PaperPanorama
FAQ

Nuclear Theory·nucl-th

Wednesday·February 12, 2020

8 papers—3 primary·5 cross-listed

All8Primary3Cross-lists5
  1. 01

    Statistical aspects of nuclear mass models

    Vojtech Kejzlar · Léo Neufcourt · Witold Nazarewicz · Paul-Gerhard Reinhard

    We study the information content of nuclear masses from the perspective of global models of nuclear binding energies. To this end, we employ a number of statistical methods and diagnostic tools, including Bayesian calibration, Bayesian model averaging, chi-square correlation analysis, principal component analysis, and empirical coverage probability. Using a Bayesian framework, we investigate the structure of the 4-parameter Liquid Drop Model by considering discrepant mass domains for calibration. We then use the chi-square correlation framework to analyze the 14-parameter Skyrme energy density functional calibrated using homogeneous and heterogeneous datasets. We show that a quite dramatic parameter reduction can be achieved in both cases. The advantage of Bayesian model averaging for improving uncertainty quantification is demonstrated. The statistical approaches used are pedagogically described; in this context this work can serve as a guide for future applications.

    nucl-thstat.APstat.MLJ.Phys.G(2020)·42 citations
  2. 02

    Asymptotic of the electric structure function and the deuteron wave function

    V.I. Zhaba

    The main features of obtaining the asymptotic behaviour of the electric structure function A(p) at large values of the transmitted momentum are analysed. The asymptotic behaviour of the structure function A(p) was determined to take into account the asymptotic behaviour of the deuteron form factors and the original dipole approximation for the nucleon form factors. Asymptotic values of A(p) were obtained for the nucleon-nucleon potential Reid93 and compared with the calculations for different nucleon form factors models and their approximations. In the broad momentum range up to 12.5 fm^(-1), the basic forms of the asymptotic behaviour of the electric structure function are demonstrated and compared with the experimental data of the modern collaborations. As the analysis shows in most cases considered, the asymptotic for A(p) is represented in the form of the power function p^(-n).

    nucl-thMod.Phys.Lett.A(2020)·1 citation
  3. 03

    Quantum expression for the electrical conductivity of massless quark matter and of the hadron resonance gas in the presence of a magnetic field

    Jayanta Dey🇮🇳 · Subhasis Samanta🇵🇱 · Sabyasachi Ghosh🇮🇳 · Sarthak Satapathy🇮🇳

    We have studied the classical and quantum expressions of electrical conductivity and their numerical estimation in the presence of a magnetic field for hadron resonance gas (HRG) and massless quark matter. Classical results of transport coefficients of HRG matter in the presence of a magnetic field were studied previously by Dash et al. [Phys. Rev. D 102, 016016 (2020)] using the standard relaxation time approximation in the Boltzmann equation. In the same reference, the transition from isotropic transport coefficients to anisotropic coefficients in the presence of a magnetic field was also estimated for massless and HRG matter. This led to an upper limit or Stefan-Boltzmann (SB) type limit to the nonperturbative domain transition of transport coefficients. In a similar context, the present work has concentrated on the classical to quantum transition of HRG transport from the domain of high temperature and low magnetic field to that of low temperature and high magnetic field. We have also compared the quantum modification of HRG results with that of massless quark matter, where we observed an opposite trend. A similar kind of quantum effect is also noticed between mesons and baryons due to their different particle distribution functions. Despite the fact that HRG contains both mesons and baryons, Landau quantization of its net magnetothermodynamic phase space reveals meson- or boson-dominated quantum modification. That is why the quantum modification of HRG results reveals the opposite trend from that of massless quark matter, which faces fermionic quantum modification.

    nucl-thhep-phhep-thPRC(2022)·31 citations

Affiliations

first authorsco-authorsvia INSPIRE