Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Oxygen, {\alpha}-element and iron abundance distributions in the inner
  part of the Galactic thin disc   We derived elemental abundances in 27 Cepheids, the great majority situated
within a zone of Galactocentric distances ranging from 5 to 7 kpc. One star of
our sample, SU Sct, has a Galactocentric distance of about 3 kpc, and thus
falls in a poorly investigated region of the inner thin disc. Our new results,
combined with data on abundances in the very central part of our Galaxy taken
from literature, show that iron, magnesium, silicon, sulfur, calcium and
titanium LTE abundance radial distributions, as well as NLTE distribution of
oxygen reveal a plateau-like structure or even positive abundance gradient in
the region extending from the Galactic center to about 5 kpc.

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The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin