Related papers: A Model of Plasma Heating by Large-Scale Flow
It is well known that magnetic fields constrain motions of charged particles, impeding the diffusion of charged particles perpendicular to magnetic field direction. This modification of transport processes is of vital importance for a wide…
The solar atmosphere is dominated by loops of magnetic flux which connect the multi-million-degree corona to the much cooler chromosphere. The temperature and density structure of quasi-static loops is determined by the continuous flow of…
Cool stars like our Sun are surrounded by a million degree hot outer atmosphere, the corona. Since more than 60 years the physical nature of the processes heating the corona to temperatures well in excess of those on the stellar surface…
Decay in time of undriven weakly collisional kinetic plasma turbulence in systems large compared to the ion kinetic scales is investigated using fully electromagnetic particle-in-cell simulations initiated with transverse flow and magnetic…
The heating of the plasma in the solar atmosphere is discussed within both frameworks of fluid and kinetic drift wave theory. We show that the basic ingredient necessary for the heating is the presence of density gradients in the direction…
A large part of the hot corona consists of magnetically confined, bright plasma loops. These observed loops are in turn structured into bright strands. We investigate the relationship between magnetic field geometry, plasma properties and…
Magnetohydrodynamic (MHD) waves and/or the braiding of magnetic field lines are largely thought to be responsible for heating the solar corona, both being mechanisms which are driven by the Sun's photospheric magnetic field. Recent…
We investigate coronal heating and acceleration of the high- and low-speed solar wind in the open field region by dissipation of fast and slow magnetohydrodynamical (MHD) waves through MHD shocks. Linearly polarized \Alfven (fast MHD) waves…
Self-organization in continuous systems is associated with dissipative processes. In particular, for magnetized plasmas, it is known as magnetic relaxation, where the magnetic energy is converted into heat and kinetic energy of flow through…
We have measured the energy and dissipation of Alfvenic waves in the quiet Sun. A magnetic field was used to infer the location and orientation of the magnetic field lines along which the waves are expected to travel. The waves were…
I propose a new paradigm for solar coronal heating viewed as a self-regulating process keeping the plasma marginally collisionless. The mechanism is based on the coupling between two effects. First, coronal density controls the plasma…
Several models have been proposed to explain the formation of solar prominences, among which the evaporation--condensation model and the direct injection model are the most popular ones. In our previous study we proposed to unify these two…
Turbulence, magnetic reconnection, and shocks can be present in explosively unstable plasmas, forming a new electromagnetic environment, which we call here turbulent reconnection, and where spontaneous formation of current sheets takes…
A mechanism of self-heating of solar corona is pointed out. It is shown that the free energy available in the form of sheared flows gives rise to unstable electrostatic waves which accelerate the particles and heat them. The electrostatic…
X-ray observations of hot gas in galaxy clusters often show steeper temperature gradients across cold fronts -- contact discontinuities, driven by the differential gas motions. These sharp (a few kpc wide) surface brightness/temperature…
The energy production through thermo-nuclear fusion requires the confinement of the plasma into a bounded domain. In most of the cases, such configurations are obtained by using strong magnetic fields. Several models exist for describing…
We show that at large magnetic Prandtl numbers, the Lorentz force does work on the flow at small scales and drives fluid motions, whose energy is dissipated viscously. This situation is opposite to that in a normal dynamo, where the flow…
Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction…
Magnetic reconnection in the corona results in contracting flare loops, releasing energy into plasma heating and shocks. The hydrodynamic shocks so produced drive thermal conduction fronts (TCFs) which transport energy into the chromosphere…
Relaxation of braided coronal magnetic fields through reconnection is thought to be a source of energy to heat plasma in active region coronal loops. However, observations of active region coronal heating associated with an untangling of…