An explanation for the soft X-ray excess in AGN Jamie Crummy collaborators: Andy Fabian, Luigi Gallo, Randy Ross Suzaku Team Soft excess The soft excess is at a constant temperature over a large range in quasar characteristics, as shown by Walter and Fink (1993), Czerny et al. (2003), Gierliński and Done (2004), Porquet et al. (2004).... Our survey shows similar behaviour. Crummy et al. 2006 Gierliński & Done 2004 Analysis Fitting two models in xspec. We also model any extra cold absorbing continuum local to the source. Power law P.L. + black body Soft Excess P.L. + B.B. + absorption edges Warm Absorber P.L. + B.B. + edges + Gaussian Iron Emission Relativistically blurred photoionized disc Disc + edges Disc + edges + Gaussian Relativistically blurred photo- ionized disc model Degrees of freedom – not very many Inclination, inner radius, Illuminating Relativistic disc emissivity index * power law blurring Spectral index Laor, 1991 Warm Edge energies absorber? and depths, Narrow iron line energy and equivalent width line? Reprocessed radiation Ross & Fabian, (emission lines and Physically Output 2005 motivated Compton component) spectrum and self consistent Ionization parameter, iron abundance * may be zero Relativistically blurred photo- ionized disc model (part 2) * Reflection and power law Laor line = PG 1202+281 Relativistically blurred photo- ionized disc model fits MRK 586 Relativistically blurred photo- ionized disc model fits (part 2) PG 1501+106 Iron lines MCG –6-30-15 iron line from XMM (Vaughan and Fabian 2004) o i t a R “Broad relativistic lines were detected in three objects, less than 10% of the QSOs in the sample” - Jiménez-Bailón et al. 2005 Iron lines (part 2) MRK 586 (NAB 0205+02) from Gallo et al. 2004. Power law and black body model. Residuals consistent with a Laor iron line. Soft excess consistent with the iron line. Relativistically blurred photo- ionized disc model results Naturally explains “soft excess” and its constant ● temperature Explains some spectral features that could otherwise ● be interpreted as absorption edges Explains the apparent absence of broad iron lines in ● most quasars Explains all major spectral features of all quasars ● surveyed* * when you add necessary edges and cold iron lines to account for gas in the line ● of sight and a torus