A new study of an old sink of sulfur in hot molecular cores: the sulfur residue

Abstract

Sulfur appears to be depleted by an order of magnitude or more from its elemental abundance in star-forming regions. In the last few years, numerous observations and experiments have been performed in order to to understand the reasons behind this depletion without providing a satisfactory explanation of the sulfur chemistry towards high-mass star-forming cores. Several sulfur-bearing molecules have been observed in these regions, and yet none are abundant enough to make up the gas-phase deficit. Where, then, does this hidden sulfur reside? This paper represents a step forward in our understanding of the interactions among the various S-bearing species. We have incorporated recent experimental and theoretical data into a chemical model of a hot molecular core in order to see whether they give any indication of the identity of the sulfur sink in these dense regions. Despite our model producing reasonable agreement with both solid-phase and gas-phase abundances of many sulfur-bearing species, we find that the sulfur residue detected in recent experiments takes up only ~6 per cent of the available sulfur in our simulations, rather than dominating the sulfur budget.

arXiv comment13 pages, 6 colourful figures, accepted by MNRAS

References in corpus (27)

• A Unified Representation of Gas-Phase Element Depletions in the Interstellar Medium
• A KInetic Database for Astrochemistry (KIDA)
• Evaporation of ices near massive stars: models based on laboratory TPD data
• Does IRAS 16293-2422 have a hot core? Chemical inventory and abundance changes in its protostellar environment
• Resetting chemical clocks of hot cores based on S-bearing molecules
• Sulfur depletion in dense clouds and circumstellar regions I. H2S ice abundance and UV-photochemical reactions in the H2O-matrix
• Chemical evolution in the early phases of massive star formation. I
• Sulphur chemistry in the envelopes of massive young stars
• Desorption From Interstellar Ices
• ISO spectroscopy of compact HII regions in the Galaxy. II Ionization and elemental abundances
• Spectroscopic characterization and detection of Ethyl Mercaptan in Orion
• Spitzer IRS Observations of Class I/II Objects in Taurus: Composition and Thermal History of the Circumstellar Ices
• Submillimeter absorption from SH+, a new widespread interstellar radical, 13CH+ and HCl
• Faint emission lines in the Galactic H II regions M16, M20 and NGC 3603
• Discovery of interstellar mercapto radicals (SH) with the GREAT instrument on SOFIA
• Molecular abundances in carbon-rich circumstellar envelopes
• Interferometric imaging of the sulfur-bearing molecules H2S, SO and CS in comet C/1995 O1 (Hale-Bopp)
• Molecular line survey of the high-mass star-forming region NGC 6334I with Herschel/HIFI and the SMA
• A Method for Deriving Accurate Gas-Phase Abundances for the Multiphase Interstellar Galactic Halo
• S-bearing molecules in Massive Dense Cores
• Sulfur chemistry: 1D modeling in massive dense cores
• Polysulfanes on interstellar grains as a possible reservoir of interstellar sulphur
• Review of OCS gas-phase reactions in dark cloud chemical models
• A study of methyl formate in astrochemical environments
• Modelling of c-C2H4O formation on grain surfaces
• First evidence for molecular interfaces between outflows and ambient cloud in high-mass star forming regions?
• Kinematics and chemistry of the hot core in G20.08-0.14N

Cited by in corpus (37)

• On the reservoir of sulphur in dark clouds : chemistry and elemental abundance reconciled
• Modeling Sulfur Depletion in Interstellar Clouds
• Cometary Chemistry and the Origin of Icy Solar System Bodies, the view after Rosetta
• Abundant refractory sulfur in protoplanetary disks
• The ALMA-PILS survey: The sulphur connection between protostars and comets: IRAS 16293-2422 B and 67P/Churyumov-Gerasimenko
• An infrared measurement of chemical desorption from interstellar ice analogues
• Detection of CH3SH in protostar IRAS 16293-2422
• Photoprocessing of H2S on dust grains: building S chains in translucent clouds and comets
• A new look at sulphur chemistry in hot cores and corinos
• Sulfur Ice Astrochemistry: A Review of Laboratory Studies
• The sulfur depletion problem: upper limits on the H2S2, HS2, and S2 gas-phase abundances toward the low-mass warm core IRAS16293-2422
• H2S in the L1157-B1 Bow shock
• Search for Interstellar monohydric Thiols
• ExoMol molecular line lists - XXVI: spectra of SH and NS
• Ammonium hydrosulfide (NH4SH) as a potentially significant sulfur sink in interstellar ices
• Tunneling Reaction Kinetics for the Hydrogen Abstraction Reaction H + H${}_2$S -> H${}_2$ + HS in the Interstellar Medium
• Thermal and energetic processing of astrophysical ice analogues rich in SO${}_2$
• Rovibrationally-Resolved Photodissociaton of SH${}^{+}$
• Physical properties of accretion shocks toward the Class I protostellar system Oph-IRS 44
• The mid-infrared molecular inventory towards Orion IRc2
• High-Resolution SOFIA/EXES Spectroscopy of ${\mathrm{SO}}_2$ Gas in the Massive Young Stellar Object MonR2 IRS3: Implications for the Sulfur Budget
• Complex molecules in W51 North region
• ALMA observations of CS in NGC 1068: chemistry and excitation
• Accurate millimetre and submillimetre rest frequencies for $cis$- and $trans$-dithioformic acid, HCSSH
• Theoretical modelling of the adsorption of neutral and charged sulphur-bearing species on to olivine nanoclusters
• First Identification and Chemical Modeling of New Thiol ($-$SH) Bearing Molecule in the Interstellar Medium: Dithioformic Acid
• SO2 and OCS toward high-mass protostars: A comparative study between ice and gas
• ALMA ACA study of the H${}_2$S/OCS ratio in low-mass protostars
• An ALCHEMI inspection of sulphur-bearing species towards the central molecular zone of NGC 253
• Exploiting Network Topology for Accelerated Bayesian Inference of Grain Surface Reaction Networks
• Sulfur-bearing molecules in a sample of early star-forming cores
• APEX and NOEMA observations of H${}_2$S in nearby luminous galaxies and the ULIRG Mrk~231 -- Is there a relation between dense gas properties and molecular outflows?
• XRISM insights for interstellar Sulfur
• A major asymmetric ice trap in a planet-forming disk: II. prominent SO and SO2 pointing to C/O < 1
• Identifying the most constraining ice observations to infer molecular binding energies
• JOYS: Linking the molecular ice and gas-phase composition towards the high-mass hot core IRAS 18089-1732
• High resolution ALMA observations of H${}_2$S in LIRGS (Dense gas and shocks in outflows and CNDs)