Improved short-segment detection statistic for continuous gravitational waves

Abstract

Continuous gravitational waves represent one of the long-sought types of signals that have yet to be detected. Due to their small amplitude, long observational datasets (months-years) have to be analyzed together, thereby vastly increasing the computational cost of these searches. All-sky searches face the most severe computational obstacles, especially searches for sources in unknown binary systems, which need to break the data into very short segments in order to be computationally feasible. In this paper, we present a new detection statistic that improves sensitivity by up to 19 % compared to the standard F-statistic for segments shorter than a few hours. II. THE STANDARD F-STATISTIC A. The continuous-waves likelihoodWe can parameterize the gravitational-wave signal from a non-axisymmetric rotating neutron star by four amplitude parameters A and several phase-evolution parameters λ. The four amplitude parameters consist of the overall signal amplitude h 0 , the inclination angle ι

Constraints on r-modes and Mountains on Millisecond Neutron Stars in Binary Systems

“…We use the coherent detection statistic  for all segments that have a well-conditioned antenna-pattern matrix with condition number <10 4 . For larger condition numbers, the  -statistic becomes numerically singular, and we use the constant antenna-pattern detection statistic with two degrees of freedom derived in Covas & Prix (2022).…”