Nuclear Theory·nucl-th

Thursday·October 5, 2023

6 papers—3 primary·3 cross-listed

01
Modeling of nuclear reactions with Langevin calculations
S. Amano · Y. Aritomo · Y. Miyamoto · S. Ishizaki · M. Okubayashi
The mass angle distribution shows a strong correlation between mass and angle when quasifission events are dominant. Therefore, as long as quasifission events are dominant, the mass angle distribution is characterized in that a diagonal correlation appears. This diagonal correlation could not be reproduced in our previous model that is before introducing $f_{ina}$ and $γ_{t}^{0}$ model parameters. In this study, we clarify the indeterminate parameters included in the model to reproduce the diagonal correlation appearing in the mass angle distribution in the $^{48}$ Ti + $^{186}$ W reaction system. As a result, $f_{ina}$ and $γ_{t}^{0}$ of model parameters were found to be key parameters for MAD. it was also found that the balance between $f_{ina}$ and $γ_{t}^{0}$ parameter values is important for the strong correlation between mass and angle.
nucl-thBull.Russ.Acad.Sci.Phys.(2020)·1 citation
02
Ternary quasifission in collisions of actinide nuclei
D. D. Zhang · B. Li · D. Vretenar · T. Nikšić · Z. X. Ren · P. W. Zhao · J. Meng
The microscopic framework of time-dependent covariant density functional theory is applied to a systematic study of ternary quasifission in collisions of pairs of $^{238}$ U nuclei. It is shown that the inclusion of octupole degree of freedom in the case of head-to-head collisions, extends the energy window in which ternary quasifission occurs, and greatly enhances the number of nucleons contained in a middle fragment. Dynamical pairing correlations, included here in the time-dependent BCS approximation, prevent the occurrence of ternary quasifission in head-to-head collisions, and have an effect on the location of the energy window in which a middle fragment is formed in tail-to-tail collisions. In the latter case, as well as for tail-to-side collisions, the formation of very heavy neutron-rich systems in certain energy intervals is predicted.
nucl-thPRC(2024)·19 citations
03
Coupling strength induced BCS-BEC crossover on phase boundary of pion superfluid
Zhiyang Liu🇨🇳 · Shijun Mao🇨🇳
Coupling strength effect on the quark matter with finite isospin chemical potential is studied in a Pauli-Villars regularized NJL model. A BCS-BEC crossover occurs along the phase boundary of pion superfluid phase transition, as increasing coupling strength $G$ . For strong coupling cases, the critical isospin chemical potential for pion superfluid phase transition $μ_{I}^{c}$ is exactly the same as pion mass in vacuum $M_{π}$ . Around the critical point $μ_{I}^{c}$ , the pion superfluid quark matter is in BEC state, associated with a fast increase of pion condensate. For weak coupling cases, we obtain $μ_{I}^{c} < M_{π}$ , and a mass jump of the Goldstone boson at the critical point $μ_{I}^{c}$ . The pion superfluid quark matter is in BCS state even around $μ_{I}^{c}$ , accompanied by a slow increase of pion condensate. Note that $μ_{I}^{c}$ is a non-monotonic function of coupling strength $G$ . On the other hand, coupling strength effect changes the bulk properties of quark matter. In strong (weak) coupling cases, the EoS of quark matter at finite isospin chemical potential is stiff (soft). Therefore, the compact stars composed of strong (weak) coupling pion superfluid quark matter has a heavier (lighter) mass and larger (smaller) radius.
nucl-th0 citations

Affiliations

first authorsco-authorsvia INSPIRE

Modeling of nuclear reactions with Langevin calculations

Ternary quasifission in collisions of actinide nuclei

Coupling strength induced BCS-BEC crossover on phase boundary of pion superfluid

Affiliations