Hydromagnetic waves in a plasma with finite larmor radius.
Finite ion Larmor radius effect on MHD wave propagation in plasma
MAGNETOHYDRODYNAMIC WAVE↗
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Results for “Finite Larmor radius”
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The effect of finite Larmor radius on the perturbation flow mixing of a collisionless plasma
Finite Larmor radius effects on collisionless plasma perturbation flow mixing in velocity distribution functions
Morioka, S.↗
Finite-larmor-radius Analysis of Laminar Collisionless Shocks
Laminar collisionless fast and slow shock wave theory by finite-Larmor-radius hydromagnetic fluid equations
Coroniti, F. V.↗
The effects of finite Larmor radius on the perturbation flow mixing of a collisionless plasma
Collisionless plasma theory modification to include effects of finite Larmor radius of ion and electron on perturbation flow mixing
Morioka, S.↗
Kinetic-Scale Magnetic Turbulence and Finite Larmor Radius Effects at Mercury
We use a nonstationary generalization of the higher-order structure function technique to investigate statistical properties of the magnetic field fluctuations recorded by MESSENGER spacecraft during its first flyby (01/14/2008) through the near-Mercury space environment, with the emphasis on key boundary regions participating in the solar wind - magnetosphere interaction. Our analysis shows, for the first time, that kinetic-scale fluctuations play a significant role in the Mercury's magnetosphere up to the largest resolvable timescale (approx.20 s) imposed by the signal nonstationariry, suggesting that turbulence at this plane I is largely controlled by finite Larmor radius effects. In particular, we report the presence of a highly turbulent and extended foreshock system filled with packets of ULF oscillations, broad-band intermittent fluctuations in the magnetosheath, ion-kinetic turbulence in the central plasma sheet of Mercury's magnetotail, and kinetic-scale fluctuations in the inner current sheet encountered at the outbound (dawn-side) magnetopause. Overall, our measurements indicate that the Hermean magnetosphere, as well as the surrounding region, are strongly affected by non-MHD effects introduced by finite sizes of cyclotron orbits of the constituting ion species. Physical mechanisms of these effects and their potentially critical impact on the structure and dynamics of Mercury's magnetic field remain to be understood.
Uritsky, V. M.↗
Finite Larmor radius effect on ion pickup at Venus
The interaction of the solar wind with Venus is influenced by the pickup of newly born exospheric oxygen ions by the convecting magnetosheath plasma. The flow and field configuration of the magnetosheath plasma, together with the large gyroradius of the pickup ions, cause mass loading to occur preferentially on one side of the magnetosheath. The observed hemispherical asymmetry in the magnetic field in the near-planet magnetosheath, attributed to this pickup process, is confirmed by direct observation of the picked-up planetary particles. Test particle calculations show that a current system created by ion pickup has the appropriate location and magnitude to account for the magnetic field asymmetry. The results indicate that a fluid treatment of the Venus mass-loading problem is not entirely appropriate; a hybrid or kinetic model is necessary to incorporate the finite Larmor radius of the pickup particles which produces the observed asymmetry.
Phillips, J. L.↗
Hydromagnetic stability
Stability of magnetized plasmas - gravitational instability, effects of finite Larmor radius, frequency, and resistivity
MAGNETOHYDRODYNAMIC STABILITY↗
Finite beta effects in a weakly unstable plasma
Finite beta effects on interchange mode in weakly unstable plasma calculated in finite Larmor radius limit - differential equation to obtain stability properties of arbitrary systems
PLASMA INSTABILITY↗
Finite beta effects in a weakly unstable plasma.
Finite plasma pressure effect on interchange mode in finite Larmor radius weakly unstable regime
PLASMA INSTABILITY↗
Alfven wave damping from finite gyroradius coupling to the ion acoustic mode
Alfven shear waves collisionless damping from finite Larmor radius coupling to ion acoustic mode, observing longitudinal electric field existence
Stefant, R. J.↗
Low-frequency drift oscillations in the magnetosphere
Finite Larmor radius interchange and LF drift oscillations due to magnetospheric temperature and density gradient stresses in trapped plasma
Coroniti, F. V.↗
Strongly magnetized classical plasma models
The class of plasma processes for which the so-called Vlasov approximation is inadequate is investigated. Results from the equilibrium statistical mechanics of two-dimensional plasmas are derived. These results are independent of the presence of an external dc magnetic field. The nonequilibrium statistical mechanics of the electrostatic guiding-center plasma, a two-dimensional plasma model, is discussed. This model is then generalized to three dimensions. The guiding-center model is relaxed to include finite Larmor radius effects for a two-dimensional plasma.
Montgomery, D. C.↗
The electromagnetic interchange mode in a partially ionized collisional plasma
A collisional electromagnetic dispersion relation is derived from two-fluid theory for the interchange mode coupled to the Alfven, acoustic, drift and entropy modes in a partially ionized plasma. The fundamental electromagnetic nature of the interchange model is noted; coupling to the intermediate Alfven mode is strongly stabilizing for finite k sub z. Both ion viscous and ion-neutral stabilization are included, and it was found that collisions destroy the ion finite Larmor radius cutoff at short perpendicular wavelengths.
Hudson, M. K.↗
The electromagnetic interchange mode in a partly-ionized collisional plasma
A collisional electromagnetic dispersion relation is derived from two-fluid theory for the interchange mode coupled to the Alfven, acoustic, drift, and entropy modes in a partially ionized plasma. The fundamental electromagnetic nature of the interchange mode is noted: coupling to the intermediate Alfven mode is strongly stabilizing for finite perturbations of the magnetic field. Both ion-viscous and ion-neutral stabilization are included; and it is found that collisions destroy the FLR (finite Larmor radius) cutoff at short perpendicular wavelengths.
Hudson, M. K.↗
The onset and development of Kelvin-Helmholtz instability at the Venus ionopause
The paper investigates the Kelvin-Helmholtz instability at the Venus ionopause resulting from the flow of the (shocked) solar wind tangential to the ionopause for the case where the interplanetary field is oriented normal to the direction of flow. It is found that gravity stabilizes the long wavelength perturbations, and the finite thickness of the boundary layer stabilizes short wavelength modes. The magnetic 'gyroviscosity' due to finite Larmor radius effects either destabilizes the boundary or stabilizes it according to whether the solar wind electric field points away from or toward the ionosphere. For solar wind and ionosphere plasma parameters consistent with Pioneer Venus observations, it is found that the instabilities with the greatest growth rates (shortest growth times) have wavelengths of 50-150 km and growth times of 0.5 to several seconds. In addition, it is found how distortion of the ionopause by Kelvin-Helmholtz instability might lead to the formation of magnetic 'flux ropes' inside the ionosphere as well as ionospheric 'bubbles' embedded in the solar wind.
Wolff, R. S.↗
Interactions with planetary ionospheres and atmospheres: A review
The interaction of the solar wind with umnagnetized objects possessing an ionosphere is reviewed. Venus, Mars, Titan, comets (including the artificial comet created by AMPTE) and the unusual interplanetary events interpreted as cometesimals are considered. The role of the interplanetary magnetic field and of mass loading in producing the observed interactions is highlighted. Interpretation to date is based largely on an MHD (fluid) treatment, but results from the first AMPTE barium release and from recordings made at Venus suggest that finite Larmor radius effects introduce asymmetries in the solar wind interaction.
Saunders, Mark A.↗
Interactions with planetary ionospheres and atmospheres - A review
The interaction of the solar wind with unmagnetized objects possessing an ionosphere is reviewed, with emphasis on recent developments. Venus, Mars, Titan, comets (including the artificial comet created by AMPTE) and the unusual interplanetary events interpreted as cometesimals are considered. The role of the interplanetary magnetic field and of mass loading in producing the observed interactions are highlighted. Interpretation to date is based largely on an MHD (fluid) treatment, but recent results from the first AMPTE barium release and from recordings made at Venus suggest that finite Larmor radius effects introduce asymmetries in the solar wind interaction.
Saunders, Mark A.↗
An unambiguous determination of the propagation of a compressional Pc 5 wave
A compressional Pc5 event observed by the ISEE-1 magnetometer and Medium Energetic Particle Experiment instrument on August 21 and 22, 1978, is examined. The propagation properties of the compressional waves were determined using a technique which utilizes the finite Larmor radius effects in the signature of the multichannel energetic ion detector. It is shown that this technique determines unambiguously the propagation characteristics of the wave in both the azimuthal and the radial directions in the plane perpendicular to the background magnetic field; the results remained valid even though heavy energetic ions with Larmor radii larger than proton Larmor radii were present in the plasma.
Lin, N.↗