Measurements of forbidden line radiation of Ar II (6. 99. mu. m) in W3 IRS 1

Journal Article · Sun Mar 01 04:00:00 EST 1981 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/158728· OSTI ID:6385903

Herter, T; Pipher, J L; Helfer, H L; Willner, S P; Puetter, R C; Rudy, R J; Soifer, B T

Observations of the (Ar II) (6.99 ..mu..m) line flux in W3 IRS 1 are combined with previously obtained measurements of the (Ar III) (8.99 ..mu..m) 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 solar 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)roughly-equal8 x 10/sup -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.

• Research Organization: Department of Physics and Astronomy, University of Rochester
• OSTI ID: 6385903
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 244:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
ARGON IONS
CHARGED PARTICLES
COSMIC DUST
COSMIC RADIO SOURCES
DUSTS
ELECTROMAGNETIC RADIATION
ENERGY-LEVEL TRANSITIONS
FORBIDDEN TRANSITIONS
H2 REGIONS
INFRARED SPECTRA
IONS
NEBULAE
RADIATION FLUX
RADIATIONS
SPECTRA
ULTRAVIOLET RADIATION