Measurement of Proton Electromagnetic Form Factors in e + e − → p p ¯ in the Energy Region 2.00–3.08 GeV

Ablikim, M.; Achasov, M. N.; Adlarson, P.; Ahmed, S.; Albrecht, M.; Alekseev, M.; Amoroso, A.; An, F. F.; An, Q.; Anita,; Bai, Y.; Bakina, O.; Baldini Ferroli, R.; Balossino, I.; Ban, Y.; Begzsuren, K.; Bennett, J. V.; Berger, N.; Bertani, M.; Bettoni, D.; Bianchi, F.; Biernat, J.; Bloms, J.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Calcaterra, A.; Cao, G. F.; Cao, N.; Cetin, S. A.; Chai, J.; Chang, J. F.; Chang, W. L.; Chelkov, G.; Chen, D. Y.; Chen, G.; Chen, H. S.; Chen, J.; Chen, M. L.; Chen, S. J.; Chen, X. R.; Chen, Y. B.; Cheng, W.; Cibinetto, G.; Cossio, F.; Cui, X. F.; Dai, H. L.; Dai, J. P.; Dai, X. C.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Fang, Y.; Farinelli, R.; Fava, L.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fritsch, M.; Fu, C. D.; Fu, Y.; Gao, Q.; Gao, Y.; Gao, Y.; Gao, Y. G.; Garillon, B.; Garzia, I.; Gersabeck, E. M.; Gilman, A.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, L. M.; Gu, M. H.; Gu, S.; Gu, Y. T.; Guan, C. Y.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y. P.; Guskov, A.; Han, S.; Han, T. Z.; Hao, X. Q.; Harris, F. A.; He, K. L.; Heinsius, F. H.; Held, T.; Heng, Y. K.; Himmelreich, M.; Hou, Y. R.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, L. Q.; Huang, X. T.; Huesken, N.; Hussain, T.; Ikegami Andersson, W.; Imoehl, W.; Irshad, M.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, H. L.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jin, Y.; Johansson, T.; Kalantar-Nayestanaki, N.; Kang, X. S.; Kappert, R.; Kavatsyuk, M.; Ke, B. C.; Keshk, I. K.; Khoukaz, A.; Kiese, P.; Kiuchi, R.; Kliemt, R.; Koch, L.; Kolcu, O. B.; Kopf, B.; Kuemmel, M.; Kuessner, M.; Kupsc, A.; Kurth, M.; Kurth, M. G.; Kühn, W.; Lange, J. S.; Larin, P.; Lavezzi, L.; Leithoff, H.; Lenz, T.; Li, C.; Li, C. H.; Li, Cheng; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Ke; Li, L. K.; Li, Lei; Li, P. L.; Li, P. R.; Li, W. D.; Li, W. G.; Li, X. H.; Li, X. L.; Li, X. N.; Li, Z. B.; Li, Z. Y.; Liang, H.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, L. Z.; Libby, J.; Lin, C. X.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, D. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. M.; Liu, Huanhuan; Liu, Huihui; Liu, J. B.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, Ke; Liu, L.; Liu, L. Y.; Liu, Q.; Liu, S. B.; Liu, T.; Liu, X.; Liu, X. Y.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Long, Y. F.; Lou, X. C.; Lu, H. J.; Lu, J. D.; Lu, J. G.; Lu, X. L.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, P. W.; Luo, T.; Luo, X. L.; Lusso, S.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, R. Q.; Ma, X. N.; Ma, X. X.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Maldaner, S.; Malde, S.; Malik, Q. A.; Mangoni, A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Meng, Z. X.; Messchendorp, J. G.; Mezzadri, G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Mustafa, A.; Nakhoul, S.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Papenbrock, M.; Pathak, A.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Pitka, A.; Poling, R.; Prasad, V.; Qi, H.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, X. P.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Qu, S. Q.; Rashid, K. H.; Ravindran, K.; Redmer, C. F.; Richter, M.; Rivetti, A.; Rodin, V.; Rolo, M.; Rong, G.; Rosner, Ch.; Rump, M.; Sarantsev, A.; Savrié, M.; Schelhaas, Y.; Schoenning, K.; Shan, W.; Shan, X. Y.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, H. C.; Shi, R. S.; Shi, X.; Shi, X. D.; Song, J. J.; Song, Q. Q.; Song, X. Y.; Sosio, S.; Sowa, C.; Spataro, S.; Sui, F. F.; Sun, G. X.; Sun, J. 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doi:10.1103/PhysRevLett.124.042001

Title: Measurement of Proton Electromagnetic Form Factors in $e^{+} e^{-} \to p \bar{p}$ in the Energy Region 2.00–3.08 GeV

Journal Article · Tue Jan 28 00:00:00 EST 2020 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.124.042001· OSTI ID:1595514

Ablikim, M.; Achasov, M. N.; Adlarson, P.; Ahmed, S.; Albrecht, M.; Alekseev, M.; Amoroso, A.; An, F. F.; An, Q.; Anita,; Bai, Y.; Bakina, O.; Baldini Ferroli, R.; Balossino, I.; Ban, Y.; Begzsuren, K.; Bennett, J. V.; Berger, N.; Bertani, M.; Bettoni, D. more »

The process of $$e^+e^– → p\bar{p}$$ is studied at 22 center-of-mass energy points ($$\sqrt{s}$$) from 2.00 to 3.08 GeV, exploiting 688.5 pb^–1 of data collected with the BESIII detector operating at the BEPCII collider. The Born cross section ($$σ_{p\bar{p}}$$) of $$e^+e^– → p\bar{p}$$ is measured with the energy-scan technique and it is found to be consistent with previously published data, but with much improved accuracy. In addition, the electromagnetic form-factor ratio (|$$G_E/G_M$$|) and the value of the effective (|$$G_{\text{eff}}$$|), electric (|$$G_E$$|), and magnetic (|$$G_M$$|) form factors are measured by studying the helicity angle of the proton at 16 center-of-mass energy points. |$$G_E/G_M$$| and |$$G_M$$| are determined with high accuracy, providing uncertainties comparable to data in the spacelike region, and |$$G_E$$| is measured for the first time. We reach unprecedented accuracy, and precision results in the timelike region provide information to improve our understanding of the proton inner structure and to test theoretical models which depend on nonperturbative quantum chromodynamics.

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Research Organization:: Indiana Univ., Bloomington, IN (United States); Carnegie Mellon Univ., Pittsburgh, PA (United States); Univ. of Hawaii, Honolulu, HI (United States); Univ. of Minnesota, Minneapolis, MN (United States)

Sponsoring Organization:: USDOE Office of Science (SC)

Contributing Organization:: BESIII Collaboration

Grant/Contract Number:: FG02-05ER41374; SC-0010118; SC-0010504; SC-0012069; SC0010118; SC0010504; SC0012069

OSTI ID:: 1595514

Alternate ID(s):: OSTI ID: 1800279

Journal Information:: Physical Review Letters, Journal Name: Physical Review Letters Vol. 124 Journal Issue: 4; ISSN 0031-9007

Publisher:: American Physical SocietyCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 33 works

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