2.3.3 MAXIMUM STREAMING MODELS
There is a special set of
self-consistent separable models in which the full variety of box orbits is
occupied, but only the thin tube orbits, i.e., those without any radial
epicyclic motion, are populated. Their distribution functions can be found
explicitly for separable models of arbitrary shapes and density profiles
(50,
87,
88,
108,
164,
165,
166,
167,
168,
326).
These models are hardly
realistic, but they are useful because they allow the explicit calculation of
the maximum possible stellar streaming velocities - and hence the maximum
possible angular momenta around the long- and the short axis - for any
separable triaxial model. This is important for the interpretation of the
observed velocity fields of elliptical galaxies, as it puts limits on the
amount of streaming for a given triaxial shape.