The nature of the radio and infrared sources in S140

Journal Article · Wed Nov 01 04:00:00 EST 1989 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/168002· OSTI ID:7017760

Evans, II, N J; Mundy, L G; Kutner, M L; Depoy, D L ^[1]

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1. Texas Univ., Austin (USA) Maryland Univ., College Park (USA) Rensselaer Polytechnic Institute, Troy, NY (USA) National Optical Astronomical Observatories, Tucson, AZ (USA)

Observations of the S140 molecular cloud have been obtained with the VLA at 6 and 2 cm and with the KPNO infrared camera at 1.2, 1.65, and 2.2 microns. Radio continuum emission is seen from all three mid-infrared sources, IRS 1, 2, and 3. The near-infrared images show IRS 1 and 3 very clearly, but IRS 2 is not detected. Two additional radio sources not associated with mid-infrared sources, but coincident with strong, scattered, near-infrared emission, are probably clumps of shock-ionized gas, whose associated dust is illuminated by photons escaping through holes in the dense material around IRS 1. The near-infrared emission from IRS 1 and 3 is too strong to come from the stellar photospheres; instead it must be emission from hot dust grains. The absence of IRS 2 from the near-infrared images implies that the extinction toward IRS 2 must be much larger than the average. A substantial number of weaker sources are seen at 2 microns in the vicinity of IRS 1, indicating that many lower mass stars are also forming in the region. 38 refs.

• OSTI ID: 7017760
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 346; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC GASES
COSMIC RADIO SOURCES
ELECTROMAGNETIC RADIATION
FLUIDS
GASES
H2 REGIONS
INFRARED RADIATION
INTERSTELLAR SPACE
MAIN SEQUENCE STARS
MASS
NEBULAE
RADIATIONS
RADIOWAVE RADIATION
SPACE
STAR EVOLUTION
STARS