Investigation of ionization temperature as an explicit parameter in C3 models of nebulae
Presented by Ms. Andri PROZESKY on 9 Jul 2014 from 10:00 to 10:20
Type: Oral Presentation
Track: Track D1 - Astrophysics
The current capture-collision-cascade (C<sup>3</sup>) models of photoionized nebulae do not explicitly take into account the ionization temperature governing the level of ionization of species in the gas. I have calculated the departure coefficients for a hydrogen nebula using an ionization temperature instead of assuming that it is equal to the electron temperature. This is being done to investigate the known discrepancy that occurs in nebular abundance determinations that are derived from recombination lines and collisionally excited lines, respectively. Radiative transfer effects need to be dealt with differently in this model than when only the electron temperature is taken into account, for which a simple correction can be made for stimulated emission. Stimulated emission is of little importance for optical/IR lines but it can have a significant effect on the populations of radio recombination lines.
Prof DP Smits, email@example.com, Unisa