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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 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 Elsevier 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
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Consistent measurements of αs from precise oriented event shape distributions (vol 14, pg 557, 2000)

EUROPEAN PHYSICAL JOURNAL C 19:4 (2001) 761-763

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, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, P Beilliere, Y Belokopytov, NC Benekos, AC Benvenuti, C Berat, M Berggren, D Bertini, 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, P Branchini, T Brenke, RA Brenner, P Bruckman, JM Brunet, L Bugge, T Buran, T Burgsmueller, B Buschbeck, P Buschmann, S Cabrera, M Calvi, T Camporesi, V Canale, F Carena, L Carroll, C Caso, MVC Gimenez, A Cattai, FR Cavallo, V Chabaud, P Charpentier, L Chaussard, 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, JH Cowell, HB Crawley, D Crennell, S Crepe, G Crosetti, JC Maestro, S Czellar, M Davenport, W Da Silva, A Deghorain, 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 De Ciaccio, J Dolbeau, K Doroba, M Dracos, J Drees, M Dris, A Duperrin, JD Durand, G Eigen, T Ekelof, G Ekspong, M Ellert, M Elsing, JP Engel, B Erzen, ME Santo, G Fanourakis, D Fassouliotis, J Fayot, M Feindt, A Fenyuk, A Ferrer, E Ferrer-Ribas, F Ferro, S Fichet, A Firestone, U Flagmeyer, H Foeth, E Fokitis, F Fontanelli, B Franck, AG Frodesen, R Fruhwirth, F Fulda-Quenzer, J Fuster, A Galloni, D Gamba, S Gamblin, M Gandelman, C Garcia, C Gaspar, M Gaspar, U Gasparini, P Gavillet, EN Gazis, D Gelel, N Ghodbane, I Gil, 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, C Green, HJ Grimm, P Gris, G Grosdidier, K Grzelak, M Gunther, J Guy, F Hahn, S Hahn, S Haider, A Hallgren, K Hamacher, J Hansen, FJ Harris, V Hedberg, S Heising, JJ Hernandez, P Herquet, H Herr, TL Hessing, JM Heuser, E Higon, SO Holmgren, PJ Holt, S Hoorelbeke, M Houlden, J Hrubec, K Huet, GJ Hughes, K Hultqvist, JN Jackson, R Jacobsson, P Jalocha, R Janik, C Jarlskog, G Jarlskog, P Jarry, B Jean-Marie, EK Johansson, P Jonsson, C Joram, P Juillot, F Kapusta, K Karafasoulis, S Katsanevas, EC Katsoufis, R Keranen, BP Kersevan, BA Khomenko, NN Khovanski, A Kiiskinen, B King, A Kinvig, NJ Kjaer, O Klapp, H Klein, P Kluit, P Kokkinias, M Koratzinos, C Kourkoumelis, V Kostioukhine, O Kouznetsov, M Krammer, E Kriznic, Z Krumstein, P Kubinec, J Kurowska, K Kurvinen, JW Lamsa, DW Lane, P Langefeld, V Lapin, JP Laugier, R Lauhakangas, G Leder, F Ledroit, V Lefeburc, L Leinonen, A Leisos, R Leitner, J Lemonne, G Lenzen, V Lepeltier, T Lesiak, M Lethuiller, J Libby, D Liko, A Lipniacka, I Lippi, B Loerstad, JG Loken, JH Lopes, JM Lopez, R Lopez-Fernandez, D Loukas, P Lutz, L Lyons, J MacNaughton, JR Mahon, A Maio, A Malek, TGH Malmgren, S Maltezos, V Malychev, F Mandl, J Marco, R Marco, B Marechal, M Margoni, JC Marin, C Mariotti, A Markou, C Martinez-Rivero, F Martiniz-Vidal, SMI Garcia, J Masik, N Mastroyiannopoulos, F Matorras, C Matteuzzi, G Matthiae, F Mazzucato, M Mc Cubbin, R Mc Kay, R Mc Nulty, G Mc Pherson, C Meroni, WT Meyer, A Miagkov, E Migliore, L Mirabito, WA Mitaroff, U Mjoernmark, T Moa, M Moch, R Moeller, K Moenig, MR Monge, X Moreau, P Morettini, G Morton, U Mueller, K Muenich, M Mulders, C Mulet-Harquis, R Muresan, WJ Murray, B Muryn, G Myatt, T Myklebust, F Naraghi, M Nassiakou, FL Navarria, S Navas, K Nawrocki, P Negri, S Nemecek, N Neufeld, R Nicolaidou, BS Nielson, P Niezurawski, M Nikolenko, V Nomokonov, A Normand, A Nygren, V Obraztsov, AG Olshevski, A Onofre, R Orava, C Orazi, K Osterberg, A Ouraou, M Paganoni, S Paiano, R Pain, R Paiva, J Palacios, H Palka, TD Papadopoulou, K Papageorgiou, L Pape, C Parkes, F Parodi, C Parzefall, A Passeri, O Passon, M Pegoraro, L Peralta, M Pernicka, A Perrotta, C Petridou, A Petrolini, HT Phillips, F Pierre, M Pimenta, E Piotto, T Podobnik, 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, D Reid, R Reinhardt, PB Renton, LK Resvanis, F Richard, J Ridky, G Rinaudo, G Rodrigo, O Rohne, A Romero, P Ronchese, EI Rosenberg, P Rosinsky, P Roudeau, T Rovelli, C Royon, V Ruhlmann-Kleider, A Ruiz, H Saarikko, Y Sacquin, A Sadovsky, G Sajot, J Salt, D Sampsonidis, M Sannino, H Schneider, P Schwemling, B Schwering, U Schwickerath, MAE Schyns, F Scuri, P Seager, Y Sedykh, AM Segar, R Sekulin, RC Shellard, A Sheridan, M Siebel, L Simard, F Simonetto, AN Sisakian, G Smadja, N Smirnov, O Smirnova, GR Smith, A Sokolov, A Sopczak, R Sosnowski, T Spassov, E Spiriti, P Sponholz, S Squarcia, C Stanescu, S Stanic, K Stevenson, A Stocchi, J Strauss, R Strub, B Stugu, M Szczekowski, M Szeptycka, T Tabarelli, F Tegenfeldt, F Terranova, J Thomas, J Timmermans, N Tinti, LG Tkatchev, S Todorova, A Tomaradze, B Tome, A Tonazzo, L Tortora, G Transtromer, D Treille, G Tristram, M Trochimezuk, C Troncon, A Tsirou, ML Turluer, IA Tyapkin, S Tzamarias, O Ullaland, V Uvarov, G Valenti, E Vallazza, C Vander Velde, GW Van Apeldoorn, P Van Dam, WK Van Doninck, J Van Eldik, A Van Lysebetten, N Van Remortel, I Van Vulpen, N Vassilopoulos, G Vegni, L Ventura, W Venus, F Verbeure, M Verlato, LS Vertogradov, V Verzi, D Vilanova, L Vitale, E Vlasov, AS Vodopyanov, C Vollmer, G Voulgaris, V Vrba, H Wahlen, C Walck, C Weiser, D Wicke, JH Wickens, GR Wilkinson, M Winter, M Witek, G Wolf, J Yi, O Yushchenko, A Zalewska, P Zalewski, D Zavtranik, E Zevgolatakos, NI Zimin, GC Zucchelli, G Zumerle
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Development of an optical front-end readout system for the LHCb RICH detectors.

CERN REPORT 2001:5 (2001) 150-154

Authors:

N Smale, N Adinolfi, J Bibby, G Damerell, N Harnew, S Topp-Jorgenson, V Gibson, VGS Katvars, S Wotton, K Wyllie

Abstract:

The development of a front-end readout system for the LHCb Ring Imaging Cherenkov (RICH) detectors is in progress. The baseline choice for the RICH photon detector front-end electronics is a binary readout ASIC for an encapsulated silicon pixel detector. This paper describes a system to transmit the binary data with address ID and error codes, from a radiation harsh environment while keeping synchronisation. The total data read out for the fixed Level-0 readout period of 900ns is 32x36x440 non-zero-suppressed bits per Level-0 trigger, with a sustained Level-0 trigger rate of 1MHz. Multimode fibres driven by VCSEL devices are used to transmit data to the off-detector Level-1 electronics located in a non-radiation environment. The data are stored in 512Kbit deep QDR buffers.
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Enhanced radiation hardness and faster front ends for the beetle readout chip

CERN REPORT 2001:5 (2001) 57-61

Authors:

N van Bakel, J van den Brand, H Verkooijen, C Bauer, D Baumeister, N Hofmann, KT Knopfle, S Lochner, M Schmelling, E Sexauer, M Feuerstack-Raible, U Trunk, N Harnew, N Smale

Abstract:

This paper summarizes the recent progress in the development of the 128 channel pipelined readout chip Beetle, which is intended for the silicon vertex detector, the inner tracker, the pile-up veto trigger and the RICH detectors(1) of LHCb.Deficiencies found in the front end of the Beetle Version 1.0 and 1.1 chips resulted in the submissions of BeetleFE 1.1 and BeetleFE 1.2, while BeetleSR 1.0 implements test circuits to provide future Beetle chips with logic circuits hardened against single event upset (SEU).Section I. motivates the development of new front ends for the Beetle chip, and section II. summarizes their concepts and construction. Section III. reports preliminary results from the BeetleFE 1.1 and BeetleFE 1.2 chips, while section IV. describes the BeetleSR 1.0 chip. An outlook on future test and development of the Beetle chip is given in section V.
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