학술논문

Near Threshold Neutral Pion Electroproduction at High Momentum Transfers and Generalized Form Factors
Document Type
Working Paper
Author
Khetarpal, P.Stoler, P.Aznauryan, I. G.Kubarovsky, V.Adhikari, K. P.Adikaram, D.Aghasyan, M.Amaryan, M. J.Anderson, M. D.Pereira, S. AnefalosAnghinolfi, M.Avakian, H.Baghdasaryan, H.Ball, J.Baltzell, N. A.Battaglieri, M.Batourine, V.Bedlinskiy, I.Biselli, A. S.Bono, J.Boiarinov, S.Briscoe, W. J.Brooks, W. K.Burkert, V. D.Carman, D. S.Celentano, A.Charles, G.Cole, P. L.Contalbrigo, M.Crede, V.D'Angelo, A.Dashyan, N.De Vita, R.De Sanctis, E.Deur, A.Djalali, C.Doughty, D.Dugger, M.Dupre, R.Egiyan, H.Alaoui, A. ElFassi, L. ElEugenio, P.Fedotov, G.Fegan, S.Fersch, R.Fleming, J. A.Fradi, A.Gabrielyan, M. Y.Garçon, M.Gevorgyan, N.Gilfoyle, G. P.Giovanetti, K. L.Girod, F. X.Goetz, J. T.Gohn, W.Golovatch, E.Gothe, R. W.Griffioen, K. A.Guegan, B.Guidal, M.Guo, L.Hafidi, K.Hakobyan, H.Hanretty, C.Harrison, N.Hicks, K.Ho, D.Holtrop, M.Hyde, C. E.Ilieva, Y.Ireland, D. G.Ishkhanov, B. S.Isupov, E. L.Jo, H. S.Joo, K.Keller, D.Khandaker, M.Kim, A.Kim, W.Klein, F. J.Koirala, S.Kubarovsky, A.Kuleshov, S. V.Kvaltine, N. D.Lewis, S.Livingston, K.Lu, H. Y.MacGregor, I. J. D.Mao, Y.Martinez, D.Mayer, M.McKinnon, B.Meyer, C. A.Mineeva, T.Mirazita, M.Mokeev, V.Montgomery, R. A.Moutarde, H.Munevar, E.Camacho, C. MunozNadel-Turonski, P.Nasseripour, R.Niccolai, S.Niculescu, G.Niculescu, I.Osipenko, M.Ostrovidov, A. I.Pappalardo, L. L.Paremuzyan, R.Park, K.Park, S.Pasyuk, E.Phelps, E.Phillips, J. J.Pisano, S.Pogorelko, O.Pozdniakov, S.Price, J. W.Procureur, S.Protopopescu, D.Puckett, A. J. R.Raue, B. A.Ricco, G.Rimal, D.Ripani, M.Rosner, G.Rossi, P.Sabatié, F.Saini, M. S.Salgado, C.Saylor, N. A.Schott, D.Schumacher, R. A.Seder, E.Seraydaryan, H.Sharabian, Y. G.Smith, G. D.Sober, D. I.Sokhan, D.Stepanyan, S. S.Stepanyan, S.Strakovsky, I. I.Strauch, S.Taiuti, M.Tang, W.Taylor, C. E.Tkachenko, S.Ungaro, M.Vernarsky, B.Voskanyan, H.Voutier, E.Walford, N. K.Weinstein, L. B.Weygand, D. P.Wood, M. H.Zachariou, N.Zhang, J.Zhao, Z. W.Zonta, I.
Source
Phys. Rev. C 87, 045205 (2013)
Subject
Nuclear Experiment
Language
Abstract
We report the measurement of near threshold neutral pion electroproduction cross sections and the extraction of the associated structure functions on the proton in the kinematic range $Q^2$ from 2 to 4.5 GeV$^2$ and $W$ from 1.08 to 1.16 GeV. These measurements allow us to access the dominant pion-nucleon s-wave multipoles $E_{0+}$ and $S_{0+}$ in the near-threshold region. In the light-cone sum-rule framework (LCSR), these multipoles are related to the generalized form factors $G_1^{\pi^0 p}(Q^2)$ and $G_2^{\pi^0 p}(Q^2)$. The data are compared to these generalized form factors and the results for $G_1^{\pi^0 p}(Q^2)$ are found to be in good agreement with the LCSR predictions, but the level of agreement with $G_2^{\pi^0 p}(Q^2)$ is poor.
Comment: 17 pages, 18 figures, Journal article (Physical Review C)