Bayesian Analysis for Remote Biosignature Identification on exoEarths (BARBIE). IV. Analyzing CO 2 Detections in the Near-IR to Determine the Long-wavelength Cutoff for the Habitable Worlds Observatory Coronagraph

作者：Celeste Hagee, Natasha Latouf, Avi M. Mandell, Michael D. Himes, Michael Dane Moore, Geronimo L. Villanueva · 发表于：The Astronomical Journal · 年份：2026 · DOI：10.3847/1538-3881/ae3c81 · 被引用次数：2 · 研究领域：Stellar, planetary, and galactic studies、Planetary Science and Exploration、Space Science and Extraterrestrial Life

Abstract We present our analysis of how the detectability of carbon dioxide (CO 2 ) on an Earth-like planet varies with respect to signal-to-noise ratio (SNR), wavelength, and molecular abundance. Using the Bayesian Analysis for Remote Biosignature Identification on exoEarths methodology, we can determine the optimal long-wavelength cutoff for the future Habitable Worlds Observatory coronagraph. We test 25 evenly spaced 20% bandpasses between 0.8 and 2.0 μ m, and simulate data spanning a range of SNRs and molecular abundance to analyze the relationship between wavelength and detectability for different planetary archetypes. We examine abundance levels from varying Earth epochs and a Venus-like archetype to investigate how detectability would change throughout the evolution of a rocky planet. Here, we present our results on the planetary conditions and technological requirements to strongly detect CO 2 . In addition, we analyze the degeneracy of CO 2 with carbon monoxide (CO), methane (CH 4 ), and water (H 2 O). We determine that any abundance of CO does not achieve strong detections and that CH 4 and H 2 O play a pivotal role in the ability to detect CO 2 . We conclude that the optimal long-wavelength cutoff for the Habitable Worlds Observatory coronagraph should be 1.68 μ m.