Vlasov simulations of Langmuir Electrostatic Decay and consequences for Type III observations

TL;DR

This paper uses Vlasov-Poisson simulations to study Langmuir electrostatic decay, revealing its role in generating type III solar radio emissions and aligning with recent spacecraft observations.

Contribution

It provides the first detailed simulation analysis of Langmuir electrostatic decay considering localized wave packets under equal electron and ion temperatures.

Findings

Simulation results match STEREO observations of electrostatic decay during type III bursts.

Electrostatic decay facilitates energy transfer from Langmuir waves to ion acoustic fluctuations.

Supports the hypothesis that electrostatic decay is a key step in type III radio emission generation.

Abstract

The electrostatic decay enables energy transfer from a finite amplitude Langmuir to a backscattered daughter Langmuir wave and ion acoustic density fluctuations. This mechanism is thought to be a first step for the generation of type III solar radio emissions at twice the plasma frequency. The electrostatic decay is here investigated through Vlasov-Poisson simulations by considering Langmuir localized wave packets in the case Te = Tp. Simulation results are found to be in good agreement with recently reported observations from the STEREO mission of the electrostatic decay of beam-driven Langmuir waves during a type III burst.