Observation of exclusive deeply virtual Compton scattering in polarized electron beam asymmetry measurements - art. no. 182002

Authors
Stepanyan, S Burkert, VD Elouadrhiri, L Adams, GS Anciant, E Anghinolfi, M Asavapibhop, B Audit, G Auger, T Avakian, H Ball, J Barrow, S Battaglieri, M Beard, K Bektasoglu, M Bertin, P Bianchi, N Biselli, A Boiarinov, S Bonner, BE Bouchigny, S Branford, D Brooks, WK Calarco, JR Carman, DS Carnahan, B Ciciani, L Cole, PL Coleman, A Cords, D Corvisiero, P Crabb, D Crannell, H Cummings, J Degtiarenko, PV Denizli, H Dennis, LC De Sanctis, E DeVita, R Dharmawardane, KV Djalali, C Dodge, GE Dore, D Doughty, D Dragovitsch, P Dytman, S Eckhause, M Egiyan, H Egiyan, KS Empl, A Fatemi, R Feuerbach, RJ Ficenec, J Fissum, K Forest, TA Freyberger, AP Funsten, H Gaff, S Gai, M Garcon, M Gavalian, G Gilad, S Gilfoyle, GP Giovanetti, K Girard, P Griffioen, KA Guidal, M Guillo, M Gyurjyan, V Hadjidakis, C Hardie, J Heddle, D Hersman, FW Hicks, K Hicks, RS Holtrop, M Hu, J Hyde-Wright, CE Ito, MM Jenkins, D Joo, K Kelley, J Khandaker, M Kim, DH Kim, K Kim, KY Kim, W Klein, A Klein, FJ Klusman, M Kossov, M Kramer, LH Kuhn, SE Laget, JM Lawrence, D Longhi, A Lukashin, K Manak, JJ Marchand, C McAleer, S McCarthy, J McNabb, JWC Mecking, BA Mestayer, MD Meyer, CA Mikhailov, K Minehart, R Mirazita, M Miskimen, R Morand, L Muccifora, V Mueller, J Mutchler, GS Napolitano, J Nelson, S Niccolai, S Niculescu, G Niculescu, I Niyazov, RA Opper, A O'Rielly, G O'Brien, JT Park, K Pasyuk, E Peterson, GA Philips, S Pivnyuk, N Pocanic, D Pogorelko, O Polli, E Popa, I Pozdniakov, S Preedom, BM Price, JW Protopopescu, D Qin, LM Raue, BA Reolon, AR Riccardi, G Ricco, G Ripani, M Ritchie, BG Ronchetti, F Rossi, P Rowntree, D Rubin, PD Sabatie, F Sabourov, K Salgado, CW Sapunenko, V Schumacher, RA Serov, V Sharabian, YG Shaw, J Simionatto, S Skabelin, A Smith, ES Smith, LC Sober, DI Stavinsky, A Stoler, P Strakovsky, II Suleiman, R Taiuti, M Taylor, S Tedeschi, D Thompson, R Todor, L Vineyard, MF Vlassov, A Wang, K Weller, H Weinstein, LB Welsh, R Weygand, DP Whisnant, S Wolin, E Yegneswaran, A Yun, J Zhao, J Zhang, B Zhou, Z
Citation
S. Stepanyan et al., Observation of exclusive deeply virtual Compton scattering in polarized electron beam asymmetry measurements - art. no. 182002, PHYS REV L, 8718(18), 2001, pp. 2002
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
0031-9007 → ACNP
Volume
8718
Issue
18
Year of publication
2001
Database
ISI
SICI code
0031-9007(20011029)8718:18<2002:OOEDVC>2.0.ZU;2-U
Abstract
We report the first results of the beam-spin asymmetry measured in the reac tion (e) over right arrowp --> ep gamma at a beam energy of 4.25 GeV. A lar ge asymmetry with a sin phi modulation is observed, as predicted for the in terference term of deeply virtual compton scattering (DVCS) and the Bethe-H eitler process. The amplitude of this modulation is alpha = 0.202 +/- 0.028 . In leading-order and leading-twist perturbative QCD, the alpha is directl y proportional to the imaginary part of the DVCS amplitude.