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In the framework of the TANAMI multi-wavelength and VLBI monitoring, we studythe evolution of the parsec-scale radio emission in radio galaxies in thesouthern hemisphere and their relationship to the $\gamma$-ray properties. Inthis first paper, we focus on Fermi-LAT-detected sources. We perform akinematic analysis for five $\gamma$-ray detected radio galaxies usingmulti-epoch 8.4 GHz VLBI images, deriving limits on intrinsic jet parameters.We analyzed Fermi-LAT data in order to study possible connections between the$\gamma$-ray properties and the pc-scale jets of Fermi-LAT-detected radiogalaxies, both in terms of variability and average properties. We discuss theindividual source results and draw preliminary conclusions on sample propertiesincluding published VLBI results from the MOJAVE survey, with a total offifteen sources. We find that the first $\gamma$-ray detection of Pictor Amight be associated with the passage of a new VLBI component through the radiocore. For the peculiar AGN PKS 0521-36, we detect subluminal parsec-scale jetmotions, and we confirm the presence of fast $\gamma$-ray variability in thesource down to timescales of 6 hours. We robustly confirm the presence ofsignificant superluminal motion, up to $\beta_{app}\sim$3, in the jet of theTeV radio galaxy PKS 0625-35. Finally, we place a lower limit on the age of theCompact Symmetric Object (CSO) PKS 1718-649. We draw some preliminaryconclusions on the relationship between pc-scale jets and $\gamma$-ray emissionin radio galaxies. We find that the VLBI core flux density correlates with the$\gamma$-ray flux, as seen in blazars. On the other hand, the $\gamma$-rayluminosity does not show any dependence on the core brightness temperature andcore dominance, two indicators of Doppler boosting, suggesting that$\gamma$-ray emission in radio galaxies is not driven by orientation-dependenteffects.

astronomy and astrophysics

Gamma-ray emission in radio galaxies under the VLBI scope -- I.  Parsec-scale kinematics and high-energy properties of $\gamma$-ray detected  TANAMI radio galaxies