Hadronic B Decays at BELLE and BABAR Sheng-Wen Lin National Taiwan University B →K,  and KK Ratios of Branching Fractions Observation of B+ →K+K0 and B0 →K0K0 ACP of K+-, K+0 and +0 B+ →ρ+K0 B0→ρ0ρ0 B0→ K* B0→a0-π+ and a0-K+ Conclusion 2007/3/18

Puzzle of K Within the SM: Rc-Rn≈0, Acp(K+π-) - Acp(K+π0)≈0 Buras, Fleischer et al, APO B36(2005)2015-2050 Within the SM: Rc-Rn≈0, Acp(K+π-) - Acp(K+π0)≈0 New Physics : B0→π0K0 and B+→π0K+ may have color-allowed EW penguins form Rc and Rn have sizeable effects by EW penguin Described theoretically by q and  q : strength of the EW penguin with respect to the tree contribution : CP-violation phase 2007/3/18

Theory of KK B+ →K0K+ and B0→K0K0 are dominated by b →d penguin B0 → K+ K- is from annihilation diagram J.-M. Gerard and W.-S. Hou, PLB 253, 478 (1991) BF of B+ →K0K+ and B0→K0K0 are of order 10-6 Sizable asymmetry of O(45%) of B0→K0K0 C.-H. Chen and H.-n. Li, PRD 63, 014003(2001) There is no CP asymmetry in the B0→K0K0 mode and small BF for B0 → K+ K- is expected if no strong FSI effect 2007/3/18

K+ - and + - 449M BB 227M BB B→+- B→K+- hep-ex/0609015 B→+- B→K+- Sig(red) Con(dash) rareB(hatched) + -→K+- (dotted) 227M BB PRD 75, 012008 (2007) sPlots Consider the final state radiation effects in these modes 2007/3/18

BF of K+π0,π+π0 and K0π0 449M BB K00 0 K0 0 347M BB K0 K00 hep-ex/0609015 K00 0 K0 0 347M BB K0 hep-ex/0607106 K00 hep-ex/0607096 Simultaneous fit for π+π0 and K+π0 at Belle and BaBar Use MES and Mmiss to extract yield for K0π0 at BaBar 2007/3/18

B→KK: Observation of b → d penguin 449M BB K+K- 347M BB K0π+ 5.3σ K0K+ 5.3σ K0K0 7.3σ 6.0σ hep-ex/0608049(submit to PRL) PRL 97, 171805(2006) 2007/3/18

Summary of B →hh 2007/3/18

2007/3/18

New Electroweak Penguins in the Ratios Rn and Rc q: measures the importance of the EW penguins with respect to the tree-diagram-like topologies : CP-violating weak phase BaBar Belle SM Old WA Data Buras, Fleischer et al, APO B36(2005)2015-2050 2007/3/18

Direct CP Asymmetries(Belle) K+π-: -0.093±0.018±0.008 (4.7σ) K+π0: 0.07±0.03±0.01 (2.3σ) π+π0: 0.07±0.06±0.01 Acp(K+π-) - Acp(K+π0) 4.4σ Preliminary The other decay modes: hep-ex/0608049(submit to PRL) 2007/3/18

Direct CP Asymmetries(BaBar) K+π-: -0.108±0.024±0.007(4.3σ) (2542±67) K+π0: 0.016±0.041±0.010 π+π0: -0.019±0.088±0.014 Acp(K+π-) - Acp(K+π0)  2.6σ 347M BB hep-ex/0607106 Observation of K+π- Direct CP asymmetry: -0.107±0.018+0.007-0.004 (5.5σ) (4372±82) Using dE/dx as a discriminating variable in the M.L. fit |cosθSpher|<0.9→ |cosθSpher|<0.8 Total increase in rec. eff. is 52% 383M BB hep-ex/0703016(submit to PRL) 2007/3/18

BF of B+→ρ+K0 and search for B+→ K*0K+ 383M BB ρ+K0 Pure penguin b→s PV decay Branching Fraction : (8.0 +1.4 -1.3 ±0.5)x10-6 (7.9σ) CP asymmetry: (-12.2±16.6±2.0) % Observation of this mode BF and ACP are consistent with SM hep-ex/0702043 Mπ+π0 cosθρ Dominated by the bdg penguin amplitude bd analogue of B+ρ+K0 (both VP and penguin) ρ+K0 2007/3/18

Evidence for B0→ρ0ρ0 383M BB tree contribution is color-suppressed →decay rate is sensitive to the penguin amplitude Complete the isospin triangle Branching Fraction: B0→ρ0ρ0:1.07±0.33±0.19 x10-6 (3.5σ) Upper limit: B0→ρ0f0(980),f0→π+π-: < 0.53 x 10-6 B0→f0(980)f0(980),f0→π+π-: < 0.16 x 10 -6 longitudinal polarization fraction : 0.87 ±0.13± 0.04 hep-ex/0612020 2007/3/18

B0  K*0 Full amplitude analysis: 384 M BB H2 H1 K*(892) K*(1430) PRL 98: 051801, 2007 H2 H1 K*(892) K*(1430) 2007/3/18

Search for B0→a0-π+and a0-K+ Preliminary a0-π+ a0-K+ a0(1450)-π+ a0(1450)-K+ Evidence taht a0(980) meson is a four-quark state 2007/3/18

Conclusion Kπpuzzle Two ratios: Rn, Rc  Belle : consistent with SM prediction BaBar : also move towards SM prediction Significant difference between Acp(K+π-) and Acp(K+π0) Large colour-suppressed trees Observation of b →d modes and B+→ρ+K0 Only from BaBar Evidence of B0→ρ0ρ0 at BaBar fL~0.5 in BK*, implies |A0|  |A+1| >> |A-1| a0(980) meson like a four-quark state 2007/3/18

Backup 2007/3/18

B signal reconstruction The signal yield are usually extracted by Mbc and ΔE Beam constrained mass : Precise beam energy known from accelerator Lower error on momentum resolution Energy difference : Asymmetry shape and shift due to energy loss Ebeam : run dependent beam energy EB* and PB* are the reconstructed energy and momentum of the B candidates in CM frame 2007/3/18

PHOTOS g Final state radiation (FSR) effects: E. Barberio, Z. Was Comput. Phys. Commun. 79,291 (1994) p- p+ g B0 Final state radiation (FSR) effects: PHOTOS included in our MC for all B→hh modes. Systematic uncertainty of PHOTOS in B→hh now calculated ~ 1/million (negligible for non-SUPERB statistics): PHOTOS v 2.13 Interference on, double photon on, Ecut~26MeV Impact on eff w/o PHOTOS p+p- K+p- h+p0 9.4% 5.8% 3.6% G.Nanava and Z.Was hep-ph/0607019 2007/3/18

Calibration of signal PDF MC Signal MC sample Data The PDF of data and MC are the same ? Control sample Like B- →D0- 2007/3/18

Correction of efficiency PID selection 0 reconstruction efficiency Track reconstruction efficiency KS reconstruction efficiency D*+ →D0+, D0 →K-+ D0→K-+ and D0→K-+0 D*+→D0+,D0→+-KS D+→K-++, D+→KS+ 2007/3/18

2D Ext. Un-binned ML Fit 2007/3/18

Systematics of Br(Bhh) Systematics of FSR is about 1.0% 2007/3/18

Systematics of Acp detector bias of Kπ0,ππ0 from qq bkg in (ΔE, mbc) detector bias of Kπ　from D*+　　D0(Kπ)π+ 2007/3/18

B0 → 00 Time information On time 9000<t<11000 Too late Too early Difficult to model the distribution for off-time QED background with MC Re-process the raw-data for timing information Off-time events ~5.28GeV/c2 Bhabha events 2007/3/18

BF. of B0 →00 hep-ex/0610065 277M BB 535M BB 2007/3/18