Models of cuspy triaxial stellar systems. III: The effect of velocity
  anisotropy on chaoticity
  In several previous investigations we presented models of triaxial stellar
systems, both cuspy and non cuspy, that were highly stable and harboured large
fractions of chaotic orbits. All our models had been obtained through cold
collapses of initially spherical $N$--body systems, a method that necessarily
results in models with strongly radial velocity distributions. Here we
investigate a different method that was reported to yield cuspy triaxial models
with virtually no chaos. We show that such result was probably due to the use
of an inadequate chaos detection technique and that, in fact, models with
significant fractions of chaotic orbits result also from that method. Besides,
starting with one of the models from the first paper in this series, we
obtained three different models by rendering its velocity distribution much
less radially biased (i.e., more isotropic) and by modifying its axial ratios
through adiabatic compression. All three models yielded much higher fractions
of regular orbits than most of those from our previous work. We conclude that
it is possible to obtain stable cuspy triaxial models of stellar systems whose
velocity distribution is more isotropic than that of the models obtained from
cold collapses. Those models still harbour large fractions of chaotic orbits
and, although it is difficult to compare the results from different models, we
can tentatively conclude that chaoticity is reduced by velocity isotropy.
