PS4.9PS4.9

The radiation and particle environment of G-, K-, and M-dwarf stars and their influence on (exo)planetary habitability 
Convener: Konstantin Herbst  | Co-conveners: John Lee Grenfell , Athanasios Papaioannou , Klaus Scherer 
Due to their large number within the Galaxy, their small radii, and closer-in habitable zones (HZ) G-, K- and M-dwarf stars are prime targets to detect habitable rocky (Earth-like) exoplanets. With upcoming missions such as the JWST, the E-ELT, PLATO as well as ESA’s most recently selected mission ARIEL, which, among others will be able to detect biosignatures (as an indicator for life) in exoplanetary atmospheres of planets orbiting distant stars, it is an opportune moment for theoretical background studies focusing on the particle- and radiation environment of Earth-like exoplanets in the HZ of G-, K-, and M-dwarf stars and their imprint on planetary habitability. However, although planets in the HZ of their host-stars could retain liquid water on their surface, its presence within the HZ is not the only requirement for life. This is because the presence of strong stellar winds, which can lead to the erosion of unprotected planetary atmospheres, and/or extreme stellar particle events as well as coronal mass ejections changes in the atmospheric chemistry as well as the atmospheric secondary particle environment may occur, and, therewith, may destroy atmospheric biosignatures and could prevent the creation and development of life. Thus, a detailed knowledge of the astrosphere as well as the astrospheric particle- and radiation environment is mandatory in order to study planetary habitability. Now is the time to make use of what we have learned from the Sun and our solar system to extend our knowledge to extrasolar planetary systems with potential Earth-like exoplanets in the HZs of G-, K- and M-dwarf stars.

The session brings together scientists from all fields of research that are related to solar, astrophysical and exoplanetary sciences. It will allow sharing of expertise amongst researchers working on different aspects of this interdisciplinary scientific field, allowing showcases of recent advancements in their field of specialization. The session aims to stimulate discussions about how individual disciplines can share their knowledge and benefit from each other.

We welcome contributions related but not limited to:

- Modeling stellar astrospheres and the corresponding energy-dependent CR flux
- Modeling the environment of close-in exoplanets around G-, K-, and M-dwarf stars, in particular modelling of mass-loss rates, angular momentum loss rates, the magnetic field configuration as well as the density and velocity of the stellar winds of G-, K- and M-dwarf stars
- Modeling stellar CMEs
- Evaluation and quantification of the solar UV-, X-ray, and energetic particle flux relationships and their extension to G-, K-, and M-dwarf stars
- The imprint of the stellar radiation field by modeling the magnetospheric transport and particle interactions within (exo)planetary atmospheres
- Atmospheric modeling studies of climate and (biosignature) photochemistry and the influence of stellar activity