Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electron distributions in X-Ray plasmas: spectral diagnostics with the
  3s/3d line ratio in Fe XVII   Efforts to benchmark astrophysical observations with X-ray laboratory
measurements have been stymied by observed and measured differences of up to a
factor of two in the ratio '3s/3d' of Fe XVII lines at ~17 \AA and ~15 \AA
respectively. Using the electron distribution function (EDF) as a new physical
parameter, we compute the Fe XVII line ratios and account for these
differences. Based on large-scale relativistic close coupling calculations
using the Breit-Pauli R-matrix method, revealing the precise effect of
resonances in collisional excitation, we employ collisional-radiative models
using cross sections convolved with both the Gaussian and the Maxwellian EDF.
Comparison with astrophysical observations and laboratory measurements
demonstrates that (a) the 3s/3d line ratio depends not only on the EDF but also
on the electron temperature/energy of the source, (b) plasma conditions in
experimental measurements and astrophysical observations may be quite
different, and (c) departure from a Maxwellian should manifest itself in, and
be used as a diagnostics of, particle distributions in plasmas.

5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
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The categories of this paper are: eess
13
The categories of this paper are: quant-ph
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The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th