Beam–target helicity asymmetry E in K+Σ− photoproduction on the neutron

• Published in: Physics letters. B Vol. 808; no. C; p. 135662
• Main Authors: Zachariou, N., Watts, D.P., Fleming, J., D'Angelo, A., Bashkanov, M., Hanretty, C., Kageya, T., Klein, F.J., Sandorfi, A., Zonta, I., Adhikari, K.P., Adhikari, S., Amaryan, M.J., Angelini, G., Asryan, G., Atac, H., Barion, L., Bedlinskiy, I., Benmokhtar, F., Biselli, A.S., Boiarinov, S., Briscoe, W.J., Brooks, W.K., Bulumulla, D., Burkert, V., Carman, D.S., Carvajal, J.C., Charles, G., Chetry, T., Ciullo, G., Contalbrigo, M., Dashyan, N., Deur, A., Diehl, S., Dupre, R., Egiyan, H., El Alaoui, A., Fegan, S., Fersch, R., Gavalian, G., Gevorgyan, N., Gilfoyle, G.P., Girod, F.X., Gohn, W., Golovatch, E., Gothe, R.W., Guidal, M., Hafidi, K., Hakobyan, H., Hattawy, M., Heddle, D., Hicks, K., Ho, D., Holtrop, M., Ireland, D.G., Ishkhanov, B.S., Isupov, E.L., Jenkins, D., Jo, H.S., Joosten, S.J., Khachatryan, M., Khandaker, M., Kim, W., Kubarovsky, V., Lanza, L., Leali, M., Lenisa, P., Marchand, D., Marsicano, L., Mascagna, V., Mayer, M., Meziani, Z.E., Mineeva, T., Osipenko, M., Ostrovidov, A.I., Peng, P., Pogorelko, O., Poudel, J., Price, J.W., Prok, Y., Puckett, A.J.R., Raue, B.A., Ripani, M., Rizzo, A., Schumacher, R.A., Shrestha, U., Sokhan, D., Soto, O., Sparveris, N., Strakovsky, I.I., Strauch, S., Tan, J.A., Tyler, N., Venturelli, L., Voskanyan, H., Voutier, E., Walford, N.K., Whisnant, C.S., Wood, M.H., Zhao, Z.W.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 10-09-2020; Elsevier
• Subjects: NUCLEAR PHYSICS AND RADIATION PHYSICS
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2020.135662

We report a measurement of a beam–target double-polarisation observable (E) for the γ→n→(p)→K+Σ−(p) reaction. The data were obtained impinging the circularly-polarised energy-tagged photon beam of Hall B at Jefferson Lab on a longitudinally-polarised frozen-spin hydrogen deuteride (HD) nuclear target. The E observable for an effective neutron target was determined for centre-of-mass energies 1.70≤W≤2.30 GeV, with reaction products detected over a wide angular acceptance by the CLAS spectrometer. These new double-polarisation data give unique constraints on the strange decays of excited neutron states. Inclusion of the new data within the Bonn-Gatchina theoretical model results in significant changes for the extracted photocouplings of a number of established nucleon resonances. Possible improvements in the PWA description of the experimental data with additional “missing” resonance states, including the N(2120)3/2− resonance, are also quantified.