AN ALL-SKY SAMPLE OF INTERMEDIATE-MASS STAR-FORMING REGIONS

作者:Lundquist Michael J*; Kobulnicky Henry A; Alexander Michael J; Kerton Charles R; Arvidsson Kim
来源:Astrophysical Journal, 2014, 784(2): 111.
DOI:10.1088/0004-637X/784/2/111

摘要

We present an all-sky sample of 984 candidate intermediate-mass Galactic star-forming regions that are color selected from the Infrared Astronomical Satellite (IRAS) Point Source Catalog and morphologically classify each object using mid-infrared Wide-field Infrared Survey Explorer (WISE) images. Of the 984 candidates, 616 are probable star-forming regions (62.6%), 128 are filamentary structures (13.0%), 39 are point-like objects of unknown nature (4.0%), and 201 are galaxies (20.4%). We conduct a study of four of these regions, IRAS 00259+5625, IRAS 00420+5530, IRAS 01080+5717, and IRAS 05380+2020, at Galactic latitudes |b| %26gt; 5. using optical spectroscopy from the Wyoming Infrared Observatory, along with near-infrared photometry from the Two-Micron All Sky Survey, to investigate their stellar content. New optical spectra, color-magnitude diagrams, and color-color diagrams reveal their extinctions, spectrophotometric distances, and the presence of small stellar clusters containing 20-78M(circle dot) of stars. These low-mass diffuse star clusters contain similar to 65-250 stars for a typical initial mass function, including one or more mid-B stars as their most massive constituents. Using infrared spectral energy distributions we identify young stellar objects near each region and assign probable masses and evolutionary stages to the protostars. The total infrared luminosity lies in the range 190-960 L-circle dot, consistent with the sum of the luminosities of the individually identified young stellar objects.

  • 出版日期2014-4-1