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Chandra Observations of the Anomalous X-ray Pulsar 4U 0142+61

Sandeep K. Patel·Chryssa Kouveliotou·Peter M. Woods·Allyn F. Tennant·Martin C. Weisskopf·Mark H. Finger·Colleen Wilson-Hodge·Ersin Gogus·Michiel van der Klis·Tomaso Belloni
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Abstract

We present X-ray imaging, timing, and phase resolved spectroscopy of the anomalous X-ray pulsar 4U 0142+61 using the Chandra X-ray Observatory. The spectrum is well described by a power law plus blackbody model with power law index = 3.35(2), kT_BB=0.458(3) keV, and N_H=0.91(2) x 10^{22} cm^{-2}$; we find no significant evidence for spectral features (0.5-7.0 keV). Time resolved X-ray spectroscopy shows evidence for evolution in phase in either index, or KT_BB, or some combination thereof as a function of pulse phase. We derive a precise X-ray position for the source and determine its spin period, P=8.68866(30) s. We have detected emission beyond 4 arcsec from the central source and extending beyond 100 arcsec, likely due to dust scattering in the interstellar medium.

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Sandeep K. Patel, Chryssa Kouveliotou, Peter M. Woods, Allyn F. Tennant, Martin C. Weisskopf, Mark H. Finger, Colleen Wilson-Hodge, Ersin Gogus, Michiel van der Klis, Tomaso Belloni. 2002-12-18. Chandra Observations of the Anomalous X-ray Pulsar 4U 0142+61. https://doi.org/10.1086/368072

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