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Measurements of the B→Xsγ branching fraction and photon spectrum from a sum of exclusive final states

Physical Review D Particles Fields Gravitation and Cosmology 72:5 (2005)

Authors:

B Aubert, R Barate, D Boutigny, F Couderc, Y Karyotakis, JP Lees, V Poireau, V Tisserand, A Zghiche, E Grauges, A Palano, M Pappagallo, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu, GS Abrams, M Battaglia, AB Breon, DN Brown, J Button-Shafer, RN Cahn, E Charles, CT Day, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, G Kukartsev, G Lynch, LM Mir, PJ Oddone, TJ Orimoto, M Pripstein, NA Roe, MT Ronan, WA Wenzel, M Barrett, KE Ford, TJ Harrison, AJ Hart, CM Hawkes, SE Morgan, AT Watson, M Fritsch, K Goetzen, T Held, H Koch, B Lewandowski, M Pelizaeus, K Peters, T Schroeder, M Steinke, JT Boyd, JP Burke, N Chevalier, WN Cottingham, T Cuhadar-Donszelmann, BG Fulsom, C Hearty, NS Knecht, TS Mattison, JA McKenna, A Khan, P Kyberd, M Saleem, L Teodorescu, AE Blinov, VE Blinov, AD Bukin, VP Druzhinin, VB Golubev, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, EP Solodov, AN Yushkov, D Best, M Bondioli, M Bruinsma, M Chao, S Curry, I Eschrich, D Kirkby, AJ Lankford, P Lund, M Mandelkern, RK Mommsen, W Roethel, DP Stoker

Abstract:

Using 88.9 million BB̄ events collected by the BABAR detector at the Υ(4S), we measure the branching fraction for the radiative penguin process B→Xsγ from the sum of 38 exclusive final states. The inclusive branching fraction above a minimum photon energy Eγ>1.9GeV is B(b→sγ)=(3.27±0.18(stat)-0.40+0.55(syst)-0.09+0.04(theory)) ×10-4. We also measure the isospin asymmetry between B- →Xsūγ and B̄0→Xsd̄γ to be Δ0-=-0.006±0.058(stat)±0.009(syst)±0.024(B̄0/B-) . The photon energy spectrum is measured in the B rest frame, from which moments are derived for different values of the minimum photon energy. We present fits to the photon spectrum and moments which give the heavy-quark parameters mb and μπ2. The fitted parameters are consistent with those obtained from semileptonic B→Xc ν decays, and are useful inputs for the extraction of |Vub| from measurements of semileptonic B→Xu ν decays. © 2005 The American Physical Society.
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Precision measurement of the Λc+ baryon mass

Physical Review D - Particles, Fields, Gravitation and Cosmology 72:5 (2005)

Authors:

B Aubert, R Barate, D Boutigny, F Couderc, Y Karyotakis, JP Lees, V Poireau, V Tisserand, A Zghiche, E Grauges, A Palano, M Pappagallo, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu, GS Abrams, M Battaglia, AB Breon, DN Brown, J Button-Shafer, RN Cahn, E Charles, CT Day, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, G Kukartsev, G Lynch, LM Mir, PJ Oddone, TJ Orimoto, M Pripstein, NA Roe, MT Ronan, WA Wenzel, M Barrett, KE Ford, TJ Harrison, AJ Hart, CM Hawkes, SE Morgan, AT Watson, M Fritsch, K Goetzen, T Held, B Lewandowski, M Pelizaeus, K Peters, T Schroeder, M Steinke, JT Boyd, JP Burke, N Chevalier, WN Cottingham, T Cuhadar-Donszelmann, BG Fulsom, C Hearty, NS Knecht, TS Mattison, JA McKenna, A Khan, P Kyberd, M Saleem, L Teodorescu, AE Blinov, VE Blinov, AD Bukin, VP Druzhinin, VB Golubev, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, EP Solodov, AN Yushkov, D Best, M Bondioli, M Bruinsma, M Chao, S Curry, I Eschrich, D Kirkby, AJ Lankford, P Lund, M Mandelkern, RK Mommsen, W Roethel, DP Stoker, C Buchanan

Abstract:

The Λc+ baryon mass is measured using Λc+→ΛKS0K+ and Λc+→Σ0KS0K+ decays reconstructed in 232fb-1 of data collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring. The Λc+ mass is measured to be 2286.46±0.14MeV/c2. The dominant systematic uncertainties arise from the amount of material in the tracking volume and from the magnetic field strength. © 2005 The American Physical Society.
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Search for the rare decay B̄0→D*0γ

Physical Review D - Particles, Fields, Gravitation and Cosmology 72:5 (2005)

Authors:

B Aubert, R Barate, D Boutigny, F Couderc, Y Karyotakis, JP Lees, V Poireau, V Tisserand, A Zghiche, E Grauges, A Palano, M Pappagallo, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu, GS Abrams, AW Borgland, AB Breon, DN Brown, J Button-Shafer, RN Cahn, E Charles, CT Day, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, G Kukartsev, G Lynch, LM Mir, PJ Oddone, TJ Orimoto, M Pripstein, NA Roe, MT Ronan, WA Wenzel, M Barrett, KE Ford, TJ Harrison, AJ Hart, CM Hawkes, SE Morgan, AT Watson, M Fritsch, K Goetzen, T Held, H Koch, B Lewandowski, M Pelizaeus, K Peters, T Schroeder, M Steinke, JT Boyd, JP Burke, N Chevalier, WN Cottingham, MP Kelly, T Cuhadar-Donszelmann, C Hearty, NS Knecht, TS Mattison, JA McKenna, D Thiessen, A Khan, P Kyberd, L Teodorescu, AE Blinov, VE Blinov, AD Bukin, VP Druzhinin, VB Golubev, VN Ivanchenko, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, EP Solodov, AN Yushkov, D Best, M Bondioli, M Bruinsma, M Chao, I Eschrich, D Kirkby, AJ Lankford, M Mandelkern, RK Mommsen, W Roethel, DP Stoker, C Buchanan

Abstract:

We report on a search for the rare decay B̄0→D*0γ, which in the standard model is dominated by W-exchange. The analysis is based on a data sample comprising 87.8×106 BB̄ pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. No significant signal is observed, and an upper limit on the branching fraction of 2.5×10-5 at the 90% confidence level is obtained. © 2005 The American Physical Society.
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Study of B→π ν and B→ρ ν decays and determination of

Physical Review D - Particles, Fields, Gravitation and Cosmology 72:5 (2005)

Authors:

B Aubert, R Barate, D Boutigny, F Couderc, Y Karyotakis, JP Lees, V Poireau, V Tisserand, A Zghiche, E Grauges, A Palano, M Pappagallo, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu, GS Abrams, M Battaglia, AB Breon, DN Brown, J Button-Shafer, RN Cahn, E Charles, CT Day, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, G Kukartsev, G Lynch, LM Mir, PJ Oddone, TJ Orimoto, M Pripstein, NA Roe, MT Ronan, WA Wenzel, M Barrett, KE Ford, TJ Harrison, AJ Hart, CM Hawkes, SE Morgan, AT Watson, M Fritsch, K Goetzen, T Held, H Koch, B Lewandowski, M Pelizaeus, K Peters, T Schroeder, M Steinke, JT Boyd, JP Burke, N Chevalier, WN Cottingham, MP Kelly, T Cuhadar-Donszelmann, BG Fulsom, C Hearty, NS Knecht, TS Mattison, JA McKenna, A Khan, P Kyberd, M Saleem, L Teodorescu, AE Blinov, VE Blinov, AD Bukin, VP Druzhinin, VB Golubev, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, EP Solodov, AN Yushkov, D Best, M Bondioli, M Bruinsma, M Chao, I Eschrich, D Kirkby, AJ Lankford, M Mandelkern, RK Mommsen, W Roethel, DP Stoker, C Buchanan

Abstract:

We present an analysis of exclusive charmless semileptonic B-meson decays based on 83×106 BB̄ pairs recorded with the BABAR detector at the Υ(4S) resonance. Using isospin symmetry, we measure branching fractions B(B0→π- +ν)=(1.38±0.10±0.16±0.08)×10-4 and B(B0→ρ- +ν)=(2.14±0.21±0.48±0.28)×10-4, where the errors are statistical, experimental systematic, and due to form-factor shape uncertainties. We compare the measured distribution in q2, the momentum-transfer squared, with theoretical predictions for the form factors from lattice QCD and light-cone sum rules, and extract the Cabibbo-Kobayashi- Maskawa (CKM) matrix element |Vub|=(3.82±0.14±0.22±0.11-0. 52+0.88)×10-3 from B→π ν, where the fourth error reflects the uncertainty of the form-factor normalization. © 2005 The American Physical Society.
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Measurement of double charmonium production in e+e- annihilations at s=10.6GeV

Physical Review D Particles Fields Gravitation and Cosmology 72:3 (2005) 1-7

Authors:

B Aubert, R Barate, D Boutigny, F Couderc, Y Karyotakis, JP Lees, V Poireau, V Tisserand, A Zghiche, E Grauges, A Palano, M Pappagallo, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu, GS Abrams, M Battaglia, AB Breon, DN Brown, J Button-Shafer, RN Cahn, E Charles, CT Day, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, G Kukartsev, G Lynch, LM Mir, PJ Oddone, TJ Orimoto, M Pripstein, NA Roe, MT Ronan, WA Wenzel, M Barrett, KE Ford, TJ Harrison, AJ Hart, CM Hawkes, SE Morgan, AT Watson, M Fritsch, K Goetzen, T Held, H Koch, B Lewandowski, M Pelizaeus, K Peters, T Schroeder, M Steinke, JT Boyd, JP Burke, N Chevalier, WN Cottingham, MP Kelly, T Cuhadar-Donszelmann, BG Fulsom, C Hearty, NS Knecht, TS Mattison, JA McKenna, A Khan, P Kyberd, M Saleem, L Teodorescu, AE Blinov, VE Blinov, AD Bukin, VP Druzhinin, VB Golubev, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, EP Solodov, AN Yushkov, D Best, M Bondioli, M Bruinsma, M Chao, I Eschrich, D Kirkby, AJ Lankford, M Mandelkern, RK Mommsen, W Roethel, DP Stoker, C Buchanan

Abstract:

We study e+e-→J/ψcc̄ by measuring the invariant mass distribution recoiling against fully reconstructed J/ψ decays, using 124fb-1 of data collected at a center-of-mass energy of 10.6 GeV with the BABAR detector. We observe signals for ηc(1S), χc0, and ηc(2S) in the recoil mass distribution, thus confirming previous measurements. We measure σ(e+e-→J/ψ+cc̄)B(cc̄→>2charged) to be 17.6±2.8(stat)-2.1+1.5(syst)fb, 10.3±2.5(stat)-1.8+1.4(syst)fb, and 16.4±3.7(stat)-3.0+2.4(syst)fb with cc̄=ηc(1S), χc0, and ηc(2S), respectively. © 2005 The American Physical Society.
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