P12A-07
Solar Energetic Particle Events Observed by MAVEN
Monday, 14 December 2015: 11:50
3002 (Moscone West)
Christina O Lee1, Davin E Larson1, Robert J Lillis2, Janet G Luhmann2, Jasper S Halekas3,4, David Brain5, John E P Connerney6, Jared R Espley6, Francis Epavier5, Ed Thiemann7, Cary Zeitlin8 and Bruce Martin Jakosky7, (1)Space Sciences Laboratory, Berkeley, CA, United States, (2)University of California Berkeley, Berkeley, CA, United States, (3)University of Iowa, Iowa City, IA, United States, (4)University of Iowa, Physics and Astronomy, Iowa City, IA, United States, (5)LASP, University of Colorado at Boulder, Boulder, CO, United States, (6)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (7)Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, (8)NASA Johnson Space Center, Houston, TX, United States
Abstract:
We present observations of solar energetic particle (SEP) events made by the Mars Atmosphere and Volatile EvolutioN (MAVEN) SEP instrument, which measures energetic ions and electrons impacting the upper Martian atmosphere. Since the arrival of the MAVEN spacecraft at Mars, a large number of solar flares and a few major coronal mass ejections (CMEs) erupted from the Sun. The SEPs are accelerated by the related shock in the solar corona or by the propagating interplanetary shock ahead of the CME ejecta. Mixed in with these SEPs are particles accelerated by the shocks of corotating streams, some of which have recurred for several solar cycles due to the persistent coronal hole sources. The SEP events are analyzed together with the upstream solar wind observations from the MAVEN Solar Wind Ion Analyzer (SWIA) and magnetometer (MAG). The sources of the SEP events are determined from Earth-based solar imagery and the MAVEN Extreme Ultra-violet Monitor (EUVM) together with numerical simulations of the inner heliospheric conditions. A comparison with the radiation dose rate measurements from the Mars Science Laboratory (MSL) Radiation Assessment Detector (RAD) reveals a lack of ground signatures during the onset of the highest energy SEPs for the events observed by MAVEN, indicating that the SEPs fully deposit their energies into the Martian atmosphere. Using measurements made from the ensemble of instruments onboard MAVEN, we investigate the consequences of SEPs at Mars for a number of events observed during the primary science mapping phase of the MAVEN mission.
