arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2110.03340astro-ph.EP
收藏

TRAPPIST-1:transit的动态分析-谐振链的时序变化和起源

TRAPPIST-1: Dynamical analysis of the transit-timing variations and origin of the resonant chain

Jean Teyssandier, Anne-Sophie Libert, Eric Agol

摘要:

我们分析的解决方案,从最近发表的后验分布的TRAPPIST-1系统,其中包括七个地球大小的行星似乎是在一个共振链周围的红矮星。我们发现,所有的行星同时在两个行星和三个行星的共振,除了最里面的一对两个行星的共振角循环。通过频率分析,我们强调,过境定时变化(TTV)信号具有一系列的共同周期从几天到几十年不等,这也是目前在系统的动力学变量的变化。较短的周期(例如,TTV特征时间尺度为1.3年)与两行星平均运动共振有关,而更长的周期则来自三行星共振。通过使用$N$体模拟迁移力,我们探索的起源TRAPPIST-1的共振链,并发现,对于特定的光盘条件下,一个链的共振-类似于所观察到的-可以形成准确地再现所观察到的TTV。我们的分析表明,虽然4年收集的观测数据包含了关于两行星共振动力学的关键信息,但对TRAPPIST-1的进一步监测将很快提供三体共振的特征,特别是目前最佳拟合解所预期的3.3和5.1年周期。DVDs观测将有助于评估最里面的一对行星是否确实共振(其接近8:5共振的解释具有挑战性),因此对形成情景提供了额外的限制。

英文摘要:

We analyze solutions drawn from the recently published posterior distribution of the TRAPPIST-1 system, which consists of seven Earth-size planets appearing to be in a resonant chain around a red dwarf. We show that all the planets are simultaneously in two-planet and three-planet resonances, apart from the innermost pair for which the two-planet resonant angles circulate. By means of a frequency analysis, we highlight that the transit-timing variation (TTV) signals possess a series of common periods varying from days to decades, which are also present in the variations of the dynamical variables of the system. Shorter periods (e.g., the TTVs characteristic timescale of 1.3 yr) are associated with two-planet mean-motion resonances, while longer periods arise from three-planet resonances. By use of $N$-body simulations with migration forces, we explore the origin of the resonant chain of TRAPPIST-1 and find that for particular disc conditions, a chain of resonances - similar to the observed one - can be formed which accurately reproduces the observed TTVs. Our analysis suggests that while the 4-yr collected data of observations hold key information on the two-planet resonant dynamics, further monitoring of TRAPPIST-1 will soon provide signatures of three-body resonances, in particular the 3.3 and 5.1 yr periodicities expected for the current best-fit solution. dditional observations would help to assess whether the innermost pair of planets is indeed resonant (its proximity to the 8:5 resonance being challenging to explain), and therefore give additional constraints on formation scenarios.

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。

↑