A Sample of Long-period Binaries with Dormant Compact-object Candidates from LAMOST DR13 MRS and Gaia DR3
- 1Xiamen University
Abstract
Identifying dormant compact objects in noninteracting binaries is crucial for constraining the hidden population of stellar remnants. We present a systematic search for long-period compact-object candidates by combining Gaia DR3 astrometry with multiepoch LAMOST DR13 medium-resolution spectroscopy. Starting from sources with elevated RUWE values, we required at least five LAMOST spectroscopic epochs and peak-to-peak radial velocity (RV) variations exceeding 20 km s ⁻¹ . After RV extraction, orbital fitting, and subsequent screening, we obtained Bayesian Keplerian orbital solutions for 19 long-period single-lined binary candidates, with periods spanning approximately 30–1500 days. Multiwavelength spectral energy distribution fitting was used to constrain the visible stars and evaluate the expected luminosities of unseen companions under a main-sequence assumption. Two systems are identified as the highest-priority compact-object candidates in our sample, each with a minimum companion mass exceeding 1 M ⊙ . Their spectra and optical-to-infrared photometry show no detectable secondary-light contribution, although such a contribution would be expected if the unseen companions were normal main-sequence stars. These systems therefore represent the strongest compact-object candidates in our sample, although further observations are required to distinguish massive white dwarfs or neutron stars from faint stellar companions or unresolved hierarchical systems. We also identify five intermediate-priority and 12 lower-priority systems for follow-up spectroscopy, ultraviolet imaging, and future astrometric constraints.
Related
- A Systematic Gaia–ZTF Search for Short-period Blue Compact-binary Candidates
- BSN-VIII: Detailed Photometric Modeling of Ten W UMa Contact Binaries and a Revised Empirical Period-Mass Relationship
- Hunting for Compact Object Binaries from eRASS1 Optical Counterparts through ZTF Time-domain Photometry and Multi-wavelength Surveys
- Hunting for Compact Object Binaries from eRASS1 Optical Counterparts through ZTF Time-domain Photometry and Multiwavelength Surveys
- Metallicity dependence of Wolf-Rayet binaries using detailed binary models: An absence of long-period systems at low metallicity
BibTeX
@article{zhou2026sample,
title = {{A Sample of Long-period Binaries with Dormant Compact-object Candidates from LAMOST DR13 MRS and Gaia DR3}},
author = {Junxing Zhou and Wei-Min Gu},
journal = {The Astrophysical Journal},
year = {2026},
month = oct,
doi = {10.3847/1538-4357/aeaa3a},
url = {https://iopscience.iop.org/article/10.3847/1538-4357/aeaa3a},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - A Sample of Long-period Binaries with Dormant Compact-object Candidates from LAMOST DR13 MRS and Gaia DR3
AU - Junxing Zhou
AU - Wei-Min Gu
PY - 2026
DA - 2026/10/19
JO - The Astrophysical Journal
DO - 10.3847/1538-4357/aeaa3a
UR - https://iopscience.iop.org/article/10.3847/1538-4357/aeaa3a
AB - Identifying dormant compact objects in noninteracting binaries is crucial for constraining the hidden population of stellar remnants. We present a systematic search for long-period compact-object candidates by combining Gaia DR3 astrometry with multiepoch LAMOST DR13 medium-resolution spectroscopy. Starting from sources with elevated RUWE values, we required at least five LAMOST spectroscopic epochs and peak-to-peak radial velocity (RV) variations exceeding 20 km s ⁻¹ . After RV extraction, orbital fitting, and subsequent screening, we obtained Bayesian Keplerian orbital solutions for 19 long-period single-lined binary candidates, with periods spanning approximately 30–1500 days. Multiwavelength spectral energy distribution fitting was used to constrain the visible stars and evaluate the expected luminosities of unseen companions under a main-sequence assumption. Two systems are identified as the highest-priority compact-object candidates in our sample, each with a minimum companion mass exceeding 1 M ⊙ . Their spectra and optical-to-infrared photometry show no detectable secondary-light contribution, although such a contribution would be expected if the unseen companions were normal main-sequence stars. These systems therefore represent the strongest compact-object candidates in our sample, although further observations are required to distinguish massive white dwarfs or neutron stars from faint stellar companions or unresolved hierarchical systems. We also identify five intermediate-priority and 12 lower-priority systems for follow-up spectroscopy, ultraviolet imaging, and future astrometric constraints.
SN - 0004-637X
SN - 1538-4357
ER -