Electron Energy Partition across Interplanetary Shocks. II. Statistics
Abstract
A statistical analysis of 15,210 electron velocity distribution function (VDF) fits, observed within ±2 hr of 52 interplanetary (IP) shocks by the Wind spacecraft near 1 au, is presented. This is the second in a threepart series on electron VDFs near IP shocks. The electron velocity moment statistics for the dense, lowenergy core, tenuous, hot halo, and fieldaligned beam/strahl are a statistically significant list of values illustrated with both histograms and tabular lists for reference and baselines in future work. Given the large statistics in this investigation, the beam/strahl fit results in the upstream are now the most comprehensive attempt to parameterize the beam/strahl electron velocity moments in the ambient solar wind. The median density, temperature, beta, and temperature anisotropy values for the core(halo)[beam/strahl] components, with subscripts ec(eh)[eb], of all fit results, respectively, are {n}_{ec}(h)[b]}∼ 11.3(0.36)[0.17] {cm}}^{3}, {T}_{ec}(h)[b],{tot}}∼ 14.6(48.4)[40.2] {eV}, {β }_{ec}(h)[b],{tot}}∼ 0.93(0.11)[0.05], and {{ \mathcal A }}_{ec}(h)[b]} ∼ 0.98(1.03)[0.93]. This work will also serve as a 1 au baseline and reference for missions like Parker Solar Probe and Solar Orbiter.
 Publication:

The Astrophysical Journal Supplement Series
 Pub Date:
 December 2019
 DOI:
 10.3847/15384365/ab5445
 arXiv:
 arXiv:1909.09050
 Bibcode:
 2019ApJS..245...24W
 Keywords:

 Solar wind;
 Interplanetary shocks;
 Solar coronal mass ejections;
 Solar coronal mass ejection shocks;
 Space plasmas;
 Plasma astrophysics;
 Plasma physics;
 Interplanetary particle acceleration;
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 Astrophysics  Solar and Stellar Astrophysics;
 Physics  Plasma Physics
 EPrint:
 40 pages, 11 figures, 18 tables, to be submitted to Astrophys. J. Suppl