Danilovich, T., Richards, A.M.S., Van de Sande, M. et al. (17 more authors) (2025) The salty emission of the intermediate-mass AGB star OH 30.1−0.7. Monthly Notices of the Royal Astronomical Society, 526 (1). pp. 684-713. ISSN 0035-8711
Abstract
We analyse continuum and molecular emission, observed with Atacama Large Millimetre/submillimetre Array, from the dust-enshrouded intermediate-mass asymptotic giant branch (AGB) star OH 30.1−0.7. We find a secondary peak in the continuum maps, ‘feature B’, separated by 4.6 arcsec from the AGB star, which corresponds to a projected separation of 1.8 × 10⁴ au, placing a lower limit on the physical separation. This feature is most likely composed of cold dust and is likely to be ejecta associated with the AGB star, though we cannot rule out that it is a background object. The molecular emission we detect includes lines of CO, SiS, CS, SO₂, NS, NaCl, and KCl. We find that the NS emission is off centre and arranged along an axis perpendicular to the direction of feature B, indicative of a UV-emitting binary companion (e.g. a G-type main sequence star or hotter), perhaps on an eccentric orbit, contributing to its formation. However, the NaCl and KCl emission constrain the nature of that companion to not be hotter than a late B-type main-sequence star. We find relatively warm emission arising from the inner wind and detect several vibrationally excited lines of SiS (v = 1), NaCl (up to v = 4), and KCl (up to v = 2), and emission from low-energy levels in the mid to outer envelope, as traced by SO₂. The CO emission is abruptly truncated around 3.5 arcsec or 14 000 au from the continuum peak, suggesting that mass loss at a high rate may have commenced as little as 2800 yr ago.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2024 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. |
Keywords: | stars: AGB and post-AGB, circumstellar matter, stars: individual: OH 30.1−0.7 |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemistry (Leeds) > Physical Chemistry (Leeds) |
Funding Information: | Funder Grant number STFC (Science and Technology Facilities Council) ST/T000287/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 13 Dec 2024 15:00 |
Last Modified: | 13 Dec 2024 15:00 |
Status: | Published |
Publisher: | Oxford University Press (OUP) |
Identification Number: | 10.1093/mnras/stae2584 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:220709 |