IWF/ÖAW

Main task

Upper atmospheres (and magnetospheres) in the context of solar/stellar wind plasma and radiation interaction

Main research topics

1. Upper atmosphere response to solar/stellar activity

Monte Carlo & test-particle upper atmosphere and SW-plasma interaction codes → atmosphere evolution, exoplanets

2. Exoplanet Magnetospheres

Structure, topology, and dynamics of exoplanetary magnetospheres

Refereed publications (since Jan 2013)

Total: 15 (first author: 11)

Educational activities (since Jan 2013)

PhD thesis: 1; Master theses: 2

Lecturing at University of Graz

Upper Atmosphere Physics

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IWF/ÖAW

Lead: Helmut Lammer

Members Staff: O. Archipov, M. L. Khodachenko, K. G. Kislyakova,

H.I.M. Lichtenegger, M. Pfleger, J. Sasunov Students: PhD: P. Odert; Master: I. Juvan, S.-C. Schiefer

Cooperation within IWF Atmosphere response to solar activity (Baur et al.) Solar/stellar winds/radio signals & exoplanets (Fischer et al.) Solar wind and magnetospheric interaction studies (Nakamura et al.) Heliospheric physics (Narita et al.) CoRoT/Cheops: exoplanet characterization (Steller et al.)

Key external collaboration

Austria: IfA, Univ. Vienna; Germany: DLR; Sweden: IRF; Finland: FMI; Belgium: University of Leuven; Spain: Univ. de les Illes Balears; Russia: ICM/RAS Krasnoyarsk, INASAN Moscow, Inst. of Laser Phys./RAS, Moscow State Univ.

Who are we?

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IWF/ÖAW

Extreme solar events → young Sun/stars

Thermosphere density response GRACE

Correlation with solar proxies

Upper atmosphere impact of super-flares

Photochemical processes → suprathermal “hot” atoms (H, O, C, N)

Monte Carlo modeling of energetic neutral atoms (ENAs) and exosphere formation and escape

Model validation: VEX, MEX, Earth obs.

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Upper Atmosphere Physics

[Gröller et al., PSS, 2014]

IWF/ÖAW 4

Surface Sputtering / Stellar Dynamics

Surface sputtering → airless bodies

Plasma surface interaction

Particle release from surfaces due to solar radiation and plasma

Precursor studies: BepiColombo, JUICE

Kepler stars photometry → deep mixing

Variation of 513 stellar LC spectral harmonics

Time scale 1 of the first rotational

harmonic ~ theoretical turnover time MLT of deep mixing

Remote probing of stellar deep convection

IWF/ÖAW 4

1

MLT

Callisto: sputtered O exosphere

IWF/ÖAW

Escape of nebula-based or degassed protoatmospheres from early Solar System planets and “super-Earths” (exoplanets)

Hydro-code development

ThermosphereEUV heating

Atmosphereexpansion

Thermal escape of H, O, C

Dragging of O, C, N, CO2, etc.

Effect on density,radius-mass

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Atmosphere Evolution

[Rauer et al., Exp. Astron., 2014] [Lammer et al., MNRAS, 2014]

Mars-size planetaryembryo at 1 AU

Characterization of exoplanet exosphere-magnetosphere environments by UV observations and hydrogen cloud, stellar radiation and plasma interaction modeling

Hydrogen coronaemodeling

ENA heatingfeedback studies

Plasma interaction & ion escape

Space weathereffect studies

HST UV spectrareproduction

IWF/ÖAW 6

Exoplanet Environments

[Kislyakova et al., A&A, 2014] [Kislyakova et al., Astrobiol., 2013]

IWF/ÖAW

MHD simulations of the flow-driven magnetodisk formation

No or weak rotation case:

Stellar XUV atm. heating & expansion deformation of dipole field

inner region locked plasma thin disk region

plasma follows field lines

Experimental confirmation of the flow-driven magnetodisk formation

typical topology of magnetic field

electric current sheet in the equatorial plane

Exoplanet Magnetospheres

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IWF/ÖAW

Solar/stellar plasma dynamics: Solar Orbiter Tachocline, photosphere, chromosphere, corona

Upper atmosphere solar activity response: MEX, VEX, LEOs, etc.

Hot C, O, N & H atom escape from Venus, Earth, Mars, exoplanets

Model validation on solar event (CMEs) studies at Earth’s thermosphere

Solar activity & plasma response on Mercury’s and Jovian satellite surfaces: BepiColombo, JUICE

EUV, CME & plasma related particle release and exosphere formation

Origin & evolution of atmospheres, exoplanets: CoRoT, CHEOPS

Protoatmosphere escape studies (sub- to super-Earths) Upper atmosphere structure, radiation & particle heating Stellar plasma electrodynamics/exoplanet and exo-

magnetosphere hypotheses tests via Lyman-α diagnostic

Future Plans: 2015-2018

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IWF/ÖAW

Thank you

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