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Erupting Filaments with Large Enclosing Flux Tubes as Sources of High-mass Three-part CMEs, and Erupting Filaments in the Absence of Enclosing Flux Tubes as Sources of Low-mass Unstructured CMEs
Hutton, Joe; Morgan, Huw
The 3-part appearance of many coronal mass ejections (CMEs) arising from erupting filaments emerges from a large magnetic flux tube structure, consistent with the form of the erupting filament system. Other CMEs arising from erupting filaments lack a clear 3-part structure and reasons for this have not been researched in detail. This paper aims to…
Multipoint observation of anisotropy and intermittency in solar-wind turbulence
Perri, S.; Carbone, V.; Sorriso-Valvo, L. +1 more
Using high-resolution magnetic-field Cluster observations, we have investigated the magnetic-field anisotropy via the second- and fourth-order structure functions over a wide range of scales reaching below the subproton scale. The magnetic-field increments have been computed from single- and two-spacecraft measurements. The two-satellite technique…
Extragalactic sources in Cosmic Microwave Background maps
Andreani, P.; Bonavera, L.; Clements, D. L. +15 more
We discuss the potential of a next generation space-borne CMB experiment for studies of extragalactic sources with reference to COrE+, a project submitted to ESA in response to the call for a Medium-size mission (M4). We consider three possible options for the telescope size: 1 m, 1.5 m and 2 m (although the last option is probably impractical, gi…
Differences in the fast optical variability of the dwarf nova V1504 Cyg between quiescence and outbursts detected in Kepler data and simulations of the rms-flux relations
Ness, J. -U.; Dobrotka, A.
An optical light curve of SU UMa type dwarf nova V1504 Cyg taken by Kepler was analysed in order to study fast optical variability (flickering). We calculated power density spectra and rms-flux relations for two different stages of activity, i.e. quiescence and regular outbursts. A multicomponent power density spectrum with two break frequencies w…
On the Continuum Radio Spectrum of Cas A: Possible Evidence of Non-Linear Particle Acceleration
Onić, D.; Urošević, D.
The integrated radio spectrum of Cassiopeia A in continuum was analyzed with special emphasis on possible high-frequency spectral curvature. We conclude that the most probable scenario is that Planck’s new data reveal the imprint of nonlinear particle acceleration in the case of this young Galactic supernova remnant.
Kelvin-Helmholtz instability in coronal mass ejecta in the lower corona
Zhelyazkov, I.; Chandra, R.; Zaqarashvili, T. V.
Aims: We modelled an imaged Kelvin-Helmholtz (KH) instability in coronal mass ejections (CME) in the lower corona by investigating conditions under which kink (m = 1) and m = -3 magnetohydrodynamic (MHD) modes in a uniformly twisted flux tube moving along its axis become unstable.
Methods: We employed the dispersion relations of MHD mode…
Quantifying geological processes on Mars-Results of the high resolution stereo camera (HRSC) on Mars express
Mangold, N.; Jaumann, R.; Scholten, F. +35 more
This review summarizes the use of High Resolution Stereo Camera (HRSC) data as an instrumental tool and its application in the analysis of geological processes and landforms on Mars during the last 10 years of operation. High-resolution digital elevations models on a local to regional scale are the unique strength of the HRSC instrument. The analy…
The Energetics of a Global Shock Wave in the Low Solar Corona
Gallagher, Peter T.; Long, David M.; Baker, Deborah +3 more
As the most energetic eruptions in the solar system, coronal mass ejections (CMEs) can produce shock waves at both their front and flanks as they erupt from the Sun into the heliosphere. However, the amount of energy produced in these eruptions, and the proportion of their energy required to produce the waves, is not well characterized. Here we us…
Revisiting the Local Leo Cold Cloud and Revised Constraints on the Local Hot Bubble
Peek, J. E. G.; Kuntz, K. D.; Snowden, S. L. +4 more
The Local Leo Cold Cloud (LLCC, at a distance of 11-24 pc) was studied in its relation to the Local Hot Bubble (LHB) and the result suggested that much of the observed 1/4 keV emission in that direction originates in front of the cloud. This placed a strong constraint on the distribution of X-ray emission within the LHB and called into question th…
Ensemble Modeling of Successive Halo CMEs: A Case Study
Arge, C. N.; Odstrcil, D.; Pizzo, V. +3 more
The Wang-Sheeley-Arge (WSA)-Enlil cone modeling system is used for making routine arrival-time forecasts of Earth-directed halo coronal mass ejections (CMEs), since they typically produce the most geoeffective events. A major objective of this work is to better understand the sensitivity of the WSA-Enlil modeling results to input model parameters …