η nuclear interaction: Optical model versus coupledchannels approach
Abstract
The existence of possible η nuclear bound states is closely related to the corresponding scattering lengths. While the sign of its real part may indicate a bound state, a large (always positive) imaginary part can prevent such a state. Most theoretical calculations for, e.g., ^{3}He predict quite sizable imaginary parts with no bound state. It is shown that a generalization of the conventional phenomenological optical model potential to coupled channels, based otherwise on the same assumptions but treating the pionic channel explicitly, can yield much smaller inelasticity still starting with elementary η N interactions giving the same η N scattering lengths. As representative examples this decrease is argued by model calculations in the cases of η ^{3}He and η ^{12}C.
 Publication:

Physical Review C
 Pub Date:
 November 2015
 DOI:
 10.1103/PhysRevC.92.055205
 arXiv:
 arXiv:1502.03278
 Bibcode:
 2015PhRvC..92e5205N
 Keywords:

 25.80.e;
 21.85.+d;
 13.75.n;
 24.10.Ht;
 Meson and hyperoninduced reactions;
 Mesic nuclei;
 Hadroninduced low and intermediateenergy reactions and scattering;
 Optical and diffraction models;
 Nuclear Theory;
 High Energy Physics  Phenomenology
 EPrint:
 15 pages, 4 figures, verbal clarifications added, Conclusion extended