Skip to Main content Skip to Navigation
Journal articles

Shock Drift Acceleration of Ions in an Interplanetary Shock Observed by MMS

Abstract : An interplanetary (IP) shock wave was recorded crossing the Magnetospheric Multiscale constellation on 2018 January 8. Plasma measurements upstream of the shock indicate efficient proton acceleration in the IP shock ramp: 2–7 keV protons are observed upstream for about three minutes (∼8000 km) ahead of the IP shock ramp, outrunning the upstream waves. The differential energy flux of 2–7 keV protons decays slowly with distance from the ramp toward the upstream region (dropping by about half within 8 Earth radii from the ramp) and is lessened by a factor of about four in the downstream compared to the ramp (within a distance comparable to the gyroradius of ∼keV protons). Comparison with test-particle simulations has confirmed that the mechanism accelerating the solar wind protons and injecting them upstream is classical Shock Drift Acceleration (SDA). This example of observed proton acceleration by a low-Mach, quasi-perpendicular shock may be applicable to astrophysical contexts, such as supernova remnants or the acceleration of cosmic rays.
Document type :
Journal articles
Complete list of metadata
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Tuesday, December 7, 2021 - 1:28:57 PM
Last modification on : Wednesday, May 11, 2022 - 4:39:02 AM

Links full text




E. Hanson, O. Agapitov, I. Vasko, F. Mozer, V. Krasnoselskikh, et al.. Shock Drift Acceleration of Ions in an Interplanetary Shock Observed by MMS. The Astrophysical journal letters, Bristol : IOP Publishing, 2020, 891 (1), pp.L26. ⟨10.3847/2041-8213/ab7761⟩. ⟨insu-03468841⟩



Record views