Premium
On the perpendicular scale of electron phase‐space holes
Author(s) -
Franz J. R.,
Kintner P. M.,
Seyler C. E.,
Pickett J. S.,
Scudder J. D.
Publication year - 2000
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 - 10.1029/1999gl010733
Subject(s) - physics , perpendicular , electron , scaling , phase space , phase (matter) , computational physics , electric field , space (punctuation) , scale (ratio) , polar , atomic physics , condensed matter physics , geometry , quantum mechanics , linguistics , philosophy , mathematics
The perpendicular scale of electron phase‐space holes is investigated using electric field data from the Polar Plasma Wave Instrument. We show that the electron phase‐space holes are roughly spherical for Ω e /ω p > 1, and become more oblate (with the perpendicular scale larger than the parallel scale) with decreasing Ω e /ω p . A scaling argument based upon electron gyrokinetic theory is proposed as a possible explanation for the observed scaling. The data indicate that the ratio of the parallel dimension ( L ∥ ) to the perpendicular dimension ( L ⟂ ) is such that L ∥ / L ⟂ ≃ (1 + ρ e ²/λ D ²) −1/2 . Our results provide a connection between the Geotail measurements in the deep magnetotail, where Ω e /ω p ≪ 1, and the FAST measurements in the low altitude auroral zone, where Ω e /ω p ≫ 1.