Unified Approach to Nuclear Structure and Reactions, and Nuclear Fission within Time-Dependent Density Functional Theory

par Dr Ibrahim Abdurrahman (FRIB (MSU))

lundi 22 juin 2026, 11:00 → 12:00 Europe/Paris

100/0-A018 - Salle Library (IJCLab)

For many decades, quantum many body methods have been applied successfully in describing the structure of atomic nuclei.  As the models have become more sophisticated, and the available computation resources more powerful, it is now possible to treat nuclear reactions on the same footing. In this work, a framework for modeling nuclear reactions within valence space shell model is presented, focusing on neutron on target reactions, specifically neutron on ²⁰Ne and ³⁶Ar. The framework is general enough to be used with any many body method, provided the method can produce all relevant spectroscopic amplitudes. The framework can also be extended to charge exchange reactions, and to include gamma channels. By treating reactions and structure in a consistent manner, a host of questions can be explored, for example: what is the range  of applicability of Hauser-Feshbach theory, which forms the foundation of compound nuclear reactions. 

 

Among the most difficult reaction channels to treat is nuclear fission. Fission was discovered in 1939 by Hahn and Strassmann, and nearly a century later, it still lacks a completely microscopic description, in part, because it is a highly complex quantum many-body process, with qualitatively distinct stages, each of which occurs at vastly different timescales. In recent times, however, some progress has been made with the advent and advancement of supercomputers, through the use of density functional theory. The second half of this talk will focus specifically on a few select recent results obtained using time-dependent density functional theory to investigate the descend of the compound nucleus from the outer saddle to scission, where the nucleus’ neck ruptures and fission fragments are formed. I will describe some differences between the fission of odd-odd, odd-even, and even-even nuclei, the rupture of the neck and emission of neutrons at scission, and the influence of the outer saddle exit channels on FF observables, such as TKE and excitation energies.

 

Seminar.pdf