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View on Recent Results from LHCb

View on Recent Results from LHCb. Niels Tuning on behalf of the LHCb collaboration. Disclaimer. In the rest of the talk I will assume the speed of light to be constant and that particles cannot travel faster than c. “Box” diagram: Δ B=2. s. b. s. b. b. μ. s. μ.

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View on Recent Results from LHCb

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  1. View on Recent Results from LHCb Niels Tuning on behalf of the LHCb collaboration Niels Tuning - View on Recent Results of LHCb - APPS2011

  2. Disclaimer • In the rest of the talk I will assume the speed of light to be constant and that particles cannot travel faster than c. Niels Tuning - View on Recent Results of LHCb - APPS2011

  3. “Box” diagram: ΔB=2 s b s b b μ s μ Search for New Physics with B-physics Search for new particles or forces via their virtual loop contributions in B decays • 2) Rare Decays: • Search for enhanced BR’s or decay • distributions that deviate from SM • Examples: • B0 →K*μμ • B0s →μμ • 1) CP Violation: • Search for CP asymmetries incom- • patible with SM fits. • Study of couplings of New Physics • Examples: • Bs0 →J/ψφ “Penguin” diagram: ΔB=1 Niels Tuning - View on Recent Results of LHCb - APPS2011

  4. Reminder: Mixing and Rare Decays for discoveries s d d b b μ d μ B0 mixing pointed to the top quark: K0→μμpointed to the charm quark: GIM, Phys.Rev.D2,1285,1970 ARGUS Coll, Phys.Lett.B192:245,1987 … … … Niels Tuning - View on Recent Results of LHCb - APPS2011

  5. Menu: LHCb “Superstars” “Box” diagram: ΔB=2 s b s b b μ s μ • B0s → J/ψφ • B0 → K*μμ • B0s → μμ “Penguin” diagram: ΔB=1 • Other LHCb talks: • today: W. Hulsbergenin BSM session • tomorrow N. Serra in discrete symmetries session Niels Tuning - View on Recent Results of LHCb - APPS2011

  6. Menu: LHCb “Superstars” B0s→ J/ψφ • B0s → J/ψφ • B0 → K*μμ • B0s → μμ B0→K*μμ B0s→μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  7. Commonality: “FCNC” γ b s • B0s → J/ψφ • B0 → K*μμ • B0s → μμ B0s→ J/ψφ B0→K*μμ B0s→μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  8. Commonality: “FCNC” γ b W t s • B0s → J/ψφ • B0 → K*μμ • B0s → μμ B0s→ J/ψφ B0→K*μμ B0s→μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  9. Commonality: “FCNC” b W W t s • B0s → J/ψφ • B0 → K*μμ • B0s → μμ B0s→ J/ψφ B0→K*μμ B0s→μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  10. Sensitive to NP: appetizer B0s→ J/ψφ • B0s → J/ψφ • B0 → K*μμ • B0s → μμ (4/3)AFB B0→K*μμ B0s→μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  11. Status before Summer CDF, Conf Note 10206 B0s→ J/ψφ φs • B0s → J/ψφ • Decreased 3σ→ 1σ • B0 → K*μμ • Hint for deviaton • B0s → μμ • SM p-value 1.9% BABAR: PRL 102, 091803 (2009) CDF: Note 10047 (2010) Belle: PRL 103, 171801 (2009) B0→K*μμ CDF, arXiv:1107.2304 B0s→μμ mB Niels Tuning - View on Recent Results of LHCb - APPS2011

  12. The LHCb Detector 23 sep 2010 19:49:24 Run 79646 Event 143858637 Niels Tuning - View on Recent Results of LHCb - APPS2011

  13. The LHCb Detector B0→K*μμ B0s→μμ PID B0→K*(Kπ)μμ Lifetime, B0s → J/ψφ RICH1 T MAGNET TT VELO MUON CALO RICH2 Interaction Point Suppress background, σ(MB) B0 →K*μμ B0s→μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  14. LHC and LHCb performance • LHC and LHCb show excellent performance • Analyzed 330 pb-1 for Summer conferences • 1011 bb-pairs produced! x 4.7 ~0.3 fb-1 for Summer • Optimal use of LHC beam: • “Lumilevelling” at 3.5 1032 • (Design was 2.0 1032 !) • Max. luminosity for entire fill • With maximum detector occupancy Niels Tuning - View on Recent Results of LHCb - APPS2011

  15. Menu: LHCb “Superstars” “Box” diagram: ΔB=2 s b s b b μ s μ • B0s → J/ψφ • B0 → K*μμ • B0s → μμ “Penguin” diagram: ΔB=1 Niels Tuning - View on Recent Results of LHCb - APPS2011

  16. B0s → J/ψφ Niels Tuning - View on Recent Results of LHCb - APPS2011

  17. B0s → J/ψφ: Introduction B0s→J/ψφ • Interfering decay amplitudes: • B0s→J/ψφ • B0s → B0s→ J/ψφ t >0.3 ps N = 8276 ± 94 σ ~ 7 MeV L ~ 337 pb-1 NB: Despite hadronic environment very clean signals! eiφs A.S.Dighe, I.Dunietz, R.Fleischer Eur.Phys.J.C6:647-662,1999 Niels Tuning - View on Recent Results of LHCb - APPS2011

  18. B0s → J/ψφ: Analysis • Angular analysis • B0s → J/ψφ: • Pseudo-scalar →2 vectors • CP ~ (-1)L • Flavour tagging b: use this b to check if other b oscillated Niels Tuning - View on Recent Results of LHCb - APPS2011

  19. B0s → J/ψφ: Analysis • Angular analysis • B0s → J/ψφ: • Pseudo-scalar →2 vectors • CP ~ (-1)L • Flavour tagging tagging B Niels Tuning - View on Recent Results of LHCb - APPS2011

  20. Intermezzo: Tagging with Bs0→Ds-π+ • Need “flavour specific decay” • N(Bs0→Ds-π+) = 9189 ± 147 • Bs oscillates fast • Bs0→Ds-π+ orBs0→B s0→ Ds+π- • Need good proper time resolution • ε: tagging efficiency • ω : wrong tag fraction • ε(1-2ω)2: tagging power LHCb-CONF-2011-050 Amix = (N(B→B)-N(B→B))/ (N(B→B)+N(B→B)) Amix = (1-2ω) cosΔmst Niels Tuning - View on Recent Results of LHCb - APPS2011

  21. Intermezzo: Tagging with Bs0→Ds-π+ • Need “flavour specific decay” • N(Bs0→Ds-π+) = 9189 ± 147 • Bs oscillates fast • Bs0→Ds-π+ orBs0→B s0→ Ds+π- • Need good proper time resolution • ε: tagging efficiency • ω : wrong tag fraction • ε(1-2ω)2: tagging power LHCb-CONF-2011-050 LHCb-CONF-2011-050 1-2ω Amix = (N(B→B)-N(B→B))/ (N(B→B)+N(B→B)) Amix = (1-2ω) cosΔmst Bs0→Ds-π+ Niels Tuning - View on Recent Results of LHCb - APPS2011

  22. B0s → J/ψφ: Analysis LHCb-CONF-2011-049 • Angular analysis • B0s → J/ψφ: • Pseudo-scalar →2 vectors • CP ~ (-1)L • Flavour tagging • ω = 36% • εD2 = 3.1±0.8% • PDG: Δms=17.77 ±0.120 ps-1 • LHCb: Δms=17.725±0.041±0.025 ps-1 LHCb-PAPER-2011-021-001 CP + CP - B0s→ J/ψφ LHCb-CONF-2011-050 LHCb-PAPER-2011-010-002 (preliminary) Bs0→Ds-π+ Niels Tuning - View on Recent Results of LHCb - APPS2011

  23. B0s → J/ψφ: Angular Analysis Niels Tuning - View on Recent Results of LHCb - APPS2011

  24. B0s → J/ψφ: Results LHCb-CONF-2011-049 ΔΓs • Most precise value of φs! φs=0.13 ± 0.18(stat) ± 0.07(sys) rad • Consistent with SM: φs=-0.03 ΔΓs=0.123 ± 0.029(stat) ± 0.008(sys) ps-1 = 1 σ = SM φs (preliminary) CDF:Γs=0.076 ± 0.059(stat) ± 0.006(sys) ps-1 D0:Γs=0.19 ± 0.07 (stat) ± 0.015(sys) ps-1 Niels Tuning - View on Recent Results of LHCb - APPS2011

  25. B0s → J/ψφ: Comparison Niels Tuning - View on Recent Results of LHCb - APPS2011

  26. Sub-Summary • B0s → J/ψφ • B0 → K*μμ • B0s → μμ • Most precise measurement of φs • φs=0.13 ± 0.18(stat) ± 0.07(sys) rad • Combine with B0s → J/ψf0 • See talk from W. Hulsbergen today (preliminary) Niels Tuning - View on Recent Results of LHCb - APPS2011

  27. B0 → K*μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  28. B0→K*μμ: Motivation A.Ali, Th.Mannel, T.Morozumi Phys.Lett. B273 (1991) 505-512 • Hadronic uncertainties largely cancel in angular asymmetries • Forward-backward asymmetry AFB easiest μ+ θl K* μ- Example: (4/3)AFB W.Altmannshofer et al., JHEP 0901:019,2009 Niels Tuning - View on Recent Results of LHCb - APPS2011

  29. B0→K*μμ: Motivation A.Ali, Th.Mannel, T.Morozumi Phys.Lett. B273 (1991) 505-512 • Hadronic uncertainties largely cancel in angular asymmetries • Forward-backward asymmetry AFB easiest Example: (4/3)AFB W.Altmannshofer et al., JHEP 0901:019,2009 Niels Tuning - View on Recent Results of LHCb - APPS2011

  30. B0→K*μμ: Status Belle, 657M BB PRL 103, 171801 (2009) • AFB measured at B-factories and CDF • All opposite sign for AFB? • Hint of deviation? Babar, 465M BB PRD 79, 031102 (2009) SM CDF 6.8 fb-1 arXiv:1108.0695 NB: Size of C7 constrained by BR(B0→K*γ) but not the sign. SM Niels Tuning - View on Recent Results of LHCb - APPS2011

  31. B0→K*μμ: at LHCb ψ' • Reject J/ψandψ’ resonances • Veto peaking backgrounds • Select with boosted decision tree • E.g. B, J/ψ, K*vtx, FD, IP, … • N(B0→K*μμ) = 302 ± 20 • Babar: 60 • Belle: 247 • CDF: 164 J/ψ B0 LHCb-CONF-2011-038 N = 302 ± 20 L ~ 309 pb-1 Niels Tuning - View on Recent Results of LHCb - APPS2011

  32. B0→K*μμ: at LHCb ψ' • Reject J/ψandψ’ resonances • Veto peaking backgrounds • Select with boosted decision tree • E.g. B, J/ψ, K*vtx, FD, IP, … • N(B0→K*μμ) = 302 ± 20 • Babar: 60 • Belle: 247 • CDF: 164 J/ψ B0 LHCb-CONF-2011-038 1<q2<6 GeV2 N = 70 ± 10 L ~ 309 pb-1 N = 302 ± 20 L ~ 309 pb-1 Niels Tuning - View on Recent Results of LHCb - APPS2011

  33. B0→K*J/ψ: Asymmetry μ+ BaBar, PRD 79, 031102 (2009) • Validate analysis on B0→K*J/ψ: • FL = 0.556±0.015 (Babar: 0.556±0.009±0.010) • AFB = -0.006±0.008 (preliminary) θl K* μ- NB: q2 = mJ/2 = 9.6 GeV2 signal sideband LHCb-CONF-2011-038 Niels Tuning - View on Recent Results of LHCb - APPS2011

  34. B0→K*μμ: Asymmetry Ch.Bobeth,G.Hiller,D.van Dyk JHEP 1107:067,2011 • Validate analysis on B0→K*J/ψ: • FL = 0.556±0.015 (Babar: 0.556±0.009±0.010) • AFB = -0.006±0.008 • Measure AFB and FL in bins of q2 • Event-by-event acceptance correction LHCb-CONF-2011-038 m2μμ= Niels Tuning - View on Recent Results of LHCb - APPS2011

  35. B0→K*μμ: Comparison J/ψ ψ' LHCb LHCb-CONF-2011-038 Belle, PRL 103, 171801 (2009) Babar, PRD 79, 031102 (2009) CDF, PRL 106, (2011) Niels Tuning - View on Recent Results of LHCb - APPS2011

  36. B0→K*μμ: Asymmetry Ch.Bobeth,G.Hiller,D.van Dyk JHEP 1107:067,2011 • Still limited statistics • Good agreement with SM Example: LHCb-CONF-2011-038 (4/3)AFB W.Altmannshofer et al., JHEP 0901:019,2009 Niels Tuning - View on Recent Results of LHCb - APPS2011

  37. B0→K*μμ: Comparison Niels Tuning - View on Recent Results of LHCb - APPS2011

  38. Sub-Summary • B0s → J/ψφ • B0 → K*μμ • B0s → μμ • Most precise measurement of AFB • Zero-crossing point is next • Still limited statistical precision • 3x more data on tape • More angular observables available U.Egede at al JHEP 0811:032,2008 Niels Tuning - View on Recent Results of LHCb - APPS2011

  39. B0s → μμ Niels Tuning - View on Recent Results of LHCb - APPS2011

  40. B0s→μμ: Motivation • Branching Ratio very sensitive to NP models • BR strongly enhanced in MSSM at large tanβ:  tan6/mA4 • Example: 10x higher BR for tan=50(20), mH+=800(200) GeV A.Buras, G.Isidori, P.Paradisi Phys.Lett.B694:402-409,2011 Allowed parameter space from fit in constrained MSSM: 1-CL tanβ=50 mH+=200 GeV Mt1=500 GeV, Mt2=850 GeV 5σ discov. CMS @30/60 fb-1: H,A → τ+τ− 10x SM 10x SM → tan  → MH+ (GeV) A.Buras et al., Nucl.Phys.B659:3,2003 O.Buchmueller et al. Eur.Phys.J.C64:391-415,2009 Niels Tuning - View on Recent Results of LHCb - APPS2011 (Direct limits at CMS: Gennai et al. Eur.Phys.J.C52:383-395,2007)

  41. B0s→μμ: Motivation • Branching Ratio very sensitive to NP models • BR strongly enhanced in MSSM at large tanβ:  tan6/mA4 • Example: 10x higher BR for tan=50(20), mH+=800(200) GeV A.Buras, G.Isidori, P.Paradisi Phys.Lett.B694:402-409,2011 Allowed parameter space from fit in non-univ Higgs mass (NUHM): 1-CL tanβ=50 mH+=200 GeV Mt1=500 GeV, Mt2=850 GeV 10x SM 10x SM → tan  → MH+ (GeV) A.Buras et al., Nucl.Phys.B659:3,2003 O.Buchmueller et al. Eur.Phys.J.C64:391-415,2009 Niels Tuning - View on Recent Results of LHCb - APPS2011

  42. B0s→μμ: Motivation • Branching Ratio very sensitive to NP models • BR strongly enhanced in MSSM at large tanβ:  tan6/mA4 • Example: 10x higher BR for tan=50(20), mH+=800(200) GeV A.Buras, G.Isidori, P.Paradisi Phys.Lett.B694:402-409,2011 1-CL tanβ=50 mH+=200 GeV 2x10-8 1x10-8 Mt1=500 GeV, Mt2=850 GeV 5x10-9 10x SM 10x SM SM-like → tan  → MH+ (GeV) A.Buras et al., Nucl.Phys.B659:3,2003 Curves obtained through SuperIso, (eg. F.Mahmoudi, arXiv:0906.0369) Niels Tuning - View on Recent Results of LHCb - APPS2011

  43. B0s→μμ: at LHCb • Analysis based on • Mass • Kinematic / geometrical • (eg. τB, IPB, IPSμ, DOCA, isolation, …) • Compare observed to expectation Candidate B0s→μμ event, 14 June 2011 Niels Tuning - View on Recent Results of LHCb - APPS2011

  44. B0s→μμ: mass LHCb preliminary 2011 √s = 7 TeV L ~ 150 pb-1 B0s→μμ? 5.4 Niels Tuning - View on Recent Results of LHCb - APPS2011

  45. B0s→μμ: mass LHCb preliminary 2011 √s = 7 TeV L ~ 150 pb-1 B0s→μμ? 5.4 Niels Tuning - View on Recent Results of LHCb - APPS2011

  46. B0s→μμ: mass σ(M) = 16 MeV σ(M) = 40 MeV J/ψ(1S) (1S,2S,3S) Niels Tuning - View on Recent Results of LHCb - APPS2011

  47. B0s→μμ: mass Linear dependence checked on MC σ(M)mB = 24 MeV (confirmed with B→ππ decays) J/ψ(1S) σ(m) (MeV) (1S,2S,3S) mμμ (MeV) Niels Tuning - View on Recent Results of LHCb - APPS2011

  48. B0s→μμ: topological μ • Kinematic / geometrical: • B lifetime • IP μ, IPSμ, pT,μ, min(pT,μ) • DOCA 2 muons • μ and B isolation • Combine the info (“BDT”) μ Signal (B0(s)→hh) Background (mass sidebands) Niels Tuning - View on Recent Results of LHCb - APPS2011

  49. B0s→μμ: event yields • Analysis based on 300 pb-1 • Highest BDT-bin similar to CMS: • Observe 2 events, expect: • ~0.7 background • ~0.8 SM Less background (preliminary) Expected B0s→μμ yield (SM) Niels Tuning - View on Recent Results of LHCb - APPS2011

  50. B0s→μμ: event yields • Analysis based on 300 pb-1 • Around Bs mass ±20 MeV: • Observe 11 events, expect: • ~9.5 background • ~1.2 SM Less background (preliminary) Expected B0s→μμ yield (SM) Niels Tuning - View on Recent Results of LHCb - APPS2011

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