Modulational Instability, Mode Conversion, and Radio Emission
in the Magnetized Pair Plasma of Pulsars
J. C. Weatherall
A theoretical analysis of coupled mode equations describes the evolution of
plasma wave turbulence in the strongly magnetized pair plasma of the pulsar
polar cap. The onset of turbulence is a modulational instability of a
large amplitude electrostatic wave. Numerical solution follows the
nonlinear evolution towards a strongly turbulent state characterized by the
multi-dimensional collapse of wave packets. The turbulence generates
electromagnetic modes which can escape the plasma. The modulational conversion
process provides a fairly simple scenerio for pulsar emission: an
electrostatic plasma wave instability and the subsequent modulational
mode coupling to escaping radiation.
STATUS: submitted to Ap.J.
return to Publications page