[A-OS14] 陸域海洋相互作用ー惑星スケールの物質輸送

[AOS14-01] The Corona, Wind and Extreme Eruptive Events from Young Solar Analog, EK Dra: Observations, Models and Experiments

★Invited Papers

*Vladimir Airapetian¹、Meng Jin²、Junxiang Hu³、Kosuke Namekata¹、Kevin France⁴、Jackie Villadsen⁵、Kensei Kobayashi⁶ (1.NASA Goddard Space Flight Center、2.Lockheed Martin Solar and Astrophysics Laboratory、3.University of Alabama at Huntsville、4.University of Colorado at Boulder、5.Bucknell University、6.Yokohama National University)

キーワード：young solar analog, corona, wind, superflare, Coronal Mass Ejection, Stellar Energetic Particle event

The young (~50-300 Myr) rapidly rotating solar analogs show signatures of hot X-ray bright coronae, dense winds and frequent superflares with energy exceeding the largest solar flares by a factor of 10-1000 referred to as superflares. These space weather environments can severely affect habitable environments of exoplanets around thjem. Our recent observational campaigns of one of these stars, EK Dra (125 Myr), suggest that superflare events are associated with the ejection of fast and massive coronal magnetized materials referred to as coronal mass ejections (CMEs). We used the ZDI magnetograms in combination with reconstructed active regions from TESS and unpolarized Zeeman observations and HST/COS FUV line profiles to develop observationally constrained coronal and wind models of EK Dra using the 3D MHD Alfven Wave Solar Model (AWSoM). We then used simulated an energetic CME launched from the stellar corona, calculated the first shock and its evolution in the inner astrosphere. We the couple AWSoM code with iPATH kinetic code to model the initiation of stellar energetic particles accelerated via Diffusive Shock Acceleration mechanism. We describe the basic signatures and mechanisms of solar and stellar extremely powerful events and their impact on exoplanets around zero-age solar-like stars. I will discuss the implications of our recent theoretical simulations and laboratory experiments of impacts of eruptive events on the conditions required to find a prebiotic exoplanets around a solar-like stars and its pre-biosignatures.