Analysing power A_y in the reaction p(pol) p --> p p eta close to threshold

Winter, P.; Adam, H. -H.; Bauer, F.; Budzanowski, A.; Czyzykiewicz, R.; Goetz, T.; Grzonka, D.; Jarczyk, L.; Khoukaz, A.; Kilian, K.; Kolf, C.; Kowina, P.; Lang, N.; Lister, T.; Moskal, P.; Oelert, W.; Quentmeier, C.; Rozek, T.; Santo, R.; Schepers, G.; Sefzick, T.; Siemaszko, M.; Smyrski, J.; Steltenkamp, S.; Strzalkowski, A.; Wolke, M.; Wuestner, P.; Zipper, W.

Analysing power A_y in the reaction p(pol) p --> p p eta close to threshold

Authors

Description

Measurements of the eta meson production with a polarised proton beam in the reaction p(pol) p --> p p eta have been carried out at an excess energy of Q = 40 MeV. The dependence of the analysing power A_y on the polar angle theta^*_q of the eta meson in the center of mass system (CMS) has been studied. The data indicate the possibility of an influence of p- and d-waves to the close to threshold eta production.
6 pages, 5 figures, in section 3.1 the formula of vec(p) containing fatal typos was removed, and the values in table were corrected