Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Highlights of Crystal Ball Physics   Differential and total cross sections are presented for pi- - and K- -induced
reactions on a proton target leading to all-neutral final states. Also shown
are rates for rare and upper limits for forbidden eta-meson decays to test
Chiral Perturbation Theory, the pi0-pi0 interactions and C and CP invariance.

26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat