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تسجيل مستخدم جديدEvidence for quasi-periodic oscillations in the optical polarization of the blazar PKS 2155-304
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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 $Tsim 13$ min, detected at >99.7% significance, and $Tsim 30$ 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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An analysis is presented of the optical polarimetric and multicolour photometric ($BVRJ$) behaviour of the blazar PKS 2155$-$304 during an outburst in 2010. This flare develops over roughly 117 days, with a flux doubling time $tau sim 11$ days that i
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