Measurement of the beam spin asymmetry of e→p→e′p′η in the deep-inelastic regime with CLAS

Zhao, B. et al. (2019) Measurement of the beam spin asymmetry of e→p→e′p′η in the deep-inelastic regime with CLAS. Physics Letters B, 789, pp. 426-431. (doi: 10.1016/j.physletb.2018.12.065)

Abstract

The beam spin asymmetry of the exclusive pseudoscalar channel e→p→e′p′η was measured for the first time in the deep-inelastic regime (W > 2 GeV/c2 and Q2 > GeV2/C2) using a longitudinally polarized 5.78 GeV electron beam at Jefferson Lab with the CEBAF Large Acceptance Spectrometer. The data were accumulated in 144 four-dimensional bins of Q2, Xb, −t and ϕ over a wide kinematic range, where ϕ is the azimuthal angle between the lepton and hadron scattering planes, The measured azimuthal dependence with large amplitudes of the moments is a clear indication of a substantial contribution to the polarized cross-section from transversely polarized virtual photons. In the framework of generalized parton distributions (GPDs) this contribution is expressed via longitudinal-transverse interference between chiral-even and chiral-odd GPDs. The experimental results are compared to the existing theoretical models demonstrating the sensitivity to the product of chiral-odd and chiral-even GPDs and provide new constraints to the existing GPD parameterizations.

• Item Type: Articles
• Additional Information: This work was supported in part by the U.S. Department of Energy (No. DE-FG02-96ER40950), the National Science Foundation, the French Centre National de la Recherche Scientifique and Commissariat à l'Energie Atomique, the French-American Cultural Exchange (FACE), the Italian Instituto Nazionale di Fisica Nucleare (INFN), the Chilean Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), the National Research Foundation of Korea, and the UK Science and Technology Facilities Council (STFC). Jefferson Science Associates (JSA) operates the Thomas Jefferson National Accelerator Facility for the United States Department of Energy under contract DE-AC05-06OR23177.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sokhan, Dr Daria and Protopopescu, Dr Dan and MacGregor, Professor Douglas 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: Zhao, B., Kim, A., Joo, K., Bedlinskiy, I., Kim, W., Kubarovsky, V., Ungaro, M., Adhikari, S., Akbar, Z., Angelini, G., Avakian, H., Ball, J., Baltzell, N.A., Barion, L., Bashkanov, M., Battaglieri, M., Batourine, V., Biselli, A.S., Boiarinov, S., Briscoe, W.J., Brooks, W.K., Burkert, V.D., Carman, D.S., Celentano, A., Chatagnon, P., Chetry, T., Ciullo, G., Clark, L., Clary, B.A., Cole, P.L., Contalbrigo, M., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Defurne, M., Deur, A., Diehl, S., Djalali, C., Dupre, R., Egiyan, H., Ehrhart, M., El Alaoui, A., El Fassi, L., Eugenio, P., Filippi, A., Forest, T.A., Gavalian, G., Ghandilyan, Y., Gilfoyle, G.P., Girod, F.X., Golovatch, E., Gothe, R.W., Griffioen, K.A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Holtrop, M., Ilieva, Y., Ireland, D.G., Ishkhanov, B.S., Isupov, E.L., Jenkins, D., Jo, H.S., Johnston, S., Kabir, M.L., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Klein, A., Klein, F.J., Kuhn, S.E., Kuleshov, S.V., Lanza, L., Lenisa, P., Livingston, K., MacGregor, I.J.D., Marchand, D., Markov, N., McKinnon, B., Meyer, C.A., Meziani, Z.E., Mirazita, M., Mokeev, V., Montgomery, R.A., Munoz Camacho, C., Nadel-Turonski, P., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A.I., Paolone, M., Paremuzyan, R., Park, K., Pogorelko, O., Price, J.W., Prok, Y., Protopopescu, D., Ripani, M., Rizzo, A., Rosner, G., Rossi, P., Sabatié, F., Salgado, C., Schumacher, R.A., Sharabian, Y.G., Skorodumina, I., Smith, G.D., Sokhan, D., Sparveris, N., Stepanyan, S., Strakovsky, I.I., Strauch, S., Taiuti, M., Tan, J.A., Voskanyan, H., Voutier, E., Wang, R., Wei, X., Wood, M.H., Zachariou, N., Zhang, J., and Zhao, Z.W.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physics Letters B
• Publisher: Elsevier
• ISSN: 0370-2693
• ISSN (Online): 1873-2445
• Published Online: 03 January 2019
• Copyright Holders: Copyright © 2019 The Authors
• First Published: First published in Physics Letters B 789: 426-431
• Publisher Policy: Reproduced under a Creative Commons License