Thomson scattering measurements of ion-acoustic waves driven by ion-acoustic decay instabilities

Abstract

A large angle, multichannel ultraviolet Thomson scattering diagnostic was developed to study ion-acoustic waves in laser-produced high-density plasma. The time evolution of the spectral density function of the ion-acoustic wave (IAW) was measured by the scattering system. When a weak IAW was excited, the measured spectrum had a well-defined narrow peak, which was consistent with plasma parameters predicted by computer simulations assuming an electron transport flux limit of 0.1. The spectrum of the IAW was quite different, and broad, when it was excited strongly.