L 98-59 d is a Super-Earth planet orbiting an M-type star. We performed retrievals on the transmission spectrum of L 98-59 d obtained using NIRSpec G395H during a single transit, from JWST Cycle 1 GTO 1224. The wavelength range of this spectrum allows us to detect the presence of several atmospheric species. We found that the spectrum is consistent with a high mean molecular weight atmosphere. The atmospheric spectrum indicates the possible presence of the sulfur-bearing species H₂S and SO₂, which could hint at active volcanism on this planet if verified by future observations. We also tested for signs of stellar contamination in the spectrum and found signs of unocculted faculae on the star. The tentative signs of an atmosphere on L 98-59 d presented in this work from just one transit bodes well for possible molecular detections in the future, particularly as it is one of the best targets among small exoplanets for atmospheric characterization using JWST.

中文翻译：

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大气反演表明 JWST Nirspec G395H 透射光谱仪在 L98-59 d 存在次生大气和可能的硫物质


L 98-59 d 是一颗围绕 M 型恒星运行的超级地球行星。我们对使用 NIRSpec G395H 在 JWST 第 1 周期 GTO 1224 的单次传输期间获得的 L 98-59 d 的传输光谱进行了检索。该光谱的波长范围使我们能够检测到几种大气物质的存在。我们发现该光谱与高平均分子量大气一致。大气光谱表明可能存在含硫物质 H₂S 和 SO₂，如果未来的观测证实，这可能暗示这颗行星上存在活跃的火山活动。我们还测试了光谱中恒星污染的迹象，并在恒星上发现了未掩蔽的光斑迹象。这项工作中仅从一次凌日呈现的 L 98-59 d 大气的初步迹象预示着未来可能的分子检测，特别是因为它是使用 JWST 进行大气表征的小型系外行星中的最佳目标之一。