We have examined consequences of strong tidal encounters between a neutron star and a normal star using SPH as a possible formation mechanism of isolated recycled pulsars in globular clusters. We have made a number of SPH simulations for close encounters between a main-sequence star of mass ranging from 0.2 to 0.7 M⊙ represented by an n=3/2 polytrope and a neutron star represented by a point ma...

Modeling the amplitudes and shapes of the X-ray pulsations observed from hot, rotating neutron stars provides a direct method for measuring neutron-star properties. This technique constitutes an important part of the science case for the forthcoming NICER and proposed LOFT X-ray missions. In this paper, we determine the number of distinct observables that can be derived from pulse profile model...

In a coalescing neutron star-neutron star or neutron star-black hole binary, oscillation modes of the neutron star can be resonantly excited by the companion during the final minutes of the binary inspiral, when the orbital frequency sweeps up from a few Hertz to a few thousand Hertz. The resulting resonant energy transfer between the orbit and the neutron star speeds up or slows down the inspi...

Making use of the possibility that gluon condensate can be formed in neutron star core, we study the vortex pinning force between the crust and the interior of the neutron star. Our estimations indicate an increase in pinning strength with the age of the neutron star. This helps in explaining observed pulsar glitches and removes some difficulties faced by vortex creep model.

The Invited Review on Joint Discussion ”High Energy Transients” on XXIIIrd General Assembly of IAU, Kioto, 1997 is presented. The simulated rates of neutron star + neutron star, neutron star + black hole and black hole + black hole mergings are considered in relation with the problem of GRBursts origin and gravitational waves detection.

Recent discovery of the afterglow emission from short gamma-ray bursts suggests that binary neutron star or black hole-neutron star binary mergers are the likely progenitors of these short bursts. The accretion of neutron star material and its subsequent ejection by the central engine implies a neutron-rich outflow. We consider here a neutron-rich relativistic jet model of short bursts, and inv...

It is pointed out that a cavity supernova explosion of a moving massive star could result in a significant offset of the neutron star birthplace from the centre of the nearly spherical supernova remnant. Therefore: a) the high implied transverse velocities of a number of neutron stars (e.g. PSR B 1757-24, SGR 0526-66, 1E 0820-4247) could be reduced; b) the proper motion vector of the neutron st...

Extracting the unique information on ultradense nuclear matter from the gravitational waves emitted by merging neutron-star binaries requires robust theoretical models of the signal. We develop a novel effective-one-body waveform model that includes, for the first time, dynamic (instead of only adiabatic) tides of the neutron star as well as the merger signal for neutron-star-black-hole binarie...

We construct quasiequilibrium sequences of black hole-neutron star binaries for arbitrary mass ratios by solving the constraint equations of general relativity in the conformal thin-sandwich decomposition. We model the neutron star as a stationary polytrope satisfying the relativistic equations of hydrodynamics, and account for the black hole by imposing equilibrium boundary conditions on the s...

We discuss the recent efforts to use a sub-class of neutron-star X-ray transients (the quasi-persistent transients) to probe the properties of neutron-star crusts and cores. Quasi-persistent X-ray transients experience accretion episodes lasting years to decades, instead of the usual weeks to months of ordinary, shortduration transients. These prolonged accretion episodes should significantly h...