High-mass dijet cross sections in photoproduction at HERA

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 531:1-2 (2002) 9-27

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, 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, D Bartsch, I Brock, J Crittenden, S Goers, H Hartmann, E Hilger, P Irrgang, HP Jakob, A Kappes, UF Katz, R Kerger, O Kind, E Paul, J Rautenberg, R Renner, H Schnurbusch, A Stifutkin, J Tandler, KC Voss, A Weber, H Wessoleck, 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, X Liu, B Mellado, S Paganis, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, K Olkiewicz, MB Przybycien, P Stopa, L Zawiejski, B Bednarek, I Grabowska-Bold, K Jeleń, D Kisielewska, AM Kowal, M Kowal, T Kowalski, B Mindur, E Rulikowska-Zarebska, L Suszycki, D Szuba

Abstract:

Dijet differential cross sections for the reaction e+ p → e+ + jet + jet + X in the photoproduction regime have been measured with the ZEUS detector at HERA using an integrated luminosity of 42.7 pb-. The cross sections are given for photon-proton centre-of-mass energies in the range 134 < W < 277 GeV. The differential cross sections as a function of the dijet mass, MJJ, and of the dijet angular variables have been measured for 47 < MJJ < 160 GeV and compared to next-to-leading-order QCD calculations. The dijet events in the region 75 < MJJ < 100 GeV have been used to derive a 95% C.L. upper limit on the cross section for Z0 photoproduction of σ e+p→e+Z0X < 5.9 pb. Upper limits on the photoproduction of new heavy resonances decaying into two jets are also presented for masses in the range between 60 GeV and 155 GeV. © 2002 Elsevier Science B.V. All rights reserved.

Dijet photoproduction at HERA and the structure of the photon

European Physical Journal C 23:4 (2002) 615-631

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, 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, D Bartsch, I Brock, J Crittenden, S Goers, H Hartmann, E Hilger, P Irrgang, HP Jakob, A Kappes, UF Katz, R Kerger, O Kind, E Paul, J Rautenberg, R Renner, H Schnurbusch, A Stifutkin, J Tandler, KC Voss, A Weber, H Wessoleck, 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, X Liu, B Mellado, S Paganis, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, 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, E Rulikowska-Zarȩbska, L Suszycki, D Szuba

Abstract:

The dijet cross section in photoproduction has been measured with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb-1. The events were required to have a virtuality of the incoming photon, Q2, of less than 1 GeV2 and a photon-proton centre-of-mass energy in the range 134 < Wγp < 277 GeV. Each event contains at least two jets satisfying transverse-energy requirements of ETjet1 > 14 GeV and ETjet2 > 11 GeV and pseudorapidity requirements of -1 < ηjet1,2 < 2.4. The measurements are compared to next-to-leading-order QCD predictions. The data show particular sensitivity to the density of partons in the photon, allowing the validity of the current parameterisations to be tested.

Soft and hard interactions in pp¯ collisions at s=1800 and 630 GeV

Physical Review D American Physical Society (APS) 65:7 (2002) 072005

Authors:

D Acosta, T Affolder, H Akimoto, MG Albrow, P Amaral, 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, 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, M-T 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, S D’Auria, F DeJongh, S Dell’Agnello, M Dell’Orso, S Demers, L Demortier, M Deninno, PF Derwent, T Devlin, JR Dittmann, A Dominguez, S Donati, J Done, M D’Onofrio, T Dorigo, N Eddy, K Einsweiler, JE Elias, E Engels, R Erbacher, D Errede, S Errede, Q Fan, H-C Fang, RG Feild, JP Fernandez, C Ferretti, RD Field, I Fiori, B Flaugher, GW Foster, M Franklin, J Freeman, J Friedman, Y Fukui, I Furic, S Galeotti, A Gallas, M Gallinaro, T Gao, M Garcia-Sciveres, AF Garfinkel, P Gatti, C Gay, DW Gerdes, P Giannetti, P Giromini, V Glagolev, D Glenzinski, M Gold, J Goldstein, I Gorelov, AT Goshaw, Y Gotra, K Goulianos, C Green, G Grim, P Gris, C Grosso-Pilcher, M Guenther, G Guillian, J Guimaraes da Costa, RM Haas, C Haber, SR Hahn, C Hall, T Handa, R Handler, W Hao, F Happacher, K Hara, AD Hardman, RM Harris, F Hartmann, K Hatakeyama, J Hauser, J Heinrich, A Heiss, M Herndon, C Hill, A Hocker, KD Hoffman, R Hollebeek, L Holloway, BT Huffman, R Hughes, J Huston, J Huth, H Ikeda, J Incandela, G Introzzi, A Ivanov, J Iwai, Y Iwata, E James, M Jones, U Joshi, H Kambara, T Kamon, T Kaneko, M Karagoz Unel, K Karr, S Kartal, H Kasha, Y Kato, TA Keaffaber, K Kelley, M Kelly, D Khazins, T Kikuchi, B Kilminster, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kim, M Kirby, M Kirk, L Kirsch, S Klimenko, P Koehn, K Kondo, J Konigsberg, A Korn, A Korytov, E Kovacs, J Kroll, M Kruse, SE Kuhlmann, K Kurino, T Kuwabara, AT Laasanen, N Lai, S Lami, S Lammel, J Lancaster, M Lancaster, R Lander, A Lath, G Latino, T LeCompte, K Lee, S Leone, JD Lewis, M Lindgren, TM Liss, JB Liu, YC Liu, DO Litvintsev, O Lobban, NS Lockyer, J Loken, M Loreti, D Lucchesi, P Lukens, S Lusin, L Lyons, J Lys, R Madrak, K Maeshima, P Maksimovic, L Malferrari, M Mangano, M Mariotti, G Martignon, A Martin, JAJ Matthews, P Mazzanti, KS McFarland, P McIntyre, M Menguzzato, A Menzione, P Merkel, C Mesropian, A Meyer, T Miao, R Miller, JS Miller, H Minato, S Miscetti, M Mishina, G Mitselmakher, Y Miyazaki, N Moggi, E Moore, R Moore, Y Morita, T Moulik, M Mulhearn, A Mukherjee, T Muller, A Munar, P Murat, S Murgia, J Nachtman, V Nagaslaev, S Nahn, H Nakada, I Nakano, C Nelson, T Nelson, C Neu, D Neuberger, C Newman-Holmes, C-YP Ngan, H Niu, L Nodulman, A Nomerotski, SH Oh, YD Oh, T Ohmoto, T Ohsugi, R Oishi, T Okusawa, J Olsen, W Orejudos, C Pagliarone, F Palmonari, R Paoletti, V Papadimitriou, D Partos, J Patrick, G Pauletta, M Paulini, C Paus, D Pellett, L Pescara, TJ Phillips, G Piacentino, KT Pitts, A Pompos, L Pondrom, G Pope, F Prokoshin, J Proudfoot, F Ptohos, O Pukhov, G Punzi, A Rakitine, F Ratnikov, D Reher, A Reichold, P Renton, A Ribon, W Riegler, F Rimondi, L Ristori, M Riveline, WJ Robertson, T Rodrigo, S Rolli, L Rosenson, R Roser, R Rossin, C Rott, A Roy, A Ruiz, A Safonov, R St. Denis, WK Sakumoto, D Saltzberg, C Sanchez, A Sansoni, L Santi, H Sato, P Savard, A Savoy-Navarro, P Schlabach, EE Schmidt, MP Schmidt, M Schmitt, L Scodellaro, A Scott, A Scribano, A Sedov, S Segler, S Seidel, Y Seiya, A Semenov, F Semeria, T Shah, MD Shapiro, PF Shepard, T Shibayama, M Shimojima, M Shochet, A Sidoti, J Siegrist, A Sill, P Sinervo, P Singh, AJ Slaughter, K Sliwa, C Smith, FD Snider, A Solodsky, J Spalding, T Speer, P Sphicas, F Spinella, M Spiropulu, L Spiegel, J Steele, A Stefanini, J Strologas, F Strumia, D Stuart, K Sumorok, T Suzuki, T Takano, R Takashima, K Takikawa, P Tamburello, M Tanaka, B Tannenbaum, M Tecchio, RJ Tesarek, PK Teng, K Terashi, S Tether, AS Thompson, E Thomson, R Thurman-Keup, P Tipton, S Tkaczyk, D Toback, K Tollefson, A Tollestrup, D Tonelli, H Toyoda, W Trischuk, JF de Troconiz, J Tseng, D Tsybychev, N Turini, F Ukegawa, T Vaiciulis, J Valls, S Vejcik, G Velev, G Veramendi, R Vidal, I Vila, R Vilar, I Volobouev, M von der Mey, D Vucinic, RG Wagner, RL Wagner, NB Wallace, Z Wan, C Wang, MJ Wang, SM Wang, B Ward, S Waschke, T Watanabe, D Waters, T Watts, R Webb, H Wenzel, WC Wester, AB Wicklund, E Wicklund, T Wilkes, HH Williams, P Wilson, BL Winer, D Winn, S Wolbers, D Wolinski, J Wolinski, S Wolinski, S Worm, X Wu, J Wyss, W Yao, GP Yeh, P Yeh, J Yoh, C Yosef, T Yoshida, I Yu, S Yu, Z Yu, A Zanetti, F Zetti, S Zucchelli

Direct search for charged higgs bosons in decays of top quarks.

Physical review letters 88:15 (2002) 151803

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 de Jong, K Del Signore, M Demarteau, R Demina, P Demine, D Denisov, SP Denisov, S Desai, HT Diehl, M Diesburg, G Di Loreto, S Doulas, P Draper, Y Ducros, LV Dudko, S Duensing, L Duflot, SR Dugad, A Dyshkant, D Edmunds, J Ellison, VD Elvira, R Engelmann, S Eno, G Eppley, P Ermolov, OV Eroshin, J Estrada, H Evans, VN Evdokimov, T Fahland, S Feher, D Fein, T Ferbel, F Filthaut, HE Fisk, Y Fisyak, E Flattum, F Fleuret, M Fortner, KC Frame, S Fuess, E Gallas, AN Galyaev, M Gao, V Gavrilov, RJ Genik, K Genser, CE Gerber, Y Gershtein, R Gilmartin, G Ginther, B Gómez, G Gómez, PI Goncharov, JL González Solís, H Gordon, LT Goss, K Gounder, A Goussiou, N Graf, G Graham, PD Grannis, JA Green, H Greenlee, S Grinstein, L Groer, S Grünendahl, A Gupta, SN Gurzhiev, G Gutierrez, P Gutierrez, NJ Hadley, H Haggerty, S Hagopian, V Hagopian, RE Hall, P Hanlet, S Hansen, JM Hauptman, C Hays, C Hebert, D Hedin, AP Heinson, U Heintz, T Heuring, MD Hildreth, R Hirosky, JD Hobbs, B Hoeneisen, Y Huang, R Illingworth, AS Ito, M Jaffré, S Jain, R Jesik, K Johns, M Johnson, A Jonckheere, M Jones, H Jöstlein, A Juste, S Kahn, E Kajfasz, AM Kalinin, D Karmanov, D Karmgard, R Kehoe, A Kharchilava, SK Kim, B Klima, B Knuteson, W Ko, JM Kohli, AV Kostritskiy, J Kotcher, AV Kotwal, AV Kozelov, EA Kozlovsky, J Krane, MR Krishnaswamy, P Krivkova, S Krzywdzinski, M Kubantsev, S Kuleshov, Y Kulik, S Kunori, A Kupco, VE Kuznetsov, G Landsberg, A Leflat, C Leggett, F Lehner, J Li, QZ Li, JGR Lima, D Lincoln, SL Linn, J Linnemann, R Lipton, A Lucotte, L Lueking, C Lundstedt, C Luo, AKA Maciel, RJ Madaras, VL Malyshev, V Manankov, HS Mao, T Marshall, MI Martin, RD Martin, KM Mauritz, B May, AA Mayorov, R McCarthy, J McDonald, T McMahon, HL Melanson, M Merkin, KW Merritt, C Miao, H Miettinen, D Mihalcea, CS Mishra, N Mokhov, NK Mondal, HE Montgomery, RW Moore, M Mostafa, H da Motta, E Nagy, F Nang, M Narain, VS Narasimham, HA Neal, JP Negret, S Negroni, T Nunnemann, D O'Neil, V Oguri, B Olivier, N Oshima, P Padley, LJ Pan, K Papageorgiou, A Para, N Parashar, R Partridge, N Parua, M Paterno, A Patwa, B Pawlik, J Perkins, M Peters, O Peters, P Pétroff, R Piegaia, H Piekarz, BG Pope, E Popkov, HB Prosper, S Protopopescu, J Qian, R Raja, S Rajagopalan, E Ramberg, PA Rapidis, NW Reay, S Reucroft, J Rha, M Ridel, M Rijssenbeek, T Rockwell, M Roco, P Rubinov, R Ruchti, J Rutherfoord, BM Sabirov, A Santoro, L Sawyer, RD Schamberger, H Schellman, A Schwartzman, N Sen, E Shabalina, RK Shivpuri, D Shpakov, M Shupe, RA Sidwell, V Simak, H Singh, JB Singh, V Sirotenko, P Slattery, E Smith, RP Smith, R Snihur, GR Snow, J Snow, S Snyder, J Solomon, V Sorín, M Sosebee, N Sotnikova, K Soustruznik, M Souza, NR Stanton, G Steinbrück, RW Stephens, F Stichelbaut, D Stoker, V Stolin, DA Stoyanova, M Strauss, M Strovink, L Stutte, A Sznajder, W Taylor, S Tentindo-Repond, SM Tripathi, TG Trippe, AS Turcot, PM Tuts, P van Gemmeren, V Vaniev, R Van Kooten, N Varelas, LS Vertogradov, AA Volkov, AP Vorobiev, HD Wahl, H Wang, Z-M Wang, J Warchol, G Watts, M Wayne, H Weerts, A White, JT White, D Whiteson, JA Wightman, DA Wijngaarden, S Willis, SJ Wimpenny, J Womersley, DR Wood, R Yamada, P Yamin, T Yasuda, YA Yatsunenko, K Yip, S Youssef, J Yu, Z Yu, M Zanabria, H Zheng, Z Zhou, M Zielinski, D Zieminska, A Zieminski, V Zutshi, EG Zverev, A Zylberstejn, D0 Collaboration

Abstract:

We present a search for charged Higgs bosons in decays of pair-produced top quarks in pp collisions at sqrt[s] = 1.8 TeV recorded by the D0 detector at the Fermilab Tevatron collider. With no evidence for signal, we exclude most regions of the ( M(H+/-),tan(beta)) parameter space where the decay t--> H(+)b has a branching fraction >0.36 and B(H+/--->tau(nu)(tau)) is large.

Single event upset studies with the optical links of the ATLAS semiconductor tracker

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 481 (2002) 575-584

Authors:

AR Weidberg, J.D. Dowell, R.J. Homer, G. Mahout