skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A PANCHROMATIC VIEW OF NGC 602: TIME-RESOLVED STAR FORMATION WITH THE HUBBLE AND SPITZER SPACE TELESCOPES

Journal Article · · Astrophysical Journal
 [1];  [2];  [3]
  1. Leiden Observatory, Leiden University, Leiden (Netherlands)
  2. Department of Physics and Astronomy, Johns Hopkins University, Baltimore, 3400 N. Charles Street, Baltimore, MD (United States)
  3. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD (United States)

We present the photometric catalogs for the star-forming cluster NGC 602 in the wing of the Small Magellanic Cloud covering a range of wavelengths from optical (HST/ACS F555W, F814W, and SMARTS/ANDICAM V, I) to infrared (Spitzer/IRAC 3.6, 4.5, 5.8, and 8 {mu}m and MIPS 24 {mu}m). Combining this with Infrared Survey Facility near-infrared photometry (J, H, K{sub s} ), we compare the young main sequence (MS) and pre-main sequence (PMS) populations prominent in the optical with the current young stellar object (YSO) populations revealed by the infrared. We analyze the MS and PMS population with isochrones in color-magnitude diagrams to derive ages and masses. The optical data reveal {approx}565 PMS candidates, low-mass Stage III YSOs. We characterize {approx}40 YSOs by fitting their spectral energy distributions to a grid of models (Robitaille et al.) to derive luminosities, masses, and evolutionary phase (Stages I-III). The higher resolution HST images reveal that {approx}70% of the YSO candidates are either multiples or protoclusters. For YSOs and PMS sources found in common, we find a consistency in the masses derived. We use the YSO mass function to derive a present-day star formation rate of {approx}0.2-1.0 M{sub sun} yr{sup -1} kpc{sup -2}, similar to the rate derived from the optical star formation history suggesting a constant star formation rate for this region. We demonstrate a progression of star formation from the optical star cluster center to the edge of the star-forming dust cloud. We derive lifetimes of a few 10{sup 5} years for the YSO Stages I and II.

OSTI ID:
21574614
Journal Information:
Astrophysical Journal, Vol. 730, Issue 2; Other Information: DOI: 10.1088/0004-637X/730/2/78; ISSN 0004-637X
Country of Publication:
United States
Language:
English