Evidence for a circumnuclear and ionized absorber in the X-ray obscured broad-line radio galaxy 3C 445

Abstract

Here we present the results of a Suzaku observation of the broad-line radio galaxy 3C 445. We confirm the results obtained with the previous X-ray observations which unveiled the presence of several soft X-ray emission lines and an overall X-ray emission which strongly resembles a typical type 2 Seyfert galaxy despite of the optical classification as an unobscured active galactic nucleus. The broad-band spectrum allowed us to measure for the first time the amount of reflection (R∼ 0.9) which together with the relatively strong neutral Fe Kα emission line (EW ∼ 100 eV) strongly supports a scenario where a Compton-thick mirror is present. The primary X-ray continuum is strongly obscured by an absorber with a column density of NH= 2–3 × 1023 cm−2. Two possible scenarios are proposed for the absorber: a neutral partial covering or a mildly ionized absorber with an ionization parameter logξ∼ 1.0 erg cm s−1. A comparison with the past and more recent X-ray observations of 3C 445 performed with XMM–Newton and Chandra is presented, which provided tentative evidence that the ionized and outflowing absorbers varied. We argue that the absorber is probably associated with an equatorial disc wind located within the parsec scale molecular torus.