相关论文: Kappa-Maxwellian electrons and Bi-Maxwellian proto…
The solar corona has been revealed in the past decade to be a highly dynamic nonequilibrium plasma environment. Both the loop-filled coronal base and the extended acceleration region of the solar wind appear to be strongly turbulent, but…
Protons and alpha particles in the fast solar wind are only weakly collisional and exhibit a number of non-equilibrium features, including relative drifts between particle species. Two non-collisional mechanisms have been proposed for…
The nature of solar wind turbulence in the dissipation range at scales much smaller than the large MHD scales remains under debate. Here a two-dimensional model based on the hybrid code abbreviated as A.I.K.E.F. is presented, which treats…
Alfv\'en waves are widely believed to play an important role in the transport of energy from the solar photosphere to the corona through the partially ionized chromosphere. In previous work, the properties of torsional Alfv\'en waves were…
We develop a model for stochastic acceleration of electrons in solar flares. As in several previous models, the electrons are accelerated by turbulent fast magnetosonic waves ("fast waves") via transit-time-damping (TTD) interactions. (In…
The solar wind is typically categorized as fast and slow based on the measured speed ($v_\mathrm{sw}$). The separation between these two regimes is often set between 400 and 600 km/s without a rigorous definition. Observations of the solar…
A rigorous analytical study of the dispersion relations of weakly amplified transverse fluctuations with wave vectors ($\vec{k}\parallel \vec{B}$) parallel to the uniform background magnetic field $\vec{B}$ in an anisotropic bi-Maxwellian…
Observations reveal nearly power-law spectra of magnetic and density plasma fluctuations at subproton scales in the solar wind, which indicates the presence of a turbulent cascade. We discuss the three-field and two-field models for…
We introduce a new solar energetic particle (SEP) transport code that aims at studying the effects of different solar wind configurations on SEP events. We focus on the influence of varying solar wind velocities on the energy changes of…
We present numerical simulations of reduced magnetohydrodynamic (RMHD) turbulence in a magnetic flux tube at the center of a polar coronal hole. The model for the background atmosphere is a solution of the momentum equation, and includes…
We present results from a kinetic model of collisionless gyrotropic coronal hole protons heated by cyclotron and Landau resonant dissipation of critically balanced kinetic Alfv\'en waves. The model incorporates the kinetic effects of…
Context. The origin of the heating of the solar atmosphere is still an unsolved problem. As the photosphere and chromosphere radiate more energy than the solar corona, it is challenging but important to reveal all the mechanisms that…
X-ray observations provide important and valuable insights into the acceleration and propagation of nonthermal electrons during solar flares. Improved X-ray spectral analysis requires a deeper understanding of the dynamics of energetic…
The relationship between a decaying strong turbulence and kinetic instabilities in a slowly expanding plasma is investigated using two-dimensional (2-D) hybrid expanding box simulations. We impose an initial ambient magnetic field…
A comprehensive understanding of solar coronal heating and charged particle acceleration remains one of the most critical challenges in space and astrophysical plasma physics. In this study, we explore the contribution of Alfv\'en waves,…
Remote sensing observations of coronal holes show that heavy ions are hotter than protons and their temperature is anisotropic. In-situ observations of fast solar wind streams provide direct evidence for turbulent Alfv\'en wave spectrum,…
In situ measurements of kinetic scale current sheets in the solar wind show that they are often approximately force-free although the plasma beta is of order one. They frequently display systematic asymmetric and anti-correlated spatial…
The heating of ions and electrons due to turbulent dissipation plays a crucial role in the thermodynamics of the solar wind and other plasma environments. Using magnetic field and thermal plasma observations from the first two perihelia of…
Enhancement of minor ions such as $^3$He and heavy ions in flare-associated solar energetic particle (SEP) events remains one of the major puzzles in heliophysics. In this work, we use 3D hybrid simulations (kinetic protons and fluid…
Following recent work, we discuss waves in a warm ideal two-fluid plasma consisting of electrons and ions starting from a completely general, ideal two-fluid dispersion relation. The plasma is characterised by five variables: the electron…