Solar Energetic Proton Access and Trapping in the Inner Magnetosphere: Van Allen Probes and DSX Measurements
Abstract
We propose to address three Science Questions regarding impact of geomagnetic activity on Solar Energetic Proton (SEP) access to the magnetosphere and effects of geomagnetic activity on inner zone protons using measurements from the Van Allen Probes Relativistic Electron Proton Telescope (REPT) and the Demonstration and Science Experiments (DSX) energetic proton measurements: 1) How are Solar Energetic Proton cutoffs modified by geomagnetic activity? 2) How does Solar Energetic Proton trapping occur? 3) How does geomagnetic activity modify the outer boundary of inner zone protons? Two SEP events in September 2017 with VAP measurements are ideal for analyzing (1) – (3): a strong SEP event (11 September) with no geomagnetic storm and a strong storm with weaker SEP fluxes. The 7 – 9 September storm event produced SEP trapping shown to contribute trapped flux at the variable outer boundary of inner zone protons. Another pair of events in May 2013 will be studied for the effect of ring current buildup on lower altitude SEP access and trapping. Both time-stepped empirical Tsyganenko-Sitnov and Lyon-Fedder-Mobarry MHD simulations, driven by L1 solar wind input, will be used as field models to calculate cutoff suppression and trapping of SEPs with the rbelt3D particle tracing code developed at Dartmouth.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2021
- Source ID
- FA95502010339
Entities
People
- M. K. Hudson
Organizations
- Air Force Office of Scientific Research
- Board of Trustees of Dartmouth College
- United States Air Force