - (CMS & LHCb) Recent Results of the CMS Experiment - 25 June Weighted distribution of dimoun mass-spectrum, superimposed in a combined fit First observation of B S 0   + μ - (6.2σ) and evidence for B 0   + μ - (3.2σ) Nature 522 (2015) 68

Combined result - B S 0  μ + μ - (CMS & LHCb) Recent Results of the CMS Experiment - 25 June Likelihood in B S 0   + μ - vs B 0   + μ - branching ratio plane BR: B S 0   + μ - = * ( * SM) BR: B 0   + μ - = * ( * SM) Nature 522 (2015) 68

Top mass measurements Recent Results of the CMS Experiment - 25 June The most massive particle known to date Very short lifetime shorter than hadronization timescale The only elementary high mass particle that has color EWK, QCD and flavor physics Combined top mass using all CMS Run-1 data ±0.10(stat.) ±0.65(syst.) GeV

ttbar production cross- section at 7/8TeV Recent Results of the CMS Experiment - 25 June ttbar production cross-section measured w/ different channels at 7 and 8 TeV ttbar is a major background for many processes

ttbar differential measurements Recent Results of the CMS Experiment - 25 June MC generators predict harder dilepton mass and lepton P T spectrum than observed in data Powheg+Herwig6 provide a satisfactory agreement 8 TeV results are input for future MC tuning arXiv:

SUSY searches Recent Results of the CMS Experiment - 25 June SUSY, popular BSM theories Solves the hierarchy problem Provides a suitable dark matter candidate SUSY corrections allow for high energy unification of strong and electroweak couplings Searches involve typically the presence of large missing transverse energy and multijets

SUSY search w/ two leptons, jets and E T miss Recent Results of the CMS Experiment - 25 June arXiv: The invariant mass distribution of the two-lepton system can exhibit an excess that increases with the di-lepton mass, followed by a sharp decrease, if the two leptons originate from the decay of a neutral particle decayed from a bottom squark-antisquark production 1.Mass difference btw Χ 2 0 and Χ 1 0 fixed to 70 GeV 2.Mass of the slepton chosen to lie halfway btw the masses of Χ 2 0 and Χ 1 0 Lepton pair from the decay of an o-shell Z boson from gluino pair production

SUSY search w/ two leptons, jets and E T miss Recent Results of the CMS Experiment - 25 June M ll > 20 GeV Njets ≥ 2 arXiv: Low mass significance: 2.6σ No evidence for a statistically significant signal

SUSY search w/ two leptons, jets and E T miss : setting limits Recent Results of the CMS Experiment - 25 June arXiv:

Exotica: Narrow high-mass resonance decaying to Z and H Recent Results of the CMS Experiment - 25 June arXiv: A search for a highly massive ( ≥ 0.8TeV) and narrow resonance decaying to Z and H bosons that decay in turn to merged dijet and ττ final states τ decaying leptonically and hadronically Advanced reconstruction techniques in boosted topology Main backgrounds (simulated in MC) Z+jets/W+jets Ttbar, single-t ZZ,WW,QCD Main source of uncertainty: limited MC statistics for signal efficiencies and background estimation

Exotica: Narrow high-mass resonance decaying to Z and H Recent Results of the CMS Experiment - 25 June arXiv: From a combination of all possible decay modes of the τ leptons, production cross sections in [ fb] depending on the resonance mass [ TeV], are excluded at a 95% CL

What have we been doing lately? Recent Results of the CMS Experiment - 25 June Finishing analyses w/ 2012 data Many results and publications (≥400), more to come.. Long Shutdown (LS) – 1: Fixes and upgrades to CMS detector Pixel detector taken out, misbehaving channels (~5%) fixed and installed back to CMS w/ an additional part - pilot system w/ upgrade electronics and readout Muon detectors New stations (CSC/RPC) to complete redundancy, new electronics for triggering Narrower beampipe Preparation for upgrade pixel detector in 2017 Re-commissioning of the detector for Run-2

Detector Improvements for Run 2 Recent Results of the CMS Experiment - 25 June Muons Completion of forward detector 4 th layer in ME RPCs to |η|=4 Tracker at C Pixel Pilot System New Beam pipe

13 TeV Collisons Recent Results of the CMS Experiment - 25 June June 3 rd : First collisions at the new center of mass energy

LHC plan for 2015 Recent Results of the CMS Experiment - 25 June

What to expect in Run-2? Recent Results of the CMS Experiment - 25 June EW & Quarkonia Improve on precision w/ higher statistics Top Increase mass precisions w/ better jet energy scale systematic uncertainties Use boosted reconstruction techniques to perform differential cross-section measurements Improve precision on ttZ, ttW, ttH cross-sections Higgs Look for deviations from SM w/ higher precision SUSY Discovery? ??

Summary Recent Results of the CMS Experiment - 25 June Only a small portion of results out of the rich long list of measurements performed by CMS In general predictions provide a good description of data CMS is ready for Run-2 data taking (already started) Sophisticated reconstruction techniques, analysis tools, analysis methodologies and interpretation approaches have been developed and matured during the previous years Exciting times ahead of us