In Search of the Gravitational Wave of Fast X-Ray Transient in the Second Part of the LIGO-Virgo-KAGRA Fourth Observing Run
Year: 2026
Type: article
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 2024 January, 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 (GRBs), 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.
Authors: Po-Ya Wang, Albert K. H. Kong, Surojit Saha
Institution: National Tsing Hua University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,325
OpenAlex ID: W7223355407
