Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The energy of waves in the photosphere and lower chromosphere: III.
  Inversion setup for Ca II H spectra in local thermal equilibrium   The Ca II H line is one of the strongest lines in the solar spectrum and
provides continuous information on the solar atmosphere from the photosphere to
the lower chromosphere. We describe an inversion approach that reproduces
observed Ca II H spectra assuming LTE. We developed an inversion strategy based
on the SIR code. The approach uses a two-step procedure with an archive of
pre-calculated spectra to fit the line core and a subsequent iterative
modification to improve the fit in the line wing. Simultaneous spectra in the
630nm range can optionally be used to fix the continuum temperature. The method
retrieves 1D temperature stratifications neglecting lateral radiative
transport. LOS velocities are included by an empirical approach. An archive of
about 300.000 pre-calculated spectra is more than sufficient to reproduce the
line core of observed Ca II H spectra both in quiet Sun and in active regions.
The final thermodynamical stratifications match observed and best-fit spectra
to a level of about 0.5 (1) % of Ic in the line wing (core). Inversion schemes
based on pre-calculated spectra allow one a reliable and relatively fast
retrieval of solar properties from observed chromospheric spectra. The approach
can be easily extended to an 1D NLTE case by a simple exchange of the
pre-calculated archive spectra.

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The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: stat
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
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The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an