Abstract
Gravitational waves (GWs) from compact binary coalescences are standard sirens that provide a direct measure of the source's luminosity distance, enabling an independent measurement of the Hubble constant (H0). While a bright siren—a GW event with an identified electromagnetic (EM) counterpart—provided the first such constraint, most detections, currently dominated by black hole mergers, lack EM signatures. A measurement of H0 is still possible with these dark sirens by statistically associating GW events with galaxies in existing catalogs based on the sky localization. In this work, we explore the potential of two subsets of dark sirens categorized by their localization precision: 'golden' dark sirens, defined by a sky area localization ≤0.1deg2, and 'silver' dark sirens, which are more common but less precisely localized (≤1deg2). Using the fifth internal data release of the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX), we assess the suitability of the Visible Integral-field Replicable Unit Spectrograph (VIRUS) for spectroscopic follow-up of dark sirens. VIRUS exposures of the standard HETDEX depth provide precise redshifts and exquisite completeness within z = 0.2. After a single year of observations with the upgraded LIGO-A# network, the combined sample of golden and silver dark sirens with z ≤ 0.2 at H0 = 70 km s−1 Mpc−1 and follow-up VIRUS observations can potentially yield a few-percent constraint on H0. Our predictions suggest that spectroscopic redshift surveys such as HETDEX can play a key role in realizing high-precision cosmology with dark sirens in the near future.
Recommended Citation
Y. Dang and I. Gupta and R. Ciardullo and E. Mentuch Cooper and S. Pandey and D. Davis and S. More and R. Gray and H. Y. Chen and D. J. Farrow and C. Gronwall and D. Jeong and S. Saito and D. P. Schneider, "Golden and Silver Dark Sirens for Precise H0 Measurement with HETDEX," Astrophysical Journal, vol. 1003, no. 2, article no. 122, American Astronomical Society; IOP Publishing, Jun 2026.
The definitive version is available at https://doi.org/10.3847/1538-4357/ae6329
Department(s)
Physics
Publication Status
Open Access
Keywords and Phrases
Cosmology (343); Gravitational waves (678); Hubble constant (758)
International Standard Serial Number (ISSN)
1538-4357; 0004-637X
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2026 The Authors, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
01 Jun 2026
