edu.ucar.opensky::articles:19809 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T02:32:28.786998 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7930w4h Effects of solar wind ultralow-frequency fluctuations on plasma sheet electron temperature: Regression analysis with support vector machine 2017-04-01T00:00:00Z publication https://n2t.org/ark:/85065/d7930w4h https://doi.org/10.1002/2016JA023746 Wang, C. author Kim, H. author Yue, Chao author Weygand, J. M. author Hsu, T. author Chu, X. author UCAR/NCAR - Library publisher To investigate whether ultralow-frequency (ULF) fluctuations from 0.5 to 8.3 mHz in the solar wind and interplanetary magnetic field (IMF) can affect the plasma sheet electron temperature (T-e) near geosynchronous distances, we use a support vector regression machine technique to decouple the effects from different solar wind parameters and their ULF fluctuation power. T-e in this region varies from similar to 0.1 to 10 keV with a median of 1.3 keV. We find that when the solar wind ULF power is weak, T-e increases with increasing southward IMF B-z and solar wind speed, while it varies weakly with solar wind density. As the ULF power becomes stronger during weak IMF B-z (similar to 0) or northward IMF, T-e becomes significantly enhanced, by a factor of up to 10. We also find that mesoscale disturbances in a time scale of a few to tens of minutes as indicated by AE during substorm expansion and recovery phases are more enhanced when the ULF power is stronger. The effect of ULF powers may be explained by stronger inward radial diffusion resulting from stronger mesoscale disturbances under higher ULF powers, which can bring high-energy plasma sheet electrons further toward geosynchronous distance. This effect of ULF powers is particularly important during weak southward IMF or northward IMF when convection electric drift is weak. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright 2017 American Geophysical Union. None eng geoscientificInformation