Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Constraints on magnetic field and particle content in blazar jets
  through optical circular polarization   Polarization offers a unique view in the physical processes of astrophysical
jets. We report on optical circular polarization observations of two famous
blazars, namely 3C 279 and PKS 1510-089, at high linearly polarized states.
This is the first time PKS 1510-089 is observed in optical circular
polarization. While only upper limits can be extracted from our observing
campaign, the non-detection of optical circular polarization allows us to
provide meaningful constraints on their magnetic field strength and jet
composition. We find that high-energy emission models requiring high magnetic
field strength and a low positron fraction can be excluded.

12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
19
The categories of this paper are: eess
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org