Gaussian Source One-Boson-Exchange Potential between Two Octet Baryons

Abstract

The nonstatic baryon-baryon potential arising from the Gaussian meson source function, G i exp (- 2 i r 2 /4), is constructed by exchanging the scalar, pseudoscalar and vector meson nonets, where G i is the strength and A i the size parameter of source i (i = 1,2). This potential is referred to as GSOBEP. It has no singularity at the origin. In this potential, the radial function behaves like the Yukawa function in the outer region (r > 1 fm), and like the Yukawa function multiplied by the error function in the inner region (r < 1 fm). The Gaussian source is assumed to originate from the statistical distribution of valence quarks and many sea quarks. The potential parameters consist of the SU(3) parameters, such as the singlet and octet coupling constants, g 1 and g 8 , the coupling ratio α = g F /(g D + g F ), the singlet-octet mixing angle 0 for each meson, and the effective source size parameter, expressed as Λ = Λ 1 Λ 2 /√Λ 2 1 + Λ 2 2 . The potential parameters are determined by the X 2 -fitting to the nucleon-nucleon, hyperon-nucleon and hyperon-hyperon data. The fit is quite good on the whole.