Branching ratio of the electromagnetic decay of the Σ^{+}(1385)

Keller, D.; Hicks, K.; Adhikari, K.; Adikaram, D.; Amaryan, M.; Anghinolfi, M.; Baghdasaryan, H.; Ball, J.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A.; Bookwalter, C.; Boiarinov, S.; Branford, D.; Briscoe, W.; Brooks, W.; Burkert, V.; Carman, D.; Celentano, A.; Chandavar, S.; Cole, P.; Contalbrigo, M.; Crede, V.; D’Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Djalali, C.; Doughty, D.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Gabrielyan, M.; Gevorgyan, N.; Gilfoyle, G.; Giovanetti, K.; Gohn, W.; Golovatch, E.; Gothe, R.; Graham, L.; Griffioen, K.; Guidal, M.; Guler, N.; Guo, L.; Hafidi, K.; Hakobyan, H.; Holtrop, M.; Ilieva, Y.; Ireland, D.; Ishkhanov, B.; Isupov, E.; Jo, H.; Joo, K.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, F.; Kubarovsky, A.; Kubarovsky, V.; Kuleshov, S.; Lu, H.; Macgregor, I.; Mao, Y.; Markov, N.; Mayer, M.; Mckinnon, B.; Meyer, C.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Moutarde, H.; Munevar, E.; Nadel Turonski, P.; Nasseripour, R.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A.; Paolone, M.; Pappalardo, L.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Procureur, S.; Prok, Y.; Protopopescu, D.; Raue, B.; Ricco, Giovanni; Rimal, D.; Ripani, M.; Ritchie, B.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M.; Salgado, C.; Schott, D.; Schumacher, R.; Seraydaryan, H.; Sharabian, Y.; Smith, E.; Smith, G.; Sober, D.; Sokhan, D.; Stepanyan, S.; Stepanyan, S.; Stoler, P.; Strauch, S.; Taiuti, MAURO GINO; Tang, W.; Taylor, C.; Tkachenko, S.; Vernarsky, B.; Vineyard, M.; Vlassov, A.; Voskanyan, H.; Voutier, E.; Watts, D.; Wood, M.; Zachariou, N.; Zana, L.; Zhao, B.; Zhao, Z.

doi:10.1103/PhysRevD.85.052004

The CLAS detector was used to obtain the first ever measurement of the electromagnetic decay of the Σ*+(1385) from the reaction γp→K0Σ*+(1385). A real photon beam with a maximum energy of 3.8 GeV was incident on a liquid-hydrogen target, resulting in the photoproduction of the kaon and Σ* hyperon. Kinematic fitting was used to separate the reaction channel from the background processes. The fitting algorithm exploited a new method to kinematically fit neutrons in the CLAS detector, leading to the measured decay widths ratio Σ+(1385)→Σ+γ/Σ+(1385)→Σ+π0=11.95±2.21(stat)-1.21+0.53(sys)% and a deduced partial width of 250.0±56.9(stat)-41.2+34.3(sys) keV. A U-spin symmetry test using the SU(3) flavor-multiplet representation yields predictions for the Σ*+(1385)→Σ+γ and Σ*0(1385)→Λγ partial widths that agree with the experimental measurements.