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How To Use Magnetic Field Information For Coronal Loop Identification
Solanki, S. K.; Inhester, B.; Lagg, A. +1 more
The structure of the solar corona is dominated by the magnetic field because the magnetic pressure is about four orders of magnitude higher than the plasma pressure. Due to the high conductivity the emitting coronal plasma (visible, e.g., in SOHO/EIT) outlines the magnetic field lines. The gradient of the emitting plasma structures is significantl…
Multi-Wavelength Analysis of High-Energy Electrons in Solar Flares: A Case Study of the August 20, 2002 Flare
Kontar, Eduard P.; Kašparová, Jana; Dennis, Brian R. +2 more
A multi-wavelength spatial and temporal analysis of solar high-energy electrons is conducted using the August 20, 2002 flare of an unusually flat (γ1 = 1.8) hard X-ray spectrum. The flare is studied using RHESSI, Hα, radio, TRACE, and MDI observations with advanced methods and techniques never previously applied in the solar flare conte…
Rotational Tomography For 3d Reconstruction Of The White-Light And Euv Corona In The Post-Soho Era
Frazin, Richard A.; Kamalabadi, Farzad
Improving our understanding of the mechanisms that energize the solar wind and heat structures in the solar corona requires the development of empirical methods that can determine the three-dimensional (3D) temperature and density distributions with as much spatial and temporal resolution as possible. This paper reviews the solar rotational tomogr…
2D Feature Recognition And 3d Reconstruction In Solar Euv Images
Aschwanden, Markus J.
EUV images show the solar corona in a typical temperature range of T >rsim 1 MK, which encompasses the most common coronal structures: loops, filaments, and other magnetic structures in active regions, the quiet Sun, and coronal holes. Quantitative analysis increasingly demands automated 2D feature recognition and 3D reconstruction, in order to…
The Interplanetary Responses to the Great Solar Activities in Late October 2003
Wang, Yuming; Wang, Jingxiu; Wang, S. +4 more
Based on the observations of the Sun and the interplanetary medium, a series of solar activities in late October 2003 and their consequences are studied comprehensively. Thirteen X-ray flares with importance greater than M-class, six frontside halo coronal mass ejections (CMEs) with span angle larger than 100∘ and three associated erupt…
On Three-Dimensional Magnetic Skeleton Elements Due to Discrete Flux Sources
Longcope, D. W.; Beveridge, C.
The magnetic field in the solar corona plays an important role in coronal heating, flaring activity and many other phenomena studied on the Sun. Magnetic topology is frequently used to understand complicated coronal magnetic fields. By calculating the skeleton of a field, it is possible to build up a sophisticated representation of the key element…
Diffuse Component Spectra of Solar Active Regions at Submillimeter Wavelengths
Silva, Adriana V. R.; Kaufmann, Pierre; Levato, Hugo +4 more
Solar maps at 212 and 405 GHz obtained by the Solar Submillimetric Telescope (SST) show regions of enhanced brightness temperature, which coincide with the location of active regions. A statistical study of the radio emission from these active regions was performed for the first time at such high frequencies during 23 days on June and July 2002, w…
Relating White-Light Coronal Images to Magnetic Fields and Plasma Flow
Woo, Richard
The solar magnetic field is key to a detailed understanding of the Sun's atmosphere and its transition to the solar wind. However, the lack of detailed magnetic field measurements everywhere except at the photosphere has made it challenging to determine its topology and to understand how it produces the observed plasma properties of the corona and…
On the Fractal Structure of Solar Supergranulation
Singh, Jagdev; Paniveni, U.; Krishan, V. +1 more
We employ fractal analysis to study the complexity of supergranulation structure using the Solar and Heliospheric Observatory (SOHO) dopplergrams. Our data consists of 200 visually selected supergranular cells, for which we find a broad, slightly asymmetric dispersion in the size distribution, with the most probable size around 31.9 Mm. From the a…
Very Large Array and SOHO Observations of Type I Noise Storms, Large-Scale Loops and Magnetic Restructuring in the Corona
Willson, Robert F.
Very Large Array (VLA) observations at 91-cm wavelength are combined with data from the SOHO EIT, MDI and LASCO and used to study the evolving coronal magnetic environment in which Type I noise storms and large-scale coronal loops occur. On one day, we have shown the early evolution of a coronal mass ejection (CME) in projection in the disk by tra…