Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-08-12
Astrophys.J. 616 (2004) 1042-1057
Astronomy and Astrophysics
Astrophysics
36 pages, 13 figures in JPEG format. Accepted for the publication in ApJ. Report is also available at : http://www.tifr.res.in
Scientific paper
10.1086/425068
We present sub-arcsecond (FWHM ~ 0".7), NIR JHKs-band images and a high sensitivity radio continuum image at 1280 MHz, using SIRIUS on UH 88-inch telescope and GMRT. The NIR survey covers an area of ~ 24 arcmin^2 with 10-sigma limiting mags of ~ 19.5, 18.4, and 17.3 in J, H, and Ks-band, respectively. Our NIR images are deeper than any JHK surveys to date for the larger area of NGC 7538 star forming region. We construct JHK CC and J-H/J and H-K/K CM diagrams to identify YSOs and to estimate their masses. Based on these CC and CM diagrams, we identified a rich population of YSOs (Class I and Class II), associated with the NGC 7538 region. A large number of red sources (H-K > 2) have also been detected around NGC 7538. We argue that these red stars are most probably PMS stars with intrinsic color excesses. Most of YSOs in NGC 7538 are arranged from the N-W toward S-E regions, forming a sequence in age: the diffuse H II region (N-W, oldest: where most of the Class II and Class I sources are detected); the compact IR core (center); and the regions with the extensive IR reflection nebula and a cluster of red young stars (S-E and S). We find that the slope of the KLF of NGC 7538 is lower than the typical values reported for the young embedded clusters, although equally low values have also been reported in the W3 Main star forming region. From the slope of the KLF and the analysis by Megeath et al. (1996), we infer that the embedded stellar population is comprised of YSOs with an age of ~ 1 Myr. Based on the comparison between models of PMS stars with the observed CM diagram we find that the stellar population in NGC 7538 is primarily composed of low mass PMS stars similar to those observed in the W3 Main star forming region.
Fukagawa Misato
Ghosh Sanjay K.
Momose Munetake
Nagashima Chie
Nagata Takahiro
No associations
LandOfFree
A near-infrared study of the NGC 7538 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 A near-infrared study of the NGC 7538 star forming region, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A near-infrared study of the NGC 7538 star forming region will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-574284