14 research outputs found
Evidence for a backward peak in the gamma+d->pi^0+d cross section near the eta threshold
High-quality cross sections for the reaction gamma+d->pi^0+d have been
measured using the CLAS at Jefferson Lab over a wide energy range near and
above the eta-meson photoproduction threshold. At backward c.m. angles for the
outgoing pions, we observe a resonance-like structure near E_gamma=700 MeV. Our
model analysis shows that it can be explained by eta excitation in the
intermediate state. The effect is the result of the contribution of the
N(1535)S_11 resonance to the amplitudes of the subprocesses occurring between
the two nucleons and of a two-step process in which the excitation of an
intermediate eta meson dominates.Comment: slightly modified title, additional paragraph and a table (Table 2)
added on p. 5; to be submitted to EPJA, 6 pages, 3 figure