The magnetospheric multiscale (MMS) mission was launched by NASA in march 2015 to study magnetic reconnection in the earth's magnetosphere. The first phase of the mission focused on the dayside…

This federal contract award is for a research grant to The Regents of the University of Colorado, doing business as the University of Colorado Office of Contracts and Grants Division, to investigate the role of waves in magnetic reconnection as part of NASA's Magnetospheric Multiscale (MMS) mission. The MMS mission was launched in 2015 to study magnetic reconnection in the Earth's magnetosphere, with a focus on how electron and kinetic scale phenomena impact this process. The awarded grant will support research to identify the wave modes associated with dayside magnetic reconnection, determine their spatial distribution, and analyze signatures of turbulence in the diffusion regions and separatrices. This $130,294.19 grant does not have a set-aside designation and was awarded directly by the National Aeronautics and Space Administration Shared Services Center on September 11, 2018 with a performance period ending on August 31, 2020. As a U.S. state government entity and accredited public research university, the University of Colorado has extensive experience conducting fundamental research across science and engineering disciplines under federal grants and contracts.

The magnetospheric multiscale (MMS) mission was launched by NASA in march 2015 to study magnetic reconnection in the earth's magnetosphere. The first phase of the mission focused on the dayside magnetopause. The major focus of MMS is how electron and kinetic scale phenomena impact magnetic reconnection. One such example that warrants further investigation is the role of waves and plasma turbulence in mediating magnetic reconnection. Recent observations by MMS and other spacecraft have shown whistler waves that appear to propagate along the separatrix towards the x-line [graham ET AL., 2016; LE contel ET AL., 2016], and are associated with electron scale solitary structures [wilder ET AL., 2016A]. Near the ION diffusion region, beam mode and ION-cyclotron waves have been reported [zhou ET AL., 2016], and in the electron jet, buneman waves have been observed [khotyaintsev ET AL., 2016]. Additionally, MMS observed large-amplitude, parallel, electrostatic waves associated with mixing of cold and warm plasma near the electron diffusion region, as well as in dayside kelvin-helmholtz mixing regions [ergun ET AL., 2016A; wilder ET AL., 2016B]. Additionally, parallel electric fields associated with plasma turbulence have been reported [ergun ET AL., 2016], and when particlein- cell simulations are extended to 3-d, the separatrix and diffusion regions become turbulent [price ET AL., 2016]. So far, the waves associated with dayside reconnection and the role of turbulence have not been studied systematically, but through case studies. We propose to investigate the role of waves in magnetic reconnection for numerous encounters with the dayside separatrices, as well as the ION and (when available) electron diffusion regions. We will investigate the role of waves and turbulence in dayside magnetic reconnection by addressing the following three science questions: (1) what are the wave modes most frequently observed near the x-line of dayside magnetic reconnection? (2) where, with respect to the separatrices, diffusion regions, and stagnation point, do they occur, and do they propagate into the electron diffusion region? (3) how often do the diffusion regions and separatrices exhibit signatures of turbulence, including magnetic fluctuations and dissipative parallel electric fields? The above questions will be addressed using data from NASA's MMS mission. These data are critical for the proposed research, as the mission was designed to skim the dayside magnetopause, and the tetrahedral formation allows US to resolve spatial and temporal phenomena near the diffusion regions and separatrices. Further, the high data rate when the spacecraft is in burst mode allows US to analyze waveform and spectral data in both the electromagnetic fields and particles, including distribution functions and moments. This will allow US to identify wave modes, analyze their propagation characteristics and perform stability analysis based on the ION and electron distributions. The curl of the measured magnetic field, as well as ION and electron velocity moments will be used to identify strong currents associated with reconnection, and the ION and electron diffusion regions will be identified by evaluating the frozenin condition through a comparison of the 3-d electric field measured by the electric field double probes (EDP) with the -VXB electric field measured by the fast plasma instrument (FPI) for both ions and electrons. Static spectra will also be computed using EDP data, combined fluxgate and search coil magnetic field data, and FPI moments, in a manner similar to analysis by stawarz ET AL. [2016]. This project will investigate an important physical phenomenon that impacts the interactions between the solar wind, magnetosphere and ionosphere. IT is therefore relevant to the goal of the recent decadal survey to "determine the dynamics and coupling of the earth's magnetosphere, ionosphere and atmosphere and their response to solar terrestrial impacts."