Search Publications
Test of Shi et al. method to infer the magnetic reconnection geometry from spacecraft data: MHD simulation with guide field and antiparallel kinetic simulation
Hesse, M.; Birn, J.; Drake, J. F. +3 more
When analyzing data from an array of spacecraft (such as Cluster or MMS) crossing a site of magnetic reconnection, it is desirable to be able to accurately determine the orientation of the reconnection site. If the reconnection is quasi-two dimensional, there are three key directions, the direction of maximum inhomogeneity (the direction across th…
Electron dynamics in the reconnection ion diffusion region
Fazakerley, A. N.; Daly, P. W.; Nakamura, R. +4 more
We investigate and compare Cluster observations of electron dynamics in different locations of the ion diffusion region for magnetic reconnection in the Earth's magnetotail. On the basis of the 2-D reconstructed magnetic field map from Cluster 1 (C1), we pinpoint that the observed Hall field is ∼6000 km (∼9 ion inertial lengths) away from the magn…
Location of the magnetodisk in the nightside outer magnetosphere of Saturn near equinox based on ion densities
Thomsen, M.; Szego, K.; Bebesi, Z. +4 more
We investigate ion densities derived from measurements by the Cassini Plasma Spectrometer, to determine how these ions are distributed around the magnetodisk of Saturn. The magnetodisk is a variable plasma structure, here we fitted the simple structural model of Arridge et al. (2011) as a reference for the location of the central line of the magne…
Inner magnetosphere currents during the CIR/HSS storm on July 21-23, 2009
Runov, A.; Ganushkina, N. Y.; Dubyagin, S. +2 more
Modeling results of the configuration of the inner magnetosphere current systems, namely, the ring current and the near-Earth tail current, during the July 21-23, 2009 CIR/HSS storm event are presented. We use two different modeling approaches, magnetic field modeling and particle modeling. We perform the magnetospheric magnetic field modeling wit…
The orientation and current density of the magnetotail current sheet: A statistical study of the effect of geomagnetic conditions
Lester, M.; Milan, S. E.; Fear, R. C. +2 more
We examine the orientation and current density of the current sheet during current sheet crossings from Cluster's 2001-2007 tail seasons. The curlometer technique is used to estimate the current density and is combined with Minimum Variance Analysis (MVA) to calculate the direction of the current sheet normal. The SYM-H and AE indices at the time …
Characterizing the limitations to the coupling between Saturn's ionosphere and middle magnetosphere
Ray, L. C.; Galand, M.; Fleshman, B. L. +1 more
Observations of Saturn's ultraviolet and infrared aurora show structures that, when traced along the planetary magnetic field, map to the inner, middle, and outer magnetosphere. From low to high latitudes the structures seen in the UV are the Enceladus footprint, which maps to an equatorial radius of 4 RS (Saturn radii); a diffuse emiss…
External triggering of plasmoid development at Saturn
Winglee, R. M.; Paty, C. S.; Harnett, E. M. +1 more
The Cassini spacecraft has encountered multiple plasmoids in Saturn's magnetotail thought to be produced by tail reconnection. However, single spacecraft measurements make it difficult to determine plasmoid size, where they form, the composition, and the geometry of the plasma sheet when plasmoids are produced. This paper examines these issues usi…
Statistical ring current of Saturn
Carbary, J. F.; Arridge, C. S.; Achilleos, N.
The statistical ring current of Saturn has been determined from the curl of the median magnetic field derived from over 5 years of observations of the Cassini magnetometer. The main issue addressed here is the calculation of the statistical ring current of Saturn by directly computing, for the first time, the symmetrical part of the ring current J…
Dynamic modeling of cusp ion structures
Raeder, J.; Trattner, K. J.; Connor, H. J.
Dispersed ion structures observed near the magnetosphere cusps have long been used to infer locations and properties of reconnection at the Earth's magnetopause. However, observations are often difficult to interpret since spacecraft move relative to a cusp ion structure, creating temporal and spatial ambiguity in the observations. Models of cusp …
Temporal evolution and electric potential structure of the auroral acceleration region from multispacecraft measurements
Dandouras, I.; Lucek, E.; Fazakerley, A. N. +12 more
Bright aurorae can be excited by the acceleration of electrons into the atmosphere in violation of ideal magnetohydrodynamics. Modeling studies predict that the accelerating electric potential consists of electric double layers at the boundaries of an acceleration region but observations suggest that particle acceleration occurs throughout this re…