Issue |
A&A
Volume 456, Number 2, September III 2006
|
|
---|---|---|
Page(s) | 665 - 673 | |
Section | The Sun | |
DOI | https://doi.org/10.1051/0004-6361:20064865 | |
Published online | 31 August 2006 |
Vector tomography for the coronal magnetic field
I. Longitudinal Zeeman effect measurements
Max-Planck-Institut für Sonnensystemforschung, 37191 Katlenburg-Lindau, Germany e-mail: [kramar;inhester;solanki]@mps.mpg.de
Received:
16
January
2006
Accepted:
13
April
2006
Aims.We study the possibility of applying tomographic techniques in order to reconstruct the 3D magnetic field configuration in the solar corona. Our simulations are based on data which can be obtained from longitudinal Zeeman-effect (or from Faraday rotation) measurements obtained during a solar rotation.
Methods.The Zeeman effect provides essentially the integrated line-of-sight
component of the magnetic field. The reconstruction problem relates
to a family of similar problems termed vector tomography. For
inversion of this type problems it is known that the curl-free part of a
vector field cannot be reconstructed from the integrated along line-of-sight
data. To remove the resulting ambiguity of the reconstruction we
include the additional constraint, , into the
inversion similar to smoothing constraints in Tikhonov regularization problems.
Results.It is shown that Zeeman data obtained from vantage points in the ecliptic plane alone is sensitive only to certain magnetic field structures. For a full reconstruction it is necessary either to have also observations from viewing directions at higher heliographic latitudes, or to combine the longitudinal Zeeman-effect data with observations that provide the transverse component of the field, e.g. from the Hanle effect.
Key words: Sun: corona / Sun: magnetic fields / Sun: infrared / polarization
© ESO, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.