Related papers: Bulk viscosity in neutron stars with hyperon cores
It has been recently argued through numerical work that rotating stars with a high degree of differential rotation are dynamically unstable against bar-mode deformation, even for values of the ratio of rotational kinetic energy to…
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…
We derive the relativistic equations for stellar perturbations, including in a consistent way shear viscosity in the stress-energy tensor, and we numerically integrate our equations in the case of large viscosity. We consider the slow…
The properties of neutron stars are studied in a composite model of the strong interaction. In the regime of low to medium baryonic densities a covariant hadronic model is adopted which includes an exclusive channel for the hyperon-hyperon…
We compute the bulk viscosity of a mixed quark-hadron phase. In the first scenario to be discussed, the mixed phase occurs at large densities and we assume that it is composed of a mixing of hyperonic matter and quarks in the Color Flavor…
Using a realistic equation of state (EOS) of strange quark matter, namely, the modified bag model, and considering the constraints to the parameters of EOS by the observational mass limit of neutron stars, we study the r-mode instability…
In order to extract the precise physical information encoded in the gravitational and electromagnetic signals from powerful neutron-star merger events, we need to include as much of the relevant physics as possible in our numerical…
We consider both mode calculations and time evolutions of axial r-modes for relativistic uniformly rotating non-barotropic neutron stars, using the slow-rotation formalism, in which rotational corrections are considered up to linear order…
We discuss the impact of nuclear reactions on the spectrum of gravity g-modes of a mature neutron star, demonstrating the anticipated disappearance of these modes when the timescale associated with the oscillations is longer than that of…
Motivated by their gravitational-wave driven instability, we investigate the influence of the crust on r-mode oscillations in a neutron star. Using a simplistic model of an elastic neutron star crust with constant shear modulus, we carry…
The hydrodynamics, describing dynamical effects in superfluid neutron stars, essentially differs from the standard one-fluid hydrodynamics. In particular, we have four bulk viscosity coefficients in the theory instead of one. In this paper…
We investigate nuclear reactions and feedback in hyperaccreting neutron star environments, considering accretion rates in the range 0.3 - $3\times10^4$ $M_\odot$ yr$^{-1}$, typical of short-period compact object binaries in common…
We examine bulk viscosity, taking into account trapped neutrinos in baryonic matter, in the context of binary neutron star mergers. Following the merging event, the binary star can yield a remnant compact object with densities up to $5$…
In this work we investigate the influence of neutron stars' crusts on the non-radial $g$-mode oscillations and examine their correlations with nuclear matter properties fixed by adopting 10 different relativistic density functionals. At…
Gravitational radiation tends to drive gravity modes in rotating neutron stars unstable. For an inviscid star, the instability sets in when the rotation frequency is about 0.7 times the corresponding mode frequency of the nonrotating star.…
We study the equation of state of hyperon-rich matter for neutron stars using an extended relativistic mean-field model. We take special care of the recently proposed non-linear behaviour of the vector field which gives a much better…
In this paper, we discuss the damping of density oscillations in dense nuclear matter in the temperature range relevant to neutron star mergers. This damping is due to bulk viscosity arising from the weak interaction ``Urca'' processes of…
We study the impact of nonlinear bulk viscosity due to Urca reactions driven by tidally-induced fluid motion during binary neutron star inspiral. Fluid compression is computed for low radial order oscillation modes through an adiabatic,…
A phase transition occurring in the inner core of a neutron star could be associated to a density discontinuity that would affect the frequency spectrum of the non-radial oscillation modes in two ways. Firstly, it would produce a softening…
We investigate the modal properties of the $r$-modes of rotating neutron stars with the core filled with neutron and proton superfluids, taking account of entrainment effects between the superfluids. The stability of the $r$-modes against…