Solar Energetic Proton Access to the Inner Magnetosphere During the September 7–8, 2017 Event

Abstract

The access of solar energetic protons into the inner magnetosphere on September 7–8, 2017 is investigated by following reversed proton trajectories to compute the proton cutoff energy using the Dartmouth geomagnetic cutoff code (Kress et al., 2010, https://doi.org/10.1029/2009sw000488). The cutoff energies for protons coming from the west and east direction, the minimum and maximum cutoff energy respectively, are calculated every 5 min along the orbit of Van Allen Probes using TS07 and the Lyon‐Fedder‐Mobarry (LFM) MHD magnetic field model. The result shows that the cutoff energy increases significantly as the radial distance decreases, and that the cutoff energy decreases with the building up of the ring current during magnetic storms. Solar wind dynamic pressure also affects cutoff suppression (Kress et al., 2004, https://doi.org/10.1029/2003gl018599). The LFM‐RCM model shows stronger suppression of cutoff energy than TS07 during strong solar wind driving conditions. The simulation result is compared with proton flux measurements, showing consistent variation of the cutoff location during the September 7–8, 2017 geomagnetic storm.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 01, 2021
Source ID
10.1029/2021ja029107

Entities

People

  • Brian Kress
  • M. Engel
  • M. K. Hudson
  • Maulik Patel
  • Murong Qin
  • R. S. Selesnick
  • Zhao Li

Organizations

  • Air Force Office of Scientific Research
  • Air Force Research Laboratory
  • Boston University
  • Dartmouth College
  • Los Alamos National Laboratory
  • National Center for Atmospheric Research
  • National Oceanic and Atmospheric Administration
  • University of Colorado Boulder

Tags

Fields of Study

  • Physics

Readers

  • Radar Systems Engineering.
  • Space/Atmospheric Physics.

Technology Areas

  • Space