Authors: Dibyendu Sur (NASA GSFC / CUA)

This work examines a solar energetic particle (SEP) event observed by MAVEN at Mars using data from the SEP instrument together with magnetic field measurements from MAG and solar wind measurements from SWIA instruments and WSA-ENLIL model simulations. For example, during September 11-17, 2017, the time-energy spectrogram shows energy flux enhancements beginning around September 13, with higher fluxes spanning about 30 MeV up to several GeV and lasting for a few days. Energy spectra over 30-200 MeV at selected times (start, maximum flux interval, and recovery time) are constructed by averaging over SEP ion channels and fitting power‑law equations. These results indicate a relatively hard spectrum early in the event, a softer spectrum near the peak, and a return toward harder spectrum later in the decay phase. Similar features were also observed in May 2024 event. Magnetic field measurements and spacecraft radial distances are used to observe SEP results, separating intervals when MAVEN was in the solar wind, magnetosheath, or near planetary crustal fields. SWIA instrument observations of solar wind density and velocity characterize the influence of the upstream plasma conditions on the SEP behavior. Together, these analyses demonstrate how combined SEP, MAG, and SWIA data from MAVEN can be used to characterize the timing, spectral variations, and environmental dependence of SEP events at Mars during the specified period. WSA-ENLIL heliospheric simulation demonstrates the upstream solar wind conditions throughout the SEP enhancement.