# Evolution of very low mass pre-main sequence stars and young brown dwarfs under accretion: A phenomenological approach - Astrophysics

Evolution of very low mass pre-main sequence stars and young brown dwarfs under accretion: A phenomenological approach - Astrophysics - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: In the poster presented in Cool Star 15, we analyzed the effect of diskaccretion on the evolution of very low mass pre-main sequence stars and youngbrown dwarfs and the resulting uncertainties on the determination of masses andages. We use the Lyon evolutionary 1-D code assuming a magnetospheric accretionprocess, i.e., the material falls covering a small area of the radiativesurface, and we take into account the internal energy added from the accretedmaterial as a free parameter $\epsilon$. Even if the approach to this problemis phenomenological, our formalism provides important hints aboutcharacteristics of disk accretion, which are useful for improved stellarinterior calculations. Using the accretion rates derived from observations ourresults show that accretion does not affect considerably the position oftheoretical isochrones as well as the luminosity compared with standardnon-accreting models. See more discussions in a forthcoming paper by Gallardo,Baraffe and Chabrier 2008.

Autor: Jose Gallardo Universidad de Chile, Chile, Isabelle Baraffe CRAL, France, Gilles Chabrier CRAL, France

Fuente: https://arxiv.org/