Influence of stellar X-ray luminosity distribution and its evolution on exoplanetary mass loss - AstrophysicsReportar como inadecuado




Influence of stellar X-ray luminosity distribution and its evolution on exoplanetary mass loss - Astrophysics - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: Aims: We investigate the influence of high-energy stellar radiation atclose-in orbits on atmospheric mass loss during stellar evolution of a G-typestar. Methods: High-energy stellar luminosity varies over a wide range for Gfield stars. The temporal evolution of the distribution of stellar X-rayluminosity and its influence on the evolution of close-in exoplanets isinvestigated. X-ray luminosity distributions from the Pleiades, the Hyades andthe field are used to derive a scaling law for the evolution of the stellarX-ray luminosity distribution. A modified energy-limited escape approach isused to calculate atmospheric mass loss for a broad range of planetaryparameters. Results: We show that the evolution of close-in exoplanets stronglydepends on the detailed X-ray luminosity history of their host stars, whichvaries over several orders-of-magnitude for G stars. Stars located at thehigh-energy tail of the luminosity distribution can evaporate most of itsplanets within 0.5 AU, while for a moderate luminosity a significant fractionof planets can survive. We show the change on an initial planetary massdistribution caused by atmospheric escape.



Autor: T. Penz, G. Micela, H. Lammer

Fuente: https://arxiv.org/







Documentos relacionados