Open AccessPronounced enhancements of pickup hydrogen and helium in high‐latitude compressional regions
Author(s) -
Schwadron N. A.,
Zurbuchen T. H.,
Fisk L. A.,
Gloeckler G.
Publication year - 1999
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 - 10.1029/1998ja900054
Subject(s) - mean free path , physics , helium , solar wind , pickup , latitude , turbulence , computational physics , scattering , hydrogen , mechanics , atmospheric sciences , plasma , atomic physics , optics , astronomy , nuclear physics , quantum mechanics , artificial intelligence , computer science , image (mathematics)
Pickup hydrogen and helium distributions are measured in compressive corotating regions at high heliographic latitudes. The enhancements can be explained using a pickup ion transport model which includes compression but requires a long scattering mean free path. The long mean free path is generally observed for pickup ions at high latitudes, but it is not explained by current theories of wave‐particle interaction. The feet that the mean free path is not reduced in the high‐latitude compressed events suggests that the long mean free path is not isolated to highly static solar wind conditions. It also has important implications for wave‐particle interaction theories since the turbulence within the compressed events is expected to be qualitatively different from the turbulence in static noncompressed solar wind.