The $\textit{Chandra}$ 3CR extragalactic survey at high redshift

TL;DR

This paper analyzes nine high-redshift 3CR radio sources observed with Chandra, detecting X-ray emission from nuclei and lobes, and suggests that the extended X-ray emission is likely due to IC/CMB scattering in radio lobes.

Contribution

It completes the 3CR Chandra Snapshot Survey at high redshift, providing X-ray measurements for all sources and analyzing the origin of extended X-ray emission.

Findings

X-ray emission detected in all nuclei except two sources.

X-ray emission from radio lobes in 6 out of 9 sources.

Extended X-ray emission spatially coincides with radio structures, likely due to IC/CMB.

Abstract

We present the analysis of nine radio sources belonging to the Third Cambridge Revised catalog (3CR) observed with $Chandra$ during Cycle 20 in the redshift range between 1.5 and 2.5. This study completes the 3CR $Chandra$ Snapshot Survey thus guaranteeing the X-ray coverage of all 3CR sources identified to date. This sample lists two compact steep spectrum sources, four radio galaxies and three quasars. We detected X-ray emission from all nuclei, with the only exception of 3C 326.1 and 3C 454.1 and from radio lobes in 6 out of 9 sources at level of confidence larger than $\sim$5$\sigma$. We measured X-ray fluxes and luminosities for all nuclei and lobes in the soft (0.5 - 1 keV), medium (1 - 2 keV) and hard (2 - 7 keV) X-ray bands. Since the discovered X-ray extended emission is spatially coincident with the radio structure in all cases, its origin could be due to Inverse Compton scattering of the Cosmic Microwave Background (IC/CMB) occurring in radio lobes.