Nuclear Theory·nucl-th

Thursday·April 4, 2019

11 papers—6 primary·5 cross-listed

01
[Submitted on 3 Apr 2019]
Importance of $α$ -induced reactions and the inverse $(γ, α)$ on $p$ -nuclei
Chirashree Lahiri
We have calculated astrophysical reaction cross-sections for $(γ, α)$ reactions of some nuclei important for the calculation of $p$ -process reaction-decay network. Reaction rates for $α$ -induced reactions are calculated with the semi-microscopic optical potential constructed using double folding method, where nuclear density distributions for finite nuclei along with the effective nucleon-nucleon interaction are the important components of the folded potential. For this purpose density distributions of target nuclei are obtained from relativistic mean field approach. Astrophysical reaction cross section for elastic scattering of $α$ -particle from $^{92}$ Mo target is compared with the existing experimental results to constrain the newly formed potential. Further, to check the credibility of the present theoretical framework, the astrophysical S-factor for ( $α$ , $γ$ ) reactions are compared with the experimental observation, wherever available. Finally, an estimate of dominant photodisintegration channels at various astrophysical temperature is discussed for $p$ -nuclei $^{74}$ Se and $^{96}$ Ru.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1904.01809 [pdf]
Mod.Phys.Lett.A(2019)·0 citations
02
[Submitted on 3 Apr 2019]
Simulating chiral anomalies with spin dynamics
Wen-Hao Zhou🇨🇳 · Jun Xu🇨🇳
Considering that the chiral kinetic equations of motion (CEOM) can be derived from the spin kinetic equations of motion (SEOM) for massless particles with approximations, we simulate the chiral anomalies by using the latter in a box system with the periodic boundary condition under a uniform external magnetic field. We found that the chiral magnetic effect is weaker while the damping of the chiral magnetic wave is stronger from the SEOM compared with that from the CEOM. In addition, effects induced by chiral anomalies from the SEOM are less sensitive to the decay of the magnetic field than from the CEOM due to the spin relaxation process.
Comments:
6 pages, 6 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1904.01834 [pdf]
PLB(2019)·15 citations
03
[Submitted on 3 Apr 2019]
Hydrodynamics with spin --- recent developments
Wojciech Florkowski🇵🇱
Recent theoretical developments in hydrodynamics of particles with spin 1/2 are briefly reviewed.
Comments:
Presented at the Epiphany 2019 Conference, 8-11 January 2019, Krakow, Poland
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1904.01840 [pdf]
Acta Phys.Polon.B(2019)·2 citations
04
[Submitted on 3 Apr 2019]
On the Stability of $Λ (1405)$ Matter
J. Hrtánková🇨🇿 · N. Barnea🇮🇱 · E. Friedman🇮🇱 · A. Gal🇮🇱 · J. Mareš🇨🇿 · M. Schäfer🇨🇿
A hypothesis of absolutely stable strange hadronic matter composed of $Λ (1405)$ baryons, here denoted $Λ^{*}$ , is tested within many-body calculations performed using the Relativistic Mean-Field approach. In our calculations, we employed the $Λ^{*} Λ^{*}$ interaction compatible with the $Λ^{*} Λ^{*}$ binding energy $B_{Λ^{*} Λ^{*}} = 40$ ~MeV given by the phenomenological energy-independent $K ˉ N$ interaction model by Yamazaki and Akaishi (YA). We found that the binding energy per $Λ^{*}$ , as well as the central density in $Λ^{*}$ many-body systems saturates for mass number $A \geq 120$ , leaving $Λ^{*}$ aggregates highly unstable against strong interaction decay. Moreover, we confronted the YA interaction model with kaonic atom data and found that it fails to reproduce the $K^{-}$ single-nucleon absorption fractions at rest from bubble chamber experiments.
Comments:
Proceedings of the HYP2018 conference, Norfolk/Portsmouth, USA, June 24 - 29, 2018, submitted to AIP Conference Proceedings
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1904.01928 [pdf]
AIP Conf.Proc.(2019)·0 citations
05
[Submitted on 3 Apr 2019]
Constraining the Hadron-Quark Phase Transition Chemical Potential via Astronomical Observation
Zhan Bai🇨🇳 · Yu-xin Liu🇨🇳
We investigate the chemical potential and baryon number density of the hadron-quark phase transition in neutron star matter. The hadron matter is described with relativistic mean field theory, and the quark matter is described with the Dyson-Schwinger equation approach of QCD. In order to study the first-order phase transition, we develop the sound speed interpolation scheme to construct the equation of state in the middle density region where the hadron phase and quark phase coexist. The phase transition chemical potential is constrained with the maximum mass, the tidal deformability and the radius of neutrons stars. And the most probable value of the phase transition chemical potential is found.
Comments:
20 pages, 11 figures, 2 tables. Extension of arXiv:1903.12336. Contribution to the Proceedings of the CUSTIPEN Workshop on the EOS of Dense Neutron-Rich Matter in the Era of Gravitational-Wave Astronomy. One Figure, some discussions and References added
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE)
arXiv:
1904.01978 [pdf]
AIP Conf.Proc.(2019)·3 citations
06
[Submitted on 3 Apr 2019]
Implications from GW170817 for $Δ$ -isobar admixed hypernuclear compact stars
Jia Jie Li (ITP, Frankfurt)🇩🇪 · Armen Sedrakian (FIAS)🇩🇪
The effects of $Δ$ isobars on the equation of state of dense matter and structure of compact stars (CSs) are explored within the covariant density functional theory and confronted with the data on tidal deformability (TD) extracted from the GW170817 event. We show that the presence of $Δ$ isobars substantially softens the tension between the predictions of the hypernuclear density functionals and the inference from the observations of relatively small radius and small TD of canonical mass CSs. The TDs deduced from GW170817 are compatible with the existence of hypernuclear CSs containing an admixture of $Δ$ isobars. We thus argue that the GW170817 event is consistent with a merger of a binary CS system having both strangeness (hyperons) and $Δ$ isobars in the stellar core.
Comments:
5 pages, 4 figures, 1 table, matches published version
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1904.02006 [pdf]
ApJL(2019)·89 citations

Affiliations

first authorsco-authorsvia INSPIRE

Importance of α-induced reactions and the inverse (γ,α) on p-nuclei

Simulating chiral anomalies with spin dynamics

Hydrodynamics with spin --- recent developments

On the Stability of Λ(1405) Matter

Constraining the Hadron-Quark Phase Transition Chemical Potential via Astronomical Observation

Implications from GW170817 for Δ-isobar admixed hypernuclear compact stars

Affiliations

Importance of $α$ -induced reactions and the inverse $(γ, α)$ on $p$ -nuclei

On the Stability of $Λ (1405)$ Matter

Implications from GW170817 for $Δ$ -isobar admixed hypernuclear compact stars