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Search for R-parity violation with a Ū D̄ D̄ coupling at √s = 189 GeV

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 500:1-2 (2001) 22-36

Authors:

P Abreu, W Adam, T Adye, P Adzic, I Ajinenko, Z Albrecht, T Alderweireld, GD Alekseev, R Alemany, T Allmendinger, PP Allport, S Almehed, U Amaldi, N Amapane, S Amato, EG Anassontzis, P Andersson, A Andreazza, S Andringa, P Antilogus, WD Apel, Y Arnoud, B Åsman, JE Augustin, A Augustinus, P Baillon, A Ballestrero, P Bambade, F Barao, G Barbiellini, R Barbier, DY Bardin, G Barker, A Baroncelli, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, P Beilliere, Y Belokopytov, NC Benekos, AC Benvenuti, C Berat, M Berggren, L Berntzon, D Bertrand, M Besancon, MS Bilenky, MA Bizouard, D Bloch, HM Blom, M Bonesini, M Boonekamp, PSL Booth, G Borisov, C Bosio, O Botner, E Boudinov, B Bouquet, C Bourdarios, TJV Bowcock, I Boyko, I Bozovic, M Bozzo, M Bracko, P Branchini, RA Brenner, P Bruckman, JM Brunet, L Bugge, T Buran, B Buschbeck, P Buschmann, S Cabrera, M Caccia, M Calvi, T Camporesi, V Canale, F Carena, L Carroll, C Caso, MV Castillo Gimenez, A Cattai, FR Cavallo, P Charpentier, P Checchia, GA Chelkov, R Chierici, P Chliapnikov, P Chochula, V Chorowicz, J Chudoba, K Cieslik, P Collins, R Contri, E Cortina, G Cosme, F Cossutti, M Costa

Abstract:

Searches for pair production of gauginos and squarks in e+e- collisions at a centre-of-mass energy of 189 GeV have been performed on data corresponding to an integrated luminosity of 158 pb-1 collected by the DELPHI detector at LEP. The data were analyzed under the assumption of non-conservation of R-parity through a single dominant Ū D̄ D̄ coupling between squarks and quarks. Typical final states contain between 4 and 10 jets with or without additional leptons. No excess of data above Standard Model expectations was observed. The results were used to constrain domains of the MSSM parameter space and derive limits on the masses of supersymmetric particles. The following mass limits at 95% CL were obtained from these searches: neutralino mass: mx̃1/0 ≥ 32 GeV; chargino mass: mx̃1/+ ≥ 94 GeV; stop and sbottom mass (indirect decay) with δAM > 5 GeV: mt̃1 ≥ 74 GeV for φmix = 0 rad, mt̃1 ≥ 59 GeV for φmix = 0.98 rad, mb̃1 ≥ 72 GeV for φmix = 0 rad. The angle φmix is the mixing angle between left and right handed quarks. © 2001 Elsevier Science B.V.
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Prototype RICH detector using multi-anode photo multiplier tubes and hybrid photo-diodes

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 456:3 (2001) 233-247

Authors:

E Albrecht, G Barber, JH Bibby, NH Brook, G Doucas, A Duane, S Easo, L Eklund, M French, V Gibson, T Gys, AW Halley, N Harnew, M John, D Piedigrossi, J Rademacker, B Simmons, N Smale, P Teixeira-Dias, L Toudup, D Websdale, G Wilkingson, SA Wotton

Abstract:

The performance of a prototype Ring Imaging Cherenkov Detector is studied using a charged particle beam. The detector performance, using CF4 and air as radiators, is described. Cherenkov angle precision and photoelectron yield using hybrid photo-diodes and multi-anode PMTs agree with simulations and are assessed in terms of the requirements of the LHCb experiment.
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Search for the decay B+→D*+Ks0

Physical Review D 64:7 (2001)

Authors:

A Gritsan, JP Alexander, R Baker, C Bebek, BE Berger, K Berkelman, F Blanc, V Boisvert, DG Cassel, PS Drell, JE Duboseq, KM Ecklund, R Ehrlich, P Gaidarev, L Gibbons, B Gittelman, SW Gray, DL Hartill, BK Heltsley, PI Hopman, L Hsu, CD Jones, J Kandaswamy, DL Kreinick, M Lohner, A Magerkurth, TO Meyer, NB Mistry, E Nordberg, M Palmer, JR Patterson, D Peterson, D Riley, A Romano, JG Thayer, D Urner, B Valant-Spaight, G Viehhauser, A Warburton, P Avery, C Prescott, AI Rubiera, H Stoeck, J Yelton, G Brandenburg, A Ershov, DYJ Kim, R Wilson, T Bergfeld, BI Eisenstein, J Ernst, GE Gladding, GD Gollin, RM Hans, E Johnson, I Karliner, MA Marsh, C Plager, C Sedlack, M Selen, JJ Thaler, J Williams, KW Edwards, R Janicek, PM Patel, AJ Sadoff, R Ammar, A Bean, D Besson, X Zhao, S Anderson, VV Frolov, Y Kubota, SJ Lee, JJ O'Neill, R Poling, T Riehle, A Smith, CJ Stepaniak, J Urheim, S Ahmed, MS Alam, SB Athar, L Jian, L Ling, M Saleem, S Timm, F Wappler, A Anastassov, E Eckhart, KK Gan, C Gwon, T Hart, K Honscheid, D Hufnagel, H Kagan, R Kass, TK Pedlar, H Schwarthoff

Abstract:

We report on a search for the decay B+→D*+Ks0 and its charge conjugate with the CLEO detector at the Cornell Electron Storage Ring (CESR). No candidates are found in 9.10 fb-1 of data. The background is estimated to be 0.29±0.05 leading to an upper limit B(B+→D*+K0) = 9.5×10-5 (90% confidence level). ©2001 The American Physical Society.
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Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP

European Physical Journal C 19:1 (2001) 15-28

Authors:

P Abreu, W Adam, T Adye, P Adzic, I Ajinenko, Z Albrecht, T Alderweireld, GD Alekseev, R Alemany, T Allmendinger, PP Allport, S Almehed, U Amaldi, N Amapane, S Amato, EG Anassontzis, P Andersson, A Andreazza, S Andringa, P Antilogus, WD Apel, Y Arnoud, B Åsman, JE Augustin, A Augustinus, P Baillon, P Bambade, F Barao, G Barbiellini, R Barbier, DY Bardin, G Barker, A Baroncelli, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, P Beilliere, Y Belokopytov, NC Benekos, AC Benvenuti, C Berat, M Berggren, D Bertrand, M Besancon, M Bigi, MS Bilenky, MA Bizouard, D Bloch, HM Blom, M Bonesini, M Boonekamp, PSL Booth, AW Borgland, G Borisov, C Bosio, O Botner, E Boudinov, B Bouquet, C Bourdarios, TJV Bowcock, I Boyko, I Bozovic, M Bozzo, M Bracko, P Branchini, RA Brenner, P Bruckman, JM Brunet, L Bugge, T Buran, B Buschbeck, P Buschmann, S Cabrera, M Caccia, M Calvi, T Camporesi, V Canale, F Carena, L Carroll, C Caso, MV Castillo Gimenez, A Cattai, FR Cavallo, V Chabaud, P Charpentier, P Checchia, GA Chelkov, R Chierici, P Chliapnikov, P Chochula, V Chorowicz, J Chudoba, K Cieslik, P Collins, R Contri, E Cortina, G Cosme, F Cossutti

Abstract:

Muon pair production in the process e+e- → e+e- μ+μ- is studied using the data taken at LEP1 (√s ≃ mz) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb-1. The QED predictions have been tested over the whole Q2 range accessible at LEP1 (from several GeV2/c4 to several hundred GeV2/c4) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function Fγ2. Azimuthal correlations are used to obtain information on additional structure functions, FγA and FγB, which originate from interference terms of the scattering amplitudes. The measured ratios FγA/Fγ2 and FγB/Fγ2 are significantly different from zero and consistent with QED predictions.
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A measurement of the Tau topological branching ratios

EUROPEAN PHYSICAL JOURNAL C 20:4 (2001) 617-637

Authors:

P Abreu, W Adam, T Adye, P Adzic, Z Albrecht, T Alderweireld, GD Alekseev, R Alemany, T Allmendinger, PP Allport, S Almehed, U Amaldi, N Amapane, S Amato, E Anashkin, EG Anassontzis, P Andersson, A Andreazza, S Andringa, N Anjos, P Antilogus, WD Apel, Y Arnoud, B Åsman, JE Augustin, A Augustinus, P Baillon, A Ballestrero, P Bambade, F Barao, G Barbiellini, R Barbier, DY Bardin, G Barker, A Baroncelli, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, T Bellunato, Y Belokopytov, K Belous, NC Benekos, AC Benvenuti, C Berat, M Berggren, L Berntzon, D Bertrand, M Besancon, N Besson, MS Bilenky, D Bloch, HM Blom, J Bol, M Bonesini, M Boonekamp, PSL Booth, G Borisov, C Bosio, O Botner, E Boudinov, B Bouquet, TJV Bowcock, I Boyko, I Bozovic, M Bozzo, M Bracko, P Branchini, RA Brenner, E Brodet, P Bruckman, JM Brunet, L Bugge, P Buschmann, M Caccia, M Calvi, T Camporesi, V Canale, F Carena, L Carroll, C Caso, A Cattai, FR Cavallo, M Chapkin, P Charpentier, P Checehia, GA Chelkov, R Chierici, P Chliapnikov, P Chochula, V Chorowicz, J Chudoba, SH Chung, K Cieslik, P Collins, R Contri, G Cosme, F Cossutti, M Costa, HB Crawley, D Crennell, J Croix, JC Maestro, S Czellar, J D'Hondt, J Dalmau, M Davenport, W Da Silva, G Della Ricca, P Delpierre, N Demaria, A De Angelis, W De Boer, C De Clercq, B De Lotto, A De Min, L De Paula, H Dijkstra, L Di Ciaccio, K Doroba, M Dracos, J Drees, M Dris, G Eigen, T Ekelof, M Ellert, M Elsing, JP Engel, ME Santo, G Fanourakis, D Fassouliotis, T Feindt, J Fernandez, A Ferrer, E Ferrer-Ribas, F Ferro, A Firestone, U Flagmeyer, H Foeth, E Fokitis, F Fontanelli, B Franek, AG Frodesen, R Fruhwirth, F Fulda-Quenzer, J Fuster, D Gamba, S Gamblin, M Gandelman, C Garcia, C Gaspar, M Gaspar, U Gasparini, P Gavillet, EN Gazis, D Gele, T Geralis, N Ghodbane, F Glege, R Gokieli, B Golob, G Gomez-Ceballos, P Goncalves, IG Caballero, G Gopal, L Gorn, Y Gouz, V Gracco, J Grahl, E Graziani, G Grosdidier, K Grzelak, J Guy, C Haag, F Hahn, S Hahn, S Haider, Z Hajduk, A Hallgren, K Hamacher, K Hamilton, J Hansen, FJ Harris, S Haug, F Hauler, V Hedberg, S Heising, P Herquet, H Herr, O Hertz, E Higon, SO Holmgren, PJ Holt, S Hoorelbeke, M Houlden, J Hrubec, GJ Hughes, K Hultqvist, JN Jackson, R Jacobsson, C Jarlskog, G Jarlskog, P Jarry, B Jean-Marie, D Jeans, EK Johansson, P Jonsson, C Joram, P Juillot, L Jungermann, F Kapusta, K Karafasoulis, S Katsanevas, EC Katsoufis, R Keranen, G Kernel, BP Kersevan, BA Khomenko, NN Khovanski, A Kiiskinen, B King, A Kinvig, NJ Kjaer, O Klapp, P Kluit, P Kokkinias, V Kostioukhine, C Kourkoumelis, O Kouznetsov, M Krammer, E Kriznic, Z Krumstein, P Kubinec, W Kucewicz, M Kucharczyk, J Kurowska, JW Lamsa, JP Laugier, G Leder, F Ledroit, L Leinonen, A Leisos, R Leitner, J Lemonne, G Lenzen, V Lepeltier, M Lethuillier, J Libby, W Liebig, D Liko, A Lipniacka, I Lippi, JG Loken, JH Lopes, JM Lopez, R Lopez-Fernandez, D Loukas, P Lutz, L Lyons, J MacNaughton, JR Mahon, A Maio, A Malek, S Maltezos, V Malychev, F Mandl, J Marco, R Marco, B Marechal, M Margoni, JC Marin, C Mariotti, A Markou, C Martinez-Rivero, SMI Garcia, J Masik, N Mastroyiannopoulos, F Matorras, C Matteuzzi, G Matthiae, F Mazzucato, M Mazzucato, M Mc Cubbin, R Mc Kay, R Mc Nulty, E Merle, C Meroni, WT Meyer, A Miagkov, E Migliore, L Mirabito, WA Mitaroff, U Mjoernmark, T Moa, M Moch, K Moenig, MR Monge, J Montenegro, D Moraes, P Morettini, G Morton, U Mueller, K Muenich, M Mulders, LM Mundim, WJ Murray, G Myatt, T Myklebust, M Nassiakou, FL Navarria, K Nawrocki, P Negri, S Nemecek, N Neufeld, R Nicolaidou, P Niezurawski, T Nikolenko, V Nomokonov, A Nygren, A Oblakowska-Mucha, V Obraztsov, AG Olshevski, A Onofre, R Orava, K Osterberg, A Ouraou, A Oyanguren, M Paganoni, S Paiano, R Pain, R Paiva, J Palacios, H Palka, TD Papadopoulou, L Pape, C Parkes, F Parodi, U Parzefall, A Passeri, O Passon, L Peralta, V Perepelitsa, M Pernicka, A Perrotta, C Petridou, A Petrolini, HT Phillips, F Pierre, M Pimenta, E Piotto, T Podobnik, V Poireau, ME Pol, G Polok, P Poropat, V Pozdniakov, P Privitera, N Pukhaeva, A Pullia, D Radojicic, S Ragazzi, H Rahmani, PN Ratoff, AL Read, P Rebecchi, NG Redaelli, M Regler, J Rehn, D Reid, R Reinhardt, PB Renton, LK Resvanis, F Richard, J Ridky, G Rinaudo, I Ripp-Baudot, A Romero, P Ronchese, EI Rosenberg, P Rosinsky, P Roudeau, T Rovelli, V Ruhlmann-Kleider, A Ruiz, H Saarikko, Y Sacquin, A Sadovsky, G Sajot, L Salmi, J Salt, D Sampsonidis, M Sannino, A Savoy-Navarro, C Schwanda, P Schwemling, B Schwering, U Schwickerath, F Scuri, P Seager, Y Sedykh, AM Segar, R Sekulin, G Sette, RC Shellard, M Siebel, L Simard, F Simonetto, AN Sisakian, G Smadja, N Smirnov, O Smirnova, GR Smith, A Sokolov, O Solovianov, A Sopczak, R Sosnowski, T Spassov, E Spiriti, S Squarcia, C Stanescu, M Stanitzki, A Stocchi, J Strauss, R Strub, D Stugu, M Szczekowski, M Szeptycka, T Szumlak, T Tabarelli, A Taffard, F Tegenfeldt, F Terranova, J Timmermans, N Tinti, LG Tkatchev, M Tobin, S Todorova, B Tome, L Tortora, P Tortosa, D Treille, G Tristram, M Trochimczuk, C Troncon, ML Turluer, IA Tyapkin, P Tyapkin, S Tzamarias, O Ullaland, V Uvarov, G Valenti, E Vallazza, CV Velde, P Van Dam, W Van den Boeck, WK Van Doninck, J Van Eldik, A Van Lysebetten, N van Remortel, I Van Vulpen, G Vegni, L Ventura, W Venus, F Verbeure, P Verdier, M Verlato, LS Vertogradov, V Verzi, D Vilanova, L Vitale, E Vlasov, AS Vodopyanov, G Voulgaris, V Vrba, H Wahlen, AJ Washbrook, C Weiser, D Wicke, JH Wickens, GR Wilkinson, M Winter, G Wolf, J Yi, O Yushchenko, A Zalewska, P Zalewski, D Zavrtanik, E Zevgolatakos, NI Zimin, A Zintchenko, P Zoller, G Zumerle, M Zupan
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