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arXiv · 2103.04994

A Hard Look At Relativistic Reverberation in MCG-5-23-16 & SWIFT J2127.4+5654: Testing the Lamp-Post Model

A. Zoghbi·J. M. Miller·E. Cackett
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Abstract

X-ray reverberation mapping has emerged as a new tool to probe accretion in AGN, providing a potentially powerful probe of accretion at the black hole scale. The lags, along with relativistic spectral signatures are often interpreted in light of the lamp-post model. Focusing specifically on testing the prediction of the relativistic reverberation model, we have targeted several of the brightest Seyfert Galaxies in X-rays with different observing programs. Here, we report the results from two large campaigns with NuSATR targeting MCG-5-23-16 and SWIFT J2127.4+5654 to test the model predictions in the 3-50 keV band. These are two of three sources that showed indications of a delayed Compton hump in early data. With triple the previously analyzed exposures, we find no evidence for relativistic reverberation in MCG-5-23-16, and the energy-dependent lags are consistent with a log-linear continuum. In SWIFT J2127.4+5654, although a continuum-only model explains the data, the relativistic reverberation model provides a significant improvement to the energy and frequency-dependent lags, but with parameters that are not consistent with the time-averaged spectrum. This adds to mounting evidence showing that the lag data is not consistent with a static lamp-post model.

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A. Zoghbi, J. M. Miller, E. Cackett. 2021-03-08. A Hard Look At Relativistic Reverberation in MCG-5-23-16 & SWIFT J2127.4+5654: Testing the Lamp-Post Model. https://doi.org/10.3847/1538-4357%2Fabebd9

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