Search Publications
CME flux rope and shock identifications and locations: Comparison of white light data, Graduated Cylindrical Shell model, and MHD simulations
St. Cyr, O. C.; Gopalswamy, N.; Cairns, Iver H. +2 more
Coronal mass ejections (CMEs) are major transient phenomena in the solar corona that are observed with ground-based and spacecraft-based coronagraphs in white light or with in situ measurements by spacecraft. CMEs transport mass and momentum and often drive shocks. In order to derive the CME and shock trajectories with high precision, we apply the…
An empirical model of ion plasma in the inner magnetosphere derived from CRRES/MICS measurements
Fennell, J. F.; Claudepierre, S. G.; Chen, M. W. +1 more
We describe an empirical model of energetic ion plasma (∼20-400 keV/q) that is constructed from measurements taken by the Magnetospheric Ion Composition Spectrometer (MICS) instrument that flew on the CRRES spacecraft. This is a unique data set in that it provides energetic ion composition in the near-equatorial ring current region during a very a…
Oxygen ion response to proton bursty bulk flows
Karlsson, Tomas; Nilsson, Hans; Gunell, Herbert +6 more
We have used Cluster spacecraft data from the years 2001 to 2005 to study how oxygen ions respond to bursty bulk flows (BBFs) as identified from proton data. We here define bursty bulk flows as periods of proton perpendicular velocities more than 100 km/s and a peak perpendicular velocity in the structure of more than 200 km/s, observed in a regio…
Reconnection layer bounded by switch-off shocks: Dayside magnetopause crossing by THEMIS D
Phan, Tai; Eriksson, Stefan; Haaland, Stein +2 more
We discuss observations of reconnection, obtained by Time History of Events and Macroscale Interactions during Substorms (THEMIS) D during an outward bound traversal of the low-latitude dayside magnetopause. The reconnection signatures include high magnetic shear, a southward directed Alfvénic jet, bounded by slow-mode shocks near the switch-off l…
Substructures within a dipolarization front revealed by high-temporal resolution Cluster observations
Fazakerley, A. N.; Owen, C. J.; Guo, R. L. +8 more
The dipolarization front (DF), usually observed near the leading edge of a bursty bulk flow (BBF), is thought to carry an intense current sufficient to modify the large-scale near-Earth magnetotail current system. However, the physical mechanism of the current generation associated with DFs is poorly understood. This is primarily due to the limita…
Characteristics of field-aligned currents associated with magnetic flux ropes in the magnetotail: A statistical study
Zhao, Yan; Wang, Rongsheng; Du, Aimin
We present an investigation of 35 magnetic flux ropes encountered by Cluster in the Earth's magnetotail during the years between 2001 and 2004. The study shows that the parallel current dominates inside 86% of the identified flux ropes and 71% of the flux ropes are surrounded by the draping regions where the parallel current is comparable to the p…
Photochemistry of forbidden oxygen lines in the inner coma of 67P/Churyumov-Gerasimenko
Gunell, H.; Altwegg, K.; Fuselier, S. A. +19 more
Observations of the green and red-doublet emission lines have previously been realized for several comets. We present here a chemistry-emission coupled model to study the production and loss mechanisms of the O(1S) and O(1D) states, which are responsible for the emission lines of interest for comet 67P/Churyumov-Gerasimenko. …
Comparative aeronomy: Molecular ionospheres at Earth and Mars
Withers, Paul; Moore, Luke; Vogt, Marissa F. +6 more
The ionospheres in our solar system vary not only in their electron densities but also in the dominance of atomic versus molecular ions at their altitudes of peak plasma density. With the exception of Earth's F layer composed of atomic oxygen ions and electrons, all other planets have their peak ionospheric layers composed of molecular ions and el…
Fine-pitch CdTe detector for hard X-ray imaging and spectroscopy of the Sun with the FOXSI rocket experiment
Takahashi, Tadayuki; Saito, Shinya; Watanabe, Shin +8 more
We have developed a fine-pitch hard X-ray (HXR) detector using a cadmium telluride (CdTe) semiconductor for imaging and spectroscopy for the second launch of the Focusing Optics Solar X-ray Imager (FOXSI). FOXSI is a rocket experiment to perform high sensitivity HXR observations from 4 to 15 keV using the new technique of HXR focusing optics. The …
Emission of hydrogen energetic neutral atoms from the Martian subsolar magnetosheath
Kallio, E.; Barabash, S.; Futaana, Y. +3 more
We have simulated the hydrogen energetic neutral atom (ENA) emissions from the subsolar magnetosheath of Mars using a hybrid model of the proton plasma charge exchanging with the Martian exosphere to study statistical features revealed from the observations of the Neutral Particle Detectors on Mars Express. The simulations reproduce well the obser…