New extended deuterium fractionation model: assessment at dense ISM conditions and sensitivity analysis

Abstract

Observations of deuterated species are useful in probing the temperature, ionization level, evolutionary stage, chemistry, and thermal history of astrophysical environments. The analysis of data from ALMA and other new telescopes requires an elaborate model of deuterium fractionation. This paper presents a publicly available chemical network with multi-deuterated species and an extended, up-to-date set of gas-phase and surface reactions. To test this network, we simulate deuterium fractionation in diverse interstellar sources. Two cases of initial abundances are considered: i) atomic except for H2 and HD, and ii) molecular from a prestellar core. We reproduce the observed D/H ratios of many deuterated molecules, and sort the species according to their sensitivity to temperature gradients and initial abundances. We find that many multiply-deuterated species produced at 10 K retain enhanced D/H ratios at temperatures $\la 100$ K. We study how recent updates to reaction rates affect calculated D/H ratios, and perform a detailed sensitivity analysis of the uncertainties of the gas-phase reaction rates in the network. We find that uncertainties are generally lower in dark cloud environments than in warm IRDCs and that uncertainties increase with the size of the molecule and number of D-atoms. A set of the most problematic reactions is presented. We list potentially observable deuterated species predicted to be abundant in low- and high-mass star-formation regions.

30 pages, 8 figures, accepted for publication in ApJS

References in corpus (100)

• A computer program for fast non-LTE analysis of interstellar line spectra
• Cold Dark Clouds: The Initial Conditions for Star Formation
• 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
• Structure of Stationary Photodissociation Fronts
• Formation rates of complex organics in UV irradiated CH3OH-rich ices I: Experiments
• Non-thermal desorption from interstellar dust grains via exothermic surface reactions
• Probing the evolutionary status of starless cores through N2H+ and N2D+ observations
• Molecular Hydrogen Formation on Astrophysically Relevant Surfaces
• Photodesorption of ices I: CO, N2 and CO2
• Reactive Desorption and Radiative Association as Possible Drivers of Complex Molecule Formation in the Cold Interstellar Medium
• On the Formation of CO2 and Other Interstellar Ices
• First detection of triply-deuterated methanol
• Molecular Evolution and Star Formation: From Prestellar Cores to Protostellar Cores
• Complete Depletion in prestellar cores
• Detection of doubly-deuterated methanol in the solar-type protostar IRAS16293-2422
• Chemistry in Disks. IV. Benchmarking gas-grain chemical models with surface reactions
• Abundant H2D+ in the pre-stellar core L1544
• Master Equation for Hydrogen Recombination on Grain Surfaces
• CO Depletion and Deuterium Fractionation in Prestellar Cores
• Chemical modeling of L183 (= L134N) : an estimate of the ortho/para H2 ratio
• The importance of the ortho:para H2 ratio for the deuteration of molecules during pre-protostellar collapse
• Testing grain surface chemistry : a survey of deuterated formaldehyde and methanol in low-mass Class 0 protostars
• The Degree of CO Depletion in Pre-stellar Cores
• The earliest phases of star formation - A Herschel key project. The thermal structure of low-mass molecular cloud cores
• Survey of ortho-H2D+(1_{1,0}-1_{1,1}) in dense cloud cores
• The N2D+/N2H+ ratio as an evolutionary tracer of Class 0 protostars
• Microscopic simulation of methanol and formaldehyde ice formation in cold dense cores
• A Unified Monte Carlo Treatment of Gas-Grain Chemistry for Large Reaction Networks. II. A Multiphase Gas-Surface-Layered Bulk Model
• A study of deuterated water in the low-mass protostar IRAS16293-2422
• Triply deuterated ammonia in NGC 1333
• From Prestellar to Protostellar Cores II. Time Dependence and Deuterium Fractionation
• Interstellar deuterated ammonia: From NH3 to ND3
• Detection of D2H+ in the Dense Interstellar Medium
• Resolving the chemistry in the disk of TW Hydrae I. Deuterated species
• Molecular Evolution in Collapsing Prestellar Cores II: The Effect of Grain-surface Reactions
• Probing the Early Stages of Low-Mass Star Formation in LDN 1689N: Dust and Water in IRAS 16293-2422A, B, and E
• Observations of L1521F: a highly evolved starless core
• H-D Substitution in Interstellar Solid Methanol: A Key Route for D Enrichment
• The Earliest Phases of Star formation observed with Herschel (EPoS): The dust temperature and density distributions of B68
• The chemistry of multiply deuterated molecules in protoplanetary disks. I. The outer disk
• Cosmic-ray and X-ray Heating of Interstellar Clouds and Protoplanetary Disks
• Detection of interstellar H_2D^+ emission
• Two-dimensional Distributions and Column Densities of Gaseous Molecules in Protoplanetary Disks II
• On the robustness of the ammonia thermometer
• Formaldehyde and methanol deuteration in protostars: fossiles from a past fast high density pre-collapse phase
• The Distribution of Ortho-H_2D+(1_1,0 - 1_1,1) in L1544: Tracing the Deuteration Factory in Prestellar Cores
• Chemistry in Protoplanetary Disks: A Sensitivity Analysis
• Searching for massive pre--stellar cores through observations of N2H+ and N2D+
• Deuterated Thioformaldehyde in the Barnard 1 Cloud
• HDO abundance in the envelope of the solar-type protostar IRAS16293-2422
• Deuterium chemistry in the Orion Bar PDR - "warm" chemistry starring CH2D+
• Interferometric multi-wavelength (sub)millimeter continuum study of the young high-mass protocluster IRAS05358+3543
• SMA observations of Infrared Dark Clouds: A tale of two cores
• Detection of DCO+ in a circumstellar disk
• Interstellar ices as witnesses of star formation: selective deuteration of water and organic molecules unveiled
• The ionization fraction gradient across the Horsehead edge: An archetype for molecular clouds
• The evolutionary state of the southern dense core Cha-MMS1
• Sensitivity analyses of dense cloud chemical models
• HD depletion in starless cores
• Search for solid HDO in low-mass protostars
• Looking into the hearts of Bok globules: MM and submm continuum images of isolated star-forming cores
• Deuterated Ammonia in Galactic Protostellar Cores
• Deuterated formaldehyde in rho Ophiuchi A
• Observing a column-dependent zeta in dense interstellar sources: the case of the Horsehead Nebula
• Deuterated molecules in DM Tau: DCO+, but no HDO
• Deuterated H${}_3^{+}$ in proto-planetary disks
• Physical properties of Southern infrared dark clouds
• The NH2D/NH3 ratio toward pre-protostellar cores around the UCHII region in IRAS 20293+3952
• Water deuterium fractionation in the low-mass protostar NGC1333-IRAS2A
• Hyperfine structure in the J = 1-0 transitions of DCO+, DNC, and HN13C: astronomical observations and quantum-chemical calculations
• Modelling line emission of deuterated H_3^+ from prestellar cores
• Polysulfanes on interstellar grains as a possible reservoir of interstellar sulphur
• Extended emission of D2H+ in a prestellar core
• Deuterated molecular hydrogen in the Galactic ISM. New observations along seven translucent sightlines
• First detection of ND in the solar-mass protostar IRAS16293-2422
• Millimeter interferometry of W3 IRS5: A Trapezium in the making
• The HDO/H2O ratio in gas in the inner regions of a low-mass protostar
• Evidence for Multiple Pathways to Deuterium Enhancements in Protoplanetary Disks
• Comet C/2004 Q2 (MACHHOLZ): Parent Volatiles, a Search for Deuterated Methane, and Constraint on the CH4 Spin Temperature
• Deuterium Fractionation as an Evolutionary Probe in the Infrared Dark Cloud G28.34+0.06
• A (sub)millimetre study of dense cores in Orion B9
• High NH2D/NH3 ratios in protostellar cores
• The Initial Conditions of Clustered Star Formation III. The Deuterium Fractionation of the Ophiuchus B2 Core
• Mapping Observations of DNC and HN^13C in Dark Cloud Cores
• Chemical sensitivity to the ratio of the cosmic-ray ionization rates of He and H2 in dense clouds
• A New FUSE Survey of Interstellar HD
• Chemical study of intermediate-mass (IM) Class 0 protostars. CO depletion and N2H+ deuteration
• Chemical modeling of Infrared Dark Clouds: the Role of Surface Chemistry
• Highly deuterated pre-stellar cores in a high-mass star formation region
• Detection of OD towards the low-mass protostar IRAS16293-2422
• Molecular Hydrogen Formation on Porous Dust Grains
• Prestellar and protostellar cores in Ori B9
• TIMASSS : The IRAS16293-2422 Millimeter And Submillimeter Spectral Survey: Tentative Detection of Deuterated Methyl Formate (DCOOCH3)
• The Formation and Evolution of Prestellar Cores
• A deep search for H2D+ in protoplanetary disks
• Statistical universal branching ratios for cosmic ray dissociation, photodissociation, and dissociative recombination of the C(n=2-10), C(n=2-4)H and C3H2 neutral and cationic species
• Upper limit for the D2H+ ortho-to-para ratio in the prestellar core 16293E (CHESS)
• Deuterated species in extragalactic star-forming regions
• Using H3+ and H2D+ as probes of star-forming regions

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• Formation of different isotopomers of chloronium in the interstellar medium
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• Parsec-scale cosmic-ray ionisation rate in Orion
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• Using HCO${}^{+}$ isotopologues as tracers of gas depletion in protoplanetary disk gaps
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• Deuterium chemistry and D/H ratios in Class 0/I proto-brown dwarfs
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• First CH${}_3$D detection in Class 0/I proto-brown dwarfs: constraints on CH${}_4$ abundances
• A survey of HDCO and D${}_2$CO towards Class 0/I proto-brown dwarfs
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• Gas phase Elemental abundances in Molecular cloudS (GEMS). IX. Deuterated compounds of H2S in starless cores
• Gas-phase Elemental abundances in Molecular cloudS (GEMS) XI. The evolution of HCN, HNC, and N2H+ isotopic ratios in starless cores
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