Atmospheric Retrievals Suggest The Presence of a Secondary Atmosphere and Possible Sulfur Species on L 98-59 d from JWST NIRSpec G395H Transmission Spectroscopy
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.
Agnibha Banerjee, Joanna K. Barstow, Amélie Gressier, Néstor Espinoza, David K. Sing, Natalie H. Allen, Stephan M. Birkmann, Ryan C. Challener, Nicolas Crouzet, Carole A. Haswell, Nikole K. Lewis, Stephen R. Lewis, Jingxuan Yang
Comments: Accepted for publication to ApJL
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2408.15707 [astro-ph.EP] (or arXiv:2408.15707v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2408.15707
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Related DOI:
https://doi.org/10.3847/2041-8213/ad73d0
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Submission history
From: Agnibha Banerjee
[v1] Wed, 28 Aug 2024 11:11:14 UTC (5,007 KB)
https://arxiv.org/abs/2408.15707
Astrobiology
