| Abstract : | We present the results of studying the accretion disc vs jet power for a large fraction of all the blazars detected by the Fermi Gamma-Ray Space Telescope. The disc power is inferred from the emission line luminosities obtained from published results. As indicators of jet power, we use gamma-ray luminosity with and without a correction for beaming, low frequency radio luminosity from the extended jet, maximum speed of radio knots observed in the VLBA monitoring of the pc-scale jets, and kinetic energy of electrons in the jet deduced from the best-fit theoretical models of their spectral energy distribution. We obtain a significant correlation in most of those cases. However, we find that the correlations are often driven by the common redshift dependence of the compared quantities. In order to remove the redshift bias and probe the intrinsic correlation between the disc and jet power, we compute the partial correlation coefficient as well as the correlation in small redshift bins, and find that the intrinsic disc-jet correlation is weaker. In the cases, in which the common redshift dependence does not affect the result, we find that blazars do not exhibit high jet power for low disc luminosities while there are both high and low jet power for high disc luminosities. This result indicates that a powerful disc is a necessary but not sufficient condition to produce a powerful jet.
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