Probing More Deeply in an All-Sky Search for Continuous Gravitational Waves in the LIGO O3 Data Set

The LIGO-Virgo O3 data set offers not only detection of now-familiar compact binary mergers of distant black holes and neutron stars, but potentially the detection of much weaker but continuous radiation from nearby rapidly spinning, non-axisymmetric neutron stars in the galaxy. All-sky searches for such radiation from previously unknown stars using necessarily long data sets are computationally challenging and have given rise to several different approaches. We describe here the application of the well established PowerFlux program to a new all-sky search of the LIGO data from the O3 observing run. In order to probe the O3 data more deeply than in a previously published O3 PowerFlux search, we apply loose coherence and coherent summing of LIGO Hanford and Livingston data in the first stage of the hierarchical search. The details of the search, its chosen parameters, and results will be presented.