Related papers: Recent Results on the Anomalous X-ray Pulsars
Soft gamma-ray repeaters (SGRs) and Anomalous X-ray pulsars (AXPs) are generally accepted to be magnetars. Recently, Zhang, Xu & Qiao (2000, ApJ, 545, L127) proposed an alternative viewpoint about the nature of the SGRs (and AXPs). In this…
Non pulsating neutron stars in low mass X-ray binaries largely outnumber those that show pulsations. The lack of detectable pulses represents a big open problem for two important reasons. The first is that the structure of the accretion…
Over the last decade, observational evidence has mounted that SGRs/AXPs belong to a particular class of pulsars. Furthermore, fast and very magnetic white dwarfs have been observed, and recently two SGRs with low magnetic fields…
Both neutron stars and strange stars are capable of supporting fast rotations observed in pulsars. On the basis of this it has been argued that some of the pulsars could be strange stars. We investigate whether strange stars can sustain…
We present the first X-ray observations of three recently discovered millisecond pulsars (MSPs) with interesting characteristics: PSR J0337+1715, PSR J0636+5129, and PSR J0645+5158. PSR J0337+1715 is a fast-spinning, bright, and so-far…
We report the first detection of radio emission from any anomalous X-ray pulsar (AXP). Data from the Very Large Array (VLA) MAGPIS survey with angular resolution 6" reveals a point-source of flux density 4.5 +/- 0.5 mJy at 1.4 GHz at the…
It is believed that the radio pulsars rotating at spin periods of about 30 millisecond or even lower got such high spins through the transfer of angular momentum by accreting matter from their binary companions (or past companions) in the…
A catalog of the Galactic population of X-ray pulsars in high-mass X-ray binary (HMXB) systems is presented. It contains information about 82 confirmed sources: 18 persistent and 64 transient pulsars. Their basic parameters include spin…
XMM-Newton archival data for the Small Magellanic Cloud have been examined for the presence of previously undetected X-ray pulsars. One such pulsar, with a period of 202 s, is detected. Its position is consistent with an early B star in the…
The 8.7s X-ray pulsar 4U 0142+61 was monitored by BeppoSAX between January 1997 and February 1998. This source belongs to the rapidly growing class of "anomalous" X-ray pulsars (AXPs) which have pulse periods in the 6-12s range and no…
Axionlike particles (ALPs) are hypothetical light (sub-eV) bosons predicted in some extensions of the Standard Model of particle physics. In astrophysical environments comprising high-energy gamma rays and turbulent magnetic fields, the…
We report the accurate sub-arcsec X-ray position of the new Anomalous X-ray Pulsar (AXP) XTE J1810-197, derived with a Chndra-HRC Target of Opportunity observation carried out in November 2003. We also report the discovery of a likely IR…
During the last 10 years, INTEGRAL made a unique contribution to the study of accreting millisecond X-ray pulsars (AMXPs), discovering three of the 14 sources now known of this class. Besides increasing the number of known AMXPs, INTEGRAL…
We present an analysis of the apsidal motion and light curve parameters of 54 never-before-studied galactic Algol-type binaries. This is the first analysis of such a large sample of eccentric eclipsing binaries in our Galaxy, and has…
We present XMM-Newton and Chandra observations of 1E1048.1-5937, being the first to show evidence for a significant variation in the X-ray luminosity of this Anomalous X-ray Pulsar (AXP). While during the first XMM-Newton (2000 December)…
We present results obtained from X-ray observations of the anomalous X-ray pulsar (AXP) 4U 0142+61 taken between 2000-2007 using XMM-Newton, Chandra and Swift. In observations taken before 2006, the pulse profile is observed to become more…
We report on the detection of variability from the proposed IR counterpart to the Anomalous X-ray Pulsar (AXP) 1E1048.1-5937 based on Chandra and ESO optical/IR deep observations carried out in 2001-2002. Within the narrow Chandra…
After 6 years of quiescence, Anomalous X-ray Pulsar (AXP) 4U 0142+61 entered an active phase in 2006 March that lasted several months. During the active phase, several bursts were detected, and many aspects of the X-ray emission changed. We…
We report X-ray imaging, timing, and spectral studies of XTE J1810-197, a 5.54s pulsar discovered by Ibrahim et al. (2003) in recent RXTE observations. In a set of short exposures with the Chandra HRC camera we detect a strongly modulated…
Until 2004, Anomalous X-ray Pulsars (AXPs) were known as strong emitters of soft X-rays only (< 10 keV). The discovery of hard X-ray component from AXPs provided important insight about their emission properties while it posed a serious…