Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Science with the new generation high energy gamma- ray experiments   This Conference is the fifth of a series of Workshops on High Energy Gamma-
ray Experiments, following the Conferences held in Perugia 2003, Bari 2004,
Cividale del Friuli 2005, Elba Island 2006. This year the focus was on the use
of gamma-ray to study the Dark Matter component of the Universe, the origin and
propagation of Cosmic Rays, Extra Large Spatial Dimensions and Tests of Lorentz
Invariance.

25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph