Far-UV to mid-IR properties of nearby radio galaxies
  We investigate whether the far-UV continuum of nearby radio galaxies reveals
evidence for the presence of star forming or non-stellar components. If a UV
excess due to an extra radiation component exists we compare this with other
properties such as radio power, optical spectral type and the strength of the
emission lines. We also discuss the possible correlation between the
ultra-violet flux, IR properties and central black hole mass. We use two sampes
of low luminosity radio galaxies with comparable redshifts ($z < 0.2$).
Spectral Energy Distributions are constructed using a number of on-line
databases: GALEX, SDSS, 2MASS, and WISE. The parameter $XUV$ is introduced,
which measures the excess slope of the UV continuum between 4500 and 2000 \AA,
with respect to the UV radiation produced by the underlying old galaxy
component.
  We find that the UV excess is usually small or absent in low luminosity
sources, but sets in abruptly at the transition radio power above which we find
mostly FRII sources. $XUV$ behaves very similarly to the strength of the
optical emission lines (in particular $H\alpha$). Below $P_{1.4 GHz} < 10^{24}$
WHz$^{-1}$ $XUV$ is close to zero. $XUV$ correlates strongly with the $H\alpha$
line strength, but only in sources with strong $H\alpha$ emission. There is a
strong correlation between $XUV$ and the slope of the mid-IR, as measured by
the WISE bands in the interval 3.4 to 22 $\mu$m, in the sense that sources with
a strong UV excess also have stronger IR emission. There is an inverse
correlation between $XUV$ and central black hole mass: strong UV excess objects
have, on average, $M_{BH}$ about 2-3 times less massive than those without UV
excess. Low luminosity radio galaxies tend to be more massive and contain more
massive black holes.
