Search for Exclusive Z-Boson Production and Observation of High-Mass pp̅ →pγγp̅ →pl⁺l^-p̅ Events in pp̅ Collisions at √s=1.96  TeV

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T. Aaltonen²⁴, J. Adelman¹⁴, T. Akimoto⁵⁶, M. G. Albrow¹⁸, B. Álvarez González^12,m, S. Amerio^44b,44a, D. Amidei³⁵, A. Anastassov³⁹, A. Annovi²⁰, J. Antos¹⁵, G. Apollinari¹⁸, A. Apresyan⁴⁹, T. Arisawa⁵⁸, A. Artikov¹⁶, W. Ashmanskas¹⁸, A. Attal⁴, A. Aurisano⁵⁴, F. Azfar⁴³, W. Badgett¹⁸, A. Barbaro-Galtieri²⁹, V. E. Barnes⁴⁹, B. A. Barnett²⁶, P. Barria^47c,47a, V. Bartsch³¹, G. Bauer³³, P.-H. Beauchemin³⁴, F. Bedeschi^47a, D. Beecher³¹, S. Behari²⁶, G. Bellettini^47b,47a, J. Bellinger⁶⁰, D. Benjamin¹⁷, A. Beretvas¹⁸, J. Beringer²⁹, A. Bhatti⁵¹, M. Binkley¹⁸, D. Bisello^44b,44a, I. Bizjak^31,r, R. E. Blair², C. Blocker⁷, B. Blumenfeld²⁶, A. Bocci¹⁷, A. Bodek⁵⁰, V. Boisvert⁵⁰, G. Bolla⁴⁹, D. Bortoletto⁴⁹, J. Boudreau⁴⁸, A. Boveia¹¹, B. Brau^11,†, A. Bridgeman²⁵, L. Brigliadori^6b,6a, C. Bromberg³⁶, E. Brubaker¹⁴, J. Budagov¹⁶, H. S. Budd⁵⁰, S. Budd²⁵, S. Burke¹⁸, K. Burkett¹⁸, G. Busetto^44b,44a, P. Bussey²², A. Buzatu³⁴, K. L. Byrum², S. Cabrera^17,o, C. Calancha³², M. Campanelli³⁶, M. Campbell³⁵, F. Canelli^14,18, A. Canepa⁴⁶, B. Carls²⁵, D. Carlsmith⁶⁰, R. Carosi^47a, S. Carrillo^19,h, S. Carron³⁴, B. Casal¹², M. Casarsa¹⁸, A. Castro^6b,6a, P. Catastini^47c,47a, D. Cauz^55b,55a, V. Cavaliere^47c,47a, M. Cavalli-Sforza⁴, A. Cerri²⁹, L. Cerrito^31,i, S. H. Chang²⁸, Y. C. Chen¹, M. Chertok⁸, G. Chiarelli^47a, G. Chlachidze¹⁸, F. Chlebana¹⁸, K. Cho²⁸, D. Chokheli¹⁶, J. P. Chou²³, G. Choudalakis³³, S. H. Chuang⁵³, K. Chung¹³, W. H. Chung⁶⁰, Y. S. Chung⁵⁰, T. Chwalek²⁷, C. I. Ciobanu⁴⁵, M. A. Ciocci^47c,47a, A. Clark²¹, D. Clark⁷, G. Compostella⁶¹, M. E. Convery¹⁸, J. Conway⁸, M. Cordelli²⁰, G. Cortiana^44b,44a, C. A. Cox⁸, D. J. Cox⁸, F. Crescioli^47b,47a, C. Cuenca Almenar^8,o, J. Cuevas^12,m, R. Culbertson¹⁸, J. C. Cully³⁵, D. Dagenhart¹⁸, M. Datta¹⁸, T. Davies²², P. de Barbaro⁵⁰, S. De Cecco^52a, A. Deisher²⁹, G. De Lorenzo⁴, M. Dell’Orso^47b,47a, C. Deluca⁴, L. Demortier⁵¹, J. Deng¹⁷, M. Deninno^6a, P. F. Derwent¹⁸, A. Di Canto^47b,47a, G. P. di Giovanni⁴⁵, C. Dionisi^52b,52a, B. Di Ruzza^55b,55a, J. R. Dittmann⁵, M. D’Onofrio⁴, S. Donati^47b,47a, P. Dong⁹, J. Donini⁶¹, T. Dorigo⁶¹, S. Dube⁵³, J. Efron⁴⁰, A. Elagin⁵⁴, R. Erbacher⁸, D. Errede²⁵, S. Errede²⁵, R. Eusebi¹⁸, H. C. Fang²⁹, S. Farrington⁴³, W. T. Fedorko¹⁴, R. G. Feild⁶¹, M. Feindt²⁷, J. P. Fernandez³², C. Ferrazza^47d,47a, R. Field¹⁹, G. Flanagan⁴⁹, R. Forrest⁸, M. J. Frank⁵, M. Franklin²³, J. C. Freeman¹⁸, I. Furic¹⁹, M. Gallinaro^52a, J. Galyardt¹³, F. Garberson¹¹, J. E. Garcia²¹, A. F. Garfinkel⁴⁹, P. Garosi^47c,47a, K. Genser¹⁸, H. Gerberich²⁵, D. Gerdes³⁵, A. Gessler²⁷, S. Giagu^52b,52a, V. Giakoumopoulou³, P. Giannetti^47a, K. Gibson⁴⁸, J. L. Gimmell⁵⁰, C. M. Ginsburg¹⁸, N. Giokaris³, M. Giordani^55b,55a, P. Giromini²⁰, M. Giunta^47a, G. Giurgiu²⁶, V. Glagolev¹⁶, D. Glenzinski¹⁸, M. Gold³⁸, N. Goldschmidt¹⁹, A. Golossanov¹⁸, G. Gomez¹², G. Gomez-Ceballos³³, M. Goncharov³³, O. González³², I. Gorelov³⁸, A. T. Goshaw¹⁷, K. Goulianos⁵¹, A. Gresele^44b,44a, S. Grinstein²³, C. Grosso-Pilcher¹⁴, R. C. Group¹⁸, U. Grundler²⁵, J. Guimaraes da Costa²³, Z. Gunay-Unalan³⁶, C. Haber²⁹, K. Hahn³³, S. R. Hahn¹⁸, E. Halkiadakis⁵³, B.-Y. Han⁵⁰, J. Y. Han⁵⁰, F. Happacher²⁰, K. Hara⁵⁶, D. Hare⁵³, M. Hare⁵⁷, S. Harper⁴³, R. F. Harr⁵⁹, R. M. Harris¹⁸, M. Hartz⁴⁸, K. Hatakeyama⁵¹, C. Hays⁴³, M. Heck²⁷, A. Heijboer⁴⁶, J. Heinrich⁴⁶, C. Henderson³³, M. Herndon⁶⁰, J. Heuser²⁷, S. Hewamanage⁵, D. Hidas¹⁷, C. S. Hill^11,§, D. Hirschbuehl²⁷, A. Hocker¹⁸, S. Hou¹, M. Houlden³⁰, S.-C. Hsu²⁹, B. T. Huffman⁴³, R. E. Hughes⁴⁰, U. Husemann⁶¹, M. Hussein³⁶, J. Huston³⁶, J. Incandela¹¹, G. Introzzi^47a, M. Iori^52b,52a, A. Ivanov⁸, E. James¹⁸, D. Jang¹³, B. Jayatilaka¹⁷, E. J. Jeon²⁸, M. K. Jha^6a, S. Jindariani¹⁸, W. Johnson⁸, M. Jones⁴⁹, K. K. Joo²⁸, S. Y. Jun¹³, J. E. Jung²⁸, T. R. Junk¹⁸, T. Kamon⁵⁴, D. Kar¹⁹, P. E. Karchin⁵⁹, Y. Kato^42,f, R. Kephart¹⁸, W. Ketchum¹⁴, J. Keung⁴⁶, V. Khotilovich⁵⁴, B. Kilminster¹⁸, D. H. Kim²⁸, H. S. Kim²⁸, H. W. Kim²⁸, J. E. Kim²⁸, M. J. Kim²⁰, S. B. Kim²⁸, S. H. Kim⁵⁶, Y. K. Kim¹⁴, N. Kimura⁵⁶, L. Kirsch⁷, S. Klimenko¹⁹, B. Knuteson³³, B. R. Ko¹⁷, K. Kondo⁵⁸, D. J. Kong²⁸, J. Konigsberg¹⁹, A. Korytov¹⁹, A. V. Kotwal¹⁷, M. Kreps²⁷, J. Kroll⁴⁶, D. Krop¹⁴, N. Krumnack⁵, M. Kruse¹⁷, V. Krutelyov¹¹, T. Kubo⁵⁶, T. Kuhr²⁷, N. P. Kulkarni⁵⁹, M. Kurata⁵⁶, S. Kwang¹⁴, A. T. Laasanen⁴⁹, S. Lami^47a, S. Lammel¹⁸, M. Lancaster³¹, R. L. Lander⁸, K. Lannon^40,l, A. Lath⁵³, G. Latino^47c,47a, I. Lazzizzera^44b,44a, T. LeCompte², E. Lee⁵⁴, H. S. Lee¹⁴, S. W. Lee^54,n, S. Leone^47a, J. D. Lewis¹⁸, C.-S. Lin²⁹, J. Linacre⁴³, M. Lindgren¹⁸, E. Lipeles⁴⁶, A. Lister⁸, D. O. Litvintsev¹⁸, C. Liu⁴⁸, T. Liu¹⁸, N. S. Lockyer⁴⁶, A. Loginov⁶¹, M. Loreti^44b,44a, L. Lovas¹⁵, D. Lucchesi^44b,44a, C. Luci^52b,52a, J. Lueck²⁷, P. Lujan²⁹, P. Lukens¹⁸, G. Lungu⁵¹, L. Lyons⁴³, J. Lys²⁹, R. Lysak¹⁵, D. MacQueen³⁴, R. Madrak¹⁸, K. Maeshima¹⁸, K. Makhoul³³, T. Maki²⁴, P. Maksimovic²⁶, S. Malde⁴³, S. Malik³¹, G. Manca^30,††, A. Manousakis-Katsikakis³, F. Margaroli⁴⁹, C. Marino²⁷, C. P. Marino²⁵, A. Martin⁶¹, V. Martin^22,e, M. Martínez⁴, R. Martínez-Ballarín³², T. Maruyama⁵⁶, P. Mastrandrea^52a, T. Masubuchi⁵⁶, M. Mathis²⁶, M. E. Mattson⁵⁹, P. Mazzanti^6a, K. S. McFarland⁵⁰, P. McIntyre⁵⁴, R. McNulty^30,d, A. Mehta³⁰, P. Mehtala²⁴, A. Menzione^47a, P. Merkel⁴⁹, C. Mesropian⁵¹, T. Miao¹⁸, N. Miladinovic⁷, R. Miller³⁶, C. Mills²³, M. Milnik²⁷, A. Mitra¹, G. Mitselmakher¹⁹, H. Miyake⁵⁶, N. Moggi^6a, C. S. Moon²⁸, R. Moore¹⁸, M. J. Morello^47a, J. Morlock²⁷, P. Movilla Fernandez¹⁸, J. Mülmenstädt²⁹, A. Mukherjee¹⁸, Th. Muller²⁷, R. Mumford²⁶, P. Murat¹⁸, M. Mussini^6b,6a, J. Nachtman¹⁸, Y. Nagai⁵⁶, A. Nagano⁵⁶, J. Naganoma⁵⁶, K. Nakamura⁵⁶, I. Nakano⁴¹, A. Napier⁵⁷, V. Necula¹⁷, J. Nett⁶⁰, C. Neu^46,p, M. S. Neubauer²⁵, S. Neubauer²⁷, J. Nielsen^29,a, L. Nodulman², M. Norman¹⁰, O. Norniella²⁵, E. Nurse³¹, L. Oakes⁴³, S. H. Oh¹⁷, Y. D. Oh²⁸, I. Oksuzian¹⁹, T. Okusawa⁴², R. Orava²⁴, K. Osterberg²⁴, S. Pagan Griso^44b,44a, E. Palencia¹⁸, V. Papadimitriou¹⁸, A. Papaikonomou²⁷, A. A. Paramonov¹⁴, B. Parks⁴⁰, S. Pashapour³⁴, J. Patrick¹⁸, G. Pauletta^55b,55a, M. Paulini¹³, C. Paus³³, T. Peiffer²⁷, D. E. Pellett⁸, A. Penzo^55a, T. J. Phillips¹⁷, G. Piacentino^47a, E. Pianori⁴⁶, L. Pinera¹⁹, J. Pinfold³⁴, K. Pitts²⁵, C. Plager⁹, L. Pondrom⁶⁰, O. Poukhov^16,*, N. Pounder⁴³, F. Prakoshyn¹⁶, A. Pronko¹⁸, J. Proudfoot², F. Ptohos^18,c, E. Pueschel¹³, G. Punzi^47b,47a, J. Pursley⁶⁰, J. Rademacker^43,§, A. Rahaman⁴⁸, V. Ramakrishnan⁶⁰, N. Ranjan⁴⁹, I. Redondo³², P. Renton⁴³, M. Renz²⁷, M. Rescigno^52a, S. Richter²⁷, F. Rimondi^6b,6a, L. Ristori^47a, A. Robson²², T. Rodrigo¹², T. Rodriguez⁴⁶, E. Rogers²⁵, S. Rolli⁵⁷, R. Roser¹⁸, M. Rossi^55a, R. Rossin¹¹, P. Roy³⁴, A. Ruiz¹², J. Russ¹³, V. Rusu¹⁸, B. Rutherford¹⁸, H. Saarikko²⁴, A. Safonov⁵⁴, W. K. Sakumoto⁵⁰, O. Saltó⁴, L. Santi^55b,55a, S. Sarkar^52b,52a, L. Sartori^47a, K. Sato¹⁸, A. Savoy-Navarro⁴⁵, P. Schlabach¹⁸, A. Schmidt²⁷, E. E. Schmidt¹⁸, M. A. Schmidt¹⁴, M. P. Schmidt⁶¹, M. Schmitt³⁹, T. Schwarz⁸, L. Scodellaro¹², A. Scribano^47c,47a, F. Scuri^47a, A. Sedov⁴⁹, S. Seidel³⁸, Y. Seiya⁴², A. Semenov¹⁶, L. Sexton-Kennedy¹⁸, F. Sforza^47b,47a, A. Sfyrla²⁵, S. Z. Shalhout⁵⁹, T. Shears³⁰, P. F. Shepard⁴⁸, M. Shimojima^56,k, S. Shiraishi¹⁴, M. Shochet¹⁴, Y. Shon⁶⁰, I. Shreyber³⁷, P. Sinervo³⁴, A. Sisakyan¹⁶, A. J. Slaughter¹⁸, J. Slaunwhite⁴⁰, K. Sliwa⁵⁷, J. R. Smith⁸, F. D. Snider¹⁸, R. Snihur³⁴, A. Soha⁸, S. Somalwar⁵³, V. Sorin³⁶, J. Spalding¹⁸, T. Spreitzer³⁴, P. Squillacioti^47c,47a, M. Stanitzki⁶¹, R. St. Denis²², B. Stelzer³⁴, O. Stelzer-Chilton³⁴, D. Stentz³⁹, J. Strologas³⁸, G. L. Strycker³⁵, D. Stuart¹¹, J. S. Suh²⁸, A. Sukhanov¹⁹, I. Suslov¹⁶, T. Suzuki⁵⁶, A. Taffard^25,‡‡, R. Takashima⁴¹, Y. Takeuchi⁵⁶, R. Tanaka⁴¹, M. Tecchio³⁵, P. K. Teng¹, K. Terashi⁵¹, J. Thom^18,b, A. S. Thompson²², G. A. Thompson²⁵, E. Thomson⁴⁶, P. Tipton⁶¹, P. Ttito-Guzmán³², S. Tkaczyk¹⁸, D. Toback⁵⁴, S. Tokar¹⁵, K. Tollefson³⁶, T. Tomura⁵⁶, D. Tonelli¹⁸, S. Torre²⁰, D. Torretta¹⁸, P. Totaro^55b,55a, S. Tourneur⁴⁵, M. Trovato^47d,47a, S.-Y. Tsai¹, Y. Tu⁴⁶, N. Turini^47c,47a, F. Ukegawa⁵⁶, S. Vallecorsa²¹, N. van Remortel^24,‡, A. Varganov³⁵, E. Vataga^47d,47a, F. Vázquez^19,h, G. Velev¹⁸, C. Vellidis³, M. Vidal³², R. Vidal¹⁸, I. Vila¹², R. Vilar¹², T. Vine³¹, M. Vogel³⁸, I. Volobouev^29,n, G. Volpi^47b,47a, P. Wagner⁴⁶, R. G. Wagner², R. L. Wagner¹⁸, W. Wagner^27,q, J. Wagner-Kuhr²⁷, T. Wakisaka⁴², R. Wallny⁹, S. M. Wang¹, A. Warburton³⁴, D. Waters³¹, M. Weinberger⁵⁴, J. Weinelt²⁷, W. C. Wester, III¹⁸, B. Whitehouse⁵⁷, D. Whiteson^46,‡‡, A. B. Wicklund², E. Wicklund¹⁸, S. Wilbur¹⁴, G. Williams³⁴, H. H. Williams⁴⁶, P. Wilson¹⁸, B. L. Winer⁴⁰, P. Wittich^18,b, S. Wolbers¹⁸, C. Wolfe¹⁴, T. Wright³⁵, X. Wu²¹, F. Würthwein¹⁰, S. Xie³³, A. Yagil¹⁰, K. Yamamoto⁴², J. Yamaoka¹⁷, U. K. Yang^14,j, Y. C. Yang²⁸, W. M. Yao²⁹, G. P. Yeh¹⁸, J. Yoh¹⁸, K. Yorita⁵⁸, T. Yoshida^42,g, G. B. Yu⁵⁰, I. Yu²⁸, S. S. Yu¹⁸, J. C. Yun¹⁸, L. Zanello^52b,52a, A. Zanetti^55a, L. Zhang³⁴, X. Zhang²⁵, Y. Zheng^9,**, and S. Zucchelli^6b,6a (CDF Collaboration)
¹Institute of Physics, Academia Sinica, Taipei, Taiwan 11529, Republic of China
²Argonne National Laboratory, Argonne, Illinois 60439, USA
³University of Athens, 157 71 Athens, Greece
⁴Institut de Fisica d’Altes Energies, Universitat Autonoma de Barcelona, E-08193, Bellaterra (Barcelona), Spain
⁵Baylor University, Waco, Texas 76798, USA
^6aIstituto Nazionale di Fisica Nucleare Bologna, I-40127 Bologna, Italy
^6bIstituto Nazionale di Fisica Nucleare Bologna, I-40127 Bologna, Italy
⁷Brandeis University, Waltham, Massachusetts 02254, USA
⁸University of California, Davis, Davis, California 95616, USA
⁹University of California, Los Angeles, Los Angeles, California 90024, USA
¹⁰University of California, San Diego, La Jolla, California 92093, USA
¹¹University of California, Santa Barbara, Santa Barbara, California 93106, USA
¹²Instituto de Fisica de Cantabria, CSIC-University of Cantabria, 39005 Santander, Spain
¹³Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
¹⁴Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
¹⁵Comenius University, 842 48 Bratislava, Slovakia; Institute of Experimental Physics, 040 01 Kosice, Slovakia
¹⁶Joint Institute for Nuclear Research, RU-141980 Dubna, Russia
¹⁷Duke University, Durham, North Carolina 27708, USA
¹⁸Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
¹⁹University of Florida, Gainesville, Florida 32611, USA
²⁰Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare, I-00044 Frascati, Italy
²¹University of Geneva, CH-1211 Geneva 4, Switzerland
²²Glasgow University, Glasgow G12 8QQ, United Kingdom
²³Harvard University, Cambridge, Massachusetts 02138, USA
²⁴Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki, Finland
²⁵University of Illinois, Urbana, Illinois 61801, USA
²⁶The Johns Hopkins University, Baltimore, Maryland 21218, USA
²⁷Institut für Experimentelle Kernphysik, Universität Karlsruhe, 76128 Karlsruhe, Germany
²⁸Center for High Energy Physics: Kyungpook National University, Daegu 702-701, Korea; Seoul National University, Seoul 151-742, Korea; Sungkyunkwan University, Suwon 440-746, Korea; Korea Institute of Science and Technology Information, Daejeon, 305-806, Korea; Chonnam National University, Gwangju, 500-757, Korea
²⁹Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
³⁰University of Liverpool, Liverpool L69 7ZE, United Kingdom
³¹University College London, London WC1E 6BT, United Kingdom
³²Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, E-28040 Madrid, Spain
³³Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
³⁴Institute of Particle Physics: University of Alberta, Edmonton, Canada, T6G 2G7; McGill University, Montréal, Québec, Canada H3A 2T8; Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6; University of Toronto, Toronto, Ontario, Canada M5S 1A7; and TRIUMF, Vancouver, British Columbia, Canada V6T 2A3
³⁵University of Michigan, Ann Arbor, Michigan 48109, USA
³⁶Michigan State University, East Lansing, Michigan 48824, USA
³⁷Institution for Theoretical and Experimental Physics, ITEP, Moscow 117259, Russia
³⁸University of New Mexico, Albuquerque, New Mexico 87131, USA
³⁹Northwestern University, Evanston, Illinois 60208, USA
⁴⁰The Ohio State University, Columbus, Ohio 43210, USA
⁴¹Okayama University, Okayama 700-8530, Japan
⁴²Osaka City University, Osaka 588, Japan
⁴³University of Oxford, Oxford OX1 3RH, United Kingdom
^44aIstituto Nazionale di Fisica Nucleare, Sezione di Padova-Trento, I-35131 Padova, Italy
^44bUniversity of Padova, I-35131 Padova, Italy
⁴⁵LPNHE, Universite Pierre et Marie Curie/IN2P3-CNRS, UMR7585, Paris, F-75252 France
⁴⁶University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
^47aIstituto Nazionale di Fisica Nucleare Pisa, I-56127 Pisa, Italy
^47bUniversity of Pisa, I-56127 Pisa, Italy
^47cUniversity of Siena, I-56127 Pisa, Italy
^47dScuola Normale Superiore, I-56127 Pisa, Italy
⁴⁸University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
⁴⁹Purdue University, West Lafayette, Indiana 47907, USA
⁵⁰University of Rochester, Rochester, New York 14627, USA
⁵¹The Rockefeller University, New York, New York 10021, USA
^52aIstituto Nazionale di Fisica Nucleare, Sezione di Roma 1, I-00185 Roma, Italy
^52bSapienza Università di Roma, I-00185 Roma, Italy
⁵³Rutgers University, Piscataway, New Jersey 08855, USA
⁵⁴Texas A&M University, College Station, Texas 77843, USA
^55aIstituto Nazionale di Fisica Nucleare Trieste/Udine, I-34100 Trieste, Italy
^55bUniversity of Trieste/Udine, I-33100 Udine, Italy
⁵⁶University of Tsukuba, Tsukuba, Ibaraki 305, Japan
⁵⁷Tufts University, Medford, Massachusetts 02155, USA
⁵⁸Waseda University, Tokyo 169, Japan
⁵⁹Wayne State University, Detroit, Michigan 48201
⁶⁰University of Wisconsin, Madison, Wisconsin 53706, USA
⁶¹Yale University, New Haven, Connecticut 06520, USA

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