# Target of opportunity observations of blazars with H.E.S.S.

@inproceedings{Cerruti2016TargetOO,
title={Target of opportunity observations of blazars with H.E.S.S.},
author={M. Cerruti and Markus Bottcher and Nachiketa Chakraborty and I. D. Davids and Matthias Fussling and Felix Jankowsky and J.-P. Lenain and Manuel Meyer and Heike Prokoph and S. J. Wagner and D. N. Zaborov and Michael Zacharias and The H.E.S.S. Collaboration},
year={2016}
}
The very high energy (VHE, E > 100 GeV) sky is dominated by blazars, radio-loud active galactic nuclei whose relativistic jet is closely aligned with the line of sight. Blazars are characterized by rapid variability at all wavelengths and thus an important part of the H.E.S.S. blazar program is devoted to target of opportunity (ToO) observations. H.E.S.S. triggers blazar ToOs on the basis of publicly available blazar observations at longer wavelengths (optical, X-rays, and γ-rays), from private…
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