The beta Pictoris circumstellar disk. X. Numerical simulations of infalling evaporating bodies.
Abstract
The temporal variations in some metallic absorption lines of Beta Pic's spectrum had been already interpreted as the result of the infall of small evaporating cometary-like bodies onto the star. To check this scenario, a model of such an evaporation has been developed, and subsequent numerical simulations have been carried out. This theoretical work has highlighted that the suggested scenario reproduces fairly well the observations, even the drastic difference between the behavior of Ca II lines on the one hand, and Al III and Mg II ones on the other hand, which is mainly due to radiation pressure acting differently on these ions. Assumptions on the evaporation's characteristics and, especially, on the orbits followed by the infalling bodies have been deduced from the simulation. These geometrical results suggest that the infalling objects may come into the star's vicinity from a precise direction. These rather frequent infalls could be then interpreted as the result of the perturbing action of an eventual planetary or protoplanetary body present in the disk on a large amount of small passing-by bodies.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- September 1990
- Bibcode:
- 1990A&A...236..202B
- Keywords:
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- Comets;
- Computational Astrophysics;
- Evaporation;
- Metal Ions;
- Stellar Envelopes;
- Absorption Spectra;
- Computerized Simulation;
- Line Spectra;
- Two Dimensional Models;
- Astrophysics