TY - JOUR

T1 - Simultaneous Remote Observations of Intense Reconnection Effects by DMSP and MMS Spacecraft During a Storm Time Substorm

AU - Varsani, A.

AU - Nakamura, R.

AU - Sergeev, V. A.

AU - Baumjohann, W.

AU - Owen, C. J.

AU - Petrukovich, A. A.

AU - Yao, Z.

AU - Nakamura, T. K.M.

AU - Kubyshkina, M. V.

AU - Sotireli, T.

AU - Burch, J. L.

AU - Genestreti, K. J.

AU - Vörös, Z.

AU - Andriopoulou, M.

AU - Gershman, D. J.

AU - Avanov, L. A.

AU - Magnes, W.

AU - Russell, C. T.

AU - Plaschke, F.

AU - Khotyaintsev, Y. V.

AU - Giles, B. L.

AU - Coffey, V. N.

AU - Dorelli, J. C.

AU - Strangeway, R. J.

AU - Torbert, R. B.

AU - Lindqvist, P. A.

AU - Ergun, R.

PY - 2017/11/3

Y1 - 2017/11/3

N2 - During a magnetic storm on 23 June 2015, several very intense substorms took place, with signatures observed by multiple spacecraft including DMSP and Magnetospheric Multiscale (MMS). At the time of interest, DMSP F18 crossed inbound through a poleward expanding auroral bulge boundary at 23.5 h magnetic local time (MLT), while MMS was located duskward of 22 h MLT during an inward crossing of the expanding plasma sheet boundary. The two spacecraft observed a consistent set of signatures as they simultaneously crossed the reconnection separatrix layer during this very intense reconnection event. These include (1) energy dispersion of the energetic ions and electrons traveling earthward, accompanied with high electron energies in the vicinity of the separatrix; (2) energy dispersion of polar rain electrons, with a high-energy cutoff; and (3) intense inward convection of the magnetic field lines at the MMS location. The high temporal resolution measurements by MMS provide unprecedented observations of the outermost electron boundary layer. We discuss the relevance of the energy dispersion of the electrons, and their pitch angle distribution, to the spatial and temporal evolution of the boundary layer. The results indicate that the underlying magnetotail magnetic reconnection process was an intrinsically impulsive and the active X-line was located relatively close to the Earth, approximately at 16-18 RE.

AB - During a magnetic storm on 23 June 2015, several very intense substorms took place, with signatures observed by multiple spacecraft including DMSP and Magnetospheric Multiscale (MMS). At the time of interest, DMSP F18 crossed inbound through a poleward expanding auroral bulge boundary at 23.5 h magnetic local time (MLT), while MMS was located duskward of 22 h MLT during an inward crossing of the expanding plasma sheet boundary. The two spacecraft observed a consistent set of signatures as they simultaneously crossed the reconnection separatrix layer during this very intense reconnection event. These include (1) energy dispersion of the energetic ions and electrons traveling earthward, accompanied with high electron energies in the vicinity of the separatrix; (2) energy dispersion of polar rain electrons, with a high-energy cutoff; and (3) intense inward convection of the magnetic field lines at the MMS location. The high temporal resolution measurements by MMS provide unprecedented observations of the outermost electron boundary layer. We discuss the relevance of the energy dispersion of the electrons, and their pitch angle distribution, to the spatial and temporal evolution of the boundary layer. The results indicate that the underlying magnetotail magnetic reconnection process was an intrinsically impulsive and the active X-line was located relatively close to the Earth, approximately at 16-18 RE.

KW - Magnetic reconnection

KW - Magnetospheric Multiscale (MMS) mission

KW - Plasma sheet boundary layer (PSBL)

UR - http://www.scopus.com/inward/record.url?scp=85034576071&partnerID=8YFLogxK

U2 - 10.1002/2017JA024547

DO - 10.1002/2017JA024547

M3 - Article

AN - SCOPUS:85034576071

VL - 122

SP - 10891

EP - 10909

JO - Journal of Geophysical Research: Biogeosciences

JF - Journal of Geophysical Research: Biogeosciences

SN - 0148-0227

IS - 11

ER -