Princeton Center for Heliophysics Seminar

The solar wind is a classic example of a turbulent plasma. At moderate scales (larger than ion-kinetic scales) turbulent fluctuations in the solar wind are often Alfvénic in character, meaning that their magnetic and flow velocity fluctuations are proportional to each other. However, observations of the solar wind have shown that there is a significant difference in the energy in the velocity fluctuations and the normalized magnetic field fluctuations. This difference, called the residual energy, should be zero for linear Alfvén waves, but is consistently observed to be negative in the solar wind, with magnetic fluctuations dominating. This work investigates the energy partition of strong three-wave interactions as a building block of interactions in the turbulent cascade. Preliminary results from an experimental campaign on LAPD studying three-wave interactions of Alfvén waves in an MHD-like regime will be presented.