标题： MOJAVE耀变体中的法拉第旋转：3C 273是一个案例研究 显示英文标题

标题： Faraday rotation in the MOJAVE blazars: 3C 273 a case study

摘要： 射电偏振观测可以揭示活动星系核在秒差距尺度喷流中的磁场结构。 我们利用甚长基线阵列进行了多频段调查，对伽马射线耀变体3C 273进行了观测，以研究大量喷流中的法拉第旋转。 我们的观测再次确认了3C 273中的横向旋转测量梯度。 首次观察到该梯度穿过零点，这进一步表明喷流中存在螺旋状磁场和脊鞘结构。 我们认为与以前时期的差异是由于在我们的观测中，喷流的不同部分被照亮。 显示英文摘要

摘要： Radio polarimetric observations of Active Galactic Nuclei can reveal the magnetic field structure in the parsec-scale jets of these sources. We have observed the gamma-ray blazar 3C 273 as part of our multi-frequency survey with the Very Long Baseline Array to study Faraday rotation in a large sample of jets. Our observations re-confirm the transverse rotation measure gradient in 3C 273. For the first time the gradient is seen to cross zero which is further indication for a helical magnetic field and spine-sheath structure in the jet. We believe the difference to previous epochs is due to a different part of the jet being illuminated in our observations.