The $0^+$ strength functions

Figure 1 shows the $0^+$ IS and IV smoothed strength functions for $^{132}{\rm Sn}$ calculated with $100$ Arnoldi iterations compared with the standard RPA results from Ref. [17]. Agreement between the strength functions is excellent. The four panels of Fig. 2 show the convergence of the smoothed strength functions of Fig. 1 as the number of Arnoldi iterations increases. The panels show differences of the strength functions calculated at 20 iteration intervals. The convergence is quite satisfactory after 100-120 iterations.

Figure 1: The $0^+$ strength functions in $^{132}{\rm Sn}$ calculated by using $25$ HO shells and $100$ Arnoldi iterations for the SLy4 functional (solid lines), compared with the standard RPA calculation of Ref. [17] obtained for the SkM* functional (dashed lines).

Figure 2: Convergence of the $^{132}{\rm Sn}$ $0^+$ strength functions of Fig. 1. Solid lines are for the IS and dashed lines are for the IV strength functions. Each panel shows the difference of two strength functions, one with $n$ iterations and the other calculated with $n-20$ iterations.