Followup procedure in time-domain F-statistic searches for continuous gravitational waves

TL;DR

This paper introduces a followup procedure for gravitational-wave candidate signals from all-sky searches, improving parameter estimation and confirmation accuracy using a multi-step process involving the F-statistic method.

Contribution

The paper presents a novel followup pipeline for gravitational-wave candidates that enhances parameter estimation and validation through a multi-stage analysis.

Findings

Initial candidate parameters are refined in the followup.

Separate and combined detector analyses improve signal confirmation.

The method effectively distinguishes true signals from noise.

Abstract

Potentially interesting gravitational-wave candidates (outliers) from the blind all-sky searches have to be confirmed or rejected by studying their origin and precisely estimating their parameters. We present the design and first results for the followup procedure of the {\tt Polgraw} all-sky search pipeline: a coherent search for almost-monochromatic gravitational-wave signals in several-day long time segments using the $F$-statistic method followed by the coincidences between the candidate signals. Approximate parameters resulting in these two initial steps are improved in the final followup step, in which the signals from detectors are studied separately, together with the network combination of them, and the true parameters and signal-to-noise values are established.