Probing the gas that builds planets: Results from the JWST MINDS program

TL;DR

This study uses JWST infrared observations to analyze the chemical composition of gas in the inner regions of protoplanetary disks, revealing diverse chemical signatures linked to disk structure and stellar type.

Contribution

It provides new observational data on the chemical diversity of planet-forming disks around different star types using JWST's MIRI instrument.

Findings

Disks show diverse spectra, with some rich in H2O and others in CO2.

Disks around very low-mass stars are dominated by hydrocarbons like C2H2.

Inner disk chemistry is linked to physical structures and processes like radial drift.

Abstract

Infrared observations with JWST open up a new window into the chemical composition of the gas in the inner disk (<few au) where planets are built. Results from the MIRI GTO program MINDS (PI: Th. Henning, co-PI: I. Kamp) are presented for several disks around T Tauri and lower-mass stars. A large diversity in spectra is found. Some disks are very rich in H2O lines whereas other disks show prominent CO2. The spectra of disks around very low-mass stars (<0.3 MSun, late-M type stars like Trappist-1) are dominated by C2H2 and other hydrocarbon features including those of benzene, suggesting volatile C/O>1. Together these data point to a rich chemistry in the inner regions that is linked to the physical structure of these disks (e.g., dust traps) and that may be affected by processes such as radial drift of icy pebbles from the outer to the inner disk.