We present 17 transit light curves of seven known warm-Jupiters observed with the CHaracterising ExOPlanet Satellite (CHEOPS). The light curves have been collected as part of the CHEOPS Guaranteed Time Observation (GTO) program that searches for transit-timing variation (TTV) of warm-Jupiters induced by a possible external perturber to shed light on the evolution path of such planetary systems. We describe the CHEOPS observation process, from the planning to the data analysis. In this work, we focused on the timing performance of CHEOPS, the impact of the sampling of the transit phases, and the improvement we can obtain by combining multiple transits together. We reached the highest precision on the transit time of about 13–16 s for the brightest target (WASP-38, G = 9.2) in our sample. From the combined analysis of multiple transits of fainter targets with G ≥ 11, we obtained a timing precision of ∼2 min. Additional observations with CHEOPS, covering a longer temporal baseline, will further improve the precision on the transit times and will allow us to detect possible TTV signals induced by an external perturber.

中文翻译：

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利用暖木星行星 CHEOPS 任务的计时能力

我们展示了用 ExOPlanet 卫星 (CHEOPS) 观测到的七颗已知暖木星的 17 条凌日光曲线。这些光变曲线是作为 CHEOPS 保证时间观测 (GTO) 计划的一部分收集的，该计划旨在寻找由可能的外部扰动引起的暖木星的凌日时间变化 (TTV)，以阐明此类行星系统的演化路径。我们描述了 CHEOPS 观察过程，从规划到数据分析。在这项工作中，我们专注于 CHEOPS 的计时性能、传输阶段采样的影响以及通过将多个传输组合在一起可以获得的改进。对于我们样本中最亮的目标（WASP-38，G = 9.2），我们在大约 13-16 秒的传输时间上达到了最高精度。通过对 G ≥ 11 的较暗目标的多次过境的综合分析，我们获得了约 2 分钟的计时精度。使用 CHEOPS 进行的额外观测，涵盖更长的时间基线，将进一步提高传输时间的精度，并使我们能够检测到由外部扰动引起的可能的 TTV 信号。