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arXiv · astro-ph/0502543

X-rays from Cepheus A East and West

Steven H. Pravdo·Yohko Tsuboi
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Abstract

We report the discovery of X-rays from both components of Cepheus A, East and West, with the XMM-Newton Observatory. HH 168 joins the ranks of other energetic Herbig Haro objects that are sources of T~10^6 K X-ray emission. The HH 168 effective temperature is T = 5.8 (+3.5,-2.3) x 10^6 K and its unabsorbed luminosity is 1.1 x 10^29 erg s^-1, making it hotter and less luminous than other representatives of its class. We also detect prominent X-ray emission from the complex of compact radio sources believed to be the power sources for Cep A. We call this source HWX and it is distinguished by its hard X-ray spectrum, T = 1.2 (+1.2,-0.5) x 10^8 K, and complex spatial distribution. It may arise from one or more protostars associated with the radio complex, the outflows, or a combination of the two. We detect 102 X-rays sources; many presumed to be pre-main sequence stars based upon the reddening of their optical/IR counterparts.

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Steven H. Pravdo, Yohko Tsuboi. 2005-02-25. X-rays from Cepheus A East and West. https://doi.org/10.1086/429988

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