Weimin Yuan Yunnan Observatory/NAOC, CAS, Kunming, China Systematic study of a large sample of NLS1 galaxies from SDSS — first results H. Zhou, T.-G. Wang, H. Lu, X. Dong J. Wang, Y. Lu University of Science & Technology of China Hefei H. Zhou, T.-G. Wang, W. Yuan, et al. 2006, ApJS, 166, 128

Narrow Line Seyfert 1 galaxies narrow Balmer lines FWHM(Hβ)<2000km/s [OIII]/ Hβ small (<3) strong FeII soft X-ray: steep spectrum, rapid variability outflows ([OIII] and CIV) … ) extreme region in the eigenvector 1 space  small BH mass and high L/L Edd useful to constrain AGN models

Controversial and unexplored issues ~ 400 NLS1s known before our sample (incl. e.g., the SDSS EDR NLS1 sample of ~150, Williams et al. 2002) broad band SED black hole mass determination, M BH - sigma relation NLS1s with flat soft X-ray spectra [OIII] strength, NLR, outflows host galaxies type 2 counterparts optical variability radio-loud NLS1, radio-emission, jets? accretion models evolution  A larger and homogeneous NLS1 sample is needed

Analysis of SDSS spectra Search from SDSS spectroscopic targets as galaxies and QSO Spectral decomposition of host galaxy starlight and nuclear (continuum + emission lines), using our EL-ICA algorithm (Ensemble Learning – Independent Component Analysis) Using 6 IC synthesized galaxy templates built up from the SSP spectral library of Bruzual & Charlot 2003 Lu et al. 2006, AJ, 131, 790  stellar V dispersion also obtained

Spectral line fitting broad and narrow line de-blending Hαregion Hβregion

NLS1 sample from the SDSS DR3 The sample was drawn from ~387,483 galaxies and QSO in the SDSS DR3 (z<0.8) Selection criteria: H α or Hβ detected at >10 σ significance level FWHM < 2200 km/s The sample: 2011 NLS NLS1 ( FWHM<2000 km/s) <7% have radio detection (c.f. 10% for BL AGN) NLS1 fraction: 15% in radio-quiet & radio-intermediate AGN (R<1) 10% in moderate radio-loud AGN (1<R<2) 2) The FeII emission in NLS1s is ~twice stronger than normal BL AGN

note The conventional NLS1 definition may include some AGNs with IMBH mass Objects with M BH <~ 10 6 M ⊙ See poster # 268 for our IMBH ( <~ 10 6 M ⊙ ) AGN sample

Line EW – luminosity relation --- (inverse) Baldwin effect HβluminosityλL λ luminosity at 5100Ǻ EW Hβ EW FeII

Soft X-ray Slope vs. FWHM (Balmer) Turnover line-width ~ 1000km/s FWHM Hβ(km/s)FWHM Hα(km/s) ROSAT photon index

Narrow line region No difference between NLS1 and normal BL AGN

Black hole mass – stellar velocity dispersion relation M BH : estimated from line- width and luminosity (e.g. kaspi et al. 2000, Mclure & Jarvis 2002, Dietrich & Hamann) σ: σ: measured from fitting the nuclear starlight spectra of host galaxies by the galaxy-nuclear spectral decomposition algorithm (km/s) stellar velocity dispersion (km/s) Black hole mass (M ⊙ ) Traimaine etal. 2002

Black hole mass – stellar velocity dispersion relation (km/s) stellar velocity dispersion (km/s) Black hole mass (M ⊙ ) σ Possible contamination of σ by the rotation galactic disk? Use only nearby galaxies with face- on disks or their SDSS fiber aperture 3” dominated by galactic bulges NLS1 are underage AGN in which the growth of the SMBH lags the formation of the bulge Traimaine etal e.g. Mathur et al. 2001, Grupe & Mathur 2004, Biao & Zhao 2004,, Botte et al. 2004, Wang & Lu, Wandel 2002, 2004, ……)

summary Providing to the AGN community with the largest NLS1 sample The frequency of finding NLS1s depends strongly on optical luminosity and radio-loudness Turnover of the trend of soft X-ray Slope vs. FWHM (Balmer) Inverse Baldwin effect seen in Hbeta and FeII NLR in NLS1s is not different from that of BLS1s  finding NLS2 is challenging NLS1s are underage AGN in which the growth of the SMBH lags the formation of the bulge

Current work Search for optical variability ~150 covered in the SDSS SN survey (preliminary results see poster #280 Y. Ai et al.) optical monitoring X-ray data analysis (XMM, ROSAT, etc.) a sample of ~40 objects with XMM data

XMM-Newton spectral fits one power law: 10/22 PL + soft x-ray excess: 12/22 No significant Fe K line Other models, e.g. p-free model (S. Mineshige’s talk) one power law Broken power law

Example of spectral fits to XMM data. L. Fan, et al. in prep.

Results of spectral fits for the XMM sub-sample with enough photon counts (~30 objects). L. Fan, et al. in prep.

distribution of the photon index of the underlying power-law

Current work and future plan much detailed statistical analysis Fraction of NLS1 w.r.t. luminosity, z, etc. …… broad band properties and SED UV (Galex) Host galaxy morphology and stellar contents new radio/X-ray observations photometric/spectroscopic monitor, variability study possible black hole mass measurement by reverberation mapping Cosmic evolution: NLS1 sample at higher redshifts using the MgII line

A NLS1-blazar composite J SDSS spectrum: typical of NLS1 HST residual image one-armed spiral

A NLS1-blazar composite SDSS J Non-thermal continuum SED resembles Mrk 421 TeV γ-ray detected (3 σ) by Whipple (Falcone 0’4) Intra-night large amplitude variability X-ray fast variability seen by Swift myth ? NLS1: high accretion rate HPB: low accretion rate HPB blazar Zhou, Wang, Yuan et al ApJL submitted

AGN with IMBH in the dwarf galaxy J M BH ~ 6 x10 4 M ⊙ (Kaspi et al. 2005) 2.5 x10 5 M ⊙ (Bentz et al.2006) Dong, Wang, Yuan, et al., ApJ submitted, astro-ph/ poster # 268

host galaxy M R ~ IMBH in the dwarf galaxy J

NLS1 sample: outline The sample BLR NLR Black hole – bulge relation summary & future works

NLS1 sample from the SDSS DR3 The sample was drawn from ~387,483 “galaxies”/”QSO” in the SDSS DR3 (z<0.8) Decomposition of Starlight spectrum and Nuclear emission (continuum + emission lines) starlight component modeled by the 6 Independent Components (ICs); Un-reddened nuclear continuum; optical FeII template (width fixed to that of broad component of Hα); template of high-n Balmer emission lines (10≤n ≤ 50) and Balmer continuum; the extinction of the host galaxy and the nuleus; Emission-Line Fitting: Gaussian/Lorentzian

NLS1s from SDSS (3) Frequency of finding NLS1s: strongly dependent on optical luminosity

The Fe II emission strength The FeII emission in NLS1s is ~twice stronger than normal BL AGN R 4570 = Fe II (λ ) / Hβ

Radio-loudness

NLS1 host galaxies: mostly early type galaxies