Photoproduction of eta-mesic 3He
Abstract
The photoproduction of eta-mesic 3He has been investigated using the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI. The total inclusive cross section for the reaction gamma+3He->eta+X has been measured for photon energies from threshold to 820 MeV. The total and angular differential coherent eta cross sections have been extracted up to energies of 745 MeV. A resonance-like structure just above the eta production threshold with an isotropic angular distribution suggests the existence of a resonant quasi-bound state. This is supported by studies of a competing decay channel of such a quasi-bound eta-mesic nucleus into pi^0+p+X. A binding energy of (-4.4+-4.2) MeV and a width of (25.6+-6.1) MeV is deduced for the quasi-bound eta-mesic state in 3He.
Keywords
Cite
@article{arxiv.nucl-ex/0312011,
title = {Photoproduction of eta-mesic 3He},
author = {M. Pfeiffer and J. Ahrens and J. R. M. Annand and R. Beck and G. Caselotti and S. Cherepnya and K. Föhl and L. S. Fog and D. Hornidge and S. Janssen and V. Kashevarov and R. Kondratiev and M. Kotulla and B. Krusche and J. C. McGeorge and I. J. D. MacGregor and K. Mengel and J. G. Messchendorp and V. Metag and R. Novotny and M. Rost and S. Sack and R. Sanderson and S. Schadmand and A. Thomas and D. P. Watts},
journal= {arXiv preprint arXiv:nucl-ex/0312011},
year = {2009}
}
Comments
v1: 4 pages, 4 figures, submitted to PRL; v2: minor revisions and corrections, new figure added, 4 pages, 5 figs; v3: minor changes