由系外卫星引起的凌日时间效应
Transit timing effects due to an exomoon
摘要：
随着已知系外行星的数量不断增加，关于这些天体是否拥有卫星系统的问题已经成为人们越来越感兴趣的问题之一。在本文中，我们将探讨过境时间的影响，应检测到由于exomoon和预测一个新的观察。我们首先考虑过境时间变化（TTV），在那里我们更新模型，包括轨道偏心率的影响。我们得出两个关键结论：1）为了保持希尔稳定性，外卫星的轨道频率将始终高于采样频率。因此，无法从TTV可靠地确定系外卫星的周期，只能从一组谐波频率确定。2)TTV振幅与M_S a_S成正比，其中M_S为系外卫星质量，a_S为卫星轨道半长轴。因此，M_S和a_S不能单独确定。我们继续预测一个新的观测由于exoons-过境持续时间变化（TDV）。我们推导出TDV幅度并得出结论，其幅度不仅是可检测的，而且TDV信号将提供两个鲁棒的优点：1）TDV幅度与M_S a_S^{-1/2}成比例，因此TTV和TDV的比率允许单独确定M_S和a_S。2)TDV与TTV信号有90度的相位差，使其成为一种优秀的互补技术。
英文摘要：
As the number of known exoplanets continues to grow, the question as to whether such bodies harbour satellite systems has become one of increasing interest. In this paper, we explore the transit timing effects that should be detectable due to an exomoon and predict a new observable. We first consider transit time variation (TTV), where we update the model to include the effects of orbital eccentricity. We draw two key conclusions: 1) In order to maintain Hill stability, the orbital frequency of the exomoon will always be higher than the sampling frequency. Therefore, the period of the exomoon cannot be reliably determined from TTV, only a set of harmonic frequencies. 2) The TTV amplitude is proportional to M_S a_S where M_S is the exomoon mass and a_S is the semi-major axis of the moon's orbit. Therefore, M_S and a_S cannot be separately determined. We go on to predict a new observable due to exomoons - transit duration variation (TDV). We derive the TDV amplitude and conclude that its amplitude is not only detectable, but the TDV signal will provide two robust advantages: 1) The TDV amplitude is proportional to M_S a_S^{-1/2} and therefore the ratio of TTV and TDV allows for a separate determination of M_S and a_S. 2) TDV has a 90 degrees phase difference to the TTV signal, making it an excellent complementary technique.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
