Shaping the Brown Dwarf Desert: Constraints from Turbulent Fragmentation Dr. Robert T. Fisher, Peter Jumper, and Deivid Ribeiro

What is the Brown Dwarf Desert? The notable absence of brown dwarfs within five times the Earth-Sun distance from their central star (Grether and Lineweaver 2004)

Why Do We Care? Improve understanding of angular momentum transfer in the star formation process – Scaled-up planets? – Scaled-down stars?

Past Research Brown dwarfs migrating into the central stars proposed Credit: Phil Armitage

Gravitational Fragmentation Model Core: star-forming gaseous cloud Models deal with the formation of two stars from the core Mass and angular momentum of stars dependent on the core ε * = (M 1 + M 2 )/M core ε J = J/J core

Turbulent Fragmentation Core angular momentum comes from turbulence Net angular momentum is nonzero Credit: (Seinfeld 1986)

Methodology Draw masses from the initial mass function Gaussian random field gives turbulence and angular momentum Calculate orbital parameters

Research Progress Conducting verification by reproducing results of an earlier paper Troubleshooting New initial mass function code prepared

Future Plans Conduct simulations for 200 brown dwarf – binary systems Analysis of results

Questions?