Bibcode
Orozco-Suárez, D.; Katsukawa, Y.
Bibliographical reference
The Astrophysical Journal, Volume 746, Issue 2, article id. 182 (2012).
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2
2012
Journal
Citations
17
Refereed citations
15
Description
This paper presents results from the analysis of high signal-to-noise
ratio spectropolarimetric data taken at four heliocentric angles in
quiet-Sun internetwork regions with the Hinode satellite. First, we find
that the total circular and total linear polarization signals vary with
heliocentric angle, at least for fields with large polarization signals.
We also report changes on the Stokes V amplitude asymmetry histograms
with viewing angle for fields weaker than 200 G. Then, we subject the
data to a Milne-Eddington inversion and analyze the variation of the
field vector probability density functions with heliocentric angle.
Weak, highly inclined fields permeate the internetwork at all
heliocentric distances. For fields weaker than 200 G, the distributions
of field inclinations peak at 90° and do not vary with viewing
angle. The inclination distributions change for fields stronger than 200
G. We argue that the shape of the inclination distribution for weak
fields partly results from the presence of coherent, loop-like magnetic
features at all heliocentric distances and not from tangled fields
within the field of view. We also find that the average magnetic field
strength is about 180 G (for 75% of the pixels) and is constant with
heliocentric angle. The average vertical and horizontal magnetic field
components are 70 and 150 G. The latter (former) is slightly greater
(smaller) near the limb. Finally, the ratio between the horizontal and
vertical components of the fields ranges from ~1 for strong fields to
~3.5 for weak fields, suggesting that the magnetic field vector is not
isotropically distributed within the field of view.
Related projects
Magnetism, Polarization and Radiative Transfer in Astrophysics
Magnetic fields pervade all astrophysical plasmas and govern most of the variability in the Universe at intermediate time scales. They are present in stars across the whole Hertzsprung-Russell diagram, in galaxies, and even perhaps in the intergalactic medium. Polarized light provides the most reliable source of information at our disposal for the
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