Observation of a Coherence Length Effect in Exclusive {rho}{sup 0} Electroproduction

Journal Article · Thu Apr 01 04:00:00 EST 1999 · Physical Review Letters

OSTI ID:347062

Galumian, P; Green, P W; Greeniaus, L G; Kitching, P; Martens, F K; Miller, C A ^[1]; Gao, H; Hansen, J; Jackson, H E; Jones, C; Makins, N C; ONeill, T G; Potterveld, D H ^[2]; Bray, B; Carter, P; Dvoredsky, A; Filippone, B W; Korsch, W; Lung, A; McIlhany, K ; McKeown, R D; Pitt, M ^[3]; Belz, J E; Brack, J; Ely, J; Fox, B; Kinney, E; Mercer, D; Rakness, G; Ristinen, R ^[4]; Ackerstaff, K; Funk, M; Holler, Y; Ihssen, H; Meyners, N; Roeper, G; Schueler, K P; Sinram, K; Spengos, M; Woller, K; Zapfe-Dueren, K ^[5]; Akushevich, I; Aschenauer, E C; Boettcher, H; Borissov, A; Brons, S; Gaerber, Y; Hasch, D; Korotkov, V; Krause, B; Meissner, F; Nowak, W; Roloff, H; Schwind, A; Stoesslein, U ^[6]; Fechtchenko, A; Gagunashvili, N D; Krivokhijine, V G; Mitsyn, V; Nagaitsev, A; Savin, I; Shutov, V ^[7]; Benisch, T; Bernreuther, S; Braun, B; Dueren, M; Ferstl, M; Fiedler, K; Grosshauser, C; Gute, A; Henoch, M; Kirsch, M; Lachnit, W; Neunreither, F; Rith, K; Schmidt, F; Steffens, E; Stenger, J; Stock, F; Wander, W; Woelfel, T ^[8]; Dalpiaz, P F; Frabetti, S; Masoli, F; Reali, A; Simani, C; Slavich, P ^[9]; Avakian, H; Bianchi, N; Capitani, G P; De Sanctis, E; Di Nezza, P; Fantoni, A; Giordjian, V; Gyurjyan, V; others, and

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1. Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada)
2. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439-4843 (United States)
3. W. K. Kellogg Radiation Lab, California Institute of Technology, Pasadena, California 91125 (United States)
4. Nuclear Physics Laboratory, University of Colorado, Boulder, Colorado 80309-0446 (United States)
5. DESY, Deutsches Elektronen Synchrotron, D-22603 Hamburg (Germany)
6. DESY Zeuthen, D-15738 Zeuthen (Germany)
7. Joint Institute for Nuclear Research, 141980 Dubna (Russia)
8. Physikalisches Institut, Universitaet Erlangen-Nuernberg, D-91058 Erlangen (Germany)
9. Dipartimento di Fisica, Universita di Ferrara, I-44100 Ferrara (Italy)

Exclusive incoherent electroproduction of the {rho}{sup 0}{number_sign}770 meson from {sup 1}H , {number_sign}{sup 2}H , {number_sign}{sup 3}He , and {number_sign}{sup 14}N targets has been studied by the HERMES experiment at squared four-momentum transfer Q{sup 2}{gt}0.4 GeV{sup 2} and positron energy loss {nu} from 9 to 20 GeV. The ratio of the {number_sign}{sup 14}N to {number_sign}{sup 1}H cross sections per nucleon, known as the nuclear transparency, was found to decrease with increasing coherence length of quark-antiquark fluctuations of the virtual photon. The data provide clear evidence of the interaction of the quark-antiquark fluctuations with the nuclear medium. {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 347062
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 15 Vol. 82; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CROSS SECTIONS
DEUTERONS
ELECTRON REACTIONS
NITROGEN
NITROGEN 14
NUCLEAR MATTER
PARTICLE PRODUCTION
PROTONS
QUARK-ANTIQUARK INTERACTIONS
QUARKS
RHO-770 MESONS
TRITONS