Collaborative Research: GEM--Multi-harmonic Whistler Waves, Their Origin and Contribution to Electron Scattering

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

Multi-harmonic whistler waves are capable of scattering and accelerating electrons to high speeds in the Earth’s inner magnetosphere and other plasma environments. Understanding the origins of these waves and how they interact with electrons is important for forecasting and predicting space weather and its effects on sensitive systems such as satellites and space craft. The project supports three early career scientists and undergraduate research opportunities. There are three main objectives to this project: 1) What plasma parameters determine the possibility and rate of the whistler wave energy cascade to multi-harmonic frequencies of the electrostatic component? 2) What plasma parameters determine the possibility and rate of the whistler wave energy cascade to multi-harmonic frequencies of the electromagnetic components? 3) How does the whistler wave energy cascade to higher frequencies influence the efficiency of whistler waves in accelerating electrons? This will be accomplished by analysis of multi-harmonic whistler wave measurements from the Van Allen Probes and the Time History of Events and Macroscale Interactions during Substorms mission in the Earth’s inner magnetosphere and by the Magnetospheric Multiscale Mission in the day-side magnetopause reconnection. Spacecraft observations will be combined with numerical simulations (multi-fluid magnetohydrodynamic code) of whistler wave steepening and test-particle simulations of electron interaction with these whistler waves. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.