The radio - far infrared correlation in the faintest star forming dwarf
  galaxies
  We study the radio - far-infrared (FIR) correlation in a sample of faint
dwarf irregular galaxies using NVSS data for 1.4 GHz radio flux, Spitzer MIPS
70 um data for FIR flux, and GALEX FUV data to estimate the star formation
rates (SFR). Since our target galaxies are extremely faint, we stack images of
many galaxies together to estimate the average radio and FIR fluxes. We find
that for a given SFR both 70 um and 1.4 GHz fluxes are low compared to the
calibration for large spirals. Nonetheless, the ratio of 70 um to 1.4 GHz flux
agrees within errorbars with that seen for large galaxies. The radio-FIR
correlation thus appears to be the result of a 'conspiracy'. We use the SFR to
estimate the non-thermal fraction of the 1.4 GHz radio emission and find it to
be around 50%, much smaller than the 90% typical for spirals. We also estimate
the equipartition magnetic field and find it to be ~ 2 microgauss, about five
times smaller than that typical for spirals.
