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arXiv · astro-ph/0208582

Hard X-ray emission from a young massive star-forming cluster

Abstract

We report the detection of hard X-ray emission (>2 keV) from a number of point sources associated with the very young massive star-forming region IRAS 19410+2336. The X-ray emission is detected from several sources located around the central and most deeply embedded mm continuum source, which remains undetected in the X-ray regime. All X-ray sources have K-band counterparts, and those likely belonging to the evolving massive cluster show near-infrared colors in the 2MASS data indicative of pre-main-sequence stages. The X-ray luminosities around 10^{31} erg/s are at the upper end of luminosities known for low-mass pre-main-sequence sources, and mass estimates based on the infrared data indicate that at least some of the X-ray detected sources are intermediate-mass objects. Therefore, we conclude that the X-ray emission is due to intermediate-mass pre-main-sequence Herbig Ae/Be stars or their precursors. The emission process is possibly due to magnetic star-disk interaction as proposed for their low-mass counterparts.

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H. Beuther, J. Kerp, T. Preibisch, T. Stanke, P. Schilke. 2002-08-30. Hard X-ray emission from a young massive star-forming cluster. https://doi.org/10.1051/0004-6361%3A20021261

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