QMPACK

Here we show some examples of fssG2.00, which is a new version of fssG.f contained in the QMPACK1.01 package. With this fssG2.00, one can calculate two-baryon problems in the particle basis, by taking into account the so-called pion Coulomb corrections. This implies the exact treatment of the charged and neutral pion masses, as well as the Coulomb interaction between charged baryons. In the RGM framework of the quark-model baryon-baryon interactions, the Coulomb interaction between two three-quark clusters are exactly calculated from the Coulomb force acting between quarks. The exchange Coulomb kernel is fully calculated. As the result, even the np interaction has the small exchange Coulomb effect in the particle basis, in addition to an appreciable pion mass effect and the effect of the neutron - proton mass difference. The higher order effect of QED, namely, the relativistic effect, the magnetic-magnetic interaction, vacuum polarization effect, etc., are all neglected in the pp interaction and others.

Unfortunately, the pion Coulomb corrections are not the end of the story of the charge independence and symmetry breaking even in the nucleon-nucleon interaction. As is well known, only about half of the charge dependence can be explained by the pion Coulomb corrections. We therefore reduced the flavor-siglet scalar meson coupling constant slightly f^S_1 X 0.9949 for the pp and nn systems, in order to take into account the effects from other sources like the two-pion echange and so on. For more details, see our publication Resonating-Group Study of Baryon-Baryon Interactions for the Complete Baryon Octet: NN Interaction, Phys. Rev. C 65, 014002: 1 - 24 (2002)

List of files (2005.7.17)

NNdif.ps NN differential cross sections and polarization

yndif.ps YN differential cross sections

sigma_tot.ps Sigma N total cross sections

sppol.ps Sigma^+ p differential cross sections and polarization

total.ps NN and YN total cross sections

XNtot.ps XN total cross sections

XNtot.tar.gz tar.gz file

fig_NN.ps comparison of NN observables with experiment

fig_phase_fss2.ps S and P wave phase shifts of fss2

fig_cross_fss2.ps total cross sections of fss2

fig_fss2.tar.gz combined tar.gz file