Gas Disks and Supermassive Black Holes in Nearby Radio Galaxies

the gas exhibits a regular rotation profile. The fit to the central spectrum is improved
by the addition of a broad component. Data for this galaxy are shown in Figure 3.22
(see key in Figure 3.1 for an explanation of these plots).
3.5 Interpretation and Discussion
In our initial interpretation we have focussed on understanding the general parameters
of the data set. We will undertake more detailed analyses in future work that we
outline in §6 below. Here, we first describe the categorization of sources as rotating
and non-rotating systems based on the observed kinematics (§5.1). We then discuss
the ionization states of the nuclear regions (§5.2). We go on to discuss the presence
of broad components in these nuclei and a more detailed analysis of the line shapes
(§5.3).
3.5.1 Rotators and non-rotators
By inspecting maps of the central kinematics and the velocity profiles along each slit
(as presented above in figures 3.2 to 3.22), we have classified, by eye, the galaxies
into two classes: rotators and non-rotators. Rotators are systems where we see pat-
terns reminiscent of rotation curves; in non-rotators we find no such patterns - the
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