Broad-Band X-ray Variability of AGNs with Suzaku Y. Terashima Ehime Univ. and The Suzaku SWG team

Outline The Suzaku Satellite Broad band X-ray spectral variability in –MCG –MCG –NGC 4051

The Suzaku Satellite Japan-US X-ray Observatory Launched on July 10, 2005

The Suzaku Satellite Japan-US X-ray Observatory Launched on July 10, 2005 Named after legendary red bird Suzaku in Chinese myth

The Four Guardians in Chinese Myth Red Bird - Suzaku 朱雀 [South] White Tiger 白虎 [West] Blue Dragon 青龍 [East] Black Turtle 玄武 [North] Infrared Images of inner walls of ancient tomb in Asuka, Japan © National Research Institute for Cultural Properties

The Suzaku Satellite Broad band coverage Low background / High sensitivity at High E Detection of faint hard sources or highly absorbed sources Spectral variability on short time scales A powerful new tool to study the central engine of AGNs AO-2 deadline Dec.1 see Energy (keV) NGC 2110 Okajima et al. X-ray Imaging Spectrometer (CCD) Hard X-ray Detector

X-ray Spectral Components and Variability in AGNs AGN spectral components - Compton refelection, Fe-K line etc. Hard X-ray (>10 keV) essential for unambiguous interpretation of continuum and broad Fe line X-ray Variability Complex spectral variability steeper slope at higher flux Intrinsic changes l.o.s. absorption? multiple component ｓ ? Time resolved spectroscopy with Suzaku X-ray source reflection

(1) MCG Miniutti, Fabian et al. 2006, PASJ in press(astro-ph/ ) Constant Reflection hump Suzaku lightcurve Factor >3 variability PL + Strong Fe-K line and reflection hump Broad Fe-K line from Kerr BH? Smaller amplitude at higher E High flux Low flux Net 300 ksec

MCG High - Low Difference Spectrum Pure power law (  =2.2) Fe line and reflection hump appear constant. Broad line only mildly varied. Light bending effect around a Kerr BH? (Miniutti & Fabian 2004) Energy (keV) Direct spectral fits to variable component

(2) MCG Reeves et al. 2006, PASJ, in press High flux = Red; Low flux = Blue; Reflection:Black Continuum varied by ~40% over 220 ks duration PL + Fe line + reflection i=53 +7/-9 deg Rin = /-10 Rg  =1.9 power law Fe line reflection Narrow(  <50 eV) + Diskline fit

MCG High - Low Difference Spectrum Variable component: pure power law (  =1.9) modified by absorption Fe line and reflection hump ~ constant Two component model var. PL + cont reflection

x10 5 (s) Time (s) keV Net 86 ksec (3) NGC 4051 Terashima et al. in prep. 1/2-1/3 of historical average 9x ergs s -1 Factor x7-8 flares  =2 PL reflection Smaller amplitude at higher E Similar spec. PL + Fe + reflection C/ S

NGC 4051 Difference Spectrum  = /-0.1 Variable power law  ~2.1 Constant Fe+reflection Two comp. model Const. narrow Fe line (  <50 eV), sharp Fe-K edge: Consistent w/ reprocessing & reverberation by distant matter Variable absorption at <3 keV

NGC 4051 in 2002 Very low flux state with XMM-Newton ~1/2 of Suzaku flux Highly absorbed component disappeared at the lowest flux state. Presence of additional absorbed PL or variabiltiy of absorption column Difference (Green - Blue) NH = 1.5x10 23 cm Energy (keV) Haba et al. in prep.

Summary Suzaku - new powerful observatory to study AGNs AO-2 due Dec. 1 ( ``Two component’’ behavior common Variable PL - vicinity of BH Constant Fe line + reflection hump - G.R. effect or distant matter Time dependent absorption in NGC 4051 Future: Mechanism of intrinsic variability G.R. effect, energy release process Nature of variable absorber - physics of ``torus’’ / ionized absorber

NGC 4051