Λ-Nucleon Charge-Symmetry-Breaking Interaction. II. Rank-2 Potentials

Authors

E. Sullivan
Kenneth L. Hartt, University of Rhode IslandFollow

Document Type

Article

Date of Original Version

9-1-1971

Abstract

A potential model of the Λ−N interaction containing short-range repulsions is constructed to study charge-symmetry-breaking (CSB). Rank-2 nonlocal central potentials and a rank-1 approximation to them (referred to as UPAA) are required to fit low-energy Λ−p scattering cross sections, the Λ-separation energy (B_Λ) from _ΛH³, and a dimensionless parameter which partially characterizes the CSB part of the binding-energy difference between _ΛH⁴ and _ΛH⁴. In a scan of these data, a class of potentials with acceptable x² fits is found. Repulsions are seen to reduce significantly the lower limits of the singlet and triplet CSB strengths required in the entire data scan, from the CSB found earlier without including repulsions. In particular, for the largest value of B_Λ used, 0.25 MeV, qualitative agreement with Downs's SU₃ model of CSB is attained, in that the Λ−p CSB singlet interaction can be repulsive. This conclusion also holds for the UPAA, with an indication that a short-range weakening of Λ−N attraction has an effect similar to a Λ−N repulsion. Effects of isospin mixing in _ΛH³ are taken into account. The Λ−N potentials resulting from this analysis are seen to vary in a systematic way within the statistical spread of available data.

Citation/Publisher Attribution

Sullivan, E., & Hartt, K. (1971). Λ-Nucleon Charge-Symmetry-Breaking Interaction. II. Rank-2 Potentials. Physical Review D, 4(5), 1366. doi: 10.1103/PhysRevD.4.1366

Available at: http://dx.doi.org/10.1103/PhysRevD.4.1366

Publisher Statement

©1971 The American Physical Society