Anomalous X-Ray Scattering

The Dust-scattering X-ray Rings of the Anomalous X-ray Pulsar 1e1547.0–5408

On 2009 January 22 numerous strong bursts were detected from the anomalous X-ray pulsar 1E 1547.0–5408. Swift/XRT and XMM-Newton/EPIC observations carried out in the following two weeks led to the discovery of three X-ray rings centered on this source. The ring radii increased with time following the expansion law expected for a short impulse of X-rays scattered by three dust clouds. Assuming d...

(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

X-ray and Infrared Enhancement of Anomalous X-ray Pulsar

The long-term ( 1.5 yr) X-ray enhancement and the accompanying infrared enhancement light curves of the anomalous X-ray pulsar 1E 2259+586 following the major bursting epoch can be accounted for by the relaxation of a fallback disk that has been pushed back by a gamma-ray flare. The required burst energy estimated from the results of our model fits is low enough for such a burst to have remaine...

X-Ray Diffuse Scattering

In this research program, modern x-ray scattering techniques are used to study the structures and phase transitions in novel states of condensed matter. We have two principal experimental facilities. At M.I.T. we have three high-resolution computer controlled x-ray spectrometers using either a conventional or high intensity rotating anode x-ray generator. The angular resolution can be made as f...