HR: 1400h
AN: SM23B-05    [Abstracts]
TI: Episodic Atmospheric Heating at Venus and Mars by Solar Storms
AU: * Brain, D A
EM: brain@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Mewaldt, R A
EM: rmewaldt@srl.caltech.edu
AF: Caltech, 220-47 Downs Laboratory, Pasadena, CA 91125, United States
AU: Cohen, C M
EM: cohen@srl.caltech.edu
AF: Caltech, 220-47 Downs Laboratory, Pasadena, CA 91125, United States
AU: Bougher, S W
EM: bougher@engin.umich.edu
AF: University of Michigan, Space Research Building 2455 Hayward Drive, Ann Arbor, MI 48109, United States
AU: Lillis, R J
EM: rlillis@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Luhmann, J G
EM: jgluhmann@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Delory, G T
EM: gdelory@ssl.berkeley.edu
AF: UC Berkeley Space Sciences Lab, 7 Gauss Way, Berkeley, CA 94720, United States
AU: Lammer, H
EM: helmut.lammer@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042, Austria
AU: Leblanc, F
EM: Francois.Leblanc@aerov.jussieu.fr
AF: Service d'aeronomie du CNRS, Reduit de Verrieres BP 3 Route des Gatines, Verrieres le Buisson, 91371, France
AB: The structure, dynamics, chemistry, and evolution of planetary atmospheres are in large part determined by the available sources of energy. One potentially important energy source is solar energetic particle (SEP) events consisting of large fluxes of charged particles accelerated near the Sun during and following fast coronal mass ejections. While other mechanisms provide more constant sources of energy, SEP events can significantly affect an atmosphere for short periods, possibly enhancing atmospheric loss and driving chemical reactions. At unmagnetized planets, in particular, SEPs of all energies have direct access to the atmosphere and so provide a more substantial energy source than at planets having protective global magnetic fields. Therefore quantification of the atmospheric energy input from SEP events is an important component of our understanding of the processes that control their state and evolution of planetary atmospheres. Here we present the results calculations of the energy input by a single large SEP event in the CO2 atmospheres of Venus and Mars. Using simplifying assumptions we calculate the penetration depth and energy deposition profile of energetic protons having different incident energies, and weight the profiles by the event-integrated energy spectrum of a SEP event to estimate the total energy deposition. We also use a more sophisticated radiation code (TRIM/HZETRN) to include the effects of secondary particles on the energy deposition profiles.
DE: 2101 Coronal mass ejections (7513)
DE: 2459 Planetary ionospheres (5435, 5729, 6026)
DE: 2479 Solar radiation and cosmic ray effects
DE: 5421 Interactions with particles and fields
DE: 7900 SPACE WEATHER
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly