Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Blazar variability - expect the unexpected   Despite significant progress in both data taking and the development of
theory, blazars keep offering surprises. While many frequency bands are now
covered by long-term monitoring efforts on at least a few selected sources,
blazars remain unpredictable and the same source may exhibit vastly different
behaviors. Here, an overview is given about four selected sources, namely 3C
279, PKS 2155-304, PKS 1510-089 and CTA 102. All of them exhibited, indeed,
highly unexpected events.

26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th