Search Publications
Correlation and Taylor scale variability in the interplanetary magnetic field fluctuations as a function of solar wind speed
Dasso, S.; Matthaeus, W. H.; Weygand, James M. +1 more
Simultaneous multiple point measurements of the magnetic field from 11 spacecraft are employed to determine the correlation scale and the magnetic Taylor microscale of the solar wind as functions of the mean magnetic field direction and solar wind speed. We find that the Taylor scale is independent of direction relative to the mean magnetic field …
Amplitude dependence of frequency sweep rates of whistler mode chorus emissions
Katoh, Yuto; Omura, Yoshiharu
The frequency and amplitude characteristics of chorus emissions are studied by performing electron hybrid code simulations with different initial number densities of energetic electrons. Chorus emissions with rising tones are generated in all simulation runs except for the simulation assuming the lowest number density. The frequency sweep rates of…
Influence of negatively charged plume grains on the structure of Enceladus' Alfvén wings: Hybrid simulations versus Cassini Magnetometer data
Dougherty, Michele K.; Saur, Joachim; Kriegel, Hendrik +5 more
We apply the hybrid simulation code AIKEF (adaptive ion kinetic electron fluid) to the interaction between Enceladus' plume and Saturn's magnetospheric plasma. For the first time, the influence of the electron-absorbing dust grains in the plume on the plasma structures and magnetic field perturbation, the Alfvén wing, is taken into account within …
How is open solar magnetic flux lost over the solar cycle?
Owens, M. J.; Crooker, N. U.; Lockwood, M.
The Sun's open magnetic field, magnetic flux dragged out into the heliosphere by the solar wind, varies by approximately a factor of 2 over the solar cycle. We consider the evolution of open solar flux in terms of a source and loss term. Open solar flux creation is likely to proceed at a rate dependent on the rate of photospheric flux emergence, w…
Statistical survey on the magnetic structure in magnetotail current sheets
Petrukovich, A. A.; Zhang, T. L.; Lucek, E. +5 more
On the basis of the multipoint magnetic observations of Cluster in the region 15-19 RE downtail, the magnetic field structure in magnetotail current sheet (CS) center is statistically surveyed. It is found that the By component (in GSM coordinates) is distributed mainly within ∣By∣ < 5nT, while the Bz…
Emission and propagation of Saturn kilometric radiation: Magnetoionic modes, beaming pattern, and polarization state
Schippers, P.; Gurnett, D. A.; Kurth, W. S. +7 more
The Cassini mission crossed the source region of the Saturn kilometric radiation (SKR) on 17 October 2008. On this occasion, the Radio and Plasma Wave Science (RPWS) experiment detected both local and distant radio sources, while plasma parameters were measured in situ by the magnetometer and the Cassini Plasma Spectrometer. A goniopolarimetric in…
Atmospheric erosion of Venus during stormy space weather
Fedorov, A.; Barabash, S.; Futaana, Y. +9 more
We study atmospheric escape from Venus during solar minimum conditions when 147 corotating interaction regions (CIRs) and interplanetary coronal mass ejections (ICMEs) combined impact on the planet. This is the largest study to date of the effects of stormy space weather on Venus and we show for the first time statistically that the atmosphere of …
Energetic particle phase space densities at Saturn: Cassini observations and interpretations
Krupp, N.; Jackman, C. M.; Roussos, E. +4 more
Saturn's magnetosphere has been studied extensively by the Cassini spacecraft during the last 6 years. We present mission-averaged energetic proton and electron measurements obtained by the MIMI/LEMMS instrument onboard Cassini in an energy range from several 10 keV to several 10 MeV separated by equatorial pitch angle. We discuss the resulting ra…
Influence of negatively charged plume grains and hemisphere coupling currents on the structure of Enceladus' Alfvén wings: Analytical modeling of Cassini magnetometer observations
Dougherty, Michele K.; Saur, Joachim; Kriegel, Hendrik +3 more
We present an analytical model of the Alfvén wing system that is generated by the interaction between the plume of Enceladus and the corotating plasma in Saturn's inner magnetosphere. Our primary purpose is to explain the orientation of the magnetic field perturbations detected in Enceladus' Alfvén wings by the Cassini magnetometer (MAG) instrumen…
Proton acceleration in antiparallel collisionless magnetic reconnection: Kinetic mechanisms behind the fluid dynamics
Belmont, G.; Aunai, N.; Smets, R.
This paper investigates the proton kinetic mechanisms leading to the formation of plasma jets in antiparallel magnetic reconnection. In particular, the interaction of the protons with the Hall electric field in the proton non-ideal region is discussed. The study, based on a two-dimensional hybrid simulation, details the important role of the proto…