Distinguishing Binary from Single L/T Transition Dwarfs Using Only Photometry

TL;DR

This study uses photometric data to distinguish binary brown dwarfs from single ones during the L/T transition, revealing that binaries are generally brighter and aiding in identifying unresolved binaries.

Contribution

It introduces a photometric method to differentiate binary from single brown dwarfs in the L/T transition using mean absolute magnitudes and color analysis.

Findings

Binaries are 1-2 sigma brighter than singles at the same color.

Photometry can help identify unresolved binary brown dwarfs.

Implications for spectral blend candidates across luminosity range.

Abstract

Brown dwarfs undergo little change in near-infrared luminosity while cooling from L to T spectral types, making the L/T transition (spectral types $\approx$L9--T6) an ideal region to examine the differences in photometry for binary and single brown dwarfs. We investigated the mean absolute magnitudes for binaries and singles with parallaxes as a function of J-K color in the L/T transition. Overall, binaries are on average $1-2\sigma$ brighter than singles of the same color. We discuss the implications for candidate binaries that are apparent spectral blends which span a broad range of luminosities, from the brightest binaries to the faintest singles.