Physical Parameters of the Torus for the Type 2 Seyfert IC 5063 from Mid-IR and X-Ray Simultaneous Spectral Fitting

Esparza-Arredondo, Donaji; González-Martín, Omaira; Dultzin, Deborah; Ramos Almeida, Cristina; Fritz, Jacopo; Masegosa, Josefa; Pasetto, Alice; Martínez-Paredes, Mariela; Osorio-Clavijo, Natalia; Victoria-Ceballos, Cesar
Bibliographical reference

The Astrophysical Journal

Advertised on:
12
2019
Number of authors
10
IAC number of authors
1
Citations
9
Refereed citations
9
Description
In order to understand the diversity of classes observed in active galactic nuclei (AGNs), a geometrically and optically thick torus of gas and dust is required to obscure the central engine depending on the line of sight to the observer. We perform a simultaneous fitting of X-ray and mid-infrared (mid-IR) spectra to investigate whether the same structure could produce both emissions and, if this the case, to obtain better constraints for the physical parameters of the torus. In this case we take advantage of the fact that both emissions show important signatures of obscuration. We used the nearby type 2 active nucleus IC 5063 as a test object. This object is ideal because of the wealth of archival data, including some high-resolution data. It also has a relatively high AGN luminosity that dominates at both X-ray and mid-IR frequencies. We use high spectral resolution NuSTAR and Spitzer/IRS spectra. The AGN dusty models used several physically motivated models. We found that the combination of the smooth torus models at mid-IR by Fritz et al. and at X-rays by Baloković et al., with the viewing and half-opening angles linked to the same value, is the best choice to fit the spectra at both wavelengths. This allows us to determine all the parameters of its torus. This result suggests that the structure producing the continuum emission at mid-IR and the reflection component at X-ray is the same. Therefore, we prove that this technique can be used to infer the physical properties of the torus, at least when AGN dust dominates the mid-IR emission and the reflection component is significant at X-rays.
Related projects
Supermassive black holes modify the distribution of molecular gas in the central regions of galaxies. Credit: HST and C. Ramos Almeida.
Nuclear Activity in Galaxies: a 3D Perspective from the Nucleus to the Outskirts

This project consists of two main research lines. First, the study of quasar-driven outflows in luminous and nearby obscured active galactic nuclei (AGN) and the impact that they have on their massive host galaxies (AGN feedback). To do so, we have obtained Gran Telescopio CANARIAS (GTC) infrared and optical observations with the instruments

Cristina
Ramos Almeida