Robustness of Template-based Search for Continuous Gravitational Waves with Glitches

The detection of continuous gravitational waves (CWs) from rapidly rotating neutron stars becomes increasingly promising with longer LIGO–Virgo–KAGRA observing runs. However, glitches—sudden spin-up events that disrupt the signal phase evolution—pose challenges for template-based directed searches and their follow-up procedures, which typically assume glitch-free waveforms. In this study, we study the impact of glitches on the upper limits and the robustness of the follow-up procedure that increases coherence time while requiring an increased mean F-statistic. Using simulated data, we quantify sensitivity loss and parameter estimation biases introduced by glitches. We then present a follow-up strategy that can recover glitching signals using a waveform model without explicit glitch assumptions. This approach improves the reliability of CW searches and reduces the risk of missed detections.