Electrostatic ion perturbations in kinematically complex shear flows

Self-sustaining vortex perturbations in smooth shear flows

The nonlinear dynamics of coherent circular/elliptical cyclonic and anticyclonic vortices in plane flow with constant shear is investigated numerically using a dealiased Fourier pseudospectral code. The flow is asymptotically linearly stable, but is highly non-normal, allowing perturbations to gain energy transiently from the background shear flow. This linear transient growth interplays with n...

Electrostatic Ion-cyclotron Waves Driven by Parallel Velocity Shear

Using a fluid treatment, it is shown that electrostatic waves with angular frequencies ~ ωci (ion cyclotron frequency) propagating at large angles to the ambient magnetic field can be excited in a magnetized plasma by perpendicular shear in the magnetic field aligned plasma flow. The role of density gradients in determining the stability of sheardriven EIC modes is also considered. PACS numbers...

Chaos in Shear Flows

Reciprocal interparticle attraction in complex plasmas with cold ion flows

The paper investigates, in the framework of the kinetic approach, the linear screening of a point non-absorbing charge in a homogeneous collisionless plasma with cold ion flow. The velocity distribution of ions far from the charge is assumed to be a shifted Maxwellian distribution with infinitesimal thermal velocity and finite flow velocity, and the electron component is considered as a homogen...

Subcritical dynamos in shear flows

1 Laboratoire d’Astrophysique de Toulouse-Tarbes, Université de Toulouse, CNRS, 14 avenue Edouard Belin, F-31400 Toulouse, France 2 Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA, United Kingdom 3 Laboratoire d’hydrodynamique (LadHyX), CNRS – École polytechnique, 91128 Palaiseau cedex, France