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arXiv · 0711.4182

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

Abstract

Suzaku TOO observation of the anomalous X-ray pulsar CXOU J164710.2-455216 was performed on 2006 September 23--24 for a net exposure of 38.8 ks. During the observation, the XIS was operated in 1/8 window option to achieve a time resolution of 1 s. Pulsations are clearly detected in the XIS light curves with a barycenter corrected pulse period of 10.61063(2) s. The XIS pulse profile shows 3 peaks of different amplitudes with RMS fractional amplitude of ~11% in 0.2--6.0 keV energy band. Though the source was observed with the HXD of Suzaku, the data is highly contaminated by the nearby bright X-ray source GX 340+0 which was in the HXD field of view. The 1-10 keV XIS spectra are well fitted by 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}. The observed source flux in 1-10 keV energy range is calculated to be 2.6 x 10^{-11} ergs cm^{-2} s^{-1} with significant contribution from the soft blackbody component (kT = 0.61 keV). Pulse phase resolved spectroscopy of XIS data 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 changes between 2.2-2.7 km and 0.28-0.38 km (assuming the source distance to be 5 kpc) over pulse phases for the soft and hard components, respectively. The details of the results obtained from the timing and spectral analysis is presented.

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BibTeXRIS

Sachindra Naik, Tadayasu Dotani, Nobuyuki Kawai, Motohide Kokubun, Takayasu Anada, Mikio Morii, Tatehiro Mihara, Teruaki Enoto, Madoka Kawaharada, Toshio Murakami, Yujin E. Nakagawa, Hiromitsu Takahashi, Yukikatsu Terada, Atsumasa Yoshida. 2007-11-27. Suzaku Observation of the Anomalous X-ray Pulsar CXOU J164710.2--455216. https://doi.org/10.1093/pasj%2F60.2.237

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