| | Near-infrared Photometric Variability of Stars Toward the Chamaeleon I Molecular Cloud |
 | | The variables can be grouped into a population of bright, red objects that are associated with the Chamaeleon I association, and a population of faint, blue variables that are dispersed over the full 6 deg of the survey and are likely field stars or older pre-main-sequence stars unrelated to the present-day Chamaeleon I molecular cloud. |
 | | The solid line in the color-magnitude diagram is the 2 Myr pre-main-sequence isochrone from D'Antona & Mazzitelli (1997,98) for stellar masses between 0.08 Mo and 3 Mo. The solid curves in the color-color diagram are the loci of red giant and main-sequence stars from Bessell & Brett (1988) in the 2MASS color system. |
 | | These panels show that the largest concentration of variable stars is toward the Chamaeleon I molecular cloud despite the overall decrease in the stellar surface density, indicating many of the variable stars must be associated with the Chamaeleon I molecular cloud. |
| www.astro.caltech.edu /~jmc/variables/cham1 (1204 words) |