The time evolution of an ionization front
G. Tenorio-Tagle;
AaA, 1976, 53, 411

ABSTRACT:The evolutionary development of an ionization front (I-front) is investigated by carrying out a numerical computation that clearly shows all the particular features which link together the various types of I-fronts from the beginning to the end of their evolution under a realistic set of boundary conditions. The differential gasdynamic equations needed to construct dynamical models are solved numerically using a simultaneous iteration method for the plane-parallel case of an undisturbed gas, and the temporal evolution of a very fast but weak R-front is examined. The evolution is traced through the phases of a strong D-front, a critical D-front, and a weak D-front (the end of evolution). The results indicate that the shock, not the I-front, produces the main mechanical effect on the gas. A seven-stage evolutionary sequence is outlined.
KEYWORDS: gas ionization, hydrogen clouds, interstellar gas, shock fronts, astronomical models, equations of motion, gas dynamics, shock wave propagation, time dependence
PERSOKEY:region hii, ,
CODE: tenorio-tagle76