Search Publications
On the origin of near-radial magnetic fields in the heliosphere: Numerical simulations
Riley, Pete; Gosling, J. T.
Deviations from the direction of the "Parker spiral" can be found in in situ measurements of the interplanetary magnetic field on essentially all scales. One intriguing subset is the intervals of near-radial magnetic field, lasting for many hours. Some such intervals are obviously associated with coronal mass ejections, while others appear to be e…
Interaction between coronal mass ejections and the solar wind
Breen, A. R.; Bisi, M. M.; Fallows, R. A. +3 more
Observations suggest that the interplanetary extensions of coronal mass ejections (iCMEs) may be accelerated or decelerated in their passage through the solar wind. Interplanetary scintillation measurements (IPS) can detect the passage of iCMEs beyond the field of view of the Large-Angle and Spectrometric Coronagraph coronagraphs and can provide i…
Chorus source properties that produce time shifts and frequency range differences observed on different Cluster spacecraft
Gurnett, D. A.; Pickett, J. S.; SantolíK, O. +3 more
We present an explanation of frequency range differences and time shifts between corresponding chorus elements of whistler mode chorus which have been recently observed on multiple Cluster spacecraft. We show that a nonmoving or quasi-static source that emits waves in a relatively narrow interval of wave normal angles and that varies both the wave…
Electron periodicities in Saturn's outer magnetosphere
Krupp, N.; Krimigis, S. M.; Mitchell, D. G. +1 more
The Magnetospheric Imaging Instrument/Low-Energy Magnetospheric Measurements Sensor (MIMI/LEMMS) instrument on the Cassini spacecraft has measured energetic electrons in the energy range 20-300 keV within Saturn's magnetosphere. In the outer magnetosphere, beyond ∼20 RS, these electrons and their spectral index display strong variations…
Beam-plasma interaction in randomly inhomogeneous plasmas and statistical properties of small-amplitude Langmuir waves in the solar wind and electron foreshock
Pickett, J. S.; Soucek, J.; Krasnoselskikh, V. V. +3 more
A numerical model for wave propagation in an unstable plasma with inhomogeneities is developed. This model describes the linear interaction of Langmuir wave packets with an electron beam and takes into account the angular diffusion of the wave vector due to wave scattering on small-amplitude density fluctuations, as well as suppression of the inst…
Cassini/Cosmic Dust Analyzer in situ dust measurements between Jupiter and Saturn
Dikarev, V.; Kempf, S.; Srama, R. +5 more
We report an analysis of the Cosmic Dust Analyzer data obtained during the interplanetary cruise of the Cassini spacecraft between Jupiter and Saturn. The data cover the time period between the Jupiter flyby and the Saturn orbit insertion. Seventeen dust particles on bound and unbound (hyperbolic) orbits were also detected, with sizes in the submi…
Earthward flowing plasmoid: Structure and its related ionospheric signature
Zong, Q. -G.; Daly, P. W.; Baker, D. N. +11 more
An earthward moving plasmoid has been observed on 28 October 2002 by the Cluster spacecraft with simultaneous auroral viewing by the IMAGE satellite. This offers the opportunity to ascertain the optical and the evolutional signatures in the ionosphere of the earthward moving plasmoid. The ionospheric signatures observed in this paper are not subst…
Field distributions and shapes of Langmuir wave packets observed by Ulysses in an interplanetary type III burst source region
Nulsen, A. L.; Cairns, Iver H.; Robinson, P. A.
There is no consensus on the mechanisms producing the intense bursty Langmuir wave packets routinely observed in source regions of interplanetary type III radio bursts. Using data from the Ulysses Fast Envelope Sampler (FES) near 4 AU, new analyses of the distributions of wavefields clearly separate the Langmuir waves into "intense localized struc…
Breakdown of the frozen-in condition in the Earth's magnetotail
RèMe, H.; Owen, C. J.; Dunlop, M. W. +3 more
We investigate in detail the breakdown of the frozen-in condition detected by Cluster at the downstream distance of ∼19 RE in the midnight sector of the magnetotail during a substorm expansion on 22 August 2001. It is found that the breakdown occurred (1) in a low-density environment with moderate to large proton plasma flow and signifi…
Cluster observations of an auroral potential and associated field-aligned current reconfiguration during thinning of the plasma sheet boundary layer
Karlsson, T.; Marklund, G.; Johansson, T. +1 more
Cluster observations are used to illustrate the reconfiguration of an auroral potential structure encountered at the poleward boundary of the central plasma sheet within the Southern Hemisphere premidnight auroral oval. The reconfiguration from a symmetric U shape to an asymmetric S shape takes place between two consecutive crossings by Cluster sp…