| Abstract [eng] |
Low-energy neutron–19Cscattering is studied in the three-body n +n +18Cmodel using a realistic nnpotential and a number of shallow and deep n–18Cpotentials, the latter supporting deeply-bound Pauli-forbidden states that are projected out. Exact Faddeev-type three-body scattering equations for transition operators including two-and three-body forces are solved in the momentum-space partial-wave frame-work. Phase shift, inelasticity parameter, and cross sections are calculated. For the elastic n–19Cscattering in the J=0+partial wave the signatures of the Efimov physics, i.e., the pole in the effective-range ex-pansion and the elastic cross section minimum, are confirmed for both shallow and deep models, but with clear quantitative differences between them, indicating the importance of a proper treatment of deeply-bound Pauli-forbidden states. In contrast, the inelasticity parameter is mostly correlated with the asymptotic normalization coefficient of the 19Cbound state. Finally, in the regime of very weak 19Cbind-ing and near-threshold (bound or virtual) excited 20Cstate the standard Efimovian behaviour of the n–19Cscattering length and cross section was confirmed, resolving the discrepancies between earlier studies by other authors (Mazumdar et al., 2006 [20], Yamashita et al., 2007 [23]). |
