Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Synergy between professional and amateur astronomers   Since the CCD technique became financially reachable for amateur astronomers,
they can cover topics of professional science. Mainly in the time-domain
astronomy, such as variable star research, their help is invaluable. We focus
on cooperation between amateur and professional astronomers in the Czech
Republic, give some examples of successful projects and propose new programs
that can benefit from such cooperation and bring high-quality results.

30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc