Clouds, Brightening and Multiplicity Across the L Dwarf/T Dwarf Transition
arXiv:0810.0570 · doi:10.1063/1.3099158
Abstract
The transition between the two lowest-luminosity spectral classes of brown dwarfs--the L dwarfs and T dwarfs--is traversed by nearly all brown dwarfs as they cool over time. Yet distinct features of this transition, such as the "J-band bump" and an unusually high rate of multiplicity, remain outstanding problems, although evidence points to condensate cloud evolution as a critical component. Using a Monte Carlo population simulation that incorporates the empirical spectral properties of unresolved brown dwarfs in magnitude-limited samples, I demonstrate that the J-band bump and enhanced multiplicity naturally emerge from a short timescale of photospheric cloud dissipation. This timescale may help constrain future evolutionary models exploring the cloud dissipation process.
4 pages, 9 figures, contribution to Cool Stars 15 (AIP format)