Title:	A search for localized sources of noncosmological deuterium near the Galactic Centre
Authors:	Lubowich, D.A. Anantharamaiah, K.R. Pasachoff, J.M.
Keywords:	deuterium galactic nuclei interstellar matter Milky wave galaxy abundance hydrogen clouds line spectra molecular clouds radio sources (astronomy)
Issue Date:	15-Oct-1989
Publisher:	The University of Chicago Press for the American Astronomical Society
Citation:	Astrophysical Journal, 1989, Vol.345, p770-775
Abstract:	The VLA at the 92 cm D I hyperfine transition was used to search for a possible localized concentration of atomic deuterium near the Galactic center over a velocity range of + or - 180 km/s. The search yielded an upper limit for the D column density N(D) = 7.78 x 10 to the 16th T(s)/sq cm where T(s) is the spin temperature of the D I hyperfine lines. For the smaller velocity range of + or - 30 km/s, a more sensitive upper limit of N(D) = 3.12 x 10 to the 16th T(s)/sq cm is obtained. If D is associated with the H I clouds to the Galactic center, an upper limit for the D/H ratio of 0.0043 is obtained for the clouds at V = 20 km/s and 50 km/s. If a significant fraction of the D exists in atomic form in molecular clouds, the upper limits are 1.2 x 10 to the -7th for the V = 20 km/s molecular cloud near the Galactic center and 8.3 x 10 to the -7th for the V = 50 km/s molecular cloud near the Galactic center. These results are consistent with the D observed in the Galactic center and the ISM being primarily cosmological in origin.
URI:	http://hdl.handle.net/2289/1391
ISSN:	0004-637X 1538-4357 (online)
Alternative Location:	http://adsabs.harvard.edu/cgi-bin/bib_query?1989ApJ...345..770L
Copyright:	(1989) by the American Astronomical Society. Scanned images provided by the NASA ADS Data System.
Appears in Collections:	Research Papers (A&A)

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