Search Publications
Flow of mass and energy in the magnetospheres of Jupiter and Saturn
Delamere, Peter A.; Bagenal, Fran
We present simple models of the plasma disks surrounding Jupiter and Saturn based on published measurements of plasma properties. We calculate radial profiles of the distribution of plasma mass, pressure, thermal energy density, kinetic energy density, and energy density of the suprathermal ion populations. We estimate the mass outflow rate as wel…
Bursty bulk flows and dipolarization in MHD simulations of magnetotail reconnection
Nakamura, R.; Hesse, M.; Birn, J. +1 more
Using three-dimensional MHD simulations of magnetic reconnection in the magnetotail, we investigate the fate of earthward bursty bulk flows (BBFs). The flow bursts are identified as entropy-depleted magnetic flux tubes (“bubbles”) generated by the severance of a plasmoid via magnetic reconnection. The onset of fast reconnection coincides closely w…
Causes of low thermospheric density during the 2007-2009 solar minimum
Woods, Thomas N.; Didkovsky, Leonid V.; Solomon, Stanley C. +2 more
Satellite drag data indicate that the thermosphere was lower in density, and therefore cooler, during the protracted solar minimum period of 2007-2009 than at any other time in the past 47 years. Measurements indicate that solar EUV irradiance was also lower than during the previous solar minimum. However, secular change due to increasing levels o…
Triggering process of whistler mode chorus emissions in the magnetosphere
Omura, Yoshiharu; Nunn, David
Chorus emissions are triggered from the linear cyclotron instability driven by the temperature anisotropy of energetic electrons (10-100 keV) in the magnetosphere. Chorus emissions grow as an absolute nonlinear instability near the magnetic equator because of the presence of an electromagnetic electron hole in velocity space. The transition proces…
Does the F10.7 index correctly describe solar EUV flux during the deep solar minimum of 2007-2009?
Liu, Libo; Wan, Weixing; Chen, Yiding
This paper shows that the relationship between solar EUV flux and the F10.7 index during the extended solar minimum (Smin) of 2007-2009 is different from that in the previous Smin. This difference is also seen in the relationship between foF2 and F10.7. We collected SOHO/SEM EUV observations and the F
Dusty plasma in the vicinity of Enceladus
Gurnett, D. A.; Persoon, A. M.; Kurth, W. S. +7 more
We present in situ Cassini Radio Plasma Wave Science observations in the vicinity of Enceladus and in the E ring of Saturn that indicate the presence of dusty plasma. The four flybys of Enceladus in 2008 revealed the following cold plasma characteristics: (1) there is a large plasma density (both ions and electrons) within the Enceladus plume regi…
Model of the Jovian magnetic field topology constrained by the Io auroral emissions
Bonfond, B.; Zarka, P.; Grodent, D. +1 more
The determination of the internal magnetic field of Jupiter has been the object of many studies and publications. These models have been computed from the Pioneer, Voyager, and Ulysses measurements. Some models also use the position of the Io footprints as a constraint: the magnetic field lines mapping to the footprints must have their origins alo…
Transport of solar wind fluctuations: A two-component model
Matthaeus, W. H.; Smith, C. W.; Oughton, S. +2 more
We present a new model for the transport of solar wind fluctuations which treats them as two interacting incompressible components: quasi-two-dimensional turbulence and a wave-like piece. Quantities solved for include the energy, cross helicity, and characteristic transverse length scale of each component, plus the proton temperature. The developm…
Excitation of magnetosonic waves in the terrestrial magnetosphere: Particle-in-cell simulations
Gary, S. Peter; Liu, Kaijun; Winske, Dan
Two-dimensional electromagnetic particle-in-cell simulations are performed to study the temporal development of an ion Bernstein instability driven by a proton velocity distribution with positive slope in the perpendicular velocity distribution fp(v$\perp$), where $\perp$ denotes directions perpendicular to the background mag…
Statistical study of coronal mass ejection source locations: Understanding CMEs viewed in coronagraphs
Wang, Yuming; Shen, Chenglong; Wang, S. +3 more
How to properly understand coronal mass ejections (CMEs) viewed in white light coronagraphs is crucial to many relative researches in solar and space physics. The issue is now particularly addressed in this paper through studying the source locations of all the 1078 Large Angle and Spectrometric Coronagraph (LASCO) CMEs listed in Coordinated Data …