论文标题
K2矮人V471 Tau的磁场演变
Magnetic field evolution of the K2 dwarf V471 Tau
论文作者
论文摘要
对黯然失色的二进制系统V471 tau的观察表明，初级蚀的时间以明显的周期性方式变化。有了越来越多的证据表明磁性活性的K2矮人成分可能是驱动日食时序变化（ETV）的原因，在整个预测的〜35岁活性周期中，有必要监测恒星，从而推理了观察到的ETV。我们通过分析了2014年12月和2015年1月在加拿大 - 弗朗西·霍瓦伊望远镜上通过esspadons获得的光谱图数据来为这一目标做出贡献。使用Zeeman-Doppler Imaging，我们重建了亮度含量含量含量的亮度含量，并在K2 Dwarf的K2 dwarf表面上分布。与使用相同代码进行的恒星的先前层析成像重建相比，我们探测了ETVS周期的新阶段，为将来的工作提供了新的约束，以探索在K2矮星中运行的磁性机制是否确实能够诱导观察到的V471 TAU的ETV。
Observations of the eclipsing binary system V471 Tau show that the time of the primary eclipses varies in an apparent periodic way. With growing evidence that the magnetically active K2 dwarf component might be responsible for driving the eclipse timing variations (ETVs), it is necessary to monitor the star throughout the predicted ~ 35 yr activity cycle that putatively fuels the observed ETVs. We contribute to this goal with this paper by analysing spectropolarimetric data obtained with ESPaDOnS at the Canada-France-Hawaii Telescope in December 2014 and January 2015. Using Zeeman-Doppler Imaging, we reconstruct the distribution of brightness inhomogeneities and large-scale magnetic field at the surface of the K2 dwarf. Compared to previous tomographic reconstructions of the star carried out with the same code, we probe a new phase of the ETVs cycle, offering new constraints for future works exploring whether a magnetic mechanism operating in the K2 dwarf star is indeed able to induce the observed ETVs of V471 Tau.
