@article{ShuklaMannheim2020,
  author    = {Shukla, A. and Mannheim, K.},
  title     = {Gamma-ray flares from relativistic magnetic reconnection in the jet of the quasar 3C 279},
  series = {Nature Communications},
  volume    = {11},
  journal   = {Nature Communications},
  doi       = {10.1038/s41467-020-17912-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231328},
  year      = {2020},
  abstract  = {Spinning black holes in the centres of galaxies can release powerful magnetised jets. When the jets are observed at angles of less than a few degrees to the line-of-sight, they are called blazars, showing variable non-thermal emission across the electromagnetic spectrum from radio waves to gamma rays. It is commonly believed that shock waves are responsible for this dissipation of jet energy. Here we show that gamma-ray observations of the blazar 3C 279 with the space-borne telescope Fermi-LAT reveal a characteristic peak-in-peak variability pattern on time scales of minutes expected if the particle acceleration is instead due to relativistic magnetic reconnection. The absence of gamma-ray pair attenuation shows that particle acceleration takes place at a distance of ten thousand gravitational radii from the black hole where the fluid dynamical kink instability drives plasma turbulence.},
  language  = {en}
}
@article{SchleicherArbetEngelsBaacketal.2019,
  author    = {Schleicher, Bernd and Arbet-Engels, Axel and Baack, Dominik and Balbo, Matteo and Biland, Adrian and Blank, Michael and Bretz, Thomas and Bruegge, Kai and Bulinski, Michael and Buss, Jens and Doerr, Manuel and Dorner, Daniela and Elsaesser, Dominik and Grischagin, Sergej and Hildebrand, Dorothee and Linhoff, Lena and Mannheim, Karl and Mueller, Sebastian Achim and Neise, Dominik and Neronov, Andrii and Noethe, Maximilian and Paravac, Aleksander and Rhode, Wolfgang and Schulz, Florian and Sedlaczek, Kevin and Shukla, Amit and Sliusar, Vitalii and Willert, Elan and Walter, Roland},
  title     = {Fractional Variability—A Tool to Study Blazar Variability},
  series = {Galaxies},
  volume    = {7},
  journal   = {Galaxies},
  number    = {2},
  issn      = {2075-4434},
  doi       = {10.3390/galaxies7020062},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197348},
  year      = {2019},
  abstract  = {Active Galactic Nuclei emit radiation over the whole electromagnetic spectrum up to TeV energies. Blazars are one subtype with their jets pointing towards the observer. One of their typical features is extreme variability on timescales, from minutes to years. The fractional variability is an often used parameter for investigating the degree of variability of a light curve. Different detection methods and sensitivities of the instruments result in differently binned data and light curves with gaps. As they can influence the physics interpretation of the broadband variability, the effects of these differences on the fractional variability need to be studied. In this paper, we study the systematic effects of completeness in time coverage and the sampling rate. Using public data from instruments monitoring blazars in various energy ranges, we study the variability of the bright TeV blazars Mrk 421 and Mrk 501 over the electromagnetic spectrum, taking into account the systematic effects, and compare our findings with previous results. Especially in the TeV range, the fractional variability is higher than in previous studies, which can be explained by the much longer (seven years compared to few weeks) and more complete data sample.},
  language  = {en}
}