Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1GeV2 . I. ep→eπ+n

Bosted, P. E. et al. (2017) Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1GeV2 . I. ep→eπ+n. Physical Review C, 95(3), 035206. (doi:10.1103/PhysRevC.95.035206)

[img]
Preview
Text
139292.pdf - Accepted Version

1MB

Abstract

Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π + electroproduction reaction γ ∗ p → n π + . The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic range covered is 1.1 < W < 3 GeV and 1 < Q 2 < 6 GeV 2 . Results were obtained for about 6000 bins in W ,   Q 2 ,   cos ( θ ∗ ) , and ϕ ∗ . Except at forward angles, very large target-spin asymmetries are observed over the entire W region. Reasonable agreement is found with phenomenological fits to previous data for W < 1.6 GeV, but very large differences are seen at higher values of W . A generalized parton distributions (GPD)-based model is in poor agreement with the data. When combined with cross-sectional measurements, the present results provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q 2 , for resonances with masses as high as 2.4 GeV.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Sokhan, Dr Daria and Protopopescu, Dr Dan and MacGregor, Professor I and Murdoch, Mr Gavin and McKinnon, Dr Bryan and Clark, Ms Louise and Livingston, Dr Kenneth and Montgomery, Dr Rachel and Ireland, Professor David and Rosner, Professor Guenther
Authors: Bosted, P. E., Amaryan, M. J., Anefalos Pereira, S., Avakian, H., Badui, R. A., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Briscoe, W. J., Bültmann, S., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Ciullo, G., Clark, L., Colaneri, L., Cole, P. L., Contalbrigo, M., Crede, V., D'Angelo, A., De Vita, R., Deur, A., De Sanctis, E., Djalali, C., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fanchini, E., Fedotov, G., Filippi, A., Fleming, J. A., Forest, T., Fradi, A., Gevorgyan, N., Ghandilyan, Y., Gilfoyle, G. P., Girod, F. X., Gleason, C., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Hakobyan, H., Hattawy, M., Hicks, K., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jiang, H., Jo, H. S., Joo, K., Joosten, S., Khachatryan, G., Khandaker, M., Kim, A., Kim, W., Klein, F. J., Koirala, S., Kubarovsky, V., Kuhn, S. E., Lanza, L., Net, L. A., Lenisa, P., Livingston, K., MacGregor, I. J. D., McCracken, M. E., McKinnon, B., Meyer, C. A., Mirazita, M., Mokeev, V. I., Montgomery, R. A., Munevar, E., Munoz Camacho, C., Murdoch, G., Nadel-Turonski, P., Niccolai, S., Osipenko, M., Ostrovidov, A. I., Park, K., Pasyuk, E., Peng, P., Phelps, W., Pisano, S., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Puckett, A. J. R., Raue, B. A., Ripani, M., Rosner, G., Rossi, P., Schumacher, R. A., Seder, E., Skorodumina, I., Smith, G. D., Sokhan, D., Sparveris, N., Stankovic, I., Stepanyan, S., Strakovsky, I. I., Strauch, S., Taiuti, M., Tian, Y., Torayev, B., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Wei, X., Weinstein, L. B., Zachariou, N., Zhang, J., Zhao, Z. W., and Zonta, I.
College/School:College of Science and Engineering > School of Physics and Astronomy
Journal Name:Physical Review C
Publisher:American Physical Society
ISSN:2469-9985
ISSN (Online):2469-9993
Published Online:20 March 2017
Copyright Holders:Copyright © 2017 American Physical Society
First Published:First published in Physical Review C 95(3): 035206
Publisher Policy:Reproduced in accordance with the publisher copyright policy
Related URLs:

University Staff: Request a correction | Enlighten Editors: Update this record