Year: 1999
Type: article
Abstract: The COBE Far Infrared Absolute Spectrophotometer (FIRAS) observations constitute an unbiased survey over the wavelength range from 100 μm to 1 cm over 99% of the sky. Improved calibration of the FIRAS instrument and the inclusion of all of the FIRAS data allow an improved signal-to-noise ratio determination of the spectral lines by a factor of ~2 over our previous results. The resolution is low (0.45 cm -1 ), so only the strongest lines are observable. The CO chain from J = 1-0 to J = 8-7 is observed toward the Galactic center. The line ratios are roughly consistent with a 40 K excitation temperature. The 157.7 μm C II and 205.3 μm N II lines are observable over most of the sky. The 370.4 and 609.1 μm lines of C I and the 121.9 μm line of N II are observed in the Galactic plane. The line ratios at the Galactic center are consistent with a density of n 0 ~ 30 cm -3 and a UV flux of G 0 ≈ 15 μW m -2 sr -1 (10 Habing units). The 269 μm H 2 O line is observed toward the Galactic center in absorption.
Source: The Astrophysical Journal
DOI: 10.1086/307962
Authors: D. J. Fixsen, C. L. Bennett, J. C. Mather
Institutions: Goddard Space Flight Center, Raytheon (United States)
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Funder: Astrophysics Division
OpenAlex ID: W2059309055