Explanatory notes:
The electron strahl beam descriptions included in this data set are derived
from analyzing 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). These distributions
naturally organize into intervals of phase-space density (f) streaming either
parallel and anti-parallel (to B). Descriptions of f over these intervals 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 beam descriptions 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 ('f_para': parallel streaming
"beam") are described by their peak f value (f_para_INT: beam intensity),
angular width (f_para_WID: beam width, at half-maximum, in degrees), and
angular position of peak (f_para_ANG: pitch-angle of beam, in degrees). The f
values for pitch-angles from 90-180 degrees ('f_anti': anti-parallel streaming
beam) are similarly described by f_anti_INT, f_anti_WID, and f_anti_ANG.
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_INT, f_para_WID, f_para_ANG, f_anti_INT, f_anti_WID,
f_anti_ANG, (for each of 13 values of E), and the 13 values of |V| (constant,
included for reference).