Open AccessThe effect of a distorted interplanetary magnetic field configuration on the December 7–8, 1982, ground level enhancement
Author(s) -
Cramp J. L.,
Duldig M. L.,
Humble J. E.
Publication year - 1997
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/96ja03698
Subject(s) - physics , interplanetary magnetic field , interplanetary spaceflight , computational physics , scattering , cosmic ray , pitch angle , magnetic field , astrophysics , geophysics , solar wind , optics , quantum mechanics
The cosmic ray ground level enhancement (GLE) of December 7–8, 1982, occurred when the interplanetary magnetic field (IMF) direction measured near Earth indicated significant distortion from the nominal form. We have modeled the ground level response to this event to derive rigidity spectra and pitch angle distributions centered on apparent arrival directions. A deficit region associated with a near‐Earth magnetic cloud‐like structure has been modeled during the initial phase of the GLE. Using this modified model, we find agreement between the derived particle arrival directions and the measured IMF directions. We find a significant contribution from pitch angles greater than 90° throughout the event. This is probably due to scattering in the turbulent region behind the cloud‐like structure.