The salty emission of the intermediate-mass AGB star OH 30.1 -0.7

Abstract

We analyse continuum and molecular emission, observed with ALMA, from the dust-enshrouded intermediate-mass AGB star OH 30.1 -0.7. We find a secondary peak in the continuum maps, "feature B", separated by 4.6" from the AGB star, which corresponds to a projected separation of $1.8\times 10^4$ 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, SO${}_2$, 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 (3 = 1), NaCl (up to 3 = 4) and KCl (up to 3 = 2), and emission from low energy levels in the mid to outer envelope, as traced by SO${}_2$. The CO emission is abruptly truncated around 3.5" or 14,000 au from the continuum peak, suggesting that mass loss at a high rate may have commenced as little as 2800 years ago.

arXiv commentAccepted for publication in MNRAS

References in corpus (45)

• Complex Chemistry in Star-Forming Regions: An Expanded Gas-Grain Warm-up Chemical Model
• The Cologne Database for Molecular Spectroscopy, CDMS, in the Virtual Atomic and Molecular Data Centre, VAMDC
• Trigonometric Parallaxes Of High-Mass Star Forming Regions: Our View Of The Milky Way
• A three-phase chemical model of hot cores: the formation of glycine
• Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)
• The largest oxigen bearing organic molecule repository
• Exploring Molecular Complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)
• Formation of complex organic molecules in hot molecular cores through nondiffusive grain-surface and ice-mantle chemistry
• Weeds: a CLASS extension for the analysis of millimeter and sub-millimeter spectral surveys
• Re-exploring Molecular Complexity with ALMA (ReMoCA): Interstellar detection of urea
• Molecules at z=0.89: A 4-mm-rest-frame absorption line survey toward PKS 1830-211
• Rotational spectroscopy, tentative interstellar detection, and chemical modelling of N-methylformamide
• Formation of Complex Organic Molecules in Cold Interstellar Environments through non-diffusive grain-surface and ice-mantle chemistry
• Complex organic molecules in the Galactic Centre: the N-bearing family
• Tracing shocks and photodissociation in the Galactic center region
• Exploring molecular complexity with ALMA (EMoCA): Alkanethiols and alkanols in Sagittarius B2(N2)
• Spectral Line Identification and Modelling (SLIM) in the MAdrid Data CUBe Analysis (MADCUBA) package: An interactive software for data cube analysis
• Formation and recondensation of complex organic molecules during protostellar luminosity outbursts
• Discovery in space of ethanolamine, the simplest phospholipid head group
• Thiols in the ISM: first detection of HC(O)SH and confirmation of C${}_2$H${}_5$SH
• The complex chemistry of hot cores in Sagittarius B2(N): Influence of cosmic-ray ionization and thermal history
• Prebiotic precursors of the primordial RNA world in space: Detection of NH${}_2$OH
• Abundant Z-cyanomethanimine in the interstellar medium: paving the way to the synthesis of adenine
• Cloud-cloud collision as drivers of the chemical complexity in Galactic Centre molecular clouds
• Propargylimine in the laboratory and in space: millimetre-wave spectroscopy and first detection in the ISM
• Precursors of fatty alcohols in the ISM: Discovery of n-propanol
• Probing the chemical complexity of amines in the ISM: detection of vinylamine (C${}_2$H${}_3$NH${}_2$) and tentative detection of ethylamine (C${}_2$H${}_5$NH${}_2$)
• Infrared H3+ and CO Studies of the Galactic Core: GCIRS 3 and GCIRS 1W
• First detection of C${}_2$H${}_5$NCO in the ISM and search of other isocyanates towards the G+0.693-0.027 molecular cloud
• Methylamine and other simple N-bearing species in the hot cores NGC 6334I MM1-3
• N-bearing complex organics toward high-mass protostars: Constant ratios pointing to formation in similar pre-stellar conditions across a large mass range
• Detection of the cyanomidyl radical (HNCN): a new interstellar species with the NCN backbone
• Detection of New Methylamine (CH${}_3$NH${}_2$) Sources: Candidates for Future Glycine Surveys
• Interstellar detection and chemical modeling of iso-propanol and its normal isomer
• The quest for complex molecules in space: Laboratory spectroscopy of n-butyl cyanide, n-C4H9CN, in the millimeter wave region and its astronomical search in Sagittarius B2(N)
• Resolving desorption of complex organic molecules in a hot core: Transition from non-thermal to thermal desorption or two-step thermal desorption?
• Organic molecules, ions, and rare isotopologues in the remnant of the stellar-merger candidate, CK Vulpeculae (Nova 1670)
• Molecular remnant of Nova 1670 (CK Vulpeculae): I. Properties and enigmatic origin of the gas
• Rotational spectroscopy of mono-deuterated oxirane ($c$-C${}_2$H${}_3$DO) and its detection towards IRAS 16293$-$2422 B
• The Sub-millimeter Rotational Spectrum of Ethylene Glycol up to 890 GHz and Application to ALMA Band 10 Spectral Line Data of NGC 6334I
• Millimeter- and submillimeter-wave spectroscopy of thioformamide and interstellar search toward Sgr B2(N)
• Rotational spectroscopy of isotopic oxirane, $c$-C${}_2$H${}_4$O
• Toward a global model of the interactions in low-lying states of methyl cyanide: rotational and rovibrational spectroscopy of the $v_4=1$ state and tentative interstellar detection of the $v_4=v_8=1$ state in Sgr B2(N)
• Laboratory spectroscopic study of the ${}^{15}$N isotopomers of cyanamide, H${}_2$NCN, and a search for them toward IRAS 16293$-$2422 B
• (Sub-)millimeter-wave spectroscopy of gauche-propanal

Cited by in corpus (3)

• Reexploring Molecular Complexity with ALMA: Insights into chemical differentiation from the molecular composition of hot cores in Sgr B2(N2)
• The rotation-tunneling spectrum of 3-hydroxypropenal and confirmation of its detection toward IRAS 16293$-$2422 B
• Nitrogen- and nitrogen-oxygen-bearing organic molecules in comet 67P/Churyumov-Gerasimenko: An untargeted investigation