Improvements on radiative acceleration calculations in stellar envelopes

Details Improvements on radiative acceleration calculations in stellar envelopes Improvements on radiative acceleration calculations in stellar envelopes

May 1995

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995a%26a...297..223g&link_type=abstract

Astronomy and Astrophysics (ISSN 0004-6361), vol. 297, no. 1, p. 223-236

Astronomy and Astrophysics

Astrophysics

56

Line Spectra, Opacity, Radiative Transfer, Stellar Atmospheres, Stellar Atmospheres, Stellar Envelopes, Atmospheric Diffusion, Atmospheric Models, Carbon, Iron, Photoionization, Radiant Flux Density, Stellar Models, Stellar Spectra

Scientific paper

The various processes that need to be included in calculations of radiative acceleration in stellar envelopes are presented and their importance is evaluated. The general procedure used to compute radiative accelerations and the usual approximations are recalled, together with a summary of the useful equations. Major improvements are obtained by using the newly available atomic data provided by the OPACITY project (OP). They first allow to compute the frequency dependence of the background opacity and to improve the evaluation of the collisional line broadening. The contributions of bound-bound and bound-free transitions to the radiative acceleration are then calculated for each ion of a given element. A method of averaging among ions is developed to obtain the net acceleration on the element, in a simple model taking into account the effects of rapid reactions between ions. Examples of results are given for carbon and iron in a model-envelope with Teff = 8000 K, log g = 4.2, Z = 0.02. They differ significantly from previous calculations. The effects of different improvements are discussed.

Affiliated with

Also associated with

No associations

Rating

Improvements on radiative acceleration calculations in stellar envelopes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Improvements on radiative acceleration calculations in stellar envelopes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Improvements on radiative acceleration calculations in stellar envelopes will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1055902