1998/07/31 by Th. A. Rijken, V. G. J. Stoks, Y. Yamamoto +1 · 27 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-th
paper · pdf · doi:10.1103/physrevc.59.21
published as Phys.Rev.C59:21-40,1999 · 37 pages, 4 figures
arxiv created 1998/07/31 · openalex publication_date 1999/01/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
A new Nijmegen soft-core OBE potential model is presented for the low-energy YN interactions. Besides the results for the fit to the scattering data, which largely defines the model, we also present some applications to hypernuclear systems using the G-matrix method. The potentials are generated by the exchange of nonets of pseudoscalar, vector, and scalar mesons. As is standard in the Nijmegen soft-core models, we also include the J=0 contributions from the tensor f2,f2^\ensuremath',a2, and pomeron Regge trajectories, and use Gaussian form factors to guarantee that the potentials have a soft behavior near the origin. An important innovation with respect to the original soft-core potential is the assignment of the cutoff masses for the baryon-baryon-meson (BBM) vertices in accordance with broken SU(3)F, which serves to connect the NN and the YN channels. As a novel feature, we allow for medium strong breaking of the coupling constants, using the 3P0 model with a Gell-Mann--Okubo hypercharge breaking for the BBM coupling. Charge-symmetry breaking in the \ensuremathΛp and \ensuremathΛn channels is included as well. We present six hyperon-nucleon potentials which describe the available YN cross section data equally well, but which exhibit some differences on a more detailed level. The differences are constructed such that the models encompass a range of scattering lengths in the \ensuremathΣN and \ensuremathΛN channels. In all cases, we obtained \ensuremathχ2/Ndata\ensuremath≈0.55 for 35 YN data. In particular, we were able to fit the precise experimental datum rR=0.468\ifmmode±\else\textpm\fi0.010 for the inelastic capture ratio at rest. For the scalar-meson mixing angle we obtained values \ensuremathθS=37\ifmmode^∘\else\textdegree\fi--40\ifmmode^∘\else\textdegree\fi, which points to almost ideal mixing angles for the scalar qq states. The G-matrix results indicate that the remarkably different spin-spin terms of the six potentials appear specifically in the energy spectra of \ensuremathΛ hypernuclei.