TABLE VII: Lorentzian-fit parameters of ISGQR strength distributions in the Sn isotopes, as extracted from MDA. The results from TAMU work, where available, are provided for compari- son [19, 21]. a Only statistical uncertainties are included; systematic errors, mostly from DWBA calculations, are ∼ 20%. that are significantly closer to the experimental values, in particular with the surface pairing forces and the SKM* interaction ( K$_{∞}$ ∼ 215 MeV) [78]. Thus, while pairing effects lower the ISGMR excitation energies, one still needs to reduce the K$_{∞}$ value by ∼ 10% for achieving a reasonable agreement with the experimental data. A very intriguing possibility in explaining the “softness” of the Sn isotopes has been offered very recently by Khan [79, 80]. The author asserts that, in analogy with the mutually-enhanced-magicity (MEM) effect observed in predictions of masses with different energy-density functionals [81, 82], the ISGMR energy in the doubly-magic nuclei might be anomalously higher. The obvious implication is that the calculations using interactions that are successful in describing the ISGMR in the doubly-magic nucleus $^{208}$Pb would necessarily overestimate the ISGMR energies in the open-shell nuclei. If this effect is manifested in any significant way, the energy of the ISGMR in the non-doubly-magic Pb isotopes, $^{204}$Pb and $^{206}$Pb, would be measurably lower than that in $^{208}$Pb [80]. In the only measurement of the ISGMR in $^{206}$Pb reported so far [83], this conjecture does not appear to hold. Still, precise 21 Target E$_{ISGQR}$ (MeV) Γ (MeV) EWSR a Reference $^{112}$Sn 13 . 4 ± 0 . 1 7 . 0 ± 0 . 5 1 . 08 ± 0 . 04 This work 13 . 48 +0 . 15 − 0 14 4 . 90 +0 . 22 − 0 27 0 . 88 +0 . 14 − 0 13 TAMU $^{114}$Sn 13 . 2 ± 0 . 1 6 . 8 ± 0 . 4 1 . 25 ± 0 . 05 This work $^{116}$Sn 13 . 1 ± 0 . 1 6 . 4 ± 0 . 4 1 . 12 ± 0 . 04 This work 13 . 50 ± 0 . 35 5 . 00 ± 0 . 30 1 . 08 ± 0 . 12 TAMU $^{118}$Sn 13 . 1 ± 0 . 1 6 . 6 ± 0 . 3 1 . 08 ± 0 . 03 This work $^{120}$Sn 12 . 9 ± 0 . 1 7 . 0 ± 0 . 7 1 . 04 ± 0 . 04 This work $^{122}$Sn 12 . 8 ± 0 . 1 7 . 8 ± 0 . 6 1 . 25 ± 0 . 04 This work $^{124}$Sn 12 . 6 ± 0 . 1 7 . 7 ± 0 . 9 1 . 13 ± 0 . 04 This work 12 . 72 +0 . 11 − 0 11 4 . 20 +0 . 32 − 0 03 0 . 89 +0 . 15 − 0 10 TAMU