
Models satisfying the above assumptions fit the observations of all four galaxies remarkably well. For all galaxies the rotation curves rule out isotropic velocity dispersion tensors. However, an excellent fit to the data can usually be obtained by including a measure of velocity anisotropy. Only in the case of NGC 4472 do the velocity dispersion profiles suggest that the radial and vertical dispersions are decoupled and thus the distribution function depends upon a third integral. In NGC 4278 the rotation velocity changes sign at R = 30 arcsec. Such behaviour is allowed by our models but since it is associated with a large isophote twist, it likely indicates a triaxial figure. We have developed a prolate model for NGC 4261 which accurately predicts the kinematics, although the comparison is limited to the RMS line-of-sight velocities.
We investigate how the predicted kinematics vary as a galaxy's
isophotes are varied from ``boxy'' to ``disky'' in shape merely by
deforming the bulge rather than introducing a thin disk. A disky model
rotates faster on the major axis than the equivalent boxy system, but
the effect is too small to account for Bender's (1988) suggested
correlation of (v/sigma)* with diskiness (which exhibits a large
scatter). In boxy galaxies the rotation velocity falls more slowly
away from the equatorial plane than in the equivalent disky galaxies.
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