Clues to the origin of parsec to kilo-parsec jet misalignments in EGRET sources

Abstract

The apparent position angle difference $Δ$PA between parsec and kilo-parsec jets in blazars can be related to the bending properties of the jets. We present correlations between the misalignment $Δ$PA and the ratio of radio to broad-line emission for a sample of $γ$-ray blazars. The present study is limited to EGRET sources due to uniform data for the radio and optical properties of these sources being easily available. The broad-line emission is known to be a good indicator of the accretion power for both steep and flat-spectrum quasars. We find significant correlations between $Δ$PA and the ratio of radio flux (total and radio core flux respectively) to broad-line flux, which is consistent with the beaming scenario. A weak correlation between $Δ$PA and the ratio of extended radio to broad-line flux might imply that the intrinsic bend of the jet is related with the ratio of jet mechanical power to accretion power.