Evidence for a Photoevaporated Circumbinary Disk in Orion

We have found a photoevaporated disk in the Orion Nebula that includes a wide binary. HST ACS observations of the proplyd 124–132 show two pointlike sources separated by 0.15″, or about 60 AU at the distance of Orion. The two sources have nearly identical I and z magnitudes. We analyze the brightest component, source N, comparing the observed magnitudes with those predicted using a 1 Myr Baraffe/NextGen isochrone with different accretion luminosities and extinctions. We find that a low-mass (≃0.04 M☉) brown dwarf ~1 Myr old with mass accretion rate log Ṁ ≃ −10.3, typical for objects of this mass, and about 2 mag of visual extinction provides the best fit to the data. This is the first observation of a circumbinary disk undergoing photoevaporation and, if confirmed by spectroscopic observations, the first direct detection of a wide substellar pair still accreting and enshrouded in its circumbinary disk.