|Author||Haschick, A. D. ♦ Burke, B. F.|
|Source||United States Department of Energy Office of Scientific and Technical Information|
|Subject Keyword||Physics (Astrophysics & Cosmology)-Quasi-stellar, Radio & X-Ray Sources ♦ Physics (Astrophysics & Cosmology)-Galaxies ♦ Physics Research-Astrophysics & Cosmology-Quasi- Stellar, Radio & X-Ray Sources ♦ HYDROGEN- ABSORPTION SPECTRA ♦ QUASARS- RADIOWAVE RADIATION ♦ TEMPERATURE DEPENDENCE ♦ VELOCITY|
|Abstract||Radio spectra near 21 cm wavelength were taken of five close quasar- galaxy pairs. Neutral hydrogen absorption of radiation from the quasar 4C 32.33 (3C 232) has been detected at a velocity (C$delta$lambda/lambda$sub 0$) of 1418 km s$sup -1$. This feature lies 76 km s$sup -1$ away from the velocity of the galaxy NGC 3067 which is separated from the position of 4C 32.33 by less than 2 Holmberg radii. The absorption line has an optical depth, tau, of 0.027 +- 0.005 and a velocity half-width of < or = 5.5 km s$sup -1$. These parameters imply a neutral hydrogen column density less than or equal to 2.7 x 10$sup 17$ T/subs/ cm$sup -2$. No absorption features were detected in the sources 3C 268.4, 3C 275.1, 3C 309.1, or 3C 455. The similarity of the absorption feature in 4C 32.33 to that discovered by Brown and Roberts in 3C 286 lends some support to the suggestion by Brown and Roberts that the feature in 3C 286 is caused by a cloud of neutral hdyrogen associated with a galaxy somewhere along the line of sight to the quasar. (AIP)|
|Learning Resource Type||Article|
|Publisher Place||United States|
|Journal||Astrophys. J., Lett.|
|Organization||Department of Physics, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge|
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