New chondritic bodies identified in eight oxygen-bearing white dwarfs

Abstract

We present observations and analyses of eight white dwarf stars that have accreted rocky material from their surrounding planetary systems. The spectra of these helium-atmosphere white dwarfs contain detectable optical lines of all four major rock-forming elements (O, Mg, Si, Fe). This work increases the sample of oxygen-bearing white dwarfs with parent body composition analyses by roughly thirty-three percent. To first order, the parent bodies that have been accreted by the eight white dwarfs are similar to those of chondritic meteorites in relative elemental abundances and oxidation states. Seventy-five percent of the white dwarfs in this study have observed oxygen excesses implying volatiles in the parent bodies with abundances similar to those of chondritic meteorites. Three white dwarfs have oxidation states that imply more reduced material than found in CI chondrites, indicating the possible detection of Mercury-like parent bodies, but are less constrained. These results contribute to the recurring conclusion that extrasolar rocky bodies closely resemble those in our solar system, and do not, as a whole, yield unusual or unique compositions.

Accepted for publication in ApJ. 7 Figures, 7 Tables

References in corpus (25)

• The Gaia mission
• The frequency of planetary debris around young white dwarfs
• The Structure of the Local Interstellar Medium V: Electron Densities
• The Chemical Composition of an Extrasolar Minor Planet
• On the Spectral Evolution of Cool, Helium-Atmosphere White Dwarfs: Detailed Spectroscopic and Photometric Analysis of DZ Stars
• On the Measurement of Fundamental Parameters of White Dwarfs in the Gaia Era
• Accretion of a giant planet onto a white dwarf
• The Chemical Composition of an Extrasolar Kuiper-Belt-Object
• Oxygen fugacities of extrasolar rocks: Evidence for an Earth-like geochemistry of exoplanets
• Likely detection of water-rich asteroid debris in a metal-polluted white dwarf
• Compositions of Planetary Debris around Dusty White Dwarfs
• Does a Differentiated, Carbonate-Rich, Rocky Object Pollute the White Dwarf SDSSJ104341.53+085558.2?
• Are exoplanetesimals differentiated?
• Recurring Planetary Debris Transits and Circumstellar Gas around White Dwarf ZTF J0328$-$1219
• Alkali metals in white dwarf atmospheres as tracers of ancient planetary crusts
• White dwarf pollution by hydrated planetary remnants: Hydrogen and Metals in WD J204713.76-125908.9
• 3D spectroscopic analysis of helium-line white dwarfs
• Infrared Excesses around Bright White Dwarfs from Gaia and unWISE. II
• Icy Exomoons Evidenced by Spallogenic Nuclides in Polluted White Dwarfs
• GD424 -- a helium-atmosphere white dwarf with a large amount of trace hydrogen in the process of digesting a rocky planetesimal
• Measuring Elemental Abundances of JWST Target Stars for Exoplanet Characterization I. FGK Stars
• Unusual Abundances from Planetary System Material Polluting the White Dwarf G238-44
• A Convective Dredge-Up Model as the Origin of Hydrogen in DBA White Dwarfs
• Systematic uncertainties in the characterisation of helium-dominated metal-polluted white dwarf atmospheres
• Atmospheric Temperature Inversions and He I 5876 Core Profile Structure in White Dwarfs

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• The 40 pc sample of white dwarfs from Gaia
• The spectral evolution of white dwarfs: where do we stand?
• PEWDD: A database of white dwarfs enriched by exo-planetary material
• A Chondritic Solar Neighborhood
• A mineralogical reason why all exoplanets cannot be equally oxidising
• Discovery of magnetically guided metal accretion onto a polluted white dwarf
• A cool, magnetic white dwarf accreting planetary debris
• Discovery of an icy and nitrogen-rich extrasolar planetesimal
• Characterizing planetary material accreted by cool helium atmosphere white dwarfs using an exponentially decaying disc model
• Do White Dwarfs Sample Water-Rich Planetary Material?
• Tracing Planetary Accretion in a 3 Gyr-old Hydrogen-Rich White Dwarf: The Extremely Polluted Atmosphere of LSPM J0207+3331
• The dark and featureless surface of rocky exoplanet LHS 3844 b from JWST mid-infrared spectroscopy
• I Can Do It With A Broken Planetesimal: Characterising the planetary debris in heavily polluted cool white dwarfs