论文标题
陆地行星的Hubble WFC3光谱L〜98-59〜C \＆D：没有证据表明透明氢主导的原发性大气
Hubble WFC3 Spectroscopy of the Terrestrial Planets L~98-59~c \& d: No Evidence for a Clear Hydrogen Dominated Primary Atmosphere
论文作者
论文摘要
附近的明亮的M-warf恒星L〜98-59有三个地面大小的行星。表征周围大气的一个挑战是，尚不清楚它们是否具有任何气氛。在这里，我们使用HST/WFC3的G141 Grism的近红外光谱数据报告了L〜98-59〜C和L〜98-59〜d的大气的研究。我们可以拒绝以氢气和氦气为主的清晰气氛的假设，其置信度为$ \ sim $ 3〜Sigma的两个行星。因此，他们可能具有不透明的云层层的主要氢为主气氛，或者失去了主要的氢为主导的气氛，并重新建立了次要的薄氛围，或者根本没有气氛。我们无法使用当前的HST数据区分两个行星的这些方案。与JWST的未来观察能够确认L〜98-59〜C和D附近的大气的存在，并确定其组成。
The nearby bright M-dwarf star L~98-59 has three terrestrial-sized planets. One challenge remaining in characterizing atmospheres around such planets is that it is not known a priori whether they possess any atmospheres. Here we report the study of the atmospheres of L~98-59~c and L~98-59~d using the near-infrared spectral data from the G141 grism of HST/WFC3. We can reject the hypothesis of a clear atmosphere dominated by hydrogen and helium at a confidence level of $\sim$ 3~sigma for both planets. Thus they may have a primary hydrogen-dominated atmosphere with an opaque cloud layer, or have lost their primary hydrogen-dominated atmosphere and re-established a secondary thin atmosphere, or have no atmosphere at all. We cannot distinguish between these scenarios for the two planets using the current HST data. Future observations with JWST would be capable of confirming the existence of atmospheres around L~98-59~c and d and determining their compositions.
