1. BR = (14 +6 -5 (stat) ± 2(syst) ± 5 (BR))  10 -5 From PDG * From MC * BR(  needs to be rescaled for f s /f d From Data b->sss pure penguin amplitude Bs    B ±   K ± New Physics has a chance to compete! B   K*: polarization discrepancy Bs    is the Bs counterpart of Bd   K* Unexpected result (3s effect) from sin(2  ) measure from penguin dominated modes) Measuring angular distribution of decay products determine polarization amplitudes and their relative phases through interference effects: CP violation ΔΓs … Blind Analysis: Normalize rate using another B s  VV decay: B s  J/   : NO production ratio of B s vs B d (f s /f d ) one   K + K - in the final state some systematic on efficiency cancel sizeable rate B s    First observation Charmless B decays at CDF Mauro Donegà Université de Genève On behalf of the CDF collaboration LAYER 00: 1 layer of radiation-hard silicon at very small radius (1.5 cm) (expected 50 fs proper time resolution in B s  D s  ) COT: large radius (1.4 m) Drift Chamber 96 layers, 200ns drift time Precise P T above 400 MeV/c Precise 3D tracking in |  |<1  (1/P T ) ~ 0.1%GeV –1 ;  (hit)~150  m SVX-II + ISL: 5 + 1 (2) layers of double-side silicon (3cm < R < 30cm) Standalone 3D tracking up to |  |= 2 Very good I.P. resolution: ~30  m (~20  m with Layer00) TIME OF FLIGHT B =1.4 T TOF: ~ 100ps resolution, 2sigmaK/  separation for tracks below 1.6 GeV/c (significant improvement of B s flavor tag effectiveness) 35  m  33  m =  47  m (resolution  beam) Primary Vertex Secondary Vertex B Decay Length Lxy d = impact parameter Trigge on 2 displaced tracks : Silicon Vertex Trigger ALL b-hadrons B d, B s,  b K/  separation: >1.4  @P T >2 GeV/c …no ev/ev PID separation This PID performance implies statistical separation of K-pi with resolution 60% of a “perfect” PID e p k   893±47 B  hh’ events BdBd BsBs Bd kBd k Bs kkBs kk B d   Bs  kBs  k Invariant mass  hp (GeV/c 2 ) BKG fraction (float) BKG Likelihood Sum over the 4 channels Likelihood variables: ΔΓ s /Γ s = 0.12 (Standard Model) B s  KK = 100% short eigenstate (HFAG2005) BR(B d  K  ) = 18.2 x 10 -6 (PDG 2004) f s = 0.107 f d = 0.397 B  hh’ the future: Higher precision BR(B s  KK) B s  KK lifetime: ΔΓ s Precision Acp(B d  Kπ) (eventually1%) B s  Kπ BR and direct Acp Tagged time-dependent measurements further ahead: Acp parameters for B d and B s 180 pb-1 360 pb-1 B  hh’ 180 pb -1 Luminosity used in the analyses of this poster 180  mass Extended unbinned maximum likelihood fit to : M KKK M  helicity angle dE/dx Helicity angle Measure at the same time: N(B ±   K ± ) A CP (B ±   K ± ) kaons pions B u,d   X B ±  K *0  B±f0K±B±f0K± comb ID + PDG = BR(B ±  J/  K ± ) 47.0 ± 8.4439 ± 22NBNB B ±   K ± B ±  J/  K ± With dataset now on tape new Bs modes should be visible (B s  K* 0 K* 0, B s   ρ): And other charmless decays are currently under study: B d(s)  K *+ p - (K - ) fV 0 (as L b  fL 0 ) Next round with : ~360 pb -1 Better tracking Improved PID Bs   Bs    B± K±B± K±