Journalartikel
Autorenliste: Witthauer, L.; Dieterle, M.; Afzal, F.; Anisovich, A. V.; Bantes, B.; Bayadilov, D.; Beck, R.; Bichow, M.; Brinkmann, K. -T.; Boese, S.; Challand, Th.; Crede, V.; Dutz, H.; Eberhardt, H.; Elsner, D.; Ewald, R.; Fornet-Ponse, K.; Friedrich, St.; Frommberger, F.; Funke, Ch.; Goertz, St.; Gottschall, M.; Gridnev, A.; Gruener, M.; Gutz, E.; Hammann, D.; Hammann, Ch.; Hannappel, J.; Hartmann, J.; Hillert, W.; Hoffmeister, Ph.; Honisch, Ch.; Jude, T.; Kaiser, D.; Kalinowsky, H.; Kalischewski, F.; Kammer, S.; Kaser, A.; Keshelashvili, I.; Klassen, P.; Kleber, V.; Klein, F.; Koop, K.; Krusche, B.; Lang, M.; Lopatin, I.; Mahlberg, Ph.; Makonyi, K.; Metag, V.; Meyer, W.; Mueller, J.; Muellers, J.; Nanova, M.; Nikonov, V.; Piontek, D.; Reicherz, G.; Rostomyan, T.; Sarantsev, A.; Schmidt, Ch.; Schmieden, H.; Seifen, T.; Sokhoyan, V.; Spieker, K.; Thiel, A.; Thoma, U.; Urban, M.; van Pee, H.; Walford, N. K.; Walther, D.; Wendel, Ch.; Werthmueller, D.; Wilson, A.; Winnebeck, A.
Jahr der Veröffentlichung: 2017
Zeitschrift: The European Physical Journal A
Bandnummer: 53
Heftnummer: 3
ISSN: 1434-6001
eISSN: 1434-601X
DOI Link: https://doi.org/10.1140/epja/i2017-12247-0
Verlag: Springer
Abstract:
Results from measurements of the photoproduction of eta mesons from quasifree protons and neutrons are summarized. The experiments were performed with the CBELSA/TAPS detector at the electron accelerator ELSA in Bonn using the eta -> 3 pi(0) -> 6 gamma decay. A liquid deuterium target was used for the measurement of total cross sections and angular distributions. The results confirm earlier measurements from Bonn and the MAMI facility in Mainz about the existence of a narrow structure in the excitation function of gamma n -> n eta. The current angular distributions show a forward-backward asymmetry, which was previously not seen, but was predicted by model calculations including an additional narrow P-11 state. Furthermore, data obtained with a longitudinally polarized, deuterated butanol target and a circularly polarized photon beam were analyzed to determine the double polarization observable E. Both data sets together were also used to extract the helicity-dependent cross sections sigma(1/2) and sigma(3/2). The narrow structure in the excitation function of gamma n -> n eta appears associated with the helicity-1/2 component of the reaction.
Zitierstile
Harvard-Zitierstil: Witthauer, L., Dieterle, M., Afzal, F., Anisovich, A., Bantes, B., Bayadilov, D., et al. (2017) Photoproduction of η mesons from the neutron: Cross sections and double polarization observable E, The European Physical Journal A, 53(3), Article 58. https://doi.org/10.1140/epja/i2017-12247-0
APA-Zitierstil: Witthauer, L., Dieterle, M., Afzal, F., Anisovich, A., Bantes, B., Bayadilov, D., Beck, R., Bichow, M., Brinkmann, K., Boese, S., Challand, T., Crede, V., Dutz, H., Eberhardt, H., Elsner, D., Ewald, R., Fornet-Ponse, K., Friedrich, S., Frommberger, F., ...Winnebeck, A. (2017). Photoproduction of η mesons from the neutron: Cross sections and double polarization observable E. The European Physical Journal A. 53(3), Article 58. https://doi.org/10.1140/epja/i2017-12247-0
Schlagwörter
BEAM ASYMMETRY; COHERENT PHOTOPRODUCTION; DEUTERON; EXCLUSIVE MEASUREMENT; NEAR-THRESHOLD PHOTOPRODUCTION; NUCLEI; PHOTON; PROTON
