An Optical, Near-Infrared, and Kinematic Study of Four Early-Type Resonance Ring Galaxies

Abstract

We present optical and near-infrared surface photometry of four early-type galaxies considered to have resonance ring phenomena on the basis of morphology. We also present kinematics and rotation curves for three of the galaxies. The four galaxies are exceptional examples of resonance ring galaxies, and from these observations we derive the characteristic light distributions, the colors of the rings, and the near-infrared disk mass-to-light ratios. We also deproject the galaxies to examine intrinsic ring shapes and bar/ring alignments. From models of the rotation curves, we compute the Lindblad precession frequencies to examine resonance locations in the disks of the galaxies. Under the assumption that the outer rings and pseudorings seen in these galaxies are linked to the outer Lindblad resonance, we find that the inner rings of the sample galaxies lie near the inner 4:1 resonance and that the sharp ends of the bars lie on average at only 0.65 times the predicted radius of corotation.