Yannis Liodakis (Univ.Turku)
Radio-loud AGN in the discovery era of X-ray polarimetry
X-ray polarization is a crucial probe of the magnetic field structure and emission processes in astrophysical systems. This is particularly true for active galactic nuclei (AGN). In radio-loud AGN, X-ray polarimetry allows us to investigate particle acceleration and composition in jets. Until now, polarization observations have been limited to the radio-to-optical range, thereby leaving a gap in our knowledge of the processes and physical conditions in the most energetic objects. The recently launched Imaging X-ray Polarimetry Explorer -- IXPE, the first X-ray polarization mission to target AGN, offers a radically new way of studying high-energy processes in relativistic jets. I will discuss the multiwavelength polarization observations and results from the first year of IXPE observations of radio galaxies and blazars that clearly demonstrate the importance of X-ray polarization in our understanding of the Universe.