English

Is PKS 0625-354 another variable TeV active galactic nucleus?

High Energy Astrophysical Phenomena 2021-08-04 v1

Abstract

The majority of the active galactic nuclei (AGN) detected at very-high-energies above 100 GeV belong to the class of blazars with a small angle between the jet-axis and the line-of-sight. Only about 10 percent of the gamma-ray AGN are objects with a larger viewing angle resulting in a smaller Doppler boosting of the emission. Originally, it was believed that gamma-ray emission can only be observed from blazars and those are variable in its brightness. Instead, the last years have shown that non-blazar active galaxies also show a fascinating variability behaviour which provide important new insights into the physical processes responsible for the gamma-ray production and especially for flaring events. Here, we report on the observation of gamma-ray variability of the active galaxy PKS 0625-354 detected with the H.E.S.S. telescopes in November 2018. The classification of PKS 0625-354 is a still matter of debate. The H.E.S.S. measurements were performed as part of a flux observing program and showed in the first night of the observation a detection of the object with >5sigma. A denser observation campaign followed for the next nine nights resulting in a decrease of the gamma-ray flux. Those observations were accompanied with Swift in the X-ray and UV/optical band allowing for the reconstruction of a multi-band broad-band spectral energy distribution. We will discuss the implications of the gamma-ray variability of the object.

Keywords

Cite

@article{arxiv.2108.01331,
  title  = {Is PKS 0625-354 another variable TeV active galactic nucleus?},
  author = {Dorit Glawion and Alicja Wierzcholska},
  journal= {arXiv preprint arXiv:2108.01331},
  year   = {2021}
}

Comments

Proceedings of the 37th International Cosmic Ray Conference (ICRC 2021)

R2 v1 2026-06-24T04:46:55.934Z