Validating continuous gravitational-wave candidates from a semicoherent search using Doppler modulation and an effective point spread function

TL;DR

This paper develops and tests Doppler modulation-based veto procedures, including an effective point spread function, to improve the follow-up process in continuous gravitational wave searches, ensuring efficiency and safety.

Contribution

It introduces Doppler modulation-based vetoes and the concept of an effective point spread function for follow-up procedures in gravitational wave searches.

Findings

Veto procedures effectively reduce false candidates.

The methods are safe, minimizing false dismissals.

Guidelines for future search follow-ups are provided.

Abstract

Following up large numbers of candidates in continuous gravitational wave searches presents a challenge, particularly in regard to computational power and the time required to manually scrutinize each of the candidates. It is important to design and test good follow-up procedures that are safe (i.e., minimize false dismissals) and computationally efficient across many search configurations. We investigate two follow-up procedures, or "vetoes," both of which exploit the Doppler modulation predicted in astrophysical signals. In particular, we introduce the concept of using an effective point spread function as part of our veto criteria. We take advantage of a well-established semicoherent search algorithm based on a hidden Markov model to study various search configurations and to generalize the veto criteria by considering the overall veto performance in terms of efficiency and safety. The results can serve as a guideline for follow-up studies in future continuous gravitational wave searches using a hidden Markov model algorithm. The results also apply qualitatively to other semicoherent search algorithms.