With the exception of TXS 2355$-$003 [already discussed in @collet14a], we confirmed the previous redshifts of all galaxies. TXS 2355$-$003 lies at z$=$1.49, not at z$=$2.49, as previously estimated by @debreuck00.

Our choice of targets was guided by our aim to investigate how the radio properties of the AGN in our sample affect the warm ionized gas in their host galaxies. This makes it necessary to sample a range in radio properties as uniformly as possible rather than to match the radio luminosity function, as would be the case for a population study. In Fig. \[fig:sample\] we compare the distribution of radio power of our galaxies with the radio luminosity function of @willott01 of very powerful high-z radio sources. Our sample is very naturally biased towards galaxies with bright emission lines, corresponding to the “high-excitation line” mode of radio galaxies, or the “Quasar mode” of AGN feedback models, which in turn correspond to the high-power population of @willott01. The figure illustrates that we sample a range in radio power from $10^{26.3}$ to $10^{29.3}$ W Hz$^{-1}$, covering the entire range of about three orders of magnitude that is characteristic for this population, which, according to @willott01, fades quickly towards lower redshift. 