Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-04-19
Astronomy and Astrophysics
Astrophysics
Preprint in Manuscript format; 30 pages including 10 figures
Scientific paper
10.1051/0004-6361:20020601
We present 0.95--2.5 micron moderate (R = 500) resolution spectra of 19 ISOCAM detected sources in the Chamaeleon I dark cloud. Thirteen of these stars are candidate very low mass members of the cloud proposed by Persi et al. (2000 A&A 357:219) on basis of the mid-IR color excess. The sample also includes a bona-fide young brown dwarf (Cha Halpha 1), a transition --stellar/sub-stellar-- object (Cha Halpha 2), one previously known T Tauri star (Sz 33) and three ISOCAM sources with no mid-IR excess. The spectra of the mid-IR color excess sources are relatively flat and featureless in this wavelength range. Both atomic and molecular lines (when in absorption) are partially veiled suggesting the presence of continuum emission from circumstellar dust. In addition some of the sources show Paschen and Brackett lines in emission. We apply the 2 micron water vapor index defined by Wilking et al. (1999 AJ 117:469) to estimate spectral types. These stars have spectral types M0--8. We use Persi et al.'s stellar luminosity determinations, in combination with D'Antona & Mazzitelli latest pre-main sequence evolutionary tracks, to estimate masses and ages. The ISOCAM detected mid-IR excess sources have sub-solar masses down to the H-burning limit and a median age of few x 10^6 yr, in good agreement with the higher mass members of this cloud.
Gomez Mercedes
Persi Paolo
No associations
LandOfFree
Near-infrared spectra of ISO selected Chamaeleon I young stellar objects does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Near-infrared spectra of ISO selected Chamaeleon I young stellar objects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Near-infrared spectra of ISO selected Chamaeleon I young stellar objects will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-47907