Abundances and Depletions of Neutron-Capture Elements in the Interstellar Medium

Abstract

We present an extensive analysis of the gas-phase abundances and depletion behaviors of neutron-capture elements in the interstellar medium (ISM). Column densities (or upper limits to the column densities) of Ga II, Ge II, As II, Kr I, Cd II, Sn II, and Pb II are determined for a sample of 69 sight lines with high- and/or medium-resolution archival spectra obtained with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. An additional 59 sight lines with column density measurements reported in the literature are included in our analysis. Parameters that characterize the depletion trends of the elements are derived according to the methodology developed by Jenkins (2009; arXiv:0905.3173). (In an appendix, we present similar depletion results for the light element B.) The depletion patterns exhibited by Ga and Ge comport with expectations based on the depletion results obtained for many other elements. Arsenic exhibits much less depletion than expected, and its abundance in low-depletion sight lines may even be supersolar. We confirm a previous finding by Jenkins (2009; arXiv:0905.3173) that the depletion of Kr increases as the overall depletion level increases from one sight line to another. Cadmium shows no such evidence of increasing depletion. We find a significant amount of scatter in the gas-phase abundances of Sn and Pb. For Sn, at least, the scatter may be evidence of real intrinsic abundance variations due to s-process enrichment combined with inefficient mixing in the ISM.

arXiv comment73 pages, 23 figures, accepted for publication in the ApJ Supplement

References in corpus (48)

• The chemical composition of the Sun
• Validation of the new Hipparcos reduction
• Multi-messenger Observations of a Binary Neutron Star Merger
• Swope Supernova Survey 2017a (SSS17a), the Optical Counterpart to a Gravitational Wave Source
• Neutron capture in low mass Asymptotic Giant Branch stars: cross sections and abundance signatures
• A Unified Representation of Gas-Phase Element Depletions in the Interstellar Medium
• The Emergence of a Lanthanide-Rich Kilonova Following the Merger of Two Neutron Stars
• The Galactic O-Star Spectroscopic Survey (GOSSS). II. Bright Southern Stars
• The Definitive Abundance of Interstellar Oxygen
• Neutron star mergers versus core-collapse supernovae as dominant r-process sites in the early Galaxy
• Evolution, nucleosynthesis and yields of AGB stars at different metallicities (III): intermediate mass models, revised low mass models and the ph-FRUITY interface
• Galactic Chemical Evolution and solar s-process abundances: dependence on the 13C-pocket structure
• Ultraviolet Survey of CO and H_2 in Diffuse Molecular Clouds: The Reflection of Two Photochemistry Regimes in Abundance Relationships
• The s-Process in Low Metallicity Stars. II. Interpretation of High-Resolution Spectroscopic Observations with AGB models
• The elemental composition of the Sun I. The intermediate mass elements Na to Ca
• s-Process Nucleosynthesis in AGB Stars: A Test for Stellar Evolution
• Dust formation in the oxygen-rich AGB star IK Tau
• The elemental composition of the Sun III. The heavy elements Cu to Th
• The Diffuse Interstellar Clouds toward 23 Orionis
• Condensation of dust in the ejecta of type II-P supernovae
• s-Process Nucleosynthesis in Advanced Burning Phases of Massive Stars
• The Far Ultraviolet Spectroscopic Explorer Survey of OVI Absorption in the Disk of the Milky Way
• The Homogeneity of Interstellar Oxygen in the Galactic Disk
• Nucleosynthesis Predictions for Intermediate-Mass AGB Stars: Comparison to Observations of Type I Planetary Nebulae
• The Homogeneity of Interstellar Elemental Abundances in the Galactic Disk
• Oxygen Gas Phase Abundance Revisited
• PO and PN in the wind of the oxygen-rich AGB star IK Tau
• Depletion patterns and dust evolution in the ISM
• r-process Production Sites as inferred from Eu Abundances in Dwarf Galaxies
• Hubble Space Telescope Survey of Interstellar ^12CO/^13CO in the Solar Neighborhood
• Seed particle formation for silicate dust condensation by SiO nucleation
• New Detections of Arsenic, Selenium, and Other Heavy Elements in Two Metal-Poor Stars
• Further Evidence for Chemical Fractionation from Ultraviolet Observations of Carbon Monoxide
• The Galactic evolution of phosphorus
• Germanium, Arsenic, and Selenium Abundances in Metal-Poor Stars
• Detection of Neutral Phosphorus in the Near Ultraviolet Spectra of Late-Type Stars
• An Ultra-High-Resolution Survey of the Interstellar ^7Li-to-^6Li Isotope Ratio in the Solar Neighborhood
• Discovery of Rubidium, Cadmium, and Germanium Emission Lines in the Near-Infrared Spectra of Planetary Nebulae
• The Abundances of Light Neutron-Capture Elements in Planetary Nebulae III. The Impact of New Atomic Data on Nebular Selenium and Krypton Abundance Determinations
• The Homogeneity of Interstellar Krypton in the Galactic Disk
• Revisiting the Chlorine Abundance in Diffuse Interstellar Clouds from Measurements with the Copernicus Satellite
• Monitoring the Variable Interstellar Absorption toward HD 219188 with HST/STIS
• Interstellar Krypton Abundances: The Detection of Kiloparsec-scale Differences in Galactic Nucleosynthetic History
• The Abundance of Boron in Diffuse Interstellar Clouds
• The Interstellar Rubidium Isotope Ratio toward Rho Ophiuchi A
• Oscillator Strengths for Ultraviolet Transitions in P II
• Lifetimes and Oscillator Strengths for Ultraviolet Transitions in Singly-Ionized Lead
• Rubidium in the Interstellar Medium

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• Dust emissivity and absorption cross section in DustPedia late-type galaxies
• The CARMENES search for exoplanets around M dwarfs: Rubidium abundances in nearby cool stars
• HD 62542: Probing the Bare, Dense Core of a Translucent Interstellar Cloud
• The Distribution of Metallicities in the Local Galactic Interstellar Medium
• A Closer Look at Some Gas-Phase Depletions in the ISM: Trends for O, Ge, and Kr vs. $F_{\ast }$, $f({\mathrm{H}}_2)$, and Starlight Intensity
• A Reexamination of Phosphorus and Chlorine Depletions in the Diffuse Interstellar Medium
• The Transition from Diffuse Molecular Gas to Molecular Cloud Material in Taurus
• Rubidium abundances in solar metallicity stars
• Laboratory astrophysics: key to understanding the Universe
• A Definitive Determination of the Interstellar Carbon Abundance toward rho Ophiuchi A and B