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arXiv · 1403.2026

ALMA Observations of the Orion Proplyds

Rita K. Mann·James Di Francesco·Doug Johnstone·Sean M. Andrews·Jonathan P. Williams·John Bally·Luca Ricci·A. Meredith Hughes·Brenda C. Matthews
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Abstract

We present ALMA observations of protoplanetary disks ("proplyds") in the Orion Nebula Cluster. We imaged 5 individual fields at 856um containing 22 HST-identified proplyds and detected 21 of them. Eight of those disks were detected for the first time at submillimeter wavelengths, including the most prominent, well-known proplyd in the entire Orion Nebula, 114-426. Thermal dust emission in excess of any free-free component was measured in all but one of the detected disks, and ranged between 1-163 mJy, with resulting disk masses of 0.3-79 Mjup. An additional 26 stars with no prior evidence of associated disks in HST observations were also imaged within the 5 fields, but only 2 were detected. The disk mass upper limits for the undetected targets, which include OB stars, theta1Ori C and theta1Ori F, range from 0.1-0.6 Mjup. Combining these ALMA data with previous SMA observations, we find a lack of massive (>3 Mjup) disks in the extreme-UV dominated region of Orion, within 0.03 pc of O-star theta1Ori C. At larger separations from theta1Ori C, in the far-UV dominated region, there is a wide range of disk masses, similar to what is found in low-mass star forming regions. Taken together, these results suggest that a rapid dissipation of disk masses likely inhibits potential planet formation in the extreme-UV dominated regions of OB associations, but leaves disks in the far-UV dominated regions relatively unaffected.

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Rita K. Mann, James Di Francesco, Doug Johnstone, Sean M. Andrews, Jonathan P. Williams, John Bally, Luca Ricci, A. Meredith Hughes, Brenda C. Matthews. 2014-03-09. ALMA Observations of the Orion Proplyds. https://doi.org/10.1088/0004-637x%2F784%2F1%2F82

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