1,184 research outputs found

    Signatures of the disk-jet coupling in the Broad-line Radio Quasar 4C+74.26

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    Here we explore the disk-jet connection in the broad-line radio quasar 4C+74.26, utilizing the results of the multiwavelength monitoring of the source. The target is unique in that its radiative output at radio wavelengths is dominated by a moderately-beamed nuclear jet, at optical frequencies by the accretion disk, and in the hard X-ray range by the disk corona. Our analysis reveals a correlation (local and global significance of 96\% and 98\%, respectively) between the optical and radio bands, with the disk lagging behind the jet by 250±42250 \pm 42 days. We discuss the possible explanation for this, speculating that the observed disk and the jet flux changes are generated by magnetic fluctuations originating within the innermost parts of a truncated disk, and that the lag is related to a delayed radiative response of the disk when compared with the propagation timescale of magnetic perturbations along relativistic outflow. This scenario is supported by the re-analysis of the NuSTAR data, modelled in terms of a relativistic reflection from the disk illuminated by the coronal emission, which returns the inner disk radius Rin/RISCO=35−16+40R_{\rm in}/R_{\rm ISCO} =35^{+40}_{-16}. We discuss the global energetics in the system, arguing that while the accretion proceeds at the Eddington rate, with the accretion-related bolometric luminosity Lbol∼9×1046L_{\rm bol} \sim 9 \times 10^{46} erg s−1^{-1} ∼0.2LEdd\sim 0.2 L_{\rm Edd}, the jet total kinetic energy Lj∼4×1044L_\textrm{j} \sim 4 \times 10^{44} erg s−1^{-1}, inferred from the dynamical modelling of the giant radio lobes in the source, constitutes only a small fraction of the available accretion power.Comment: 9 pages and 6 figures, ApJ accepte

    The Examination of Confidentiality in A School Based Setting

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    This research study explored the policies and procedures that education systems abide by, as well as how these policies are enforced to protect the confidentiality of dependent children’s private information from being exposed in their schools to non-relatives and uninvolved parties to their case. Elementary, middle school, and high school faculty’s perception of confidentiality was explored to identify individual competence when working with social workers during their direct contact visit with dependent children on school premises. Data collection included anonymous online surveys of 30-school faculty of various schools in the Southern California. There were no significant findings to support school faculty’s lack of competence of confidentiality protocol when a Department of Children and Family Service social worker conducts a visit on school premises. Future research should involve a qualitative study of school faculty perceptions to gain more accurate and unbiased information from participants
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