RESOLVED SPECTROSCOPY OF M DWARF/L DWARF BINARIES. IV. DISCOVERY OF AN M9+L6 BINARY SEPARATED BY OVER 100 AU

We report the discovery of a faint L6 +/- 1 companion to the previously known M9 dwarf, 2MASS J01303563-4445411, based on our near-infrared imaging and spectroscopic observations with the 3 m Infrared Telescope Facility SpeX imager/spectrometer. The visual binary is separated by 3.'' 28 +/- 0.'' 05 on the sky at a spectrophotometric distance of 40 +/- 14 pc. The projected physical separation is 130 +/- 50 AU, making it one of the widest very low mass (VLM) field multiples containing a brown dwarf companion. 2MASS J0130-4445 is only one of ten wide VLM pairs and only one of six in the field. The secondary is considerably fainter (Delta K approximate to 2.35 mag) and redder (Delta(J - K-s) approximate to 0.81 dex), consistent with component near-infrared types of M9.0 +/- 0.5 and L6 +/- 1 based on our resolved spectroscopy. The component types suggest a secondary mass well below the hydrogen-burning limit and an age-dependent mass ratio of 0.6-0.9. The system's space motion and spectroscopic indicators suggest an age of 2-4 Gyr while the model-dependent masses and binding energies suggest that this system is unlikely to have formed via dynamical ejection. The age, composition, and separation of the 2MASS J01303563-4445411 system make it useful for tests of VLM formation theories and of condensate cloud formation in L dwarfs.