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Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Eigen G Ofte I Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Pripstein M Roe NA Ronan MT Tackmann K Wenzel WA del Amo Sanchez P Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Schroeder T Steinke M Boyd JT Burke JP 《Physical review letters》2007,99(5):051801
We have performed a search for the flavor-changing neutral-current decays B-->pil+ l-, where l+ l- is either e+ e- or mu+ mu-, using a sample of 230 x 10(6) Upsilon(4S)-->BB decays collected with the BABAR detector. We observe no evidence of a signal and measure the upper limit on the isospin-averaged branching fraction to be B(B-->pil+ l-)<9.1 x 10(-8) at 90% confidence level. We also search for the lepton-flavor-violating decays B-->pie+/- mu-/+ and measure an upper limit on the isospin-averaged branching fraction of B(B-->pie+/- mu-/+)<9.2 x 10(-8) at 90% confidence level. 相似文献
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Aubert B Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Palano A Pompili A Chen GP Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Clark AR Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF LeClerc C Levi ME Lynch G Oddone PJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Harrison TJ Hawkes CM Knowles DJ O'Neale SW Penny RC Watson AT 《Physical review letters》2002,88(24):241801
We present results from a search for the flavor-changing neutral current decays B-->Kl(+)l(-) and B-->K(*)l(+)l(-), where l(+)l(-) is either an e(+)e(-) or mu(+)mu(-) pair. The data sample comprises 22.7 x 10(6) Upsilon(4S)-->B(-)B decays collected with the BABAR detector at the PEP-II B Factory. We obtain the 90% C.L. upper limits B(B-->Kl(+)l(-))<0.51 x 10(-6) and B(B-->K(*)l(+)l(-))<3.1 x 10(-6), close to standard model predictions for these branching fractions. We have also obtained limits on the lepton-family-violating decays B-->Ke+/-mu(-/+) and B-->K(*)e(+/-)mu(-/+). 相似文献
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Burdman G 《Physical review D: Particles and fields》1995,52(11):6400-6410
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Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G LeClerc C Lynch G Merchant AM Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Wenzel WA Ford K Harrison TJ Hawkes CM 《Physical review letters》2004,93(8):081802
We measure the branching fraction for the flavor-changing neutral-current process B-->X(s)l(+)l(-) with a sample of 89x10(6) Upsilon(4S)-->BBmacr; events recorded with the BABAR detector at the PEP-II e(+)e(-) storage ring. The final state is reconstructed from e(+)e(-) or micro(+)micro(-) pairs and a hadronic system X(s) consisting of one K+/- or K(0)(S) and up to two pions, with at most one pi(0). We observe a signal of 40+/-10(stat)+/-2(syst) events and extract the inclusive branching fraction B(B-->X(s)l(+)l(-))=(5.6+/-1.5(stat)+/-0.6(exp syst)+/-1.1(model syst))x10(-6) for ml(+)(l(-))>0.2 GeV/c(2). 相似文献
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Aubert B Barate R Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF Kukartsev G LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Ford K 《Physical review letters》2004,92(14):141801
We present a study of the decay B--->D(*0)K(*-) based on a sample of 86 x 10(6) Upsilon(4S)-->BBmacr; decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure the branching fraction B(B--->D(*0)K(*-))=(8.3+/-1.1(stat)+/-1.0(syst)) x 10(-4), and the fraction of longitudinal polarization in this decay to be Gamma(L)/Gamma=0.86+/-0.06(stat)+/-0.03(syst). 相似文献
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Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Telnov AV Wenzel WA Ford K Harrison TJ Hawkes CM 《Physical review letters》2004,92(12):121801
A search for the lepton-flavor-violating decay of the tau into three charged leptons has been performed using 91.5 fb(-1) of data collected at an e(+)e(-)center-of-mass energy around 10.58 GeV with the BABAR detector at the SLAC storage ring PEP-II. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (1-3)x10(-7) at 90% confidence level. 相似文献
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Kaneko J Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bartel W Bay A Behera PK Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi Y Choi YK Danilov M Dong LY Eidelman S Eiges V Enari Y Everton CW Fang F Fujii H Fukunaga C Gabyshev N Garmash A Gershon T Guo R Haba J Handa F Hara T Harada Y Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hinz L Hojo T Hoshi Y 《Physical review letters》2003,90(2):021801
We report the first measurement of the branching fraction for the inclusive decay B-->X(s)l(+)l(-), where l is either an electron or a muon, and X(s) is a hadronic recoil system that contains an s quark. We analyzed a data sample of 65.4 x 10(6) B meson pairs collected with the Belle detector at the KEKB e(+)e(-) asymmetric-energy collider. We find B(B-->X(s)l(+)l(-))=[6.1 +/-1.4(stat) +1.4-1.1(syst)] x 10(-6) for dilepton masses greater than 0.2 GeV/c(2). 相似文献
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Aubert B Barate R Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Palano A Pappagallo M Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE 《Physical review letters》2005,95(22):221801
We present evidence for the b --> d penguin-dominated decays B+ --> K0K+ and B0 --> K0K0 in 227 x 10(6) Y(4S) --> BB decays collected with the BABAR detector. We measure the branching fractions B(B+ --> K0K+) = (1.5 +/- 0.5 +/- 0.1) x 10(-6)(< 2.4 x 10(-6)) and B(B0 --> K0K0) = [formula: see text], where the uncertainties are statistical and systematic, respectively. We also present improved measurements of the charge-averaged branching fraction B(B+ --> K0pi+) = (26.0 +/- 1.3 +/- 1.0) x 10(-6) and CP-violating charge asymmetry A(CP) (K0pi+) = -0.09 +/- 0.05 +/- 0.01), where the uncertainties are statistical and systematic, respectively. 相似文献