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Nuclear Equilibration Processes at Moderate Excitations

  • M. Blann
Conference paper
Part of the Lecture Notes in Physics book series (LNP, volume 22)

Abstract

The equilibrium statistical model has been with us for over 35 years [52]; direct reaction models have similarly been around for many years. Our intuition and experimental results both tell us that the equilibrium model must become progressively poorer as excitation energy increases, and lifetimes decrease for excited nuclear states. The question becomes one of “what happens on the way to equilibrium?” Does the nucleus decay after achieving an equilibrium state, or before, or a bit of both? What is the time depedence of this process, how does this vary with mass and energy? There have been some models proposed for answering this question in the past, but for the most part, this question involves work dating since 1966. It is therefore a relatively new area in nuclear physics, and one which is still developing. The goal of this presentation is to look at several related models which have been applied to the equilibration question, trying to give a simple qualitative description of the underlying physical assumptions of each model, discussing contrapunctally their similarities and their differences. Comparisons of predictions of the several models with one another will be presented. One must return from the world of fantasy on occasion, and so results of these models will also be compared with experimental results.

Keywords

Fermi Energy Exciton Model Geometry Dependent Hybrid Exciton Number Cascade Calculation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1973

Authors and Affiliations

  • M. Blann
    • 1
  1. 1.Department of Chemistry and Nuclear Structure LaboratoryUniversity of RochesterRochesterUSA

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