Using the methods of wavelet analysis and singular spectrum analysis in the study of the variability of flux of radio sources 3C120 and BL Lac in the radio range
Abstract
We investigated the monitoring data of extragalactic sources 3C120 and BL Lac. This monitoring was held with University of Michigan 26-meter radio telescope. To study flux density of extragalactic sources 3C120 and BL Lac at frequencies of 14.5, 8 and 4.8 GHz, the wavelet analysis and singular spectrum analysis were used. Calculating the integral wavelet spectra revealed long-term components (11 - 4 years) and short-term components (3.4 - 0.7 years) in 3C120. BL Lac has long-period components of 7 - 8 years and short-term components of 1 - 4 years. Studying of VLBI radio maps (by the program Mojave) allowed investigating features of components movement relatively to the VLBI core. The data of radio astronomy observations were also investigated using singular spectrum analysis. This method does not use the analyzing function, so its calculations allow to distinguish various components of investigated series with a high accuracy. To get spectral power distribution depending on time in the studied narrowband components obtained by singular spectrum analysis, short-term Fourier transformation was used.
- Publication:
-
Extragalactic Jets from Every Angle
- Pub Date:
- March 2015
- DOI:
- 10.1017/S1743921315001908
- Bibcode:
- 2015IAUS..313...76D
- Keywords:
-
- galaxies: active;
- galaxies: jets