Characteristics of Relativistic Microburst Intensity From SAMPEX Observations Journal Article uri icon



  • AbstractRelativistic electron microbursts are an important electron loss process from the radiation belts into the atmosphere. These precipitation events have been shown to significantly impact the radiation belt fluxes and atmospheric chemistry. In this study we address a lack of knowledge about the relativistic microburst intensity using measurements of 21,746 microbursts from the Solar Anomalous Magnetospheric Particle Explorer (SAMPEX). We find that the relativistic microburst intensity increases as we move inward in L, with a higher proportion of low‐intensity microbursts (<2,250 [MeV cm2 sr s]−1) in the 03–11 magnetic local time region. The mean microburst intensity increases by a factor of 1.7 as the geomagnetic activity level increases and the proportion of high‐intensity relativistic microbursts (>2,250 [MeV cm2 sr s]−1) in the 03–11 magnetic local time region increases as geomagnetic activity increases, consistent with changes in the whistler mode chorus wave activity. Comparisons between relativistic microburst properties and trapped fluxes suggest that the microburst intensities are not limited by the trapped flux present alongside the scattering processes. However, microburst activity appears to correspond to the changing trapped flux; more microbursts occur when the trapped fluxes are enhancing, suggesting that microbursts are linked to processes causing the increased trapped fluxes. Finally, modeling of the impact of a published microburst spectra on a flux tube shows that microbursts are capable of depleting <500‐keV electrons within 1 hr and depleting higher‐energy electrons in 1–23 hr.

publication date

  • July 1, 2019

has restriction

  • bronze

Date in CU Experts

  • October 9, 2020 12:33 PM

Full Author List

  • Douma E; Rodger CJ; Blum LW; O'Brien TP; Clilverd MA; Blake JB

author count

  • 6

Other Profiles

International Standard Serial Number (ISSN)

  • 2169-9380

Electronic International Standard Serial Number (EISSN)

  • 2169-9402

Additional Document Info

start page

  • 5627

end page

  • 5640


  • 124


  • 7