利用GHOST/Gemini South对超热木星WASP-178b进行高分辨率昼侧光谱观测
High-Resolution Dayside Spectroscopy of the Ultra-Hot Jupiter WASP-178b with GHOST/Gemini South
AI总结：
研究人员利用GHOST/Gemini South获取WASP-178b的高分辨率昼侧光谱，以8.3σ显著性证实其昼侧大气热反转，补充了超热木星大气相关观测数据。
AI中文摘要：
我们利用Gemini South天文台的双子座高分辨率光学光谱仪（GHOST）获取了超热木星WASP-178b的高分辨率昼侧光谱。观测覆盖了食前后的轨道相位，总时长约9小时，是首次公开的WASP-178b大气高分辨率光学昼侧发射光谱，补充了此前的近红外昼侧光谱研究。我们通过多普勒互相关技术，以8.3σ的高显著性探测到中性铁发射，证实其昼侧大气存在热反转，同时检测到中性硅和钙发射的迹象。我们还对其他大气物种进行了模型注入/恢复测试，结果显示若模型能准确表征该行星大气，则本次研究中搜索的大多数物种预计无法被探测到。最后，我们将结果与此前研究结合，表明中性硅的试探性探测补充了现有空间观测，并为超热木星大气中硅的探测增添了新的数据点。本次高分辨率观测为WASP-178b的昼侧提供了重要信息，有助于揭示三维大气过程及超热木星大气中的极端条件。
英文摘要：
We present high-resolution dayside spectroscopy of the ultra-hot Jupiter WASP-178b obtained with the Gemini High-resolution Optical SpecTrograph (GHOST) at the Gemini South Observatory. The observations cover pre- and post-eclipse orbital phases, lasting approximately 9 hours in total, and represent the first published high-resolution optical dayside emission spectroscopy of WASP-178b's atmosphere, complementing previous near-infrared dayside spectroscopy. We verify the presence of a thermal inversion in the dayside atmosphere with a high-significance (8.3$σ$) detection of neutral iron emission via the Doppler cross-correlation technique, alongside hints of neutral Si and Ca emission. We also carry out model injection/recovery tests for other atmospheric species, which indicate that we do not expect to detect the majority of species searched for in this work, assuming our models are accurate representations of the planet's atmosphere. Finally, we place our results into context with previous work, showing how our tentative detection of neutral Si complements existing space-based observations and adds a new data point to previous detections of Si in ultra-hot Jupiter atmospheres. Our high-resolution observations provide important context about the dayside of WASP-178b, shedding light on 3D atmospheric processes and the extreme conditions present in ultra-hot Jupiter atmospheres.
