On ultracold molecular gas toward the galactic center

Abstract

view Abstract Citations (5) References (13) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On ultracold molecular gas toward the galactic center Zuckerman, B. ; Kuiper, T. B. H. Abstract Several positions near the galactic center (Sgr A) in the J=1-0 rotational transitions of (C-12)O, (C-13)O, and C(O-18) were observed in order to better understand the nature of the 'very cold' molecular gas whose existence was first stressed by Liszt and his colleagues (1975, 1977). It is established that several dips in the (C-12)O spectra are due to optically thick clouds of foreground CO with relatively low excitation temperatures (Tex). Tex is found to be greater than about 5.3 K for all such (C-12)O clouds in all five observed directions. Such clouds fall at the extreme low end of the measured range of Tex for nearby dark clouds, but would, nonetheless, generally be detected in sensitive emission surveys of galactic CO. Publication: The Astrophysical Journal Pub Date: February 1980 DOI: 10.1086/157686 Bibcode: 1980ApJ...235..840Z Keywords: Carbon Monoxide; Emission Spectra; Galactic Nuclei; Infrared Astronomy; Interstellar Gas; Molecular Gases; Absorption Spectra; Milky Way Galaxy; Optical Thickness; Spectral Resolution; Temperature Effects; Astrophysics full text sources ADS |