A puzzling paucity of double peaked X-ray pulsars

X-ray pulsars: a review

Accreting X-ray pulsars are among the most luminous objects in the X-ray sky. In highly magnetized neutron stars (B ∼ 1012 G), the flow of matter is dominated by the strong magnetic field. The general properties of accreting X-ray binaries are presented, focusing on the spectral characteristics of the systems. The use of cyclotron lines as a tool to directly measure a neutron star’s magnetic fi...

(Anomalous) X-ray Pulsars

Prior to the commissioning of BeppoSAX and the Rossi X-ray Timing Observatory in 1996, the so-called “Anomalous” X-ray Pulsars (AXPs) were considered very mysterious sources, because the energy source for their bright X-ray emission was unknown. At the time, there were only 3 known members of this class. They were distinguished by having periods in the narrow range 6–9 s, showing approximately ...

The Anomalous X-ray Pulsars

Puzzling Pulsars and Supernova Remnants

The fact that the majority of the youngest radio pulsars are surrounded by expanding supernova remnants is strong evidence that neutron stars are produced in the supernovae of massive stars. In many cases, the pulsar appears significantly offset from the geometric centre of the supernova remnant, indicating that the neutron star has moved away from the site of the explosion with a substantial s...

Polarization properties of X-ray millisecond pulsars

Radiation of X-ray bursts and of accretion shocks in weakly magnetized neutron stars in low-mass X-ray binaries is produced in plane-parallel atmospheres dominated by electron scattering. We first discuss polarization produced by single (non-magnetic) Compton scattering, in particular the depolarizing effect of high electron temperature, and then the polarization due to multiply electron scatte...