The Sonora Substellar Atmosphere Models. V. A Correction to the Disequilibrium Abundance of CO2 for Sonora Elf Owl

2025/05/06 by Nicholas F. Wogan, James Mang, Natasha E. Batalha +7 · 1 voice · 7 citations
Physics and Astronomy · Earth and Planetary Sciences · #Astrophysics and Star Formation Studies #Scientific Research and Discoveries #Atmospheric Ozone and Climate

paper · pdf · doi:10.3847/2515-5172/add407

Abstract

Abstract To aid the interpretation of observations of substellar atmospheres, S. Mukherjee et al. created the Sonora Elf Owl grid of model atmospheres, simulations that accounted for disequilibrium quench chemistry. However, Sonora Elf Owl did not accurately estimate CO 2 quenching because the models quenched the gas with respect to the full atmosphere equilibrium, but CO 2 should have instead been quenched with respect to the disequilibrium (i.e., quenched) abundance of CO. As a result, Sonora Elf Owl under-predicted the CO 2 abundance by several order of magnitude in some instances, an amount that JWST is sensitive to. Here, we release version two of the Sonora Elf Owl grid which has corrected CO 2 concentrations. Additionally, in version two we remove PH 3 as a spectral contributor since our spectra consistently contained too much PH 3 absorption. The new spectra can be found as an update to the original Zenodo postings.

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Discussions

• The reason we do atmospheric modeling is to learn about processes. We found our Elf Owl models didn't predict the CO2 abundance in brown dwarfs correctly. This was a win, we learned something new! IOu [bsky, 8 points, 1 comments]

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