Unified analysis of spin isospin responses of nuclei

Abstract

We investigate the Gamow-Teller (GT) response functions at a momentum transfer of $q=0\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{\ensuremath{-}1}$ and the pionic response functions for quasielastic scattering (QES) at $q\ensuremath{\approx}1.7\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{\ensuremath{-}1}$ using the continuum random phase approximation with the $\ensuremath{\pi}+\ensuremath{\rho}+{g}^{'}$ model interaction. The Landau-Migdal (LM) parameters, ${g}_{\mathit{NN}}^{'}$ and ${g}_{N\ensuremath{\Delta}}^{'}$, are estimated by comparing the calculations with recent experimental data. The peak of the GT resonance and the pionic response functions below the QES peak constrain ${g}_{\mathit{NN}}^{'}$, whereas the quenching of the GT total strength and the enhanced pionic strength around the QES peak provide information about ${g}_{N\ensuremath{\Delta}}^{'}$. We obtained ${g}_{\mathit{NN}}^{'}=0.6\ifmmode\pm\else\textpm\fi{}0.1$ and ${g}_{N\ensuremath{\Delta}}^{'}=0.35\ifmmode\pm\else\textpm\fi{}0.16$ at $q=0\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{\ensuremath{-}1}$ and ${g}_{\mathit{NN}}^{'}=0.7\ifmmode\pm\else\textpm\fi{}0.1$ and ${g}_{N\ensuremath{\Delta}}^{'}=0.3\ifmmode\pm\else\textpm\fi{}0.1$ at $q\ensuremath{\approx}1.7\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{\ensuremath{-}1}$. These results indicate that the q dependence of the LM parameters is weak.