On the Spectral Index of Distant Radio Galaxies

TL;DR

This paper investigates the spectral index of distant radio galaxies, establishing a new spectral index-redshift relation from a large catalog, and discusses its implications for identifying distant sources.

Contribution

It introduces a new catalog of 2442 radio galaxies and derives an analytical spectral index-redshift relation for the first time.

Findings

New catalog of 2442 radio galaxies created.

Analytical spectral index-redshift relation established.

Distribution features on spectral index diagrams analyzed.

Abstract

The problems of using the spectral index of radio galaxies in various tests, in particular, in selecting distant radio sources are considered. The history of the question of choosing a criterion of searching for distant radio galaxies based on the spectral index is presented. For a new catalog of 2442 radio galaxies constructed from NED, SDSS, and CATS data, an analytical form of the sp ectral index.redshift relation has been determined for the first time. The spectral index.angular size and spectral index.flux density diagrams have also been constructed. Peculiarities of the distribution of sources on these diagrams are discussed.