Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of charm and beauty production in deep inelastic ep
  scattering from decays into muons at HERA   The production of charm and beauty quarks in ep interactions has been
measured with the ZEUS detector at HERA for squared four-momentum exchange
Q^2>20 GeV^2, using an integrated luminosity of 126 pb^{-1}. Charm and beauty
quarks were identified through their decays into muons. Differential cross
sections were measured for muon transverse momenta p_T^{\mu}>1.5 GeV and
pseudorapidities -1.6<\eta^{\mu}<2.3, as a function of p_T^{\mu}, \eta^{\mu},
Q^2 and Bjorken x. The charm and beauty contributions to the proton structure
function F_2 were also extracted. The results agree with previous measurements
based on independent techniques and are well described by QCD predictions.

13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph