Francesco Califano

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It is shown that the pattern of current layers formed within a magnetic island in the nonlinear phase of magnetic field line reconnection in a collisionless two-dimensional fluid plasma is subject to the onset of a secondary instability, the effect of which increases with decreasing electron temperature. In the cold electron limit the saturation of the(More)
We present a numerical scheme for the integration of the Vlasov–Maxwell system of equations for a non-relativistic plasma, in the hybrid approximation, where the Vlasov equation is solved for the ion distribution function and the electrons are treated as a fluid. In the Ohm equation for the electric field, effects of electron inertia have been retained, in(More)
With the help of 2D-3V (two dimensional in space and three dimensional in velocity) Vlasov simulations we show that the magnetic field generated by the electromagnetic current filamentation instability develops magnetic islands due to the onset of a fast reconnection process that occurs on the electron dynamical time scale. This process is relevant to(More)
The nonlinear evolution of a Hamiltonian magnetic field line reconnection in a two-dimensional fluid plasma leads to a macroscopic equilibrium with a finite-size island and fine-scale spatial structures. The latter arise from the phase mixing of the Lagrangian invariant fields. This equilibrium is the analog of the Bernstein-Greene-Kruskal equilibrium(More)
We here discuss the emergence of quasistationary states (QSS), a universal feature of systems with long-range interactions. With reference to the Hamiltonian mean-field model, numerical simulations are performed based on both the original N-body setting and the continuum Vlasov model which is supposed to hold in the thermodynamic limit. A detailed(More)
The plasma response to the injection of a propagating purely electrostatic wave of finite amplitude is investigated by means of a kinetic code which solves the Vlasov equations for electrons and ions in the three-dimensional (one spatial and two in velocity, 1D2V) phase space, self-consistently coupled to the Maxwell equations. The plasma is uniformly(More)
We present three-dimensional, fully relativistic, fluid simulations of the dynamics of inhomogeneous counter streaming beams with the aim of understanding the magnetic structures that can be expected to form as a consequence of the development of the so-called Weibel instability. Ringlike structures in the transverse direction are generated as a consequence(More)
A one-dimensional open boundary Vlasov code is used in order to investigate the propagation of a short proton beam through a plasma slab. Collisionless regimes are assumed, where the interaction between the beam and the plasma occurs due to the self-consistent, collective, electric field. Both charge compensated (by an accompanying electron cloud) and(More)
The generation of a coherent ion flow due to the injection in a plasma of a purely electrostatic wave of finite amplitude, propagating at right angle with the ambient uniform magnetic field, is investigated making use of a kinetic code which solves the fully nonlinear Vlasov equations for electrons and ions, coupled with the Maxwell equations, in one(More)