The optical polarization plane of some blazars occasionally exhibits smooth hundred degree long rotations. Multiple theoretical models have been proposed to explain the nature of such events. A deterministic origin of these rotations, however, remains uncertain. We aim to find repeating patterns of flares in gamma-ray light curves of blazars, which accompany optical polarization plane rotations. Such patterns have been predicted to occur by one of the models explaining this phenomenon. For the blazar 3C 279, where multiple polarization plane rotations have been reported in the literature, we obtain the Fermi-LAT gamma-ray light curve and analyse its intervals adjacent to polarization plane rotations. We find a complex characteristic pattern of flares in the gamma-ray light curve that is repeated during periods adjacent to three large amplitude EVPA rotation events in 3C 279. We discover a ‘hidden EVPA rotation’, which can only be seen in the relative Stokes parameters plane and that occurred simultaneously with the fourth repetition of the pattern. This finding strongly favours the hypothesis of emission features propagating in the jet as the reason of optical polarization plane rotations. Furthermore, it is compatible with the hypothesis of a sheath in the jet comprised of more slowly propagating emission features.

中文翻译：

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耀变体 3C 279 光变曲线中伽马射线耀斑的重复模式

一些耀变体的光学偏振面偶尔会出现平滑的数百度长旋转。已经提出了多种理论模型来解释此类事件的性质。然而，这些旋转的确定性起源仍然不确定。我们的目标是在耀变体的伽马射线光曲线中找到重复的耀斑模式，伴随着光学偏振平面旋转。一种解释这种现象的模型已经预测到这种模式会发生。对于 blazar 3C 279，文献中已经报道了多个偏振平面旋转，我们获得了 Fermi-LAT 伽马射线光曲线并分析了其与偏振平面旋转相邻的间隔。我们在 3C 279 中的三个大振幅 EVPA 旋转事件附近的周期内重复出现的伽马射线光曲线中复杂的耀斑特征模式。我们发现了“隐藏的 EVPA 旋转”，这只能在相对斯托克斯中看到参数平面和与模式的第四次重复同时发生。这一发现强烈支持在射流中传播的发射特征作为光学偏振平面旋转的原因的假设。此外，它与射流中的鞘层由传播更慢的发射特征组成的假设相一致。这一发现强烈支持在射流中传播的发射特征作为光学偏振平面旋转的原因的假设。此外，它与射流中的鞘层由传播更慢的发射特征组成的假设相一致。这一发现强烈支持在射流中传播的发射特征作为光学偏振平面旋转的原因的假设。此外，它与射流中的鞘层由传播更慢的发射特征组成的假设相一致。