Searching for Massive Remnant Planetary System Hosts with White Dwarf Gaia XP Spectra
Abstract
Remnant planetary systems around massive white dwarfs (MWD > 0.8 M⊙) are intrinsically rare and remain poorly characterized. As the evolutionary endpoints of intermediate-mass B- and A-type stars, these white dwarfs provide valuable constraints on the formation and survival of planetary systems around higher-mass progenitors. In the absence of large, dedicated spectroscopic surveys, extremely-low-resolution Gaia XP spectra provide a powerful means of identifying candidate metal-polluted white dwarfs. We obtained follow-up observations with low-resolution optical spectroscopy (R=500-4000) to search primarily for Ca II H & K absorption in massive, metal-polluted white dwarf candidates selected from Gaia XP spectra to increase the sample of massive remnant planetary system hosts among objects with effective temperatures below ∼15,000 K. We find that Gaia XP spectra recover metal-polluted white dwarfs efficiently, confirming 82±5% recovery of photospheric metals (59 of 72 targets) in high-confidence candidates of our sample (with classifier probability PDZ > 0.65). However, Gaia photometric masses derived from G, GBP, and GRP broad-band photometry are not sufficient to identify the most massive systems, as reliable mass determinations require detailed metal-enriched atmospheric fits. We present a selection of cool white dwarfs confirmed to be both massive and metal polluted, demonstrating that Gaia XP spectra can substantially expand the sample of white dwarf exoplanet hosts. Our search led to the discovery of a new transiting debris system, SDSS J1624+5404, the 21st published system to date and eighth to show periodic transits.
Related
- Rotating models of very massive close binary stars at solar metallicity: Evolution and remnant masses
- Extended gamma-ray emission in the vicinity of the Westerlund 1 massive star cluster and Kes 41 supernova remnant seen by the Fermi Large Area Telescope
- Solar System Surface Technosignatures: Searching for Signs of Artificial Design on Extraterrestrial Terrain
- Nebular Spectra of the Extremely Metal-Poor SN II 2023ufx Over a Year After Explosion: A Massive Progenitor and Unique Circumstellar Environment
- Detailed study of HD 219134: A benchmark K dwarf with a compact planetary system
BibTeX
@misc{rouis2026searching,
title = {{Searching for Massive Remnant Planetary System Hosts with White Dwarf Gaia XP Spectra}},
author = {Lou Baya Ould Rouis and J. J. Hermes and Pierre Bergeron and Simon Blouin and Stefan Arseneau and Tim Cunningham and Joseph A. Guidry and Ciarra Coston},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.22033},
eprint = {2609.22033},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.22033},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Searching for Massive Remnant Planetary System Hosts with White Dwarf Gaia XP Spectra
AU - Lou Baya Ould Rouis
AU - J. J. Hermes
AU - Pierre Bergeron
AU - Simon Blouin
AU - Stefan Arseneau
AU - Tim Cunningham
AU - Joseph A. Guidry
AU - Ciarra Coston
PY - 2026
DA - 2026/09/18
PB - arXiv
DO - 10.48550/arxiv.2609.22033
UR - https://arxiv.org/abs/2609.22033
AB - Remnant planetary systems around massive white dwarfs (M_WD > 0.8 M_⊙) are intrinsically rare and remain poorly characterized. As the evolutionary endpoints of intermediate-mass B- and A-type stars, these white dwarfs provide valuable constraints on the formation and survival of planetary systems around higher-mass progenitors. In the absence of large, dedicated spectroscopic surveys, extremely-low-resolution Gaia XP spectra provide a powerful means of identifying candidate metal-polluted white dwarfs. We obtained follow-up observations with low-resolution optical spectroscopy (R=500-4000) to search primarily for Ca II H & K absorption in massive, metal-polluted white dwarf candidates selected from Gaia XP spectra to increase the sample of massive remnant planetary system hosts among objects with effective temperatures below ∼15,000 K. We find that Gaia XP spectra recover metal-polluted white dwarfs efficiently, confirming 82±5% recovery of photospheric metals (59 of 72 targets) in high-confidence candidates of our sample (with classifier probability P_DZ > 0.65). However, Gaia photometric masses derived from G, G_BP, and G_RP broad-band photometry are not sufficient to identify the most massive systems, as reliable mass determinations require detailed metal-enriched atmospheric fits. We present a selection of cool white dwarfs confirmed to be both massive and metal polluted, demonstrating that Gaia XP spectra can substantially expand the sample of white dwarf exoplanet hosts. Our search led to the discovery of a new transiting debris system, SDSS J1624+5404, the 21st published system to date and eighth to show periodic transits.
ER -