Related papers: Bulk viscosity in kaon condensed matter
The bulk viscosities of two color-superconducting phases, the color-flavor locked (CFL) phase and the 2SC phase, are computed and compared to the result for unpaired quark matter. In the case of the CFL phase, processes involving kaons and…
In nuclear matter in isolated neutron stars, the flavor content (e.g., proton fraction) is subject to weak interactions, establishing flavor ($\beta$-)equilibrium. However, there can be deviations from this equilibrium during the merger of…
We study weak interactions involving Goldstone bosons in the neutral kaon condensed phase of color flavor locked quark matter. We calculate the rates for the dominant processes that contribute to the neutrino mean free p ath and to neutrino…
The history and recent progresses in the study of bulk viscosity in nuclear and quark matter are reviewed. The constraints from baryon number conservation and electric neutrality in quark matter on particle densities and fluid velocity…
The core of neutron-star matter is supposed to be at a much higher density than the normal nuclear matter density for which various possibilities have been suggested such as, for example, meson or hyperon condensation and/or deconfined…
In this work, we propose a meta-modelling technique to nuclear matter on the basis of a relativistic density functional with density-dependent couplings. Identical density dependence for the couplings both in the isoscalar and isovector…
The spin rate \Omega of neutron stars at a given temperature T is constrained by the interplay between gravitational-radiation instabilities and viscous damping. Navier-Stokes theory has been used to calculate the viscous damping timescales…
Kaon polarization operator in dense baryonic matter of arbitrary isotopic composition is calculated including s- and p-wave kaon-baryon interactions. The regular part of the polarization operator is extracted from the realistic kaon-nucleon…
We investigate the effect of neutrino trapping on kaon condensation process and Equation of State (EOS) in a newly formed neutron star which is less than several seconds old. Using nonlinear relativistic mean field model, we find that the…
We confirmed the following idea by numerical calculation: The extended structure of baryons may make the nuclear equation of state stiffer at higher density while keeping the compression modulus for normal nuclear matter around its…
We study the impact of additional couplings in the relativistic mean field (RMF) models, in conjunction with antikaon condensation, on various neutron star properties. We analyze different properties such as in-medium antikaon and nucleon…
We study the structure of protoneutron stars within the finite temperature Brueckner-Bethe-Goldstone many-body theory. If nucleons, hyperons, and leptons are present in the stellar core, we find that neutrino trapping stiffens considerably…
We discuss the bulk viscosity of hot and dense $npe\mu$ matter arising from weak-interaction direct Urca processes. We consider two regimes of interest: (a) the neutrino-transparent regime with $T\leq T_{\rm tr}$ ($T_{\rm tr}\simeq 5\div…
Effects of the neutrino trapping and symmetry energy behavior are investigated in the framework of the chiral Kaplan-Nelson model with kaon condensation. Decrease in the condensation threshold during deleptonization if found to be generic…
For beta-equilibrated nuclear matter we estimate the contribution to the bulk viscosity from purely leptonic processes, namely the conversion of electrons to and from muons. For oscillation frequencies in the kiloHertz range, we find that…
Possible coexistence and/or competition of kaon condensation with hyperons are investigated in hyperonic matter, where hyperons are mixed in the ground state of neutron-star matter. The formulation is based on the effective chiral…
Out-of-equilibrium reactions between different particle species are the main processes contributing to bulk viscosity in neutron stars. In this work, we numerically compare three different approaches to the modeling of bulk viscosity: the…
We study relativistic mean-field models with hadron masses and coupling constants depending self-consistently on a scalar meson field. We demonstrate that by the field redefinition some models can be equivalently transformed into each…
Uncertainty of the hyperon couplings, in particular, that of the $\Sigma^-$, in dense matter raises the question of the behavior of the electrochemical potential in neutron star matter, which is crucial to the possible presence of the kaon…
In this article I will review the theory behind the gravitational wave driven r-mode instability in rapidly rotating neutron stars and discuss which constraints can be derived from observations of spins and temperatures in Low Mass X-ray…