A parsec-scale accelerating radio jet in the giant radio galaxy NGC 315

Observations of the core of the giant radio galaxy NGC 315 made with VLBI interferometers are discussed in the context of a relativistic jet. The sidedness asymmetry suggests Doppler favoritism from a relativistic jet. The presence of moving features in the jet, as well as jet counterjet brightness ratios, hint at an accelerating, relativistic jet. An increasing jet velocity is also supported by a comparison of the jet's observed properties with the predictions of an adiabatic expansion model. On the parsec scale, the jet is unpolarized at a wavelength of 6 cm to a very high degree, in clear distinction to the high polarization seen on the kiloparsec scale.