Fig. 4: Contribution of opacity sources to the best-fitting model with injected SO2.
From: Early Release Science of the exoplanet WASP-39b with JWST NIRSpec G395H
a, The lowest χ2/N best-fitting model (PICASO in Fig. 3) with an injected abundance of 10−5.6 (VMR) SO2. We also show this model with a selection of the anticipated absorbing species and the cloud opacity removed to indicate their contributions to the model. The inclusion of SO2 in the model decreases the χ2/N from 1.08 (shown in Fig. 3) to 1.02, resulting in a 4.8σ detection (see Extended Data Table 3). b–e, The effect of removing the corresponding molecular opacity from the spectrum (shaded region). Our best-fit model is also affected by minor opacities from CO, H2S, OCS and CH4, although their spectral features cannot be robustly detected in the spectrum. We show a model without CO and CH4 in a to demonstrate this, with the minor contribution by CO also highlighted in e.
