A comparison of methods for the detection of gravitational waves from unknown neutron stars

Rapidly rotating neutron stars are promising sources of continuousgravitational wave radiation for the LIGO and Virgo interferometers. Themajority of neutron stars in our galaxy have not been identified withelectromagnetic observations. All-sky searches for isolated neutron stars offerthe potential to detect gravitational waves from these unidentified sources.The parameter space of these blind all-sky searches, which also cover a largerange of frequencies and frequency derivatives, presents a significantcomputational challenge. Different methods have been designed to perform thesesearches within acceptable computational limits. Here we describe the firstbenchmark in a project to compare the search methods currently available forthe detection of unknown isolated neutron stars. We employ a mock datachallenge to compare the ability of each search method to recover signalssimulated assuming a standard signal model. We find similar performance amongthe short duration search methods, while the long duration search methodachieves up to a factor of two higher sensitivity. We find the absence ofsecond derivative frequency in the search parameter space does not degradesearch sensivity for signals with physically plausible second derivativefrequencies. We also report on the parameter estimation accuracy of each searchmethod, and the stability of the sensitivity in frequency, frequency derivativeand in the presence of detector noise.