Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Towards an improved understanding of the relative scintillation
  efficiency of nuclear recoils in liquid xenon
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
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
21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex