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B Physics and Quarkonia at CMS

B Physics and Quarkonia at CMS. ICNFP 2014 Kolymbari , Crete 6 August 2014. Claudia-Elisabeth Wulz CMS Collaboration Institute of High Energy Physics, Vienna. Overview. Selected recent results:

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B Physics and Quarkonia at CMS

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  1. B Physics and Quarkonia at CMS ICNFP 2014 Kolymbari, Crete 6 August 2014 Claudia-Elisabeth Wulz CMS Collaboration Institute of High Energy Physics, Vienna

  2. Overview • Selected recent results: • CP-violating phase ϕsand decay width difference DGs of Bs with Bs -> J/y f(1020) • Production cross sections • J/y and y(2S) prompt double-differential • Polarization • J/y, y(2S),ϒ(1S), ϒ(2S),ϒ(3S) CMS PAS BPH-13-012 CMS PAS BPH-14-001 PLB 727 (2013) 381 PRL 110 (2013) 081802 All CMS public B physics results: https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsBPH

  3. Bs-> J/ψ(μ+μ-) Φ(K+K-) Decay channel: Bs -> J/y(μ+μ-) Φ(K+K-) Bs-Bs mixing -> time-dependent, flavour-tagged analysis Data: √s = 8 TeV, Lint = 20 fb-1, 49000 reconstructed Bsdecays Weak phase from interference of direct decays and decays from mixing, and decay width difference of light and heavy Bs mass eigenstates: _ fD + new physics? J/y Φ Bs -fD fM _ Bs + new physics?

  4. Angular analysis • Time-dependent, angular analysis to disentangle CP-odd and CP-even final states: • Measure decay angles Θ(θT,φT,ψT) and proper decay length ct of Bs Signal model φ a parameter set: ΔΓs, ϕs, cτ, IA0I2, IAIII2, IATI2, IASI2, δ0, δII, δT, δS bi and di depend on ϕs Extended maximum likelihood fit with signal model used to extract parameters. PRD 87 (2013) 112010 - LHCb

  5. Event selection and Bs reconstruction • Trigger: displaced J/y, optimized for b hadrons • 2 muons with pT(μ) > 4 GeV, pT(μμ) > 6.9 GeV • Mass window for μμ: [2.9,3.3] GeV • Common decay vertex, Lxy/σxy> 3, dca3D < 0.5 cm • c2 vertex fit probability > 15% • Offline selection: • pT(μ+), pT(μ-) > 4 GeV, IημI< 2.1 • Dimuons from common vertex from Kalman fit • J/ymass constraint: Imμ+μ-– MJ/yI< 150 MeV • pT(K+),pT(K-) > 0.7 GeV • ϕmass constraint: ImK+K-– MΦI < 10 MeV • Bs (μμKK) reconstruction by combined kinematic and vertex fit: • c2 vertex fit probability > 2% • Mass within [5.24, 5.49] GeV • Selected primary vertex: closest to Bs(minimal angle between flight direction and momentum of Bs) CMS PAS BPH-13-012

  6. Background, efficiencies, resolution • Main background: non-prompt J/yfrom b hadrons • Lifetime and angular resolution and efficiencies: from simulation • Angular efficiency: modeled by 3D-function of decay angles • Angular resolution: not in nominal fit, but included as systematic uncertainty • Proper decay time efficiency: not in nominal fit, flat in fitting range [0.02,0.3] cm, variations included as systematic uncertainty • Proper decay time resolution (70 fs or 21 μm): per-event uncertainty from Bs vertex finding + scale factor κ(cτ) taking into account the difference with respect to the resolution CMS PAS BPH-13-012

  7. Flavor tagging Flavor of Bs at production time determined by tagging e or μ on opposite side and considering its charge Tagging performance optimized by maximizing tagging power Ptag= εtag(1-2ω)2 separately for e and μ(ω … mistag fraction) εtag measured from data, using self-tagging channel B+ -> J/yK+, and checked by simulation with B+ -> J/yK+ and Bs-> J/y K*0 events Combined average tagging performance: ω= (32.3 ± 0.3)%, εtag= (7.67 ± 0.04)%, Ptag= (0.97 ± 0.3)% CMS PAS BPH-13-012

  8. Systematic uncertainties CMS PAS BPH-13-012

  9. Fit results Multi-dimensional maximumlikelihood fit appliedwithtaggedsignalmodel, Gaussianconstraint on Δmsto PDG value Fit range: Bs mass in [5.24, 5.49] GeV ct in [0.02, 0.3] cm CMS PAS BPH-13-012

  10. Results on Φs,ΔΓs CMS PAS BPH-13-012 ϕs = - 0.03 ± 0.11 (stat.) ± 0.03 (syst.) rad ΔΓs= 0.096 ± 0.014 (stat.) ± 0.007 (syst.) ps-1

  11. Quarkoniacross sections and polarization Heavy quarkoniainterestingtounderstandhadronformation. S-wavevectorquarkoniaformedfrom heavy qqpairscreatedas: colorsinglet (CS) 3S1[1]oroneof 3 coloroctets (CO)1S0[8], 3S1[8], 3PJ[8] -> similarcrosssectionshapes, but different polarizations. Experimental situation on polarization not clearuptonow, crosssectionsonlymeasured in lowerpTrange. _

  12. Quarkonium polarization Polarizationof JPC = 1––quarkoniumstatesmeasuredthrough angular distributionofdileptonsfrom J/yorϒdecay z Quarkonium rest frame PRD 16 (1977) 2219 PRD 19 (1979) 207 Quantization axis z ϑ ℓ + production plane φ y x Transverse JZ = ±1 Longitudinal JZ = 0 EPJC C69 (2010) 657 Frame-invariant:

  13. Selection of prompt charmonia Prompt charmoniadistinguishedfrom B-hadrondecaysthroughμμ pseudo-proper decaylengthl(Lxy ... most probable transversedecaylength) Yield: extendedunbinnedmaximum-likelihood fit to 2D M-ldistribution l =Lxy.mψ(nS)/pT EPJC 71(2011) 1575

  14. Single μ efficiencies, correlations and acceptance Single muonefficiencies: tag&probemethod ρ: trigger-inducedmuon pair correlations Acceptance: polarization-dependent Unpolarizedscenariousedforcrosssectionmeasurements CMS-PAS-BPH-14-001

  15. J/ψand ψ(2S) production CMS PAS BPH-14-001 ICNFP, Aug. 2014

  16. ψ(nS) and ϒ(nS) polarizations PLB 727(2013) 381 J/yandy(2s) polarizations, 7 TeV ϒ(1s), ϒ(2s), ϒ(3s) polarizations, 7 TeV PRL 110 (2013) 081802 ϒ(1S) ψ(2S) J/ψ ϒ(2S) ϒ(3S) - Full angular decaydistributionsmeasured in 3 framesand frame-independently - Continuumbackgroundfromsidebands in the invariant mass distribution - Non-prompt charmoniumcontributionsremovedusingdecaylength

  17. J/ψand ψ(2S) polarization

  18. J/ψand ψ(2S) polarization • No strong polarization • No strong pTdependence • Similar in otherframesandforotherpolarizationparameters • NLO NRQCD predictions (nofeed-down for J/y) do not agreewithdata

  19. ϒ(nS) polarization • No strong polarization • No strong pTorydependence PRL 110 (2013) 081802 PRL 108 (2012) 151802

  20. ψ(2S), ϒ(3S) production versus NRQCD JHEP 02 (2012) 011 PRD 87 (2013) 052004 CMS-PAS-BPH-12-006 PLB 727 (2013) 381 PRL 110 (2013) 081802 PLB 736 (2014) 98 • cb(3P) feed-down to (3S) neglected • Unpolarized1S0[8]component dominates quarkonium production

  21. Conclusions on new CMS results • CMS has measured with very good precision CP-violating phase fs and decay width difference DGs of Bs with Bs-> J/y(μμ)f(KK), in agreement with standard model (√s = 8 TeV, Lint = 20 fb-1). • CMS has measured J/y and y(2S) prompt double-differential cross sections up to O(100 GeV) in pT(√s = 7 TeV, Lint = 4.9 fb-1). • CMS has measured polarization of JPC = 1––quarkoniumstatesthroughangular distributionofdileptonsfrom J/yorϒdecays(√s = 7 TeV, Lint = 4.9 fb-1). No strong polarizationisseen.Unpolarized1S0[8] component dominates quarkoniumproduction. • CMS is preparing to take new B physics data at √s = 13 TeV in 2015. ICNFP, Aug. 2014

  22. BACKUP

  23. Charmonium spectrum ψ‘ J/ψ directly produced directly produced cc _ ψ’ non-prompt (b-hadrons) non-prompt (b-hadrons) χc2 χc1 1--

  24. Bottomonium spectrum χbJ(3P) directly produced directly produced directly produced (1S) (2S) (3S) (3S) (2S,3S) 1-- χbj(1P) χbj(2P) χbj(2P) 1-- _ bb 35-45% χbj(3P) χbj(3P) χbj(3P)

  25. Pseudo-proper decay length l = Lxy· mψ(nS)/pT Eur.Phys.J.C71:1575,2011

  26. Hadron formation and NRQCD NRQCD is an effective field theory that factorizes quarkonium production in two steps: production of the initial quark-antiquark pair (perturbative QCD) hadronizationof the quark pair into a bound quarkoniumstate (non-perturbative QCD) NRQCD predicts the existence of intermediate color-octet (CO) states in nature, that subsequently evolve into physical color-singlet (CS) quarkonia by non-perturbative emission of soft gluons. quarkonium ( ) = 2S+1LJ[C], C = 1,8 antired Quantum numbers of the heavy quark pair S, L, J = spin, orbital and total ang. momentum antiblue _ possibly coloredqq pair ofany possible 2S+1LJ quantum numbers 2) non-perturbative evolution to the observed bound state Quantum numbers change! Cartoon by P. Faccioli red green 1) perturbative phase

  27. B Physics and Quarkonia at CMS ICNFP 2014 Kolymbari, Crete 6 August 2014 Claudia-Elisabeth Wulz CMS Collaboration Institute of High Energy Physics, Vienna

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