High-resolution atmospheric retrievals of WASP-121b transmission spectroscopy with ESPRESSO: Consistent relative abundance constraints across multiple epochs and instruments
High-resolution atmospheric retrievals of WASP-121b transmission spectroscopy with ESPRESSO: Consistent relative abundance constraints across multiple epochs and instruments
复制标题
使用 ESPRESSO 对 WASP-121b 透射光谱进行高分辨率大气反演：跨多个时代和仪器的一致相对丰度约束
DOI：
10.1093/mnras/stac3388
复制
发表时间：
2023
影响因子：
4.8
通讯作者：
Ernst
中科院分区：
文献类型：
--
作者：
Maguire;Cathal; Gibson;Neale P.; Nugroho;Stevanus K.; Ramkumar;Swaetha ; Fortune;Mark ; Merritt;Stephanie R. ; de Mooij;Ernst
高分辨率透射谱的最新进展为表征凌日系外行星的大气层提供了新的途径。高分辨率互相关光谱学允许分子/原子的明确检测。它还被用来绘制早晚肢体物种丰度的大气动力学和纵向变化图。我们提供了多个岩石系外行星的甚大望远镜(VLT)/Echelle光谱仪和超热木星WASP-121b的稳定光谱观测(Epresso)观测，从中我们一致地限制了所有观测中各种中性金属的相对丰度，同时解释了传统数据处理技术造成的系外行星信号的失真。我们还约束了行星轨道速度和T-P分布。我们使用WASP-121b的VLT/紫外线和视觉回声光谱仪(UVES)透射谱将我们的丰度限制与之前的限制进行了比较，发现我们的结果在两次观测之间是一致的，也与之前在WASP-121b大气中检测到的物种的恒星值一致。我们的检索框架也可以用于识别潜在的外层物种，导致扩展的吸收特征超出了Wasp-121b(ReqRL∼1.3Rp)的过境等效罗氏限制。Hα、FeII和CaII延伸到高海拔地区(分别为1.54Rp±0.04Rp、1.17Rp±0.01Rp和2.52Rp±0.34Rp)，与文献值基本一致。我们在多个高分辨率观测上的约束的一致性是对我们的模型过滤和恢复框架以及大气在几个月/年的时间尺度上的稳定性的有力验证，并可能使我们能够从未来对系外大气的地面观测中推断行星的形成过程。
Recent progress in high-resolution transmission spectroscopy has offered new avenues in which to characterize the atmospheres of transiting exoplanets. High-resolution cross-correlation spectroscopy allows for the unambiguous detection of molecules/atoms. It has also been used to map both atmospheric dynamics and longitudinal variations in the abundance of species across the morning and evening limbs. We present multiple Very Large Telescope (VLT)/Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO) observations of the ultrahot Jupiter WASP-121b, from which we constrain relative abundances of various neutral metals consistently across all observations, whilst accounting for the distortion of the exoplanet’s signal caused by traditional data processing techniques. We also constrain planetary orbital velocities andT–Pprofiles. We compare our abundance constraints with previous constraints using VLT/Ultraviolet and Visual Echelle Spectrograph (UVES) transmission spectroscopy of WASP-121b, and find our results to be consistent between observations, and also in agreement with stellar values for species previously detected in the atmosphere of WASP-121b. Our retrieval framework can also be used to identify potential exospheric species, resulting in extended absorption features beyond the transit equivalent Roche limit of WASP-121b (ReqRL∼ 1.3Rp). Hα, Feii, and Caiiwere found to extend to high altitudes (1.54 ± 0.04Rp, 1.17 ± 0.01Rp, and 2.52 ± 0.34Rp, respectively), which are broadly consistent with literature values. The consistency of our constraints across multiple high-resolution observations is a strong validation of our model filtering and retrieval framework, as well as the stability of the atmosphere over the time-scales of months/years, and could allow for planet formation processes to be inferred from future ground-based observations of exoplanetary atmospheres.