Mauro Donega’ - CDF collaboration meeting February 3, 2006 B d,s ->h 1 h 2 : BR, CP asymmetries, and lifetimes S. Budroni, S. Donati, M. Donega’, S. Giagu, M. Morello, G. Punzi, D. Tonelli CDF Collaboration Meeting February 3, 2006   Notes: 6175, 6356, 6357, 6453, 7066, 7978, 8057 (+linked notes on dE/dx calibrations and isolation studies)

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Physics motivations B d,s ->h 1 h 2 = Bd->k , Bd-> , Bs->KK, Bs->K  Accessible to B factories: Bd->k , Bd->  Only at TeVatron (until >2007): Bs->KK, Bs-> K  Possible measurements: Today: direct CP asymmetry in Bd->k , Bs-> K  (counting experiment) Future: CP asymmetry in mixing Bd-> , Bs->KK (requires time dependent analysis) Short term goal: Using Bd->k , Bd->  BR, constrain the relevant hadronic penguin parameters. Long term goal: combine time-dependent Bd->  and Bs->KK asymmetries (+other external input) to measure    Tree Penguin PHYSICAL REVIEW D 66, Physics Letters B –320

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Physics motivation (cont’d) B s described as a two states system. Evolution through Schroedinger equation: off diagonal terms ->mixing M 12,  12,  = arg(- M 12 /  12 ) What we measure:  m = M H –M L ~ 2|M 12 |  =  L –  H ~ 2|  12 |cos(  ) SM:  ~0 -> CP eigenstates ~ mass eigenstates B s -> is predicted to be 95% CP even => c  (Bs->KK) ~1/  L Bs->KK lifetime combined with FS (  ) can give . Measurement of Bs->KK lifetime can be strongly affected by new CP violating physics => sensitivity to New Physics _

Mauro Donega’ - CDF collaboration meeting February 3, 2006 DATA Fitter Kinematics+PID Raw fractions Fitter Kinematics+PID+Lifetimes Acceptance corrections Lifetimes BR and ACP Signal extraction Optimized sample Two groups: BR, ACP and Lifetimes worked on the same data sample: Ideal x-check of the common results !

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Data and MC samples Dataset: xbpp0d ~355 pb^-1 (BPAK good run list applied) Triggers: B_PIPI B_PIPI_HIGH_PT (~7% of the total) MonteCarlo: BMC framework Simulated the four signal modes: B d ->K , B d -> , B s ->KK, B s ->K  Reconstruction: CharmMods – Track refit with L00 Primary vtx from beamline

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Signal extraction Optimization performed independently by the two groups Lead to similar set of cuts: BR, ACPLifetimes Isolation > > 0.5 Pt(trk1)+Pt(trk2) - > 5.95 (GeV/c) D0(B) < 70 (um) < 51 (um) Min(|d0(trk1)|,|d0(trk2)|)- > 180 um Lxy > 300 um - Prob(  2 vtx 3D)- > 0.01  2 vtx 3D < 15- S/B~ 2

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Background mass description combinatorial B d/s  /K Include B d/s  /K in the mass description (little bias to the lifetimes, included as systematic uncertainty) Fit combinatorial bkg Shape fraction Lifetimes B->hh signals to be disentangled BR ACP

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Disentangling the signal fractions BPAK calibrations Bd+-Bd+- Bd  K-+Bd  K-+ B d  K +  - Bs  K+K-Bs  K+K- mass     e   K p Momentum (GeV/c) 2

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Extract the lifetimes MC based lifetime extraction (tested on B->D  decays CDF7386) = Background described with a template On the right sideband (combinatorial only) = Events after trigger+offline cuts Lifetime MC ev/ev ct error

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Raw fractions results F(B d  K  )62.8± ±1.7 F( B d  +  - )13.7± ±1.4 F(B s  KK)22.2± ±1.6 F(B s  K  )1.3± ±1.0 Lifetimes BR, ACP Compatible results !

Mauro Donega’ - CDF collaboration meeting February 3, 2006 BR ACP =XXX ± (stat) ± 0.013(syst)

Mauro Donega’ - CDF collaboration meeting February 3, 2006 ct (cm) Lifetimes results c  (B d ) 452 ± ±4 c  (B s  KK) 463± ± 53  CP /  CP ± 0.23 c  (B d ) floating c  (B d ) PDG constrained z2 p 1 +p 2  mass z1 In agreement with world average 460 ± 4 um

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Systematic uncertainties 5.6 um Lifetimes BR ACP

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Status (360 pb -1 ) and Plans (1 fb -1 ) Status: BR and ACP pre-blessed on January 26 th, 2006 Lifetime measurement blessed on January 26 th, 2006 Plans: Bless BR and ACP 360 pb -1 and move to 1 fb -1 Lifetimes move to 1 fb -1 : Data skimming + MC production (in progress) dE/dx calibrations (~done)

Mauro Donega’ - CDF collaboration meeting February 3, 2006 Summary The charmless two body B decay sample is Extremely Rich ! And leads to world class B physics measurements. We are upgrading the BR and ACP measurements and for the first time we measured the lifetimes on 360 pb -1 : c  (B d ) = 452 ± 24 ± 6 um c  (B s  K + K - ) = 458 ± 53 ± 6 um  (CP) /  (CP) = ± 0.23 ± 0.03