标题： 系外星周尘埃云的凌星光曲线 显示英文标题

标题： The Transit Light Curve of an Exozodiacal Dust Cloud

摘要： 行星嵌入碎片盘中会引力扰动附近的尘埃，并能产生团状的、方位上不对称的围绕恒星的环状结构，这些结构与行星同步旋转。地球在太阳黄道尘埃云中形成了一种这样的结构。在边缘观测系统中，尘埃“团块”随着行星绕恒星运行，周期性地从恒星前方经过，遮挡并前向散射恒星光。在本文中，我们预测了相应掩食信号的形状和大小。为此，我们模拟了由行星伴星扰动的碰撞稳态外黄道尘埃云的尘埃分布。我们研究了由行星的共振捕获导致螺旋进入尘埃形成的尘埃环结构的盘，考虑了不同行星质量、半长轴、尘埃特性和盘质量的情况。我们合成了这些模型的边缘图像，并计算了共振环结构的掩食特征。由尘埃共振环结构产生的掩食光曲线通常表现出两个宽广的掩食最小值，它们领先和滞后于行星掩食。我们发现，嵌入在比我们的黄道尘埃云密集数百倍的盘中的木星质量行星可以产生最大可达$\sim10^{-4}$的共振环结构掩食深度，可能可以用\emph{开普勒}进行探测。由质量大于或小于木星的行星产生的共振环产生较小的掩食深度。对这些掩食信号的观测可能提供外黄道尘埃云不对称程度的上限。 显示英文摘要

摘要： Planets embedded within debris disks gravitationally perturb nearby dust and can create clumpy, azimuthally asymmetric circumstellar ring structures that rotate in lock with the planet. The Earth creates one such structure in the solar zodiacal dust cloud. In an edge-on system, the dust "clumps" periodically pass in front of the star as the planet orbits, occulting and forward-scattering starlight. In this paper, we predict the shape and magnitude of the corresponding transit signal. To do so, we model the dust distributions of collisional, steady-state exozodiacal clouds perturbed by planetary companions. We examine disks with dusty ring structures formed by the planet's resonant trapping of in-spiraling dust for a range of planet masses and semi-major axes, dust properties, and disk masses. We synthesize edge-on images of these models and calculate the transit signatures of the resonant ring structures. The transit light curves created by dusty resonant ring structures typically exhibit two broad transit minima that lead and trail the planetary transit. We find that Jupiter-mass planets embedded within disks hundreds of times denser than our zodiacal cloud can create resonant ring structures with transit depths up to $\sim10^{-4}$, possibly detectable with \emph{Kepler}. Resonant rings produced by planets more or less massive than Jupiter produce smaller transit depths. Observations of these transit signals may provide upper limits on the degree of asymmetry in exozodiacal clouds.