Target and beam-target spin asymmetries in exclusive pion electroproductionfor Q$^2$ > 1 GeV$^2$ . II. ep → e$\pi$$^0$p

Autor: Bosted, P, Kim, Seungmin, Adhikari, P, Adikaram, N, Akbar, S, Amaryan, N, Pereira, P, Avakian, N, Badui, M, Ball, J., Balossino, N, Battaglieri, N, Bedlinskiy, P, Biselli, B, Boiarinov, N, Briscoe, D, Brooks, M, Bültmann, N, Burkert, N, Cao, H, Carman, N, Celentano, N, Chandavar, S, Crede, S, D 'angelo, D, Dashyan, P, De Vita, N, De Sanctis, N, Deur, N, Djalali, D, Dupre, P, Egiyan, N, Alaoui, P, Fassi, Nizar, Elouadrhiri, N, Eugenio, P, Fanchini, N, Fedotov, G, Hafidi, N, Hakobyan, P, Hanretty, N, Harrison, N, Hattawy, N, Heddle, N, Hicks, H, Hollis, H, Holtrop, N, Hughes, E, Ireland, D, Isupov, P, Jenkins, D, Jiang, H, Jo, P, Joo, S, Keller, D, Khachatryan, P, Khandaker, P, Kim, N, Klei, N, Klein, D, Koirala, N, Kubarovsky, N, Kuhn, N, Lanza, N, Lenisa, P, Livingston, L, Lu, L, Macgregor, D, Markov, N, Mayer, N, Mccracken, P, Mckinnon, M, Mineeva, M, Mirazita, N, Mokeev, N, Montgomery, M, Movsisyan, N, Camacho, P, Murdoch, M, Nadel-Turonski, P, Ni, N, Niccolai, P, Niculescu, N, Osipenko, N, Ostrovidov, S, Paolone, P, Paremuzyan, P, Park, P, Pasyuk, P, Phelps, P, Pisano, P, Pogorelko, P, Price, P, Prok, P, Protopopescu, P, Puckett, P, Raue, N, Ripani, N, Rizzo, N, Rosner, G, Rossi, P, Roy, Philippe, Sabatié, F., Saini, M, Schumacher, P, Seder, E, Sharabian, N, Skorodumina, P, Smith, D, Sokhan, D, Sparveris, P, Stankovic, E, Stepanyan, N, Stoler, P, Strakovsky, D, Strauch, S, Taiuti, N, Tian, Ye, Torayev, N, Ungaro, N, Voskanyan, P, Voutier, P, Walford, N, Watts, P, Wei, N, Weinstein, N, Zachariou, N
Přispěvatelé: College of William and Mary [Williamsburg] (WM), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, The CLAS collaboration
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Physical Review C
Physical Review C, 2017, 95, pp.035207. ⟨10.1103/PhysRevC.95.035207⟩
Physical Review C, American Physical Society, 2017, 95, pp.035207. ⟨10.1103/PhysRevC.95.035207⟩
ISSN: 2469-9985
2469-9993
Popis: International audience; Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive pi(0) electroproduction reaction. gamma(*) p -> p pi(0), expanding an analysis of the. gamma(*) p -> n pi(+) reaction from the same experiment. 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 ranges covered are 1.1 < W < 3 GeV and 1 < Q(2) < 6 GeV2. Results were obtained for about 5700 bins in W, Q(2), cos(theta(*)), and phi(*). The beam-target asymmetries were found to generally be greater than zero, with relatively modest phi(*) dependence. The target asymmetries exhibit very strong phi(*) dependence, with a change in sign occurring between results at low W and high W, in contrast to pi(+) electroproduction. Reasonable agreement is found with phenomenological fits to previous data for W < 1.6 GeV, but significant differences are seen at higherW. When combined with cross-sectional measurements, as well as pi(+) observables, the present results will 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.
Databáze: OpenAIRE
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