New Potential Ultracompact X-Ray Binaries for Space-based Gravitational-wave Detectors from a Low-mass Main-sequence Companion Channel

Bibliographic Details
Title: New Potential Ultracompact X-Ray Binaries for Space-based Gravitational-wave Detectors from a Low-mass Main-sequence Companion Channel
Authors: Minghua Chen, Jinzhong Liu
Source: The Astrophysical Journal, Vol 981, Iss 2, p 175 (2025)
Publisher Information: IOP Publishing, 2025.
Publication Year: 2025
Collection: LCC:Astrophysics
Subject Terms: X-ray binary stars, Gravitational waves, Compact binary stars, Space telescopes, Astrophysics, QB460-466
More Details: We investigate the formation and evolution of ultracompact X-ray binaries (UCXBs) using the COMPAS binary evolution code, starting from the zero-age main sequence (MS). Focusing on the low-mass MS companion channel, we simulate gravitational-wave (GW) signals from UCXBs with LEGWORK and evaluate their detectability by space-based observatories such as Taiji and TianQin. By incorporating signal-to-noise ratio (SNR) calculations with a threshold of SNR > 5, we provide a realistic framework to assess the detectability of the GW source. Our analysis suggests that the Milky Way currently hosts 7–32 observable UCXBs from the MS companion channel. Taiji or LISA alone could detect one to six sources over an 8 yr observation period, while TianQin, due to its high-frequency sensitivity, contributes to detecting systems with extremely short orbital periods and can also detect one to four sources. Comparison with sensitivity curves validates UCXBs as detectable GW sources, particularly at greater Galactic distances. This study improves our understanding of the evolution of UCXBs and their role as GW sources. By integrating population synthesis, SNR-based analyses, and observational data, we establish UCXBs as significant targets for GW astronomy, paving the way for future missions and theoretical studies of compact binary systems.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1538-4357
Relation: https://doaj.org/toc/1538-4357
DOI: 10.3847/1538-4357/adb618
Access URL: https://doaj.org/article/23661f58fe2d47a897ca3e2ad7e01384
Accession Number: edsdoj.23661f58fe2d47a897ca3e2ad7e01384
Database: Directory of Open Access Journals
More Details
ISSN:15384357
DOI:10.3847/1538-4357/adb618
Published in:The Astrophysical Journal
Language:English