Poster Abstracts

Name/Affiliation:  Daniella C. Bardalez Gagliuffi (UCSD)

Title:  Bridging the gap on tight separation brown dwarf binaries

Abstract:
Multiplicity is a key statistic for understanding the formation of very low mass (VLM) stars and brown dwarfs. Currently, the separation distribution of VLM binaries remains poorly constrained at small separations (< 1 AU), leading to uncertainty in the overall binary fraction. We approach this problem by searching for late M/early L plus T dwarf spectral binaries whose combined light spectra exhibit distinct peculiarities, making their identification independent of separation. We define a set of spectral indices designed to identify these systems, and use a spectral template fitting method to confirm and characterize spectral binary (SB) candidates from a library of 738 spectra from the SpeX Prism Spectral Libraries. We present ten new binary candidates, confirm two previously reported candidate and rule out two previously identified candidates, all with primary and secondary spectral types between M7-L7 and L8-T8 respectively. We find that blue L dwarfs are the primary contaminants in our sample and propose a method for segregating these sources. If confirmed by follow-up observations, these systems may potentially add to the growing list of tight separation binaries, giving further insight into brown dwarf formation scenarios.