Year: 2024
Type: article
Abstract: Recent studies have suggested that the interplanetary magnetic field (IMF) component modulates particle precipitation during solstices, or periods of high dipole tilt . So far this explicit IMF ‐effect has only been shown in statistical studies. Here we analyzed a sequence of high‐speed stream (HSS) driven events of auroral ( keV) and medium energy ( keV and keV) particle precipitation. We show that when HSSs are comparable in terms of IMF and solar wind parameters, they can lead to systematically stronger particle precipitation in individual events when the signs of and are opposite. We also perform a superposed epoch analysis of 485 HSSs giving further evidence that the ‐effect is especially significant during HSSs. This is likely due to the persistent IMF polarity during HSSs. We show evidence that the dependence in particle precipitation is caused by a similar dependence in substorm occurrence.
Source: Geophysical Research Letters
DOI: 10.1029/2024gl110877
Authors: J. Laitinen, L. Holappa, H. Vanhamäki
Institution: University of Oulu
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,900
OpenAlex ID: W4402129049