Quadrupole strength in isobaric triplets

The dependence of the 𝐸⁢2 matrix elements on isospin projection 𝑇_𝑧 is linked to the conservation of the isospin symmetry. To study this conjecture, we calculated the 𝐵⁡(𝐸⁢2 : 2⁺→0⁺) rates for the even-even 𝑇=1 mirror nuclei with 42 ≤ 𝐴 ≤ 98 within nuclear density functional theory, employing the generalized Bohr Hamiltonian, and carrying out angular momentum projection. We demonstrated that collective effects are crucial for describing experimental data near the 𝑁=𝑍 line without invoking explicit beyond-Coulomb isospin symmetry-breaking corrections. We also determined the 𝐵⁡(𝐸⁢2↓) values for odd-odd 𝑇_𝑧=0 nuclei ⁷⁰Br and ⁷⁸Y in doubly blocked configurations. We discussed the requirements for accurately describing isobaric analog states and emphasized how current theoretical results should be interpreted within the study of isospin symmetry across isospin triplets.. Authors: Backes, B. C. [University of York (United Kingdom)] (ORCID:0000000244902802); Dobaczewski, J. [University of York (United Kingdom); Univ. of Warsaw (Poland)] (ORCID:0000000241583770); Muir, D. [University of York (United Kingdom)]; Nazarewicz, W. [Michigan State Univ., East Lansing, MI (United States)] (ORCID:0000000280847425); Reinhard, P.-G. [Univ. of Erlangen-Nuremberg, Erlangen (Germany)] (ORCID:0000000245051552). DOE Contract: SC0013365; SC0021176. Subjects: collective levels; collective models; electromagnetic transitions; nuclear density functional theory; nuclear shapes and moments; nuclear structure & decays