Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fluorescent C II* 1335A emission spectroscopically resolved in a galaxy
  at z = 5.754   We report the discovery of the first spectroscopically resolved C II /C II*
1334, 1335A doublet in the Lyman-break galaxy J0215-0555 at z = 5.754. The
separation of the resonant and fluorescent emission channels was possible
thanks to the large redshift of the source and long integration time, as well
as the small velocity width of the feature, 0.6 +- 0.2A. We model this emission
and find that at least two components are required to reproduce the combination
of morphologies of C II* emission, C II absorption and emission, and
Lyman-alpha emission from the object. We suggest that the close alignment
between the fluorescence and Lyman-alpha emission could indicate an ionisation
escape channel within the object. While the faintness of such a C II /C II*
doublet makes it prohibitively difficult to pursue for similar systems with
current facilities, we suggest it can become a valuable porosity diagnostic in
the era of JWST and the upcoming generations of ELTs.

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The categories of this paper are: comp-gas
2
The categories of this paper are: math
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
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The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn