Towards a Comprehensive Understanding of Brown Dwarf Atmospheres

University Of California-Santa Cruz, Santa Cruz CA

Investigators

Abstract

Brown dwarfs are objects that sit at the boundary between stars and planets. Although they form like stars, they do not have hydrogen fusion, so they cool over billions of years down to temperatures similar to those of planets. By studying the the infrared heat radiation given off by brown dwarfs, we can understand the physics and chemistry and their atmospheres. This project involves the work of graduate students and high school students, who will receive training in advanced computational techniques, which will allow them to create computer models of brown dwarf atmospheres. These results will be compared to observations made from large telescopes in order to determine the physical properties within brown dwarf atmospheres. The proposal team will carry out a significant expansion of the phase space of brown dwarf model atmospheres. They will investigate the role of metallicity, non-solar carbon-to-oxygen ratios, varied cloud thickness, cloud coverage fraction, surface gravity, and other factors in shaping brown dwarf spectra. This extensive grid of radiative-convective "forward models" will map out the phase space of brown dwarf atmospheric chemistry and physics. For the first time we will gain a quantitative understanding of the reasons behind mismatches between spectral observations and models. The bulk of the science will be performed by a graduate student, in concert with high school interns who will be mentored each summer.