We present new velocity dispersion measurements of a sample of 12 spiral galaxies for which extended rotation curves are available. These data are used to refine a recently discovered correlation between the circular velocity and the central velocity dispersion of spiral galaxies. We find a slightly steeper slope for our larger sample, confirm the negligible intrinsic scatter on this correlation and find a striking agreement with the corresponding relation for elliptical galaxies. We combine this correlation with the well‐known MBH–σ relation to obtain a tight correlation between the circular velocities of galaxies and the masses of the supermassive black holes they host. This correlation is the observational evidence for an intimate link between dark matter haloes and supermassive black holes. Apart from being an important ingredient for theoretical models of galaxy formation and evolution, the relation between MBH and circular velocity can serve as a practical tool to estimate black hole masses in spiral galaxies.

We present deep single-dish H i observations of a sample of six nearby E+A galaxies (0:05 < z < 0:1). A nonnegligible fraction of a local sample of E+As are detected in H i. In four galaxies, we have detected up to a few times 10 9 M of neutral gas. These E+A galaxies are almost as gas-rich as spiral galaxies with comparable luminosities. There appears to exist no direct correlation between the amount of H i present in an E+A galaxy and its star formation rate as traced by radio continuum emission. Moreover, the end of the starburst does not necessarily require the complete exhaustion of the neutral gas reservoir. Most likely, an intense burst of star formation consumed the dense molecular clouds, which are the sites of massive star formation. This effectively stops star formation, even though copious amounts of diffuse neutral gas remain. The remaining H i reservoir may eventually lead to further episodes of star formation. This may indicate that some E+As are observed in the inactive phase of the star formation duty cycle.

Abstract. We discuss the kinematical structure of a two-parameter family of isotropic models with a central black hole. The family contains the slope of the central density cusp and the relative black hole mass as parameters. Most of the basic kinematical quantities of these models can be expressed analytically. This family contains three distinct models where also the distribution function, differential energy distribution and spatial LOSVDs can be expressed completely analytically. Each of these models shows a drastically different behaviour of the distribution function. Although the effect of a black hole on the distribution function is very strong, in particular for models with a shallow density cusp, the differential energy distribution is only marginally affected. We discuss in detail the effects of a central black hole on the LOSVDs. The projected velocity dispersion increases with black hole mass at small projected radii, but the effect of a black hole on the shape of the LOSVDs (characterized by the h 4 parameter) is less straightforward to interpret. Too much reliance on the wings of the LOSVDs and the value of the h 4 parameter to determine black hole masses might hence be dangerous.

FCC046 is a Fornax Cluster dwarf elliptical galaxy. Optical observations have shown that this galaxy, besides an old and metal-poor stellar population, also contains a very young centrally concentrated population and is actively forming stars, albeit at a very low level.Here, we report on 21 cm observations of FCC046 with the Australia Telescope Compact Array (ATCA) which we conducted in the course of a small survey of Fornax Cluster early-type dwarf galaxies. We have discovered a ∼ 10 7 M ⊙ Hi cloud surrounding FCC046. We show that the presence of this significant gas reservoir offers a concise explanation for this galaxy's optical morphological and kinematical properties.Surprisingly, the Hi gas, as evidenced by its morphology and its rotational motion around the galaxy's optical major axis, is kinematically decoupled from the galaxy's stellar body. This is the first time such a ring of gaseous material in minor-axis rotation is discovered around a dwarf galaxy.

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