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Density functional theory for nuclear fission -- a proposal

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 نشر من قبل Jacek Dobaczewski
 تاريخ النشر 2019
  مجال البحث
والبحث باللغة English
 تأليف J. Dobaczewski




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The fission process is a fascinating phenomenon in which the atomic nucleus, a compact self-bound mesoscopic system, undergoes a spontaneous or induced quantum transition into two or more fragments. A predictive, accurate and precise description of nuclear fission, rooted in a fundamental quantum many-body theory, is one of the biggest challenges in science. Current approaches assume adiabatic motion of the system with internal degrees of freedom at thermal equilibrium. With parameters adjusted to data, such modelling works well in describing fission lifetimes, fragment mass distributions, or their total kinetic energies. However, are the assumptions valid? For the fission occurring at higher energies and/or shorter times, the process is bound to be non-adiabatic and/or non-thermal. The vision of this project is to go beyond these approximations, and to obtain a unified description of nuclear fission at varying excitation energies. The key elements of this project are the use of nuclear density functional theory with novel, nonlocal density functionals and innovative high-performance computing techniques. Altogether, the project aims at better understanding of nuclear fission, where slow, collective, and semi-classical effects are intertwined with fast, microscopic, quantum evolution.



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