Dissipative dynamics of interacting quantal degrees of freedom in spherical nuclei

A model of quantal Brownian motion in fermionic reservoirs is applied to study the time evolution of a giant isovector dipole mode in Pb208. The coupled equations of irreversible motion for the excited collective mode and for the nucleon intrinsic degrees of freedom are simultaneously solved and the...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Hernández, Ester Susana, Dorso, Claudio Oscar
Publicado: 1984
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_05562813_v30_n5_p1711_Hernandez
http://hdl.handle.net/20.500.12110/paper_05562813_v30_n5_p1711_Hernandez
Aporte de:
Descripción
Sumario:A model of quantal Brownian motion in fermionic reservoirs is applied to study the time evolution of a giant isovector dipole mode in Pb208. The coupled equations of irreversible motion for the excited collective mode and for the nucleon intrinsic degrees of freedom are simultaneously solved and their energies, entropies, and relative populations are observed over a lengthy time interval. The resonant decay can be seen together with the excitation of the Fermi sea towards a non-Fermi asymptotic distribution. It is found that the effective decay rate is smaller than the downwards transition rate, in contrast to the widespread assumption in microscopic models of resonance damping. Diffusion, as well as dissipation, appears as a feature of mutual equilibration. © 1984 The American Physical Society.