This content will become publicly available on June 1, 2023
 Award ID(s):
 1655280
 Publication Date:
 NSFPAR ID:
 10355940
 Journal Name:
 The Astrophysical Journal Supplement Series
 Volume:
 260
 Issue:
 2
 Page Range or eLocationID:
 26
 ISSN:
 00670049
 Sponsoring Org:
 National Science Foundation
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We present a detailed guide to advanced collisionless fluid models that incorporate kinetic effects into the fluid framework, and that are much closer to the collisionless kinetic description than traditional magnetohydrodynamics. Such fluid models are directly applicable to modelling the turbulent evolution of a vast array of astrophysical plasmas, such as the solar corona and the solar wind, the interstellar medium, as well as accretion disks and galaxy clusters. The text can be viewed as a detailed guide to Landau fluid models and it is divided into two parts. Part 1 is dedicated to fluid models that are obtained by closing the fluid hierarchy with simple (nonLandau fluid) closures. Part 2 is dedicated to Landau fluid closures. Here in Part 1, we discuss the fluid model of Chew–Goldberger–Low (CGL) in great detail, together with fluid models that contain dispersive effects introduced by the Hall term and by the finite Larmor radius corrections to the pressure tensor. We consider dispersive effects introduced by the nongyrotropic heat flux vectors. We investigate the parallel and oblique firehose instability, and show that the nongyrotropic heat flux strongly influences the maximum growth rate of these instabilities. Furthermore, we discuss fluid models that contain evolution equationsmore »

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