Search Publications
Fast coronal mass ejection environments and the production of solar energetic particle events
Vourlidas, A.; Kahler, S. W.
The search continues for coronal environmental factors that determine whether a fast coronal mass ejection (CME) results in a solar energetic particle (SEP) event at 1 AU. From a plot of peak 20 MeV SEP intensities versus associated CME speeds we select for comparison two groups of fast, wide, western hemisphere CMEs observed with the LASCO corona…
Quasi-monochromatic ULF foreshock waves as observed by the four-spacecraft Cluster mission: 1. Statistical properties
Balogh, A.; Dandouras, I.; Eastwood, J. P. +2 more
Cluster data are used to study the statistics of a particular type of foreshock wave: quasi-monochromatic ultra-low-frequency (ULF) waves with characteristic periods of 30 s in the spacecraft frame. On the basis of a large set of foreshock observations made in 2001 with spacecraft separations ∼600 km, the intrinsic properties of the waves are foun…
How good is the relationship of solar and interplanetary plasma parameters with geomagnetic storms?
Kane, R. P.
Since the work of Snyder et al. (1963), who showed a possible link between interplanetary solar wind speed V and geomagnetic index Kp, such a relationship has been examined by many workers and found to be rather loose. In the present communication this relationship is rechecked for all data during 1973-2003. It was noted that moderate or strong ge…
Forecast evaluation of the coronal mass ejection (CME) geoeffectiveness using halo CMEs from 1997 to 2003
Cho, K. -S.; Kim, Y. -H.; Moon, Y. -J. +5 more
In this study we have made a forecast evaluation of geoeffective coronal mass ejections (CMEs) by using frontside halo CMEs and the magnetospheric ring current index, Dst. This is the first time, to our knowledge, that an attempt has been made to construct contingency tables depending on the geoeffectiveness criteria as well as to estimate the pro…
Initial results of high-latitude magnetopause and low-latitude flank flux transfer events from 3 years of Cluster observations
Russell, C. T.; Zhang, H.; Zong, Q. -G. +9 more
We present initial results from a statistical study of Cluster multispacecraft flux transfer event (FTE) observations at the high-latitude magnetopause and low-latitude flanks from February 2001 to June 2003. Cluster FTEs are observed at both the high-latitude magnetopause and low-latitude flanks for both southward and northward IMF. Among the 122…
Signature of Saturn's auroral cusp: Simultaneous Hubble Space Telescope FUV observations and upstream solar wind monitoring
Cowley, Stanley W. H.; Bunce, Emma J.; Clarke, John T. +3 more
Model simulations by Bunce et al. (2005a) have shown that direct precipitation of electrons in Saturn's dayside cusp regions is not capable of producing significant FUV aurora. Instead, they suggested the possibility that the FUV bright emissions sometimes observed near noon are associated with reconnection occurring at the dayside magnetopause, p…
Reconnection sites of spatial cusp structures
Yeoman, T. K.; Fuselier, S. A.; Reme, H. +4 more
The interconnection of the interplanetary magnetic field with the geomagnetic field is thought to be the dominant process for mass, energy, and momentum transfer from the magnetosheath into the magnetosphere. Downward precipitating ions from the reconnection site are observed in the cusp by polar orbiting satellites and exhibit sudden changes in t…
Dispersion analysis of low-frequency waves through the terrestrial bow shock
Glassmeier, K. -H.; Narita, Y.
We present dispersion relations of low-frequency waves observed upstream and downstream of the Earth's bow shock analyzing Cluster magnetometer measurements along an outbound orbit covering four regions: the foreshock, the outer, the middle, and the inner magnetosheath. The aim of our study is to better understand wave transmission, mode conversio…
Nonlinear Alfvén, magnetosonic, sound, and electron inertial waves in fluid formalism
Stasiewicz, K.
A fluid model of nonlinear electron and ion inertial waves in anisotropic plasmas is presented. The model has been verified for plasma beta (ratio of kinetic/magnetic pressures) in a range between 0.1 and 15. It is shown that warm plasmas support four types of nonlinear waves, which correspond to four linear modes, Alfvénic, magnetosonic, sound, a…
Ion distributions in Saturn's magnetosphere near Titan
Cravens, T. E.; Ledvina, S. A.; KecskeméTy, K.
Titan's interaction with Saturn's magnetosphere is studied using a combination of a three-dimensional (3-D) single-fluid magnetohydrodynamic (MHD) simulation and a test particle/Monte Carlo model. The MHD simulation includes an exosphere model based on the one used in the work of Cravens et al. (1998), simple ionospheric processes such as ion prod…