Disconnection in the Magnetotail

The unique orbit of IBEX, which takes it out to ~50 Earth Radii provides a singularly unique perspective from which to image the magnetosphere. IBEX has provided the first images of the ENA emissions from the night side magnetosphere and from the Earth’s plasma sheet. IBEX images from two IBEX orbits show a significant intensification that may indicate a near–Earth (~10 RE behind the Earth) disconnection event. IBEX observations indicate the simultaneous addition of both a hot (several keV) and cold component during the intensification. The hot component may signify the plasma energization driven by magnetic reconnection. IBEX observations have also provided some of the first ENA images of the magnetospheric cusps and subsolar magnetopause. The IBEX discoveries and observations of the magnetosphere reveal never before observed dynamics of the magnetotail. The overall structure of the magnetosphere revealed by IBEX enables fundamental advances in our understanding of the magnetosphere’s response to changing conditions of solar wind and the internal magnetospheric dynamics involving the interplay between Earth’s magnetic field and plasma. These advances are important both for understanding the impacts of space storms on geospace and for basic understanding of heliospheric plasma.

References:

Petrinec, S.M., M.A. Dayeh, H.O. Funsten, S.A. Fuselier, D. Heirtzler, P. Janzen, H. Kucharek, D.J. McComas, E. Möbius, T.E. Moore, D.B. Reisenfeld, N.A. Schwadron, K.J. Trattner, and P. Wurz, Neutral atom imaging of the magnetospheric cusps, J. Geophys. Res., 116, A07203, doi: 10.1029/2010JA016357, 2011.

McComas, D.J., M.A. Dayeh, H.O. Funsten, S.A. Fuselier, J. Goldstein, J.–M. Jahn, P. Janzen, D.G. Mitchell, S.M. Petrinec, D.B. Reisenfeld, and N.A. Schwadron, First IBEX observations of the terrestrial plasma sheet and a possible disconnection event, J. Geophys. Res., 116, A02211, doi: 10.1029/2010JA016138, 2011.

McComas, D.J., N. Buzulukova, M.G. Connors, M.A. Dayeh, J. Goldstein, H.O. Funsten, S. Fuselier, N.A. Schwadron, and P. Valek, TWINS and IBEX ENA imaging of the 5 April 2010 substorm, in press, J. Geophys. Res., 2011.

Fuselier, S.A., H.O. Funsten, D. Heirtzler, P. Janzen, H. Kucharek, D.J. McComas, E. Moebius, T.E. Moore, S.M. Petrinec, D.B. Reisenfeld, N.A. Schwadron, K.J. Trattner, and P. Wurz, Energetic neutral atoms from the Earth’s subsolar magnetopause, Geophys. Res. Lett., 37, L13101, doi:10.1029/2010GL044140, 2010.