Abstract
ABSTRACT regions of 21 relatively nearby galaxies, including two from the Local Group, are presented. These observations, made using the prime-focus nebular spectrograph and the Lallemand electronic camera attached to the coude spectrograph of the 120-inch (3-m) reflector, indicate: (1) Rapid nuclear rotation on a scale of 7-8 pc, as is observed in M 31 and M 32, does not occur in all galaxies. (2) Rapid central-region rotation (Vc_ max = 35-125 km s-1^ for 35 ≤ r ≤ 104 pc) occurs in six out of a sample of 14 "normal" (non-Seyfert) galaxies in the distance range from 2.5-46 Mpc. (3) Noncircular motions of the gas occur in all three of the Seyfert galaxies observed and in three of the five normal galaxies for which observations along the minor axis are available. (4) In at least five of the normal galaxies the motion of the interstellar gas differs from that of the stars. (5) In at least three of the normal galaxies different interstellar gas ions display different motions. (6) In four galaxies, the near-nuclear velocity slopes are found to be significantly larger than reported previously, generally from observations of lower resolution. The observations emphasize the fact that a substantial percentage of normal galaxies have noncircular gas motions and demonstrate that considerable care must be used in determining the rotational motions of galaxies from emission lines originating in the galaxian gas.
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