Premium
Temporal and Spatial Correspondence of Pc1/EMIC Waves and Relativistic Electron Precipitations Observed With Ground‐Based Multi‐Instruments on 27 March 2017
Author(s) -
Hirai A.,
Tsuchiya F.,
Obara T.,
Kasaba Y.,
Katoh Y.,
Misawa H.,
Shiokawa K.,
Miyoshi Y.,
Kurita S.,
Matsuda S.,
Connors M.,
Nagatsuma T.,
Sakaguchi K.,
Kasahara Y.,
Kumamoto A.,
Matsuoka A.,
Shoji M.,
Shinohara I.,
Albert J. M.
Publication year - 2018
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2018gl080126
Subject(s) - emic and etic , electron precipitation , physics , van allen radiation belt , geophysics , van allen probes , ionosphere , astrophysics , computational physics , electron , radio wave , atmospheric sciences , geology , magnetosphere , magnetic field , nuclear physics , quantum mechanics , sociology , anthropology
Electromagnetic ion cyclotron (EMIC) waves potentially cause precipitation loss of relativistic electrons from the outer radiation belt to the atmosphere through pitch angle scattering. However, the direct evidence of each EMIC wave element and burst of precipitation has not yet been reported. Here we show the temporal and spatial correspondence of the EMIC waves with relativistic electron precipitation (REP) during the geomagnetic storm of 27 March 2017. EMIC waves were observed at several stations in North America. REP was detected as a decrease of subionospheric radio amplitudes observed at Athabasca, Canada. When isolated proton aurora, observed at Athabasca, appeared on the radio propagation path, we found a good correspondence between the temporal variations of REP and EMIC waves, and REP preceded EMIC waves by 24 s. This time lag is consistent with the travel time difference between relativistic electrons and EMIC waves from the magnetospheric equatorial plane to the ionosphere.