Related papers: Firehose constraints for the solar wind supratherm…
Despite extensive observational and theoretical efforts, the physical processes responsible for shaping the diversity of accelerated electron spectra observed in solar flares remain poorly understood. We use 2D particle-in-cell (PIC)…
We present for the first time the joint distribution of electron heat flux and electron plasma beta, and the joint distribution of core electron drift velocity and electron plasma beta using a statistically large dataset of solar wind…
Using hybrid-kinetic particle-in-cell simulation, we study the evolution of an expanding, collisionless, magnetized plasma in which strong Alfv\'enic turbulence is persistently driven. Temperature anisotropy generated adiabatically by the…
We investigate the scattering of strahl electrons by microinstabilities as a mechanism for creating the electron halo in the solar wind. We develop a mathematical framework for the description of electron-driven microinstabilities and…
Using 2D particle-in-cell (PIC) plasma simulations we study electron acceleration by temperature anisotropy instabilities, assuming conditions typical of above-the-loop-top (ALT) sources in solar flares. We focus on the long-term effect of…
Recent statistical studies of observational data unveil relevant correlations between whistler fluctuations and the anisotropic electron populations present in space plasmas, e.g., solar wind and planetary magnetospheres. Locally, whistlers…
Despite the fact that electrons observed in situ in space plasmas have three major components-the quasi-thermal core, suprathermal halo, and strahl-the analysis of instabilities triggered by kinetic, velocity-space anisotropies (such as…
The preacceleration of electrons through reflection and shock drift acceleration (SDA) is essential for the diffusive shock acceleration (DSA) of nonthermal electrons in collisionless shocks. Previous studies suggested that, in weak…
Context. The presence of a magnetic guide field induces several types of anisotropy in solar wind turbulence. The energy cascade rate between scales in the inertial range depends strongly on the direction of this magnetic guide field,…
At kinetic scales in the solar wind, instabilities transfer energy from particles to fluctuations in the electromagnetic fields while restoring plasma conditions towards thermodynamic equilibrium. We investigate the interplay between…
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,…
Among the fundamental and most challenging problems of laboratory, space, and astrophysical plasma physics is to understand the relaxation processes of nearly collisionless plasmas toward quasi-stationary states; and the resultant states of…
Recent observations of the solar wind ions by the SPAN-I instruments on board the Parker Solar Probe (PSP) spacecraft at solar perihelia (Encounters) 4 and closer find ample evidence of complex anisotropic non-Maxwellian velocity…
Weakly collisional plasmas dynamically develop pressure anisotropies with respect to the magnetic field. These anisotropies trigger plasma instabilities at scales just above the ion Larmor radius \rho_i and much below the mean free path…
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…
We study wave instability in an collisionless, rarefied hot plasma (e.g. solar wind or corona). We consider the anisotropy produced by the magnetic field, when the thermal gas pressures across and along the field become unequal. We apply…
The formation of the observed core-halo feature in the solar wind electron velocity distribution function is a long-time puzzle. In this letter based on the current knowledge of nanoflares we show that the nanoflare-accelerated electron…
We analyze measured proton and electron temperatures in the high-speed solar wind in order to calculate the separate rates of heat deposition for protons and electrons. When comparing with other regions of the heliosphere, the fast solar…
Where and under what conditions the transfer of energy between electromagnetic fields and particles takes place in the solar wind remains an open question. We investigate the conditions that promote the growth of kinetic instabilities…
There have been several ideas proposed to explain how the Sun's corona is heated and how the solar wind is accelerated. Some models assume that open magnetic field lines are heated by Alfven waves driven by photospheric motions and…