Statistical mapping of ULF Pc3 velocity fluctuations in the Earth's dayside magnetosheath as a function of solar wind conditions

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • Embry-Riddle Aeronautical University

Abstract

In this paper, we present the results of a statistical study of Pc3 velocity fluctuations in the Earth's dayside magnetosheath. There exists a notable dawn-dusk asymmetry, such that velocity fluctuations generally exhibit enhanced spectral power in the magnetosheath downstream of the quasi-parallel shock. The fluctuations in the central magnetosheath and close to bow shock tend to dampen with increasing tail-ward distance while the opposite trend is observed close to the magnetopause. This strongly suggests that velocity shear driven processes such as the Kelvin-Helmholtz instability drive Pc3 flow variations close to the magnetopause as the velocity shear increases with increasing tail-ward distance. We also show strong evidence that Pc3 velocity fluctuations are significantly enhanced during intervals of faster solar wind speeds. We see negligible differences between data collected during northward and southward IMF orientations, but in general, a dawn-favoured asymmetry persists.

Details

Original languageEnglish
Pages (from-to)196-207
Number of pages12
JournalAdvances in Space Research
Volume58
Issue number2
Publication statusPublished - 15 Jul 2016
MoE publication typeA1 Journal article-refereed

    Research areas

  • Kelvin-Helmholtz instability, Magnetosheath, Magnetosphere, Pc3 waves, Velocity turbulence

ID: 6884193