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arXiv · 1110.5407

Fe K line complex in the nuclear region of NGC 253

Ikuyuki Mitsuishi·Noriko Y. Yamasaki·Yoh Takei
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Abstract

A bright, nearby edge-on starburst galaxy NGC 253 was studied using the Suzaku, XMM and Chandra X-ray observatories. We detected with Suzaku and XMM complex line structure of Fe K, which is resolved into three lines (Fe I at 6.4 keV, Fe XXV at 6.7 keV and Fe XXVI at 7.0 keV) around the center of NGC 253. Especially, the Fe I and Fe XXVI lines are the first clear detections, with a significance of >99.99 % and 99.89 % estimated by a Monte Carlo procedure. Imaging spectroscopy with Chandra revealed that the emission is distributed in ~60 arcsec^2 region around the nucleus, which suggests that the source is not only the buried AGN. The flux of highly ionized Fe lines can be explained by the accumulation of 10-1000 supernova remnants that are the result of high starforming activity, while the Fe I line flux is consistent with the fluorescent line emission expected with the molecular clouds in the region.

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Ikuyuki Mitsuishi, Noriko Y. Yamasaki, Yoh Takei. 2011-10-25. Fe K line complex in the nuclear region of NGC 253. https://doi.org/10.1088/2041-8205%2F742%2F2%2Fl31

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