EXTINCTION AND DISTANCE TO ANOMALOUS X-RAY PULSARS FROM X-RAY SCATTERING HALOS

(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

Extinction Columns and Intrinsic X-ray Spectra of the Anomalous X-ray Pulsars

The X-ray spectra of Anomalous X-ray Pulsars have long been fit by smooth, empirical models such as the sum of a black-body plus a power law. These reproduce the ∼ 0.5 to 10 keV range well, but fail at lower and higher energies, grossly over-predicting the optical and under-predicting the hard X-ray emission. A poorly constrained source of uncertainty in determining the true, intrinsic spectra,...

Glitches in Anomalous X-ray Pulsars

We report on 8.7 and 7.6 yr of Rossi X-ray Timing Explorer (RXTE) observations of the Anomalous X-ray Pulsars (AXPs) RXS J170849.0−400910 and 1E 1841−045, respectively. These observations, part of a larger RXTE AXP monitoring program, have allowed us to study the long-term timing, pulsed flux, and pulse profile evolution of these objects. We report on four new glitches, one from RXS J170849.0−4...

Recent Progress on Anomalous X - ray Pulsars

I review recent observational progress on Anomalous X-ray Pulsars, with an emphasis on timing, variability, and spectra. Highlighted results include the recent timing and flux stabilization of the notoriously unstable AXP 1E 1048.1−5937, the remarkable glitches seen in two AXPs, the newly recognized variety of AXP variability types, including outbursts, bursts, flares, and pulse profile changes...