An enhanced carbon chemistry in disks around very low-mass stars and brown dwarfs?
Abstract
We present a unique dataset of high-resolution Spitzer/IRS spectra from eight very low-mass star and brown dwarf disks. We report the first detections of ionized neon, molecular hydrogen, carbon dioxide, and water vapor in these disks and show that they have, on average, higher C2H2/HCN and HCN/H2O column density ratios than disks around sun-like stars. These trends may result from an enhanced carbon-to-oxygen ratio in the inner regions of these lowmass disks, which may be linked to a faster formation of icy planetesimals beyond the snow line. We discuss the implications of this finding on the bulk composition and water content of rocky planets that can form around very low-mass stars and brown dwarfs.
- Publication:
-
Search for Life Beyond the Solar System. Exoplanets, Biosignatures & Instruments
- Pub Date:
- March 2014
- Bibcode:
- 2014ebi..conf..2.2P