Turbulent magneto-genesis in a collisionless plasma
  We investigate an efficient mechanism for generating magnetic fields in
turbulent, collisionless plasmas. By using fully kinetic, particle-in-cell
simulations of an initially non-magnetized plasma, we inspect the genesis of
magnetization, in a nonlinear regime. The complex motion is initiated via a
Taylor-Green vortex, and the plasma locally develops strong electron
temperature anisotropy, due to the strain tensor of the turbulent flow.
Subsequently, in a domino effect, the anisotropy triggers a Weibel instability,
localized in space. In such active wave-particle interaction regions, the
magnetic field seed grows exponentially and spreads to larger scales due to the
interaction with the underlying stirring motion. Such a self-feeding process
might explain magneto-genesis in a variety of astrophysical plasmas, wherever
turbulence is present.
