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arXiv · 0809.3208

Evidence for a Photoevaporated Circumbinary Disk in Orion

M. Robberto·L. Ricci·N. Da Rio·D. R. Soderblom
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Abstract

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 point-like 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 (\simeq 0.04 M_\odot) brown dwarf ~1 Myr old with mass accretion rate \log\dot{M}\simeq -10.3, typical for objects of this mass, and about 2 magnitudes 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.

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M. Robberto, L. Ricci, N. Da Rio, D. R. Soderblom. 2008-09-18. Evidence for a Photoevaporated Circumbinary Disk in Orion. https://doi.org/10.1086/593183

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