arXiv subjects
Publications and source records attributed to I. Abdurrahman.
We will cover briefly the time-dependent density functional theory approach, extended to include pairing correlations, to induced fission of $^{238}$U(n,f), $^{241,243}$Pu, and $^{238}$Np, and also results on scission neutrons and a number of very nontrivial aspects of induced fission.
While quantum turbulence has been addressed both experimentally (predominantly for superfluid $^4$He and $^3$He) and theoretically, the dynamics of various ensembles of quantized vortices was followed in time only until the vortices decay into phonons. How this ``thermalization'' is achieved is still an unaddressed and thus an unelucidated question. The Unitary Fermi Gas (UFG) is a unique quantum system, which has no classical counterpart and of relevance to neutron stars, cold atoms, condensed matter and nuclear many-body systems. The non-Markovian evolution of an isolated UFG is put in evidence and its entire non-equilibrium evolution can be studied theoretically within a unified theoretical framework. The initial lattice of quantum vortices and anti-vortices evolves through a couple of vortex tangles and excitation of Kelvin waves, where vortices cross and reconnect, until very slowly thermalization sets in.
The intrinsic spins and their correlations are the least understood characteristics of fission fragments from both theoretical and experimental points of view. In many nuclear reactions the emerging fragments are typically excited and acquire an intrinsic excitation energy and an intrinsic spin depending on the type of the reactions and interaction mechanism. Both the intrinsic excitation energies and the fragments intrinsic spins and parities are controlled by the interaction mechanism and conservations laws, which lead to their correlations and determines the character of their de-excitation mechanism. We outline here a framework for the theoretical extraction of the intrinsic spin distributions of the fragments and their correlations within the fully microscopic real-time density functional theory formalism and illustrate it on the example of induced fission of $^{236}$U and $^{240}$Pu, using two nuclear energy density functionals. These fission fragment intrinsic spin distributions display new qualitative features previously not discussed in literature. Within this fully microscopic framework we extract for the first time the intrinsic spin distributions of fission fragments of $^{236}$U and $^{240}$Pu as well as the correlations of their intrinsic spins, which have been debated in literature for more than six decades with no definite conclusions so far.