Shenton, R.G. orcid.org/0000-0003-1715-2310, Houghton, R.J. orcid.org/0000-0002-9723-1088, Oudmaijer, R.D. orcid.org/0000-0001-7703-3992 et al. (4 more authors) (2023) The RMS survey: a census of massive YSO multiplicity in the K −band. Monthly Notices of the Royal Astronomical Society. stad3755. ISSN 0035-8711
Abstract
Close to 100 per cent of massive stars are thought to be in binary systems. The multiplicity of massive stars seems to be intrinsically linked to their formation and evolution, and Massive Young Stellar Objects are key in observing this early stage of star formation. We have surveyed three samples totalling hundreds of MYSOs (>8M⊙) across the Galaxy from the RMS catalogue, using UKIDSS and VVV point source data, and UKIRT K −band imaging to probe separations between 0.8-9 arcsec (approx 1000-100,000 au). We have used statistical methods to determine the binary statistics of the samples, and we find binary fractions of 64 ± 4 per cent for the UKIDSS sample, 53 ± 4 per cent for the VVV sample, and 49 ± 8 per cent for the RMS imaging sample. Also we use the J − and K −band magnitudes as a proxy for the companion mass, and a significant fraction of the detected systems have estimated mass ratios greater than 0.5, suggesting a deviation from the capture formation scenario which would be aligned with random IMF sampling. Finally, we find that YSOs located in the outer Galaxy have a higher binary fraction than those in the inner Galaxy. This is likely due to a lower stellar background density than observed towards the inner Galaxy, resulting in higher probabilities for visual binaries to be physical companions. It does indicate a binary fraction in the probed separation range of close to 100 per cent without the need to consider selection biases.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Keywords: | binaries: general, stars: formation, stars: massive, stars: pre-main-sequence |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Astrophysics (Leeds) |
Funding Information: | Funder Grant number STFC (Science and Technology Facilities Council) ST/T000287/1 STFC (Science and Technology Facilities Council) ST/X001016/1 STFC (Science and Technology Facilities Council) ST/P00041X/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 07 Dec 2023 12:17 |
Last Modified: | 07 Dec 2023 12:17 |
Status: | Published online |
Publisher: | Oxford University Press |
Identification Number: | 10.1093/mnras/stad3755 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:206307 |