Nuclear obscuration structure in Mrk 417 based on NuSTAR and Swift/BAT data

TL;DR

This study analyzes the X-ray spectrum of Seyfert galaxy Mrk 417 using NuSTAR and Swift/BAT data, revealing details about its obscuring structure, including a ring-like geometry of the torus.

Contribution

It provides the first detailed physical modeling of Mrk 417's obscuring torus using NuSTAR and Swift/BAT data with complex models like MYTorus and BNTorus.

Findings

Obscuring column density is approximately 3.2 x 10^{23} cm^{-2}

Gas-dust torus covering factor estimated at 0.29-0.34

X-ray luminosity in 2-10 keV is about 3.16 x 10^{43} erg/s

Abstract

We present the results of X-ray spectral analysis of the Seyfert type 2 galaxy Mrk 417 observed by the NuSTAR (3-60 keV) and the Swift/BAT (14-150) observatories. The NuSTAR data shows a good fit with a baseline model which composed of an absorbed cutoff power-law component and reflected emission from the cold neutral medium. We found that the spectrum is steep $\Gamma = 1.63_{-0.11}^{+0.10}$ and obscured by hydrogen column density of $N_{H} = 3.22_{-0.39}^{+0.41} \cdot 10^{23} cm^{-2}$, narrow $FeK_\alpha$ emission line has an equivalent width of $EW = 115_{-1}^{+2}$ eV that suggests this feature is originated in a moderate density of obscurer. In combining NuSTAR data with Swift/BAT spectrum we also applied a more physically motivated approach using complex physical models MYTorus and BNTorus. For the first case the photon index of $\Gamma_{MYTorus} = 1.68_{-0.09}^{+0.09}$ and the line-of-sight column density of the absorber $N_{H,l.o.s} = 3.36_{-0.07}^{+0.04} \cdot 10^{23} cm^{-2}$. Applying BNTorus model shows the photon index $\Gamma_{BNTorus} = 1.75_{-0.09}^{+0.09}$ and absorption $N_{H,l.o.s} = 3.72_{-0.39}^{+0.49} \cdot 10^{23} cm^{-2}$. Based on the results we get an estimation of gas-dust torus covering factor $f_{c} = 0.29-0.34$ and an intrinsic X-ray luminosity in 2-10 keV of $\approx 3.16\cdot 10^{43}$ erg/s. Further analysis of Mid-Infrared (MIR) observational data, indicates that the covering factor maybe even smaller $f_{c} \approx 0.12$. Our results allow us to suggest that obscuring material of Mrk 417 has preferably a ring-like geometry.