Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diagnostics of active and eruptive prominences through hydrogen and
  helium lines modelling   In this study we show how hydrogen and helium lines modelling can be used to
make a diagnostic of active and eruptive prominences. One motivation for this
work is to identify the physical conditions during prominence activation and
eruption. Hydrogen and helium lines are key in probing different parts of the
prominence structure and inferring the plasma parameters. However, the
interpretation of observations, being either spectroscopic or obtained with
imaging, is not straightforward. Their resonance lines are optically thick, and
the prominence plasma is out of local thermodynamic equilibrium due to the
strong incident radiation coming from the solar disk. In view of the shift of
the incident radiation occurring when the prominence plasma flows radially, it
is essential to take into account velocity fields in the prominence diagnostic.
Therefore we need to investigate the effects of the radial motion of the
prominence plasma on hydrogen and helium lines. The method that we use is the
resolution of the radiative transfer problem in the hydrogen and helium lines
out of local thermodynamic equilibrium. We study the variation of the computed
integrated intensities in H and He lines with the radial velocity of the
prominence plasma. We can confirm that there exist suitable lines which can be
used to make a diagnostic of the plasma in active and eruptive prominences in
the presence of velocity fields.

13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol