Distribution of SI II in the Galactic center

Abstract

view Abstract Citations (11) References (31) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Distribution of SI II in the Galactic Center Graf, P. ; Herter, T. ; Gull, G. E. ; Houck, J. R. Abstract A map of the Galactic center region in the forbidden Si II 34.8-micron line is presented. The line emission arises from within the photodissociation region (PDR) associated with the neutral gas ring surrounding an ionized gas core confined within 2 pc of the Galactic center. Si II is a useful probe of the inner regions of the ring since it is always optically thin. The Si II data, when analyzed in conjunction with O I, C II, and molecular measurements, outlines the transition region between the PDR and the surrounding molecular cloud. The Si II emission is found to extend beyond that of the O II into the neutral gas ring. Although the interpretation is not unique, the data are consistent with a constant gas-phase abundance of silicon within the inner part of the PDR while the gaseous silicon is depleted by molecule formation in the transition region. Publication: The Astrophysical Journal Pub Date: July 1988 DOI: 10.1086/166513 Bibcode: 1988ApJ...330..803G Keywords: Abundance; Galactic Nuclei; Line Spectra; Milky Way Galaxy; Molecular Clouds; Silicon; Carbon; Forbidden Transitions; Ionized Gases; Neutral Gases; Optical Thickness; Oxygen; Photodissociation; Astrophysics; GALAXIES: THE GALAXY; GALAXIES: NUCLEI; INTERSTELLAR: ABUNDANCES; INTERSTELLAR: MOLECULES; RADIATION MECHANISMS full text sources ADS |