METAL Hubble prog. II. LMC dust-to-gas ratio

DOI

A key component of the baryon cycle in galaxies is the depletion of metals from the gas to the dust phase in the neutral interstellar medium (ISM). The METAL (Metal Evolution, Transport, and Abundance in the Large Magellanic Cloud) program on the Hubble Space Telescope acquired UV spectra toward 32 sight lines in the half-solar metallicity LMC, from which we derive interstellar depletions (gas-phase fractions) of Mg, Si, Fe, Ni, S, Zn, Cr, and Cu. The depletions of different elements are tightly correlated, indicating a common origin. Hydrogen column density is the main driver for depletion variations. Correlations are weaker with volume density, probed by CI fine-structure lines, and distance to the LMC center. The latter correlation results from an east-west variation of the gas-phase metallicity. Gas in the east, compressed side of the LMC encompassing 30 Doradus and the southeast HI over-density is enriched by up to +0.3dex, while gas in the west side is metal deficient by up to -0.5dex. Within the parameter space probed by METAL, no correlation with molecular fraction or radiation-field intensity are found. We confirm the factor of three to four increase in dust-to-metal and dust-to-gas ratios between the diffuse (logN(H)~20cm^-2^) and molecular (logN(H)~22cm^-2^) ISM observed from far-infrared, 21cm, and CO observations. The variations of dust-to-metal and dust-to-gas ratios with column density have important implications for the sub-grid physics of chemical evolution, gas and dust mass estimates throughout cosmic times, and for the chemical enrichment of the Universe measured via spectroscopy of damped Ly{alpha} systems.

Cone search capability for table J/ApJ/910/95/targets (Spectroscopic targets (Table 1) and measurements of the column densities, derived radiation fields, volume densities and electron densities (Table 6))

Identifier
DOI http://doi.org/10.26093/cds/vizier.19100095
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/910/95
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/910/95
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/910/95
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/910/95
Provenance
Creator Roman-Duval J.; Jenkins E.B.; Tchernyshyov K.; Williams B.; Clark C.J.R.,Gordon K.D.; Meixner M.; Hagen L.; Peek J.; Sandstrom K.; Werk J.,Yanchulova Merica-Jones P.
Publisher CDS
Publication Year 2022
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Galactic and extragalactic Astronomy; Interdisciplinary Astronomy; Interstellar medium; Natural Sciences; Observational Astronomy; Physics