An introductory guide to fluid models with anisotropic temperatures. Part 1. CGL description and collisionless fluid hierarchy

Hunana, P.; Tenerani, Anna; Zank, G. P.; Khomenko, E.; Goldstein, M. L.; Webb, G. M.; Cally, Paul Stuart; Collados, M.; Velli, M.; Adhikari, L.

doi:10.1017/s0022377819000801

Cited by 46 publications

(77 citation statements)

References 98 publications

(259 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Macroscopic equations for a collisionless plasma with pressure anisotropy have been derived in Chew, Goldberger & Low (1956). A detailed review of the anisotropic Chew-Goldberger-Low (CGL) model as well as of other collisionless fluid models is provided in Hunana et al (2019). Pressure anisotropy is usually responsible for various instabilities, such as the firehose and the mirror instabilities.…”

Section: Introductionmentioning

confidence: 99%

On the linear stability of anisotropic pressure equilibria with field-aligned incompressible flow

Evangelias

Throumoulopoulos

2020

J. Plasma Phys.

View full text Add to dashboard Cite

We derive a sufficient condition for the linear stability of plasma equilibria with incompressible flow parallel to the magnetic field, $\boldsymbol{B}$ , constant mass density and anisotropic pressure such that the quantity $\unicode[STIX]{x1D70E}_{d}=\unicode[STIX]{x1D707}_{0}(P_{\Vert }-P_{\bot })/B^{2}$ , where $P_{\Vert }$ ( $P_{\bot }$ ) is the pressure tensor element parallel (perpendicular) to $\boldsymbol{B}$ , remains constant. This condition is applicable to any steady state without geometrical restriction. The condition, generalising the respective condition for magnetohydrodynamic equilibria with isotropic pressure and constant density derived in Throumoulopoulos & Tasso (Phys. Plasmas, vol. 14, 2007, 122104), involves physically interpretable terms related to the magnetic shear, the flow shear and the variation of total pressure perpendicular to the magnetic surfaces. On the basis of this condition we prove that, if a given equilibrium is linearly stable, then the ones resulting from the application of Bogoyavlenskij symmetry transformations are linearly stable too, provided that a parameter involved in those transformations is positive. In addition, we examine the impact of pressure anisotropy, flow and torsion of a helical magnetic axis, for a specific class of analytic equilibria. In this case, we find that the pressure anisotropy and the flow may have either stabilising or destabilising effects. Also, helical configurations with small torsion and large pitch seem to have more favourable stability properties.

show abstract

Section: Introductionmentioning

confidence: 99%

On the linear stability of anisotropic pressure equilibria with field-aligned incompressible flow

Evangelias

Throumoulopoulos

2020

J. Plasma Phys.

View full text Add to dashboard Cite

show abstract

“…However, that equation of state was derived considering only the adiabatic trapping of electrons as the primary source of anisotropy. A further step can be taken by introducing a more general fluid model that includes dynamic electron-pressure anisotropy (Chew et al 1956;Hunana et al 2019b), electron finite-Larmor-radius (FLR) effects, and/or electron Landau damping (e.g., Hammett & Perkins 1990;Sulem & Passot 2015;Hunana et al 2019a).…”

Section: Introductionmentioning

confidence: 99%

Bridging hybrid- and full-kinetic models with Landau-fluid electrons

Finelli

Cerri

Califano

et al. 2021

A&A

View full text Add to dashboard Cite

Context. Magnetic reconnection plays a fundamental role in plasma dynamics under many different conditions, from space and astrophysical environments to laboratory devices. High-resolution in situ measurements from space missions allow naturally occurring reconnection processes to be studied in great detail. Alongside direct measurements, numerical simulations play a key role in the investigation of the fundamental physics underlying magnetic reconnection, also providing a testing ground for current models and theory. The choice of an adequate plasma model to be employed in numerical simulations, while also compromising with computational cost, is crucial for efficiently addressing the problem under study. Aims. We consider a new plasma model that includes a refined electron response within the “hybrid-kinetic framework” (fully kinetic protons and fluid electrons). The extent to which this new model can reproduce a full-kinetic description of 2D reconnection, with particular focus on its robustness during the nonlinear stage, is evaluated. Methods. We perform 2D simulations of magnetic reconnection with moderate guide field by means of three different plasma models: (i) a hybrid-Vlasov-Maxwell model with isotropic, isothermal electrons, (ii) a hybrid-Vlasov-Landau-fluid (HVLF) model where an anisotropic electron fluid is equipped with a Landau-fluid closure, and (iii) a full-kinetic model. Results. When compared to the full-kinetic case, the HVLF model effectively reproduces the main features of magnetic reconnection, as well as several aspects of the associated electron microphysics and its feedback onto proton dynamics. This includes the global evolution of magnetic reconnection and the local physics occurring within the so-called electron-diffusion region, as well as the evolution of species’ pressure anisotropy. In particular, anisotropy-driven instabilities (such as fire-hose, mirror, and cyclotron instabilities) play a relevant role in regulating electrons’ anisotropy during the nonlinear stage of magnetic reconnection. As expected, the HVLF model captures all these features, except for the electron-cyclotron instability.

show abstract

“…A collisional Weibel instability has been investigated by many authors in recent years. [16,[23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] Stress effect has been neglected in the calculation of the growth rate of the collisional Weibel instability in laser-plasma interaction. The unstable Weibel mode, driven by the anisotropy in the distribution function caused by the heat flow, can have significant growth rates occurring at densities above critical.…”

Section: Introductionmentioning

confidence: 99%

Study of Coulomb collisional effects on the propagation of electromagnetic waves in a turbulent plasma

Azadboni

2020

Contributions to Plasma Physics

View full text Add to dashboard Cite

The presence of Weibel instability in laser-irradiated fuel could be detrimental to the process of ablative implosion, which is necessary for achieving thermonuclear fusion reactions. In this paper, the effect of the Coulomb collisional within the turbulent plasma on the Weibel instability growth rate has been investigated for linear and circular polarization. The results indicate that the Weibel instability growth rate at circular polarization near the ignition centre of the fuel fusion (collisional plasma) is about 10 5 times higher than the collisional Weibel instability growth rate at linear polarization. The Weibel instability growth rate is observed near the critical density of the fuel fusion (collisionless plasma) at linear polarization and enhancement near the foot of the heat in front of the fuel fusion. By increasing the steps of the density gradient plasma in the low-density corona, electromagnetic instability occurs at a higher stress flow. Therefore, the deposition condition of electron beam energy in circular polarization of turbulent plasma can be shifted to the fuel core for suitable ignition.

show abstract

An introductory guide to fluid models with anisotropic temperatures. Part 1. CGL description and collisionless fluid hierarchy

Cited by 46 publications

References 98 publications

On the linear stability of anisotropic pressure equilibria with field-aligned incompressible flow

On the linear stability of anisotropic pressure equilibria with field-aligned incompressible flow

Bridging hybrid- and full-kinetic models with Landau-fluid electrons

Study of Coulomb collisional effects on the propagation of electromagnetic waves in a turbulent plasma

Contact Info

Product

Resources

About