The Hard X-Ray View of Reflection, Absorption, and the Disk-Jet Connection in the Radio-Loud AGN 3C 33

TL;DR

This study analyzes Suzaku and Swift data of radio galaxy 3C 33, revealing weak reflection features and exploring implications for accretion flow ionization and black hole spin orientation.

Contribution

It provides the first detailed X-ray spectral analysis of 3C 33, showing absence of typical reflection signatures and discussing possible reasons related to accretion and black hole spin.

Findings

No relativistic Fe Kα line detected

Upper limit on neutral reflection fraction R<0.41

Weak reflection features suggest highly ionized accretion flow or retrograde black hole spin

Abstract

We present results from Suzaku and Swift observations of the nearby radio galaxy 3C 33, and investigate the nature of absorption, reflection, and jet production in this source. We model the 0.5-100 keV nuclear continuum with a power law that is transmitted either through one or more layers of pc-scale neutral material, or through a modestly ionized pc-scale obscurer. The standard signatures of reflection from a neutral accretion disk are absent in 3C 33: there is no evidence of a relativistically blurred Fe K$\alpha$ emission line, and no Compton reflection hump above 10 keV. We find the upper limit to the neutral reflection fraction is R<0.41 for an e-folding energy of 1 GeV. We observe a narrow, neutral Fe K$\alpha$ line, which is likely to originate at least 2,000 R_s from the black hole. We show that the weakness of reflection features in 3C 33 is consistent with two interpretations: either the inner accretion flow is highly ionized, or the black-hole spin configuration is retrograde with respect to the accreting material.