Asymmetric behavior of the B$(E2 \uparrow; 0^+ \rightarrow 2^+)$ values in $^{104-130}$Sn and Generalized Seniority

TL;DR

This paper evaluates B(E2) transition values in Sn isotopes, revealing asymmetric behavior and a dip near mid-shell, explained through generalized seniority, aiding shell model calculations.

Contribution

It introduces a generalized seniority approach to explain B(E2) asymmetries and guides valence space selection for shell model calculations.

Findings

Confirmed asymmetric B(E2) behavior in Sn isotopes.

Explained the dip near $^{116}$Sn with orbital changes.

Shell model calculations aligned with experimental data.

Abstract

We present freshly evaluated B$(E2\uparrow;0^+\rightarrow2^+)$ values across the even-even Sn-isotopes which confirm the presence of an asymmetric behavior as well as a dip in the middle of the full valence space. We explain these features by using the concept of generalized seniority. The dip in the B$(E2)$ values near $^{116}$Sn is understood in terms of a change in the dominant orbits before and after the mid shell, which also explains the presence of asymmetric peaks in the B$(E2)$ values. This approach helps in deciding the most active valence spaces for a given set of isotopes, and single out the most useful truncation scheme for Large Scale Shell Model (LSSM) calculations. The LSSM calculations so guided by generalized seniority are also able to reproduce the experimental data on B$(E2)\uparrow$ values quite well.