Single particle spin orbit strengths of the nucleon and hyperons by SU-6 quark model

Dec, 1999
26 pages
Published in:
  • Nucl.Phys.A 674 (2000) 493-514
e-Print:
Report number:
  • KUNS-1624

Citations per year

2000200620122018202401234
Abstract:
The quark-model hyperon-nucleon interaction suggests an important antisymmetric spin-orbit component. It is generated from a color analogue of the Fermi-Breit interaction dominating in the one-gluon exchange process between quarks. We discuss the strength S_B of the single-particle spin-orbit potential, following the Scheerbaum's prescription. Using the SU6 quark-model baryon-baryon interaction which was recently developed by the Kyoto-Niigata group, we calculate NN, Lambda N and Sigma N G-matrices in symmetric nuclear matter and apply them to estimate the strength S_B. The ratio of S_B to the nucleon strength S_N =~ -40 MeV*fm^5 is (S_Lambda)/(S_N) =~ 1/5 and (S_Sigma)/(S_N) =~ 1/2 in the Born approximation. The G-matrix calculation of the model FSS modifies S_Lambda to (S_Lambda)/(S_N) =~ 1/12. For S_N and S_Sigma, the effect of the short-range correlation is comparatively weak against meson-exchange potentials with a short-range repulsive core. The significant reduction of the Lambda single-particle potential arises from the combined effect of the antisymmetric LS force, the flavor-symmetry breaking originating from the strange to up-down quark-mass difference, as well as the effect of the short-range correlation. The density dependence of S_B is also examined.
  • 13.75.Cs
  • 12.39.Jh
  • 13.75.Ev
  • 24.85.+p
  • YN interaction
  • Quark model
  • G -matrix
  • Hyperon single-particle potential
  • Spin–orbit interaction
  • [formula omitted] interaction
Loading ...