Location of the centers of Giant Anticyclons relative to spiral arms,
as it depends on the sign of kappa^2 (square of the epicyclic frequency) and
on which force is predominant in the gaseous disk:
hydrodynamic pressure, self-gravity or external forces

Character of description
of the gaseous disk

kappa^2>0

kappa^2<0

Hydrodynamics

In Spiral

Self-gravitation

Between spiral

Boundary of gravitational
stability

Between spiral

External non-axially
symmetric gravitational
potential

Center of vortices
may be shifted relative
to density exterema

Center of vortices
may be shifted relative
to density exterema