Search Publications
A statistical study of magnetospheric ion composition along the geomagnetic field using the Cluster spacecraft for L values between 5.9 and 9.5
Dandouras, I.; Sandhu, J. K.; Yeoman, T. K. +1 more
Using ion density data obtained by the CODIF (ion Composition and Distribution Function analyser) instrument on board the Cluster spacecraft, for the interval spanning 2001-2005, an empirical model describing the average ion mass distribution along closed geomagnetic field lines is determined. The empirical model describes the region spanning 5.9≤…
Modulation of the substorm current wedge by bursty bulk flows: 8 September 2002—Revisited
Nakamura, R.; Sergeev, V. A.; Milan, S. E. +12 more
The ultimate formation mechanism of the substorm current wedge (SCW) remains to date unclear. In this study, we investigate its relationship to plasma flows at substorm onset and throughout the following expansion phase. We revisit the case of 8 September 2002, which has been defined as "one of the best textbook examples of a substorm" because of …
Statistics of energetic electrons in the magnetotail reconnection
Xu, Xiaojun; Huang, Shiyong; Zhou, Meng +5 more
Magnetic reconnection has long been regarded as an important site for producing energetic electrons in solar terrestrial and astrophysical plasmas. The motivation of this paper is to provide the average properties of energetic electrons in reconnection region, which are crucial for understanding electron energization mechanism but are rarely known…
Coalescence of magnetic flux ropes observed in the tailward high-speed flows
Zhao, Yan; Yao, Zhonghua; Lu, Quanming +3 more
We report a tailward high-speed flow event observed by Cluster during 0203:00UT-0205:30UT on 20 September 2003. Within the flows, a series of three bipolar Bz signatures were observed. The first and third bipolar Bz signatures are identified as magnetic flux ropes, while the middle one is found to result from the collision of…
Source region and growth analysis of narrowband Z-mode emission at Saturn
Gurnett, D. A.; Coates, A. J.; Santolík, O. +5 more
Intense Z-mode emission is observed in the lower density region near the inner edge of the Enceladus torus at Saturn, where these waves may resonate with MeV electrons. The source mechanism of this emission, which is narrow-banded and most intense near 5 kHz, is not well understood. We survey the Cassini Radio and Plasma Wave Science data to isola…
Shadowing and anisotropy of solar energetic ions at Mars measured by MAVEN during the March 2015 solar storm
Lee, Christina O.; Larson, Davin; Halekas, Jasper S. +4 more
The Solar Energetic Particle (SEP) Instrument on the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft is meant to characterize the variability of SEP fluxes at Mars. SEP ion precipitation is an important source of heating, ionization, and chemical changes in the upper atmosphere of Mars and may have played a substantial role in driving at…
Transport of magnetic flux and mass in Saturn's inner magnetosphere
Lai, H. R.; Russell, C. T.; Jia, Y. D. +2 more
It is well accepted that cold plasma sourced by Enceladus is ultimately lost to the solar wind, while the magnetic flux convecting outward with the plasma must return to the inner magnetosphere. However, whether the interchange or reconnection, or a combination of the two processes is the dominant mechanism in returning the magnetic flux is still …
Scientific considerations for future spectroscopic measurements from space of activity on the Sun
Holman, Gordon D.
High-resolution UV and X-ray spectroscopy are important to understanding the origin and evolution of magnetic energy release in the solar atmosphere, as well as the subsequent evolution of heated plasma and accelerated particles. Electromagnetic radiation is observed from plasma heated to temperatures ranging from about 10 kK to above 10 MK, from …
Spaced-based search coil magnetometers
Hospodarsky, George B.
Search coil magnetometers are one of the primary tools used to study the magnetic component of low-frequency electromagnetic waves in space. Their relatively small size, mass, and power consumption, coupled with a good frequency range and sensitivity, make them ideal for spaceflight applications. The basic design of a search coil magnetometer cons…
Energy dependence of SEP electron and proton onset times
St. Cyr, O. C.; Gopalswamy, N.; Mäkelä, P. +1 more
We study the large solar energetic particle (SEP) events that were detected by GOES in the >10 MeV energy channel during December 2006 to March 2014. We derive and compare solar particle release (SPR) times for the 0.25-10.4 MeV electrons and 10-100 MeV protons for the 28 SEP events. In the study, the electron SPR times are derived with the tim…