Suzaku Observation of the Anomalous X-ray Pulsar CXOU J164710.2--455216

[著者版]A Suzaku TOO observation of CXOU J164710.2-455216 was performed on 2006 September 23-24 for a net exposure of 38.8 ks. Pulsations were clearly detected in the XIS light curves with a pulse period of 10.61063(2) s. The XIS pulse profile is found to be highly non-sinusoidal. It shows 3 peaks of different amplitudes with an RMS fractional amplitude of similar to 11% in the 0.2-6.0 keV energy band. The 1 -10 keV XIS spectra were well fitted by two different models consisting of a power-law and a blackbody component and two blackbody components, respectively. Although both the models are statistically acceptable, a difference in the pulse profiles at soft (0.2-6.0 keV) and hard (6-12keV) X-rays favors the model consisting of two blackbody components. The temperatures of two blackbody components are found to be 0.61 +/- 0.01 keV and 1.22 +/- 0.06 keV, and the value of the absorption column density is 1.73 +/- 0.03 x 10(22) atoms cm(-2). Pulse phase resolved spectroscopy shows that the flux of the soft blackbody component consists of three narrow peaks, whereas the flux of the other component shows a single peak over the pulse period of the AXP. The blackbody radii change between 2.2-2.7 km and 0.28-0.38 km (assuming the source distance to be 5 kpc) over the pulse phases for the soft and hard components, respectively. The details of the results obtained from the timing and spectral analyses are presented