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arXiv · 1607.03771

Evidence for quasi-periodic oscillations in the optical polarization of the blazar PKS 2155-304

N. W. Pekeur·A. R. Taylor·S. B. Potter·R. C. Kraan-Korteweg
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Abstract

Evidence for the presence of quasi-periodic oscillations (QPOs) in the optical polarization of the blazar PKS 2155-304, during a period of enhanced gamma-ray brightness, is presented. The periodogram of the polarized flux revealed the existence of a prominent peak at $T\sim 13$ min, detected at >99.7% significance, and $T\sim 30$ min, which was nominally significant at >99%. This is the first evidence of QPOs in the polarization of an active galactic nucleus, potentially opening up a new avenue of studying this phenomenon.

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N. W. Pekeur, A. R. Taylor, S. B. Potter, R. C. Kraan-Korteweg. 2016-07-13. Evidence for quasi-periodic oscillations in the optical polarization of the blazar PKS 2155-304. https://doi.org/10.1093/mnrasl/slw129

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