First measurement of the helicity asymmetry E in η photoproduction on the proton

Autor: K. A. Griffioen, K. Livingston, B. McKinnon, H. Hakobyan, C. Hanretty, S. Strauch, Latifa Elouadrhiri, C. A. Meyer, G. V. Fedotov, E. De Sanctis, I. Bedlinskiy, S. Chandavar, L. Colaneri, J. Brock, K. P. Adhikari, E. Golovatch, R. Dupre, D. I. Sober, M. C. Kunkel, V. Batourine, M. L. Seely, I. Zonta, Iu. Skorodumina, X. Wei, V. Crede, S. Pisano, Victor Mokeev, I. I. Strakovsky, E. Voutier, F. Sabatié, M. Ripani, D. I. Glazier, H. Egiyan, M. Ungaro, A. Deur, R. A. Montgomery, P. Stoler, Barry Ritchie, A. Simonyan, I. Senderovich, P. Lenisa, Z. W. Zhao, R. De Vita, Diane Schott, W. K. Brooks, A. El Alaoui, Y. Ilieva, K. Hicks, H. S. Jo, K. L. Giovanetti, Gerard Gilfoyle, K. Joo, C. D. Keith, Nicholas Zachariou, K. Park, N. K. Walford, D. G. Ireland, L. Guo, D. G. Jenkins, H. Jiang, Volker D. Burkert, A. S. Biselli, Sylvester Joosten, Michael Dugger, I. J. D. MacGregor, S. Anefalos Pereira, V. P. Kubarovsky, R. A. Badui, S. Park, N. Dashyan, A. Filippi, F. X. Girod, O. Pogorelko, S. M. Hughes, J. Zhang, W. Phelps, P. Nadel-Turonski, M. Khandaker, O. Cortes, W. Gohn, A. Celentano, R. W. Gothe, Ye Tian, Dustin Keller, Friedrich Klein, S. Boiarinov, D. G. Meekins, A. D'Angelo, J. W. Price, C. Djalali, Michael Wood, K. Hafidi, D. Rönchen, E. Seder, M. Contalbrigo, P. Mattione, P. Peng, L. El Fassi, C. Munoz Camacho, J. T. Goetz, R. Tucker, H. Voskanyan, P. L. Cole, E. Pasyuk, Z. Akbar, Lorenzo Zana, J. P. Ball, Y. Prok, P. Roy, D. Adikaram, M. Guidal, D. S. Carman, A. Rizzo, S. Niccolai, C. Salgado, G. D. Smith, M. Holtrop, A. Movsisyan, M. Battaglieri, S. Fegan, A. Kim, G. Charles, T. Mineeva, B. Morrison, V. Sytnik, P. Eugenio, B. S. Ishkhanov, R. A. Schumacher, P. Collins, B. Garillon, Michael Döring, D. Ho, S. Stepanyan, A. Fradi, H. Y. Lu, Andrew Puckett, Nikolaos Sparveris, I. Niculescu, J. A. Fleming, L. A. Net, C. Carlin, G. Rosner, M. Osipenko, Y. Ghandilyan, G. Khachatryan, W. J. Briscoe, G. Niculescu, M. Hattawy, N. A. Baltzell
Přispěvatelé: 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, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), CLAS Collaboration, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Jazyk: angličtina
Rok vydání: 2016
Předmět:
Zdroj: Physics Letters B
Physics Letters B, 2016, 755, pp.64-69. ⟨10.1016/j.physletb.2016.01.044⟩
Physics Letters B, Elsevier, 2016, 755, pp.64-69. ⟨10.1016/j.physletb.2016.01.044⟩
Physics letters / B 755, 64–69 (2016). doi:10.1016/j.physletb.2016.01.044
Physics Letters B, Vol 755, Iss, Pp 64-69 (2016)
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2016.01.044⟩
Popis: Results are presented for the first measurement of the double-polarization helicity asymmetry E for the η photoproduction reaction γp→ηp. Data were obtained using the FROzen Spin Target (FROST) with the CLAS spectrometer in Hall B at Jefferson Lab, covering a range of center-of-mass energy W from threshold to 2.15 GeV and a large range in center-of-mass polar angle. As an initial application of these data, the results have been incorporated into the Jülich–Bonn model to examine the case for the existence of a narrow N⁎ resonance between 1.66 and 1.70 GeV. The addition of these data to the world database results in marked changes in the predictions for the E observable from that model. Further comparison with several theoretical approaches indicates these data will significantly enhance our understanding of nucleon resonances. Keywords: Eta photoproduction, Polarization observable, Helicity asymmetry
Databáze: OpenAIRE