SIMBAD references

2017MNRAS.470.4026V - Mon. Not. R. Astron. Soc., 470, 4026-4033 (2017/October-1)

Exoplanets as probes of the winds of host stars: the case of the M dwarf GJ 436.


Abstract (from CDS):

Winds of cool dwarfs are difficult to observe, with only a few M dwarfs presenting observationally derived mass-loss rates ({dot}M), which span several orders of magnitude. Close-in exoplanets are conveniently positioned in the inner regions of stellar winds and can, thus, be used to probe the otherwise-unobservable local properties of their host-stars' winds. Here, we use local stellar wind characteristics observationally derived in the studies of atmospheric evaporation of the warm-neptune GJ 436b to derive the global characteristics of the wind of its M-dwarf host. Using an isothermal wind model, we constrain the stellar wind temperature to be in the range (0.36-0.43) MK, with {dot}M=(0.5-2.5) ×10–15   M  yr–1. By computing the pressure balance between the stellar wind and the interstellar medium, we derive the size of the astrophere of GJ 436 to be around 25 au, significantly more compact than the heliosphere. We demonstrate in this paper that transmission spectroscopy, coupled to planetary atmospheric evaporation and stellar wind models, can be a useful tool for constraining the large-scale wind structure of planet-hosting stars. Extending our approach to future planetary systems discoveries will open new perspectives for the combined characterization of planetary exospheres and winds of cool dwarf stars.

Abstract Copyright: © 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): stars: individual: GJ 436 - stars: low-mass - stars: winds, outflows - planetary systems - planetary systems

Simbad objects: 13

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2017MNRAS.470.4026V and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact