Investigation of the ion Weibel instability: hybrid kinetic simulations in support of laser-driven experiments at OMEGA
POSTER
Abstract
In astrophysical plasmas, high magnetic fields are commonplace but their origins and amplification processes responsible for generating them are not entirely understood. One candidate for the amplification of magnetic fields is the ion Weibel instability. Counter streaming plasma flows in the presence of seed fields form current filaments causing the initial magnetic field to grow. The nonlinear dynamics of current filaments are not understood, especially at late times, and theoretical predictions differ depending on what physics is included. Previous experiments have demonstrated the development of Weibel-generated current filaments from interpenetrating ion flows but have not recorded data at late enough times to differentiate between models. New experiments have been performed at OMEGA to observe the nonlinear dynamics of current filaments at later times (t >10ns). Interpretation of this data depends on our understanding of the experimental plasma conditions including the ion-ion collisionality, and resistivity. In this work, initial hybrid kinetic simulations of the latest experiments are presented to complement the single-position Thomson scattering measurements of plasma conditions, and to model the linear and subsequent nonlinear growth of the Weibel instability.
*This work was supported by the U.S. DOE NNSA Center of Excellence at MIT under Contract DE-NA0003868, NLUF and LLNL.
Presenters
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Niels Vanderloo
- Massachusetts Institute of Technology