Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-10-16
Astrophys.J.Suppl.173:104-136,2007
Astronomy and Astrophysics
Astrophysics
Scientific paper
10.1086/520114
I present a new census of the stellar population in the Chamaeleon I star-forming region. Using optical and near-IR photometry and followup spectroscopy, I have discovered 50 new members of Chamaeleon I, expanding the census of known members to 226 objects. Fourteen of these new members have spectral types later than M6, which doubles the number of known members that are likely to be substellar. I have estimated extinctions, luminosities, and effective temperatures for the known members, used these data to construct an H-R diagram for the cluster, and inferred individual masses and ages with the theoretical evolutionary models of Baraffe and Chabrier. The distribution of isochronal ages indicates that star formation began 3-4 and 5-6 Myr ago in the southern and northern subclusters, respectively, and has continued to the present time at a declining rate. The IMF in Chamaeleon I reaches a maximum at a mass of 0.1-0.15 M_sun, and thus closely resembles the IMFs in IC 348 and the Orion Nebula Cluster. In logarithmic units where the Salpeter slope is 1.35, the IMF is roughly flat in the substellar regime and shows no indication of reaching a minimum down to a completeness limit of 0.01 M_sun. The low-mass stars are more widely distributed than members at other masses in the northern subcluster, but this is not the case in the southern subcluster. Meanwhile, the brown dwarfs have the same spatial distribution as the stars out to a radius of 3 deg (8.5 pc) from the center of Chamaeleon I.
No associations
LandOfFree
The Stellar Population of the Chamaeleon I Star-Forming Region 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 The Stellar Population of the Chamaeleon I Star-Forming Region, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Stellar Population of the Chamaeleon I Star-Forming Region will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-714333