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B K p and photon spectrum at Belle Heyoung Yang Seoul National University for Belle Collaboration ICHEP2004
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H.Y.G.YangICHEP2004-08-172 Introduction to b s(d) FCNC process forbidden at tree level in SM sensitive to New Physics B-factory experiments best experiment to measure FCNC e+e - collider experiment - good background suppresion with high Luminosity
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H.Y.G.YangICHEP2004-08-173 Results on FCNC at Belle b s First observation of B K 1 First observation of B First observation of p photon spectrum b d Search for B
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H.Y.G.YangICHEP2004-08-174 b s(d) analysis tool Kinematic constraints E = E * B ― E * beam Mbc= (E * beam ) 2 ― |P * B | 2 Continuum suppression with event shape parameters B flight angle (cos B ) Fisher discriminant Particle ID with ACC/TOF/CDC EE Mbc cos B Fisher
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First Observation of B K 1 with 140/fb
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H.Y.G.YangICHEP2004-08-176 BK1BK1 Known exclusive 2-body decay of b s process B K*(892) (K*(892) K ) B K 2 *(1430) (K 2 *(1430) K ) Possible 2-body decays : B K 1 K 1 axial vectors, mixing states of K 1A & K 1B K 1 (1270) = K 1A cos + K 1B sin K 1 (1400) = K 1A cos – K 1B sin
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H.Y.G.YangICHEP2004-08-177 BK1BK1 Theoritical predictions (e.g) S.Veseli and M.G.Olsson PLB 367, 309(1996) B [B K 1 (1270) =(1.20 0.44) 10 -5 B [B K 1 (1400) =(0.58 0.26) 10 -5 H.Y.Cheng and C.K.Chua PRD 69, 094007(2004) sensitive to their mixing angle B [B K 1 (1270) =(0.77 0.11) 10 -5 (or (0.02 0.02) 10 -5 ) B [B K 1 (1400) =(0.08 0.04) 10 -5 (or (0.80 0.12) 10 -5 )
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H.Y.G.YangICHEP2004-08-178 Inclusive B K B [B + K + by Belle, 29.1/fb PRL 89(2002) Reanalysis for / Ks 0 with 140/fb 318.2 22 B + K + 67.4 9 B 0 K 0 B [B + K + ] = (2.50 0.18 0.22) 10 -5 20.4 B [B 0 K 0 ] = (2.43 0.36 0.34) 10 -5 10.9 First Observation
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H.Y.G.YangICHEP2004-08-179 BK1BK1 MK distribution for the search of K 1 (1270) or K 1 (1400) K 1 (1270) K (42%) / K 1 (1400) K (3%) 0.6<M <0.8GeV K 1 (1270) K (16%) / K 1 (1400) K (94%) 0.8<MK <1.0GeV 2D Unbinned fitting with Mbc & MK M bc MK M bc MK K 1 (1270) K 1 (1400) Total K 2 *(1430) NR + b2s,K* feed continuum+BBbar K 1 signals 0.6<M <0.8GeV0.8<MK <1.0GeV 101.6 22 K 1 (1270)22.7 26 K 1 (1400)
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H.Y.G.YangICHEP2004-08-1710 BK1BK1 B [B + K 1 (1270) + ] = (4.28 0.94 0.43) 10 -5 9.2 B [B + K 1 (1400) + ] < 1.44 10 -5 @ 90% CL 1.3 (1.0<MK <2.0 GeV ) First Observation
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First Observation of B with 140/fb
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H.Y.G.YangICHEP2004-08-1712 B K s can be used for the time-dependent CP asymmetry study Event reconstruction as + (Ks 0 ) 45.0 11.0 B K B [B K ] = (6.9 +1.7 +1.3 -1.6 -1.0 ) 10 -6 5.0 First Observation (MK <2.4 GeV)
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H.Y.G.YangICHEP2004-08-1713 B MK distribution for possible resonance Enhancement around MK GeV but not significant K 3 *(1780) ? 1.6<MK <1.95 GeV B [B K 3 *(1780) ] < 34 10 -6 @ 90% CL
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First Observation of B p with 140/fb
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H.Y.G.YangICHEP2004-08-1715 B p Radiative baryonic B decay, B p / B p 2D unbinned fitting with E & M bc 34.1 7 B + p Theoretical prediction: Theoretical prediction: * Pole Model * Pole Model : Phys.Lett. B533 (2002) B (B p Λ ) ~ 1.2x10 -6 B (B pΣ 0 ) ~ 2.9x10 -9 *QCD counting rules *QCD counting rules : (hep-ph/0405 283) B (B pΛ ) ~ (1.2-2.4)x10 -7 B (B pΣ 0 ) ~ (2.8-6.5)x10 -7
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H.Y.G.YangICHEP2004-08-1716 B p B [B + p ] = (2.16 +0.58 -0.53 0.20) 10 -6 8.6 B [B 0 p ] <3.3 10 -6 @ 90% CL p GeV/c 2 for p (Mp 4.0 GeV/c 2 for p Details will be covered by M.-Z.Wang at next talk. First Observation
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Photon spectrum of b s with 140/fb
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H.Y.G.YangICHEP2004-08-1718 Photon spectrum of b s Full inclusive reconstruction for only E spectrum Measure E of highest mementum photon veto photons from 0 and apply event shape cuts to suppress continuum b.g. cut optimized by using 15/fb off-resonance data Photon energy spectrum measurements: CLEO : 9/fb, E > 2.0 GeV Babar : 54/fb, E > 2.1 GeV new result from Belle : 140/fb, E > 1.8 GeV
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H.Y.G.YangICHEP2004-08-1719 Photon spectrum of b s X s ] = (3.55 0.32 ) 10 -4 = 2.292 0.026 0.034 GeV - 2 = 0.0305 0.0074 0.0063 GeV 2 Data After subtraction and efficiency correction +0.30 +0.11 -0.31 -0.07 PRL93,061803(2004)
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Search for B with 253/fb
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H.Y.G.YangICHEP2004-08-1721 Search for B b d suppressed in SM by |V td /V ts | 2 |V td /V ts | 2 by B (B )/ B (B K* ) large direct CP violation is predicted in b d Ali and Parkhomenko, Eur.Phys.J. C23 (2002) 89-112 Bosch and Buchalla, Nucl.Phys. B621 (2002) 459-478
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H.Y.G.YangICHEP2004-08-1722 Search for B Event reconstruction ( ) / ( ) / ( ) with special continuum suppression Fisher & cos B & z of B-vertex LR(Likelihood Ratio) 2D optimization with LR & QR(Quality of flavor tag) LR QR signal continuum
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H.Y.G.YangICHEP2004-08-1723 Search for B B K* suppression by MK cut suppression by helicity cut BG signal
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H.Y.G.YangICHEP2004-08-1724 Search for B with 253/fb For check of analysis method using B K*(892) study B [B K*(892) ] = (37.2 1.8) 10 -6 good agreement with World Average
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H.Y.G.YangICHEP2004-08-1725 Search for B with 253/fb Total significance 1.9 Simultaneous unbinned fitting for assuming their isospin relations
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H.Y.G.YangICHEP2004-08-1726 Search for B with 253/fb B [B ( ] < 1.4 10 -6 B [B + ] < 2.2 10 -6 B [B 0 ] < 0.8 10 -6 B [B ] < 0.8 10 -6 B [B ( ] / B [B K* ] = 0.019 +0.012 -0.010 0.007 < 0.035 |V td /V ts | =0.16 0.05 0.02(th) < 0.22 @ 90% CL ( Form factor : Ali (2004) : 0.85 0.10 is used )
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H.Y.G.YangICHEP2004-08-1727 Summary First observations of B + K 1 (1270) + / inclusive B 0 K 0 B p Upper limits of B + K 1 (1400) + B K 3 *(1780) B 0 p B / B |V td /V ts | Measured photon spectrum of b s
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