AI 中文总结
研究利用JWST噪声模型等预测其能搜寻有卫星和自转扁率的凌日系外巨行星数量，如对特定恒星周围行星，单次凌星观测在一定条件下可探测到相关特征，产量受多种因素影响，成功搜寻需普查行星及降低仪器和恒星相关影响。
AI 中文摘要
利用詹姆斯·韦布空间望远镜（JWST）的观测原则上可通过凌星光曲线的细微畸变探测巨系外行星的卫星和自转扁率。最有利的行星预计处于宽轨道（约0.3天文单位以上），在那里卫星和快速自转更易在潮汐演化中留存。目前尚无明确探测报告。本文利用JWST噪声模型、解析可探测性标度、巨行星发生率和盖亚星表预测有足够有利特性以实现可靠探测的系统数量。对于围绕0.9至1.6太阳质量恒星运行的行星以及基于已证明的JWST性能的噪声模型，单次凌星观测若倾角通常约10°以上，应能在几个已知系统及约10个待发现系统中探测到类似木星的自转扁率。若木卫三大小的卫星普遍存在，类似数量的系统有利于其探测。若纳入更低质量宿主恒星或JWST能实现光子极限性能，产量可增至数十或数百个系统。1至10小时时间尺度上的时间相关噪声会强烈抑制产量；百万分之几十的噪声本底就足以在许多其他方面有利的系统中隐藏扁率或卫星。因此，成功的搜寻既需要更完整地普查长周期凌日系外巨行星，也需要低水平的仪器系统误差和恒星变化。
英文摘要
Observations with the {\it James Webb Space Telescope} (JWST) can, in principle, detect moons and rotational oblateness of giant exoplanets through subtle distortions of transit light curves. The most favorable planets are expected to be on wide orbits ($\gtrsim$0.3~AU) where moons and rapid rotation are more likely to survive tidal evolution. No unambiguous detections have yet been reported. Here, we forecast the number of systems with sufficiently favorable properties to allow for secure detections, using JWST noise models, analytic detectability scalings, giant-planet occurrence rates, and the Gaia star catalog. For planets orbiting 0.9--1.6$\,M_\odot$ stars and a noise model based on demonstrated JWST performance, single-transit observations should be capable of detecting Jupiter-like rotational oblateness in several known systems and of order 10 systems yet to be discovered, if obliquities are typically $\gtrsim$10$^\circ$. A similar number of systems are favorable for Ganymede-sized moons, if such moons are common. The yields can increase to tens or hundreds of systems if lower-mass host stars are included or if JWST can achieve photon-limited performance. Time-correlated noise on 1--10 hr timescales can strongly suppress these yields; a noise floor of a few tens of parts per million is enough to hide oblateness or moons in many otherwise favorable systems. Successful searches will therefore require both a more complete census of long-period transiting giant planets and low levels of instrumental systematics and stellar variability.
Comments23 pages, 12 figures, 3 tables, accepted by ApJL
