A major asymmetric ice trap in a planet-forming disk: III. First detection of dimethyl ether

Abstract

The complex organic molecules (COMs) detected in star-forming regions are the precursors of the prebiotic molecules that can lead to the emergence of life. By studying COMs in more evolved protoplanetary disks we can gain a better understanding of how they are incorporated into planets. This paper presents ALMA band 7 observations of the dust and ice trap in the protoplanetary disk around Oph IRS 48. We report the first detection of dimethyl ether (CH3OCH3) in a planet-forming disk and a tentative detection of methyl formate (CH3OCHO). We determined column densities for the detected molecules and upper limits on non-detected species using the CASSIS spectral analysis tool. The inferred column densities of CH3OCH3 and CH3OCHO with respect to methanol (CH3OH) are of order unity, indicating unusually high abundances of these species compared to other environments. Alternatively, the 12CH3OH emission is optically thick and beam diluted, implying a higher CH3OH column density and a smaller emitting area than originally thought. The presence of these complex molecules can be explained by thermal ice sublimation, where the dust cavity edge is heated by irradiation and the full volatile ice content is observable in the gas phase. This work confirms the presence of oxygen-bearing molecules more complex than CH3OH in protoplanetary disks for the first time. It also shows that it is indeed possible to trace the full interstellar journey of COMs across the different evolutionary stages of star, disk, and planet formation.

arXiv commentAccepted to A&A - 20th Jan 2022

References in corpus (36)

• Observations of the Icy Universe
• Complex Chemistry in Star-Forming Regions: An Expanded Gas-Grain Warm-up Chemical Model
• Formation of methyl formate and other organic species in the warm-up phase of hot molecular cores
• A Major Asymmetric Dust Trap in a Transition Disk
• Formation rates of complex organics in UV irradiated CH3OH-rich ices I: Experiments
• Our astrochemical heritage
• Astrochemistry and compositions of planetary systems
• H-atom addition and abstraction reactions in mixed CO, H2CO and CH3OH ices: an extended view on complex organic molecule formation
• First detection of gas-phase methanol in a protoplanetary disk
• The ALMA-PILS survey: Isotopic composition of oxygen-containing complex organic molecules toward IRAS 16293-2422B
• Constraining the abundances of complex organics in the inner regions of solar-type protostars
• The ALMA-PILS survey: Inventory of complex organic molecules towards IRAS 16293-2422 A
• Ingredients for Solar-like Systems: protostar IRAS 16293-2422 B versus comet 67P/Churyumov-Gerasimenko
• The ice composition in the disk around V883 Ori revealed by its stellar outburst
• Questioning the spatial origin of complex organic molecules in young protostars with the CALYPSO survey
• A non-energetic mechanism for glycine formation in the interstellar medium
• A Survey of CH3CN and HC3N in Protoplanetary Disks
• On the diversity of asymmetries in gapped protoplanetary disks
• First Detection of the Simplest Organic Acid in a Protoplanetary Disk
• The negligible photodesorption of methanol ice and the active photon-induced desorption of its irradiation products
• Complex organic molecules in low-mass protostars on solar system scales -- I. Oxygen-bearing species
• The Distribution and Excitation of CH${}_3$CN in a Solar Nebula Analog
• Methanol and its relation to the water snowline in the disk around the young outbursting star V883 Ori
• Evolutionary study of complex organic molecules in high-mass star-forming regions
• Complex organic molecules in low-mass protostars on Solar System scales -- II. Nitrogen-bearing species
• Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC${}_3$N, CH${}_3$CN, and $c$-C${}_3$H${}_2$
• A major asymmetric ice trap in a planet-forming disk: I. Formaldehyde and methanol
• Complex Organic Molecules Towards Embedded Low-Mass Protostars
• Upper limits on CH${}_3$OH in the HD 163296 protoplanetary disk: evidence for a low gas-phase CH${}_3$OH/H${}_2$CO ratio
• Prestellar grain-surface origins of deuterated methanol in comet 67P/Churyumov-Gerasimenko
• Warm formaldehyde in the Oph IRS 48 transitional disk
• Solving grain size inconsistency between ALMA polarization and VLA continuum in the Ophiuchus IRS 48 protoplanetary disk
• Complex organic molecules along the accretion flow in isolated and externally irradiated protoplanetary disks
• H2 chemistry in interstellar ices: the case of CO ice hydrogenation in UV irradiated CO:H2 ice mixtures
• Methanol formation in TW Hya and future prospects for detecting larger complex molecules in disks with ALMA
• Temperature structures of embedded disks: young disks in Taurus are warm

Cited by in corpus (27)

• LIDA - The Leiden Ice Database for Astrochemistry
• Sulphur monoxide emission tracing an embedded planet in the HD 100546 protoplanetary disk
• Transition disks: the observational revolution from SEDs to imaging
• Hunt for complex cyanides in protostellar ices with JWST: Tentative detection of CH${}_3$CN and C${}_2$H${}_5$CN
• CoCCoA: Complex Chemistry in hot Cores with ALMA. Selected oxygen-bearing species
• JOYS+: link between ice and gas of complex organic molecules. Comparing JWST and ALMA data of two low-mass protostars
• SO and SiS Emission Tracing an Embedded Planet and Compact ${}^{12}$CO and ${}^{13}$CO Counterparts in the HD 169142 Disk
• Early Planet Formation in Embedded Disks (eDisk). IV. The Ringed and Warped Structure of the Disk around the Class I Protostar L1489 IRS
• Investigating the asymmetric chemistry in the disk around the young star HD 142527
• Formation of S-bearing complex organic molecules in interstellar clouds via ice reactions with C2H2, HS, and atomic H
• FAUST XVII: Super deuteration in the planet forming system IRS 63 where the streamer strikes the disk
• Shocking Sgr B2(N1) with its own outflow: A new perspective on segregation between O- and N-bearing molecules
• A major asymmetric ice trap in a planet-forming disk IV. Nitric oxide gas and a lack of CN tracing sublimating ices and a C/O ratio $<1$
• A deep search for large complex organic species toward IRAS16293-2422 B at 3 mm with ALMA
• The Molecular Composition of Shadowed Protosolar Disk Midplanes beyond the Water Snowline
• The rapid formation of macromolecules in irradiated ice of protoplanetary disk dust traps
• ALMA reveals thermal and non-thermal desorption of methanol ice in the HD 100546 protoplanetary disk
• Conformational isomerism of methyl formate: new detections of the higher-energy trans conformer and theoretical insights
• Meteorite Parent Body Aqueous Alteration Simulations of Interstellar Residue Analogs
• An SMA Survey of Chemistry in Disks around Herbig AeBe Stars
• A deep search for Complex Organic Molecules toward the protoplanetary disk of V883 Ori
• Complex Organic Molecules Formation in Cold Cores on Stochastically Heated Grains
• A deep Search for Ethylene Glycol and Glycolonitrile in the V883 Ori Protoplanetary Disk
• Post-Outburst Chemistry in a Very Low-Luminosity Object: Peculiar High Abundance of Nitric Oxide
• Observational evidence for a possible link between PAH emission and dust trap locations in protoplanetary disks
• Hunting for methanol in the water rich, planet forming disk around HL Tau
• Protoplanetary Disk Chemistry