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arXiv · 1905.02953

ViDA: a Vlasov-DArwin solver for plasma physics at electron scales

Oreste Pezzi·Giulia Cozzani·Francesco Califano·Francesco Valentini·Massimiliano Guarrasi·Enrico Camporeale·Gianfranco Brunetti·Alessandro Retinò·Pierluigi Veltri
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Abstract

We present a Vlasov-DArwin numerical code (ViDA) specifically designed to address plasma physics problems, where small-scale high accuracy is requested even during the non linear regime to guarantee a clean description of the plasma dynamics at fine spatial scales. The algorithm provides a low-noise description of proton and electron kinetic dynamics, by splitting in time the multi-advection Vlasov equation in phase space. Maxwell equations for the electric and magnetic fields are reorganized according to Darwin approximation to remove light waves. Several numerical tests show that ViDA successfully reproduces the propagation of linear and nonlinear waves and captures the physics of magnetic reconnection. We also discuss preliminary tests of the parallelization algorithm efficiency, performed at CINECA on the Marconi-KNL cluster. ViDA will allow to run Eulerian simulations of a non-relativistic fully-kinetic collisionless plasma and it is expected to provide relevant insights on important problems of plasma astrophysics such as, for instance, the development of the turbulent cascade at electron scales and the structure and dynamics of electron-scale magnetic reconnection, such as the electron diffusion region.

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Oreste Pezzi, Giulia Cozzani, Francesco Califano, Francesco Valentini, Massimiliano Guarrasi, Enrico Camporeale, Gianfranco Brunetti, Alessandro Retinò, Pierluigi Veltri. 2019-05-08. ViDA: a Vlasov-DArwin solver for plasma physics at electron scales. https://doi.org/10.1017/s0022377819000631

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