Frequency of Gas-Stellar Counterrotation

Abstract

We search for bulk counterrotation of the gas and stars in 67 galaxies of all types and a wide range of luminosities. Bulk counterrotation characterizes \~25-30% of E/S0's with extended gas, but at most a few percent of Sa-Sbc spirals. For S0's, the frequency of counterrotation we derive agrees with previous work, but we sample significantly fainter luminosities. Thus the agreement suggests that similar formation mechanisms may operate over a wide range of physical scales.