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X-ray emission from narrow-line Seyfert 1 galaxies with extreme narrow broad line width Yanli Ai

X-ray emission from narrow-line Seyfert 1 galaxies with extreme narrow broad line width Yanli Ai Yunnan Astronomical Observatory Weimin Yuan ( Yunnan Astronomical Observatory ) Stefanie komossa ( Max Planck Institute for Extraterrestrial Physics ). Narrow Line Seyfert 1 (NLS1).

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X-ray emission from narrow-line Seyfert 1 galaxies with extreme narrow broad line width Yanli Ai

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  1. X-ray emission from narrow-line Seyfert 1 galaxies with extreme narrow broad line width Yanli Ai Yunnan Astronomical Observatory Weimin Yuan (Yunnan Astronomical Observatory) Stefanie komossa (Max Planck Institute for Extraterrestrial Physics)

  2. Narrow Line Seyfert 1 (NLS1) A special class of broad-line AGN • Some peculiar observed properties • softer X-ray spectra, rapid X-ray variability, strong optical FeII multiplets • Relatively small BH mass (e.g. Collin & Kawaguchi ’04) Accreting close to the Eddington rate L/LEdd~1 possible via slim disk, c.f. standard disk (e.g. Abramowicz + ‘88; Wang J.-M. + ‘99, Mineshige + ’00) Balmer lines broader than forbidden lines (observable BLR) but narrower than normal type I AGN (fwhm < 2000km/s)

  3. Zhou et al. 2006 selected ~ 2000 NLS1s from SDSS Break down at ~ 1000 km/s Motivation : Γ - FWHM (Hβ) anti-correlation important in AGN correlation space (Eigenvector 1 ) ROSAT photon index X-ray properties of these NSL1s with extreme narrow Balmer line width is interesting ! Soft X-ray excess emission NLS1s + Sy1s Zhou et al . 2006 Estimated from hardness ratio Uncertainty : spectral model assumption intrinsic absorption Boller et al .1996 Detailed X-ray analysis needed !

  4. Soft X-ray excess emission (SXE) Steeper Soft X-ray spectrum is caused by stronger soft excess emissionobserved kT > maximum standard accretion disk KT Cannot be explained by the thermal emission from the standard accretion diskquestion: where does SXE come from? Crummy et al. 2006

  5. Viable models of SXE from Done + 2007 Comptonization kT~0.1-0.2keV tau~20 reflection (scattering) Ionized disk Absorption by optically thin gas Czerny & Elvis ‘87, Wandel & Petrosian ‘88, Shimura & Takahara ‘95 Ross & Fabian’05, Crummy + ’06 Done + et al. ‘06 Atomic opacity in E~0.7-3keV OVII/VIII, Fe L-shell absorption edges

  6. Sample selection1) FWHM (Hβ) < 1200km/s from 2,000 NLS1s in Zhou et al (2006)2) matched with ROSAT PSPC and 2XMM with radius of 30" and 5" respectively.3) requiring X-ray counts > 200 for spectral analysisconsist of 20 NLS1s, having 12 observations in XMM and 13 in ROSATProperties :1) typical NLS1s in optical 2) small balck hole masses (three IMBH candidates in Greene & Ho, 2004)3) high Eddington ratio4) all are radio-quiet except SDSS J1633+4718 with radio loudness of 2.13

  7. In 0.2-10.0 KeV eight NLS1s have enough photons for X-ray spectral analysis soft excess exist for all of them

  8. Result of soft X-ray spectral fittingstrong intrinsic absorption have not been detectedOur result confirm the break down of Γ - FWHM(Hβ) relation in Zhou et al. (2006)

  9. Soft excess temperature distribution1) higher than expected maximum standard accretion disc temperature2) in 100 - 200 eV, similar to that in much more massive PG quasar

  10. Soft X-ray excess strength distributionsoft excess strength does not increase with decrease of line width .possible explanation for break down : soft excess saturates at FWHM around 1000 km/s

  11. Summary of soft X-ray excess spectral fitting • Soft X-ray excess is almost ubiquitous and prominent • Additional emission component models • blackbody or BB (always fit but NOT necessarily the best) • Comptonization • Disk reflection • required for several other objects • dominate direct emission, large reflection fraction>>1 • absorption • no good fit, also by variability • Sometimes a partially ionized thin absorber is required (but not strong enough, not blurred) either an additional emission component or disk reflection dominated

  12. Example: SDSS J0940+0324 Compton scattering XMM PN XMM MOS 0.34 KeV Γ=1.99 chi^2 = 274.4 (273dof)

  13. Example: SDSS J2299+0107 Blurred disk refl. Power-law + BB XMM PN XMM PN R_in=2.2Rg extreme ! chi^2=278(290 d.o.f) kT=0.13KeV Γ=2.7 chi^2 = 293 (293 d.o.f.)

  14. Summary 1). In spectral analysis of 20 NSL1s we confirmed our result in Zhou et al. (2006) that soft X-ray photon indices and the broad optical emission line widths break down at FWHM (Hβ) around 1000km/s. saturation of the relative strength of soft excesss at narrow line width as one possible explanation. 2). thermal temperature of excess in 100 - 200eV, quite same with much more massive radio-quiet QSOs. Significantly higher than the maximum accretion disk temperature 3). SXE may have different origins. Comptonization can reproduce soft excess feature in five NLS1s with relatively low Eddington ratio ( < 0.5); blurred ionized disc reflection model well reproduce the XMM spectra in three NLS1s with high Edd. ratio. Our result suggest the origin may be dependent on Edd. Ratio ( ~ 1.0 )

  15. Thank you

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