Measurement of the diffractive structure function FD(4) 2 at HERA

European Physical Journal C 1:1-2 (1998) 81-96

Authors:

J Breitweg, M Derrick, D Krakauer, S Magill, D Mikunas, B Musgrave, J Repond, R Stanek, RL Talaga, R Yoshida, H Zhang, MCK Mattingly, F Anselmo, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, G Cara Romeo, G Castellini, M Chiarini, L Cifarelli, F Cindolo, A Contin, M Corradi, S de Pasquale, I Gialas, P Giusti, G Iacobucci, G Laurenti, G Levi, A Margotti, T Massam, R Nania, C Nemoz, F Palmonari, A Pesci, A Polini, F Ricci, G Sartorelli, Y Zamora Garcia, A Zichichi, C Amelung, A Bornheim, I Brock, K Coböken, J Crittenden, R Deffner, M Eckert, M Grothe, H Hartmann, K Heinloth, L Heinz, E Hilger, HP Jakob, UF Katz, R Kerger, E Paul, M Pfeiffer, C Rembser, J Stamm, R Wedemeyer, H Wieber, DS Bailey, S Campbell-Robson, WN Cottingham, B Foster, R Hall-Wilton, ME Hayes, GP Heath, HF Heath, JD McFall, D Piccioni, DG Roff, RJ Tapper, M Arneodo, R Ayad, M Capua, A Garfagnini, L Iannotti, M Schioppa, G Susinno, JY Kim, JH Lee, IT Lim, MY Pac, A Caldwell, N Cartiglia, Z Jing, W Liu, B Mellado, JA Parsons, S Ritz, S Sampson, F Sciulli, PB Straub, Q Zhu, P Borzemski

Abstract:

This paper presents the first analysis of diffractive photon dissociation events in deep inelastic positron-proton scattering at HERA in which the proton in the final state is detected and its momentum measured. The events are selected by requiring a scattered proton in the ZEUS leading proton spectrometer (LPS) with xL > 0.97, where xL is the fraction of the incoming proton beam momentum carried by the scattered proton. The use of the LPS significantly reduces the contamination from events with diffractive dissociation of the proton into low mass states and allows a direct measurement of t, the square of the four-momentum exchanged at the proton vertex. The dependence of the cross section on t is measured in the interval 0.073 < \t\ < 0.4 GeV2 and is found to be described by an exponential shape with the slope parameter b = 7.2 ± 1.1(stat.)+0.7 -0.9(syst.) GeV-2. The diffractive structure function FD(4) 2 is presented as a function of xIP, ≃ 1 - xL and β, the momentum fraction of the struck quark with respect to xIP, and averaged over the t interval 0.073 < \t\ < 0.4 GeV2 and the photon virtuality range 5 < Q2 < 20 GeV2. In the kinematic range 4 x 10-4 < xIP < 0.03 and 0.015 < β < 0.5, the xIP dependence of FD(4) 2 is fitted with a form (1/xIP)a , yielding a = 1.00 ± 0.09 (stat.)+0.11 -0.05(syst.). Upon integration over t, the structure function FD(3) 2 is determined in a kinematic range extending to higher xIP and lower β compared to our previous analysis; the results are discussed within the framework of Regge theory.

Measurement of the t distribution in diffractive photoproduction at HERA

European Physical Journal C 2:2 (1998) 237-246

Authors:

J Breitweg, M Derrick, D Krakauer, S Magill, D Mikunas, B Musgrave, J Repond, R Stanek, RL Talaga, R Yoshida, H Zhang, MCK Mattingly, F Anselmo, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, G Cara Romeo, G Castellini, M Chiarini, L Cifarelli, F Cindolo, A Contin, M Corradi, S de Pasquale, I Gialas, P Giusti, G Iacobucci, G Laurenti, G Levi, A Margotti, T Massam, R Nania, C Nemoz, F Palmonari, A Pesci, A Polini, F Ricci, G Sartorelli, Y Zamora Garcia, A Zichichi, C Amelung, A Bornheim, I Brock, K Coböken, J Crittenden, R Deffner, M Eckert, M Grothe, H Hartmann, K Heinloth, L Heinz, E Hilger, HP Jakob, UF Katz, R Kerger, E Paul, M Pfeiffer, C Rembser, J Stamm, R Wedemeyer, H Wieber, DS Bailey, S Campbell-Robson, WN Cottingham, B Foster, R Hall-Wilton, ME Hayes, GP Heath, HF Heath, JD McFall, D Piccioni, DG Roff, RJ Tapper, M Arneodo, R Ayad, M Capua, A Garfagnini, L Iannotti, M Schioppa, G Susinno, JY Kim, JH Lee, IT Lim, MY Pac, A Caldwell, N Cartiglia, Z Jing, W Liu, B Mellado, JA Parsons, S Ritz, S Sampson, F Sciulli, PB Straub, Q Zhu, P Borzemski

Abstract:

Photon diffractive dissociation, γp → Xp, has been studied at HERA with the ZEUS detector using ep interactions where the virtuality Q2 of the exchanged photon is smaller than 0.02 GeV2. The squared four-momentum t exchanged at the proton vertex was determined in the range 0.073 < \t\ < 0.40 GeV2 by measuring the scattered proton in the ZEUS Leading Proton Spectrometer. In the photonproton centre-of-mass energy interval 176 < W < 225 GeV and for masses of the dissociated photon system 4 < Mx < 32 GeV, the t distribution has an exponential shape, dN/d\t\ ∝ exp (-b\t\), with a slope parameter b = 6.8 ± 0.9 (stat.) +1.2-1.1 (syst.) GeV-2.

Observation of B+-ψ(2S)K+ and B0-ψ(2S)K*(892)0 decays and measurements of B-meson branching fractions into J/ψ and ψ(2S) final states

Physical Review D 58:7 (1998) 0720011-07200115

Authors:

F Abe, H Akimoto, A Akopian, MG Albrow, A Amadon, SR Amendolia, D Amidei, J Antos, S Aota, G Apollinari, T Arisawa, T Asakavva, W Ashmanskas, M Atac, P Azzi-Bacchetta, N Bacchetta, S Bagdasarov, MW Bailey, P De Barbara, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, T Baumann, F Bedeschi, S Behrends, S Belferte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, S Bertolucci, S Bettelli, B Bevensee, A Bhatti, K Biery, C Bigongiari, M Binkley, D Bisello, RE Blair, C Blocker, S Blusk, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, L Breccia, C Bromberg, N Bruner, R Brunetti, E Buckley-Geer, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, M Campbell, A Caner, W Carithers, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, PS Chang, PT Chang, HY Chao, J Chapman, MT Cheng, M Chertok, G Chiarelli, CN Chiou, F Chlebana, L Christofek, ML Chu, S Cihangir, AG Clark, M Cobal, E Cocca, M Contreras, J Conway, J Cooper, M Cordelli, D Costanzo, C Couyoumtzelis, D Cronin-Hennessy, R Culbertson, D Dagenhart, T Daniels, F Dejongh, S Dell'Agnello, M Dell'Orso

Properties of photon plus two-jet events in p¯p collisions at s=1.8 TeV

Physical Review D American Physical Society (APS) 57:1 (1998) 67-77

Authors:

F Abe, H Akimoto, A Akopian, MG Albrow, SR Amendolia, D Amidei, J Antos, S Aota, G Apollinari, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, W Badgett, S Bagdasarov, MW Bailey, J Bao, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, E Barzi, G Bauer, T Baumann, F Bedeschi, S Behrends, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Benlloch, J Bensinger, D Benton, A Beretvas, JP Berge, J Berryhill, S Bertolucci, B Bevensee, A Bhatti, K Biery, M Binkley, D Bisello, RE Blair, C Blocker, A Bodek, W Bokhari, V Bolognesi, G Bolla, D Bortoletto, J Boudreau, L Breccia, C Bromberg, N Bruner, E Buckley-Geer, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, J Cammerata, C Campagnari, M Campbell, A Caner, W Carithers, D Carlsmith, A Castro, D Cauz, Y Cen, F Cervelli, PS Chang, PT Chang, HY Chao, J Chapman, M-T Cheng, G Chiarelli, T Chikamatsu, CN Chiou, L Christofek, S Cihangir, AG Clark, M Cobal, E Cocca, M Contreras, J Conway, J Cooper, M Cordelli, C Couyoumtzelis, D Crane, D Cronin-Hennessy, R Culbertson, T Daniels, F DeJongh, S Delchamps, S Dell’Agnello, M Dell’Orso, R Demina, L Demortier, M Deninno, PF Derwent, T Devlin, JR Dittmann, S Donati, J Done, T Dorigo, A Dunn, N Eddy, K Einsweiler, JE Elias, R Ely, E Engels, D Errede, S Errede, Q Fan, G Feild, C Ferretti, I Fiori, B Flaugher, GW Foster, M Franklin, M Frautschi, J Freeman, J Friedman, H Frisch, Y Fukui, S Funaki, S Galeotti, M Gallinaro, O Ganel, M Garcia-Sciveres, AF Garfinkel, C Gay, S Geer, DW Gerdes, P Giannetti, N Giokaris, P Giromini, G Giusti, L Gladney, D Glenzinski, M Gold, J Gonzalez, A Gordon, AT Goshaw, Y Gotra, K Goulianos, H Grassmann, L Groer, C Grosso-Pilcher, G Guillian, RS Guo, C Haber, E Hafen, SR Hahn, R Hamilton, R Handler, RM Hans, F Happacher, K Hara, AD Hardman, B Harral, RM Harris, SA Hauger, J Hauser, C Hawk, E Hayashi, J Heinrich, B Hinrichsen, KD Hoffman, M Hohlmann, C Holck, R Hollebeek, L Holloway, S Hong, G Houk, P Hu, BT Huffman, R Hughes, J Huston, J Huth, J Hylen, H Ikeda, M Incagli, J Incandela, G Introzzi, J Iwai, Y Iwata, H Jensen, U Joshi, RW Kadel, E Kajfasz, H Kambara, T Kamon, T Kaneko, K Karr, H Kasha, Y Kato, TA Keaffaber, K Kelley, RD Kennedy, R Kephart, P Kesten, D Kestenbaum, H Keutelian, F Keyvan, B Kharadia, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kim, L Kirsch, P Koehn, K Kondo, J Konigsberg, S Kopp, K Kordas, A Korytov, W Koska, E Kovacs, W Kowald, M Krasberg, J Kroll, M Kruse, T Kuwabara, SE Kuhlmann, E Kuns, AT Laasanen, S Lami, S Lammel, JI Lamoureux, M Lancaster, T LeCompte, S Leone, JD Lewis, P Limon, M Lindgren, TM Liss, JB Liu, YC Liu, N Lockyer, O Long, C Loomis, M Loreti, J Lu, D Lucchesi, P Lukens, S Lusin, J Lys, K Maeshima, A Maghakian, P Maksimovic, M Mangano, J Mansour, M Mariotti, JP Marriner, A Martin, JAJ Matthews, R Mattingly, P McIntyre, P Melese, A Menzione, E Meschi, S Metzler, C Miao, T Miao, G Michail, R Miller, H Minato, S Miscetti, M Mishina, H Mitsushio, T Miyamoto, S Miyashita, N Moggi, Y Morita, A Mukherjee, T Muller, P Murat, H Nakada, I Nakano, C Nelson, D Neuberger, C Newman-Holmes, C-YP Ngan, M Ninomiya, L Nodulman, SH Oh, KE Ohl, T Ohmoto, T Ohsugi, R Oishi, M Okabe, T Okusawa, R Oliveira, J Olsen, C Pagliarone, R Paoletti, V Papadimitriou, SP Pappas, N Parashar, S Park, A Parri, J Patrick, G Pauletta, M Paulini, A Perazzo, L Pescara, MD Peters, TJ Phillips, G Piacentino, M Pillai, KT Pitts, R Plunkett, L Pondrom, J Proudfoot, F Ptohos, G Punzi, K Ragan, D Reher, A Ribon, F Rimondi, L Ristori, WJ Robertson, T Rodrigo, S Rolli, J Romano, L Rosenson, R Roser, T Saab, WK Sakumoto, D Saltzberg, A Sansoni, L Santi, H Sato, P Schlabach, EE Schmidt, MP Schmidt, A Scribano, S Segler, S Seidel, Y Seiya, G Sganos, MD Shapiro, NM Shaw, Q Shen, PF Shepard, M Shimojima, M Shochet, J Siegrist, A Sill, P Sinervo, P Singh, J Skarha, K Sliwa, FD Snider, T Song, J Spalding, T Speer, P Sphicas, F Spinella, M Spiropulu, L Spiegel, L Stanco, J Steele, A Stefanini, K Strahl, J Strait, R Ströhmer, D Stuart, G Sullivan, K Sumorok, J Suzuki, T Takada, T Takahashi, T Takano, K Takikawa, N Tamura, B Tannenbaum, F Tartarelli, W Taylor, PK Teng, Y Teramoto, S Tether, D Theriot, TL Thomas, R Thun, R Thurman-Keup, M Timko, P Tipton, A Titov, S Tkaczyk, D Toback, K Tollefson, A Tollestrup, H Toyoda, W Trischuk, JF de Troconiz, S Truitt, J Tseng, N Turini, T Uchida, N Uemura, F Ukegawa, G Unal, J Valls, SC van den Brink, S Vejcik, G Velev, R Vidal, R Vilar, M Vondracek, D Vucinic, RG Wagner, RL Wagner, J Wahl, NB Wallace, AM Walsh, C Wang, CH Wang, J Wang, MJ Wang, QF Wang, A Warburton, T Watts, R Webb, C Wei, H Wenzel, WC Wester, AB Wicklund, E Wicklund, R Wilkinson, HH Williams, P Wilson, BL Winer, D Winn, D Wolinski, J Wolinski, S Worm, X Wu, J Wyss, A Yagil, W Yao, K Yasuoka, Y Ye, GP Yeh, P Yeh, M Yin, J Yoh, C Yosef, T Yoshida, D Yovanovitch, I Yu, L Yu, JC Yun, A Zanetti, F Zetti, L Zhang, W Zhang, S Zucchelli

Search for long-lived parents of Z° bosons inpp collisions at √s = 1.8 TeV

Physical Review D 58:5 (1998)

Authors:

F Abe, H Akimoto, A Akopian, MG Albrow, A Amadon, SR Amendolia, D Amidei, J Antos, S Aota, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, P Azzi-Bacchetta, N Bacchetta, S Bagdasarov, MW Bailey, P De Barbara, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, T Baumann, F Bedeschi, S Behrends, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, S Bertolucci, S Bettelli, B Bevensee, A Bhatti, K Biery, C Bigongiari, M Binkley, D Bisello, RE Blair, C Blocker, S Blusk, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, L Breccia, C Bromberg, N Bruner, R Brunetti, E Buckley-Geer, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, M Campbell, A Caner, W Carithers, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, PS Chang, PT Chang, HY Chao, J Chapman, MT Cheng, M Chertok, G Chiarelli, CN Chiou, F Chlebana, L Christofek, ML Chu, S Cihangir, AG Clark, M Cobal, E Cocca, M Contreras, J Conway, J Cooper, M Cordelli, D Costanzo, C Couyoumtzelis, D Cronin-Hennessy, R Culbertson, D Dagenhart, T Daniels, F Dejongh, S Dell'Agnello, M Dell'Orso

Abstract:

We search for new long-lived particles which decay to Z0 bosons by looking for Z0→e+e- decays with displaced vertices. We find no evidence for parent particles pf the Z0 with long lifetimes in 90 pb-1 of data from the CDF experiment at Fermilab. We set a cross section limit as a function of the lifetime of the parent particle for both a generic Z0 parent and a fourth-generation, charge -1/3 quark that decays into Z0b. © 1998 The American Physical Society.