Protostellar accretion bursts and their effect on pre-main-sequence stellar evolution
Abstract
The pre-main-sequence evolution of low-mass stars and brown dwarfs has been studied numerically by considering the accretion of mass onto the central object. Stellar evolution was computed using the STELLAR evolution code developed by Yorke & Bodenheimer. Mass accretion rates were taken from numerical hydrodynamics models of Vorobyov & Basu. We found that mass accretion can have a strong effect on the subsequent evolution of young stars and brown dwarfs. Accreting and non-accreting models disagree with each other, and the extent of the disagreement depends notably on the thermal efficiency of accretion. The largest mismatch is found for the cold accretion case. In the hot and hybrid accretion cases the disagreement between accreting and non-accreting models is less pronounced, but still remains noticeable for 1.0 M-yr-old objects. A wrong age estimate for objects of (sub-)solar mass is possible if isochrones based on non-accreting models are used.
- Publication:
-
Stars and their Variability Observed from Space
- Pub Date:
- 2020
- Bibcode:
- 2020svos.conf..363V
- Keywords:
-
- accretion;
- stars: formation;
- low-mass;
- brown dwarfs;
- pre-mainsequence