Rare Hadronic B Decays

Transcription

1 XLI st Rencontres de Moriond QCD and High-Energy Hadronic Interactions La Thuile, Italy, March 18-5, 6 Rare Hadronic B Decays Jürgen Kroseberg Santa Cruz Institute for Particle Physics University of California, Santa Cruz on behalf of the Collaboration Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 1

2 Outline 1 B decays to open charm Charmless decays study of decay mechanisms factorization tests charm counting search for new physics [complementing Ben Lau s presentation earlier today] Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6

3 B D (* D (* (* : Motivation Test of factorization in heavy-heavy decays c b B d D + d c D d c D + d f D Decay constant from leptonic decays b B d c D d Form factor from semileptonic decays Size of final-state interactions? Without FSI, factorization predicts B (B D ( * D ( * = Phys. Lett. B 458, 375 (1999 Size of W exchange contribution? (see below Relevant for CKM constraints: Measurement of γ when combined with B D s * + D* sin(β extraction from B D* + D* Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 3

4 B D (* D (* (* : Results [] 11/fb, 3x1 6 BB pairs Mode Branching Fraction / 1 4 B D D <.59 [9% C.L.].3. B D* D B D* D* L log L( max Prediction hep-ph/5795 NEW <.9 [9% C.L.].6. NEW <.9 [9% C.L.].7. NEW B D + D B D* + D B D* + D* B D D B D* D B D D* B D* D*.81 ±.43 ± ±.64 ± ±.57 ± ±.57 ± ±.5 ± ± 1.3 ± ± 1.17 ± NEW* update* update* NEW* NEW* NEW NEW stat. syst. *previously measured by Belle Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 4

5 W Exchange Decays B D (* s + D (* s - 11/fb, 3x1 6 BB pairs highly suppressed in SM sensitive to new physics provides estimates of W-exchange contribution to B D + D - Phys. Lett. B584, 81 (4 W X Predictions: Results (9% C.L. hep-ph/3843 hep-ph/5131 Phys.Rev.D7,11111(5 [Belle (hep-ex/584: B(B D s- D s+ <. x 1-4 ] Reaching sensitivity to test SM prediction Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 5

6 Events / MeV Annihilation Decays B D (* S ϕ Events / MeV Standard Model B : (3..7 x 1-7 1/fb, 34x1 6 BB pairs Could be enhanced by New Physics W Previous CLEO limit: BR(B - D s - φ < 3 x 1-4 BR(B - D* s- φ < 4 x 1-4 Phys. Lett. B319, 365 (1993 X B - D s- φ 6 (a m ES 3 (b (GeV ES m (GeV ES m B - D* s- φ BR< 1.9 x 1-6 [9% C.L.] BR< 1. x 1-5 [9% C.L.] Two orders of magnitude improved; one order of magnitude from SM Sensitivity to New Physics: Competitive limits on parameters in the type II Two-Higgs-Doublet model and the MSSM with R-parity violation. Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 6

7 Charm Production in Recoil: Method Fully reconstruct one B B flavor tag momentum contraint Reconstruct charm hadron from remaining tracks : small combinatorics charge and momentum RECOIL Count charm particles on the recoil side + measure momentum in the parent B rest frame. Distinguish a anticorrelated (b cx and correlated (b cx production b charged and neutral parent B Update of earlier result with more statistics and improved methods /(.15 GeV/c BR (a B D * pc X / correlated (GeV/c / anticorrelated (GeV/c Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 7 /(.15 GeV/c BR * pc - (b B D X

8 Charm Production in Recoil: Results [] 1/fb, 31x1 6 BB pairs prediction 97 hep-ph/1158 prediction 4 ± 5 % First (3.5σ evidence for inclusive correlated D s production; N c agrees with expectation. Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 8

9 Testing Factorization with B D * ωπ (GeV - 1 dγ(b D * ωπ Γ(B D * lν dm X W + ωπ + W W + ωπν B D * τb ν τ D * τ data B D * ωπ CLEO (b /fb, 3x1 l + 6 BB pairs m X (GeV In agreement with predictions based on factorization and τ decays Also: Γ L /Γ=.654 ±.4 ±.16 (from D* angular analysis consistent with predictions (factorization, HQET and semi-lept. B decays Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 9

10 Events / ( 4 MeV/c B Λ c p [with Λ c pk - π + ] m ES (GeV/c m ES Events / ( 8 MeV 5. ±8.4 signal events Baryonic B Decays 11/fb, 3x1 6 BB pairs N bkg N sig E = 459 ± = 5. ± E (GeV Events / ( 4.75 MeV/c B Λpπ m ES m ES (GeV/c 11/fb, 3x1 6 BB pairs E (GeV signal events -11. B= = (3.3 ±.53 ±.31 x 1-6 Consistent with earlier Belle result* Events / ( MeV E B=(.15 ±.36 ±.13 ±.56 x 1-5 stat. syst. B (Λ c pkπ [Λ c pk - π + BF from PDG: (5. ± 1.3%] Consistent with earlier Belle result*; precision significantly improved *Phys. Lett. B617, 141 (5 6 5 splot Events / (.386 GeV/c m Λp near-threshold enhancement *Phys. Rev. D71, 77 ( (GeV/c Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 1 m Λp as observed in other baryonic B decays

11 Charmless B Decays Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 11

12 b qqs Penguin Decays b ccs φ K η K f K S π K S π π K S sin(β eff /sin(φ e 1ff HFAG Moriond 6 PRELIMINARY World Average.69 ±.3 Average.47 ±.19 Average.5 ±.9 Average.75 ±.4 Average.31 ±.6 Average -.84 ±.71 S:= difference in sin(β from b ccs and b qqs penguin Large S would indicate new physics. ω K S ρ K S K + K - K Average.63 ±.3 Average.17 ±.58 Average.51 ± NB: Standard Model corrections ( pollution K S K S K S Average.61 ± new result, cf. J. Ocariz s presentation at Moriond EW Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 1

13 Constraining SM Pollution (I Constrain subdominant (V ub contributions to B φκ via SU(3 relations to obtain SM bound on S φκ Phys. Rev. D 68, 154 (3 Measurements or limits exist for all 11 BF except K* K 8/fb, 3x1 6 BB pairs Search for B K* K s (first time! B(B K* K + B(B K* K < 9% C.L. SU(3 upper bound in S φκ :.43 11/fb, 3x1 6 BB pairs Search for B φπ (update B(B φπ 9% C.L. [B(B + φπ + 9% C.L.] Consistent with theoretical expectations NB: interesting measurements in their own rights! Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 13

14 Constraining SM Pollution (II 11/fb, 3x1 6 BB pairs Similar for B η K s : Events / bin B η ηππ π data signal MC (arbitrary scale background MC sig.+bgrnd. MC Likelihood ratio Results (@ 9% C.L. B(B η π < 1.3x1-6 B(B η π <.1x1-6 B(B η η < 1.7x1-6 Estimated % reduction in theoretical uncertainty on S η KS Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 14

15 Avoiding SM Pollution: B K s K s K L Pure b sss penguin transition V ub SM pollution only via rescattering CP eigenstate no dilution of CP asymmetry 11/fb, 3x1 6 BB pairs Events / (.6 GeV E - ln (L/L NLL scan E (GeV BR( B(B K s K s K L = (.4 ±.6x1-6 9% C.L. (limit for uniform Dalitz distribution; extreme choice 14x1-6 No significant evidence Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 15

16 Search for B η ρ/ B ρ/k* Events / (.5 GeV Events / (. GeV - ln (L/L * η ηππ K* 16 η K 14 ηππ E (GeV 18 * 16 η K ηππ 14 ηππ K* (GeV m ES Β + η K* + E m ES NLL scan Decay mode Theoretical predictions e.g. SU(3 flavour QCD fact. B η K B + η K B η ρ B + η ρ B η f ( π + π Phys.Rev.D69, 341(4 Nucl. Phys. B675,333(3 11/fb, 3x1 6 BB pairs New results 3.8 ± 1.1 ±.5 (4.5 σ ±.8 (3.6 σ < (.3 σ < (.3 σ < (. σ < 1.5 Observation of B η K*, evidence for B + η K* + ; significantly improved limits for the other modes - ln (L/L *+ -6 BR(B η K (1 9 Β η K* * -6 BR(B η K (1 NLL scan Decay mode B(1 6 Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 16 η B η K 3.8 ± 1.1 ±.5 (4.5 σ B ηk 18.7 ± 1.7 K B + η K ±.8 (3.6 σ B+ ηk B η K 63. ± 3.3 B ηk < 1.9 K B + η K ±.7 B + ηk +.5 ±.3 η

17 Conclusion Rare hadronic B decays continue to be a rich and active field of research and provide essential information on the details of hadronic interactions. We keep looking for the needle in the haystack which could turn into a key to physics beyond the Standard Model. Rare Hadronic B Decays J. Kroseberg ( Moriond QCD, March 19 '6 17