Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: HEGRA Contributions to the 28th International Cosmic Ray Conference   This preprint encompasses thirteen individual contributions of the HEGRA
collaboration to the 28th International Cosmic Ray conference in Tsukuba,
Japan. The papers report on results on M87, M31, H1426+428, Mkn421,
1ES1959+650, Scan of the TeV sky, Performance of the system, GeV sources, 54
AGN, and SN1006

3
The categories of this paper are: physics
19
The categories of this paper are: eess
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an