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Dielectron Widths of the Υ(1S,2S,3S) Resonances

Physical Review Letters American Physical Society (APS) 96:9 (2006) 092003

Authors:

JL Rosner, NE Adam, JP Alexander, K Berkelman, DG Cassel, JE Duboscq, KM Ecklund, R Ehrlich, L Fields, RS Galik, L Gibbons, R Gray, SW Gray, DL Hartill, BK Heltsley, D Hertz, CD Jones, J Kandaswamy, DL Kreinick, VE Kuznetsov, H Mahlke-Krüger, TO Meyer, PUE Onyisi, JR Patterson, D Peterson, EA Phillips, J Pivarski, D Riley, A Ryd, AJ Sadoff, H Schwarthoff, X Shi, S Stroiney, WM Sun, T Wilksen, M Weinberger, SB Athar, P Avery, L Breva-Newell, R Patel, V Potlia, H Stoeck, J Yelton, P Rubin, C Cawlfield, BI Eisenstein, I Karliner, D Kim, N Lowrey, P Naik, C Sedlack, M Selen, EJ White, J Wiss, MR Shepherd, D Besson, TK Pedlar, D Cronin-Hennessy, KY Gao, DT Gong, J Hietala, Y Kubota, T Klein, BW Lang, R Poling, AW Scott, A Smith, S Dobbs, Z Metreveli, KK Seth, A Tomaradze, P Zweber, J Ernst, K Arms, H Severini, SA Dytman, W Love, S Mehrabyan, V Savinov, O Aquines, Z Li, A Lopez, H Mendez, J Ramirez, GS Huang, DH Miller, V Pavlunin, B Sanghi, IPJ Shipsey, B Xin, GS Adams, M Anderson, JP Cummings, I Danko, J Napolitano, Q He, J Insler, H Muramatsu, CS Park, EH Thorndike, TE Coan, YS Gao, F Liu, R Stroynowski, M Artuso, S Blusk, J Butt, J Li, N Menaa, R Mountain, S Nisar, K Randrianarivony, R Redjimi, R Sia, T Skwarnicki, S Stone, JC Wang, K Zhang, SE Csorna, G Bonvicini, D Cinabro, M Dubrovin, A Lincoln, DM Asner, KW Edwards, RA Briere, J Chen, T Ferguson, G Tatishvili, H Vogel, ME Watkins

Measurement of the azimuthal angle distribution of leptons from W boson decays as a function of the W transverse momentum in pp - collisions at s=1.8TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 73:5 (2006)

Authors:

D Acosta, T Affolder, MG Albrow, D Ambrose, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, A Artikov, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, 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, A Beretvas, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, A Bocci, A Bodek, G Bolla, A Bolshov, D Bortoletto, J Boudreau, C Bromberg, E Brubaker, J Budagov, HS Budd, K Burkett, G Busetto, KL Byrum, S Cabrera, M Campbell, W Carithers, D Carlsmith, A Castro, D Cauz, A Cerri, L Cerrito, J Chapman, C Chen, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, ML Chu, JY Chung, WH Chung, YS Chung, CI Ciobanu, AG Clark, M Coca, A Connolly, M Convery, J Conway, M Cordelli, J Cranshaw, R Culbertson, D Dagenhart, S D'Auria, P De Barbaro, S De Cecco, S Dell'Agnello, M Dell'Orso, S Demers, L Demortier, M Deninno, D De Pedis, PF Derwent, C Dionisi, JR Dittmann, A Dominguez, S Donati, M D'Onofrio, T Dorigo, N Eddy, R Erbacher, D Errede, S Errede

Abstract:

We present the first measurement of the A2 and A3 angular coefficients of the W boson produced in proton-antiproton collisions. We study W→eνe and W→μνμ candidate events produced in association with at least one jet at CDF, during Run Ia and Run Ib of the Tevatron at s=1.8TeV. The corresponding integrated luminosity was 110pb-1. The jet balances the transverse momentum of the W and introduces QCD effects in W boson production. The extraction of the angular coefficients is achieved through the direct measurement of the azimuthal angle of the charged lepton in the Collins-Soper rest-frame of the W boson. The angular coefficients are measured as a function of the transverse momentum of the W boson. The electron, muon, and combined results are in good agreement with the standard model prediction, up to order αs2 in QCD. © 2006 The American Physical Society.

Observation of ψ(3770)→ππJ/ψ and Measurement of Γee[ψ(2S)]

Physical Review Letters 96:8 (2006)

Authors:

NE Adam, JP Alexander, K Berkelman, DG Cassel, V Crede, JE Duboscq, KM Ecklund, R Ehrlich, L Fields, RS Galik, L Gibbons, B Gittelman, R Gray, SW Gray, DL Hartill, BK Heltsley, D Hertz, CD Jones, J Kandaswamy, DL Kreinick, VE Kuznetsov, H Mahlke-Krüger, TO Meyer, PUE Onyisi, JR Patterson, D Peterson, EA Phillips, J Pivarski, D Riley, A Ryd, AJ Sadoff, H Schwarthoff, X Shi, MR Shepherd, S Stroiney, WM Sun, D Urner, T Wilksen, KM Weaver, M Weinberger, SB Athar, P Avery, L Breva-Newell, R Patel, V Potlia, H Stoeck, J Yelton, P Rubin, C Cawlfield, BI Eisenstein, GD Gollin, I Karliner, D Kim, N Lowrey, P Naik, C Sedlack, M Selen, EJ White, J Williams, J Wiss, DM Asner, KW Edwards, D Besson, TK Pedlar, D Cronin-Hennessy, KY Gao, DT Gong, J Hietala, Y Kubota, T Klein, BW Lang, SZ Li, R Poling, AW Scott, A Smith, S Dobbs, Z Metreveli, KK Seth, A Tomaradze, P Zweber, J Ernst, H Severini, SA Dytman, W Love, S Mehrabyan, JA Mueller, V Savinov, Z Li, A Lopez, H Mendez, J Ramirez, GS Huang, DH Miller, V Pavlunin, B Sanghi, IPJ Shipsey, GS Adams, M Anderson, JP Cummings, I Danko

Abstract:

We observe signals for the decays ψ(3770)→XJ/ψ from data acquired with the CLEO detector operating at the CESR e+e- collider with s=3773MeV. We measure the following branching fractions B(ψ(3770)→XJ/ ψ) and significances: (189±20±20)×10-5 (11.6σ) for X=π+π-, (80±25±16)×10-5 (3.4σ) for X=π0π0, and (87±33±22)×10-5 (3.5σ) for X=η, where the errors are statistical and systematic, respectively. The radiative return process e+e-→γψ(2S) populates the same event sample and is used to measure Γee[ψ(2S)]=(2.54±0.03±0.11)keV. © 2006 The American Physical Society.

A photometric redshift of z = 6.39 ± 0.12 for GRB 050904

Nature 440:7081 (2006) 181-183

Authors:

JB Haislip, MC Nysewander, DE Reichart, A Levan, N Tanvir, SB Cenko, DB Fox, PA Price, AJ Castro-Tirado, J Gorosabel, CR Evans, E Figueredo, CL MacLeod, JR Kirschbrown, M Jelinek, S Guziy, A De Ugarte Postigo, ES Cypriano, A LaCluyze, J Graham, R Priddey, R Chapman, J Rhoads, AS Fruchter, DQ Lamb, C Kouveliotou, RAMJ Wijers, MB Bayliss, BP Schmidt, AM Soderberg, SR Kulkarni, FA Harrison, DS Moon, A Gal-Yam, MM Kasliwal, R Hudec, S Vitek, P Kubanek, JA Crain, AC Foster, JC Clemens, JW Bartelme, R Canterna, DH Hartmann, AA Henden, S Klose, HS Park, GG Williams, E Rol, P O'Brien, D Bersier, F Prada, S Pizarro, D Maturana, P Ugarte, A Alvarez, AJM Fernandez, MJ Jarvis, M Moles, E Alfaro, KM Ivarsen, ND Kumar, CE Mack, CM Zdarowicz, N Gehrels, S Barthelmy, DN Burrows

Abstract:

Gamma-ray bursts (GRBs) and their afterglows are the most brilliant transient events in the Universe. Both the bursts themselves and their afterglows have been predicted to be visible out to redshifts of z ≈ 20, and therefore to be powerful probes of the early Universe1,2. The burst GRB 000131, at z = 4.50, was hitherto the most distant such event identified3. Here we report the discovery of the bright near-infrared afterglow of GRB 050904 (ref. 4). From our measurements of the near-infrared afterglow, and our failure to detect the optical afterglow, we determine the photometric redshift of the burst to be z = 6.39-0.12+0.11 (refs 5-7). Subsequently, it was measured8 spectroscopically to be z = 6.29 ± 0.01, in agreement with our photometric estimate. These results demonstrate that GRBs can be used to trace the star formation, metallicity, and reionization histories of the early Universe. © 2006 Nature Publishing Group.

Search for anomalous semileptonic decay of heavy flavor hadrons produced in association with a W boson at CDF II

Physical Review D Particles Fields Gravitation and Cosmology 73:5 (2006)

Authors:

A Abulencia, D Acosta, J Adelman, T Affolder, T Akimoto, MG Albrow, D Ambrose, S Amerio, D Amidei, A Anastassov, K Anikeev, A Annovi, J Antos, M Aoki, G Apollinari, JF Arguin, T Arisawa, A Artikov, W Ashmanskas, A Attal, F Azfar, P Azzi-Bacchetta, P Azzurri, N Bacchetta, H Bachacou, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, V Bartsch, G Bauer, F Bedeschi, S Behari, S Belforte, G Bellettini, J Bellinger, A Belloni, EB Haim, D Benjamin, A Beretvas, J Beringer, T Berry, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, A Bolshov, D Bortoletto, J Boudreau, S Bourov, A Boveia, B Brau, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, M Campanelli, M Campbell, F Canelli, A Canepa, D Carlsmith, R Carosi, S Carron, M Casarsa, A Castro, P Catastini, D Cauz, M Cavalli-Sforza, A Cerri, L Cerrito, SH Chang, J Chapman, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, JP Chou, PH Chu, SH Chuang, K Chung, WH Chung

Abstract:

We present a search for anomalous semileptonic decays of heavy flavor hadrons produced in association with a W boson in proton-antiproton collisions at s=1.96TeV. We use 162pb-1 of data collected with the CDF II detector at the Fermilab Tevatron Collider. We select events with one W boson and at least one jet with an identified secondary vertex. In the jets with a secondary vertex we look for a semileptonic decay to a muon. We compare the number of jets with both a secondary vertex and a semileptonic decay and the kinematic properties of these jets, with the standard model expectation of W plus heavy flavor production and decay. No discrepancy is seen between the observation and the expectation, and we set limits on the production cross section of a B-like hadron with an anomalously high semileptonic branching ratio. © 2006 The American Physical Society.