Related papers: PSR 0943+10: a bare strange star?
New millisecond pulsars (MSPs) in compact binaries provide a good opportunity to search for the most massive neutron stars. Their main-sequence companion stars are often strongly irradiated by the pulsar, displacing the effective center of…
We report the discovery of a remarkable subpulse drift pattern in the relatively less studied wide profile pulsar, B0818-41, using high sensitivity GMRT observations. We find simultaneous occurrence of three drift regions with two different…
We study small-amplitude, nonlinear pulsations of uniformly and differentially rotating neutron stars employing a two-dimensional evolution code for general-relativistic hydrodynamics. Using Fourier transforms at several points inside the…
We report on the X-ray properties of four rotation-powered pulsars with characteristic ages in the range 0.3-5 Myr, derived from the analysis of XMM-Newton archival observations. We found convincing evidence of thermal emission only in the…
We study the pulse morphologies and pulse amplitudes of thermally emitting neutron stars with ultrastrong magnetic fields. The beaming of the radiation emerging from a magnetar was recently shown to be predominantly non-radial, with a small…
The properties of rotating neutron stars are investigated using eight equations of state (EOSs). We also study the relations between various observables corresponding to different angular velocities for all those EOSs. All of these EoSs…
r-mode oscillations have been shown to have a significant potential to constrain the composition of fast spinning neutron stars. Due to their high rotation rates, millisecond pulsars (MSPs) provide a unique platform to constrain the…
Strange stars with low masses are suggested to exist in reality, the origin of which could be via accretion-induced collapse (AIC) of white dwarfs. Such a strange star is likely bare, and would thus spin very fast, even to a period of < 0.1…
A mysterious X-ray-emitting object has been detected moving away from the high-mass gamma-ray binary PSR B1259-63, which contains a non-accreting pulsar and a Be star whose winds collide forming a complex interaction structure. Given the…
Pulsars are rapidly spinning neutron stars, that radiate at the expense of their strong magnetic field and their high surface temperature. Five decades of multi-wavelength observations showed a large variety of physical parameters, such as…
In this paper we study a set of twelve pulsars that previously had not been characterized. Our timing shows that eleven of them are "normal" isolated pulsars, with rotation periods between 0.22 and 2.65 s, characteristic ages between 0.25…
We report on the study of the mass-radius (M-R) relation and the radial oscillations of proto strange stars. For the quark matter we have employed the well known density dependent quark mass model and its very recent modification, the…
PSR B0656+14 is a middle-aged pulsar with a characteristic age $\tau_c=110$ kyr and spin-down power $\dot{E}= 3.8\times 10^{34}$ erg s$^{-1}$. Using Chandra data, we searched for a pulsar wind nebula (PWN) and found evidence of extended…
Recent timing observation constrained the braking index of the X-ray pulsar PSR J1640-4631 to be $n=3.15\pm0.03$, which is the highest value of all pulsars with measured braking indices so far. In this Letter, we investigate whether pulsar…
The gravitational radiation from compact pulsar-like stars depends on the state of dense matter at supranuclear densities, i.e., the nature of pulsar (e.g., either normal neutron stars or quark stars). The solid quark star model is focused…
We derive the bulk viscous damping timescale of hybrid stars, neutron stars with quark matter core. The r-mode instability windows of the stars show that the theoretical results are consistent with the rapid rotation pulsar data, which may…
The maximum mass of a neutron star has important implications across multiple research fields, including astrophysics, nuclear physics and gravitational wave astronomy. Compact binary millisecond pulsars (with orbital periods shorter than…
Dwarf galaxies and globular clusters may contain intermediate mass black holes ($10^{3}$ to $10^{5}$ solar masses) in their cores. Estimates of ~$10^{3}$ neutron stars in the central parsec of the Galaxy and similar numbers in small…
Neutron stars are compact objects rotating at high speed, up to a substantial fraction of the speed of light (up to 20\% for millisecond pulsars) and possessing ultra-strong electromagnetic fields (close to and sometimes above the quantum…
The high-energy sources known as anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) are well explained as magnetars: isolated neutron stars powered by their own magnetic energy. After explaining why it is generally believed…