Solar energetic particle events observed by MAVEN
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 several coronal mass ejections (CMEs) have 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 rotations due to the persistent coronal hole sources of high speed solar wind. 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 the numerical Wang-Sheeley-Arge (WSA)-Enlil simulations of the heliospheric conditions. A comparison with the radiation dose rates measured by the Mars Science Laboratory (MSL) Radiation Assessment Detector (RAD) reveals a lack of detectable ground signatures during the onset of the highest energy SEPs for the events observed by MAVEN, indicating that the SEPs fully deposit their energy in the Martian atmosphere. We will discuss the consequences of SEPs at Mars for a number of events observed over the course of the MAVEN mission.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.P13A1880L
- Keywords:
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- 5210 Planetary atmospheres;
- clouds;
- and hazes;
- PLANETARY SCIENCES: ASTROBIOLOGYDE: 6225 Mars;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTSDE: 7899 General or miscellaneous;
- SPACE PLASMA PHYSICSDE: 7999 General or miscellaneous;
- SPACE WEATHER