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arXiv · 2609.10398

Development of the {\gamma} strength function with the neutron number

Stefan Frauendorf·Ronald Schwengner·Gowhar Bhat·Javid Sheikh
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Abstract

The M1 and E2 {\gamma} strength functions ({\gamma}sf) have been calculated for extended series of the Mo, Fe, Sn, Ge and Gd isotopes using the conventional spherical shell model (SSM) and, as a new tool, the triaxial projected shell model (TPSM). For almost all cases the strong enhancement of the M1 {\gamma}sf (low energy magnetic radiation-LEMAR) is found. In the mid-shell region, a bimodal structure of the LEMAR spike and a bump around 3 MeV, interpreted as the scissors resonance (SR), develops. The combination of LEMAR and the SR is generated by the splitting of the spherical single particle multiplets of given j caused by deformation and their fragmentation over nearby quasiparticle configurations.

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Stefan Frauendorf, Ronald Schwengner, Gowhar Bhat, Javid Sheikh. 2026-09-09. Development of the {\gamma} strength function with the neutron number. https://arxiv.org/abs/2609.10398

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