The gas dynamics of H II regions. II - Two-dimensional axisymmetric calculations
P. Bodenheimer, B. Tenorio-Tagle, H. W. Yorke;
ApJ, 1979, 233, 85
ABSTRACT:Hydrodynamic numerical calculations of the evolution of H II regions in dense molecular clouds
are extended to two space dimensions with axial symmetry.
Specific
problems are treated which emphasize the behavior of flows that cross a
discontinuity between a cloud and the low-density intercloud medium.
Calculations
are performed for four cases, including two involving 'champagne flows':
(1) the edge of the cloud is overrun by a supersonic ionization front; (2)
the initial Stromgren sphere surrounding the star lies deep inside the
cloud, so that the cloud's edge is ionized by a subsonic ionization front; (3)
the ionization front breaks through two opposite faces of the same cloud
simultaneously; and (4) the flow encounters an isolated globule with a density of 1000
particles/cu cm shortly after emerging from the molecular cloud.
The results are
compared with observations of various interstellar clouds.
KEYWORDS: astronomical models, gas dynamics, h ii regions, interstellar matter, nebulae, stellar evolution, gas ionization, graphs (charts), hydrodynamic equations, hydrodynamics, mathematical models, tables (data)
PERSOKEY:region hii, ,
CODE: bodenheimer79