Nuclear response for the Skyrme effective interaction with zero-range tensor terms

The effects of a zero-range tensor component of the effective interaction on nuclear response functions are determined in the random phase approximation approach. Explicit formulas in the case of symmetric homogeneous isotropic nuclear matter are given for each spin-isospin excitation channel. It is shown for a typical interaction with tensor couplings that the effects are quantitatively important, mainly in vector channels.

Figure 1

Direct and exchange parts of the p-h interaction.

Figure 2

Dynamical structure functions $S^{(\alpha )}(q,\omega )$ calculated for the Skyrme tensor parametrization T44 [17]. The upper, middle, and lower parts, respectively, concern the channels $S=0,S=1$ and $I=0$, and $S=1$ and $I=0$. For each $(S,I,M)$ channel the responses (in M${\mathrm{eV}}^{-1}\hspace{0.5em}{\mathrm{fm}}^{-3}$) are plotted as a function of ω (in MeV). All the responses are calculated for $q=k_F$ at saturation density. Cases (a) and (b) are discussed in the text.