Search Publications

Impact of the rippling of a perpendicular shock front on ion dynamics
DOI: 10.1029/2011JA017211 Bibcode: 2012JGRA..117.7222Y

Lembège, B.; Lu, Q. M.; Yang, Z. W.

Both hybrid/full particle simulations and recent experimental results have clearly evidenced that the front of a supercritical quasi-perpendicular shock can be rippled. Recent two-dimensional simulations have focused on two different types of shock front rippling: (1) one characterized by a small spatial scale along the front is supported by lower…

2012 Journal of Geophysical Research (Space Physics)
Cluster 34
A statistical comparison of solar wind propagation delays derived from multispacecraft techniques
DOI: 10.1029/2011JA016946 Bibcode: 2012JGRA..117.2101C

Wild, J. A.; Case, N. A.

We present a large-scale statistical study of the solar wind propagation delay between NASA's Advanced Composition Explorer spacecraft and ESA's Cluster 1 spacecraft. This study focuses on those periods when Cluster was within the unimpeded solar wind, upstream of the bow shock nose, between 2001 and 2010. Using a cross-correlation method to compa…

2012 Journal of Geophysical Research (Space Physics)
Cluster 32
Spatial gradients from irregular, multiple-point spacecraft configurations
DOI: 10.1029/2012JA018075 Bibcode: 2012JGRA..11711207S

Dunlop, M. W.; Rème, H.; Liu, Z. X. +8 more

We present a generalized multipoint analysis of physical quantities, such as magnetic field and plasma flow, based on spatial gradient properties, where the multipoint data may be taken by irregular (distorted) configurations of any number of spacecraft. The methodology is modified from a previous, fully 3-D gradient analysis technique, designed t…

2012 Journal of Geophysical Research (Space Physics)
Cluster 31
Transport of thermal-energy ionospheric oxygen (O+) ions between the ionosphere and the plasma sheet and ring current at quiet times preceding magnetic storms
DOI: 10.1029/2012JA017803 Bibcode: 2012JGRA..117.7215Y

Peterson, W. K.; Yau, Andrew W.; Abe, Takumi +1 more

The presence of energetic O+ ions in the ring current at the onset of a magnetic storm prompts the question of the possible role of “in-transit” ionospheric O+ ions between the ionosphere and the plasma sheet and ring current in the quiet periods immediately preceding the main phase of a magnetic storm. Thermal-energy O+…

2012 Journal of Geophysical Research (Space Physics)
Cassini 31
Nonlinear interaction between ring current protons and electromagnetic ion cyclotron waves
DOI: 10.1029/2012JA018088 Bibcode: 2012JGRA..11712217Z

Zhu, Hui; Su, Zhenpeng; Xiao, Fuliang +4 more

Electromagnetic ion cyclotron (EMIC) waves have long been suggested to account for the rapid decay of ring current, which is usually described by the quasi-linear theory. We demonstrate that the interactions between ring current protons and typical EMIC waves can be highly nonlinear. A dimensionless parameterRis derived to identify the nonlinear i…

2012 Journal of Geophysical Research (Space Physics)
Cluster 30
Inflow direction of interstellar neutrals deduced from pickup ion measurements at 1 AU
DOI: 10.1029/2012JA017746 Bibcode: 2012JGRA..117.9106D

Galvin, Antoinette B.; Wimmer-Schweingruber, Robert F.; Bochsler, Peter +4 more

Observations of interstellar pickup ions inside the heliosphere provide an indirect method to access information on the surrounding interstellar medium. The so-called pickup ion focusing cone and pickup ion crescent, which show an imprint of the related longitudinal distribution of interstellar neutrals in form of two overabundances on the down- a…

2012 Journal of Geophysical Research (Space Physics)
Ulysses 29
Rotational modulation and local time dependence of Saturn's infrared H3+ auroral intensity
DOI: 10.1029/2012JA017990 Bibcode: 2012JGRA..117.9228B

Brown, R. H.; Baines, K. H.; Lamy, L. +10 more

Planetary auroral emissions reveal the configuration of magnetospheric field-aligned current systems. In this study, Cassini Visual and Infrared Mapping Spectrometer (VIMS) observations of Saturn's pre-equinox infrared H3+ aurorae were analysed to show (a) rotational modulation of the auroral intensity in both hemispheres and…

2012 Journal of Geophysical Research (Space Physics)
Cassini 26
Seasonal variations in Saturn's plasma between the main rings and Enceladus
DOI: 10.1029/2011JA017332 Bibcode: 2012JGRA..117.3207E

Wilson, R. J.; Johnson, R. E.; Elrod, M. K. +1 more

With the discovery by the Cassini spacecraft of an oxygen atmosphere over Saturn's main rings, and a strong source of water products from the plumes of Saturn's moon Enceladus, our picture of the physics of Saturn's magnetosphere from the main rings to inside the orbit of Enceladus has changed dramatically. This region contains oxygen ions from th…

2012 Journal of Geophysical Research (Space Physics)
Cassini 26
Precipitation of highly energetic protons by helium branch electromagnetic ion cyclotron triggered emissions
DOI: 10.1029/2012JA017933 Bibcode: 2012JGRA..11712210S

Omura, Yoshiharu; Shoji, Masafumi

In the equatorial region of the Earth's inner magnetosphere, the electromagnetic ion cyclotron (EMIC) triggered emissions are generated through interaction with energetic protons. We investigate the generation process of the EMIC triggered emissions in the He+branch and associated precipitation of the energetic protons using a one-dimen…

2012 Journal of Geophysical Research (Space Physics)
Cluster 26
Thin current sheets in the presence of a guiding magnetic field in Earth's magnetosphere
DOI: 10.1029/2011JA017359 Bibcode: 2012JGRA..117.4212M

Malova, H. V.; Delcourt, D. C.; Petrukovich, A. A. +7 more

A self-consistent theory of relatively thin anisotropic current sheets (TCS) in collisionless plasma is developed, taking into account the presence of a guiding field By (all notations are used in the GSM coordinate system). TCS configurations with a finite value of guiding field By are often observed in Earth's magnetotail a…

2012 Journal of Geophysical Research (Space Physics)
Cluster 25