Molecular Gas in 3C 293: The First Detection of CO Emission and Absorption in a Fanaroff‐Riley Type II Radio Galaxy

The first detection of CO emission in a Fanaroff-Riley Class II (i.e.,edge-brightened radio morphology) radio galaxy is presented. Multi- wavelength(0.36-2.17 micron) imaging of 3C 293 shows it to be a disk galaxy with anoptical jet or tidal tail extending towards what appears to be a companiongalaxy 28 kpc away via a low surface brightness envelope. The molecular gasappears to be distributed in an asymmetric disk rotating around an unresolvedcontinuum source, which is presumably emission from the AGN. A narrow (approx60 km/s) absorption feature is also observed in the CO spectrum and iscoincident with the continuum source. Using the standard CO conversion factor,the molecular gas mass is calculated to be 1.5x10^10 M_sun, several times themolecular gas mass of the Milky Way. The high concentration of molecular gaswithin the central 3 kpc of 3C 293, combined with the multiwavelengthmorphological peculiarities, support the idea that the radio activity has beentriggered by a gas-rich galaxy-galaxy interaction or merger event.Comment: LaTex, 8 pages with 2 postscript and 2 jpg figures, ApJ, in pres