Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Advances of plasma diagnostics with high-resolution spectroscopy of
  stellar coronae   X-ray emission from cool stars is an important tracer for stellar activity.
The X-ray luminosity reflects different levels of activity and covers four
orders of magnitude in stars of spectral types M-F. Low spectral resolution
provided by X-ray observations of stellar coronae in the past allowed the
determination of temperature distributions and elemental abundances making use
of atomic databases (listing line emissivities and bremsstrahlung continuum for
a given temperature structure). The new missions XMM-Newton and Chandra carry
X-ray gratings providing sufficient spectral resolution to measure the fluxes
of strategic emission lines. I describe the different approaches applicable to
low-resolution and high-resolution spectra, especially focusing on the new
grating spectra with X-ray lines. From only a few lines it is possible to
determine plasma temperatures and associated densities, to check for any
effects from resonant scattering, and to identify particular abundance
anomalies. Line-based temperature- and density measurements represent only a
fraction of the total plasma, but the pressure environment of different
fractions can be probed simply by selection of specific lines. Selected results
are presented covering all aspects of line-based analyses.

33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys