AGNFITTER-RX: Modeling the radio-to-X-ray spectral energy distributions of AGNs

¹ European Southern Observatory (ESO), Karl-Schwarzschild-Straße 2, 85748 Garching bei München, Germany
e-mail: ltmartinez@uc.cl
² Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago, Chile
³ Millennium Institute of Astrophysics (MAS), Nuncio Monseñor Sótero Sanz 100, Providencia, Santiago, Chile
⁴ Max Planck Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
⁵ Dipartamento di Fisica e Astronomia, Universitá di Firenze, Via G. Sansone 1, 50019 Sesto Fiorentino, FI, Italy
⁶ INAF – Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
⁷ Max Planck Institute for Extragalactic Physics, Gießenbachstraße, 85741 Garching, Germany
⁸ School of Physics & Astronomy, Monash University, Clayton Campus VIC 3800, Australia
⁹ Escuela de Física – Universidad Industrial de Santander, 680002 Bucaramanga, Colombia
¹⁰ Instituto de Estudios Astrofísicos, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago 8320000, Chile
¹¹ Centre for Extragalactic Astronomy, Department of Physics, Durham University, South Road, Durham DH1 3LE, UK
¹² School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK
¹³ Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia
¹⁴ Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281-S9, Gent 9000, Belgium
¹⁵ Physics Department, Broida Hall, University of California, Santa Barbara, CA 93106-9530, USA
¹⁶ Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

Received: 24 January 2024
Accepted: 20 May 2024

Abstract

We present new advancements in the modeling of the spectral energy distributions (SEDs) of active galaxies by introducing the radio-to-X-ray fitting capabilities of the publicly available Bayesian code AGNFITTER. The new code release, called AGNFITTER-RX, models the broad-band photometry covering the radio, infrared (IR), optical, ultraviolet (UV), and X-ray bands consistently using a combination of theoretical and semi-empirical models of the active galactic nucleus (AGN) and host-galaxy emission. This framework enables the detailed characterization of four physical components of the active nuclei, namely the accretion disk, the hot dusty torus, the relativistic jets and core radio emission, and the hot corona, and can be used to model three components within the host galaxy: stellar populations, cold dust, and the radio emission from the star-forming regions. Applying AGNFITTER-RX to a diverse sample of 36 AGN SEDs at z ≲ 0.7 from the AGN SED ATLAS, we investigated and compared the performance of state-of-the-art torus and accretion disk emission models in terms of fit quality and inferred physical parameters. We find that clumpy torus models that include polar winds and semi-empirical accretion disk templates including emission-line features significantly increase the fit quality in 67% of the sources by reducing by 2σ fit residuals in the 1.5-5 μm and 0.7 μm regimes. We demonstrate that, by applying AGNFITTER-RX to photometric data, we are able to estimate the inclination and opening angles of the torus, consistent with spectroscopic classifications within the AGN unified model, as well as black hole masses congruent with virial estimates based on Hα. We investigate wavelength-dependent AGN fractions across the spectrum for Type 1 and Type 2 AGNs, finding dominant AGN fractions in radio, mid-infrared, and X-ray bands, which are in agreement with the findings from empirical methods for AGN selection. The wavelength coverage and the flexibility for the inclusion of state-of-the-art theoretical models make AGNFITTER-RX a unique tool for the further development of SED modeling for AGNs in present and future radio-to-X-ray galaxy surveys.