Related papers: X-ray Pulsars
Most types of massive stars display X-ray emission that is affected by the properties of their stellar winds. Single non-magnetic OB stars have an X-ray luminosity that scales with their bolometric luminosity and their emission is thought…
A plausible model for the Crab Nebula is one in which a particle dominated, highly relativistic wind from the pulsar passes through a shock front in which the particles attain a power law energy distribution. The electrons and positrons…
The inner region of the accretion disk around a magnetized neutron star is subjected to magnetic torques that induce warping and precession of the disk. These torques arise from interactions between the stellar field and the induced…
The Galactic population of rotation-powered (aka radio) millisecond pulsars (MSPs) exhibits diverse X-ray properties. Energetic MSPs show pulsed non-thermal radiation from their magnetospheres. Eclipsing binary MSPs predominantly have X-ray…
Ultraluminous X-ray sources (ULXs) are extreme X-ray binaries shining above 10^39 erg/s, in most cases as a consequence of super-Eddington accretion onto neutron stars and stellar-mass black holes accreting above their Eddington limit. This…
The spin frequency distribution of accreting millisecond X-ray pulsars cuts off sharply above 730 Hz, well below the breakup spin rate for most neutron star equations of state. I review several different ideas for explaining this cutoff.…
Short-term variability of X-ray continuum spectra has been reported for several Active Galactic Nuclei. Significant X-ray flux variations are observed within time scales down to 10^3-10^5 seconds. We discuss short variability time scales in…
The conventional picture of disk accretion onto magnetized neutron stars has been challenged by the spin changes observed in a few X-ray pulsars, and by theoretical results from numerical simulations of disk-magnetized star interactions.…
The hydrogen and helium accreted by X-ray bursting neutron stars is periodically consumed in runaway thermonuclear reactions that cause the entire surface to glow brightly in X-rays for a few seconds. With models of the emission, the mass…
The giant flares produced by highly magnetized neutron stars, "magnetars," are the brightest sources of high energy radiation outside our solar system. Serendipitous observations with NASA's Rossi X-ray Timing Explorer (RXTE) of the two…
There is growing evidence that some variable high-energy gamma-ray sources are associated with pulsar wind nebulae. We review the current status of X-ray and radio studies of the sources most likely to be significant emitters above 100 MeV.…
We systematically analyze all the available X-ray spectra of disc accreting neutron stars (atolls and millisecond pulsars) from the RXTE database. We show that while these all have similar spectral evolution as a function of mass accretion…
Supergiant High Mass X-ray Binary systems (sgHMXBs) consist of a massive, late type, star and a neutron star. The massive stars exhibits strong, radiatively driven, stellar winds. Wind accretion onto compact object triggers X-ray emission,…
Prompted by the recent discovery of pulsed emission from an ultra-luminous X-ray source, M82 X-2 ("ULX-pulsar"), we perform a two-dimensional radiation-hydrodynamic simulation of a super-critical accretion flow onto a neutron star through a…
Currently, two competing models are invoked in order to explain the observable properties of Anomalous X-ray Pulsars (AXPs). One model assumes that AXP emission is powered by a strongly magnetized neutron star - i.e., a magnetar. Other…
A review of basic properties of Be/X-ray binaries is presented. These systems (called also hard X-ray transients), which form the most numerous class of massive X-ray binaries in the Galaxy, are composed of Be stars and neutron stars (X-ray…
We study the spin evolution of X-ray neutron stars in binary systems, which are being spun up by mass transfer from accretion disks. Our investigation reveals that a quark phase transition resulting from the changing central density induced…
The accreting X-ray pulsar Her X-1 shows two types of long-term variations, both with periods of ~35 days: 1) Turn-on cycles, a modulation of the flux}, with a ten-day long Main-On and a five-day long Short-On, separated by two Off-states,…
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…
Despite considerable evidence verifying that millisecond pulsars are spun up through sustained accretion in low-mass X-ray binaries (LMXBs), it has proven surprisingly difficult to actually detect millisecond X-ray pulsars in LMXBs. There…