Reaching for  (present and future)

1. Andrey Golutvin ITEP/Moscow Reaching for  (present and future)

2. Unitarity Triangles Bd0  p+ p- Bd0  rp BS0  DS p Bd0  DK*0 BS0  DSK Bd0  D* p, 3p Bd0  J/yKS0 BS0  J/y f This talk V ud Vub*  = arg | | -V cd Vcb*

3. There are a few methods of determining  CP violation in Interference of Mixing & Decay CP violation in Decay • Rates and asymmetries in K Decays • Amplitude triangles for B Dcp0K • (GLW method) • + extensions/modifications • Time dependent asymmetries • in Bd+- and BsK+K- decays • assuming U-spin symmetry • Time dependent flavor tagged • analysis of • BsDsK- decay • BdD*+ decay

4. Data Samples (present and future) Results presented today are based on 81.2 fb-1(BaBar) and 78 fb-1(BELLE) That corresponds to 88 and 85 mln BB pairs (part of data sample) Statistics available today at B-factories 300 mln BB pairs - - - In 2006 one expects  1.2 bln BB pairs - In 2008 after 1 year of LHCb (and BTeV) operation  1012 bb pairs Super Bd-factory: 1.5 to 5 bln of “clean” BB events depending on achieved luminosity -

5. gfromB  K decays K Significant interference of tree and penguin amplitudes Expect potentially large CP asymmetries QCD penguins play the dominant role • Difficulties: • Theoretical • EW penguins • SU(3) breaking + (FSI) effects • Experimental • small BF, qq background • Particle ID is crucial Measurement of the ratios of BF and ACP may provide constraints on andstrong phase  dir _

6. Summary of BFs [10-6] From J.D. Olsen talk at the CKM workshop 2003

7. Comparison of BF No sign of rescattering yet Present precision is dominated by statistical errors In a few years statistical and systematical errors should become comparable

8. A Specific Model: QCD Factorization Beneke et. al., Nucl. Phys. B606, 245 (2001) Data (2001) Data (2003) Inconsistent? Data start to constrain models

9. CP asymmetries (allows one to eliminate dependence on the strong phase ) Largest deviations: 2s each in K+p-(BaBar), r+p-(BaBar), and K+p0(Belle)

10. In a few years statistical precision in the measurements • of Branching Fractions (BK/) should reach the level • of systematic error, 2-4% depending on decay mode • Extraction of  will be dominated by theoretical • uncertainties BaBar: K0+ 80 fb-1 In 1 year BTeV expects: 4600K0+ events (with S/B = 1) 62100 K-+ events (withS/B=20)

11. Amplitude triangles GLW method B- DCPK- where DCP=(1/2)(D0D0 ) A(B- DCPK-)  |A(B-D0K- )| + |A(B-D0K- )|eiei A(B- DCPK+)  |A(B-D0K+ )| + |A(B-D0K+ )|e-iei CP-even states: K+K-, +- CP-odd states: Ks0, Ks, Ks, Ks, Ks’

12. can be extracted from the reconstruction of two triangles Experimental problems: A(B-D0K-) is small squashed triangles DCSD lead to the common final states for D0 and D0 (color suppressed A is of the same order as color favored  DCSD) Experimental observables: BF(B-D1,2K-) / BF(B-D1,2-) , A1 and A2 R1,2 = BF(B-D0K-) / BF(B-D0-) allow, in principle, to extract RDK- ,  and 

13. BaBar reconstructed D1K- K+K- (7.41.70.6)% R1= (8.310.350.20)% +0.09 AD1K-= 0.170.23 -0.07 D1K-and D2K- BELLE studied both R1 = 1.21  0.25  0.14 R2 = 1.41  0.27  0.15 AD1K-= +0.06  0.19  0.04 AD2K-= -0.18  0.17  0.05 No constraints on  possible with this statistics … Needed: significantly higher statistics precision measurements of D Branching Fractions

14. B0D0K(*)0 Mode Two comparable color-suppressed amplitudes Triangles are not as squashed as in B DKcase _ _ BELLE +1.3 BF(B0 D0 K0) = (5.0 0.6)  10-5 -1.2 _ _ +1.1 BF(B0 D0 K*0) = (4.8 0.6)  10-5 -1.0 Hope to see soon B0 D0 K*0 decay Present Upper Limit is BF(B0 D0 K*0)  1.8  10-5

15. ADS variant of the amplitude triangle approach: B-  D0[fi] K- andB-  D0[fi]K-, fi= K-+ or K-+0 Use large interference effects Experimentally challenging since BF of O(10-7) are involved Dalitz plot analysis of D  KS+ - for B-DK- and B+DK+decays KS+- receives contributions from: B- D0K- D0K*-+ K*- KS- B- D0K- D0K*+- K*+ KS+ B- D0K- D0KS0 0 +- B- D0K- D0KS0 0 +- Enough information to extract  for any magnitude of 

16. B0D*- Mode _ u c + D*- _ favored suppressed d d _ _ b c b u _ B0 + B0 D*- _ _ d d d d Suppressed/favored < 10-2 Small CP-violating effect expected Time evolution: (BD*)  (1+RD*2)  (1-RD*2)cos(mt)  2 RD*sin(2+) sin(mt) (2 + ) is extracted from the measurement of 4 time-dependent asymmetries RD* can be estimated using BF(B0Ds+-): BF(B0Ds+-)  fDs2 BF(B0D*-+) RD*2   tan2c fD*2

17. Evidence for B0Ds+- Br(B0Ds+-)Br(Ds++) BaBar (1.13  0.33  0.21)x10-6 BELLE (0.86  0.11) x10-6 +0.37 -0.30 BELLE have measured Br(Ds++)=(3.720.39 ) x10-6 using full/partial reconstruction method +0.47 -0.39 RD*  0.022  0.007

18. D*+- Data Samples (partial reconstruction) 20 fb-1, 6970 ± 240 events B0 = 1.510 ± 0.040 ± 0.041 ps 30 fb-1, 3430 ± 80 events m = 0.509 ± 0.017 ± 0.020 ps-1 (sin(2+))   0.15 for 1000 fb-1 T. Gershon (CKM workshop, 2003) or (2+)  10o

19. gfromBs D-s K+ , D+s K- Same principle as for B0D*- Since  is small  sensitivity should not depend on the value of  Two decay modes with comparable amplitudes,   10-4 each  can be determined from the measurement of 4 time-dependent asymmetries (assuming that  is fixed from Bs mixing) Contribution from NP is unlikely ! Looks as most clean method to measure 

20. , K Bs K K Ds  BsDsp,DsK kinematics at LHCb 72k Ds 8k DsK •  ~ 6.5 MeV/c2 s = 168 mm s = 418 mm Bs vtx resolution (mm) Ds vtx resolution (mm) Dsmass (GeV)

21. Importance of Particle ID • Needed: • Hadronic trigger • K/p separation • Good proper time resolution

22. In one year of LHCb running: 8k BsDsKreconstructed events Sensitivity slightly depends on strong phase difference (T1/T2) and xs • Assumptions: • 3k tagged BsDsK- • 30% background • 30% mistag LHCb: ()  10º for xs = 15 ()  12º for xs = 30 BTeV: ()  8º

23. g from B(s) pp, K Kproposedby R. Fleischer Measure time-dependent asymmetries in B0 +- and Bs  K+ K- decays to extract  where dexp(i) is a function of T and P amplitudes Assuming U-spin flavor symmetry: d=d’ and =’ can be extracted

24. BS K+ K- B0  +- g from B(s) pp, K K input values • Evaluation of and sensitivity from time-dependent measured asymmetry

25. In one year of LHCb operation : BS K+ K- increasing xs B0  +- (A dir )  (A mix )  0.054 BS K+ K- (A dir )  (A mix )  0.043 Sensitivity to : assuming 4 years of data taking (4x27k Bd and 4x35k BsKK) B/S = 0.8 and 0.55 correspondingly tagging: D2 = 6.4% Combining all information: () = 2.50

26. Conclusions  can be measured both using CPV in decay (time-integrated) and in the interference of mixing and decay (time-dependent) Only trees (1) Theoretically clean: b c X Amplitude triangles BsDsK Trees + loops (2) Experimentally easier b  hh (h = non-c) Experimental precision on BF already below 10% level Clear theoretical strategy how to extract  is still missing Measurement of rare decays with BF  10-7could help Sensitive probe for New Physics (1) vs (2)

27. —sum BdK BsKK Bd BsK  Expectations from CDF Run IIa ACP=ACP(dir)cos(mt) + ACP(mix)sin(mt) • /K/KK/K separation: • Inv. mass ~ 20 MeV/c2 • Kinematical variables • dE/dX • Md << Ms RunIIa: ACP(dir, mix)~0.2 (Bd) ~0.1 (BsKK) () = ±10(stat)