论文标题
HD 56414 b：温暖的海王星过渡A型星星
HD 56414 b: A Warm Neptune Transiting an A-type Star
论文作者
论文摘要
我们报告了TESS数据中的发现和HD 56414 B（又称TOI-1228 B）的发现，Neptune-Size（$ r _ {\ rm p} = 3.71 \ 3.71 \ pm 0.20 \，r_ \ oplus $）具有29天的年轻人（年龄为$ 420 $ 420 $ 420 $ pm pm pm Myr = $ 420南部连续观看区。 HD 56414是最热的恒星之一（$ t _ {\ rm eff} = 8500 \ pm 150 \，{\ rm k} $）托管已知的Sub-Jovian星球。 HD 56414 B位于行星半径中热海王星沙漠的边界上 - 降压器显发磁通空间，这表明该行星可能正在遭受质量损失。为了探讨这一点，我们采用了一个光蒸发模型，该模型结合了A型星的近距离紫外线连续发射。我们发现，如果其质量为$ \ ge 8 \，m_ \ oplus $，则该星球可以在A型恒星的典型1-GYR主序列寿命上保留其大部分气氛。我们的模型还预测，带有质量$ <14 \，m_ \ oplus $的海王星大小的行星容易对1 Gyr超过1 Gyr的总大气剥离感到敏感，这暗示着先前在FGKM型星周围观察到的热海王星沙漠，可能会延伸到A型星星。
We report the discovery in TESS data and validation of HD 56414 b (a.k.a. TOI-1228 b), a Neptune-size ($R_{\rm p} = 3.71 \pm 0.20\, R_\oplus$) planet with a 29-day orbital period transiting a young (Age = $420 \pm 140$ Myr) A-type star in the TESS southern continuous viewing zone. HD 56414 is one of the hottest stars ($T_{\rm eff} = 8500 \pm 150 \, {\rm K}$) to host a known sub-Jovian planet. HD 56414 b lies on the boundary of the hot Neptune desert in planet radius -- bolometric insolation flux space, suggesting that the planet may be experiencing mass loss. To explore this, we apply a photoevaporation model that incorporates the high near ultraviolet continuum emission of A-type stars. We find that the planet can retain most of its atmosphere over the typical 1-Gyr main sequence lifetime of an A-type star if its mass is $\ge 8 \, M_\oplus$. Our model also predicts that close-in Neptune-size planets with masses $< 14 \, M_\oplus$ are susceptible to total atmospheric stripping over 1 Gyr, hinting that the hot Neptune desert, which has been previously observed around FGKM-type stars, likely extends to A-type stars.
