Search Publications
Review article: Wave analysis methods for space plasma experiment
Narita, Yasuhito
A review of analysis methods is given on quasi-monochromatic waves, turbulent fluctuations, and wave-wave and wave-particle interactions for single-spacecraft data in situ in near-Earth space and interplanetary space, in particular using magnetic field and electric field data. Energy spectra for different components of the fluctuating fields, mini…
Brief Communication: The double layer in the separatrix region during magnetic reconnection
Guo, J.; Yu, B.
With two-dimensional (2-D) particle-in-cell (PIC) simulations we investigate the evolution of the double layer (DL) driven by magnetic reconnection. Our results show that an electron beam can be generated in the separatrix region as magnetic reconnection proceeds. This electron beam could trigger the ion-acoustic instability; as a result, a DL acc…
Wavevector anisotropy of plasma turbulence at ion kinetic scales: solar wind observations and hybrid simulations
Narita, Y.; Motschmann, U.; Comişel, H.
Wavevector anisotropy of ion-scale plasma turbulence is studied at various values of ion beta. Two complementary methods are used. One is multi-point measurements of magnetic field in the near-Earth solar wind as provided by the Cluster spacecraft mission, and the other is hybrid numerical simulation of two-dimensional plasma turbulence. Both meth…
Four-dimensional energy spectrum for space-time structure of plasma turbulence
Narita, Y.
A parametric model of the inertial-range energy spectrum is constructed for plasma turbulence in the four-dimensional wave vector and frequency domain. The model is based on that of the Eulerian wavenumber-frequency spectrum developed for describing fluid turbulence, and includes wave vector anisotropies in the three-dimensional wave vector domain…
Effect of interchange instability on magnetic reconnection
Goldstein, M. L.; Lyatsky, W.
We present here the results of a study of interacting magnetic fields that involves a force normal to the reconnection layer. In the presence of such force, the reconnection layer becomes unstable to interchange disturbances. The interchange instability results in formation of tongues of heated plasma that leaves the reconnection layer through its…
Turbulence in a global magnetohydrodynamic simulation of the Earth's magnetosphere during northward and southward interplanetary magnetic field
Richard, R. L.; El-Alaoui, M.; Walker, R. J. +2 more
We report the results of MHD simulations of Earth's magnetosphere for idealized steady solar wind plasma and interplanetary magnetic field (IMF) conditions. The simulations feature purely northward and southward magnetic fields and were designed to study turbulence in the magnetotail plasma sheet. We found that the power spectral densities (PSDs) …
Magnetic reconnection as an element of turbulence
Carbone, V.; Matthaeus, W. H.; Wan, M. +6 more
In this work, recent advances on the study of reconnection in turbulence are reviewed. Using direct numerical simulations of decaying incompressible two-dimensional magnetohydrodynamics (MHD), it was found that in fully developed turbulence complex processes of reconnection locally occur (Servidio et al., 2009, 2010a). In this complex scenario, re…
Electron acoustic solitons in the presence of an electron beam and superthermal electrons
Lakhina, G. S.; Singh, S. V.; Bharuthram, R. +1 more
Arbitrary amplitude electron acoustic solitons are studied in an unmagnetized plasma having cold electrons and ions, superthermal hot electrons and an electron beam. Using the Sagdeev pseudo potential method, theoretical analysis is carried out by assuming superthermal hot electrons having kappa distribution. The results show that inclusion of an …
Turbulent spectra and spectral kinks in the transition range from MHD to kinetic Alfvén turbulence
de Keyser, J.; Voitenko, Y.
A weakly dispersive range (WDR) of kinetic Alfvén turbulence is identified and investigated for the first time in the context of the MHD/kinetic turbulence transition. We find perpendicular wavenumber spectra ∝ k\bot-3 and ∝ k\bot-4 formed in WDR by strong and weak turbulence of kinetic Alfvén waves (KAW…
The evolution of electron current sheet and formation of secondary islands in guide field reconnection
Yang, Z.; Wang, S.; Huang, C. +3 more
Two-dimensional (2-D) particle-in-cell (PIC) simulations are performed to investigate the evolution of the electron current sheet (ECS) in guide field reconnection. The ECS is formed by electrons accelerated by the inductive electric field in the vicinity of the X line, which is then extended along the x direction due to the imbalance between the …