Comparison of Spectral Properties of Microwave Background Inhomogeneities on Planck Multi-Frequency Maps Near RCR Catalog Sources with Spectral Properties of NVSS and Planck Catalog Sources

The combined spectra of RCR sources and the positive spots closest to them on the Planck maps have the advantage is true for the objects of the first group. The filled black circles denote the flux densities of RCR objects from the available catalogs, the red filled circles are the estimated values of the spot flux densities.

Majorova E. K., Zhelenkova O. P.

The study of the relationship of positive fluctuations on Planck frequency maps with the nearest radio sources of the RCR catalog (RATAN Cold Refined) was continued. A linear correlation was found between the spectral indices of radio sources at frequencies of 1.4 and 3.94 GHz and the spectral indices of the nearest spots in the frequency range of 30-217 GHz. The spectral indices of NVSS sources in the range of 150 MHz-3.94 GHz were compared with the spectral indices of the nearest objects of the Planck catalog in the range of 30-217 GHz, between which a linear correlation was also found. The dependences between the spectral indices of RCR sources and the spectral indices of spots and the dependences between the spectral indices of NVSS sources and the objects of the Planck catalog turned out to be identical. The differences in the tangents of the angles of inclination of the approximating lines of these dependencies ranged from 8 to 21%. Combined spectra are constructed for RCR sources and the nearest positive spots, as well as for NVSS sources and the nearest objects of the Planck catalog. It is shown that some of the spots detected near RCR objects are most likely their manifestation in the submillimeter range. In a larger group of spots whose flux densities exceed the flux densities of radio sources extrapolated to the microwave region of the spectrum, these discrepancies may be due to inaccuracy of calibrations or a random coincidence of their coordinates. However, a more detailed study of the combined spectra of NVSS and Planck sources in the range of 70 MHz-857 GHz showed that the shape of the spectra of RCR objects and nearby spots can be explained by the variability of radio sources. The spectrum of averaged temperatures of hot spots detected near RCR sources was constructed, which showed a quantitative excess over those obtained earlier by modeling, which can be explained by the influence of synchrotron background or the contribution of radio sources or their host galaxies to radiation in the submillimeter range. The appearance of the obtained spectrum indicates that most of the spots have an extragalactic nature. The obtained statistics of spectral indices confirm the connection of radio sources with the nearest positive spots on Planck frequency maps. We believe that the contribution of unaccounted radio sources to the foreground may affect the resulting map of the cosmological microwave background. Original →