  All very massive early-type galaxies contain supermassive blackholes but are
these blackholes all sufficiently active to produce detectable radio continuum
sources? We have used the 887.5~MHz Rapid ASKAP Continuum Survey DR1 to measure
the radio emission from morphological early-type galaxies brighter than
$K_S=9.5$ selected from the 2MASS Redshift Survey, HyperLEDA and RC3. In line
with previous studies, we find median radio power increases with infrared
luminosity, with $P_{1.4} \propto L_K^{2.2}$, although the scatter about this
relation spans several orders of magnitude. All 40 of the $M_K<-25.7$
early-type galaxies in our sample have measured radio flux densities that are
more than $2\sigma$ above the background noise, with $1.4~{\rm GHz}$ radio
powers spanning $\sim 3 \times 10^{20}$ to $\sim 3\times 10^{25}~{\rm
W~Hz^{-1}}$. Cross matching our sample with integral field spectroscopy of
early-type galaxies reveals that the most powerful radio sources preferentially
reside in galaxies with relatively low angular momentum (i.e. slow rotators).
While the infrared colours of most galaxies in our early-type sample are
consistent with passive galaxies with negligible star formation and the radio
emission produced by active galactic nuclei or AGN remnants, very low levels of
star formation could power the weakest radio sources with little effect on many
other star formation rate tracers.
