E-Print Archive

There are 4524 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
The Magnetic Structure of Coronal Loops Observed by TRACE View all abstracts by submitter

Marcelo Lopez-Fuentes   Submitted: 2005-07-28 13:42

Previous studies have found that coronal loops have a nearly uniform thickness, which seems to disagree with the characteristic expansion of active region magnetic fields. This is one of the most intriguing enigmas in solar physics. We here report on the first comprehensive one-to-one comparison of observed loops with corresponding magnetic flux tubes obtained from cotemporal magnetic field extrapolation models. We use EUV images from TRACE, magnetograms from the MDI instrument on SOHO, and linear force-free field extrapolations. For each loop, we find the particular value of the force-free parameter α that best matches the observed loop axis and then construct flux tubes using different assumed cross sections at one footpoint (circle and ellipses with different orientations). We find that the flux tubes expand with height by typically twice as much as the corresponding loops. We also find that many flux tubes are much wider at one footpoint than the other, whereas the corresponding loops are far more symmetric. It is clear that the actual coronal magnetic field is more complex than the models we have considered. We suggest that the observed symmetry of loops is related to the tangling of elemental magnetic flux strands produced by photospheric convection.

Authors: M. C. Lopez Fuentes, J. A. Klimchuk, P. Demoulin

Publication Status: Accepted for publication in ApJ
Last Modified: 2005-11-03 12:56
Go to main E-Print page  Self and Mutual Magnetic Helicities in Coronal Magnetic Configurations  Toward Interplanetary Space Weather: Strategies for Manned Missions to Mars  Edit Entry  Download Preprint  Submitter's Homepage Delete Entry 

Go to main E-Print pageGo to main E-Print page.
Previous AbstractPrevious Abstract.
Next AbstractNext Abstract.
Download PreprintDownload Preprint.
Submitter's HomepageSubmitters Homepage.
Edit EntryEdit Entry.
View All Abstracts By SubmitterView all abstracts by submitter.
Delete AbstractDelete abstract.

Latest Entries
Coronal seismology by slow waves in non-adiabatic conditions
Exploring the Ideal MHD Quasi-Modes of a Plasma Interface with a Thick Nonuniform Transition
Changes of Magnetic Energy and Helicity in Solar Active Regions from Major Flares
Spectroscopic and Imaging Observations of Spatially Extended Magnetic Reconnection in the Splitting of a Solar Filament Structure
The Universality of Power Law Slopes in the Solar Photosphere and Transition Region Observed with HMI and IRIS
Turbulence and Anomalous Resistivity inside Near-Earth Magnetic Clouds
On the specific energy and pressure in near-Earth magnetic clouds
Solar Energetic Particle Event Associated with the 2012 July 23 Extreme Solar Storm
Investigation of Energetic Particle Release Using Multi-point Imaging and In Situ Observations
Shock Properties and Associated Characteristics of Solar Energetic Particles in the 2017 September 10 GLE event
Dimensionality of Solar Magnetic Reconnection
Microwave Perspective on Magnetic Breakout Eruption
Effects of Coronal Density and Magnetic Field Distributions on a Global Solar EUV Wave
Multi-spacecraft Observations of the Coronal and Interplanetary Evolution of a Solar Eruption Associated with Two Active Regions
Sun-to-Earth Characteristics of the 2012 July 12 Coronal Mass Ejection and Associated Geo-effectiveness
The effect of nanoflare flows on EUV spectral lines
On some features of the solar proton event on 2021 October 28 GLE73
The role and contribution of magnetic fields, characterized via their magnetic flux, to the statistical structuring of the solar atmosphere
Do periods of decayless kink oscillations of solar coronal loops depend on noise?
Automatic detection technique for solar filament oscillations in GONG data

Related Pages
MSU Solar Physics.
Max Millennium Science Mail Archive.
Max Millennium Message of the Day Mail Archive.
Max Millennium Flare Catalog

Archive Maintainer
Alisdair Davey

© 2000-2020 Solar Physics Group - Montana State University