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X-Ray Timing, Spectroscopy and Photometry of the Anomalous X-Ray Pulsar Candidate CXOU J010043.1-721134

M. B. McGarry·B. M. Gaensler·S. M. Ransom·V. M. Kaspi·S. Veljkovik
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Abstract

We present new X-ray timing and spectral results on the 8.0-second X-ray pulsar CXOU J010043.1-721134 from a series of observations using the Chandra X-ray Observatory. We find a spin period in 2004 January of 8.020392pm0.000009 seconds. Comparison of this to 2001 Chandra observations implies a period derivative dot{P} = (1.88 pm 0.08) times 10^{-11} s s^{-1}, leading to an inferred dipole surface magnetic field of 3.9 times 10^{14} G. The spectrum is well fit to an absorbed blackbody of temperature kT = 0.38pm0.02 keV with a power law tail of photon index Gamma = 2.0pm0.6. We find that the source has an unabsorbed X-ray flux (0.5-10 keV) of 4(+2-1) times 10^{-13} erg cm^{-2} s^{-1} and a corresponding X-ray luminosity of ~2 times 10^{35} erg s^{-1} for a distance of 60 kpc. These properties support classification of CXOU J010043.1-721134 as the seventh confirmed anomalous X-ray pulsar,the eleventh confirmed magnetar, and the first magnetar to be identified in the Small Magellanic Cloud.

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M. B. McGarry, B. M. Gaensler, S. M. Ransom, V. M. Kaspi, S. Veljkovik. 2005-06-06. X-Ray Timing, Spectroscopy and Photometry of the Anomalous X-Ray Pulsar Candidate CXOU J010043.1-721134. https://doi.org/10.1086/432441

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