Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 1 CPV in B → D (*) K (*) (and B → D K  ) in BaBar and Belle Outline: CPV in B → D (*) X s theoretical ideas experimental issues experimental results  B ∓ → D (*)0 K (*) ∓  B 0 → D (*)0 K (*)0 some other approaches summary

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 2 CPV in B → DX s Φ 3 (γ ) ≡ arg(-V ud V * ub / V cd V * cb ) V cd V * cb V td V * tb V ud V * ub Φ3(γ)Φ3(γ) Φ2(α)Φ2(α) Φ1(β)Φ1(β) CPV in interference between b → c & b → u B → DX s is a good place to look theoretically clean: only tree diagrams interference between B → D (*)0 K( X s ) ⊕ B → D (*)0 K(X s ) f experimentally challenging: sensitive to experimentally challenging: sensitive to

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 3 D → f CP ( G ronau, L ondon & W yler method ) δ - relative strong phase A (B - → D 0 K - ) δ 2Φ32Φ3 δ  2A (B + → D CP K + ) A (B - → D 0 K - )= A (B + → D 0 K + )  2A (B - → D CP K - ) A (B + → D 0 K + ) amplitude triangles extensions and modifications various f various X s, (D) many observables... statistics required: ∼ 0.5 ab -1 Ways to measure Φ 3 in B → DX s PROBLEMS:  r = A (B - → D 0 K - )/ A (B - → D 0 K - ) ~ 0.1(0.2)  A (B - → D 0 K - ) difficult to measure directly

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 4 Experimental issues ΔE (B - → D 0 h - )  E  -49 MeV for DK - Use beam constraints to reconstruct B: Use beam constraints to reconstruct B: Apply tight K-ID cut: Apply tight K-ID cut: M bc (GeV) K/  separation Babar : dE/dx in SVT & DCH, DIRC Belle: dE/dx in CDC, TOF, ACC ≥2.5  (K/  ) separation up to 3.5 GeV K/  separation Babar : dE/dx in SVT & DCH, DIRC Belle: dE/dx in CDC, TOF, ACC ≥2.5  (K/  ) separation up to 3.5 GeV

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 5 Experimental issues Continuum suppression: multidimensional cuts exploiting event topology (Fox-Wolfram moments, thrust...) angle of B-flight direction... Background suppression from other B decays depends on specific final states: veto for some B-decays,.... Signal extraction: Maximum likelihood fits with signal shape from MC and data control samples, background from side bands and off-resonance data (combinatorial), MC (B-decays)

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 6 Preliminary B - → D 0 h - measurements 56 fb -1 D 0 →K  D 0 →K  D 0 →K  0  E(GeV) ± ± ± 0.2)%( ± 0.6 )%(7.70.9± 0.7)%(9.91.3± CLEO, hep-ex/ fb -1 Babar, hep-ex/ fb -1 Belle, PRL 87,111801(2001 ) 10.4 fb -1 h - identified as K Signal extracted wit ML fit to the  E,M bc,PID(  /K) For other B→D(*)K - modes see Belle, PRL 87,111801(2001)

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 7 B - → D CP K fb -1 Preliminary D 1  D CP=+ D 2  D CP=- B D1KB D1K D 1 = KK D 1 =   E(GeV) 24.2  7.2 Observables: asymmetries branching ratios Observables: asymmetries branching ratios 3 independent equations with 3 unknowns ( Φ 3, r,  ) = 0.17 ± 0.23(stat) ± 0.08(sys) = 1.06 ± 0.26(stat) ± 0.17(sys )

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 8 B - → D CP K - D 1 =KK,  D 2 =K s  , K s , K s , K s , K s  ’ 78 fb -1 hep-ex/       6.5 Signal yields extracted with a likelihood fit to the  E = ± 0.17(stat) ± 0.05(sys) = 1.41 ± 0.27(stat) ± 0.15(sys) = 1.21 ± 0.25(stat) ± 0.14(sys) = 0.06 ± 0.19(stat) ± 0.04(sys) sin 2 ( Φ 3 ) ≤ r  1/4 | | sin 2 ( Φ 3 ) ≤ r  1/4 | |

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 9 Similar analysis can be performed with K*- replacing K- 88 fb -1 Preliminary cos  hel from P→PV No indication for non-resonant DK  MK *- D 0 → K , K ,K  0 = ± 0.33(stat) ± 0.07(sys) = 0.19 ± 0.50(stat) ± 0.04(sys) B - → D CP K* - (6.1 ± 1.6(stat) ± 1.7(sys)) x CLEO 13.1   D 1 =K + K -,  +   D 2 =K s  , K s , K s  7.2  

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 10 B → D *0 K *- ALL 81.2 fb -1 Preliminary B - → D* 0 K* - B→V V can be also used, angular analysis required, B→V V can be also used, angular analysis required, D *0 → D 0  0 D *0 → D 0  (8.0 ± 1.0(stat) ± 1.2(sys)) x (7.7 ± 2.2(stat) ± 2.6(sys)) x CLEO

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 11 both amplitudes are color suppressed r ~ 0.4 B 0 → D 0 K ( * )0 B 0 → D 0 K* 0, K* 0 → K +  - (kaon tags B 0 flavour) rates and asymmetries B 0 → D 1,2 K* 0 ⇒ Φ 3 isospin relations ⇒ extract Φ 3 and  B 0 → D 0 K 0 s, B 0 – B 0 mixing time dependent asymmetries (B 0 -decay vertex needed)

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th fb -1 B 0 → D 0 K ( * )0 PRL 90, (2003) M(D 0 ) sidebands 27.0   8.4 EE 90% CL V ub.

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 13 PDG | | | | | | 78 fb -1 D  K  56 fb -1 D  K  88 fb -1 D  K  78 fb -1 D  K  78 fb -1 D  K  Summary of Br’s, event yields,.....

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 14 Some other approaches  Atwood,Dunietz, Soni (ADS): use doubly Cabibbo-suppressed D decays  Dalitz plot analysis of B  DK   B  DK, Dalitz plot analysis of multibody D decays ( e.g. D  K s  +  - )  r ~ 1, Br ~ b cb uu uuusuuus cuuscuus u Both amplitudes are color allowed

Maria Różańska, INP Kraków HEP2003 Europhysics Conference –Aachen, July 18th 15 Summary and outlook No direct CPV observed in B → DX s, no direct constraints on Φ 3 yet, but there is a steady progress:  new relevant decay modes observed:  B - → D K (*)- D → f CP, CP=+,-  B 0 → D K (*)0 o other analyses in progress  accelerator performance  KEKB: L peak >10 34 cm -2 s -1 PEP-II: L peak >6  cm -2 s -1 o Belle and BaBar aiming for ≈ 0.5 ab -1 in 2005 some meaningful constraints on Φ 3 possible by that time  new theoretical ideas  precise measurements in D sector