[P-AE16] Exoplanets

[PAE16-04] Search for Extra-terrestrial Mother Planets Catalogue for influence of stellar activities on the extraplanetary system.

*Yosuke Alexandre Yamashiki¹, Hiroyuki Maehara², Vladimir Airapetian³, Yuta Notsu⁶, Kosuke Namekata⁴, Riko Shimizu⁵, Nami Kimura¹, Tatsuhiko Sato⁷, Takanori Sasaki⁴ (1.Earth & Planetary Water Resources Assessment Laboratory Graduate School of Advanced Integrated Studies in Human Survivability Kyoto University, 2.National Astronomical Observatory of Japan, 3.NASA's Goddard Space Flight Center, 4.Graduate School of Science, Kyoto University, 5.Faculty of Science, Kyoto University, 6.University of Colorado, 7.Japan Atomic Energy Agency)

Keywords:extrasolar planetary catalogue, Stellar Energetic Particles, Mother planet

The Search for Extra-terrestrial Mother Planets Catalogue will be used to search for potentially habitable mother planets and to derive data on stellar activity of their host stars. The ultimate goal of the survey is to accomplish creating a full and original data catalogue of exoplanets at Kyoto University, based on the Exokyoto catalogue, while paying special attention to characterization of stellar activity of planet hosts. We presented the first quantitative impact evaluation system of stellar flares on the habitability factors with an emphasis on the impact of stellar proton events. We derive the maximum flare energy from stellar star spot sizes and examine the impacts of flare-associated ionizing radiation on CO₂, H₂, and N₂+ O₂-rich atmospheres of a number of well-characterized terrestrial type exoplanets. Our simulations based on the Particle and Heavy Ion Transport code System suggest that the estimated ground-level dose for each planet in the case of terrestrial-level atmospheric pressure (1 bar) for each exoplanet does not exceed the critical dose for complex (multicellular) life to persist, even for the planetary surface of Proxima Centauri b, Ross-128 b, and TRAPPIST-1 e. We re-conduct numerical simulation based on newely obtained spectra for the possible CME occurred in those planetary system, revailing higher and harder spectra may induce significant damage even for those "habitable"planets. Some thick atmosphere and hydrosphere may protect their habitability reducing exposure impact for those planet. Together with the observation for H-alpha for host stars we also are attempt to conduct developing database for those risk for potentially habitable planetary system.
In this presentation we will introduce how the energy spectra of potential CME may affect entire estimation of the possible dose at the surface environment of extrasolar planets with preliminary classification by stellar impact among "habitable" planets situated CHZ based on the conventional classification theory. According to our estimation, some planets with hardest energy spectra and higher atmospheric escape rate the surface environment become severe for terrestrial-type life system.