# Swift Observations of Mrk 421 in Selected Epochs. III. Extreme X-Ray Timing/Spectral Properties and Multiwavelength Lognormality during 2015 December–2018 April

@article{Kapanadze2020SwiftOO,
title={Swift Observations of Mrk 421 in Selected Epochs. III. Extreme X-Ray Timing/Spectral Properties and Multiwavelength Lognormality during 2015 December–2018 April},
author={B. Kapanadze and Alexandre Gurchumelia and Daniela Dorner and Stefano Vercellone and Patrizia Romano and P. A. Hughes and M. F. Aller and Hugh D. Aller and O. Kharshiladze},
journal={arXiv: Astrophysics of Galaxies},
year={2020}
}
We present the results from the timing and spectral study of Mrk\,421 based mainly on the \emph{Swift} data in the X-ray energy range obtained during the time interval 2015\,December--2018\,April. The most extreme X-ray flaring activity on the long-term, daily and intraday timescales was observed during the 2-month period which started in 2017\,December when the 0.3--10\,keV flux exceeded a level of 5$\times$10$^{-9}$erg\,cm$^{-2}$s$^{-1}$, recorded only twice previously. While the TeV-band and…
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