You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Density Fluctuations in the Solar Wind Driven by Alfvén Wave Parametric Decay
Contributor:
Bowen, Trevor A.;
Badman, Samuel;
Hellinger, Petr;
Bale, Stuart D.
Published:
American Astronomical Society, 2018
Published in:
The Astrophysical Journal Letters, 854 (2018) 2, Seite L33
Language:
Not determined
DOI:
10.3847/2041-8213/aaabbe
ISSN:
2041-8205;
2041-8213
Origination:
Footnote:
Description:
Abstract Measurements and simulations of inertial compressive turbulence in the solar wind are characterized by anti-correlated magnetic fluctuations parallel to the mean field and density structures. This signature has been interpreted as observational evidence for non-propagating pressure balanced structures, kinetic ion-acoustic waves, as well as the MHD slow-mode. Given the high damping rates of parallel propagating compressive fluctuations, their ubiquity in satellite observations is surprising and suggestive of a local driving process. One possible candidate for the generation of compressive fluctuations in the solar wind is the Alfvén wave parametric instability. Here, we test the parametric decay process as a source of compressive waves in the solar wind by comparing the collisionless damping rates of compressive fluctuations with growth rates of the parametric decay instability daughter waves. Our results suggest that generation of compressive waves through parametric decay is overdamped at 1 au, but that the presence of slow-mode-like density fluctuations is correlated with the parametric decay of Alfvén waves.