Discovery of a 0 . 15 ′ ′ Binary Brown

Use of the highly sensitive Hokupa'a curvature wavefront sensor has allowed for the first time direct adaptive optics (AO) guiding on brown dwarfs and VLM stars (SpT = M7 − L2). An initial survey of 9 such objects discovered one 0.15 ′′ binary (2MASSJ 1426316+155701). The companion is about half as bright as the primary (∆K = 0.61 ± 0.05,∆H = 0.70 ± 0.05) and has even redder colors H − K = 0.59 ± 0.14 than the primary. The blended spectrum of the binary has been previously determined to be M9.0. We modeled a blend of an M8.5 template and a L1-L3 template reproducing a M9.0 spectrum in the case of ∆K = 0.61 ± 0.05,∆H = 0.70 ± 0.05. These spectral types also match the observed H-K colors of each star. Based the previously observed low space motion and H α activity we assign an age of 0.8