论文标题
TOI-1696：附近的M4矮人，带有$ 3r_ \ oplus $ Planet在Neptunian沙漠
TOI-1696: a nearby M4 dwarf with a $3R_\oplus$ planet in the Neptunian desert
论文作者
论文摘要
We present the discovery and validation of a temperate sub-Neptune around the nearby mid-M dwarf TIC 470381900 (TOI-1696), with a radius of $3.09 \pm 0.11 \,R_\oplus$ and an orbital period of $2.5 \,\rm{days}$, using a combination of TESS and follow-up observations using ground-based telescopes.从苔丝，马斯喀特，马斯喀特3，sinistro和开普敦的多波段光度法的联合分析证实，过境信号是可观的，并且是精制的轨道灭虫。使用双子座/'支持的高分辨率成像和Subaru/ird的高分辨率光谱证实，恒星没有恒星伴侣或背景来源。 The spectroscopic observations with IRD and IRTF/SpeX were used to determine the stellar parameters, and found the host star is an M4 dwarf with an effective temperature of $T_{eff} = 3185 \pm 76\,\rm{K}$ and a metallicity of [Fe/H] $=0.336 \pm 0.060 \，\ rm {dex} $。从IRD测得的径向速度将行星质量的$ 2 $ - $σ$上限设置为$ 48.8 \，m_ \ oplus $。较大的半径比（$ r_p/r_ \ star \ sim 0.1 $）和相对明亮的NIR幅度（$ j = 12.2 \，\ rm {mag} $）使该星球成为进一步的后续观察的有吸引力的目标。 TOI-1696b是迄今发现的最高传输光谱指标的属于Neptunian沙漠的行星之一，使其成为JWST与JWST进行大气特征的有趣候选者。
We present the discovery and validation of a temperate sub-Neptune around the nearby mid-M dwarf TIC 470381900 (TOI-1696), with a radius of $3.09 \pm 0.11 \,R_\oplus$ and an orbital period of $2.5 \,\rm{days}$, using a combination of TESS and follow-up observations using ground-based telescopes. Joint analysis of multi-band photometry from TESS, MuSCAT, MuSCAT3, Sinistro, and KeplerCam confirmed the transit signal to be achromatic as well as refined the orbital ephemeris. High-resolution imaging with Gemini/'Alopeke and high-resolution spectroscopy with the Subaru/IRD confirmed that there are no stellar companions or background sources to the star. The spectroscopic observations with IRD and IRTF/SpeX were used to determine the stellar parameters, and found the host star is an M4 dwarf with an effective temperature of $T_{eff} = 3185 \pm 76\,\rm{K}$ and a metallicity of [Fe/H] $=0.336 \pm 0.060 \,\rm{dex}$. The radial velocities measured from IRD set a $2$-$σ$ upper limit on the planetary mass to be $48.8 \,M_\oplus$. The large radius ratio ($R_p/R_\star \sim 0.1$) and the relatively bright NIR magnitude ($J=12.2 \,\rm{mag}$) make this planet an attractive target for further followup observations. TOI-1696b is one of the planets belonging to the Neptunian desert with the highest transmission spectroscopy metric discovered to date, making it an interesting candidate for atmospheric characterizations with JWST.
