HR: 0830h
AN: SM51B-0532 [PDF]
TI: The magnetopause transition: Cluster observations
AU: * Dunlop, M W
EM: m.dunlop@rl.ac.uk
AF: Rutherford Appleton Laboratory, Chilton, DIDCOT,
Oxfordshire, DIDCOT, Ox OX11 0QX
United Kingdom
AU: Hapgood, M
EM: m.hapgood@rl.ac.uk
AF: Rutherford Appleton Laboratory, Chilton, DIDCOT,
Oxfordshire, DIDCOT, Ox OX11 0QX
United Kingdom
AU: Lockwood, M
EM: m.lockwood@rl.ac.uk
AF: Rutherford Appleton Laboratory, Chilton, DIDCOT,
Oxfordshire, DIDCOT, Ox OX11 0QX
United Kingdom
AU: Fazakerley, A
EM: anf@mssl.ucl.ac.uk
AF: Mullard Space Science Laboratory, Holmbury St. Mary,
Dorking, Surrey, Dorking, Surrey
United Kingdom
AU: Owen, C
EM: cjo@mssl.ucl.ac.uk
AF: Mullard Space Science Laboratory, Holmbury St. Mary,
Dorking, Surrey, Dorking, Surrey
United Kingdom
AU: Balogh, A
EM: a.balogh@imperial.ac.uk
AF: Imperial College London, The Blackett Laboratory,
Imperial College, Prince Consort Road, London, SW7 2BW
United Kingdom
AU: Bosqued, J
EM: Jean-Michel.Bosqued@cesr.fr
AF: Centre d'tude Spatiale des Rayonnements, Dpartement systme solaire, 9 avenue du Colonel Roche Cedex
4, Toulouse, 31028
France
AB:
The transition parameter (TP, Hapgood and Bryant, 1992), for the magnetopause to magnetosheath traversal, reveals an
underlying order to magnetopause structure which is not readily seen in time series data because of rapid boundary motion
(temporal, as opposed to spatial, effects are better revealed in this re-ordering). The ordering works irrespective of the
presence of accelerated flows, wave motions or FTE signatures, but it is not known how the TP is related to spatial
boundary-normal distance. Previous application of the TP to AMPTE-UKS and -IRM data identified the total LLBL thickness to be
of order 1500 km. The form of the TP variation in boundary aligned co-ordinates (and specifically with normal distance) is
likely to be different in each case, however. Since knowledge of boundary orientation, thickness and motion can independently
scale the plasma and field signatures across the boundary layer, the four point Cluster data allow us to compare the TP
ordering in the context of well defined boundary behaviour and also allows us to look at the effects of reconnection site
motions. We investigate a number of magnetopause crossings observed by Cluster on different spatial scales.
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2740 Magnetospheric configuration and dynamics
DE: 2794 Instruments and techniques
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting