An All-sky Catalog of 6.5 Million Primary Red Clump Stars from Gaia DR3 XP Spectra
- 1Chuxiong Normal College
- 2Yunnan University
Abstract
Red clump (RC) stars are excellent standard candles for mapping the three-dimensional structure of the Milky Way. We construct an all-sky catalog of 6.5 million primary RC stars using spectroscopic estimates of asteroseismic parameters inferred from Gaia DR3 low-resolution XP spectra. We train a mixture density network (MDN) on a crossmatched sample. The network maps each 343-dimensional corrected XP spectrum to estimates of ΔΠ ₁ , the asymptotic period spacing of dipole gravity modes, and Δ ν , the large frequency separation. We select primary RC stars using these two estimates. We release two complementary catalogs defined by different parameter-space cuts and thresholds: a high-purity Tier 1 sample of 532,189 stars with 97% purity and a high-completeness Tier 2 sample of 6,534,931 stars with 86% completeness. Both catalogs cover the full celestial sphere. We provide distances and extinction values for all stars. We obtain a median photometric distance precision of 6% for Tier 1 RC stars. Using the resultant distances, we independently calibrate the Gaia DR3 parallax zero-point offset. The three-dimensional density distribution traced by the Tier 2 sample extends continuously to R ≃ 25 kpc. Both catalogs are publicly available. These catalogs provide a valuable resource for Galactic archaeology, delivering a homogeneous dataset to trace the chemodynamical evolution of the Milky Way and to calibrate models of stellar populations.
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BibTeX
@article{yu2026allsky,
title = {{An All-sky Catalog of 6.5 Million Primary Red Clump Stars from Gaia DR3 XP Spectra}},
author = {Zheng Yu and Bingqiu Chen},
journal = {The Astrophysical Journal Supplement Series},
year = {2026},
month = oct,
doi = {10.3847/1538-4365/aea224},
url = {https://iopscience.iop.org/article/10.3847/1538-4365/aea224},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - An All-sky Catalog of 6.5 Million Primary Red Clump Stars from Gaia DR3 XP Spectra
AU - Zheng Yu
AU - Bingqiu Chen
PY - 2026
DA - 2026/10/07
JO - The Astrophysical Journal Supplement Series
DO - 10.3847/1538-4365/aea224
UR - https://iopscience.iop.org/article/10.3847/1538-4365/aea224
AB - Red clump (RC) stars are excellent standard candles for mapping the three-dimensional structure of the Milky Way. We construct an all-sky catalog of 6.5 million primary RC stars using spectroscopic estimates of asteroseismic parameters inferred from Gaia DR3 low-resolution XP spectra. We train a mixture density network (MDN) on a crossmatched sample. The network maps each 343-dimensional corrected XP spectrum to estimates of ΔΠ ₁ , the asymptotic period spacing of dipole gravity modes, and Δ ν , the large frequency separation. We select primary RC stars using these two estimates. We release two complementary catalogs defined by different parameter-space cuts and thresholds: a high-purity Tier 1 sample of 532,189 stars with 97% purity and a high-completeness Tier 2 sample of 6,534,931 stars with 86% completeness. Both catalogs cover the full celestial sphere. We provide distances and extinction values for all stars. We obtain a median photometric distance precision of 6% for Tier 1 RC stars. Using the resultant distances, we independently calibrate the Gaia DR3 parallax zero-point offset. The three-dimensional density distribution traced by the Tier 2 sample extends continuously to R ≃ 25 kpc. Both catalogs are publicly available. These catalogs provide a valuable resource for Galactic archaeology, delivering a homogeneous dataset to trace the chemodynamical evolution of the Milky Way and to calibrate models of stellar populations.
SN - 0067-0049
SN - 1538-4365
ER -