Microscopic self-consistent description of induced fission dynamics: Finite-temperature effects

Znanstveni rad - Izvorni znanstveni rad

• Autor: Jie Zhao
• Autor: Tamara Nikšić; MBZ: 234533
• Autor: Dario Vretenar; MBZ: 9570
• Autor: Shan-Gui Zhou
• Autorova ustanova: Sveučilište u Zagrebu; Prirodoslovno-matematički fakultet; (Fizički odsjek)
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Fizika

Sažetak (engleski)

The dynamics of induced fission of 226Th is investigated in a theoretical framework based on the finite-temperature time-dependent generator coordinate method (TDGCM) in the Gaussian overlap approximation (GOA). The thermodynamical collective potential and inertia tensor at temperatures in the interval T=0–1.25 MeV are calculated using the self-consistent multidimensionally constrained relativistic mean-field (MDC-RMF) model, based on the energy density functional DD-PC1. Pairing correlations are treated in the BCS approximation with a separable pairing force of finite range. Constrained RMF+BCS calculations are carried out in the collective space of axially symmetric quadrupole and octupole deformations for the asymmetric fissioning nucleus 226Th. The collective Hamiltonian is determined by the temperature-dependent free energy surface and perturbative cranking inertia tensor, and the TDGCM+GOA is used to propagate the initial collective state in time. The resulting charge and mass fragment distributions are analyzed as functions of the internal excitation energy. The model can qualitatively reproduce the empirical triple-humped structure of the fission charge and mass distributions already at T=0, but the precise experimental position of the asymmetric peaks and the symmetric-fission yield can only be accurately reproduced when the potential and inertia tensor of the collective Hamiltonian are determined at finite temperature, in this particular case between T=0.75 MeV and T=1 MeV.

• Ključne riječi (engleski): induced fission; nuclear energy density functional; finite temperature
• 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. 99, br. 1, 014618
• p-ISSN: 2469-9985
• DOI: https://doi.org/10.1103/physrevc.99.014618
• URN:NBN: urn:nbn:hr:217:297554
• Datum objave publikacije: 2019
• URL dokumenta: https://journals.aps.org/prc/abstract/10.1103/PhysRevC.99.014618
• Vrsta resursa: Tekst
• Prava pristupa: Otvoreni pristup
• Javna napomena: © 2019 American Physical Society. Received 16 September 2018. Published 22 January 2019.
• Datum i vrijeme pohrane: 2020-03-01 19:25:23