Abstract: | We report on an all-sky search for periodic gravitational waves in the
frequency band 20-475 Hz and with a frequency time derivative in the range of
[-1.0, +0.1]e-8 Hz/s. Such a signal could be produced by a nearby spinning and
slightly non-axisymmetric isolated neutron star in our galaxy. This search uses
the data from Advanced LIGO’s first observational run, O1. No periodic
gravitational wave signals were observed, and upper limits were placed on their
strengths. The lowest upper limits on worst-case (linearly polarized) strain
amplitude h0 are 4e-25 near 170 Hz. For a circularly polarized source (most
favorable orientation), the smallest upper limits obtained are 1.5e-25. These
upper limits refer to all sky locations and the entire range of frequency
derivative values. For a population-averaged ensemble of sky locations and
stellar orientations, the lowest upper limits obtained for the strain amplitude
are 2.5e-25. |