Suzaku Observations of M 82 X-1 : Detection of a Curved Hard X-Ray Spectrum
Suzaku Observations of M 82 X-1 : Detection of a Curved Hard X-Ray Spectrum
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DOI：
10.1093/pasj/61.sp1.s263
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发表时间：
2008-09
影响因子：
2.3
通讯作者：
R. Miyawaki;K. Makishima;S. Yamada;P. Gandhi;T. Mizuno;A. Kubota;T. Tsuru;H. Matsumoto
中科院分区：
文献类型：
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作者：
R. Miyawaki;K. Makishima;S. Yamada;P. Gandhi;T. Mizuno;A. Kubota;T. Tsuru;H. Matsumoto
一份关于朱雀观测星暴星系M 82中超亮X射线源X-1的报告，在2005年10月进行了三次，每次曝光量为30千秒。来自原子核周围半径为30的区域的XIS信号定义了2-10 keV的2.1 × 10 - 11 erg·s·1·cm-2的通量，可归因于点源。3.2-10 keV的光谱比光子指数为1.7的幂律略凸。在所有的观测中，HXD还探测到了来自M 82的高达20 keV的信号，12-20 keV的通量为4.4 × 10 × 12 erg·s·1·cm·2。HXD谱比XIS谱陡。XIS和HXD光谱可以通过截止幂律模型或类似的弯曲模型联合再现。在检测到的宽带信号中，1= 3 to 2=3可归因于X-1，而其余的可归因于M 82中的其它离散源。不管这些污染物的模型如何，X-1的光谱比幂律曲线更弯曲，其辐射热光度为（1.5-3）10 40 erg s-1。这些结果被解释为来自100-200太阳质量的黑洞的康普顿化辐射，大约以爱丁顿光度辐射。
A report is presented on Suzaku observations of the ultra-luminous X-ray source X-1 in the starburst galaxy M 82, made three times in 2005 October for an exposure of � 30 ks each. The XIS signals from a region of radius 3 0 around the nucleus defined a 2–10 keV flux of 2.1 � 10 � 11 erg s � 1 cm � 2 attributable to point sources. The 3.2–10 keV spectrum was slightly more convex than a power-law with a photon index of 1.7. In all observations, the HXD also detected signals from M 82 up to � 20 keV, at a 12–20 keV flux of 4.4 � 10 � 12 erg s � 1 cm � 2 . The HXD spectrum was steeper than that of the XIS. The XIS and HXD spectra can be jointly reproduced by a cutoff power-law model, or similar curved models. Of the detected wide-band signals, 1= 3t o 2=3 are attributable to X-1, while the remainder to other discrete sources in M 82. Regardless of the modeling of these contaminants, the spectrum attributable to X-1 is more curved than a power-law, with a bolometric luminosity of (1.5–3) � 10 40 erg s � 1 . These results are interpreted as Comptonized emission from a black hole of 100–200 solar masses, radiating roughly at the Eddington luminosity.