title: Ion-scale secondary flux ropes generated by magnetopause reconnection as resolved by MMS.
abstract: New Magnetospheric Multiscale (MMS) observations of small-scale (~7 ion inertial length radius) flux transfer events (FTEs) at the dayside magnetopause are reported. The 10 km MMS tetrahedron size enables their structure and properties to be calculated using a variety of multispacecraft techniques, allowing them to be identified as flux ropes, whose flux content is small (~22 kWb). The current density, calculated using plasma and magnetic field measurements independently, is found to be filamentary. Intercomparison of the plasma moments with electric and magnetic field measurements reveals structured non-frozen-in ion behavior. The data are further compared with a particle-in-cell simulation. It is concluded that these small-scale flux ropes, which are not seen to be growing, represent a distinct class of FTE which is generated on the magnetopause by secondary reconnection.
authors.affiliation: Blackett Laboratory Imperial College London London UK.
authors.forename: J P
authors.initials: JP
authors.lastname: Eastwood
authors.affiliation: Space Sciences Laboratory University of California Berkeley California USA.
authors.forename: T D
authors.initials: TD
authors.lastname: Phan
authors.affiliation: Department of Physics and Astronomy West Virginia University Morgantown West Virginia USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Cassak
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA; Department of Astronomy University of Maryland College Park Maryland USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Gershman
authors.affiliation: Department of Physics and Astronomy University of Delaware Newark Delaware USA.
authors.forename: C
authors.initials: C
authors.lastname: Haggerty
authors.affiliation: Department of Physics Mahidol University Bangkok Thailand.
authors.forename: K
authors.initials: K
authors.lastname: Malakit
authors.affiliation: Department of Physics and Astronomy University of Delaware Newark Delaware USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Shay
authors.affiliation: Blackett Laboratory Imperial College London London UK.
authors.forename: R
authors.initials: R
authors.lastname: Mistry
authors.affiliation: Space Sciences Laboratory University of California Berkeley California USA.
authors.forename: M
authors.initials: M
authors.lastname: Øieroset
authors.affiliation: Department of Earth, Planetary and Space Sciences University of California Los Angeles California USA.
authors.forename: C T
authors.initials: CT
authors.lastname: Russell
authors.affiliation: Department of Climate and Space Sciences and Engineering University of Michigan Ann Arbor Michigan USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Slavin
authors.affiliation: Institute for the Study of Earth, Oceans and Space University of New Hampshire Durham New Hampshire USA.
authors.forename: M R
authors.initials: MR
authors.lastname: Argall
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA; Department of Astronomy University of Maryland College Park Maryland USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Avanov
authors.affiliation: Southwest Research Institute San Antonio Texas USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Burch
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA; Department of Astronomy University of Maryland College Park Maryland USA.
authors.forename: L J
authors.initials: LJ
authors.lastname: Chen
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Dorelli
authors.affiliation: Laboratory for Atmospheric and Space Physics University of Colorado Boulder Boulder Colorado USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Ergun
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA.
authors.forename: B L
authors.initials: BL
authors.lastname: Giles
authors.affiliation: Swedish Institute of Space Physics Uppsala Sweden.
authors.forename: Y
authors.initials: Y
authors.lastname: Khotyaintsev
authors.affiliation: Institut de Recherche en Astrophysique et Planétologie Université de Toulouse Toulouse France; Centre National de la Recherche Scientifique, UMR 5277 Toulouse France.
authors.forename: B
authors.initials: B
authors.lastname: Lavraud
authors.affiliation: School of Electrical Engineering Royal Institute of Technology Stockholm Sweden.
authors.forename: P A
authors.initials: PA
authors.lastname: Lindqvist
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA.
authors.forename: T E
authors.initials: TE
authors.lastname: Moore
authors.affiliation: Space Research Institute Austrian Academy of Sciences Graz Austria.
authors.forename: R
authors.initials: R
authors.lastname: Nakamura
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA.
authors.forename: W
authors.initials: W
authors.lastname: Paterson
authors.affiliation: Denali Scientific Healy Alaska USA.
authors.forename: C
authors.initials: C
authors.lastname: Pollock
authors.affiliation: Department of Earth, Planetary and Space Sciences University of California Los Angeles California USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Strangeway
authors.affiliation: Institute for the Study of Earth, Oceans and Space University of New Hampshire Durham New Hampshire USA; Southwest Research Institute San Antonio Texas USA.
authors.forename: R B
authors.initials: RB
authors.lastname: Torbert
authors.affiliation: NASA Goddard Space Flight Center Greenbelt Maryland USA; Department of Astronomy University of Maryland College Park Maryland USA.
authors.forename: S
authors.initials: S
authors.lastname: Wang
keywords: flux rope; magnetic reconnection; magnetopause; magnetospheric multiscale; secondary island