Electrostatic coherent structures generation by local heating in a collisionless plasma

We propose a new mechanism for the generation of electrostatic coherent structures and Langmuir fluctuations in a stratified plasma. The model is base on open boundary 1D Vlasov simulations where heated electrons are injected by applying a temporal continuous periodic modification of the width of the electron distribution function at one boundary of the simulation box. To our knowledge, that is the first time that a "localized heating" mechanism is studied as a driver for the development of bi(multi)polar electric field with their associated electron density holes and vortices in the phase space. After the development of many electrostatic coherent structures, the injected fast particles are free to move along their ballistic limit, while electrons moving at nearly, or less than, the thermal speed are diffused in phase space by the local fields. (c) 2007 Elsevier B.V. All rights reserved