Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Galactic Evolution of Beryllium and Oxygen   We discuss the early evolution of beryllium and oxygen in our Galaxy by
comparing abundances of these elements for halo and disk metal-poor stars.
Both, O and Be rise as we go progressively to more metal-rich stars, showing a
slope 0.41 +-0.09 ([Be/O] vs [Fe/H]) for stars with [Fe/H] < -1. This
relationship provides an observational constraint to the actually proposed
Galactic Cosmic Ray theories.

31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
3
The categories of this paper are: physics