학술논문

The Beam-Target Helicity Asymmetry for $\vec{\gamma} \vec{n} \rightarrow \pi^- p$ in the {\bf{$N^*$} Resonance Region
Document Type
Working Paper
Author
Ho, D.Peng, P.Bass, C.Collins, P.D'Angelo, A.Deur, A.Fleming, J.Hanretty, C.Kageya, T.Khandaker, M.Klein, F. J.Klempt, E.Laine, V.Lowry, M. M.Lu, H.Nepali, C.Nikonov, V. A.O'Connell, T.Sandorfi, A. M.Sarantsev, A. V.Schumacher, R. A.Strakovsky, I. I.Švarc, A.Walford, N. K.Wei, X.Whisnant, C. S.Workman, R. L.Zonta, I.Adhikari, K. P.Adikaram, D.Akbar, Z.Amaryan, M. J.Pereira, S. AnefalosAvakian, H.Ball, J.Bashkanov, M.Battaglieri, M.Batourine, V.Bedlinskiy, I.Briscoe, W. J.Burkert, V. D.Carman, D. S.Celentano, A.Charles, G.Chetry, T.Ciullo, G.Clark, L.Colaneri, L.Cole, P. L.Contalbrigo, M.Crede, V.Dashyan, N.De Sanctis, E.De Vita, R.Djalali, C.Dupre, R.Alaoui, A. ElFassi, L. ElElouadrhiri, L.Fedotov, G.Fegan, S.Fersch, R.Filippi, A.Fradi, A.Ghandilyan, Y.Gilfoyle, G. P.Girod, F. X.Glazier, D. I.Gleason, C.Gohn, W.Golovatch, E.Gothe, R. W.Griffioen, K. A.Guidal, M.Guo, L.Hakobyan, H.Harrison, N.Hicks, K.Holtrop, M.Hughes, S. M.Ilieva, Y.Ireland, D. G.Ishkhanov, B. S.Isupov, E. L.Jenkins, D.Jiang, H.Jo, H. S.Joo, K.Joosten, S.Keller, D.Khachatryan, G.Kim, A.Kim, W.Klein, A.Kubarovsky, V.Kuleshov, S. V.Lanza, L.Lenisa, P.Livingston, K.MacGregor, I . J . D.Markov, N.McKinnon, B.Mineeva, T.Mokeev, V.Montgomery, R. A.Movsisyan, ACamacho, C. MunozMurdoch, G.Niccolai, S.Niculescu, G.Osipenko, M.Paolone, M.Paremuzyan, R.Park, K.Pasyuk, E.Phelps, W.Pogorelko, O.Price, J. W.Procureur, S.Protopopescu, D.Ripani, M.Riser, D.Ritchie, B. G.Rizzo, A.Rosner, G.Sabatié, F.Salgado, C.Sharabian, Y. G.Skorodumina, Iu.Smith, G. D.Sober, D. I.Sokhan, D.Sparveris, N.Strauch, S.Tian, YeTorayev, B.Ungaro, M.Voskanyan, H.Watts, D. P.Wood, M. H.Zachariou, N.Zhang, J.Zhao, Z. W.
Source
Subject
Nuclear Experiment
Language
Abstract
We report the first beam-target double-polarization asymmetries in the $\gamma + n(p) \rightarrow \pi^- + p(p)$ reaction spanning the nucleon resonance region from invariant mass $W$= $1500$ to $2300$ MeV. Circularly polarized photons and longitudinally polarized deuterons in $H\!D$ have been used with the CLAS detector at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the {\it{E}} polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses, and have led to significant revisions for several $\gamma nN^*$ resonance photo-couplings.
Comment: 6 pages, 5 figures; Physical Review Letters - in press