Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for the decay B0 to gamma gamma   The rare decay B0 -> gamma gamma is searched for in 104 fb^-1 of data,
corresponding to 111 x 10^6 BBar pairs, collected with the Belle detector at
the KEKB asymmetric-energy e+ e- collider. No evidence for the signal is found,
and an upper limit of 6.2 x 10^-7 at 90% confidence level is set for the
corresponding branching fraction.

18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph