Investigating the Properties of the Relativistic Jet and Hot Corona in AGN with X-ray Polarimetry

Dawoon E. Kim; Laura Di Gesu; Frédéric Marin; Alan P. Marscher; Giorgio Matt; Paolo Soffitta; Francesco Tombesi; Enrico Costa; Immacolata Donnarumma

arXiv · 2404.14200

Investigating the Properties of the Relativistic Jet and Hot Corona in AGN with X-ray Polarimetry

Dawoon E. Kim·Laura Di Gesu·Frédéric Marin·Alan P. Marscher·Giorgio Matt·Paolo Soffitta·Francesco Tombesi·Enrico Costa·Immacolata Donnarumma

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Abstract

X-ray polarimetry has been suggested as a prominent tool for investigating the geometrical and physical properties of the emissions from active galactic nuclei (AGN). The successful launch of the Imaging X-ray Polarimetry Explorer (IXPE) on 9 December 2021 has expanded the previously restricted scope of polarimetry into the X-ray domain, enabling X-ray polarimetric studies of AGN. Over a span of two years, IXPE has observed various AGN populations, including blazars and radio-quiet AGN. In this paper, we summarize the remarkable discoveries achieved thanks to the opening of the new window of X-ray polarimetry of AGN through IXPE observations. We will delve into two primary areas of interest: first, the magnetic field geometry and particle acceleration mechanisms in the jets of radio-loud AGN, such as blazars, where the relativistic acceleration process dominates the spectral energy distribution; and second, the geometry of the hot corona in radio-quiet AGN. Thus far, the IXPE results from blazars favor the energy-stratified shock acceleration model, and they provide evidence of helical magnetic fields inside the jet. Concerning the corona geometry, the IXPE results are consistent with a disk-originated slab-like or wedge-like shape, as could result from Comptonization around the accretion disk.

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Dawoon E. Kim, Laura Di Gesu, Frédéric Marin, Alan P. Marscher, Giorgio Matt, Paolo Soffitta, Francesco Tombesi, Enrico Costa, Immacolata Donnarumma. 2024-04-22. Investigating the Properties of the Relativistic Jet and Hot Corona in AGN with X-ray Polarimetry. https://arxiv.org/abs/2404.14200

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