Related papers: Alfv\'en Polar Oscillations of Relativistic Stars
We study the stability of neutron stars with toroidal magnetic fields by magnetohydrodynamic simulation in full general relativity under assumption of axial symmetry. Nonrotating and rigidly rotating neutron stars are prepared for a variety…
We calculate non-axisymmetric oscillations of neutron stars magnetized by purely poloidal magnetic fields. We use polytropes of index $n=1$ and 1.5 as a background model, where we ignore the equilibrium deformation due to the magnetic…
In a strongly magnetized, magnetically dominated relativistic plasma, Alfv\'enic turbulence can extend to scales much smaller than the particle inertial scales. It leads to an energy cascade somewhat analogous to inertial- or…
Stellar pulsations in rotating relativistic stars are reviewed. Slow rotation approximation is applied to solving the Einstein equations. The rotational effects on the non-axisymmetric oscillations are explicitly shown in the polar and…
The effect of Alfv\'en waves on the thermal instability of the Interstellar Medium (ISM) is investigated both analytically and numerically. A stability analysis of a finite amplitude circularly polarized Alfv\'en wave propagating parallel…
The two-component, core-crust, model of a neutron star with homogenous internal and dipolar external magnetic field is studied responding to quake-induced perturbation by substantially nodeless differentially rotational Alfv\'en…
We investigate the instability of purely poloidal magnetic fields in nonrotating neutron stars by means of three-dimensional general-relativistic magnetohydrodynamics simulations, extending the work presented in Ciolfi et al. (2011). Our…
This paper is devoted to the study of the gravitational instability of a medium permeated by a uniform magnetic field along which a circularly polarized Alfven wave propagates. We concentrate on the case of perturbations purely transverse…
We study axisymmetric perturbations of neutron star endowed with a strong magnetic field (magnetars), considering the coupled oscillations of the fluid core with the solid crust. We recover discrete oscillations based mainly in the crust…
Strong magnetic fields in the cores of stars are expected to significantly modify the behavior of gravity waves: this is likely the origin of suppressed dipole modes observed in many red giants. However, a detailed understanding of how such…
Quasinormal modes of ultra compact stars with uniform energy density have been calculated. For less compact stars, there is only one very slowly damped polar mode (corresponding to the Kelvin f-mode) for each spherical harmonic index $l$.…
Non-radial oscillations of neutron stars provide a powerful probe of stellar structure and relativistic gravity, but a fully general relativistic treatment for gravitationally coupled two-fluid stars with independently conserved currents…
An arbitrary initial magnetic field in an A star evolves into a stable equilibrium. Simulations are presented of the formation of non-axisymmetric equilibria consisting of twisted flux tubes meandering under the surface of the star, and…
Alfv\'en waves propagate in electrically conducting fluids in the presence of a magnetic field. Their reflection properties depend on the ratio between the kinematic viscosity and the magnetic diffusivity of the fluid, also known as the…
Alfv\'enic turbulence is an effective mechanism for particle acceleration in strongly magnetized, relativistic plasma. In this study, we investigate a scenario where turbulent plasma is influenced by a strong guide magnetic field, resulting…
We couple internal torsional, magneto-elastic oscillations of highly magnetized neutron stars (magnetars) to their magnetospheres. The corresponding axisymmetric perturbations of the external magnetic field configuration evolve as a…
The problem of relativistic stellar pulsations is studied in a somewhat ad hoc approximation that ignores all fluid motions. This {\em Inverse Cowling Approximation} (ICA) is motivated by two observations: 1) For highly damped ($w$-mode)…
Magnetic fluctuations in the solar wind are often observed to maintain constant magnitude of the magnetic field in a manner consistent with spherically-polarized large-amplitude Alfv\'en waves. We investigate the effect of spherical…
Rotating relativistic stars are receiving significant attention in recent years, because of the information they can yield about the equation of state of matter at extremely high densities and because they are one of the more possible…
Understanding how cool stars produce magnetic fields within their interiors is crucial for predicting the impact of such fields, such as the activity cycle of the Sun. In this respect, studying fully convective stars enables us to…