Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: New developments in the GALPROP CR propagation model   The GALPROP cosmic-ray (CR) propagation model has been extended to three
dimensions including the effects of stochastic SNR sources, a comprehensive
cross-section database, and nuclear reaction networks. A brief description of
the new code is given and some illustrative results for the distribution of CR
protons presented. Results for electrons and gamma rays are given in an
accompanying paper.

2
The categories of this paper are: math
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph