Related papers: Deciphering Accretion-Driven Starquakes in Recycle…
Recent discoveries by the Rossi X-Ray Timing Explorer indicate that most of the rapidly accreting and weakly magnetic neutron stars in the Galaxy are rotating at spin frequencies greater than 250 Hz. Remarkably, they all rotate in a narrow…
A pulsar, i.e., a spinning neutron star, with a deformation could emit gravitational waves continuously. Such continuous waves, which have not been detected yet, will be very useful to study gravitational physics and to probe the extreme…
Neutron stars are excellent emitters of gravitational waves. Squeezing matter beyond nuclear densities invites exotic physical processes, many of which violently transfer large amounts of mass at relativistic velocities, disrupting…
The detection, in 1998, of the first Accreting Millisecond Pulsar, started an exciting season of continuing discoveries in the fashinating field of compact binary systems harbouring a neutron star. Indeed, in these last three lustres,…
Starquakes probably occur in rapidly spinning or ultra high field neutron stars. In this article, we argue that highly compressed gas containing electron-positron pairs could evaporate and erupt from inside the neutron star when a crack…
Pulsar-like compact stars provide us a unique laboratory to explore properties of dense matter at supra-nuclear densities. One of the models for pulsar-like stars is that they are totally composed of "strangeons", and in this paper we…
The existence of a large number of asymmetric, rotating neutron stars, each individually emitting periodic or quasi-periodic gravitational waves in the frequency band around 100 Hz, raises the possibility of detecting their combined…
Pulsars are stars that emit electromagnetic radiation in well-defined time intervals. The frequency of such pulses decays with time as is quantified by the {\it braking index} ($n$). In the canonical model $n = 3$ for all pulsars, but…
We study the gravitational wave signals emitted from phase-transition induced collapses of rapidly rotating neutron stars to strange stars by performing 3D numerical simulations. Our preliminary results suggest that the complete conversion…
$r$-mode oscillations in rotating neutron stars are a source of continuous gravitational radiation. We investigate the excitation of $r$-modes by the mechanical impact on the neutron star surface of stochastically accreted clumps of matter,…
Spinning neutron stars can emit long-lived gravitational waves. There are several mechanisms that can produce such continuous wave emission. These mechanisms relate to the strains in the elastic crust, the star's magnetic field,…
It has recently been suggested that collapse of neutron stars induced by a phase transition to quark matter can be a considerable source of gravitational waves with kHz frequencies. We demonstrate that if about one percent of all neutron…
Non radial oscillations of neutron stars are associated with the emission of gravitational waves. The characteristic frequencies of these oscillations can be computed using the theory of stellar perturbations, and they are shown to carry…
We examine the time evolution of the frequencies of the gravitational wave after the bounce within the framework of relativistic linear perturbation theory using the results of one dimensional numerical simulations of core-collapse…
The collapse of massive stars not only produces observable outbursts across the entire electromagnetic spectrum but, for Galactic (or near-Galactic) supernovae, detectable signals for ground-based neutrino and gravitational wave detectors.…
The recent direct observation of gravitational wave event $GW170817$ and its $GRB170817A$ signal has opened up a new window to study neutron stars and heralds a new era of Astronomy referred to as the Multimessenger Astronomy. Both…
Many classes of extended scalar-tensor theories predict that dynamical instabilities can take place at high energies, leading to the formation of scalarized neutron stars. Depending on the theory parameters, stars in a scalarized state can…
It is thought that neutron stars in low-mass binary systems can accrete matter and angular momentum from the companion star and be spun-up to millisecond rotational periods. During the accretion stage, the system is called a low-mass X-ray…
Using the Rossi X-ray Timing Explorer (RossiXTE), astronomers have discovered that disk-accreting neutron stars with weak magnetic fields produce three distinct types of high-frequency X-ray oscillations. These oscillations are powered by…
We summarize our current understanding of gravitational wave emission from core-collapse supernovae. We review the established results from multi-dimensional simulations and, wherever possible, provide back-of-the-envelope calculations to…