Stellar Orbital Studies in Normal Spiral Galaxies II: Restrictions to
  Structural and Dynamical parameters on Spiral Arms
  Making use of a set of detailed potential models for normal spiral galaxies,
we analyze the disk stellar orbital dynamics as the structural and dynamical
parameters of the spiral arms (mass, pattern speed and pitch angle) are
gradually modified. With this comprehensive study of ordered and chaotic
behavior, we constructed an assemblage of orbitally supported galactic models
and plausible parameters for orbitally self-consistent spiral arms models. We
find that, to maintain orbital support for the spiral arms, the spiral arm
mass, M$_{sp}$, must decrease with the increase of the pitch angle, $i$; if $i$
is smaller than $\sim10\deg$, M$_{sp}$ can be as large as $\sim7\%$, $\sim6\%$,
$\sim5\%$ of the disk mass, for Sa, Sb, and Sc galaxies, respectively. If $i$
increases up to $\sim25\deg$, the maximum M$_{sp}$ is $\sim1\%$ of the disk
mass independently in this case of morphological type. For values larger than
these limits, spiral arms would likely act as transient features. Regarding the
limits posed by extreme chaotic behavior, we find a strong restriction on the
maximum plausible values of spiral arms parameters on disk galaxies beyond
which, chaotic behavior becomes pervasive. We find that for $i$ smaller than
$\sim20\deg$, $\sim25\deg$, $\sim30\deg$, for Sa, Sb, and Sc galaxies,
respectively, M$_{sp}$ can go up to $\sim10\%$, of the mass of the disk. If the
corresponding $i$ is around $\sim40\deg$, $\sim45\deg$, $\sim50\deg$, M$_{sp}$
is $\sim1\%$, $\sim2\%$, $\sim3\%$ of the mass of the disk. Beyond these
values, chaos dominates phase space, destroying the main periodic and the
neighboring quasi-periodic orbits.
