Studies of waves during asymmetric reconnection in laboratory and space

POSTER

Abstract

Wave activities during asymmetric reconnection have been studied by directly comparing data from the Magnetic Reconnection Experiment (MRX) with data from the Magnetospheric Multiscale (MMS). The power spectrum near separatrices on the low-density (magnetosphere) side shows remarkable similarities. Regarding fluctuations driven by lower hybrid drift instabilities (LHDI), it shows broad spectrum with the energy concentrated mostly below the lower-hybrid frequency. The free energy source of LHDI is the diamagnetic current by the strong density gradient near the separatrix region. The whistler waves show a power spectrum concentrated around half of the electron cyclotron frequency ($0.5f_{ce}$). In MMS, they propagate mostly parallel to the field line toward the X-line with a relatively high phase velocity ($\sim5\times10^7$ m/s). The whistler waves are also observed in the exhaust region and near the electron diffusion region (EDR). However, they become intermittent and with the frequency higher than $0.5f_{ce}$ in the exhaust region and higher than $0.5f_{ce}$ near the EDR. The dominant wave vector satisfies $kd_e\sim1$ for all cases. Possible excitation mechanisms for the observed whistler waves are discussed.

Authors

  • Jongsoo Yoo

    Princeton Plasma Physics Laboratory, Princeton Plasma Phys Lab, Princeton Plasma Physics Laboratory, Princeton University

  • Evan Yerger

    Princeton Plasma Phys Lab

  • Jonathan Jara-Almonte

    Princeton Plasma Physics Laboratory, Princeton Plasma Phys Lab

  • Masaaki Yamada

    Princeton Plasma Physics Laboratory, Princeton Plasma Phys Lab, Princeton Plasma Physics Laboratory, Princeton University

  • Hantao Ji

    Princeton U., PPPL, princeton university, Princeton Plasma Physics Laboratory, Princeton Plasma Phys Lab, Princeton Plasma Physics Laboratory, Princeton University

  • Will Fox

    PPPL, Princeton Plasma Physics Laboratory, Princeton Plasma Phys Lab, Princeton Plasma Physics Laboratory, Princeton University

  • Li-Jen Chen

    Goddard Space Flight Center; University of Maryland at College Park, University of Maryland College Park, Goddard Space Flight Center, NASA/Goddard Space Flight Center, University of Maryland at College Park, University of Maryland, College Park, UMD/NASA GSFC