Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3
White dwarf (WD) stars evolve simply and predictably, making them reliable age indicators. However, self-consistent validation of the methods for determining WD total ages has yet to be widely performed. This work uses 1565 wide (>100 au) WD+WD binaries and 24 new triples containing at least two...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2022-01-01
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| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/ac78d9 |
| _version_ | 1797682192233529344 |
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| author | Tyler M. Heintz J. J. Hermes Kareem El-Badry Charlie Walsh Jennifer L. van Saders C. E. Fields Detlev Koester |
| author_facet | Tyler M. Heintz J. J. Hermes Kareem El-Badry Charlie Walsh Jennifer L. van Saders C. E. Fields Detlev Koester |
| author_sort | Tyler M. Heintz |
| collection | DOAJ |
| description | White dwarf (WD) stars evolve simply and predictably, making them reliable age indicators. However, self-consistent validation of the methods for determining WD total ages has yet to be widely performed. This work uses 1565 wide (>100 au) WD+WD binaries and 24 new triples containing at least two WDs to test the accuracy and validity of WD total age determinations. For these 1589 wide double WD binaries and triples, we derive the total age of each WD using photometric data from all-sky surveys, in conjunction with Gaia parallaxes and current hydrogen atmosphere WD models. Ignoring the initial-to-final mass relation and considering only WD cooling ages, we find that roughly 21%–36% of the more massive WDs in a system have a shorter cooling age. Since more massive WDs should be born as more massive main-sequence stars, we interpret this unphysical disagreement as evidence of prior mergers or the presence of an unresolved companion, suggesting that roughly 21%–36% of wide WD+WD binaries were once triples. Among the 423 wide WD+WD pairs that pass high-fidelity cuts, we find that 25% total age uncertainties are generally appropriate for WDs with masses >0.63 M _⊙ and temperatures <12,000 K and provide suggested inflation factors for age uncertainties for higher-mass WDs. Overall, WDs return reliable stellar ages, but we detail cases where the total ages are least reliable, especially for WDs <0.63 M _⊙ . |
| first_indexed | 2024-03-11T23:55:59Z |
| format | Article |
| id | doaj.art-667ee6f92e9a428ca44e0e84622777c4 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-11T23:55:59Z |
| publishDate | 2022-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-667ee6f92e9a428ca44e0e84622777c42023-09-18T11:17:10ZengIOP PublishingThe Astrophysical Journal1538-43572022-01-01934214810.3847/1538-4357/ac78d9Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3Tyler M. Heintz0https://orcid.org/0000-0003-3868-1123J. J. Hermes1https://orcid.org/0000-0001-5941-2286Kareem El-Badry2https://orcid.org/0000-0002-6871-1752Charlie Walsh3Jennifer L. van Saders4https://orcid.org/0000-0002-4284-8638C. E. Fields5https://orcid.org/0000-0002-8925-057XDetlev Koester6https://orcid.org/0000-0002-6164-6978Department of Astronomy & Institute for Astrophysical Research, Boston University , 725 Commonwealth Avenue, Boston, MA 02215, USA ; tmheintz@bu.eduDepartment of Astronomy & Institute for Astrophysical Research, Boston University , 725 Commonwealth Avenue, Boston, MA 02215, USA ; tmheintz@bu.eduCenter for Astrophysics ∣Harvard & Smithsonian , 60 Garden Street, Cambridge, MA 02138, USA; Harvard Society of Fellows, 78 Mount Auburn Street, Cambridge, MA 02138, USADepartment of Astronomy & Institute for Astrophysical Research, Boston University , 725 Commonwealth Avenue, Boston, MA 02215, USA ; tmheintz@bu.eduInstitute for Astronomy, University of Hawai’i , 2680 Woodlawn Drive, Honolulu, HI 96822, USACenter for Theoretical Astrophysics , Los Alamos National Laboratory, Los Alamos, NM 87545, USA; Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USA; X Computational Physics Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USAInstitut für Theoretische Physik und Astrophysik, University of Kiel , D-24098 Kiel, GermanyWhite dwarf (WD) stars evolve simply and predictably, making them reliable age indicators. However, self-consistent validation of the methods for determining WD total ages has yet to be widely performed. This work uses 1565 wide (>100 au) WD+WD binaries and 24 new triples containing at least two WDs to test the accuracy and validity of WD total age determinations. For these 1589 wide double WD binaries and triples, we derive the total age of each WD using photometric data from all-sky surveys, in conjunction with Gaia parallaxes and current hydrogen atmosphere WD models. Ignoring the initial-to-final mass relation and considering only WD cooling ages, we find that roughly 21%–36% of the more massive WDs in a system have a shorter cooling age. Since more massive WDs should be born as more massive main-sequence stars, we interpret this unphysical disagreement as evidence of prior mergers or the presence of an unresolved companion, suggesting that roughly 21%–36% of wide WD+WD binaries were once triples. Among the 423 wide WD+WD pairs that pass high-fidelity cuts, we find that 25% total age uncertainties are generally appropriate for WDs with masses >0.63 M _⊙ and temperatures <12,000 K and provide suggested inflation factors for age uncertainties for higher-mass WDs. Overall, WDs return reliable stellar ages, but we detail cases where the total ages are least reliable, especially for WDs <0.63 M _⊙ .https://doi.org/10.3847/1538-4357/ac78d9White dwarf starsWide binary starsStellar ages |
| spellingShingle | Tyler M. Heintz J. J. Hermes Kareem El-Badry Charlie Walsh Jennifer L. van Saders C. E. Fields Detlev Koester Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3 The Astrophysical Journal White dwarf stars Wide binary stars Stellar ages |
| title | Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3 |
| title_full | Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3 |
| title_fullStr | Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3 |
| title_full_unstemmed | Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3 |
| title_short | Testing White Dwarf Age Estimates Using Wide Double White Dwarf Binaries from Gaia EDR3 |
| title_sort | testing white dwarf age estimates using wide double white dwarf binaries from gaia edr3 |
| topic | White dwarf stars Wide binary stars Stellar ages |
| url | https://doi.org/10.3847/1538-4357/ac78d9 |
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