论文标题
WASP-74行星系统的倾斜测量和大气表征
Obliquity measurement and atmospheric characterization of the WASP-74 planetary system
论文作者
论文摘要
我们使用高分辨率光谱harps-n和多色同时的成像器muscat2介绍了热木星黄蜂（$ t_ \ mathrm {eq} \ sim $ 1860 K）的新的过境观测。我们完善行星及其宿主星的轨道特性，并首次测量其倾斜度。恒星自旋轴和行星轨道轴之间测得的天空投影角与与宿主星的赤道良好对准的轨道兼容（$λ= 0.77 \ pm0.99 \ pm0.99 \ mathrm {deg} $）。我们无法在其高分辨率传输光谱中检测到H $α$或任何其他原子光谱特征的任何吸收特征，这是由于线芯处的S/N。尽管先前对WASP-74 B大气中的TIO和Vo气体存在强烈的光学吸收剂的主张，但新的基于地面的光度法与先前报道的先前报道的文献观察结果的重新分析相结合，显示出，文献的观察结果表明，低分辨率透射光谱频谱在低分辨率的透射频谱中比单独预期的雷利散射更陡。
We present new transit observations of the hot Jupiter WASP-74 b ($T_\mathrm{eq} \sim$ 1860 K) using the high-resolution spectrograph HARPS-N and the multi-colour simultaneous imager MuSCAT2. We refine the orbital properties of the planet and its host star, and measure its obliquity for the first time. The measured sky-projected angle between the stellar spin-axis and the planet's orbital axis is compatible with an orbit well-aligned with the equator of the host star ($λ= 0.77\pm0.99 \mathrm{deg}$). We are not able to detect any absorption feature of H$α$, or any other atomic spectral features, in its high-resolution transmission spectra due to low S/N at the line cores. Despite previous claims regarding the presence of strong optical absorbers such TiO and VO gases in the atmosphere of WASP-74 b, the new ground-based photometry combined with a reanalysis of previously reported observations from the literature shows a slope in the low-resolution transmission spectrum steeper than expected from Rayleigh scattering alone.
