The nature of the extreme kinematics in the extended gas of high redshift radio galaxies

TL;DR

This paper investigates the high-velocity gas in high-redshift radio galaxies, suggesting jet interactions and other processes contribute to extreme kinematics in their extended gas regions.

Contribution

It provides UV spectra of high-redshift radio galaxies and discusses multiple mechanisms behind extreme gas velocities beyond jet interactions.

Findings

High velocities (FWHM>1000 km/s) observed in extended gas.

Jet interactions likely cause shocks and acceleration.

Other processes may also contribute to gas kinematics.

Abstract

We present UV rest frame spectra of 3 powerful narrow line radio galaxies and the hyperluminous type 2 active galaxy SMM02399-0136, all at high redshift (z>2). We find high velocities (FWHM>1000, km/s) in the extended gas of all objects. A natural explanation is the interaction between the radio jet and the ambient gas, that drives shocks into the gas and accelerates the clouds. However, the existence of high velocities in regions where such interactions are not taking place implies that other processes can play a role. We discuss here several possible mechanisms.