Accession Number : AD0754079

Title :   327 MHz Observations of the Galactic Center: Possible Detection of a Deuterium Absorption Line,

Corporate Author : OWENS VALLEY RADIO OBSERVATORY PASADENA CALIF

Personal Author(s) : Cesarsky,Diego A. ; Moffet,Alan T. ; Pasachoff,Jay M.

Report Date : 1972

Pagination or Media Count : 18

Abstract : The authors observed the spectrum of radiation from the spectrum of radiation from the galactic center in the vicinity of the deuterium ground-state hyperfine transition. With about 100 hours of observing time the spectrum shows r.m.s. fluctuations about 7x10 to the minus 5th power of the on-source power level. An absorption feature at 327.38837 plus or minus 00001 MHz (corrected to the local standard of rest) has a depth of 2x10 to the minus 4th power of the continuum level. This feature is probably the deuterium line at v(LSR)+ -3.7 km/s. A discussion is included of the abundance of interstellar deuterium relative to hydrogen and of the difficulties in calculating it. Uncertainties include the optical depth of the corresponding hydrogen absorption line, which is saturated, and the distribution of absorbing clouds. (Author)

Descriptors :   (*EXTRATERRESTRIAL RADIO WAVES, GALAXIES), (*INTERSTELLAR MATTER, DEUTERIUM), RADIO ASTRONOMY

Subject Categories : Astrophysics

Distribution Statement : APPROVED FOR PUBLIC RELEASE