Open AccessRole of low‐frequency modes in organizing the inner heliosphere
Author(s) -
Heinen Oliver,
Lanzerotti Louis J.,
Heber B.,
Kunow H.,
Thomson David J.
Publication year - 2003
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 - 10.1029/2001ja000058
Subject(s) - heliosphere , physics , cosmic ray , proton , spacecraft , astrophysics , harmonics , spherical harmonics , harmonic , computational physics , cosmic cancer database , astronomy , solar wind , nuclear physics , plasma , quantum mechanics , voltage
Cosmic ray proton data (125 to >2000 MeV) measured in the inner three‐dimensional (3‐D) heliosphere over the years from 1993 into 2000 by the KET instrument on the Ulysses spacecraft are examined. The data are parameterized and characterized by fitting products of spherical harmonic and sinusoidal frequency functions to three individual proton energy data sets. It is found that the time dependence of the cosmic ray data sets can be rather well characterized by relatively few variables consisting of low‐order spherical harmonic modes and a few frequencies of the order of a solar cycle. The results can be useful for analytical and computational studies of cosmic rays in the inner 3‐D heliosphere.