  Motivated by the detection of a hardening in the gamma-ray spectrum of the
radio galaxy Centaurus A, we have analysed ~10 years of Fermi-LAT observations
of 26 radio galaxies to search for similar spectral features. We find that the
majority of the radio galaxies' gamma-ray spectral energy distributions are
best fitted with a simple power-law model, and no spectral hardening similar to
that found in Centaurus A was detected. We show that, had there been any such
spectral features present in our sample of radio galaxies, they would have been
seen, but note that 7 of the radio galaxies (3C 111, 3C 120, 3C 264, IC 4516,
NGC 1218, NGC 2892 and PKS 0625-35) show evidence for flux variability on
6-month timescales, which makes the detection of any steady spectral features
difficult. We find a strong positive correlation (r = 0.9) between the core
radio power at 5 GHz and the gamma-ray luminosity and, using a simple
extrapolation to TeV energies, we expect around half of the radio galaxies
studied will be detectable with the forthcoming Cherenkov Telescope Array.

High Energy Astrophysical Phenomena