Improved measurements of B → hh decays at Belle Sheng-Wen Lin National Taiwan University, Department of Physics Motivation BF of B →K and  Observation of B+ →K+K0 and B0 →K0K0 ACP of K+-, K+0 and +0 B0 →00 Conclusion 2006/11/01

Motivation I Exciting results on ACP in B0 →K+ - and B+→h+0 Large BF of B0 →00 Theoretical predictions for direct CP violation and BFs of B →hh Evidence of B+ →K+K0 and B0→K0K0 Last publication : BF of B → hh (78 fb-1) 449 M BB It is time to update the BFs of B→hh modes 2006/11/01

Theory of K and  PQCD : H.-N. Li and S. Mishima, hep-ph/0602214 NLO : vertex correction, quark loop and magnetic penguin FSI : H.-Y. Cheng, C.-K Chua and K.-C. Yang, PRD 71, 014030 (2005) SD(LD) : short(long) distance correction 2006/11/01

Theory of K and  These three ratios depend weakly on the inputs PQCD : H.-N. Li and S. Mishima, hep-ph/0602214 These three ratios depend weakly on the inputs Buras, Fleischer et al, APO B36(2005)2015-2050 R= 0.943+0.028-0.021 Rn, Rc affected by EW penguins Rc=1.14 0.05 Rn=1.11+0.04-0.05 New Physics? 2006/11/01

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 2006/11/01

Theory of KK Extract the angle 3 from the B →KK branching fractions B+ →K0K+ increases with 3 while BF(B0 → K+ K- ) decreases with 3 There is no CP asymmetry in the B0→K0K0 mode and small BF for B0 → K+ K- is expected if not, exist strong FSI effect C.-H. Chen and H.-n. Li, PRD 63, 014003(2001) K0K+ K0K0 K+K- 2006/11/01

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 2006/11/01

Feeddown Simultaneous Fit K+- K+- sample other +- other +-ample +- fake K+- sample other +- K+- fake other +-ample Decays with simultaneous fit : K+0+0, K+K0+K0 2006/11/01

K+ - and + - hep-ex/0609015 Sig : 2D Smooth histogram Apply ΔE and Mbc calibration corrections Con : Argus(Mbc) X 1st order chebyshev polynomial(ΔE) rareB :2D smooth histogram Feed-across : 2D smooth histogram B→+- B→K+- Sig Con rareB + -→K+- 2006/11/01

h0,K0 0 and 00 0 K0 K00 00 ? 2006/11/01

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 2006/11/01

Observation of K0K+ and K0K0 hep-ex/0608049 KS+ KSK+ 5.7  KSKS K+K- 6.0  2006/11/01

Direct observation of hadronicb→d penguin Summary of B →hh (I) Direct observation of hadronicb→d penguin 2006/11/01

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 New Belle Data w/414 fb-1 SM Old WA Data Buras, Fleischer et al, APO B36(2005)2015-2050 2006/11/01

Summary of B →hh (II) The ratios of the B → K branching fractions 0.850.06 1.000.08 0.820.08 PQCD : H.-N. Li and S. Mishima, hep-ph/0602214 2006/11/01

Analysis with 535 M BB ACP of B0 →K+- and B+ →h+0 BF. and ACP of B0 →00 2006/11/01

Feeddown Single Fit : K+- Simultaneous Fit : K+0+0 K+- BF(+-)/BF(K+-) K+- +- fake K+- sample other Simultaneous Fit : K+0+0 K+0 sample K+0 other +0 fake +0ample other K+0 fake +0 2006/11/01

ACP of B0 →K+- PID has charge asymmetry N( K+- →K-+) N(K-+) PID has charge asymmetry Dilution due to double tracks PID fake B0→K-+ B0→K+- B0→K-+ B0→K+- 2006/11/01

ACP of B+→h+0 B-→K-0 B+→K+0 B-→-0 B+→+0 2006/11/01

Acp (Bhh) Preliminary Significant DCPV in K+π- and π+π- Black 449 MBB Blue 535 MBB Green 535 MBB Time-dep. analysis Preliminary Significant DCPV in K+π- and π+π- Acp(K+π-) - Acp(K+π0)  4.4σ 2006/11/01

B0 →00 hep-ex/0610065 B0 2006/11/01

2006/11/01

Conclusion Improved measurement of B→hh BF Rn, Rc with SM prediction ”K puzzle” is no more Observation of B+→K+K0 and B0→K0K0 Acp(K+π-) - Acp(K+π0)  4.4σ Maybe colour-suppressed trees Maybe New Physics More data is needed to improve the precision of B0→00 result 2006/11/01

Backup 2006/11/01

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 2006/11/01

Calibration of signal PDF MC Signal MC sample Data The PDF of data and MC are the same ? Control sample Like B- →D0- 2006/11/01

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+ 2006/11/01

2D Ext. Un-binned ML Fit 2006/11/01

Systematics of Br(Bhh) Systematics of FSR is about 1.0% 2006/11/01

Systematics of π0π0 Br=1.1±0.3±0.1 2006/11/01

Systematics of Acp detector bias of Kπ0,ππ0 from qq bkg in (ΔE, mbc) detector bias of Kπ　from D*+　　D0(Kπ)π+ 2006/11/01

BF. of B0 →00 hep-ex/0610065 277M BB 535M BB 2006/11/01