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arXiv · astro-ph/0301081

Near-infrared Spectra of Chamaeleon I Stars

M. Gomez·D. Mardones
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Abstract

We present low resolution (R = 500) near-infrared spectra of 46 candidate young stellar objects in the Chamaeleon I star-forming region recently detected in several deep photometric surveys of the cloud. Most of these stars have K < 12. In addition, we present spectra of 63 previously known southern hemisphere young stars mainly belonging to the Chamaeleon I and Lupus dark clouds. We describe near-infrared spectroscopic characteristics of these stars and use the water vapor indexes to derive spectral types for the new objects. Photometric data from the literature are used to estimate the bolometric luminosities of all sources. We apply D'Antona & Mazzitelli (1998) pre-main sequence evolutionary tracks and isocrones to derive masses and ages. We detect two objects with mass below the H burning limit among the 46 new candidates. One of this object (PMK99 IR Cha INa1) is the likely driving source of a bipolar outflow in the northern region of the cloud.

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M. Gomez, D. Mardones. 2003-01-06. Near-infrared Spectra of Chamaeleon I Stars. https://doi.org/10.1086/368391

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