arXiv subjects

P S Shternin

Publications and source records attributed to P S Shternin.

2 recordsLinked to original sources

arXiv2021

Transport coefficients in neutron star cores in BHF approach. Comparison of different nucleon potentials

Thermal conductivity and shear viscosity of npe$μ$ matter in non-superfluid neutron star cores are considered in the framework of Brueckner-Hartree-Fock many-body theory. We extend our previous work (Shternin, Baldo and Haensel, 2013) by analysing different nucleon-nucleon potentials and different three-body forces. We find that the use of different potentials leads up to one order of magnitude variations in the values of the nucleon contribution to transport coefficients. The nucleon contribution dominates the thermal conductivity, but for all considered models the shear viscosity is dominated by leptons.

nucl-th↗

arXiv2018

Estimation of the temperature-density relation in the intergalactic medium at $\mathbf{z\sim 2-4}$ via Ly$\mathbfα$ forest

Quasar spectra provide a unique opportunity to investigate the intergalactic medium at high redshifts. The spectral analysis of the Ly$α$ forest allows us to constrain the effective equation of state of the intergalactic medium and its changes during the evolution of the Universe. Based on the Voigt profile fitting of Ly$α$ forest lines in 50 high-resolution QSO spectra obtained at Keck telescope we present new measurements of the power-law index $γ$ of temperature-density relation in IGM for six redshift bins in the range $z=1.6-3.7$. We find that the IGM state is close to isothermal ($γ\approx 1$) at $z\sim 3$ which may indicate that HeII reionization occurred at this redshift.

astro-ph.CO↗