Parameter-space correlations of the optimal statistic for continuous gravitational-wave detection

TL;DR

This paper analyzes the global correlation structure of the optimal detection statistic for continuous gravitational waves, revealing how parameter correlations influence detection and enabling veto methods for false alarms.

Contribution

It introduces a family of global-correlation equations describing the maximum structure of the detection statistic in parameter space for short observation times.

Findings

Global-correlation equations describe the detection statistic's maximum structure.

Intersection of hypersurfaces indicates the optimal detection points.

Veto method developed to exclude false candidate events.

Abstract

The phase parameters of matched-filtering searches for continuous gravitational-wave signals are sky position, frequency and frequency time-derivatives. The space of these parameters features strong global correlations in the optimal detection statistic. For observation times smaller than one year, the orbital motion of the Earth leads to a family of global-correlation equations which describes the "global maximum structure" of the detection statistic. The solution to each of these equations is a different hypersurface in parameter space. The expected detection statistic is maximal at the intersection of these hypersurfaces. The global maximum structure of the detection statistic from stationary instrumental-noise artifacts is also described by the global-correlation equations. This permits the construction of a veto method which excludes false candidate events.