Jurkevich Period Analysis of a Blazar Sample in Radio Band

Abstract In order to investigate the periodical properties of radio sources, we analyze the light curves of a sample of 78 blazars observed by OVRO (Owens Valley Radio Observatory) at 15 GHz using the Jurkevich method, and find that the radio sources display a significant light period in range of 0.83 to 2.55 years. In addition, we also estimate the modulation index of variability for each source, and find the Gauss distribution of the peak value of the modulation index in FSRQs (Flat Spectrum Radio Quasars) is smaller than the corresponding distribution peak in BL Lacs (BL Lacertae Objects).