Numerical comparison between a gyrofluid and gyrokinetic model investigating collisionless magnetic reconnection

Zacharias, O.; Comisso, Luca; Grasso, D.; Kleiber, R.; Borchardt, M.; Hatzky, R.

doi:10.1063/1.4882679

Cited by 7 publications

(4 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…At small scales ℓ ≪ L the fluid description formally breaks down, but it has been shown that gyrofluid RMHD models capture the essential physics of gyrokinetic reconnection [73]. A good agreement between our collisionless RMHD equations at ρ s = 0 and a drift-kinetic model for magnetic reconnection was already pointed out [49].…”

Section: B Kinetic Effects In the Transition To The Inertial Ideal Te...supporting

confidence: 61%

"Ideal" tearing and the transition to fast reconnection in the weakly collisional MHD and EMHD regimes

Del Sarto,

Pucci,

Tenerani

et al. 2015

Preprint

View full text Add to dashboard Cite

This paper discusses the transition to fast growth of the tearing instability in thin current sheets in the collisionless limit where electron inertia drives the reconnection process. It has been previously suggested that in resistive MHD there is a natural maximum aspect ratio (ratio of sheet length and breadth to thickness) which may be reached for current sheets with a macroscopic length L, the limit being provided by the fact that the tearing mode growth time becomes of the same order as the Alfvén time calculated on the macroscopic scale (Pucci and Velli (2014) [54]). For current sheets with a smaller aspect ratio than critical the normalized growth rate tends to zero with increasing Lundquist number S, while for current sheets with an aspect ratio greater than critical the growth rate diverges with S. Here we carry out a similar analysis but with electron inertia as the term violating magnetic flux conservation: previously found scalings of critical current sheet aspect ratios with the Lundquist number are generalized to include the dependence on the ratio d 2 e /L 2 where de is the electron skin depth, and it is shown that there are limiting scalings which, as in the resistive case, result in reconnecting modes growing on ideal time scales. Finite Larmor Radius effects are then included and the rescaling argument at the basis of "ideal" reconnection is proposed to explain secondary fast reconnection regimes naturally appearing in numerical simulations of current sheet evolution.

show abstract

Section: B Kinetic Effects In the Transition To The Inertial Ideal Te...supporting

confidence: 61%

"Ideal" tearing and the transition to fast reconnection in the weakly collisional MHD and EMHD regimes

Del Sarto,

Pucci,

Tenerani

et al. 2015

Preprint

View full text Add to dashboard Cite

show abstract

“…The fourfield gyrofluid model advances the first two moments of the distribution function for each species, or the ion and electron densities and parallel momenta. Zacharias et al have shown that simulations of magnetic reconnection using this model are in good agreement with gyrokinetic simulations, 31 and Comisso et al have used it to bring to light the acceleration of magnetic reconnection by nonlocal gyrofluid effects. 32 Grasso et al, by contrast, have used it to examine the stabilizing effects of ion diamagnetic drifts on the growth and saturation of tearing modes in inhomogeneous plasma.…”

Section: Introductionmentioning

confidence: 89%

A Hamiltonian Five-Field Gyrofluid Model

Charidakos,

Waelbroeck,

Morrison

2015

Preprint

View full text Add to dashboard Cite

A Lie-Poisson bracket is presented for a five-field gyrofluid model, thereby showing the model to be Hamiltonian. The model includes the effects of magnetic field curvature and describes the evolution of the electron and ion gyro-center densities, the parallel component of the ion and electron velocities, and the ion temperature. The quasineutrality property and Ampere's law determine respectively the electrostatic potential and magnetic flux. The Casimir invariants are presented, and shown to be associated to five Lagrangian invariants advected by distinct velocity fields. A linear, local study of the model is conducted both with and without Landau and diamagnetic resonant damping terms. Stability criteria and dispersion relations for the electrostatic and the electromagnetic cases are derived and compared with their analogs for fluid and kinetic models.

show abstract

“…2011; Zocco & Schekochihin 2011; Zacharias et al. 2014; Numata & Loureiro 2015; Rogers et al. 2007).…”

Section: Introductionunclassified

“…This study is conducted through a comparison of gyrofluid and gyrokinetic simulations. Previously, the gyrokinetic method was successfully employed to examine reconnection (Pueschel et al 2011;Zocco & Schekochihin 2011;Zacharias et al 2014;Numata & Loureiro 2015;Rogers et al 2007). Both approaches are assuming that the plasma is immersed in a strong guide field oriented along the z direction.…”

Section: Introductionmentioning

confidence: 99%

Investigation of the collisionless plasmoid instability based on gyrofluid and gyrokinetic integrated approach

et al. 2023

Self Cite

View full text Add to dashboard Cite

In this work, the development of two-dimensional current sheets with respect to tearing modes, in collisionless plasmas with a strong guide field, is analysed. During their nonlinear evolution, these thin current sheets can become unstable to the formation of plasmoids, which allows the magnetic reconnection process to reach high reconnection rates. We carry out a detailed study of the effect of a finite $\beta _e$ , which also implies finite electron Larmor radius effects, on the collisionless plasmoid instability. This study is conducted through a comparison of gyrofluid and gyrokinetic simulations. The comparison shows in general a good capability of the gyrofluid models in predicting the plasmoid instability observed with gyrokinetic simulations. We show that the effects of $\beta _e$ promotes the plasmoid growth. The effect of the closure applied during the derivation of the gyrofluid model is also studied through the comparison among the variations of the different contributions to the total energy.

show abstract

Numerical comparison between a gyrofluid and gyrokinetic model investigating collisionless magnetic reconnection

Cited by 7 publications

References 40 publications

"Ideal" tearing and the transition to fast reconnection in the weakly collisional MHD and EMHD regimes

"Ideal" tearing and the transition to fast reconnection in the weakly collisional MHD and EMHD regimes

A Hamiltonian Five-Field Gyrofluid Model

Investigation of the collisionless plasmoid instability based on gyrofluid and gyrokinetic integrated approach

Contact Info

Product

Resources

About