2024
Ref: CTALK-2025-0065

Impact of Magma-Atmosphere Coupling on Sub-Neptune Populations

Hakim, Kaustubh


Talk presented at COST PLANETS Kick-Off Meeting, Torun, Poland on 2024-07-10

Abstract: Hot sub-Neptunes (equilibrium temperatures > 1000 K) are commonly found in the galaxy. Recent modelling efforts suggest that magma-atmosphere coupling of small exoplanets, i.e., rocky exoplanets and sub-Neptunes, strongly impacts the atmospheric chemistry, enriching the atmosphere in refractory element- bearing gases, e.g., SiO, SiH4. To determine atmospheric chemistry, we implement a new state-of-the-art code, atmodeller, that models an equilibrium chemistry reaction network. Based on the calculations for atmosphere chemistry in the Si-O-H system with mass conservation for H, we can classify sub-Neptune populations into steam worlds, hydrogen worlds, and silicon worlds. We will further show the strong impact of non-ideal gas behaviour and gas solubility in magma on these populations. These populations should exhibit distinct atmospheric signatures that are detectable with JWST transmission and emission spectroscopy.

Funding: FED-tWIN/STELLA/Prf-2021-022


The record appears in these collections:
Conference Contributions & Seminars > Conference Talks > Contributed Talks
Royal Observatory of Belgium > Reference Systems & Planetology



 Record created 2025-02-04, last modified 2025-02-04