XMM-Newton study of the Serpens star-forming region
Abstract
We analyze a XMM-Newton X-ray observation of the Serpens dark cloud with a total MOS-equivalent exposure time of 57 ksec. We find 45 individual X-ray sources. None of the class 0 protostars, only one of the class I protostars, and two of the flat-spectrum objects in the region are detected in X-rays. The optically invisible flat-spectrum source EC 95, a very young intermediate mass object, is the strongest X-ray source in the Serpens cloud. The analysis of its X-ray spectrum shows that the hydrogen column density towards EC 95 is considerably lower than expected from the extinction determined from near-IR spectroscopy and photometry. Possible reasons for this inconsistency are discussed.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 2003
- DOI:
- 10.1051/0004-6361:20031322
- Bibcode:
- 2003A&A...410..951P
- Keywords:
-
- open clusters and associations: individual: Serpens dark cloud;
- stars: formation;
- stars: coronae;
- stars: low-mass;
- brown dwarfs;
- stars: pre-main sequence;
- X-rays: stars