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Measurement of open beauty production in photoproduction at HERA

European Physical Journal C 18:4 (2001) 625-637

Authors:

J Breitweg, S Chekanov, M Derrick, D Krakauer, S Magill, B Musgrave, A Pellegrino, J Repond, R Stanek, R Yoshida, MCK Mattingly, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, G Cara 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, C Amelung, I Brock, K Coböken, S Goers, H Hartmann, K Heinloth, 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, O Barret, NH Brook, JE Cole, B Foster, GP Heath, HF Heath, S Robins, E Rodrigues, J Scott, RJ Tapper, M Capua, A Mastroberardino, M Schioppa, G Susinno, HY Jeoung, JY Kim, JH Lee, IT Lim, KJ Ma, MY Pac, A Caldwell, W Liu, X Liu, B Mellado, S Paganis, S Sampson, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, K Klimek, K Olkiewicz, K Piotrzkowski, MB Przybycień, P Stopa, L Zawiejski, B Bednarek, K Jeleń, D Kisielewska, AM Kowal, T Kowalski, E Rulikowska-Zarebska

Abstract:

The production and semi-leptonic decay of heavy quarks have been studied in the photoproduction process e+p → e+ + dijet + e- + X with the ZEUS detector at HERA using an integrated luminosity of 38.5 pb-1. Events with photon-proton centre-of-mass energies, Wγ, between 134 and 269 GeV and a photon virtuality, Q2, less than 1 GeV2 were selected requiring at least two jets of transverse energy Ejet1(2) T > 7(6) GeV and an electron in the final state. The electrons were identified by employing the ionisation energy loss measurement. The contribution of beauty quarks was determined using the transverse momentum of the electron relative to the axis of the closest jet, prel T. The data, after background subtraction, were fit with a Monte Carlo simulation including beauty and charm decays. The measured beauty cross section was extrapolated to the parton level with the b quark restricted to the region of transverse momentum pb T > = 5 GeV and pseudorapidity |ηb| < 2. The extrapolated cross section is 1.6 ± 0.4 (stat.)+0.3 -0.5(syst.)+0.2 -0.4(ext.) nb. The result is compared to a perturbative QCD calculation performed to next-to-leading order.

Measurement of the W boson mass with the Collider Detector at Fermilab

Physical Review D Particles Fields Gravitation and Cosmology 64:5 (2001)

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, F Bedeschi, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, B Bevensee, A Bhatti, M Binkley, D Bisello, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, M Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, YS Chung, CI Ciobanu, AG Clark, A Connolly, J Conway, J Cooper, M Cordelli, J Cranshaw, D Cronin-Hennessy, R Cropp, R Culbertson, D Dagenhart, F DeJongh, S Dell’Agnello, M Dell’Orso

Abstract:

We present a measurement of the W boson mass using data collected with the CDF detector during the 1994–1995 collider run at the Fermilab Tevatron. A fit to the transverse mass spectrum of a sample of 30115 [Formula Presented] events recorded in an integrated luminosity of 84 [Formula Presented] gives a mass [Formula Presented] A fit to the transverse mass spectrum of a sample of 14740 [Formula Presented] events from 80 [Formula Presented] gives a mass [Formula Presented] The dominant contributions to the sys- tematic uncertainties are the uncertainties in the electron energy scale and the muon momentum scale, [Formula Presented] and [Formula Presented] respectively. The combined value for the electron and muon channel is [Formula Presented] When combined with previously published CDF measurements, we obtain [Formula Presented] © 2001 The American Physical Society.

Measurement of the inclusive jet cross section in pp collisions at \/s = 1.8 TeV

Physical Review D 64:3 (2001)

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, 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, B Bevensee, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, W Caskey, J Cassada, 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, YS Chung, CI Ciobanu, AG Clark, A Connolly, J Conway, M Cordelli, J Cranshaw, D Cronin-Hennessy, R Cropp, R Culbertson, D Dagenhart, S D’Auria

Abstract:

We present results from the measurement of the inclusive jet cross section for jet transverse energies from 40 to 465 GeV in the pseudorapidity range 0.1< | ?7|< 0.7. The results are based on 87 pb~' of data collected by the CDF Collaboration at the Fermilab Tevatron collider. The data are consistent with previously published results. The data are also consistent with QCD predictions given the flexibility allowed from current knowledge of the proton parton distributions. We develop a new procedure for ranking the agreement of the parton distributions with data and find that the data are best described by QCD predictions using the parton distribution functions which have a large gluon contribution at high ET (CTEQ4HJ).

Observation of orbitally excited B mesons in pp̄ collisions at √s=1.8 TeV

Physical Review D 64:7 (2001)

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P De Barbara, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, F Bedeschi, S Belferte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, S Bertolucci, B Bevensee, A Bhatti, C Bigongiari, M Binkley, D Bisello, RE Blair, C Blocker, K Bloom, B Blumenfeld, BS Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandi, S Van Den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, M Campbell, A Caner, W Carithers, J Carlson, D Carlsmith, J Cassada, 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, S Cihangir, CI Ciobanu, AG Clark, M Cobal, E Cocca, A Connolly, J Conway, J Cooper, M Cordelli, D Costanzo, J Cranshaw, D Cronin-Hennessy

Abstract:

We measure the relative rate of production of orbitally excited (L=1) states of B mesons (B**) by observing their decays into Bπ±. We reconstruct B mesons through semileptonic decay channels using data collected pp̄ collisions at √s= 1.8 TeV. The fraction of light B mesons that are produced as L= 1B** states is measured to be 0.28±0.06(stat)±0.03(syst). We also measure the collective mass of the B** states, and quantify the result by quoting the (model-dependent) mass of the lowest B** state to be m(B1) = 5.71 ±0.02GeV/c2. ©2001 The American Physical Society.

Quasi-model-independent search for new physics at large transverse momentum

Physical Review D Particles Fields Gravitation and Cosmology 64:1 (2001)

Authors:

VM Abazov, B Abbott, A Abdesselam, M Abolins, V Abramov, BS Acharya, DL Adams, M Adams, SN Ahmed, GD Alexeev, GA Alves, N Amos, EW Anderson, MM Baarmand, VV Babintsev, L Babukhadia, TC Bacon, A Baden, B Baldin, PW Balm, S Banerjee, E Barberis, P Baringer, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, M Begel, A Belyaev, SB Beri, G Bernardi, I Bertram, A Besson, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Bhattacharjee, G Blazey, S Blessing, A Boehnlein, NI Bojko, F Borcherding, K Bos, A Brandt, R Breedon, G Briskin, R Brock, G Brooijmans, A Bross, D Buchholz, M Buehler, V Buescher, VS Burtovoi, JM Butler, F Canelli, W Carvalho, D Casey, Z Casilum, H Castilla-Valdez, D Chakraborty, KM Chan, SV Chekulaev, DK Cho, S Choi, S Chopra, JH Christenson, M Chung, D Claes, AR Clark, J Cochran, L Coney, B Connolly, WE Cooper, D Coppage, MAC Cummings, D Cutts, GA Davis, K Davis, K De, SJ Jong, K Del Signore, M Demarteau, R Demina, P Demine, D Denisov, SP Denisov, S Desai, HT Diehl, M Diesburg, G Loreto, S Doulas, P Draper, Y Ducros, LV Dudko, S Duensing, L Duflot, SR Dugad, A Dyshkant

Abstract:

We apply a quasi-model-independent strategy (“SLEUTH”) to search for new high [Formula Presented] physics in ≈100 [Formula Presented] of [Formula Presented] collisions at [Formula Presented] collected by the DØ experiment during 1992–1996 at the Fermilab Tevatron. Over 32 [Formula Presented] [Formula Presented] [Formula Presented] and [Formula Presented] exclusive final states are systematically analyzed for hints of physics beyond the standard model. Simultaneous sensitivity to a variety of models predicting new phenomena at the electroweak scale is demonstrated by testing the method on a particular signature in each set of final states. No evidence of new high [Formula Presented] physics is observed in the course of this search, and we find that 89% of an ensemble of hypothetical similar experimental runs would have produced a final state with a candidate signal more interesting than the most interesting observed in these data. © 2001 The American Physical Society.