Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hyperfine Interaction in Quarkonia   The recent experimental developments in the measurement of hyperfine
splittings in the bound states of charmonium and bottomonium are presented.
Their implications for the hyperfine interactions in the heavy quark systems
are discussed.

3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom