Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observations of the forward scattering Hanle effect in the Ca i 4227
  {\AA} line   Chromospheric magnetic fields are notoriously diffcult to measure. The
chromospheric lines are broad, while the fields are producing a minuscule
Zeeman-effect polarization. A promising diagnostic alternative is provided by
the forward-scattering Hanle effect, which can be recorded in chromospheric
lines such as the He i 10830 {\AA} and the Ca i 4227 {\AA} lines. We present a
set of spectropolarimetric observations of the full Stokes vector obtained near
the center of the solar disk in the Ca i 4227 {\AA} line with the ZIMPOL
polarimeter at the IRSOL observatory.We detect a number of interesting
forward-scattering Hanle effect signatures, which we model successfully using
polarized radiative transfer. Here we focus on the observational aspects, while
a separate companion paper deals with the theoretical modeling.

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The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
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The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org