Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: On the reconstruction of diagonal elements of density matrix of quantum
  optical states by on/off detectors
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas