H I self-absorption in the Southern Coalsack dust complex

Abstract

view Abstract Citations (18) References (35) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS H I self-absorption in the Southern Coalsack dust complex. Bowers, P. F. ; Kerr, F. J. ; Hawarden, T. G. Abstract A search for H I self-absorption features toward 23 globules or dark regions in the Southern Coalsack dust complex has resulted in the detection of a cold H I cloud surrounding three globules. The H I distribution is less clumpy and more extended than the OH and H2CO distributions associated with the globule complex, but it generally agrees with the dust distribution except at the positions of the globules. There is no evidence that the H I distribution is strongly peaked at the positions of the globules; rather, the globules appear to be embedded in the relatively uniform density H I cloud. At the position of one of the globules (globule 2) where sufficient data exist for comparison, the H I, OH, H2CO, and CO velocities agree to within their relative uncertainties. Elsewhere there appears to be a velocity gradient observable for H I but not for OH; the difference between these velocity distributions is not understood. Publication: The Astrophysical Journal Pub Date: October 1980 DOI: 10.1086/158330 Bibcode: 1980ApJ...241..183B Keywords: Cosmic Dust; Hydrogen Clouds; Radio Sources (Astronomy); Self Absorption; Astronomical Catalogs; Astronomical Maps; Centimeter Waves; Optical Thickness; Velocity Distribution; Astrophysics; Globules:Neutral Hydrogen full text sources ADS |