Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High-resolution, high-sensitivity, ground-based solar spectropolarimetry
  with a new fast imaging polarimeter   Context. Remote sensing of weak and small-scale solar magnetic fields is of
utmost relevance for a number of important open questions in solar physics.
This requires the acquisition of spectropolarimetric data with high spatial
resolution (0.1 arcsec) and low noise (1e-3 to 1e-5 of the continuum
intensity). The main limitations to obtain these measurements from the ground,
are the degradation of the image resolution produced by atmospheric seeing and
the seeing-induced crosstalk (SIC). Aims. We introduce the prototype of the
Fast Solar Polarimeter (FSP), a new ground-based, high-cadence polarimeter that
tackles the above-mentioned limitations by producing data that are optimally
suited for the application of post-facto image restoration, and by operating at
a modulation frequency of 100 Hz to reduce SIC. Results. The pnCCD camera
reaches 400 fps while keeping a high duty cycle (98.6 %) and very low noise
(4.94 erms). The modulator is optimized to have high (> 80%) total polarimetric
efficiency in the visible spectral range. This allows FSP to acquire 100
photon-noise-limited, full-Stokes measurements per second. We found that the
seeing induced signals present in narrow-band, non-modulated, quiet-sun
measurements are (a) lower than the noise (7e-5) after integrating 7.66 min,
(b) lower than the noise (2.3e-4) after integrating 1.16 min and (c) slightly
above the noise (4e-3) after restoring case (b) by means of a multi-object
multi-frame blind deconvolution. In addition, we demonstrate that by using only
narrow-band images (with low SNR of 13.9) of an active region, we can obtain
one complete set of high-quality restored measurements about every 2 s.

31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs