Symmetry breaking of Gamow-Teller and magnetic-dipole transitions and its restoration in calcium isotopes

Znanstveni rad - Izvorni znanstveni rad

• Autor: Tomohiro Oishi
• Autor: Ante Ravlić
• Autor: Nils Paar
• Autorova ustanova: Sveučilište u Zagrebu; Prirodoslovno-matematički fakultet; (Fizički odsjek)
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Fizika

Sažetak (engleski)

Nuclear magnetic-dipole (M1) and Gamow-Teller (GT) transitions provide insight into the spin-isospin properties of atomic nuclei. By considering them as unified spin-isospin transitions, the M1/GT transition strengths and excitation energies are subject to isospin symmetry. The excitation properties associated to the M1/GT symmetry need to be clarified within a consistent theoretical approach. In this work, the relationship between the M1 and GT transitions in Ca isotopes is investigated in a unified framework based on the relativistic energy-density functional (REDF) with point-coupling interactions, using the relativistic quasiparticle random-phase approximation (RQRPA). It is shown that the isovector-pseudovector (IV-PV) residual interaction affects both transitions, and the symmetry of M1 and giant-GT transitions is disrupted by this interaction in closed-shell nuclei. In open-shell Ca isotopes, the proton-neutron pairing in the residual RQRPA interaction also plays a role in GT transitions. Due to the interplay between these interactions, the M1/GT symmetry can be restored especially in the 42Ca nucleus, i.e., the giant-GT strength can become comparable to that of the M1 mode in terms of the unified spin-isospin transitions by adjusting the proton-neutron pairing strength to reproduce the experimental low-lying GT-excitation energies. The mirror symmetry of both M1 and GT transitions is also demonstrated for open-shell mirror partners, 42Ca and 42Ti. Further improvements are required to achieve simultaneous reproduction of M1 and GT transition energies in the REDF framework.

• Ključne riječi (engleski): nuclear magnetic-dipole; Gamow-Teller (GT) transitions
• Jezik: engleski
• Vrsta publikacije: Znanstveni rad - Izvorni znanstveni rad
• Status objave: Objavljen
• Vrsta recenzije: Recenziran - međunarodna recenzija
• Verzija publikacije: Objavljena verzija rada (izdavačev PDF)
• Naslov časopisa: Physical Review C
• Brojčani podaci: vol. 105, br. 6, 064309
• p-ISSN: 2469-9985
• e-ISSN: 2469-9993
• DOI: https://doi.org/10.1103/PhysRevC.105.064309
• URN:NBN: urn:nbn:hr:217:541990
• Datum objave publikacije: 2022
• Projekt: Šifra: TTP-2018-07-3554; Naziv (hrvatski): Exotic Nuclear Structure and Dynamics; Naziv (engleski): Exotic Nuclear Structure and Dynamics; Kratica: ExoNSD; Voditelj: Kosuke Nomura; Pravna nadležnost: Hrvatska; Financijer: HRZZ; Linija financiranja: TTP
• Projekt: Šifra: KK.01.1.1.01.0004; Naziv (engleski): QuantiXLie Center of Excellence; Kratica: QuantiXLie; Voditelj: Hrvoje Buljan, Pavle Pandžić; Pravna nadležnost: eu; Financijer: Croatian Government and European Union; Linija financiranja: European Regional Development Fund - the Competitiveness and Cohesion Operational Programme
• URL dokumenta: https://link.aps.org/doi/10.1103/PhysRevC.105.064309
• Vrsta resursa: Tekst
• Prava pristupa: Otvoreni pristup
• Javna napomena: © 2022 American Physical Society. Received 4 January 2022; Accepted 9 June 2022; Published 23 June 2022.
• Datum i vrijeme pohrane: 2023-08-18 17:23:28