Near-infrared observations of a nuclear bar and biconical structure in the starburst galaxy NGC 6946

We use high-resolution near-infrared (J- and K-band) images of the nuclear starburst galaxy NGC 6946 to compare stellar morphology with the previously published distribution of CO in the central regions. We find a small stellar bar with a length of 210 pc, which lies perpendicular to an 1860 pc long stellar oval distortion. The small bar has a position angle of 140 degrees, which coincides with a barlike feature in CO, as well as with the kinematic minor axis. It has a flat light distribution and a strong bar-interbar contrast of 1 mag; it may play a role in fueling the central starburst despite its small size. A biconical structure about 80 pc long, perpendicular to the bar, is evident in the (J-K) color map. The (J-K) contours match published high-resolution CO contours very well.