Central Rotation Curves of Spiral Galaxies

We present high-resolution central-to-outer rotation curves for Sb, SBb, Sc,and SBc galaxies. We discuss their general characteristics, particularly theircentral behavior, as well as dependencies on morphological types, activity, andpeculiarity. The rotation curves generally show a steep nuclear rise, andhigh-velocity central rotation, followed by a broad maximum in the disk andthen by a flat rotation due to the massive halo. Since the central highvelocity and steep rise are common to all massive galaxies, it cannot be due tonon-circular motions. Disk rotation curves of barred galaxies show largerdispersion than those of normal galaxies which is probably due to non-circularmotions. Interacting galaxies show often perturbed outer rotation curves, whiletheir central rotation shows no particular peculiarity. Also, centralactivities, such as starbursts and AGN, appear to show no particularcorrelation with the property of rotation curves. This would suggest that thecentral activities are triggered by a more local effect than the globaldynamical property.Comment: Latex 13 pages + Postscript figures (Fig.1 to Fig. 9, and Appendix Fig 1a (6 pages)). ApJ in pres