An Estimate of the Gas Inflow Rate Along the Bar in NGC 7479

Abstract

We present images of the barred galaxy NGC 7479 in the optical and near infrared broad--bands $B,V,R,J,H,K$, and images in H$α$+[N II] and CO(J=1$\rightarrow$0) emission. The H$α$ and CO emission in the bar are coincident and confined to narrow linear features that are offset from the center of the bar as observed in the near infrared. We estimate the gravitational potential from the $K$ image, which provides an estimate of the torque on the gas at the position of the CO emission in the bar. We find that the implied gas inflow velocity derived from the torque is $10-20$ km s$^{-1}$. Our inflow velocity is independent of the large streaming motions which can be observed in CO and HI.

16pages, postscript, ~accepted to ApJ, Paper is available with compressed postscript figures via anonymous ftp from payne.mps.ohio-state.edu in the directory pub/quillen/n7479, AYOSU-9-94-002