Self-gravitating disc candidates around massive young stars
Abstract
There have been several recent detections of candidate Keplerian discs around massive young protostars. Given the relatively large disc-to-star mass ratios in these systems, and their young ages, it is worth investigating their propensity to becoming self-gravitating. To this end, we compute self-consistent, semi-analytic models of putative self-gravitating discs for five candidate disc systems. Our aim is not to fit exactly the observations, but to demonstrate that the expected dust continuum emission from marginally unstable self-gravitating discs can be quite weak, due to high optical depth at the mid-plane even at millimetre wavelengths. In the best cases, the models produce ‘observable’ disc masses within a factor of <1.5 of those observed, with mid-plane dust temperatures comparable to measured temperatures from molecular line emission. We find in two cases that a self-gravitating disc model compares well with observations. If these discs are self-gravitating, they satisfy the conditions for disc fragmentation in their outer regions. These systems may hence have as-yet-unresolved low-mass stellar companions, and are thus promising targets for future high angular resolution observations.
Citation
Forgan , D H , Ilee , J D , Cyganowski , C J , Brogan , C L & Hunter , T R 2016 , ' Self-gravitating disc candidates around massive young stars ' , Monthly Notices of the Royal Astronomical Society , vol. 463 , no. 1 , pp. 957-964 . https://doi.org/10.1093/mnras/stw1917
Publication
Monthly Notices of the Royal Astronomical Society
Status
Peer reviewed
ISSN
1365-2966Type
Journal article
Rights
© 2016, the Author(s). This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at mnras.oxfordjournals.org / https://doi.org/10.1093/mnras/stw1917
Description
DHF gratefully acknowledges support from the ECOGAL project, grant agreement 291227, funded by the European Research Council under ERC-2011-ADG. JDI gratefully acknowledges support from the DISCSIM project, grant agreement 341137, funded by the European Research Council under ERC-2013-ADG. CJC acknowledges support from STFC grant ST/M001296/1.Collections
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