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arXiv 1202.0400astro-ph.HE
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Seyfert 2星系IRAS 00521-7054中可能存在的一条超强宽Fe Ka发射线

A possible ultra strong and broad Fe Ka emission line in Seyfert 2 galaxy IRAS 00521-7054

Ying Tan, Junxian Wang, Xinwen Shu, Youyuan Zhou

摘要:

我们提出了XMM牛顿光谱的塞弗特2星系IRAS 00521-7054。在~6 keV(观察者坐标系)处的强特征可以与向下延伸到3 keV的强(在静止坐标系中EW=1.3+-0.3keV)和宽的Fe Ka线正式拟合。下面的X射线连续谱可以用吸收幂律(Gamma = 1.8+-0.2,N_H = 5.9 x 10^22 cm^-2)加上软分量来拟合。如果由于X射线照射的吸积盘的相对论性模糊反射,则超大质量黑洞的自旋被限制为0.97^+0.03_-0.13(对于一个感兴趣的参数,误差在90%置信水平),并且在37 ± 4度的倾角下观察吸积系统。这将是第一个2型活动星系核被发现的强红色Fe Ka翼,这需要一个快速旋转的SMBH。异常大的EW将表明在该源中光弯曲效应很强。或者,可以用双吸收体模型来拟合光谱(尽管对于283 d.o.f,整体chi ^2要高出约6),其中N_H1 = 7.0 x 10^22 cm^-2覆盖了100%的X射线源,N_H2 = 21.7 x 10^22 cm^-2覆盖了71%的X射线源,这不需要额外宽的Fe Ka线。

英文摘要:

We present XMM-Newton spectra of the Seyfert 2 Galaxy IRAS 00521-7054. A strong feature at ~6 keV (observer's frame) can be formally fitted with a strong (EW=1.3+-0.3 keV in the rest frame) and broad Fe Ka line, extending down to 3 keV. The underlying X-ray continuum could be fitted with an absorbed powerlaw (with Gamma = 1.8+-0.2 and N_H = 5.9 x 10^22 cm^-2) plus a soft component. If due to relativistically smeared reflection by an X-ray illuminated accretion disk, the spin of the supermassive black hole is constrained to be 0.97^+0.03_-0.13 (errors at 90% confidence level for one interesting parameter), and the accretion system is viewed at an inclination angle of 37+-4 degree. This would be the first type 2 AGN reported with strong red Fe Ka wing detected which demands a fast rotating SMBH. The unusually large EW would suggest that the light bending effect is strong in this source. Alternatively, the spectra could be fitted by a dual absorber model (though with a global chi^2 higher by ~ 6 for 283 d.o.f) with N_H1 = 7.0 x 10^22 cm^-2 covering 100% of the X-ray source, and N_H2 = 21.7 x 10^22 cm^-2 covering 71%, which does not require an extra broad Fe Ka line.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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