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Measurement of the ratio of b quark production cross sections in pp collisions at √s=630 GeV and √s=1800 GeV

Physical Review D Particles Fields Gravitation and Cosmology 66:3 (2002)

Authors:

D Acosta, T Affolder, H Akimoto, MG Albrow, D Ambrose, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, A Artikov, T Asakawa, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, S Bailey, P De Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Belforte, WH Bell, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S Van Den Brink, C Bromberg, M Brozovic, E Brubaker, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, S Cabrera, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, W Caskey, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, JY Chung, YS Chung, CI Ciobanu, AG Clark, AP Colijn, A Connolly, M Convery, J Conway, M Cordelli, J Cranshaw, R Culbertson, D Dagenhart

Abstract:

We report a measurement of the ratio of the bottom quark production cross section in antiproton-proton collisions at (Formula Presented)=630 GeV to 1800 GeV using bottom quarks with transverse momenta greater than 10.75 GeV identified through their semileptonic decays and long lifetimes. The measured ratio σ(630)/ σ(1800) 50.171±.024±.012 is in good agreement with next-to-leading order quantum chromodynamics.
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Properties of hadronic final states in diffractive deep inelastic ep scattering at DESY HERA

Physical Review D 65:5 (2002)

Authors:

S Chekanov, M Derrick, D Krakauer, S Magill, B Musgrave, A Pellegrino, J Repond, R Yoshida, MCK Mattingly, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, GC Romeo, L Cifarelli, F Cindolo, A Contin, M Corradi, S De Pasquale, P Giusti, G Iacobucci, G Levi, A Margotti, T Massam, R Nania, F Palmonari, A Pesci, G Sartorelli, A Zichichi, G Aghuzumtsyan, I Brock, S Goers, H Hartmann, E Hilger, P Irrgang, HP Jakob, A Kappes, UF Katz, R Kerger, O Kind, E Paul, J Rautenberg, H Schnurbusch, A Stifutkin, J Tandler, KC Voss, A Weber, H Wieber, DS Bailey, NH Brook, JE Cole, B Foster, GP Heath, HF Heath, S Robins, E Rodrigues, J Scott, RJ Tapper, M Wing, M Capua, A Mastroberardino, M Schioppa, G Susinno, HY Jeoung, JY Kim, JH Lee, IT Lim, KJ Ma, MY Pac, A Caldwell, M Helbich, W Liu, X Liu, B Mellado, S Paganis, S Sampson, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, K Klimek, K Olkiewicz, MB Przybycień, P Stopa, L Zawiejski, B Bednarek, I Grabowska-Bold, K Jeleń, D Kisielewska, AM Kowal, M Kowal, T Kowalski, B Mindur, M Przybycień, E Rulikowska-Zarȩbska

Abstract:

Characteristics of the hadronic final state of diffractive deep inelastic scattering events ep→eXp were studied in the kinematic range 4
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Search for radiative b-hadron decays in pp̅ collisions at √s=1.8 TeV

Physical Review D Particles Fields Gravitation and Cosmology 66:11 (2002)

Authors:

D Acosta, T Affolder, H Akimoto, MG Albrow, D Ambrose, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, A Artikov, T Asakawa, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, S Bailey, P De Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Behari, S Belforte, WH Bell, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, J Berryhill, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, C Bromberg, M Brozovic, E Brubaker, N Bruner, J Budagov, HS Budd, K Burkett, G Busetto, KL Byrum, S Cabrera, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, W Caskey, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, JY Chung, WH Chung, YS Chung, CI Ciobanu, AG Clark, M Coca, AP Colijn, A Connolly, M Convery, J Conway, M Cordelli, J Cranshaw, R Culbertson, D Dagenhart, S D’Auria

Abstract:

We have performed a search for radiative 6-hadron decays using events produced in pp̅ collisions at √s=1.8TeV and collected by the Collider Detector at Fermilab. The decays we considered were B0̅d→K*0(→K-π+γ, B0̅s→φ(→K+K-)γ,0b→γ(→p03C0-)γ), and their charge conjugates. Two independent methods to identify photons from such decays were employed. In the first method, the photon was detected in the electromagnetic calorimeter. In the second method, the photon was identified by an electron-positron pair produced through the external photon conversion before the tracking detector volume. By combining the two methods we obtain upper limits on the branching fractions for the B0̅d, B0̅s and γ,0b radiative decays which, at the 95% confidence level, are found to be B(B0̅d→K*0γ<1.4×-4,B(B0̅d→φγ)<1.6×-4,and (γ,0b→γγ)<1.9×-3.
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Study of CP-violating asymmetries in B0→ π+π-K+π- decays

Physical Review D 65:5 (2002)

Authors:

B Aubert, D Boutigny, JM Gaillard, A Hicheur, Y Karyotakis, JP Lees, P Robbe, V Tisserand, A Palano, A Pompili, GP Chen, JC Chen, ND Qi, G Kong, P Wang, YS Zhu, G Eigen, B Stugu, GS Abrams, AW Borgland, AB Breon, DN Brown, J Button-Shafer, RN Cahn, AR Clark, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, JF Kral, C LeClerc, ME Levi, G Lynch, PJ Oddone, A Perazzo, M Pripstein, NA Roe, A Romosan, MT Ronan, VG Shelkov, AV Telnov, WA Wenzel, PG Bright-Thomas, TJ Harrison, CM Hawkes, DJ Knowles, SW O'Neale, RC Penny, AT Watson, NK Watson, T Deppermann, K Goetzen, H Koch, M Kunze, B Lewandowski, K Peters, H Schmuecker, M Steinke, JC Andress, NR Barlow, W Bhimji, N Chevalier, PJ Clark, WN Cottingham, N Dyce, B Foster, C Mackay, FF Wilson, K Abe, C Hearty, TS Mattison, JA McKenna, D Thiessen, S Jolly, AK McKemey, VE Blinov, AD Bukin, DA Bukin, AR Buzykaev, VB Golubev, VN Ivanchenko, AA Korol, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, VI Telnov, AN Yushkov, D Best, M Chao, D Kirkby, AJ Lankford, M Mandelkern, S McMahon, DP Stoker

Abstract:

We present a measurement of the time-dependent CP-violating asymmetries in neutral B decays to the eigenstate, and an updated measurement of the charge asymmetry in B0→K+π-~ decays. In a sample of 33 million Y(4S)→BB̄ decays collected with the BABAR detector at the SLAC PEP-II asymmetric B factory, we find 65-11 +12 and 217±18 K+π- candidates and measure the asymmetry parameters Sππ=0.03-0.56 +0.53±0.111, Cππ=-0.25-0.17 +0.45±0.14, and AKπ = -0.07±0. 08±0.02, where the first error is statistical and the second is systematic. © 2002 The American Physical Society.
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Study of time-dependent CP-violating asymmetries and flavor oscillations in neutral B decays at the γ (4S)

Physical Review D 66:3 (2002)

Authors:

B Aubert, D Boutigny, JM Gaillard, A Hicheur, Y Karyotakis, JP Lees, P Robbe, V Tisserand, A Palano, A Pompili, GP Chen, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, B Stugu, GS Abrams, AW Borgland, AB Breon, DN Brown, J Button-Shafer, RN Cahn, AR Clark, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, JF Kral, C Leclerc, ME Levi, G Lynch, PJ Oddone, M Pripstein, NA Roe, A Romosan, MT Ronan, VG Shelkov, AV Telnov, WA Wenzel, TJ Harrison, CM Hawkes, DJ Knowles, SW O’neale, RC Penny, AT Watson, NK Watson, T Deppermann, K Goetzen, H Koch, M Kunze, B Lewandowski, K Peters, H Schmuecker, M Steinke, NR Barlow, W Bhimji, N Chevalier, PJ Clark, WN Cottingham, B Foster, C Mackay, FF Wilson, K Abe, C Hearty, TS Mattison, JA McKenna, D Thiessen, S Jolly, AK McKemey, VE Blinov, AD Bukin, DA Bukin, AR Buzykaev, VB Golubev, VN Ivanchenko, AA Korol, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, VI Telnov, AN Yushkov, D Best, M Chao, D Kirkby, AJ Lankford, M Mandelkern, S McMahon, DP Stoker, K Arisaka, C Buchanan, S Chun, DB Macfarlane, S Prell

Abstract:

We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb-1 recorded at the γ(4S) resonance and 3.9 fb-1 off resonance. One of the neutral B mesons, which are produced in pairs at the γ(4S), is fully reconstructed in the CP decay modes J/ ψKS 0, ψ(2S)KS 0, χc1KS 0, J/ψK*0 (K*0→KS 0π0) and J/ψKL 0, or in flavor-eigenstate modes involving D(*)π/p/a1 and J/ψK*0 (K*0→K+π -). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. A neural netsvork tagging algorithm is used to recover events without a clear lepton or kaon tag. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities, the time-difference resolution function, and the B0-B̄0 oscillation frequency Δmd are measured with a sample of about 6350 fully-reconstructed B0 decays in hadronic flavor-eigenstate modes. A maximum-likelihood fit to this flavor eigenstate sample finds Δmd=0.516±0.016(stat)±0.010(syst) ps -1. The value of the asymmetry amplitude sin 2β is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B0 decays in the CP-eigenstate modes. We find sin 2β=0.59 ±0.14(stat)±0. 05(syst), demonstrating that CP violation exists in the neutral B meson system. We also determine the value of the CP violation parameter |λ|=0. 93±0.09(stat)±0.03(syst), which is consistent with the expectation of |λ|=1 for no direct CP violation. © 2002 The American Physical Society.
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