TY  - JOUR
AU  - Haidenbauer, Johann
AU  - Meißner, Ulf-G.
TI  - On the structure in the ΛN cross section at the ΣN threshold
JO  - Chinese physics / C
VL  - 45
IS  - 9
SN  - 2058-6132
CY  - Bristol [u.a.]
PB  - IOP Publ.
M1  - FZJ-2021-03674
SP  - 094104 -
PY  - 2021
AB  - The complexity of threshold phenomena is exemplified on a prominent and long-known case - the structure in the $\Lambda p$ cross section (invariant mass spectrum) at the opening of the $\Sigma N$ channel. The mass splitting between the $\Sigma$ baryons together with the angular momentum coupling in the $^3S_1$- $^3D_1$ partial wave imply that, in principle, up to six channels are involved. Utilizing hyperon-nucleon potentials that provide an excellent description of the available low-energy $\Lambda p$ and $\Sigma N$ scattering data, the shape of the resulting $\Lambda p$ cross section is discussed and the poles near the $\Sigma N$ threshold are determined. Evidence for a strangeness $S=-1$ dibaryon is provided, in the form of a (unstable) $\Sigma N$ bound state in the vicinity of the $\Sigma N$ threshold. Predictions for level shifts and widths of $\Sigma^-p$ atomic states are given.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000692007400001
DO  - DOI:10.1088/1674-1137/ac0e89
UR  - https://juser.fz-juelich.de/record/897208
ER  -