Explanatory notes:
The electron pitch-angle distribution averages included in this data set are
derived from integrating the electron pitch-angle distributions measured by the
Wind/SWE electron instrument (see Ogilvie et al., "SWE, a comprehensive plasma
instrument for the Wind spacecraft", Space Sci. Rev., 71, 55, 1955). Averages
of phase-space density (f) over key regions of the unit sphere (the set of all
possible electron velocity directions) are computed from 9s measurements which
are usually separated by one or more 3s spin-periods. These quantities are
reliable and citable with caution, meaning that the PI advises that the user
should discuss their interpretations with a member of the SWE science team
before publishing.
The following comments are intended to aid in the use and interpretation of the
averages reported in this data set. We begin this analysis with a measure of f
for each pitch-angle bin, six degrees in width, from 0 degrees (flux nearly
parallel to B) to 180 degrees (flux nearly anti-parallel with B). The f values
for pitch-angles from 0-90 degrees (parallel streaming) are integrated (with
angluar weighting and assumptions of gyrotropy) over this half-sphere, then
averaged by dividing out the 2-pi solid angle of the half-sphere; the result
being referred to as the 'f_para' average. Similarly, the 'f_perp' (flux nearly
perpendicular to B) average is the result of integrating f for pitch-angles from
60-120 degrees (a region also 2-pi in solid angle). Next, the 'f_anti' (flux
nearly anti-parallel to B) average covers the half-sphere of "backward"
streaming electrons; having pitch-angles from 90-180 degrees. Finally, the
'f_omni' (omni-directional) average provides the integral of f over the full
sphere, divided by the full 4-pi solid angle; providing a measure of total
electron flux into the region of observation.
The above analysis is carried out for each of 13 energy channels: E = 19.34,
38.68, 58.03, 77.37, 96.71, 116.1, 193.4, 290.1, 425.5, 580.3, 773.7, 1006., and
1238. eV. For reference, the electron speeds (|V|, in cm/s) corresponding to
these energies are reported in this data set. Hence the data set reported here
contains: f_para, f_perp, f_anti, f_omni (for each of 13 values of E), and the
13 values of |V| (constant, included for reference).