Evidence for the onset of color transparency in rho(0) electroproduction off nuclei

/ Authors

Lamiaa El Fassi, L. Zana, K. Hafidi, M. Holtrop, B. Mustapha, W. Brooks, H. Hakobyan, X. Zheng, K. Adhikari, D. Adikaram

and 147 more authors

M. Aghasyan, M. Amaryan, M. Anghinolfi, J. Arrington, H. Avakian, H. Baghdasaryan, M. Battaglieri, V. Batourine, I. Bedlinskiy, A. Biselli, C. Bookwalter, D. Branford, W. Briscoe, S. Bultmann, V. Burkert, D. Carman, A. Celentano, S. Chandavar, P. Cole, M. Contalbrigo, V. Crede, A. D’Angelo, A. Daniel, N. Dashyan, R. Vita, E. Sanctis, A. Deur, B. Dey, R. Dickson, C. Djalali, G. Dodge, D. Doughty, R. Dupré, H. Egiyan, A. Alaoui, L. Elouadrhiri, P. Eugenio, G. Fedotov, S. Fegan, M. Gabrielyan, M. Garçon, N. Gevorgyan, G. Gilfoyle, K. Giovanetti, F. Girod, J. Goetz, W. Gohn, E. Golovatch, R. Gothe, K. Griffioen, M. Guidal, L. Guo, C. Hanretty, D. Heddle, K. Hicks, R. Holt, C. Hyde, Y. Ilieva, D. Ireland, B. Ishkhanov, E. Isupov, S. Jawalkar, D. Keller, M. Khandaker, P. Khetarpal, A. Kim, W. Kim, A. Klein, F. Klein, V. Kubarovsky, S. Kuhn, S. Kuleshov, V. Kuznetsov, J. Laget, H. Lu, I. MacGregor, Y. Mao, N. Markov, M. Mayer, J. Mcandrew, B. McKinnon, C. Meyer, T. Mineeva, M. Mirazita, V. Mokeev, B. Moreno, H. Moutarde, E. Munevar, P. Nadel-Turonski, A. Ni, S. Niccolai, G. Niculescu, I. Niculescu, M. Osipenko, A. Ostrovidov, L. Pappalardo, R. Paremuzyan, K. Park, S. Park, E. Pasyuk, S. Pereira, E. Phelps, S. Pisano, S. Pozdniakov, J. Price, S. Procureur, D. Protopopescu, B. Raue, P. Reimer, G. Ricco, D. Rimal, M. Ripani, B. Ritchie, G. Rosner, P. Rossi, F. Sabatié, M. Saini, C. Salgado, D. Schott, R. Schumacher, H. Seraydaryan, Y. Sharabian, E. Smith, G. Smith, D. Sober, D. Sokhan, S. Stepanyan, S. Stepanyan, P. Stoler, S. Strauch, M. Taiuti, W. Tang, C. E. Taylor, D. Tedeschi, S. Tkachenko, M. Ungaro, B. Vernarsky, M. Vineyard, H. Voskanyan, E. Voutier, D. Watts, L. Weinstein, D. Weygand, M. Wood, N. Zachariou, B. Zhao, Z. Zhao

/ Abstract

We have measured the nuclear transparency of the incoherent diffractive A(e,e' rho(0)) process in C-12 and Fe-56 targets relative to H-2 using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced rho(0,)s on a nucleus relative to deuterium, which is sensitive to rho A interaction, was studied as function of the coherence length (l(c)), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared (Q(2)). While the transparency for both C-12 and Fe-56 showed no lc dependence, a significant Q(2) dependence was measured, which is consistent with calculations that included the color transparency effects. (C) 2012 Elsevier B.V. All rights reserved.

Journal: Physics Letters B

DOI: 10.1016/j.physletb.2012.05.019