Search Publications
Stability and instability of Langmuir waves via active subspace decompositions
Mattingly, G.; Longaker, B.; Palmer, N. +2 more
We study the stability and instability of Langmuir waves propagating in a hot, unmagnetized plasma modeled by the Vlasov–Poisson system and encompassing a variety of velocity distributions, including perturbations of Lorentzian, Kappa, and incomplete Maxwellian steady states. The influence of both high-frequency spatial perturbations and physical …
Alfvénic fluctuations in the expanding solar wind: Formation and radial evolution of spherical polarization
Hellinger, P.; Matteini, L.; Horbury, T. S. +7 more
We investigate properties of large-scale solar wind Alfvénic fluctuations and their evolution during radial expansion. We assume a strictly radial background magnetic field B ∥ R, and we use two-dimensional hybrid (fluid electrons, kinetic ions) simulations of balanced Alfvénic turbulence in the plane orthogonal to B; the simulated plasma evolves …
Kinetic numerical scaling of Alfven cyclotron instability in non-thermal solar wind plasmas
Shahzad, Muhammad Ahsan; Aman-ur-Rehman; Bilal, Muhammad +3 more
Linear plasma kinetic theory for a non-thermal, magnetized, homogeneous, and collisionless plasma is incorporated to study Alfvén cyclotron instability (ACI) driven by the ion/proton perpendicular temperature anisotropy (T⊥p/T∥p>1) ( ⊥, ∥ symbols designate directions perpendicular and parallel to ambient magnetic field, respectively), and the w…
Energy transfer of the solar wind turbulence based on Parker solar probe and other spacecraft observations
He, Jiansen; Wang, Xin; Tu, Chuanyi +2 more
The supersonic solar wind, first predicted by Parker and then observed by Mariners, extends to form a heliosphere around the Sun. The energy supply from the energy containing range, the energy cascade though the inertial range, and the eventual energy dissipation are three basic processes of the energy transfer in the solar wind and have been stud…
The electric fields and "lightning jets" of the Sun and solar wind
Driscoll, C. F.
A model of electric energization of the solar wind and corona is developed, including electro-magnetic particle effects precluded by traditional magneto-hydro (MHD) assumptions. Using standard 1D radial solar models for particle density and temperature, the core gravito-electric field is calculated; and the range of possible photospheric photo-ele…
Kinetic study of ion acoustic waves in Venusian ionosphere
Lakhina, G. S.; Kamalam, T.; Singh, S. V. +1 more
Kinetic dispersion of the ion acoustic waves has been explored for an unmagnetized five component plasma system comprising of Venusian protons, Venusian oxygen ions, Venusian electrons, solar wind protons, and kappa electrons. The solar wind protons and electrons are assumed to be streaming along the ambient magnetic field. The plasma parameters f…
Statistics of beam-driven waves in plasmas with ambient fluctuations: Reduced-parameter approach
Robinson, P. A.; Tyshetskiy, Yu.; Cairns, I. H.
A reduced-parameter (RP) model of quasilinear wave-plasma interactions is used to analyze statistical properties of beam-driven waves in plasmas with ambient density fluctuations. The probability distribution of wave energies in such a system is shown to have a relatively narrow peak just above the thermal wave level, and a power-law tail at high …
Parametric instabilities of parallel propagating incoherent Alfvén waves in a finite ion beta plasma
Nariyuki, Y.; Hada, T.; Tsubouchi, K.
Large amplitude, low-frequency Alfvén waves constitute one of the most essential elements of magnetohydrodynamic (MHD) turbulence in the fast solar wind. Due to small collisionless dissipation rates, the waves can propagate long distances and efficiently convey such macroscopic quantities as momentum, energy, and helicity. Since loading of such qu…
Dependence of frequency of nonlinear cold plasma cylindrical oscillations on electron density
Fainberg, J.; Osherovich, Vladimir
For cold plasma, the frequency of small amplitude Langmuir oscillations along one Cartesian coordinate is ωpo=√4πe2no/me , where np=no is the constant proton density which is equal to the average electron density ne¯. This formula for ωpo is the basis for measu…
Electron heat flux constraints in the solar wind
Gary, S. Peter; Daughton, William; Skoug, Ruth M.
Enhanced fluctuations from electromagnetic heat flux instabilities may, through wave-particle scattering, constrain the electron heat flux which flows parallel to the background magnetic field in the solar wind. A corollary of this hypothesis is that instability thresholds should correspond to observable bounds on the heat flux. Here plasma and ma…