Dijet angular distributions in photoproduction of charm at HERA

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 565:1-4 (2003) 87-101

Authors:

S Chekanov, M Derrick, D Krakauer, JH Loizides, S Magill, B Musgrave, 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, A Margotti, R Nania, F Palmonari, A Pesci, G Sartorelli, A Zichichi, G Aghuzumtsyan, D Bartsch, I Brock, S Goers, H Hartmann, E Hilger, P Irrgang, HP Jakob, A Kappes, UF Katz, O Kind, U Meyer, E Paul, J Rautenberg, R Renner, A Stifutkin, J Tandler, KC Voss, M Wang, A Weber, 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, JY Kim, YK Kim, JH Lee, IT Lim, MY Pac, A Caldwell, M Helbich, X Liu, B Mellado, Y Ning, S Paganis, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, K Olkiewicz, P Stopa, L Zawiejski, L Adamczyk, T Bold, I Grabowska-Bold, D Kisielewska, AM Kowal, M Kowal, T Kowalski, M Przybycien, L Suszycki, D Szuba, J Szuba, A Kota艅ski, W Slomi艅ski, LAT Bauerdick, U Behrens

Abstract:

Dijet angular distributions of photoproduction events in which a D*卤 meson is produced in association with one of two energetic jets have been measured with the ZEUS detector at HERA, using an integrated luminosity of 120 pb-1. Differential cross sections as a function of the angle between the charm-jet and the proton-beam direction in the dijet rest frame have been measured for samples enriched in direct or resolved photon events. The results are compared with predictions from leading-order parton-shower Monte Carlo models and with next-to-leading-order QCD calculations. The angular distributions show clear evidence for the existence of charm originating from the photon. 漏 2003 Published by Elsevier B.V.

Search for lepton flavor violating decays of a heavy neutral particle in p-pbar collisions at root(s)=1.8 TeV

ArXiv hep-ex/0307012 (2003)

Authors:

The CDF Collaboration, D Acosta

Central pseudorapidity gaps in events with a leading antiproton at the fermilab tevatron pp collider.

Phys Rev Lett 91:1 (2003) 011802

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, A Bolshov, 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, L Cerrito, 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, W-H 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, S De Cecco, F DeJongh, S Dell'Agnello, M Dell'Orso, S Demers, L Demortier, M Deninno, D De Pedis, PF Derwent, T Devlin, C Dionisi, JR Dittmann, A Dominguez, S Donati, M D'Onofrio, T Dorigo, N Eddy, K Einsweiler, E Engels, R Erbacher, D Errede, S Errede, R Eusebi, Q Fan, H-C Fang, S Farrington, RG Feild, JP Fernandez, C Ferretti, RD Field, I Fiori, B Flaugher, LR Flores-Castillo, 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, E Gerstein, S Giagu, P Giannetti, K Giolo, M Giordani, V Glagolev, D Glenzinski, M Gold, N Goldschmidt, J Goldstein, G Gomez, M Goncharov, I Gorelov, AT Goshaw, Y Gotra, K Goulianos, C Green, A Gresele, G Grim, C Grosso-Pilcher, M Guenther, G Guillian, J Guimaraes Da Costa, RM Haas, C Haber, SR Hahn, E Halkiadakis, C Hall, T Handa, R Handler, F Happacher, K Hara, AD Hardman, RM Harris, F Hartmann, K Hatakeyama, J Hauser, J Heinrich, A Heiss, M Hennecke, M Herndon, C Hill, A Hocker, KD Hoffman, R Hollebeek, L Holloway, S Hou, BT Huffman, R Hughes, J Huston, J Huth, H Ikeda, C Issever, J Incandela, G Introzzi, M Iori, A Ivanov, J Iwai, Y Iwata, B Iyutin, E James, M Jones, U Joshi, H Kambara, T Kamon, T Kaneko, J Kang, M Karagoz Unel, K Karr, S Kartal, H Kasha, Y Kato, TA Keaffaber, K Kelley, M Kelly, RD Kennedy, R Kephart, D Khazins, T Kikuchi, B Kilminster, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, TH Kim, YK Kim, M Kirby, M Kirk, L Kirsch, S Klimenko, P Koehn, K Kondo, J Konigsberg, A Korn, A Korytov, K Kotelnikov, E Kovacs, J Kroll, M Kruse, V Krutelyov, SE Kuhlmann, K Kurino, T Kuwabara, N Kuznetsova, AT Laasanen, N Lai, S Lami, S Lammel, J Lancaster, K Lannon, M Lancaster, R Lander, A Lath, G Latino, T LeCompte, Y Le, J Lee, SW Lee, N Leonardo, S Leone, JD Lewis, K Li, CS Lin, M Lindgren, TM Liss, JB Liu, T Liu, YC Liu, DO Litvintsev, O Lobban, NS Lockyer, A Loginov, J Loken, M Loreti, D Lucchesi, P Lukens, S Lusin, L Lyons, J Lys, R Madrak, K Maeshima, P Maksimovic, L Malferrari, M Mangano, G Manca, M Mariotti, G Martignon, M Martin, A Martin, V Martin, M Mart铆nez, 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, R Napora, F Niell, C Nelson, T Nelson, C Neu, MS Neubauer, D Neuberger, C Newman-Holmes, C-YP Ngan, T Nigmanov, 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, T Pauly, C Paus, D Pellett, A Penzo, L Pescara, TJ Phillips, G Piacentino, J Piedra, KT Pitts, A Pompos, L Pondrom, G Pope, T Pratt, F Prokoshin, J Proudfoot, F Ptohos, O Pukhov, G Punzi, J Rademacker, A Rakitine, F Ratnikov, H Ray, D Reher, A Reichold, P Renton, M Rescigno, A Ribon, W Riegler, F Rimondi, L Ristori, WJ Robertson, T Rodrigo, S Rolli, L Rosenson, R Roser, R Rossin, C Rott, A Roy, A Ruiz, D Ryan, A Safonov, R St Denis, WK Sakumoto, D Saltzberg, C Sanchez, A Sansoni, L Santi, S Sarkar, H Sato, A Savoy-Navarro, P Schlabach, EE Schmidt, MP Schmidt, M Schmitt, L Scodellaro, A Scott, A Scribano, A Sedov, 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 Singh, AJ Slaughter, K Sliwa, FD Snider, R Snihur, A Solodsky, J Spalding, T Speer, M Spezziga, P Sphicas, F Spinella, M Spiropulu, L Spiegel, J Steele, A Stefanini, J Strologas, F Strumia, D Stuart, A Sukhanov, 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, J Thom, AS Thompson, E Thomson, R Thurman-Keup, P Tipton, S Tkaczyk, D Toback, K Tollefson, D Tonelli, M Tonnesmann, H Toyoda, JF De Troconiz, J Tseng, D Tsybychev, N Turini, F Ukegawa, T Unverhau, T Vaiciulis, J Valls, A Varganov, E Vataga, S Vejcik, G Velev, G Veramendi, R Vidal, I Vila, R Vilar, I Volobouev, M Von Der Mey, D Vucinic, RG Wagner, RL Wagner, W Wagner, NB Wallace, Z Wan, C Wang, MJ Wang, SM Wang, B Ward, S Waschke, T Watanabe, D Waters, T Watts, M Weber, H Wenzel, WC Wester, B Whitehouse, AB Wicklund, E Wicklund, T Wilkes, HH Williams, P Wilson, BL Winer, D Winn, S Wolbers, D Wolinski, J Wolinski, S Wolinski, M Wolter, S Worm, X Wu, F W眉rthwein, J Wyss, UK Yang, W Yao, GP Yeh, P Yeh, K Yi, J Yoh, C Yosef, T Yoshida, I Yu, S Yu, Z Yu, JC Yun, L Zanello, A Zanetti, F Zetti, S Zucchelli, CDF Collaboration

Abstract:

We report a measurement of the fraction of events with a large pseudorapidity gap deltaeta within the pseudorapidity region available to the proton dissociation products X in p+p-->p+X. For a final state p of fractional momentum loss xi(p) and 4-momentum transfer squared t(p) within 0.063 is found to be 0.246+/-0.001 (stat)+/-0.042 (syst) [0.184+/-0.001 (stat)+/-0.043 (syst)]. Our results are compared with gap fractions measured in minimum bias pp collisions and with theoretical expectations.

Search for the supersymmetric partner of the top quark in dilepton events from pp虅 collisions at 鈭歴 = 1.8 TeV

Physical Review Letters 90:25 I (2003) 2518011-2518017

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, A Bolshov, 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, L Cerrito, 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

Abstract:

The article discussed about the supersymmetric particles of the top quark in Dilepton events. The Collider Detector at Fermilab was used to gather supersymmetry particles. Due to the high mass, stop decays into the top quark were found kinematically inaccessible. The choice of the renormalization and factorization scale was considered as the source of uncertainty on the number of expected stop events.

Memorandum of Understanding for the 2002-2003 Meson Test Beam Program: The US-CMS Forward Pixel Group

Office of Scientific and Technical Information (OSTI) (2003)