Measurements of forbidden line radiation of AR II /6.99 microns/ in W3 IRS 1

Abstract

view Abstract Citations (7) References (17) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Measurements of forbidden line radiation of AR II /6.99 microns/ in W3 IRS 1 Herter, T. ; Pipher, J. L. ; Helfer, H. L. ; Willner, S. P. ; Puetter, R. C. ; Rudy, R. J. ; Soifer, B. T. Abstract Observations of the [Ar II] (6.99 μm) line flux in W3 IRS 1 are combined with previously obtained measurements of the [Ar III] (8.99 μm) line flux. The observed ratio of [Ar II]/[Ar III] is inconsistent with the calculated ratio for an H II region with the densities required by radio observations and with a central 40,000-45,000 K star with atmosphere as described by a Mihalas model. A softer effective UV radiation field is required; a dusty model we had previously invoked fits the observations. In addition we determine that the argon abundance is n(Ar)/n(H) ≈ 8 × 10-6, a value about twice that usually adopted for normal solar abundance; however, there are uncertainties in the extinction and the model which do not allow us to preclude solar abundance. Publication: The Astrophysical Journal Pub Date: March 1981 DOI: 10.1086/158728 Bibcode: 1981ApJ...244..511H Keywords: Argon; Forbidden Bands; Hydrogen Clouds; Infrared Spectra; Nebulae; Abundance; Astronomical Models; Stellar Atmospheres; Astronomy full text sources ADS |