E-Print Archive

There are 2659 abstracts currently viewable.
There is a problem with some abstracts that became corrupted following database issues. These will be restored as soon as possible.


Search:

Advanced Search
Options
Main Page Add New E-Print Submitter
Information
Feedback
News Help/FAQ About Preferences
Manage Key Phrase
Notification
Subject will be restored when possible View all abstracts by submitter

Jaroslav Dudik   Submitted: 2008-01-08 03:49

We study the topology of the 3D magnetic field in a filament channel to address the following questions: Is a filament always formed in a single flux tube? How does the photospheric magnetic field lead to filament interruptions and to feet formation? What is the relation between feet-related field lines and the parasitic polarities? What can topological analyzes teach us about EUV filament channels? To do so, we consider a filament observed on October 6th, 2004 with THEMIS/MTR, in Halpha with the full line profile simulatenously and cospatially with its photospheric vector magnetic field. The coronal magnetic field was calculated from a `linear magneto-hydrostatic' extrapolation of a composite THEMIS-MDI magnetogram. Its free parameters were adujsted to get the best match possible between the distribution of modeled plasma-supporting dips and the Halpha filament morphology. The model results in moderate plasma beta < 1 at low altitudes in the filament, in conjunction with non-negligible departures from force-freeness measured by various metrics. The filament here is formed by a splitted flux tube. One part of the flux tube is rooted in the photosphere aside an observed interruption in the filament. This splitted topology is due to strong network polarities on the edge of the filament channel, not to flux concentrations closer to the filament. We focus our study to the North-West portion of the filament. The related flux tube is highly fragmented at low altitudes. This fragmentation is due to small flux concentrations of two types. First, some locally distort the tube, leading to noticeable thickness variations along the filament body. Second, parasitic polarities, associated with filament feet, result in secondary dips above the related local inversion line. These dips belong to long field lines which pass below the flux tube. Many of these field lines are not rooted nearby the related foot. Finally, the present model shows that the coronal void interpretation cannot be ruled out to interprete the wideness of EUV filament channels.

Authors: Dudik, J., Aulanier, G., Schmieder, B., Bommier, V., Roudier, T.
Projects: Dutch Open Telescope,SoHO-MDI,TRACE

Publication Status: SoPh (accepted)
Last Modified: 2008-01-08 07:37
Go to main E-Print page  Subject will be restored when possible  Subject will be restored when possible  Edit Entry  Download Preprint  Delete Entry 

Key
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
Solar-cycle related variation of solar differential rotation
Internal-cycle variation of solar differential rotation
The standard flare model in three dimensions III. Slip-running reconnection properties
Global axis shape of magnetic clouds deduced from the distribution of their local axis orientation
Fine-scale Structures of Flux Ropes Tracked by Erupting Material
The influence of numerical resolution on coronal density in hydrodynamic models of impulsive heating
Spectral diagnostics with the SDO EVE flare lines
A revised radiometric calibration for the Hinode/EIS instrument
Disturbances in the U.S. electric grid associated with geomagnetic activity
Origin of Macrospicule and Jet in Polar Corona by A Small-scale Kinked Flux-Tube
Spatially Resolved Microwave Observations of Multiple Periodicities in a Flaring Loop
Changes in quasi-periodic variations of solar photospheric fields: precursor to the deep solar minimum in the cycle 23?
Pathways of large-scale magnetic couplings between coronal events
Superflares on Solar-Type Stars Observed with Kepler II. Photometric Variability of Superflare-Generating Stars : A Signature of Stellar Rotation and Starspots
A Challenging Solar Eruptive Event of 18 November 2003 and the Causes of the 20 November Geomagnetic Superstorm. I. Unusual History of an Eruptive Filament
Hi-C & AIA observations of transverse MHD waves in active regions
Geometric properties of acoustic waves generated by a point source in the solar-like interior: effects of acoustic cutoff frequency
Study of Failed CME Core Associated with Asymmetric Filament Eruption
Simulation of the Observed Coronal Kink Instability and Its Implications for the SDO/AIA
Investigating Two Successive Flux Rope Eruptions In A Solar Active Region

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



© 2003 Solar Physics Group - Montana State University