The extreme properties of the nearby hyper-Eddington accreting active galactic nucleus in IRAS 04416+1215
A. Tortosa, Cláudio Ricci, Francesco Tombesi, Luis C. Ho, Pu Du, Kohei Inayoshi, Jian‐Min Wang, J. Shangguan, Ruancun Li
Abstract
The physical properties of the accretion flow and of the X-ray emitting plasma, in supermassive black holes accreting at extreme Eddington rates, are still very unclear. Here we present the analysis of simultaneous XMM-Newton and NuSTAR observations of the hyper-Eddington Seyfert 1 galaxy IRAS 04416+1215, carried out in 2020. The main goal of these observations is to investigate the properties of the X-ray corona, as well as the structure of the accretion flow and of the circumnuclear environment, in this regime of extreme accretion. IRAS 04416+1215 has one of the highest Eddington ratio (lambda(Edd) similar or equal to 472) in the local Universe. It shows an interesting spectral shape, very similar to the standard narrow-line Seyfert 1 galaxy's spectra, with the presence of multiphase absorption structure composed of three phases, whose estimate of the minimum and maximum distances suggests two different interpretations, one consistent with the three X-ray winds being cospatial, and possibly driven by magnetohydrodynamical processes, the other consistent with the multiphase winds being also multiscale. The X-ray spectrum of IRAS 04416+1215 also has a prominent soft excess component and a hard X-ray emission dominated by a reflection component. Moreover, our detailed spectral analysis shows that IRAS 04416+1215 has the lowest coronal temperature measured so far by NuSTAR (kT(e) = 3-22 keV, depending on the model). This is consistent with a hybrid coronal plasma, in which the primary continuum emission is driven by pair production due to high-energy tail of the energy distribution of non-thermal electrons.