Line-driven ablation of circumstellar discs - II. Analysing the role of multiple resonances
Abstract
We extend our previous study of radiative ablation of circumstellar discs by line-scattering of the star's radiation, accounting now for the effect of multiple line resonances off the stellar limb. For an analytic, three-dimensional model of the velocity structure of an equatorial Keplerian disc bounded at higher latitudes by a radially accelerating stellar wind outflow, we use root-finding methods to identify multiple resonances from a near-disc circumstellar location along starward rays both on and off the stellar core. Compared to our previous study that accounted only for the effect of on-core resonances in reducing the radiative driving through the scattering of radiation away from a near-disc circumstellar location, including off-limb resonances leads to additional radiative driving from scattering towards this location. Instead of the up to 50 per cent reduction in line-acceleration previously inferred from multiple resonance effects, we now find a more modest 15-20 per cent net reduction.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- February 2018
- DOI:
- 10.1093/mnras/stx2772
- arXiv:
- arXiv:1710.09312
- Bibcode:
- 2018MNRAS.474..847K
- Keywords:
-
- circumstellar matter;
- stars: massive;
- stars: winds;
- outflows;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 8 pages, 6 figures