Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A three-dimensional magnetic topological phase   We use photoemission spectroscopy to discover the first topological magnet in
three dimensions, the material Co$_2$MnGa.

25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th