Low- altitude electron acceleration due to multiple flow bursts in themagnetotail

• Published in: Geophysical research letters Vol. 41; no. 3; p. 777
• Main Authors: Nakamura, R., Karlsson, Tomas, Hamrin, M., Nilsson, H., Marghitu, O., Amm, O., Bunescu, C., Constantinescu, V., Frey, H. U., Keiling, A., Semeter, J., Sorbalo, E., Vogt, J., Forsyth, C., Kubyshkina, M. V.
• Format: Journal Article
• Language: English
• Published: 16.02.2014
• Subjects: Alfven waves; field-aligned current; magnetosphere-ionosphere coupling; multiple flow burst
• ISSN: 1944-8007; 0094-8276
• DOI: 10.1002/2013GL058982

At 10:00 UT on 25 February 2008, Cluster 1 spacecraft crossed the near-midnight auroral zone, at about 2R(E) altitude, while two of the Time History of Events and Macroscale Interactions During Substorms (THEMIS) spacecraft, THD and THE, observed multiple flow bursts on the near-conjugate plasma sheet field lines. The flow shear pattern at THEMIS was consistent with the vortical motion at duskside of a localized flow channel. Coinciding in time with the flow bursts, Cluster 1 observed bursts of counterstreaming electrons with mostly low energies (441eV), accompanied by short time scale (<5s) magnetic field disturbances embedded in flow-associated field-aligned current systems. This conjugate event not only confirms the idea that the plasma sheet flows are the driver of the kinetic Alfven waves accelerating the low-energy electrons but is a unique observation of disturbances in the high-altitude auroral region relevant to the multiple plasma sheet flows. Key Points <list list-type="bulleted"> <list-item id="grl51326-li-0001">First observation of multiple flow signatures on near-conjugate flux tubes <list-item id="grl51326-li-0002">Low-energy electron profile suggests Alfvenic acceleration due to fast flow <list-item id="grl51326-li-0003">Multiple flow bursts are obtained to extend over large radial distance in tail