2006/11/21 by M. P. Muno, F. K. Baganoff, Frederick K. Baganoff +4 · 3 citations
Decision Sciences · Engineering · Physics and Astronomy · #Astronomical Observations and Instrumentation #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Ejecta #Galactic Center #Galaxy #Luminosity #Molecular cloud #Observatory #Physics #Planetary nebula #Reflection (computer programming) #Reflection nebula #Scientific Measurement and Uncertainty Evaluation #Stars #Supernova #astro-ph
paper · pdf · doi:10.1086/512236
published as Astrophys.J.656:L69-L72,2007 · 5 pages, 3 figures (2 color). submitted to ApJL
arxiv created 2006/11/21 · openalex publication_date 2007/01/31 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
On the basis of 3 years of deep observations of the Galactic center with the Chandra X-Ray Observatory , we report the discovery of changes in the intensities and morphologies of two hard X-ray nebulosities. The nebulosities are dominated by fluorescent iron emission and are coincident with molecular clouds. The morphological changes are manifest on parsec scales, which requires that these iron features are scattered X-rays from a 2 or 3 year long outburst of a point source (either Sgr A* or an X-ray binary) with a luminosity of at least 10 37 ergs s -1 . The variability precludes the hypotheses that these nebulae either are produced by keV electrons bombarding molecular clouds or are iron-rich ejecta from supernovae. Moreover, the morphologies of the reflection nebulae implies that the dense regions of the clouds are filamentary, with widths of ≈0.3 pc and lengths of ≈2 pc.