Search Publications
Modeling anomalous cosmic ray oxygen gradients over successive solar cycles
Potgieter, M. S.; Strauss, R. D.
Cosmic ray drift directions depend both on the charge of the particle population under consideration, as well as the heliospheric magnetic field polarity which oscillates within a ∼22 year cycle. The differences in the cosmic ray drift patterns between successive solar cycles manifest themselves in the sign of the latitudinal cosmic ray gradient. …
Auroral kilometric radiation diurnal, semidiurnal, and shorter-term modulations disentangled by Cassini
Cecconi, B.; Lamy, L.; Zarka, P. +1 more
During the flyby of the Earth by Cassini in 1999, the Radio and Plasma Wave Science (RPWS) instrument recorded a month of quasi-continuous observations of auroral kilometric radiation (AKR). Analyzing the full polarization of incoming radio waves, we found AKR to be 100% circular left-handed (LH) or right-handed (RH). As AKR is emitted predominant…
Multiple harmonic ULF waves in the plasma sheet boundary layer observed by Cluster
RèMe, H.; Owen, C. J.; Keiling, A. +7 more
The passage of the Cluster satellites in a polar orbit through Earth's magnetotail has provided numerous observations of harmonically related Pc 1-2 ULF wave events, with the fundamental near the local proton cyclotron frequency Ωcp. Broughton et al. (2008) reported observations by Cluster of three such events in the plasma sheet bounda…
Some statistical properties of flow bursts in the magnetotail
Kim, Hyun-Sook; Lee, Dae-Young; Ohtani, Shin-Ichi +2 more
We investigated the properties of physical parameters during earthward flow burst (FB) events in the near-Earth magnetic tail. For the investigation, we used the measurements made by two of the Cluster satellites, C1 and C4, from 2001 to 2003 and selected FB events based on a set of strict criteria. First, while we confirmed the well-known fact th…
Backscattered solar wind protons by Phobos
Fedorov, A.; Barabash, S.; Lundin, R. +5 more
We report Mars Express (MEX) measurements showing that the regolith-covered Phobos surface backscatters 0.5%-10% of the impinging solar wind protons. Backscattered protons with an energy corresponding to 30%-40% of the solar wind energy injected in the flow are picked up by the solar wind and may cause field disturbances and wave activity. Since a…
Surface charging of Saturn's plasma-absorbing moons
Krupp, N.; Jones, G. H.; Roussos, E. +1 more
Recent results from the study of the interaction of Earth's moon with the solar wind have highlighted lunar surface charging as an important physical process not only for the local interaction of the surface and the impinging plasma but also for charged dust ejection and transport. Excluding Earth's moon, however, such studies have been limited to…
Properties of the thermal ion plasma near Rhea as measured by the Cassini plasma spectrometer
Persoon, A. M.; Wilson, R. J.; Tokar, R. L. +1 more
Rhea is the second largest Saturnian satellite orbiting at 8.74 Saturn radii within the magnetosphere's near corotating thermal plasma. Rhea's orbital speed is less than the corotation speed, so the thermal plasma forms a wake in the direction of Rhea's orbital motion. During 26 November 2005, Cassini passed within 500 km of Rhea and through this …
Inductive electric fields in the inner magnetosphere during geomagnetically active periods
Mende, S. B.; Zheng, Y.; Brandt, P. C. +3 more
The present study examines the characteristics of electric fields in the nightside inner magnetosphere during geomagnetically active periods. Electric field and magnetic field measurements made by the Cluster spacecraft on their perigee passes are used. The results are summarized as follows: (1) The duskward electric field component EY …
Interaction of Saturn's magnetosphere and its moons: 2. Shape of the Enceladus plume
Russell, C. T.; Khurana, K. K.; Gombosi, T. I. +3 more
The Saturnian moons in the inner magnetosphere are immersed in a plasma disk that rotates much faster than the moon's Keplerian speed. The interaction of the rotating plasma with the moons results in a disturbance in the Saturnian magnetospheric plasma that depends on the nature of obstacle that the moon represents. In particular at Enceladus, suc…
Energetic neutral atoms from Titan: Particle simulations in draped magnetic and electric fields
Saur, Joachim; Simon, Sven; Strobel, Darrell F. +2 more
Titan's atmosphere emits energetic neutral atoms (ENAs), which are being monitored for the first time by the Cassini spacecraft. These ENAs are generated by charge exchange processes of energetic ions with neutrals from Titan's atmosphere. In this work we investigate the morphology of the ENA emission from Titan's atmosphere with a three-dimension…