1. Cross section for γn→π0n measured at the Mainz A2 experiment
- Author
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Briscoe, W. J., Hadžimehmedović, M., Kudryavtsev, A. E., Kulikov, V. V., Martemianov, M. A., Strakovsky, I. I., Švarc, Alfred, Tarasov, V. E., Workman, R. L., Abt, S., Achenbach, P., Akondi, C. S., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Annand, J. R. M., Arends, H. J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Bulychjov, S. A., Cividini, F., Collicott, C., Costanza, S., Denig, A., Downie, E. J., Drexler, P., Fegan, S., Ferretti Bondy, M. I., Gardner, S., Ghosal, D., Glazier, D. I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Käser, A., Kashevarov, V. L., Kay, S., Korolija, Milorad, Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., McGeorge, J. C., Middleton, D. G., Miskimen, R., Mornacchi, E., Mushkarenkov, A., Mullen, C., Neganov, A., Neiser, A., Ostrick, M., Otte, P. B., Osmanović, H., Omerović, R., Oussena, B., Paudyal, D., Pedroni, P., Powell, A., Prakhov, S. N., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Sokhoyan, V., Spieker, K., Stahov, J., Steffen, O., Supek, Ivan, Thiel, A., Thiel, M., Thomas, A., Tiator, L., Unverzagt, M., Usov, Yu. A., Walford, N. K., Watts, D. P., Wagner, S., Werthmüller, D., Wettig, J., Wolfes, M., and Zachariou, N.
- Subjects
Physics ,Nuclear Theory ,neutral pion-photoproduction ,tagged photon spectrometer ,microtron ,Nuclear Experiment - Abstract
The gamma n -> pi(0)n differential cross section evaluated for 27 energy bins span the photon-energy range 290-813 MeV (W = 1.195- 1.553 GeV) and the pion c.m. polar production angles, ranging from 18 degrees to 162 degrees, making use of model-dependent nuclear corrections to extract pi(0) production data on the neutron from measurements on the deuteron target. Additionally, the total photoabsorption cross section was measured. The tagged photon beam produced by the 883 MeV electron beam of the Mainz Microtron MAMI was used for the pi(0)-meson production. Our accumulation of 3.6 x 10(6) gamma n -> pi(0)n events allowed a detailed study of the reaction dynamics. Our data are in reasonable agreement with previous A2 measurements and extend them to lower energies. The data are compared with predictions of previous SAID, MAID, and BnGa partial-wave analyses and to the latest SAID fit MA19 that included our data. Selected photon-decay amplitudes N* -> gamma n at the resonance poles are determined for the first time.
- Published
- 2019