Gas phase Elemental abundances in Molecular cloudS (GEMS). IX. Deuterated compounds of H2S in starless cores

Abstract

H2S is thought to be the main sulphur reservoir in the ice, being therefore a key molecule to understand sulphur chemistry in the star formation process and to solve the missing sulphur problem. The H2S deuterium fraction can be used to constrain its formation pathways. We investigate for the first time the H2S deuteration in a large sample of starless cores (SC). We use observations of the GEMS IRAM 30m Large Program and complementary IRAM 30m observations. We consider a sample of 19 SC in Taurus, Perseus, and Orion, detecting HDS in 10 and D2S in five. The H2S single and double deuterium fractions are analysed with regard to their relation with the cloud physical parameters, their comparison with other interstellar sources, and their comparison with deuterium fractions in early stage star-forming sources of c-C3H2, H2CS, H2O, H2CO, and CH3OH. We obtain a range of X(HDS)/X(H2S)~0.025-0.2 and X(D2S)/X(HDS)~0.05-0.3. H2S single deuteration shows an inverse relation with the cloud kinetic temperature. H2S deuteration values in SC are similar to those observed in Class 0. Comparison with other molecules in other sources reveals a general trend of decreasing deuteration with increasing temperature. In SC and Class 0 objects H2CS and H2CO present higher deuteration fractions than c-C3H2, H2S, H2O, and CH3OH. H2O shows single and double deuteration values one order of magnitude lower than those of H2S and CH3OH. Differences between c-C3H2, H2CS and H2CO deuterium fractions and those of H2S, H2O, and CH3OH are related to deuteration processes produced in gas or solid phases, respectively. We interpret the differences between H2S and CH3OH deuterations and that of H2O as a consequence of differences on the formation routes in the solid phase, particularly in terms of the different occurrence of the D-H and H-D substitution reactions in the ice, together with the chemical desorption processes.

arXiv commentAccepted for publication in A&A

References in corpus (109)

• A computer program for fast non-LTE analysis of interstellar line spectra
• From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey
• A Census of the Young Cluster IC 348
• Herschel view of the Taurus B211/3 filament and striations: Evidence of filamentary growth?
• Our astrochemical heritage
• Non-thermal desorption from interstellar dust grains via exothermic surface reactions
• Large-Scale Structure of the Molecular Gas in Taurus Revealed by High Linear Dynamic Range Spectral Line Mapping
• Cores, filaments, and bundles: hierarchical core formation in the L1495/B213 Taurus region
• Molecular ions in L1544. II. The ionization degree
• Water, O2 and Ice in Molecular Clouds
• N2H+ and C18O Depletion in a Cold Dark Cloud
• Chemistry of Dark Clouds: Databases, Networks, and Models
• Observing the gas temperature drop in the high-density nucleus of L 1544
• The ancient heritage of water ice in the solar system
• The relation between gas and dust in the Taurus Molecular Cloud
• A Large Catalog of Accurate Distances to Local Molecular Clouds: The Gaia DR2 Edition
• First detection of triply-deuterated methanol
• The Properties of Massive, Dense, Clumps: Mapping Surveys of HCN and CS
• Detection of doubly-deuterated methanol in the solar-type protostar IRAS16293-2422
• Formation of Complex Molecules in Prestellar Cores: a Multilayer Approach
• A Compendium of Distances to Molecular Clouds in the Star Formation Handbook
• On the reservoir of sulphur in dark clouds : chemistry and elemental abundance reconciled
• The ALMA-PILS survey: Isotopic composition of oxygen-containing complex organic molecules toward IRAS 16293-2422B
• The anatomy of the Orion B Giant Molecular Cloud: A local template for studies of nearby galaxies
• A CS J=5-4 Mapping Survey Towards High-mass Star Forming Cores Associated with Water Masers
• On the internal structure of starless cores. II. A molecular survey of L1498 and L1517B
• Exploring Molecular Complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)
• CO Depletion and Deuterium Fractionation in Prestellar Cores
• Water in star-forming regions (WISH): Physics and chemistry from clouds to disks as probed by Herschel spectroscopy
• Testing grain surface chemistry : a survey of deuterated formaldehyde and methanol in low-mass Class 0 protostars
• Multilayer modeling of porous grain surface chemistry I. The GRAINOBLE model
• The N2D+/N2H+ ratio as an evolutionary tracer of Class 0 protostars
• The ALMA-PILS survey: Inventory of complex organic molecules towards IRAS 16293-2422 A
• A study of deuterated water in the low-mass protostar IRAS16293-2422
• Sulfur depletion in dense clouds and circumstellar regions I. H2S ice abundance and UV-photochemical reactions in the H2O-matrix
• Protostellar Disk Formation Enabled by Removal of Small Dust Grains
• Isotopic fractionation of carbon, deuterium and nitrogen : a full chemical study
• Gas phase Elemental abundances in Molecular cloudS (GEMS) I. The prototypical dark cloud TMC 1
• A New Reference Chemical Composition for TMC-1
• The ALMA-PILS survey: The sulphur connection between protostars and comets: IRAS 16293-2422 B and 67P/Churyumov-Gerasimenko
• The Five College Radio Astronomy Observatory CO Mapping Survey of the Taurus Molecular Cloud
• CARMA observations of protostellar outflows in NGC 1333
• First detection of doubly deuterated hydrogen sulfide
• Atomic Deuterium/Hydrogen in the Galaxy
• Sulphur-bearing molecules in diffuse molecular clouds: new results from SOFIA/GREAT and the IRAM 30 m telescope
• Water Formation through a Quantum Tunneling Surface Reaction, OH + H2, at 10 K
• Cosmic-ray ionisation in collapsing clouds
• Dense Gas Tracers and Star Formation Laws in Active Galaxies: APEX Survey of HCN J=4-3, HCO+ J=4-3, and CS J=7-6
• Photon-Dominated Chemistry in the Nucleus of M82: Widespread HOC+ emission in the inner 650 pc disk
• Sulphur-bearing species in the star forming region L1689N
• New extended deuterium fractionation model: assessment at dense ISM conditions and sensitivity analysis
• Water ice deuteration: a tracer of the chemical history of protostars
• Benchmarking spin-state chemistry in starless core models
• Large Area Mapping at 850 Microns. V. Analysis of the Clump Distribution in the Orion A South Molecular Cloud
• Nitrogen hydrides and the H2 ortho-to-para ratio in dark clouds
• The deuterium fractionation of water on solar-system scales in deeply-embedded low-mass protostars
• Deuterated Thioformaldehyde in the Barnard 1 Cloud
• Gas phase Elemental abundances in Molecular cloudS (GEMS). II. On the quest for the sulphur reservoir in molecular clouds: the $H_{2}S$ case
• Deuterium chemistry in the Orion Bar PDR - "warm" chemistry starring CH2D+
• Profiling filaments: comparing near-infrared extinction and submillimetre data in TMC-1
• First detection of interstellar S2H
• Star formation in the Taurus filament L1495: From Dense Cores to Stars
• Low Mass Stars and Substellar Objects in the NGC 1333 Molecular Cloud
• Interstellar ices as witnesses of star formation: selective deuteration of water and organic molecules unveiled
• Herschel-Planck dust optical depth and column density maps - II. Perseus
• The ALMA-PILS survey: Formaldehyde deuteration in warm gas on small scales toward IRAS 16293-2422 B
• Modelling the sulphur chemistry evolution in Orion KL
• Ionization fraction and the enhanced sulfur chemistry in Barnard 1
• Warm water deuterium fractionation in IRAS 16293-2422 - The high-resolution ALMA and SMA view
• Nascent bipolar outflows associated with the first hydrostatic core candidates Barnard 1b-N and 1b-S
• The Distances to Molecular Clouds at High Galactic Latitudes based on GAIA DR2
• Water deuterium fractionation in the low-mass protostar NGC1333-IRAS2A
• Abundances of sulphur molecules in the Horsehead nebula. First NS+ detection in a photodissociation region
• Mapping deuterated methanol toward L1544: I. Deuterium fraction and comparison with modeling
• ALMA observations of the young protostellar system Barnard 1b: signatures of an incipient hot corino in B1b-S
• Gas phase Elemental abundances in Molecular cloudS (GEMS). IV. Observational results and statistical trends
• CH2D+, the Search for the Holy Grail
• Decrease of the organic deuteration during the evolution of Sun-like protostars: the case of SVS13-A
• Herschel observations of Extra-Ordinary Sources: H2S as a Probe of Dense Gas and Possibly Hidden Luminosity Toward the Orion KL Hot Core
• The ALMA-PILS survey: The first detection of doubly-deuterated methyl formate (CHD2OCHO) in the ISM
• Structure Function Scaling of a 2MASS Extinction Map of Taurus
• High D${}_2$O/HDO ratio in the inner regions of the low-mass protostar NGC1333 IRAS2A
• Low levels of methanol deuteration in the high-mass star-forming region NGC 6334I
• N2H+ Observations of Molecular Cloud Cores in Taurus
• ALMA observations of water deuteration: A physical diagnostic of the formation of protostars
• Hydrodynamics with gas-grain chemistry and radiative transfer: comparing dynamical and static models
• Deuterated methanol on Solar System scale around the HH212 protostar
• ALMA observations of doubly deuterated water: Inheritance of water from the prestellar environment
• Interferometric observations of warm deuterated methanol in the inner regions of low-mass protostars
• Kinematics of dense gas in the L1495 filament
• Water deuterium fractionation in the inner regions of two solar type protostars
• An unbiased spectral line survey observation toward the low-mass star-forming region L1527
• A Survey of CH2DOH Towards Starless and Prestellar Cores in the Taurus Molecular Cloud
• Evidence for disks at an early stage in class 0 protostars?
• A study of the $c$-${\mathrm{C}}_3\mathrm{HD}$/$c$-${\mathrm{C}}_3{\mathrm{H}}_2$ ratio in low-mass star forming regions
• Successive deuteration in low-mass star-forming regions: the case of D${}_2$-methanol (CHD${}_2$OH) in IRAS 16293-2422
• Sulphur-rich cold gas around the hot core precursor G328.2551-0.5321. An APEX unbiased spectral survey of the 2 mm, 1.2 mm, and 0.8 mm atmospheric windows
• Methanol Mapping in Cold Cores: Testing Model Predictions
• Chemical Differentiation toward the Pipe Nebula Starless Cores
• H2CS deuteration maps towards the pre-stellar core L1544
• Gas phase Elemental abundances in Molecular cloudS (GEMS) VI. A sulphur journey across star-forming regions: study of thioformaldehyde emission
• First detection of NHD and ND${}_2$ in the interstellar medium
• Radial velocities of early-type stars in the Perseus OB2 association
• H${}_2$S observations in young stellar disks in Taurus
• Deuteration of c-C${}_3$H${}_2$ towards the pre-stellar core L1544
• ALMA observations of CS in NGC 1068: chemistry and excitation
• CS Depletion in Prestellar Cores
• Gas vs. solid phase deuterated chemistry: HDCO and D${}_2$CO in massive star-forming regions
• Deuterium fractionation of nitrogen hydrides: detections of NHD and ND${}_2$

Cited by in corpus (2)

• Gas-phase Elemental abundances in Molecular cloudS (GEMS) XI. The evolution of HCN, HNC, and N2H+ isotopic ratios in starless cores
• c-C3H2 deuteration towards prestellar and starless cores in the Perseus Molecular Cloud