Unobscured radio-quiet Active Galactic Nuclei under the eyes of IXPE

TL;DR

This study uses IXPE, XMM-Newton, and NuSTAR to analyze X-ray polarization in unobscured radio-quiet AGN, revealing polarization aligned with radio jets and insights into coronal geometry.

Contribution

It provides the first X-ray polarization measurements for these AGN, constraining coronal geometry and jet alignment with new observational data.

Findings

Significant polarization detected in NGC 4151 and IC 4329A.

Polarization angles aligned with radio jets.

Monte Carlo simulations favor a radially extended corona.

Abstract

We present the results of the X-ray polarimetric analyses performed on unobscured radio-quiet Active Galactic Nuclei (AGN) with the Imaging X-ray Polarimetry Explorer (IXPE), with simultaneous XMM-Newton and NuSTAR data. The synergy of these instruments is crucial to constrain the X-ray corona physical properties and assess its geometry. In the first two years of operation, three AGN have been observed: significant polarization was detected for NGC 4151 (4.9$\pm$1.1 per cent) and IC 4329A (albeit with less confidence, 3.3$\pm$1.1 per cent), with polarization angles aligned with their radio jets, while only an upper limit was found for MCG-05-23-16 ($<$3.2 per cent). Monte Carlo simulations, conducted to investigate the coronal geometry of these AGN, favor a radially extended corona geometry in NGC 4151 and IC 4329A, a scenario consistent also with MCG-05-23-16, if the disk inclination angle is below 50$^\circ$.