Search Publications
Tripolar guide magnetic fields due to island coalescence in solar wind current sheets: Simulation and theory
Newman, David L.; Eriksson, Stefan; Lapenta, Giovanni
Reconnecting current sheets (CSs) in the solar wind near 1 AU have been previously identified that exhibit a modified Hall magnetic field perturbation of the nominal guide field characterized by a "tripolar" structure with depressions on both sides of a central maximum [Eriksson et al., Astrophys. J. 805, 43 (2015)]. Such CSs were inferred to cont…
Turbulence in space plasmas: Who needs it?
Matthaeus, W. H.
The complex nonlinear dynamical phenomenon described as turbulence, is known to have a great impact on fluids, magnetohydrodynamic systems, and on plasmas. This paper reviews selected topics on turbulence in these systems, emphasizing the multiscale space-time properties of the turbulence cascade as it transfers energy from large scale reservoirs,…
Cold ion energization at separatrices during magnetic reconnection
Divin, A.; Deca, J.; Markidis, S. +5 more
Separatrices of magnetic reconnection host intense perpendicular Hall electric fields. The fields are produced by the decoupling of the ion and electron components and are associated with the in-plane electrostatic potential drop between the inflow and outflow regions. The width of these structures is typically less than the ion inertial length, w…
Interaction of electron acoustic waves in the presence of superthermal electrons in terrestrial magnetosphere
Masood, W.; Jahangir, R.
We have investigated the propagation and interaction of nonlinear electron acoustic waves (EAWs) in a plasma comprising hot (superthermal) and cold electrons and immobile ions. We have derived the Korteweg-de Vries equation for EAWs in the small amplitude limit. Employing the Hirota's Direct method, we have investigated the multisoliton solutions …
Reconnection from a turbulence perspective
Eastwood, J. P.; Matthaeus, W. H.; Stawarz, J. E. +6 more
The spectral properties associated with laminar, anti-parallel reconnection are examined using a 2.5D kinetic particle in cell simulation. Both the reconnection rate and the energy spectrum exhibit three distinct phases: an initiation phase where the reconnection rate grows, a quasi-steady phase, and a declining phase where both the reconnection r…
Overtaking collisions of double layers and solitons: Tripolar structures and dynamical polarity switches
Olivier, C. P.; Verheest, F.
Overtaking collisions between double layers and solitons are investigated through the numerical simulation of the Gardner equation that governs small-amplitude double layers. The results show that the double layer emerges unaffected after the completion of the collision. However, the soliton that emerges from the collision has the opposite polarit…
Resonant instabilities of kinetic Alfvén waves in the Earth's magnetosphere with superthermal electrons
Lakhina, G. S.; Singh, S. V.; Barik, K. C.
A theoretical plasma model for the generation of kinetic Alfvén waves (KAWs), having background Maxwellian ions, κ-electrons, and drifting Maxwellian beam ions, is discussed. The ion beam streams along the ambient magnetic field, whereas velocity shear is perpendicular to it. The role played by nonthermal electrons in the excitation of resonant KA…
Electron trapping in the coma of a weakly outgassing comet
Divin, Andrey; Deca, Jan; Olshevsky, Vyacheslav +2 more
Measurements from the Rosetta mission have shown a multitude of nonthermal electron distributions in the cometary environment, challenging the previously assumed plasma interaction mechanisms near a cometary nucleus. In this paper, we discuss electron trapping near a weakly outgassing comet from a fully kinetic (particle-in-cell) perspective. Usin…
Vibrational and electronic collisional-radiative model in CO2-N2-Ar mixtures for Mars entry problems
Annaloro, Julien; Bultel, Arnaud
To predict the nonequilibrium flows around a hypersonic vehicle entering the Martian atmosphere, the two-temperature collisional-radiative model "CoRaM-MARS" has been developed. The species CO2, CO, C2, CN, N2, NO, O2, C, N, O, Ar, CO+, C2 + , CN+, N…
Generation of kinetic Alfvén waves in dayside magnetopause reconnection: A 3-D global-scale hybrid simulation
Wang, Xueyi; Lin, Yu; Guo, Zhifang +1 more
In this paper, we perform a three-dimensional (3-D) global-scale hybrid simulation to investigate the generation of kinetic Alfvén waves (KAWs) in reconnection at the dayside magnetopause. In the simulation, the magnetopause reconnection takes place due to a self-consistent interaction between the solar wind and Earth's magnetosphere, in which the…