Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Particle Physics Masterclasses for the International Day of Women and
  Girls in Science   On the occasion of the UN International Day of Women and Girls in Science
(February 11) Masterclass activities were launched by the International
Particle Physics Outreach Group to support and promote the access of women and
girls to science education and research activities. Universities and research
laboratories organised 10 Masterclasses for girls on February 10 and 11, with
participation from Barcelona, Cagliari, Cosenza, Heidelberg, Madrid, Paris,
Prague, Rio de Janeiro, and Sao Paulo. About 300 girls participated in the
events and analysed LHC data while being tutored by female scientists. Three
video conferences with CERN were held where the girls could talk to CERN women
scientists and learn about the careers of these role models.

27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math