In Search of the Gravitational Wave of Fast X-Ray Transient in the Second Part of the LIGO-Virgo-KAGRA Fourth Observing Run
Abstract
Fast X-ray Transients (FXTs) are brief, intense X-ray flashes unassociated with persistent X-ray sources or known stellar objects, typically lasting from seconds to hours. With the launch of the Einstein Probe in January 2024, the study of FXTs has entered a new phase. Its large field of view significantly increases the discovery rate, enabling more robust statistics. The leading discoveries have revealed a fraction of gamma-ray bursts, while the rest remain unexplained. We propose a methodology to search for possible relations between gravitational waves (GWs) and FXTs, as it may serve as a discrepancy among proposed theoretical models. To achieve this, we intend to utilize X-Pipeline, an unmodeled search algorithm, to identify excess coherent signals in LIGO-Virgo-KAGRA (LVK) O4b observations. Out of 64 FXTs events, we obtained 19 FXTs for constructing robust searches. Given the absence of any detectable GW signals, we subsequently calculated upper limits and estimated exclusion distances for each source. In order to enrich the sample base and statistical analysis, this methodology could henceforth be conducted through future GW searches, including KAGRA in the O4c and O5 observations.
Related
- GWTC-5.0: Observations from the Second Part of the Fourth LIGO-Virgo-KAGRA Observing Run and Updates to the Gravitational-Wave Transient Catalog
- Search for Sub-Solar Mass Binaries in the First and Second Part of LIGO's Fourth Observing Run O4a-O4b
- GWTC-4.0: Updating the Gravitational-wave Transient Catalog with Observations from the First Part of the Fourth LIGO–Virgo–KAGRA Observing Run
- Direct multi-model dark-matter search with gravitational-wave interferometers using data from the first part of the fourth LIGO-Virgo-KAGRA observing run
- Search for Compact Binary Coalescences with Sub-solar Mass Components in Data from the Second Part of LIGO-Virgo-KAGRA's Fourth Observing Run
BibTeX
@misc{wang2026search,
title = {{In Search of the Gravitational Wave of Fast X-Ray Transient in the Second Part of the LIGO-Virgo-KAGRA Fourth Observing Run}},
author = {Po-Ya Wang and Albert K. H. Kong and Surojit Saha},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.31227},
eprint = {2610.31227},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.31227},
}
RIS
TY - UNPB
TI - In Search of the Gravitational Wave of Fast X-Ray Transient in the Second Part of the LIGO-Virgo-KAGRA Fourth Observing Run
AU - Po-Ya Wang
AU - Albert K. H. Kong
AU - Surojit Saha
PY - 2026
DA - 2026/10/22
PB - arXiv
DO - 10.48550/arxiv.2610.31227
UR - https://arxiv.org/abs/2610.31227
AB - Fast X-ray Transients (FXTs) are brief, intense X-ray flashes unassociated with persistent X-ray sources or known stellar objects, typically lasting from seconds to hours. With the launch of the Einstein Probe in January 2024, the study of FXTs has entered a new phase. Its large field of view significantly increases the discovery rate, enabling more robust statistics. The leading discoveries have revealed a fraction of gamma-ray bursts, while the rest remain unexplained. We propose a methodology to search for possible relations between gravitational waves (GWs) and FXTs, as it may serve as a discrepancy among proposed theoretical models. To achieve this, we intend to utilize X-Pipeline, an unmodeled search algorithm, to identify excess coherent signals in LIGO-Virgo-KAGRA (LVK) O4b observations. Out of 64 FXTs events, we obtained 19 FXTs for constructing robust searches. Given the absence of any detectable GW signals, we subsequently calculated upper limits and estimated exclusion distances for each source. In order to enrich the sample base and statistical analysis, this methodology could henceforth be conducted through future GW searches, including KAGRA in the O4c and O5 observations.
ER -