The history of the iron K_αline profile in the Piccinotti AGN ESO 198-G24

Abstract

Abstract. This paper presents ASCA (July 1997), XMM-Newton (December 2000) and BeppoSAX (January 2001) observations of the Piccinotti Seyfert 1 galaxy ESO 198-G24. The BeppoSAX 0.1-200 keV spectrum exhibits reprocessing features, probably produced by an X-ray illuminated, relativistic accretion disk subtending a solid angle < ∼ 2π. During the XMMNewton observation the fluorescent iron K α line profile (centroid energy E c 6.4 keV) was broad and twice as bright as in the BeppoSAX observation. An additional emission feature (E c 5.7 keV), detected at the 96.3% confidence level, may be part of a relativistic, double-peaked profile. By contrast, in the earlier ASCA observation the line profile is dominated by a remarkably narrow "core" (intrinsic width, σ < 50 eV). If this component is produced by reflection off the inner surface of a molecular torus, its large Equivalent Width ( 300 eV) most likely represents the "echo" of a previously brighter flux state, in agreement with the dynamical range covered by the historical X-ray light curve in ESO 198-G24.

XMM-Newton observation of the Seyfert 1 ESO 198-G24

“…It is consistent with the value found during the previous XMM-Newton observation in December 2000 (i.e., 1.09 ± 0.01 × 10 −11 erg cm Guainazzi 2003). There is still a clear positive deviation near 6.4 keV (in the rest-frame), with this power-law model with Γ ∼ 1.77 (which is the same index value as found in the 2−5 keV energy range, see Fig.…”

“…= 681.3/713). This photon index value is entirely consistent with those found by Guainazzi (2003) Figure 1 displays the data to model ratio extrapolated over the 0.3-10 keV broad band energy. A significant positive residual is clearly seen below 1.5−2 keV, both in MOS and PN data.…”

4U 1344-60: a bright intermediate Seyfert galaxy atz= 0.012 with a relativistic Fe K$\mathsf{\alpha}$ emission line

“…Turner et al 2002;Guainazzi 2003;Porquet et al 2004;Turner et al 2004;Della Ceca et al 2005). We found two examples of these features in the XMM-Newton spectrum of 4U 1344−60 at 4.90 ± 0.04 (at 95.5% c.l.)…”

Light bending models in AGNs

“…As discussed, an early example was found in the ASCA observation of MCG-6-30-15 in 1997, which was interpreted as Fe K emission induced from a localised region of the disc, possibly due to illumination by a flare above it (Iwasawa et al 1999). More examples followed in recent years thanks to the higher sensitivity of XMM-Newton and Chandra X-ray Observatory (Turner et al 2002;Guainazzi et al 2003;Yaqoob et al 2003;Petrucci et al 2002;Turner Kraemer & Reeves 2004;Bianchi et al 2004;Longinotti et al 2004;Porquet et al 2004;Turner et al 2006;. These features can be attributed to an Fe Kα line arising from relatively localised reflecting spots on the accretion disc (Iwasawa et al 1999;Ruszkowski 2000;Nayakshin & Kazanas 2001;Dovčiak et al 2004).…”