Nuclear Theory·nucl-th

Wednesday·September 7, 2016

9 papers—4 primary·5 cross-listed

01
[Submitted on 5 Sept 2016]
Isospin dependence of nucleon effective masses in neutron-rich matter
Bao-An Li · Bao-Jun Cai · Lie-Wen Chen · Xiao-Hua Li
In this talk, we first briefly review the isospin dependence of the total nucleon effective mass $M_{J}^{*}$ inferred from analyzing nucleon-nucleus scattering data within an isospin dependent non-relativistic optical potential model, and the isospin dependence of the nucleon E-mass $M_{J}^{*, E}$ obtained from applying the Migdal-Luttinger theorem to a phenomenological single-nucleon momentum distribution in nuclei constrained by recent electron-nucleus scattering experiments. Combining information about the isospin dependence of both the nucleon total effective mass and E-mass, we then infer the isospin dependence of nucleon k-mass using the well-known relation $M_{J}^{*} = M_{J}^{*, E} \cdot M_{J}^{*, k}$ . Implications of the results on the nucleon mean free path (MFP) in neutron-rich matter are discussed.
Comments:
An invited talk given at the 5th International Workshop on Nuclear Dynamics in Heavy-Ion Reactions (IWND2016), Xinxiang, China, May 15-20, 2016
Subjects:
Nuclear Theory (nucl-th); Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Experiment (nucl-ex)
arXiv:
1609.01324 [pdf]
Nucl.Sci.Tech.(2016)·10 citations
02
[Submitted on 6 Sept 2016]
3 $α$ -cluster structure and monopole transition in $^{12}$ C and $^{14}$ C
Yuta Yoshida · Yoshiko Kanada-En'yo
3 $α$ -cluster structures and monopole transitions of $0^{+}$ states in $^{12}$ C and $^{14}$ C were investigated with $3 α$ - and $^{10}$ Be+ $α$ -cluster models. A gas-like $3 α$ state and a bending-chain $3 α$ state were obtained in the $0_{2}^{+}$ and $0_{3}^{+}$ states of $^{12}$ C, respectively. In $^{14}$ C, a linear-chain 3 $α$ structure is found in the $0_{4}^{+}$ state near the $^{10}$ Be+ $α$ threshold, but a cluster gas-like state does not appear because valence neutrons attract $α$ clusters and suppress spatial development of 3 $α$ clustering. It was found that the linear-chain state in $^{14}$ C is stabilized against the bending and $α$ escaping modes by valence neutrons. The monopole transition strengths in $^{12}$ C are enhanced by $3 α$ -cluster developing, whereas, those in $^{14}$ C are not enhanced so much because of the tight binding of $α$ clusters by valence neutrons.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1609.01407 [pdf]
1 citation
03
[Submitted on 6 Sept 2016]
Baryon Number Fluctuations in Quasi-particle Model
Ameng Zhao🇨🇳 · Xiaofeng Luo🇨🇳 · Hongshi Zong🇨🇳
Baryon number fluctuations are sensitive to the QCD phase transition and QCD critical point. According to the Feynman rules of finite-temperature field theory, we calculated various order moments and cumulants of the baryon number distributions in the quasi-particle model of quark gluon plasma. Furthermore, we compared our results with the experimental data measured by the STAR experiment at RHIC. It is found that the experimental data can be well described by the model for the colliding energies above 30 GeV and show large discrepancies at low energies. It can put new constraint on qQGP model and also provide a baseline for the QCD critical point search in heavy-ion collisions at low energies.
Comments:
13 pages, 5 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1609.01416 [pdf]
EPJC(2017)·6 citations
04
[Submitted on 6 Sept 2016]
Microscopic phase-space exploration modeling of $^{258}$ Fm spontaneous fission
Yusuke Tanimura🇫🇷 · Denis Lacroix🇫🇷 · Sakir Ayik🇺🇸
We show that the total kinetic energy (TKE) of nuclei after the spontaneous fission of $^{258}$ Fm can be well reproduced using simple assumptions on the quantum collective phase-space explored by the nucleus after passing the fission barrier. Assuming energy conservation and phase-space exploration according to the stochastic mean-field approach, a set of initial densities is generated. Each density is then evolved in time using the nuclear time-dependent density-functional theory. This approach goes beyond mean-field by allowing spontaneous symmetry breaking as well as a wider dynamical phase-space exploration leading to larger fluctuations in collective space. The total kinetic energy and mass distributions are calculated. New information on the fission process: fluctuations in scission time, strong correlation between TKE and collective deformation of daughter nuclei as well as pre- and post-scission particle emission, are obtained.
Comments:
Accepted to PRL (Supplement material available upon demand). All calculations made with dynamical pairing
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
1609.01424 [pdf]
PRL(2017)·102 citations

Affiliations

first authorsco-authorsvia INSPIRE

Isospin dependence of nucleon effective masses in neutron-rich matter

3α-cluster structure and monopole transition in 12C and 14C

Baryon Number Fluctuations in Quasi-particle Model

Microscopic phase-space exploration modeling of 258Fm spontaneous fission

Affiliations

3 $α$ -cluster structure and monopole transition in $^{12}$ C and $^{14}$ C

Microscopic phase-space exploration modeling of $^{258}$ Fm spontaneous fission