Thermal properties of nuclei: The implications of Levinson's theorem

Abstract

Using only the close connection between the bound-state properties of a potential and its scattering phase shifts, a limiting excitation energy of a finite nucleus is predicted. Calculations for Z~ give its value as 8.2MeV/A. The excitation-energy dependence of the level-density parameter is also discussed and the connection with astrophysical calculations of stellar collapse rates is indicated.

Relativistic Thomas-Fermi calculations of hot nuclei

“…On the other hand Fig.6 indicates, that the approach used by de Lima Medeiros and Randrup [18] is able to deliver a decreasing level density with increasing temperature. A similar behaviour was found by Dean and Mosel [39] who used again a different way to treat the continuum contributions. But we want to stress again, that in this high temperature region the physical picture of a hot static equilibrated nucleus becomes in general more and more unrealistic .…”

Characteristics of the fragments produced in central collisions of129Xe+natSnfrom 32Ato 50AMeV

“…This charged product detector covers about 90% of the 4π solid angle. The total number of detection cells is 336 arranged according to 17 16 O beam on a thick C target. These particles were then momentum selected by the "alpha magnetic spectrometer" of GANIL and scattered in a C or Ta target installed in the INDRA reaction chamber.…”

“…Finally, the Statistical Multifragmentation Model (SMM) [14] and the microcanonical multifragmentation model of [15,16] allow primary fragments to be excited, the actual value in any given calculation being determined by energy conservation and the statistical weight given by the associated level density parametrisation. This latter may or may not take into account the level density limitation in isolated nuclei at high excitation [17], equivalent to excluding from the primary partitions levels with very short lifetimes or introducing an effective limiting (maximum) temperature for hot nuclei [18,19].…”

Neutron emission for the fusion ofAr40+Ni,MoYoshida1, Kasagi2, Hama3 et al. 1992Phys. Rev. C214140View full textAdd to dashboardCite

“…Bonche et at. [9] [11] showed that a must decrease with increasing excitation energy because of the finiteness of single-particle space of nucleus. They predicted that a varies from A /13 to A /17 for E, /A =2-5 MeV.…”