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Testing and improvements of gamma-ray strength functions for nuclear model calculations of nuclear data

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 نشر من قبل Vladimir Plujko
 تاريخ النشر 1999
  مجال البحث فيزياء
والبحث باللغة English
 تأليف V.A. Plujko




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A closed-form thermodynamic pole approach,TPA, is developed for average description of the E1 radiative strength functions using the microcanonical ensemble for initial states. A semiclassical description of the collective excitation damping in this method is based on modern physical notion on the relaxation processes in Fermi systems.The TPA model gives rather accurate means of simultaneous description of the gamma- decay and photoabsorption strength functions in the medium and heavy nuclei. It is able to cover a relatively wide energy interval, ranging from zeroth gamma-ray energy to values above GDR peak energy, as compared with the others closed-form models for calculation of the E1 strength.



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