Searching for monochromatic signals in the ALLEGRO gravitational wave detector data

The detection of continuous gravitational wave (GW) signals is investigated using on a method developed for the detection of monochromatic signals in the middle of strong noise which makes power spectrum estimates using averaged modified periodograms. With this method it is possible to obtain a power spectrum for the data which preserves peaks due to monochromatic signals. In GW detection two kinds of Doppler shifts are expected, with annual and daily periods. Using the method an analysis is performed on persistent peaks, searching for frequency drifts that might present a pattern similar to the one due to Doppler shifts. For the chosen data set of the ALLEGRO gravitational wave detector it was found that none of the strongest, persistent peaks investigated presented a frequency drift with a Doppler shift pattern, thus excluding them as GW signal candidates.