Analysis of time series in space maser signals

Astronomy and Astrophysics. 2015. Vol. 574. No. L2. P. 1–4.

Siparov S., Samodurov V., Laptev G.

Many astrophysical sources that emit narrow radio-frequency spectral lines are believed to be sets of molecular condensation, each of which works as a maser, so that the whole set produces a characteristic spectrum. The forms of these spectra vary with time on various time-scales from months to dozens of minutes. We analysed the ultra-short variations of the separate components of space maser spectra in search for the periodical behaviour. We used a consecutive statistical analysis of the observation data that includes fast Fourier transformations (FFTs), a Lomb-Scargle procedure, and a modified Lomb-Scargle procedure. In at least 8 of the 49 sources we studied, we found that the intensity of one of the components of a space maser spectrum that corresponds to a single condensation changes periodically with a period of dozens of minutes or hours. Three sources had a period of 68 min; in one source the oscillations lasted at least four days.

Keywords: gravitational waves, masers, binaries, гравитационные волны, космические мазеры, двойные звезды, математическая обработка данных, периодические флуктуации