TY - JOUR
T1 - The XMM-Newton extended survey of the Taurus molecular cloud (XEST)
AU - Güdel, M.
AU - Briggs, K. R.
AU - Arzner, K.
AU - Audard, M.
AU - Bouvier, J.
AU - Feigelson, E. D.
AU - Franciosini, E.
AU - Glauser, A.
AU - Grosso, N.
AU - Micela, G.
AU - Monin, J. L.
AU - Montmerle, T.
AU - Padgett, D. L.
AU - Palla, F.
AU - Pillitteri, I.
AU - Rebull, L.
AU - Scelsi, L.
AU - Silva, B.
AU - Skinner, S. L.
AU - Stelzer, B.
AU - Telleschi, A.
PY - 2007/6
Y1 - 2007/6
N2 - Context. The Taurus Molecular Cloud (TMC) is the nearest large star-forming region, prototypical for the distributed mode of lowmass star formation. Pre-main sequence stars are luminous X-ray sources, probably mostly owing to magnetic energy release. Aims. The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) presented in this paper surveys the most populated ≈5 square degrees of the TMC, using the XMM-Newton X-ray observatory to study the thermal structure, variability, and long-term evolution of hot plasma, to investigate the magnetic dynamo, and to search for new potential members of the association. Many targets are also studied in the optical, and high-resolution X-ray grating spectroscopy has been obtained for selected bright sources. Methods. The X-ray spectra have been coherently analyzed with two different thermal models (2-component thermal model, and a continuous emission measure distribution model). We present overall correlations with fundamental stellar parameters that were derived from the previous literature. A few detections from Chandra observations have been added. Results. The present overview paper introduces the project and provides the basic results from the X-ray analysis of all sources detected in the XEST survey. Comprehensive tables summarize the stellar properties of all targets surveyed. The survey goes deeper than previous X-ray surveys of Taurus by about an order of magnitude and for the first time systematically accesses very faint and strongly absorbed TMC objects. We find a detection rate of 85% and 98% for classical and weak-line T Tau stars (CTTS resp. WTTS), and identify about half of the surveyed protostars and brown dwarfs. Overall, 136 out of 169 surveyed stellar systems are detected. We describe an X-ray luminosity vs. mass correlation, discuss the distribution of X-ray-to-bolometric luminosity ratios, and show evidence for lower X-ray luminosities in CTTS compared to WTTS. Detailed analysis (e.g., variability, rotation-activity relations, influence of accretion on X-rays) will be discussed in a series of accompanying papers.
AB - Context. The Taurus Molecular Cloud (TMC) is the nearest large star-forming region, prototypical for the distributed mode of lowmass star formation. Pre-main sequence stars are luminous X-ray sources, probably mostly owing to magnetic energy release. Aims. The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) presented in this paper surveys the most populated ≈5 square degrees of the TMC, using the XMM-Newton X-ray observatory to study the thermal structure, variability, and long-term evolution of hot plasma, to investigate the magnetic dynamo, and to search for new potential members of the association. Many targets are also studied in the optical, and high-resolution X-ray grating spectroscopy has been obtained for selected bright sources. Methods. The X-ray spectra have been coherently analyzed with two different thermal models (2-component thermal model, and a continuous emission measure distribution model). We present overall correlations with fundamental stellar parameters that were derived from the previous literature. A few detections from Chandra observations have been added. Results. The present overview paper introduces the project and provides the basic results from the X-ray analysis of all sources detected in the XEST survey. Comprehensive tables summarize the stellar properties of all targets surveyed. The survey goes deeper than previous X-ray surveys of Taurus by about an order of magnitude and for the first time systematically accesses very faint and strongly absorbed TMC objects. We find a detection rate of 85% and 98% for classical and weak-line T Tau stars (CTTS resp. WTTS), and identify about half of the surveyed protostars and brown dwarfs. Overall, 136 out of 169 surveyed stellar systems are detected. We describe an X-ray luminosity vs. mass correlation, discuss the distribution of X-ray-to-bolometric luminosity ratios, and show evidence for lower X-ray luminosities in CTTS compared to WTTS. Detailed analysis (e.g., variability, rotation-activity relations, influence of accretion on X-rays) will be discussed in a series of accompanying papers.
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U2 - 10.1051/0004-6361:20065724
DO - 10.1051/0004-6361:20065724
M3 - Review article
AN - SCOPUS:34250314981
SN - 0004-6361
VL - 468
SP - 353
EP - 377
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
IS - 2
ER -