Flavour Physics at hadron machines

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1 Flavour Physics at hadron machines KIAS Phenomenology Workshop Seoul, Korea, November 2011 T. Nakada EPFL-LPHE Lausanne, Switzerland

2 B physics, started with hadron machine First discovery of b-quark by a fixed target experiment ϒ(1S, 2S, 3S) b-b bound states μ + μ T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

3 Early b physics with hadron machines B d -B d + B s -B s oscillations with di-muon sample pp collider at CERN s = 546, 630 GeV UA1 PLB 1987 UA1 PLB 1991 Prob(B B) Prob(B B) Prob(B B) T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

4 Not much success from fix target fixed target contribution had been marginal: i.e. σ bb vs s PLB 1998 WA92 Experiment Simply was too low cross sections T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

5 Success with the colliders Tevatron started in 1988, showed its potential already during Run I, thanks to large σ bb largest number of reconstructed B ± J/ψK ± at that time T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

6 Real breakthrough with Run II data Vertex detectors are essential for b physics CDF and D0 measurements on B s0 -B 0 s oscillation frequency CDF PRL 2006 Exclusive reconstruction essential for a good σ τ T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

7 Some highlights from Tevatron CP violation in B s J/ψφ b s B s0 -B 0 s oscillations W t, c, u W s b b W c s c φ s J/ψφ : phase difference In the SM 2λ 2 η T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

8 Some highlights from Tevatron CP violation in B s J/ψφ b s B s0 -B 0 s oscillations W t, c, u W s b b W c s c φ s J/ψφ : phase difference In the SM 2λ 2 η + New Physics phase T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

9 Some highlights from Tevatron CP violation in B B b s B s0 -B 0 s oscillations W t, c, u W s b b s c, u s b D0: PRD 2011 Pr(B B) Pr(B B) Pr(B B) + Pr(B B) =Im(Γ 12 /M 12 ) In the SM (B d ) (B s ) T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

10 Some highlights from Tevatron Muon A FS in B 0 K *0 μ + μ angular distribution of the muon pairs, resulting from the interference of the two diagrams. T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

11 Some highlights from Tevatron Muon A FS in B 0 K *0 μ + μ BELLE (PRL2009) BABAR (PRD2009) New Physics? Standard model T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

12 Some highlights from Tevatron Muon A FS in B 0 K *0 μ + μ BELLE (PRL2009) BABAR (PRD2009) CDF (PRL2011) New Physics still? Standard model T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

13 LHC Two general purpose experiments (ATLAS and CMS), one dedicated b-experiment (LHCb), and one dedicated heavy ion experiment (ALICE) + small experiments T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

14 LHC pp at s =7 TeV from 2010 pp run in 2011 finished L dt: ATLAS/CMS 5 fb 1 and LHCb 1fb 1 data T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

15 LHC pp at s =7 TeV from 2010 pp run in 2011 finished L dt: ATLAS/CMS 5 fb 1 and LHCb 1fb 1 data ATLAS/CMS running at maximum luminosities LHCb running at constant luminosities T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

16 LHC pp at s =7 TeV from 2010 pp run in 2011 finished L dt: ATLAS/CMS 5 fb 1 and LHCb 1fb 1 data ATLAS/CMS running at maximum luminosities LHCb running at constant luminosity ATLAS&CMS Luminosity at LHCb IR controlled by displacing the beams T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

17 LHCb running luminosity LHCb has been running beyond the designed performance LHCb designed luminosity: L = cm 2 s 1 with 25 nsec LHCb actual running luminosity: L cm 2 s 1 with 50 nsec i.e. 1.5 more peak luminosities with 1/2 the bunch crossing rate 3 times higher number of pp interactions per event challenge for both trigger and analysis more CPU installed for the event filter farm designed safety margin of the detector LHCb fully exploiting this running condition good prospect for the upgrade T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

18 Quick reminder for LHCb LHCb is a forward spectrometer dedicated for flavour physics pp-c.m. system b b θ b b Both b and b are in the spectrometer. T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

19 Very rapid start of the experiments As ALICE, ATLAS, and CMS, LHCb was ready for physics right from the first collision in 2010 at s = 7 TeV e.g. σ bb B J/ψ( μμ)x (detached J/ψ) 2.2 pb 1 ATLAS NPB2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

20 Very rapid start of the experiments As ALICE, ATLAS, and CMS, LHCb was ready for physics right from the first collision in 2010 at s = 7 TeV e.g. σ bb B + J/ψ( μμ)k pb 1 CMS PRL2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

21 Very rapid start of the experiments As ALICE, ATLAS, and CMS, LHCb was ready for physics right from the first collision in 2010 at s = 7 TeV e.g. σ bb B μd( Kπ)X and B J/ψ( μμ)x LHCb PLB2010 pp s = 7 TeV 25 nb 1 Theory uncertainty T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

22 Significant LHC results in B from 2011 B s0 μ + μ? + T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

23 Significant LHC results in B from 2011 B s0 μ + μ Interests were generated by CDF results with 7 fb 1 data Hypothesis of background fluctuation: p-value of 0.27% excess over the background and SM prediction? CDF PRL2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

24 Significant LHC results in B from 2011 B s0 μ + μ CMS results with 1.14 fb 1 data cut-based analysis CMS PRL2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

25 Significant LHC results in B from 2011 B s0 μ + μ LHCb Conf-note 2011 LHCb results with 0.3 fb 1 data distribution based analysis T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

26 Significant LHC results in B from 2011 B s0 μ + μ LHCb Conf-note 2011 LHCb results with 0.3 fb 1 data distribution based analysis CMS + LHCb CDF results not confirmed Consistent with SM T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

27 Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 D s (φπ)π D s (K K)π D s (KKπ)π D s 3π T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

28 Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution σ τ = 44 fs for D s π and 36 fs for D s 3π σ τ for prompt D s plus π or 3π from the primary vertex making B s mass, i.e. fake B s at τ = 0 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution

29 Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution well calibrated absolute scale of decay time B lifetime measurements 2010 data 36 pb 1 PDG ps PDG ps T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

30 Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution well calibrated absolute scale of decay time efficient and clean initial flavour tag hadron PID of LHCb u K + same side Kaon tag s s b B 0 s signal B p p b-hadron opposite side tag -high p T μ from b -secondary K + (b c s) -secondary vertex charge T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

31 Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution well calibrated absolute scale of decay time efficient and clean initial flavour tag high statistics With 2010 data 36 pb 1 (+c.c) T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

32 Real demonstration of LHCb in 2010 B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution well calibrated absolute scale of decay time efficient and clean initial flavour tag high statistics Δm s = ± 0.11 ± 0.02 ps 1 with full 2010 data 36 pb 1 opposite side tag only c.f CDF Δm s = ± 0.10 ± 0.07 ps 11 with 36 pb 1 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

33 Real demonstration of LHCb now B s -B s oscillation frequency (Δm s ) measurement cleanly reconstructed B s LHCb Conf-note 2011 good momentum and vertex resolutions decay time resolution well calibrated absolute scale of decay time efficient and clean initial flavour tag high statistics Δm s = ± 0.11 ± 0.02 ps 1 with full 2010 data 36 pb 1 opposite side tag only partial fb 1 Δm s = ± ± ps 1 with partial 2011 data 340 fb 1 same + opposite sides tag c.f CDF Δm s = ± 0.10 ± 0.07 ps 11 with 36 pb 1 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

34 LHCb Challenges in 2011 CP violation in B s J/ψφ LHCb Conf-note 2011 Clean B s J/ψφ signal ~8300 (untagged) Decay time distribution of untagged B s J/ψφ T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

35 LHCb Challenges in 2011 CP violation in B s J/ψφ opposite side tag only K + -K S-wave contribution included very good fit behaviour LHCb Conf-note 2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

36 LHCb Challenges in 2011 CP violation in B s J/ψφ LHCb Conf-note 2011 Good agreement with SM T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

37 LHCb Challenges in 2011 CP violation in B s J/ψφ LHCb Conf-note 2011 Γ s = ± ± ps 1 The world best measurement ΔΓ s = ± ± ps 1 A clear evidence for non-zero ΔΓ φ J/ψφ s = 0.13 ± 0.18 ± 0.07 rad The world best measurement ΔΓ s /Γ s = ΔΓ s /Δm s = ± constraint for the CPV in B s -B s oscillations A sl = ΔΓ/Δm arctan (φ Γ φ Μ ) D0 A sl means φ Γ φ Μ 45 too big even with new physics Good agreement with the Standard Model ΔΓ s = ± ps 1 φ s J/ψφ = rad T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

38 LHCb Challenges in 2011 Muon A FS in B 0 K 0 (Κ + π )μ + μ LHCb Conf-note 2011 Β 0 ψ(2s) 309 pb 1 ~320 events J/ψ T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

39 LHCb Challenges in 2011 Muon A FS in B 0 K 0 (Κ + π )μ + μ LHCb Conf-note 2011 BELLE BABAR CDF + LHCb Good agreement with SM T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

Radiative decays @ LHCb B d K 0 γ and B s φγ LHCb Conf-note 2011 b W t

40 Radiative LHCb B d K 0 γ and B s φγ LHCb Conf-note 2011 b W t s γ T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

41 Radiative LHCb B d K 0 γ and B s φγ LHCb Conf-note 2011 b W t s γ 340 pb 1 World best measurement cf: PDG average 0.7 ± 0.3 Final goal for B s φγ: to study decay time dependent CP asymmetry T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

Charmless two-body decays @ LHCb B hh decays CP

42 Charmless two-body LHCb B hh decays CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π b W u + b W t s CDF 1 fb 1 PRL2008 PRL2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

43 Charmless two-body LHCb B hh decays CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π b b W s W u + t LHCb 320 pb 1 clean signal due to PID LHCb Conf-note 2011 B 3 bodies signal B d ππ B s KK B s Kπ T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

44 Charmless two-body LHCb B hh decays CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π b W u + b W t LHCb Conf-note 2011 s LHCb (preliminary) 320 pb 1 World best measurement T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

Charmless two-body decays @ LHCb B hh decays CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π B s0 K + π vs B s0 K π + b W u + b W t LHCb Conf-note 2011 d

45 Charmless two-body LHCb B hh decays CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π B s0 K + π vs B s0 K π + b W u + b W t LHCb Conf-note 2011 d LHCb (preliminary) 320 pb 1 World best measurement May be, B s CP asymmetry is larger and opposite sign T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

46 Charmless two-body LHCb B hh decays CP violation in the decay amplitudes: B 0 K + π vs B 0 K π + B s0 K + π vs B s0 K π + W-exchange diagramme B d K + K B s π + π B d b d W u u s s K b u K + B s W s u d d π π + T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

47 Charmless two-body LHCb B hh decays LHCb Conf-note 2011 CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π B s0 K + π vs B s0 K π + W-exchange diagramme B d K + K B s π + π B d ππ B d Kπ B s ππ signal Good mass resolution Particle ID T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

48 Charmless two-body LHCb B hh decays LHCb Conf-note 2011 CP violation in the decay amplitudes: B 0 K π + vs B 0 K + π B s0 K + π vs B s0 K π + W-exchange diagramme B d K + K B s π + π World best measurements 320 pb 1 cf: CDF measurements: (PRL2011) B d Κ + Κ = (0.23 ± 0.10 ± 0.10) 10 6 B s π + π = (0.57 ± 0.15 ± 0.10) 10 6 Are the B d and B d branching fractions same or not? T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

49 D physics with LHCb Time integrated CP violation in D K + K and π + π Decay time integrated CP asymmetries: A KK CP and A ππ CP D 0 initial f D0 initial f D 0 initial f + D0 initial f and CP asymmetry difference: Δ CP = A KK CP A ππ CP T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

50 D physics with LHCb Time integrated CP violation in D K + K and π + π Decay time integrated CP asymmetries: A KK CP and A ππ CP D 0 initial f D0 initial f D 0 initial f + D0 initial f KK ππ and CP asymmetry difference: V cs V us c V cd V ud c W U-spin W s d s u d u + Δ CP = A CP KK A CP ππ c b, s, u T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November W u V ub V cb {F(m b ) F(m d )} + V cs V us {F(m s ) - F(m d )} KK and ππ: weak amplitudes are with opposite signs if U-spin symmetry holds, interference terms have opposite signs

51 D physics with LHCb Time integrated CP violation in D K + K and π + π Decay time integrated CP asymmetries: A KK CP and A ππ CP D 0 initial f D0 initial f D 0 initial f + D0 initial f and CP asymmetry difference: Δ CP = A KK CP A ππ CP World average Δ CP = ± dominated by CDF T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

52 D physics with LHCb Time integrated CP violation in D K + K and π + π At LHC, large σ cc 6 mb 20 times σ bb Initial tag: D + D 0 π + and D D 0 π LHCb Conf-note 2011 T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

53 D physics with LHCb Time integrated CP violation in D K + K and π + π LHCb Conf-note 2011 LHCb with 500 pb 1 Δ CP = ± ± = ± World best measurement SM prediction difficult, but expected to be at most O(10 3 ) Interesting to see how it develops with more statistics A CP KK and A CP ππ separately in the future Time dependent study in the future Other D-D mixing and CPV parameters have been measured, but not the world best yet. This will change soon! T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

54 I could not show Preparation for the CKM parameter measurements, e.g. γ; reconstruction of B u, d DK, B s D s K, Rare and SM forbidden B and D decays; reconstruction of B, D eμ, μ + μ + +c.c., Spectroscopy with b-quarks; excited B s, b-baryons, Exotic states with c (and b); X, Y, Z, PDF and QCD measurements; dσ 2 /dydp T for W and Z Soft QCD T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

55 Conclusions At LHC, new physics is searched both directly and indirectly. Experiments are all running very well, physics output from the beginning of the run. LHC experiments superseded Tevatron. LHCb starts to provide the world best measurements in many B and D decays with ~360 fb 1 of data. So far, CP violation and rare decay measurements are in agreement with the Standard Model predictions. LHCb collected 1 fb 1 of data this year. Results expected for the winter/spring conferences. T. Nakada (EPFL) KIAS Phenomenology Workshop, Seoul, November

The LHC Heavy Flavour Programme

The LHC Heavy Flavour Programme Tatsuya Nakada CERN and EPFL LHC Flavour Workshop 26-28.03.07, CERN 1 Contents 1) Introduction 2) LHC Experiments 3) Physics with 2008 data 4) Flavour Physics >2008 5) Conclusions