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arXiv · 2110.11434

Constraints on magnetic field and particle content in blazar jets through optical circular polarization

I. Liodakis·D. Blinov·S. B. Potter·F. M. Rieger
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Abstract

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.

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I. Liodakis, D. Blinov, S. B. Potter, F. M. Rieger. 2021-10-21. Constraints on magnetic field and particle content in blazar jets through optical circular polarization. https://doi.org/10.1093/mnrasl%2Fslab118

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