title: Evidence for an elongated (>60 ion skin depths) electron diffusion region during fast magnetic reconnection.
abstract: Observations of an extremely elongated electron diffusion region occurring during fast reconnection are presented. Cluster spacecraft in situ observations of an expanding reconnection exhaust reveal a broad current layer ( approximately 10 ion skin depths thick) supporting the reversal of the reconnecting magnetic field together with an intense current embedded at the center that is due to a super-Alfvénic electron outflow jet with transverse scale of approximately 9 electron skin depths. The electron jet extends at least 60 ion skin depths downstream from the X-line.
authors.affiliation: Space Sciences Laboratory, University of California, Berkeley, California 94720, USA.
authors.forename: T D
authors.initials: TD
authors.lastname: Phan
authors.forename: J F
authors.initials: JF
authors.lastname: Drake
authors.forename: M A
authors.initials: MA
authors.lastname: Shay
authors.forename: F S
authors.initials: FS
authors.lastname: Mozer
authors.forename: J P
authors.initials: JP
authors.lastname: Eastwood