OI and OIII in Sgr A: neutral and ionized gas at the Galactic center

Journal Article · Sat May 01 00:00:00 EDT 1982 · AIP Conf. Proc.; (United States)

DOI:https://doi.org/10.1063/1.33504· OSTI ID:5289966

Genzel, R; Watson, D; Townes, C; Lester, D; Dinerstein, H; Werner, M; Storey, J

We have mapped the /sup 3/P/sub 1/-/sup 3/P/sub 2/ fine structure line emission at 63 microns from neutral oxygen in the vicinity of the galactic center. The emission is extended over more than 4' and is centered on Sgr A West. We conclude that the bulk of the OI emission arises in a predominantly neutral region outside of the ionized central 3 pc of our galaxy. Assuming that the oxygen is collisionally excited by neutral hydrogen impact, we estimate that the gas temperatures in this region are >130K, that is, significantly higher than the dust temperature of 70K. The OI line center velocities change systematically along the galactic plane in a manner consistent with galactic rotation. However, the unusual velocity distribution and linewidths suggest that the motions have a large noncircular component and that there are large scale inhomogeneities in the OI-emitting gas. We also have detected the 88 micron /sup 3/P/sub 1/-/sup 3/P/sub 0/ fine structure line of OIII in a 45triangle-solid FWHM beam centered on Sgr A West. The ratio of this line intensity to that of 52 micron /sup 3/P/sub 2/-/sup 3/P/sub 1/ line indicates that most of the ionized gas in this region has electron density >10/sup 4/ cm/sup -3/.

• Research Organization: University of California, Berkeley, CA
• OSTI ID: 5289966
• Report Number(s): CONF-820139-
• Journal Information: AIP Conf. Proc.; (United States), Journal Name: AIP Conf. Proc.; (United States) Vol. 83:1; ISSN APCPC
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHARGED PARTICLES
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION SPECTRA
FABRY-PEROT INTERFEROMETER
FAR INFRARED RADIATION
FLUIDS
GALAXIES
GALAXY NUCLEI
GASES
INFRARED RADIATION
INFRARED SPECTRA
INTERFEROMETERS
IONIZED GASES
IONS
MEASURING INSTRUMENTS
MILKY WAY
NONMETALS
OXYGEN
OXYGEN IONS
RADIATIONS
SPECTRA