Form factors and two-photon exchange in high-energy elastic electron-proton scattering

Christy, M.E. et al. (2022) Form factors and two-photon exchange in high-energy elastic electron-proton scattering. Physical Review Letters, 128(10), 102002. (doi: 10.1103/PhysRevLett.128.102002)

Abstract

We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q2) up to 15.75  (GeV/c)2. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q2 and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q2 and attributed to hard two-photon exchange (TPE) effects, extending to 8  (GeV/c)2 the range of Q2 for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q2.

• Item Type: Articles
• Additional Information: This work was supported in part by the Science Committee of Republic of Armenia under Grant No. 21AG-1C085, the Natural Sciences and Engineering Research Council of Canada (NSERC), the UK Science and Technology Facilities Council (Grants No. STFC 57071/1 and No. STFC 50727/1), the U.S. National Science Foundation Grant No. PHY-1508272, and the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contracts No. DE-AC02-05CH11231, No. DEAC02-06CH11357, and No. DE-SC0016577, and DOE Contract No. DE-AC05-06OR23177, under which Jefferson Science Association, LCC operates JLab.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Annand, Dr John and Hamilton, Dr David and Montgomery, Dr Rachel
• Authors: Christy, M.E., Gautam, T., Ou, L., Schmookler, B., Wang, Y., Adikaram, D., Ahmed, Z., Albataineh, H., Ali, S.F., Aljawrneh, B., Allada, K., Allison, S.L., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Arrington, J., Atac, H., Averett, T., Ayerbe Gayoso, C., Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Bhatt, H., Bhetuwal, D., Biswas, D., Brash, E., Bulumulla, D., Camacho, C.M., Campbell, J., Camsonne, A., Carmignotto, M., Castellanos, J., Chen, C., Chen, J.-P., Chetry, T., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J.C., Covrig Dusa, S., Crowe, B., Danagoulian, S., Danley, T., Deconinck, W., Defurne, M., Desnault, C., Di, D., Dlamini, M., Duer, M., Duran, B., Ent, R., Fanelli, C., Fuchey, E., Gal, C., Gaskell, D., Georges, F., Gilad, S., Glamazdin, O., Gnanvo, K., Gramolin, A.V., Gray, V.M., Gu, C., Habarakada, A., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Hernandez, A.V., Henry, W., Higinbotham, D.W., Holmstrom, T., Horn, T., Huang, Y., Huber, G.M., Hyde, C., Ibrahim, H., Israel, N., Jen, C.-M., Jin, K., Jones, M., Kabir, A., Karki, B., Keppel, C., Khachatryan, V., King, P.M., Li, S., Li, W., Liu, H., Liu, J., Liyanage, A.H., Mack, D., Magee, J., Malace, S., Mammei, J., Markowitz, P., Mayilyan, S., McClellan, E., Meddi, F., Meekins, D., Mesick, K., Michaels, R., Mkrtchyan, A., Moffit, B., Montgomery, R., Myers, L.S., Nadel-Turonski, P., Nazeer, S.J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obrecht, R.F., Ohanyan, K., Palatchi, C., Pandey, B., Park, K., Park, S., Peng, C., Persio, F.D., Pomatsalyuk, R., Pooser, E., Puckett, A.J.R., Punjabi, V., Quinn, B., Rahman, S., Rashad, M.N.H., Reimer, P.E., Riordan, S., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N.H., Shabestari, M.H., Shahinyan, A., Širca, S., Smith, G.R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Stefanko, A., Su, T., Subedi, A., Sulkosky, V., Sun, A., Tan, Y., Thorne, L., Ton, N., Tortorici, F., Trotta, R., Uniyal, R., Urciuoli, G.M., Voutier, E., Waidyawansa, B., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z.H., Yero, C., Zhang, J., Zhao, Y.X., and Zhu, P.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physical Review Letters
• Publisher: American Physical Society
• ISSN: 0031-9007
• ISSN (Online): 1079-7114
• Copyright Holders: Copyright © 2022 American Physical Society
• First Published: First published in Physical Review Letters 128(10): 102002
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher