Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The virtual photon structure at HERA   An overview is given of the ongoing measurement at HERA of the parton
structure of the photon, as a function of its virtuality. Preliminary ZEUS
results show disagreement with an NLO QCD calculation.

21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph