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Title: Fe K LINE COMPLEX IN THE NUCLEAR REGION OF NGC 253

Journal Article · · Astrophysical Journal Letters
; ;  [1]
  1. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), 3-1-1 Yoshinodai, Chuo-ku Sagamihara, Kanagawa, 252-5210 (Japan)

A bright, nearby edge-on starburst galaxy, NGC 253, was studied using the Suzaku, XMM, and Chandra X-ray observatories. With Suzaku and XMM we detected 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 {approx}60 arcsec{sup 2} region around the nucleus, which suggests that the source is not only the buried active galactic nucleus. The flux of highly ionized Fe lines can be explained by the accumulation of 10-1000 supernova remnants that are the result of high star-forming activity, while the Fe I line flux is consistent with the fluorescent line emission expected with the molecular clouds in the region.

OSTI ID:
22047323
Journal Information:
Astrophysical Journal Letters, Vol. 742, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
Country of Publication:
United States
Language:
English