Experimental discrimination between charge 2e/3 top quark and charge 4e/3 exotic quark production scenarios

Physical Review Letters 98:4 (2007)

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, T Andeen, S Anderson, B Andrieu, MS Anzelc, Y Arnoud, M Arov, A Askew, B Ãsman, ACS Assis Jesus, O Atramentov, C Autermann, C Avila, C Ay, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, P Banerjee, S Banerjee, E Barberis, P Bargassa, P Baringer, C Barnes, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, M Begalli, M Begel, C Belanger-Champagne, L Bellantoni, A Bellavance, JA Benitez, SB Beri, G Bernardi, R Bernhard, L Berntzon, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Binder, C Biscarat, KM Black, I Blackler, G Blazey, F Blekman, S Blessing, D Bloch, K Bloom, U Blumenschein, A Boehnlein, O Boeriu, TA Bolton, G Borissov, K Bos, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, D Brown, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Burdin, S Burke, TH Burnett, E Busato, CP Buszello, JM Butler, P Calfayan, S Calvet, J Cammin, S Caron, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, D Chakraborty

Abstract:

We present the first experimental discrimination between the 2e/3 and 4e/3 top quark electric charge scenarios, using top quark pairs (ttÌ„) produced in ppÌ„ collisions at s=1.96TeV by the Fermilab Tevatron Collider. We use 370pb-1 of data collected by the D0 experiment and select events with at least one high transverse momentum electron or muon, high transverse energy imbalance, and four or more jets. We discriminate between b- and bÌ„-quark jets by using the charge and momenta of tracks within the jet cones. The data are consistent with the expected electric charge, |q|=2e/3. We exclude, at the 92% C.L., that the sample is solely due to the production of exotic quark pairs QQÌ„ with |q|=4e/3. We place an upper limit on the fraction of QQÌ„ pairs Ï<0.80 at the 90% C.L. © 2007 The American Physical Society.

Measurement of the B+ production cross section in pp̄ collisions at s=1960GeV

Physical Review D Particles Fields Gravitation and Cosmology 75:1 (2007)

Authors:

A Abulencia, 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, 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, D Benjamin, A Beretvas, J Beringer, T Berry, A Bhatti, M Binkley, D Bisello, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, A Bolshov, D Bortoletto, J Boudreau, A Boveia, B Brau, L Brigliadori, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, S Budroni, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, M Campanelli, M Campbell, F Canelli, A Canepa, S Carillo, D Carlsmith, R Carosi, M Casarsa, A Castro, P Catastini, D Cauz, M Cavalli-Sforza, A Cerri, L Cerrito, SH Chang, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, JP Chou, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, M Ciljak, CI Ciobanu, MA Ciocci, A Clark

Abstract:

We present a new measurement of the B+ meson differential cross section dσ/dpT at s=1960GeV. The data correspond to an integrated luminosity of 739pb-1 collected with the upgraded CDF detector (CDF II) at the Fermilab Tevatron collider. B+ candidates are reconstructed through the decay B+→J/ψK+, with J/ψ→μ+μ-. The integrated cross section for producing B+ mesons with pT≥6GeV/c and |y|≤1 is measured to be 2.78±0.24μb. © 2007 The American Physical Society.

Experimental discrimination between charge 2e/3 top quark and charge 4e/3 exotic quark production scenarios.

Phys Rev Lett 98:4 (2007) 041801

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, T Andeen, S Anderson, B Andrieu, MS Anzelc, Y Arnoud, M Arov, A Askew, B Asman, ACS Assis Jesus, O Atramentov, C Autermann, C Avila, C Ay, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, P Banerjee, S Banerjee, E Barberis, P Bargassa, P Baringer, C Barnes, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, M Begalli, M Begel, C Belanger-Champagne, L Bellantoni, A Bellavance, JA Benitez, SB Beri, G Bernardi, R Bernhard, L Berntzon, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Binder, C Biscarat, KM Black, I Blackler, G Blazey, F Blekman, S Blessing, D Bloch, K Bloom, U Blumenschein, A Boehnlein, O Boeriu, TA Bolton, G Borissov, K Bos, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, D Brown, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Burdin, S Burke, TH Burnett, E Busato, CP Buszello, JM Butler, P Calfayan, S Calvet, J Cammin, S Caron, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, D Chakraborty, KM Chan, A Chandra, F Charles, E Cheu, F Chevallier, DK Cho, S Choi, B Choudhary, L Christofek, D Claes, B Clément, C Clément, Y Coadou, M Cooke, WE Cooper, D Coppage, M Corcoran, M-C Cousinou, B Cox, S Crépé-Renaudin, D Cutts, M Cwiok, H da Motta, A Das, M Das, B Davies, G Davies, GA Davis, K De, P de Jong, SJ de Jong, E De La Cruz-Burelo, C De Oliveira Martins, JD Degenhardt, F Déliot, M Demarteau, R Demina, P Demine, D Denisov, SP Denisov, S Desai, HT Diehl, M Diesburg, M Doidge, A Dominguez, H Dong, LV Dudko, L Duflot, SR Dugad, D Duggan, A Duperrin, J Dyer, A Dyshkant, M Eads, D Edmunds, T Edwards, J Ellison, J Elmsheuser, VD Elvira, S Eno, P Ermolov, H Evans, A Evdokimov, VN Evdokimov, SN Fatakia, L Feligioni, AV Ferapontov, T Ferbel, F Fiedler, F Filthaut, W Fisher, HE Fisk, I Fleck, M Ford, M Fortner, H Fox, S Fu, S Fuess, T Gadfort, CF Galea, E Gallas, E Galyaev, C Garcia, A Garcia-Bellido, J Gardner, V Gavrilov, A Gay, P Gay, D Gelé, R Gelhaus, CE Gerber, Y Gershtein, D Gillberg, G Ginther, N Gollub, B Gómez, A Goussiou, PD Grannis, H Greenlee, ZD Greenwood, EM Gregores, G Grenier, Ph Gris, J-F Grivaz, S Grünendahl, MW Grünewald, F Guo, J Guo, G Gutierrez, P Gutierrez, A Haas, NJ Hadley, P Haefner, S Hagopian, J Haley, I Hall, RE Hall, L Han, K Hanagaki, P Hansson, K Harder, A Harel, R Harrington, JM Hauptman, R Hauser, J Hays, T Hebbeker, D Hedin, JG Hegeman, JM Heinmiller, AP Heinson, U Heintz, C Hensel, K Herner, G Hesketh, MD Hildreth, R Hirosky, JD Hobbs, B Hoeneisen, H Hoeth, M Hohlfeld, SJ Hong, R Hooper, P Houben, Y Hu, Z Hubacek, V Hynek, I Iashvili, R Illingworth, AS Ito, S Jabeen, M Jaffré, S Jain, K Jakobs, C Jarvis, A Jenkins, R Jesik, K Johns, C Johnson, M Johnson, A Jonckheere, P Jonsson, A Juste, D Käfer, S Kahn, E Kajfasz, AM Kalinin, JM Kalk, JR Kalk, S Kappler, D Karmanov, J Kasper, P Kasper, I Katsanos, D Kau, R Kaur, R Kehoe, S Kermiche, N Khalatyan, A Khanov, A Kharchilava, YM Kharzheev, D Khatidze, H Kim, TJ Kim, MH Kirby, B Klima, JM Kohli, J-P Konrath, M Kopal, VM Korablev, J Kotcher, B Kothari, A Koubarovsky, AV Kozelov, J Kozminski, D Krop, A Kryemadhi, T Kuhl, A Kumar, S Kunori, A Kupco, T Kurca, J Kvita, S Lammers, G Landsberg, J Lazoflores, A-C Le Bihan, P Lebrun, WM Lee, A Leflat, F Lehner, V Lesne, J Leveque, P Lewis, J Li, QZ Li, JGR Lima, D Lincoln, J Linnemann, VV Lipaev, R Lipton, Z Liu, L Lobo, A Lobodenko, M Lokajicek, A Lounis, P Love, HJ Lubatti, M Lynker, AL Lyon, AKA Maciel, RJ Madaras, P Mättig, C Magass, A Magerkurth, A-M Magnan, N Makovec, PK Mal, HB Malbouisson, S Malik, VL Malyshev, HS Mao, Y Maravin, M Martens, R McCarthy, D Meder, A Melnitchouk, A Mendes, L Mendoza, M Merkin, KW Merritt, A Meyer, J Meyer, M Michaut, H Miettinen, T Millet, J Mitrevski, J Molina, NK Mondal, J Monk, RW Moore, T Moulik, GS Muanza, M Mulders, M Mulhearn, L Mundim, YD Mutaf, E Nagy, M Naimuddin, M Narain, NA Naumann, HA Neal, JP Negret, P Neustroev, C Noeding, A Nomerotski, SF Novaes, T Nunnemann, V O'dell, DC O'neil, G Obrant, V Oguri, N Oliveira, N Oshima, R Otec, GJ Otero Y Garzón, M Owen, P Padley, N Parashar, S-J Park, SK Park, J Parsons, R Partridge, N Parua, A Patwa, G Pawloski, PM Perea, E Perez, K Peters, P Pétroff, M Petteni, R Piegaia, J Piper, M-A Pleier, PLM Podesta-Lerma, VM Podstavkov, Y Pogorelov, M-E Pol, A Pompos, BG Pope, AV Popov, C Potter, WL Prado da Silva, HB Prosper, S Protopopescu, J Qian, A Quadt, B Quinn, MS Rangel, KJ Rani, K Ranjan, PN Ratoff, P Renkel, S Reucroft, M Rijssenbeek, I Ripp-Baudot, F Rizatdinova, S Robinson, RF Rodrigues, C Royon, P Rubinov, R Ruchti, VI Rud, G Sajot, A Sánchez-Hernández, MP Sanders, A Santoro, G Savage, L Sawyer, T Scanlon, D Schaile, RD Schamberger, Y Scheglov, H Schellman, P Schieferdecker, C Schmitt, C Schwanenberger, A Schwartzman, R Schwienhorst, J Sekaric, S Sengupta, H Severini, E Shabalina, M Shamim, V Shary, AA Shchukin, WD Shephard, RK Shivpuri, D Shpakov, V Siccardi, RA Sidwell, V Simak, V Sirotenko, P Skubic, P Slattery, RP Smith, GR Snow, J Snow, S Snyder, S Söldner-Rembold, X Song, L Sonnenschein, A Sopczak, M Sosebee, K Soustruznik, M Souza, B Spurlock, J Stark, J Steele, V Stolin, A Stone, DA Stoyanova, J Strandberg, S Strandberg, MA Strang, M Strauss, R Ströhmer, D Strom, M Strovink, L Stutte, S Sumowidagdo, A Sznajder, M Talby, P Tamburello, W Taylor, P Telford, J Temple, B Tiller, M Titov, VV Tokmenin, M Tomoto, T Toole, I Torchiani, S Towers, T Trefzger, S Trincaz-Duvoid, D Tsybychev, B Tuchming, C Tully, AS Turcot, PM Tuts, R Unalan, L Uvarov, S Uvarov, S Uzunyan, B Vachon, PJ van den Berg, R Van Kooten, WM van Leeuwen, N Varelas, EW Varnes, A Vartapetian, IA Vasilyev, M Vaupel, P Verdier, LS Vertogradov, M Verzocchi, F Villeneuve-Seguier, P Vint, J-R Vlimant, E Von Toerne, M Voutilainen, M Vreeswijk, HD Wahl, L Wang, MHLS Wang, J Warchol, G Watts, M Wayne, M Weber, H Weerts, N Wermes, M Wetstein, A White, D Wicke, GW Wilson, SJ Wimpenny, M Wobisch, J Womersley, DR Wood, TR Wyatt, Y Xie, N Xuan, S Yacoob, R Yamada, M Yan, T Yasuda, YA Yatsunenko, K Yip, HD Yoo, SW Youn, C Yu, J Yu, A Yurkewicz, A Zatserklyaniy, C Zeitnitz, D Zhang, T Zhao, B Zhou, J Zhu, M Zielinski, D Zieminska, A Zieminski, V Zutshi, EG Zverev

Abstract:

We present the first experimental discrimination between the 2e/3 and 4e/3 top quark electric charge scenarios, using top quark pairs (tt) produced in pp collisions at (square root) s = 1.96 TeV by the Fermilab Tevatron Collider. We use 370 pb;{-1} of data collected by the D0 experiment and select events with at least one high transverse momentum electron or muon, high transverse energy imbalance, and four or more jets. We discriminate between b- and b-quark jets by using the charge and momenta of tracks within the jet cones. The data are consistent with the expected electric charge, |q|=2e/3. We exclude, at the 92% C.L., that the sample is solely due to the production of exotic quark pairs QQ with |q|=4e/3. We place an upper limit on the fraction of QQ pairs rho<0.80 at the 90% C.L.

Charge-Separated Atmospheric Neutrino-Induced Muons in the MINOS Far Detector

ArXiv hep-ex/0701045 (2007)

Measurement of the production cross-section of positive pions in the collision of 8.9 GeV/c protons on beryllium

European Physical Journal C 52:1 (2007) 29-53

Authors:

MG Catanesi, E Radicioni, R Edgecock, M Ellis, S Robbins, FJP Soler, C Gößling, S Bunyatov, G Chelkov, D Dedovitch, M Gostkin, A Guskov, D Khartchenko, A Krasnoperov, Z Kroumchtein, Y Nefedov, B Popov, V Serdiouk, V Tereshchenko, A Zhemchugov, E Di Capua, G Vidal-Sitjes, A Artamonov, P Arce, S Giani, S Gilardoni, P Gorbunov, A Grant, A Grossheim, P Gruber, V Ivanchenko, A Kayis-Topaksu, J Panman, I Papadopoulos, J Pasternak, E Tcherniaev, I Tsukerman, R Veenhof, C Wiebusch, P Zucchelli, A Blondel, S Borghi, M Campanelli, MC Morone, G Prior, R Schroeter, R Engel, C Meurer, I Kato, U Gastaldi, GB Mills, JS Graulich, G Grégoire, M Bonesini, A De Min, F Ferri, M Paganoni, F Paleari, M Kirsanov, A Bagulya, V Grichine, N Polukhina, V Palladino, L Coney, D Schmitz, G Barr, A De Santo, C Pattison, K Zuber, F Bobisut, D Gibin, A Guglielmi, M Mezzetto, J Dumarchez, F Vannucci, V Ammosov, V Koreshev, A Semak, V Zaets, U Dore, D Orestano, F Pastore, A Tonazzo, L Tortora, C Booth, C Buttar, P Hodgson, L Howlett, M Bogomilov, M Chizhov, D Kolev, R Tsenov, S Piperov, P Temnikov, M Apollonio, P Chimenti, G Giannini, G Santin, J Burguet-Castell, A Cervera-Villanueva

Abstract:

The double-differential production cross-section of positive pions, d 2σπ+/d pdΩ, measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with a thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75∈GeV/c≤pπ≤ 6.5∈GeV/c and 30∈mrad≤θπ≤ 210∈mrad in the laboratory frame. © 2007 Springer-Verlag / Società Italiana di Fisica.