physics program (searching new physics hidden in beauty and charm) S. T Jampens LAPP (CNRS/IN2P3 and Université de Savoie)

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1 phyic program (earching new phyic hidden in beauty and charm) b b b S. T Jampen LAPP (CNRS/IN2P3 and Univerité de Savoie) On behalf of the LHCb collaboration

Trigger cheme Expected phyic performance (example) in2β

2 Outline LHCb experiment LHCb environment at LHC LHCb pectrometer Tracking, PID, Flavor tagging performance and Trigger cheme Expected phyic performance (example) in2β Meaurement of γ B mixing phae 2β _ b penguin B µ+µ B K* ll Charm phyic 2

3 Flavor Phyic: The Quet of New Phyic The main purpoe of B (D and K) phyic i now to earch for new phyic effect in flavor mixing, CP violation and rare decay. the 2nd generation b phyic experiment: puruing the NP earche with preciion meaurement (and if NP i dicovered, put contraint on it flavor tructure) Three major theme: 1) preciion determination of CKM element to eek deviation from SM 2) New phyic via CP violating phae 3) New phyic via rare decay Look for everywhere: conitency check of UT (angle and ide): need more tatitic, ep. need improvement for (for Reference UT in Tree v Loop) and Lattice QCD compare different meaurement of the ame quantitie, one which i inenitive and another one which i enitive to NP (e.g., in2β from B0 J/ψ KS and B0 φks) F =1 FCNC rare decay (e.g., b γ, b l+l, B() µµ) F =2 FCNC mixing (e.g., B mixing phae 2 with B J/ψ φ) etc. 3

4 LHCb: > 600 cientit 47 univeritie and laboratorie 15 countrie Geneva CERN A Large Hadron Collider beauty experiment for preciion meaurement of CP violation and rare decay LHC Tunnel 4

5 LHC cooling tatu and tartup Cooling down i performing well, aiming for machine cooled down in early July Beam injected end July early Augut. Firt colliion 1 2 month later Luminoity 1031 cm 2 1, = 10 TeV 5

LHCb environment @LHC large cro ection: 500 µb (230 µb in 4.9 > η >1.9 (forward region)) All pecie of B hadron produced: (B±, Bd, B, Bc, b baryon) [40%,40%,10%,0.1%,10%] σbb/σinel = 0.

6 LHCb large cro ection: 500 µb (230 µb in 4.9 > η >1.9 (forward region)) All pecie of B hadron produced: (B±, Bd, B, Bc, b baryon) [40%,40%,10%,0.1%,10%] σbb/σinel = 0.6% at LHC: trigger i a major iue bb correlation (PYTHIA) bb production correlated and harply peaked forward backward: ingle arm pectrometer i OK ince b quark are correlated important for tagging Luminoity ℒ=2x1032 cm 2 1 (de tuned beam): clean environment ( n = 0.5) le radiation damage B hadron (in acceptance) in 107 ec (1 year, 2 fb 1) 10 fb 1 by

tation Dipole magnet VELO proton beam colliion point proton beam ~1 cm B Requirement for B

7 LHCb: Forward Spectrometer VELO: Vertex Locator (around interaction point) TT, T1, T2, T3: Tracking tation RICH1 2: Ring Imaging Cherenkov detector ECAL, HCAL: Calorimeter M1 M5: Muon tation Dipole magnet VELO proton beam colliion point proton beam ~1 cm B Requirement for B phyic: excellent tracking and vertexing (σm, στ) excellent particle ID flexible and efficient trigger 7

8 View of the LHCb cavern Muon detector Calorimeter RICH 2 OT+IT Magnet RICH 1 VELO Intallation complete, commiioning well underway 8

9 PID, tracking and tagging performance Average b decay track reolution: impact parameter: ~30 µm momentum: ~0.36% Typical B reolution: proper time: ~40 f (eential for B phyic) ma: 8 18 MeV/c2 PID average performance: kaon ID efficiency: 95% π mi ID: 5% Good K/π eparation in the GeV/c range Ma reolution B µµ 18 MeV/c2 B D π 14 MeV/c2 B Jψ φ 16 MeV/c2 B J/ψ φ 8 MeV/c2 * (*) with J/ψ ma contraint With PID Expected tagging performance: (on triggered and elected MC event) ε(1 2ω)2= 7 9% for B ε(1 2ω)2= 4 5% for Bd ππ invariant ma 9

10 Trigger Performance and Rate Johanne Albrecht' talk Algorithm and performance: Hardware level (L0), max. 1 MHz output rate: algorithm mature Software level (HLT=High Level Trigger): prototype available within time budget for a limited et of channel L0*HLT efficiencie: typically 30% 80% for offline elected ignal event, depending on channel Output rate Event type Phyic 200 Hz Excluive B candidate B (core program) 600 Hz High ma di muon J/ψ, b J/ψX (unbiaed) 300 Hz D* candidate Charm 900 Hz Incluive b (e.g., b µ) B (data mining) Event ize: ~ 50kB 10

11 LHCb: Phyic Program (example) phy.web.cern.ch/lhcb phy/dc04_phyic_performance/ 11

12 Sin2β with B0 J/ψ KS Expected to be one of the firt CP meaurement: Demontrate (already with 0.5 fb 1) that we can keep under control the main ingredient of a CP analyi, in particular the tagging performance extraction from the control ample B0 J/ψ K0* Yeterday enation i Today calibration and Tomorrow background hep phyic' adage Senitivity: 236k event/2 fb 1 with B/S= 0.6 (bb) and 7.7 (prompt J/ψ) σ(in2β) = [B factorie: (850 fb 1)] 2 fb 1 (fatmc, inc. bkg.) 12 Proper time t(p)

Meaurement of the angle γ B+ D(*)0K(*)+: Tree: b c, dominant B b u W Tree: b u, color uppreed u c u K ( ) D W b B u ( )0 _ u c u D( )0 K ( ) Recontruct D in final tate acceible to both D and D 0: 0

13 Meaurement of the angle γ B+ D(*)0K(*)+: Tree: b c, dominant B b u W Tree: b u, color uppreed u c u K ( ) D W b B u ( )0 _ u c u D( )0 K ( ) Recontruct D in final tate acceible to both D and D 0: 0 GLW: D decay to CP eigentate ADS: D decay to flavor tate GGSZ: D decay to KSπ +π (interference in Dalitz plot) σtat(γ) [2 fb 1] B mode D mode Method B+ DK+ Kπ, KK/ππ counting,ads+glw B+ DK+ KSππ Dalitz, GGSZ 7 12 B+ DK+ KKππ 4-body Dalitz 18 B0 D0K*0 Kπ, KK, ππ counting,ads+glw tree decay only 9 Other mode under tudy: B D*(D Kπ, KK, ππ)k, B D( Kπππ)K,

14 2β+γ from B0 DK Two tree decay (b c and b u), which interfere via B mixing: can determine 2β+γ hence γ in a clean way imilar to 2β+γ extraction with B0 D*π, but with the advantage that the two decay amplitude are imilar (~λ3) and therefore their ratio can be extracted from data LHCb expect 6.2k event/2 fb 1 Bbb/S < 0.18 (@90 CL) B Dπ background 15±5% after PID cut extract 2β+γ, trong phae difference and amplitude ratio (B Dπ (140k/2 fb 1) alo ued in the fit to contrain other parameter (mitag rate, m, Γ,...)) σ(2β+γ) = 9 12 with 2 fb 1 14

15 _ 2β: B mixing phae with b cc 2β i the trange counterpart of 2β: CKMfitter Summer 2007 β very mall in SM and well predicted: ( ) Could be much larger in preence of New Phyic Golden b cc mode i B J/ψφ: but... angular analyi needed to dientangle CP even and CP odd contribution A CP t = f in 2 in m t coh t /2 f co 2 inh t/2 Current experimental ituation: CDF: 2k, 1.35 fb 1 +2β CL D0: 2k, 2.8 fb 1 +2β = LHCb enitivity with 2 fb 1: 131k B J/ψ(µµ)φ event (before tagging), Bbb/S = 0.12, σt = 36 f σtat(2β) = σtat( Γ/Γ) = PRL 100, (2008) arxiv: [hep ex] Add alo pure CP mode (J/ψη( ), ηcφ, DD) low yield, high background ~25k, σtat(2β) = With 10 fb 1, obtain >3σ evidence of CP violation (2β 0), even if only SM 15

16 Contraint on NP from 2βmeaurement NP in B mixing: amplitude M12 parametrized with h and σ: M 12 = 1 h e 2i M SM 12 m, Γ and ASL 0.2 fb 1 σ(2β)=0.1 LHCb can exclude already a ignificant region of allowed phae pace with the very firt data or... 16

17 _ b hadronic penguin decay Bd d b B ± Vcb W Vc * d b t Vt * φ d c Penguin d φ c J/ψ c W± b ± Vcb W Vc * Tree c Vt b K b Vt b W± Vt * t φ K J/ψ φ Time dependent CP analyi of pure penguin decay into CP eigentate (B φφ: CP violation < 1% in SM, angular analyi required) Channel Yield (2 fb 1) B/S Weak phae B φ K 920 < 1.1 σ(in(2βeff)) = 0.23 B φφ 3100 < 0.8 σ(2β,eff) =

18 B K*l+l Electroweak penguin. Many obervable: Forward Backward aymmetry: AFB(=m )=(NF NB)/(NF+NB) Β 2 ll 0 θ µ+ Κ µ Zero of AFB() [0SM= GeV2/c4] FL and AT(2) (long. pol. and tran. aym.) QCDF: EPJ C41 (2005) 173 SCET: EPJ C47 (2006) 625 Ratio of ee and µµ mode Current experimental ituation: BR(B0d K*0 µ+µ ) [10 6]= HFAG Winter 2008 [Belle, BABAR, CDF] Senitivity (2 fb 1): 7200 evt, B/S~0.5 σ(0) = 0.5 GeV2/c4 18

19 B K*l+l other obervable baed on tranverity amplitude (A0,A,A//) Fitting projection of φ,θl,θk* angular ditribution can give acce to the fraction of longitudinal polarization FL and the tranvere aymmetry AT(2) Stat. preciion in the region = m2μμ [1, 6] (GeV/c2)2 where theory calculation are mot reliable 2 fb 1 AT(2) FL AFB 10 fb 1 ±0.42 ±0.16 ±0.016 ±0.007 ±0.020 ±

20 B 0 µ + µ B µµ helicity uppreed: Well predicted in SM: BR(B µµ) [10 9] = CKMfitter Summer 2007 BR (x10 9) enitive to NP with S or P coupling 90% CL imit on BR (only bkg i oberved) Expected final CDF+D0 limit Event election: main iue: background rejection, dominated by combinatorial bb µµx (uppreed by ma and vertex reolution) SM Yield (2 fb 1): Signal: 30 Bkg: 83 Uncertainty in background prediction SM prediction Integrated luminoity (fb 1) Current limit from Tevatron: CDF: BR < 5.8x10 CL D0: BR < 9.3x10 CL PRL 100, (2008) Note 5344 CONF 0.05 fb 1 overtake CDF+D0 0.5 fb 1 exclude BR value down to SM 2 fb 1 3σ evidence of SM ignal fb 5σ obervation of SM ignal

21 Charm Phyic LHCb will collect a large tagged D* D0 π ample: (alo ued for PID calibration) a dedicated D* trigger i foreeen for thi purpoe D* tagged ignal yield in 2 fb 1 (from b hadron only) tag D0 and anti D0 flavor with π from D*± D0π± D0 K+π right ign 12.4 M D0 K+π wrong ign 46.5 k D0 K+K 1.6 M Intereting (enitive to NP) and promiing earche/meaurement: Time dependent D0 mixing with wrong ign D0 K+π σtat(x 2) ~0.14x10 3, σtat(y ) ~2x10 3 with 2 fb 1 Direct CP violation with D0 K+K AΓ 10 3 in SM (current value [HFAG]: (1.2±2.5)x10 3), up to 1% with New Phyic Expect σtat(aγ)=1.1x10 3) with 2 fb 1 D0 µ+µ BR in SM, up to 10 6 (~current limit) with New Phyic Expect to reach down to ~5x10 8 with 2 fb 1 21

22 Concluion Very intereting reult will come already with firt 0.5 fb 1 (~end of 2009) of data: B J/ψφ: 2β meaurement with 0.05 preciion B µµ: BR limit down to SM value Bd K0*µµ: 1800 event, overtaking B Factorie tatitic Thi wa only MC! The tartup of LHC i coming: looking forward to tarting working with real data and ucceful machine tartup "A new era in human knowledge ha jut tarted......a lot ha already been found, but what i till to be dicovered i more!" [Galileo peaking with Sagredo in "Galileo life", by B. Brecht] 22

B physics results from the Tevatron mixing and CP violation

B physics results from the Tevatron mixing and CP violation phyic reult from the Tevatron mixing and CP violation for the CDF and DØD collaboration Moriond EW 2009 La Thuile, Italy 1 Introduction Mixing meaurement M (DØ & CDF) Semileptonic aymmetry A l Mixing interference