An Energetic Electron Flux Dropout Due to Magnetopause Shadowing on 1 June 2013
Abstract
We examine the mechanisms responsible for the dropout of energetic electron flux during 31 May to 1 June 2013 using Van Allen Probe (Radiation Belt Storm Probes (RBSP)) electron flux data and simulations with the Comprehensive Inner Magnetosphere‐Ionosphere (CIMI) model. During the storm main phase, L‐shells at RBSP locations are greater than ~8, which are connected to open drift shells. Consequently, diminished electron fluxes were observed over a wide range of energies. The combination of drift shell splitting, magnetopause shadowing, and drift loss all results in butterfly electron pitch angle distributions (PADs) at the nightside. During storm sudden commencement, RBSP observations display electron butterfly PADs over a wide range of energies. However, it is difficult to determine whether there are butterfly PADs during the storm main phase since the maximum observable equatorial pitch angle from RBSP is not larger than ~40° during this period. To investigate the causes of the dropout, the CIMI model is used as a global 4‐D kinetic inner magnetosphere model. The CIMI model reproduces the dropout with very similar timing and flux levels and PADs along the RBSP trajectory for 593 keV. Furthermore, the CIMI simulation shows butterfly PADs for 593 keV during the storm main phase. Based on comparison of observations and simulations, we suggest that the dropout during this event mainly results from magnetopause shadowing.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 01, 2018
- Source ID
- 10.1002/2017ja024879
Entities
People
- Alex Glocer
- Colin Komar
- Mei-Ching Fok
- N. Buzulukova
- S. B. Kang
- Wen Li
Organizations
- Air Force Office of Scientific Research
- Boston University
- National Aeronautics and Space Administration
- The Catholic University of America
- University of Maryland