H I absorption in radio elliptical galaxies - Evidence for infall

Abstract

view Abstract Citations (203) References (52) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS H I Absorption in Radio Elliptical Galaxies---Evidence for Infall van Gorkom, J. H. ; Knapp, G. R. ; Ekers, R. D. ; Ekers, D. D. ; Laing, R. A. ; Polk, K. S. Abstract A complete sample of 29 radio galaxies with compact cores has been observed by the VLA in the H I line to an almost uniform optical-depth sensitivity of τ ~0.01 at a velocity resolution of 40 km s^-1^. These galaxies were selected using continuum observations of an almost complete sample of 49 radio galaxies; 21 cm core flux densities are given for these galaxies. H I absorption was detected in four galaxies, NGC 3894, NGC 5363, 3C 236, and 4C 31.06, bringing to eight the number of radio ellipticals in which H I absorption has been detected. In all cases, absorption is seen redshifted with respect to the galaxy's systemic velocity, or close to the systemic velocity, or both. No blueshifted absorption components are seen. These observations demonstrate the infall of H I to the inner regions of radio elliptical galaxies. The estimated infall rates (a few hundredths of a solar mass per year) are more than adequate to fuel the nuclear activity. Publication: The Astronomical Journal Pub Date: March 1989 DOI: 10.1086/115016 Bibcode: 1989AJ.....97..708V Keywords: Absorption Spectra; Elliptical Galaxies; H Lines; Radio Galaxies; Active Galactic Nuclei; Continuous Radiation; Flux Density; Luminosity; Red Shift; Very Large Array (Vla); Astrophysics; RADIO SOURCES: GALAXIES; GALAXIES: INTERGALACTIC MEDIUM full text sources ADS | data products SIMBAD (66) NED (66)