相关论文: Superradiant amplification by rotating viscous com…
Neutron stars in binary orbit emit gravitational waves and spiral slowly together. During this inspiral, they are expected to have very little vorticity. It is in fact a good approximation to treat the system as having zero vorticity, i.e.,…
We investigate the dynamical behavior of strange quark matter (SQM) objects, such as stars and planets, when subjected to radial oscillations induced by tidal interactions in stellar systems. Our study demonstrates that SQM objects can…
Targets for ground-based gravitational wave interferometers include continuous, quasiperiodic sources of gravitational radiation, such as isolated, spinning neutron stars. In this work we perform evolution simulations of uniformly rotating,…
The post-bounce oscillations of newly-born relativistic stars are expected to lead to gravitational-wave emission through the excitation of nonradial oscillation modes. At the same time, the star is oscillating in its radial modes, with a…
We present the generalization of a recently introduced modified gravitational potential for self-gravitating fluids. The use of this potential allows for an accurate approximation of general relativistic effects in an otherwise Newtonian…
The oscillation modes of stars play an important role in observations, and on the understanding of stellar stability properties. The role of viscosity in the oscillation modes of compact stars has been so far understood very loosely only,…
We consider the spin evolution of highly magnetized neutron stars in a hypercritical inflow just after their birth in supernovae. Presence of a strong magnetic field could deform the star and if the symmetry axis of the field is misaligned…
Accreting neutron stars and black holes share a number of rapid variability characteristics, such as quasi-periodic oscillations and broad-band noise. The frequencies of these features were recently shown to be comparable to fundamental…
I derive a system of pulsation equations for compact stars made up of an arbitrary number of perfect fluids that can be used to study radial oscillations and stability with respect to small perturbations. I assume spherical symmetry and…
The present study of the two-stream instability in stellar disks with counter-rotating components of stars and/or gas is stimulated by recently discovered counter-rotating spiral and S0 galaxies. Strong linear two-stream instability of…
We consider the perturbations of a relativistic star as an initial-value problem. Having discussed the formulation of the problem (the perturbation equations and the appropriate boundary conditions at the centre and the surface of the star)…
The turbulent viscosity of convection is believed to circularize the orbits of close binary stars. When the tidal period is shorter than the turnover time of the largest eddies, turbulent viscosity is believed to be suppressed. The degree…
We investigate the viscosity driven instability in rotating relativistic stars by means of an iterative approach. We focus on polytropic rotating equilibrium stars and impose an m=2 perturbationin the lapse. We vary both the stiffness of…
In the modern era of abundant X-ray detections and the increasing momentum of gravitational waves astronomy, tests of General Relativity in strong field regime become increasingly feasible and their importance for probing gravity cannot be…
Convection in the cores of massive stars becomes anisotropic when they rotate. This anisotropy leads to a misalignment of the thermal gradient and the thermal flux, which in turn results in baroclinicity and circulation currents in the…
The excitation of the axial quasi-normal modes of a relativistic star by scattered particles is studied by evolving the time dependent perturbation equations. This work is the first step towards the understanding of more complicated…
Employing a simplified version of the Israel-Stewart formalism of general-relativistic shear-viscous hydrodynamics, we explore the evolution of a remnant massive neutron star of binary neutron star merger and pay special attention to the…
Oscillation modes of neutron stars, a key target for third-generation gravitational wave detectors, encode key information about their constituent nuclear matter. In this work, we study the effect of viscosity on oscillations of cold,…
In this paper, we provide a simple and modern discussion of rotational superradiance based on quantum field theory. We work with an effective theory valid at scales much larger than the size of the spinning object responsible for…
Viscous fluids can dissipate and alter the propagation of gravitational waves, as well as modify the relaxation and stability properties of self-gravitating fluids. This is particularly relevant in order to understand the relaxation to…