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Recent Results on B decays

Recent Results on B decays. - Rare B Decay Highlights + Belle b  sqq Time-dependent CPV -. -. Y.Sakai (Belle/KEK). Outline. Introduction KEKB and Belle Detector [PEP-II/BaBar: by Giorgi] New Results on Rare decays (Belle/BaBar) (Highlights)

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Recent Results on B decays

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  1. Recent Results on B decays - Rare B Decay Highlights + Belle b sqq Time-dependent CPV - - Y.Sakai (Belle/KEK) ICHEP 2004, Beijing

  2. Outline • Introduction • KEKB and Belle Detector [PEP-II/BaBar: by Giorgi] • New Results on Rare decays (Belle/BaBar) • (Highlights) • Updated/New results on b  s TCPV from Belle [Results are preliminary unless references are given] Apology; cannot cover all of the many interesting results from the parallel sessions Contributed papers available Belle: http://belle.kek.jp/conferences/ICHEP2004/ BaBar: http://www.slac.stanford.edu/BFROOT/ www/Public/ichep2004/ ICHEP 2004, Beijing

  3. * VudVub 2(a) * Vtd Vtb 3(g) 1(b) Vcd Vcb * B Decays & the SM Quark level Electro-weak Hadrons QCD/Lattice New Resonances Final state b-quark: Heavy  variety of decay modes Rich field for fundamental SM parameters ICHEP 2004, Beijing

  4. b b W t x s,d s,d g,g,Z B decays & New Physics Experimental measurements agree? SM predictions Yes No Deeper understanding New Physics ? Key point: ANP ~ ASM (small/forbidden) Penguin + New particle, Phase ICHEP 2004, Beijing

  5. Mt. Tsukuba KEKB Belle ~1 km in diameter KEKB Collider 8 GeV e- x 3.5 GeV e+ 11mrad crossing Lpeak = 1.39 x 1034 sec-1cm-2 @ 1.2A x 1.6A - 274M BB 253 fb-1 on Y(4S) 28 fb-1 below Y(4S) ~287 fb-1 ICHEP 2004, Beijing

  6. Continuous Injection No need to stop run Always at ~max. currents, luminosity [CERN courier Jan/Feb 2004] both KEKB & PEP-II ~30% more ∫L dt continuous injection (new) normal injection (old) HER current LER current Luminosity ~1 fb-1/day ! (~1x106 BB) - 0 12 24 Time ICHEP 2004, Beijing

  7. Belle Detector Aerogel Cherenkov cnt. n=1.015~1.030 SC solenoid 1.5T 3.5 GeVe+ CsI(Tl) 16X0 TOF conter 8 GeVe- Central Drift Chamber small cell +He/C2H5 Si vtx. det. 3(4) lyr. DSSD m / KL detection 14/15 lyr. RPC+Fe ICHEP 2004, Beijing

  8. SVD1 SVD2 SVD Upgrade 2003 summer Impact parameter resolution rf Z • 1 MRad >20 MRad • 3 layers 4 layers • 23º<q<139º 17º<q<150º • Rbp = 2.0 cm 1.5 cm • Better I.P. resolutions _ _ 152M BB pairs with SVD1 + 122M BB pairs with SVD2 ICHEP 2004, Beijing

  9. B-meson Reconstruction Utilize special Kinematics at Y(4S) Energy difference: Beam-constrained mass: (ES) ICHEP 2004, Beijing

  10. qq e- e+ Other B continuum Y (4S) e+ e- - BB Signal B Continuum Suppression Dominant Background for rare decays: Continuum e+e-→qq “continuum” (~3x BB) Jet-like To suppress: use event shape variables BB spherical ICHEP 2004, Beijing

  11. W _ _ s/d Vtb t K/p+ W u s/d g K/p+ u u Vub 0 d B _ _ G(Bf ) - G(Bf ) p- p- d d u d d _ _ G(Bf ) + G(Bf ) ACP = 0 d B b b Vus/d Vts/d   B Kp/pp Tree Penguin • Simplest charmless rare decay modes • Tree - Penguin interference Direct CP Violation Key prediction of Kobayashi-Maskawa model Understanding of Penguin Anomaly (New Physics) ICHEP 2004, Beijing

  12. 274M BB New ACP(B0 K+p-) _ B0 K-p+ B0 K+p- Signal: 2139 53 [submitted to PRL] ACP = -0.101  0.025  0.005 3.9ssignificance [PID efficiency bias correction: dA = -0.01  0.004] 2ndEvidence for DCPV at Belle ! [A(p+p-) 3.2s] ICHEP 2004, Beijing

  13. 152M BB App Spp B0gp+p CPV Result Direct CPV 3.2s good tag Dt (ps) App = +0.58 0.15(stat) 0.07(syst) Spp = 1.00 0.21(stat) 0.07(syst) [PRL93,021801 (2004)] ICHEP 2004, Beijing

  14. 274M BB New ACP(B  K+p0 ) Kp0 : 728 53 ACP(Kp0) = 0.04  0.05  0.02 hint thatACP(K+p- ) ¹ACP(Kp0 ) ? (2.4s) [also seen by BaBar] d p0 Large EW penguin (Z0) ? New Physics ? _ d B- b s K- u u ICHEP 2004, Beijing

  15. 274M BB, New Observation of B0p0p0 Key mode for f2(a) in Bgpp CPV isospin analysis Evidence (LP03)Observation ! Signal: 82  16 (6.0s) B = (2.32  ) x 10-6 0.41 0.48 0.22 0.18 Large Br established Mbc [Belle-conf-0406] ACP = 0.43  0.51  0.17 0.16 uses same Flavor-tagging as TCPV analysis 1st measurement ! BaBar results & f2(a)  Giorgi’s talk ICHEP 2004, Beijing

  16. 224M BB B0KK B0K0K0 Nsig = 23 2.0 (4.5s) 7.7 6.7 0.40 0.35 B = (1.19  0.13) x 10-6 “pure b  d Penguin” B0K0K+ Nsig = 41 143 (3.5s) B = (1.46 0.50 0.07) (<2.35) x 10-6 First signals for B0KK ICHEP 2004, Beijing

  17. t s Penguin Anomaly ? New physics effect ? fK*(bsss) only ? - b W Vts  Vtb s f s g K*0 d s + u B r+ K*+ d u u u B  VV : Polarization Puzzle Naïve Factorization : Longitudinal fL = 1 – O(1/mb2) r+r-, r+r0,(r0K*+): fL» 1 (BaBar/Belle) Tree dominated fL(fK*) ~ 0.5 Penguin only QCD penguin annihilation: O(1/mb2) O(1) f^/ f// = 1 + O(1/mb) ? fL(r+K*0) < fL(fK*) ? [r+K*0: pure bs Penguin] [e.g. A.Kagan hep-ph/0405134] ICHEP 2004, Beijing

  18. - 152M BB B  r+K*0 Polarization Mbc DE r+,K*0 mass region 2D(Mbc,DE,) ML fit peak: 6.3s signif. Mbc, DE signal region simultaneous fit to r,K* masses K*0mass r+mass r+K*0 : 26.6 8.7 (Stat. sig: 3.2s) [Belle-conf-0404] ICHEP 2004, Beijing

  19. - 152M BB B  r+K*0 Polarization K*0 helicity r+ helicity bkg (fixed) r+Kp(fixed) Transverse Longitudinal 2D(r,K* helicity) ML-fit (Mbc, DE, mass signal region) 0.05 0.07 fL =0.50  0.19  (3.1s away from fL= 1 ) B = (6.6  2.2  0.8 ) x 10-6 [Belle-conf-0404] ICHEP 2004, Beijing

  20. - 89M BB B  r+K*0 Polarization [BaBar-conf-04/34] ML fit to all distributions simultaneously 1st observation 23 24 Nsig = 141  (>5s) fL =0.79  0.08 0.040.02 0.0 1.9 B = (17.0  2.9  2.9  ) x 10-6 ACP = -0.14  0.17 0.04 non-resonant contribution BaBar + Belle likely fL < 1 ICHEP 2004, Beijing

  21. Bf K* : New Physics Search Transversity basis: Angular distribution PfK*( qtr, ftr, qK*; A0, A//, A^) A0 : longitudinal (CP= +1) A// : transverse CP= +1 A^ : transverse CP= -1 2 sets _ (B, B) (12-1 parameters) __ Lll = fl= (|Al|2+ |Al|2)/2,Sll = (|Al|2- |Al|2)/2 Direct CPV _ _ _ _ S^i = -Im(A^Ai*+A^Ai*), L^i = -Im(A^Ai*-A^Ai*) Triple-prod. (T-violation) _ _ _ _ L//0 = Re(A//A0*+A//A0*), S//0 = Re(A//A0*-A//A0*) (i = 0, //) ( |A0|2+ |A//|2 + |A^|2 =1 ) “¹0”  NP [e.g. London, Sinha2, PRD69,114013(04)] ICHEP 2004, Beijing

  22. - 152M BB B f K* [Belle-conf-0419] f K*0 97  signals 12 11 fL =0.51  0.06 0.04 confirm low fL f K*+ 46  signals 9 8 ICHEP 2004, Beijing

  23. - 152M BB Bf K* : New Physics Search f^/ f// ~ 1 FSI Triple product (T-conserving) “¹0”  NP Triple product (T-violating) [Belle-conf-0419] ICHEP 2004, Beijing

  24. Bf K* : New Physics Summary arg(A// /A0 ) 2.34 0.23 0.05 (-2.34) -2.21 0.22 0.05 arg(A^ /A0 ) 2.47 0.25 0.05 (0.67) 0.64 0.21 0.06 BaBar (227M) Belle (152M) BaBar/Belle consistent * “¹0”  NP * No indication of NP except fL puzzle (* recalculated from fit values) ICHEP 2004, Beijing

  25. aEW Radiative & EW Penguins Loops Sensitive to New Physics l+ l- b  sl+l- penguin ~1/100 b  sg penguin Br, ACP ~SM b  dg penguin K*g TCPV ICHEP 2004, Beijing

  26. 274M BB B → K(*) l+l- [Belle-conf-0415] LP03: B Xsll, K(*)ll : Belle/BaBar Br, ACP ~SM update >10s signals 82 11 signals 79 10 signals B (Kll)= (5.50 0.27  0.02) 0.75 0.70 B (K*ll)= (16.5  0.9  0.4) 2.3 2.2 x 10-7 ICHEP 2004, Beijing

  27. 274M BB K* B → K* l+l- :FB Asymmetry AFB(K*ll ) : very sensitive to NP that may not be seen in B(bsg) raw AFB q2 First Look ! q2 [Belle-conf-0415] ICHEP 2004, Beijing

  28. 274M BB 219M BB b → dg : B → (r,w)g [Belle-conf-0401] Suppress K*g with PID and M(‘K’p) cut B(B(r,w)g) = (0.72 0.27 )x 10-6 (1.9s) [< 1.4 x 10-6 @90% CL] +0.43 -0.39 Simultaneous fit to 3 modes: G(B(r,w)g) = G(B+r+g) = 2G(B0r0g) = 2G(B0wg) B(B(r,w)g) = (0.6 0.3 0.1) x 10-6 (2.1s) [< 1.2 x 10-6 @90% CL] |Vtd|/|Vts| [ A.Ali’s talk] [hep-ex/0408034] ICHEP 2004, Beijing

  29. b  sqq Penguin CPV - Belle @LP03 (140 fb-1) [PRL 91, 261602 (2003)] B0fKs B0 J/yKsetc sin2f1=0.728  0.06 “sin2f1”= -0.96  0.51 3.5s deviation from the SM ! ICHEP 2004, Beijing

  30. * V V tb ts Time-dependent CP Violation (TCPV) B0 ｆｃｐ ｆｃｐ = B0 mixing B0 B0 ACP (Dt) = S sin(DmDt) + A cos (DmDt) Mixing induced CPV Direct CPV f + SM: bs Penguin phase = J/yKS(bc) + New Physics with New Phase Sbs¹ sin2f1 , Acan¹ 0 Sbs=sin2f1, A=0 ICHEP 2004, Beijing

  31. 274M BB pB* B0f K0 fKS Nsig=139 14 fKL purity 0.63 Nsig= 36 15 purity 0.17 Similar to J/yKL recon. + sophisticated continuum suppression includes Ks p0po (Nsig=13 5) ICHEP 2004, Beijing

  32. 274M BB S = 0.736 fit B0f K0 : CPV Result f K0 Good tags Poor tags Good tags fKS+fKL:S(fK0) = +0.06 ±0.33 ±0.09 A(fK0) = +0.08 ±0.22 ±0.09 ~2.2s away from SM ICHEP 2004, Beijing

  33. Checks: sin2f1 (B0J/y KS/L) Validation of new data sample (SVD2) _ SVD1: 152M BB SVD1 S = 0.696  0.061 (stat) A = 0.011  0.043 (stat) Good tags _ SVD2: 122M BB SVD2 S = 0.629  0.069 (stat) A = 0.035  0.044 (stat) Good tags Dt (ps) f K0 ~2.3s SVD1: S = -0.68  0.46 A = -0.02  0.28 SVD2: S = +0.78  0.45 A =+0.17  0.33 many systematic checks, all ok  ICHEP 2004, Beijing

  34. 274M BB S = 0.736 fit B0h’KS& K+K-KS high statistics modes h’KS K+K-KS (fexcluded) h’rg, hp+p- (hgg, p+p-p0) Nsig=399 28 Nsig=512 27 purity 0.56 purity 0.61 CP=+1: 1.03 0.15 0.05 Raw Asymmetry Raw Asymmetry Good tags Good tags “sin2f1” (~0.5s @SM) (~1.0s @SM) S = +0.65 0.18 0.04 -S = +0.490.18 0.04 ( ) A = -0.19 0.11 0.05 A = -0.08 0.12 0.07 0.17 0.0 ICHEP 2004, Beijing

  35. 274M BB S = 0.736 fit B0wKS& f0(980)KS wKS f0(980)KS additional modes Nsig=31 7 Nsig=102 18 purity 0.58 purity 0.56 Raw Asymmetry Raw Asymmetry Good tags Good tags “sin2f1” (~0s @SM) (~2.9s @SM) S = +0.75 0.64 -S = -0.470.41 0.08 A = +0.26 0.48 0.15 A = -0.39 0.27 0.08 0.13 0.16 ICHEP 2004, Beijing

  36. 274M BB p+ p- Ks track S = 0.736 fit B vertex IP profile g g B0 Ksp0 Ksp0 Vertexing by Ks only Nsig=168 18 purity 0.55 (+low purity: Nsig=83(0.17)) Validated by J/y Ks (use Ks only) (~0.7s @SM) “sin2f1” Raw Asymmetry S = +0.30 0.59 0.11 A = -0.12 0.20 0.07 Good tags ICHEP 2004, Beijing

  37. 274M BB Summary of b  sqq CPV - “sin2f1” 2.4 (A: consistent with 0) ICHEP 2004, Beijing

  38. Ks track p+ p- g g B vertex IP profile g B  K*g TCPV: New Physics SM: g» polarized B0&B0 opposite S ≈ 2(ms/mb)sin 2f1 ≈ 4% A ~ 1% - New Physics  Large S, A [e.g. Atwood,Gronau,Soni] B0  K*[Ksp0]g Analysis Technique: similar to B0 Ksp0 ICHEP 2004, Beijing

  39. 274M BB - 124M BB B  K*[Ksp0]g TCPV [hep-ex/0405082] Nsig=57 9 purity 0.65 S = 0 fit Nsig=105 14 S = +0.250.63 0.14 S = -0.79 0.09 A = +0.57 0.32 0.09 = -C A = -0.00 0.38 0.63 0.50 First step for new era of b  sg ! ICHEP 2004, Beijing

  40. Summary B decays: many new results from BaBar/Belle - Evidence for Direct CPV, ACP(K+p-) ¹ACP(K+p0) ? - B p0p0 decay established, 1st measurement of ACP(p0p0) -fL(fK*)Polarization Puzzle: fL(r+K*0) < 1 No hint of T-violating NP in BfK* - A first look at B  K*ll FB-asymmetry - 1stB0  K*[Ksp0]g TCPV measurements - Belle b sqq TCPV updates - S(fK0) = +0.06 ±0.33 ±0.09 (~2.2s away from SM) - average of b  sqq:+0.43 ±(~2.4s from SM) - 0.13 0.11 (Giorgi’s review for BaBar results) More data needed to conclusively establish New Physics ICHEP 2004, Beijing

  41. Charmless B Br Summary HFAG P.Chang (NTU) J.Alexander (Cornell) J.Smith (Colorado) Complete list (other Br &ACP) http://www.slac.stanford.edu/xorg/hfag/rare/ x10-6 ICHEP 2004, Beijing

  42. Backup ICHEP 2004, Beijing

  43. B PP/PV/VV Summary r-r0w fK*- K*0 p-p0h h’ K- K0 p+ p0 h h’ K+ K0 observed (>5s) r+ r0 w f K*+ K*0 evidence (>3s) upper limit Both, BaBar, Belle, CLEO DCPV: evidence in p+p-/K+p- only [extend to decays into scalar, axial-vector] ICHEP 2004, Beijing

  44. B0f KS : Mass & Helicity f Helicity Mass bkg ICHEP 2004, Beijing

  45. B0f K0 : SVD1,2 SVD1 only SVD2 only ~2.3s SVD1: S = -0.68  0.46 A = -0.02  0.28 SVD2: S = +0.78  0.45 A =+0.17  0.33 many systematic checks, all ok  ICHEP 2004, Beijing

  46. B0f KS, f KL : CPV fKL only fKSonly S = +0.00 ±0.33 A = +0.06 ±0.22 −S= +2.3 ±2.0 A = +0.6 ±1.2 ICHEP 2004, Beijing

  47. B0f K : Validations Control sample Lifetime fit w/ B →fK±/KS Asymmetry fit w/ fK± B →fK± B →fKS S(fK±) = –0.03 ±0.20 A(fK±) = +0.22 ±0.15 +0.20 –0.19 +0.12 –0.11 tB+= 1.67 tB0= 1.59 ICHEP 2004, Beijing

  48. Systematic errors on S KKKS: effective sin2f1 0.17 for CP-even fraction ICHEP 2004, Beijing

  49. SVD2: lifetime & Dmd SVD2 only D0p+, J/yK , D–p+, D*–p+/r+, D*ln Belle preliminary SVD1 _ (152M BB) SVD2 _ (122M BB) (stat) [ps] (stat) [ps] (stat) [ps-1] [Belle-conf-0436] New detector resolution is well understood ICHEP 2004, Beijing

  50. - History of b  sqq CPV ICHEP 2004, Beijing

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