Chandra observations of the anomalous X-ray pulsar 4U 0142+ 61

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 Γ= 3.35 (2), kT BB= 0.458 (3) keV, and N H= 0.91 (2)× 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 Γ, 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.

Año de publicación:

2003

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Fuente:

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