标题： 短周期行星对Ca II H & K辐射的调制 显示英文标题

标题： Modulation of Ca II H & K Emission by Short-Period Planets

摘要： 我们发现，在五个轨道周期在3到4天之间的类51 Peg星中，有四个星的Ca II H&K反演结构存在调制现象。 我们在K核观察到了两种效应：（1）约1%水平上的3埃的宽变化；（2）三个反演特征中的每一个都出现约0.5埃（约1-3%）的变化。 夜间的变异性在H和K中都是一致的。从精度优于20米/秒的微小径向速度测量中，提取了最新的相位。 反演的增强往往在行星子午线上最大，这可能意味着恒星外部层与行星磁层之间存在磁场相互作用。 这些高信噪比（连续区每像素500）和高分辨率（R=110,000）的数据太少，无法确认轨道同步化。 显示英文摘要

摘要： We have detected modulation of the Ca II H&K reversal structure in four out of five 51 Peg-type stars whose planets have orbital periods between 3 and 4 days. We observe two effects in the K-core: (1) a broad 3-A variation at ~1% level and (2) changes on a scale of 0.5 A (~1-3%) in each of the three reversal features. The nightly variations are coherent in both H and K. From differential radial velocities measured to better than 20 m/s, up-to-date phases were extracted. The enhancements in the reversals tend to be greatest at the sub-planetary points which may imply that there is a magnetic interaction between the star's outer layers and the magnetosphere of the planet. These high-S/N (500 per pixel in the continuum) and high-resolution (R = 110,000) data are too few to confirm orbital synchronization.