Microscopic analysis of the low-energy spin scissors resonance

Seminars

Low-Energy Nuclear Physics Seminar

(sectors No.1 and 2 of the scientific department of nuclear theory)

Date and Time: Tuesday, 24 November 2020, at 11:00 AM

Venue: Online conference in Zoom, Bogoliubov Laboratory of Theoretical Physics

Seminar topic: «Microscopic analysis of the low-energy spin scissors resonance»

Authors: V.O. Nesterenko1, P.I. Vishnevskiy1,2,3, J. Kvasil4, W. Kleinig1

1 – Bogoliubov Laboratory of Theoretical Physics, JINR
2 – Dubna State University, Russia
3 – Institute of Nuclear Physic Almaty, Almaty Region, Kazakhstan
4 – Institute of Particle and Nuclear Physics, Charles University, Praha

Speaker: V.O. Nesterenko

Abstract:

The prediction on existence of low-energy spin-scissors resonance (SSR) in deformed nuclei was analyzed within the self-consistent Quasiparticle Random Phase Approximation (QRPA) with Skyrme forces SkM*, SVbas, and SG2. The calculations were performed for deformed nuclei 160,162,164Dy and 232Th proposed earlier as the promising candidates for SSR. The rates of M1 (K=1) transitions and distributions of nuclear currents were analyzed. Our calculations confirm that in strongly deformed nuclei, like 160,162,164Dy, there can exist 1+ spin states located below the conventional orbital scissor resonance. Following our analysis, these states are ordinary spin-flip excitations with a low orbital momentum. So the nuclear deformation is not the primary origin of these states but rather the important factor affecting their properties. This makes questionable the spin-scissors interpretation of the low-energy spin states. QRPA does not confirm the spin character of the low-energy states in less deformed 232Th.