On the Existence of Fast Modes in Compressible Magnetohydrodynamic Turbulence

Autor:	Gan, Zhaoming, Li, Hui, Fu, Xiangrong, Du, Senbei
Rok vydání:	2022
Předmět:	Physics - Space Physics Astrophysics - Solar and Stellar Astrophysics Physics - Fluid Dynamics Physics - Plasma Physics
Druh dokumentu:	Working Paper
DOI:	10.3847/1538-4357/ac4d9d
Popis:	We study the existence and property of Fast magnetosonic modes in 3D compressible MHD turbulence by carrying out a number of simulations with compressible and incompressible driving conditions. We use two approaches to determine the presence of Fast modes: mode decomposition based on spatial variations only and spatio-temporal 4D-FFT analysis of all fluctuations. The latter method enables us to quantify fluctuations that satisfy the dispersion relation of Fast modes with finite frequency. Overall, we find that the fraction of Fast modes identified via spatio-temporal 4D FFT approach in total fluctuation power is either tiny with nearly incompressible driving or ~2% with highly compressible driving. We discuss the implications of our results for understanding the compressible fluctuations in space and astrophysics plasmas. Comment: 8 pages, 5 figures; accepted by the Astrophysical Journal for publication
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2201.07965 Zobrazit plný text záznamu View this record from Arxiv