Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modelling the recurrent nova U Scorpii in quiescence   VLT and SALT spectroscopy of U Sco were obtained $\sim$18 and $\sim$30 months
after the 2010 outburst. From these spectra the accretion disc is shown to take
at least 18 months to become fully reformed. The spectral class of the
companion is constrained to be F8$^{+5}_{-6}$\,IV-V at the 95% confidence level
when the irradiated face of the companion is visible.

15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn