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

A Suzaku TOO observation of CXOU J164710.2-455216 was performed on 2006 September 23-24 for a net exposure of 38.8ks. 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 ∼11% in the 0.2-6.0keV energy band. The 1-10keV 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 (0.2-6.0keV) 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±0.01keV and 1.22±0.06keV, and the value of the absorption column density is 1.73±0.03 ×10²² atomscm^-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 2.2-2.7km and 0.28-0.38km (assuming the source distance to be 5kpc) 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.