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Longitudinal Waves in Coronal Loops
de Moortel, I.
Outwardly propagating intensity disturbances are a common feature in large, quiescent coronal loop structures. In this paper, an overview is given of the observed properties and the theoretical modelling. As a large number of events have been observed and analysed, good statistical results on the estimated parameters have now been obtained. The th…
Alfvén Waves and Their Roles in the Dynamics of the Earth's Magnetotail: A Review
Keiling, Andreas
The Earth’s magnetotail is an extremely complex system which—energized by the solar wind—displays many phenomena, and Alfvén waves are essential to its dynamics. While Alfvén waves were first predicted in the early 1940’s and ample observations were later made with rockets and low-altitude satellites, observational evidence of Alfvén waves in diff…
Solar Surface Magnetism and Irradiance on Time Scales from Days to the 11-Year Cycle
Solanki, S. K.; Schmutz, W.; Haberreiter, M. +9 more
The uninterrupted measurement of the total solar irradiance during the last three solar cycles and an increasing amount of solar spectral irradiance measurements as well as solar imaging observations (magnetograms and photometric data) have stimulated the development of models attributing irradiance variations to solar surface magnetism. Here we r…
Plasmaspheric Density Structures and Dynamics: Properties Observed by the CLUSTER and IMAGE Missions
de Keyser, Johan; Carpenter, Donald L.; Darrouzet, Fabien +11 more
Plasmaspheric density structures have been studied since the discovery of the plasmasphere in the late 1950s. But the advent of the Cluster and Image missions in 2000 has added substantially to our knowledge of density structures, thanks to the new capabilities of those missions: global imaging with Image and four-point in situ measurements with C…
Heating Diagnostics with MHD Waves
Erdélyi, R.; Taroyan, Y.
The heating of the solar atmosphere is a fundamental problem of modern solar and astrophysics. A review of the seismological aspects of magnetohydrodynamic (MHD) waves with an emphasis on standing longitudinal waves in the context of coronal heating is presented. Efforts made recently may be split into two categories: forward modelling and data in…
Neutral H Density at the Termination Shock: A Consolidation of Recent Results
Möbius, E.; Bzowski, M.; Gloeckler, G. +2 more
We discuss a consolidation of determinations of the density of neutral interstellar H at the nose of the termination shock carried out with the use of various data sets, techniques, and modeling approaches. In particular, we focus on the determination of this density based on observations of H pickup ions on Ulysses during its aphelion passage thr…
Recent Progress in Physics-Based Models of the Plasmasphere
André, Nicolas; Jordanova, Vania K.; Lemaire, Joseph F. +5 more
We describe recent progress in physics-based models of the plasmasphere using the fluid and the kinetic approaches. Global modeling of the dynamics and influence of the plasmasphere is presented. Results from global plasmasphere simulations are used to understand and quantify (i) the electric potential pattern and evolution during geomagnetic stor…
Electric Fields and Plasma Processes in the Auroral Downward Current Region, Below, Within, and Above the Acceleration Region
Marklund, G. T.
The downward field-aligned current region plays an active role in magnetosphere-ionosphere coupling processes associated with aurora. A quasi-static electric field structure with a downward parallel electric field forms at altitudes between 800 km and 5000 km, accelerating ionospheric electrons upward, away from the auroral ionosphere. A wealth of…
Augmented Empirical Models of Plasmaspheric Density and Electric Field Using IMAGE and CLUSTER Data
Gallagher, Dennis L.; Tu, Jiannan; Moldwin, Mark B. +4 more
Empirical models for the plasma densities in the inner magnetosphere, including plasmasphere and polar magnetosphere, have been in the past derived from in situ measurements. Such empirical models, however, are still in their initial phase compared to magnetospheric magnetic field models. Recent studies using data from CRRES, Polar, and Image have…
The Topology and Behavior of Magnetic Fields Emerging at the Solar Photosphere
Lites, B. W.
The nature of flux emerging through the surface layers of the Sun is examined in the light of new high-resolution magnetic field observations from the Hinode space mission. The combination of vector magnetic field data and visible-light imaging from Hinode support the hypothesis that active region filaments are created as a result of an emerging, …