Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The Star Formation Region NGC 6530: distance, ages and Initial Mass
  Function
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an