Weimin YuanYunnan Observatory/NAOC, CAS, Kunming, China
Systematic study of a large sample of Systematic study of a large sample of NLS1 galaxies from SDSS NLS1 galaxies from SDSS
—— first results first results
H. Zhou, T.-G. Wang, H. Lu, X. Dong J. Wang, Y. LuUniversity of Science & Technology of China
Hefei
H. Zhou, T.-G. Wang, W. Yuan, et al. 2006, ApJS, 166, 128
Narrow Line Seyfert 1 galaxiesNarrow 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/LEdd 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, MBH - 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 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
NLS1 sample from the SDSS DR3NLS1 sample from the SDSS DR3
The sample was drawn from ~387,483 galaxies and QSO in the SDSS DR3 (z<0.8)
Selection criteria: Hα or Hβ detected at >10 σ significance level FWHM < 2200 km/s
The sample: 2011 NLS1
1885 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)
<5% in very radio-loud AGN (R>2)
The FeII emission in NLS1s is ~twice stronger than normal BL AGN
notenote
The conventional NLS1 definition mayThe conventional NLS1 definition may
include some AGNs with IMBH mass include some AGNs with IMBH mass
Objects with MObjects with MBHBH <~ 10 <~ 1066 M⊙ M⊙
See poster # 268 for our IMBH See poster # 268 for our IMBH ((<~ 10<~ 1066 M⊙ M⊙ )) AGN sample AGN sample
Line EW – luminosity relation --- (inverse) Baldwin effect
Hβluminosity λL 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)
RO
SA
T p
hoto
n
ind
ex
RO
SA
T p
hoto
n
ind
ex
Black hole mass – Black hole mass – stellar velocity dispersion relationstellar velocity dispersion relation
MBH: estimated from line-width and luminosity (e.g. kaspi et al. 2000, Mclure & Jarvis 2002, Dietrich & Hamann)
σσ: : measured from fitting the nuclear starlight spectra of host galaxies by the galaxy-nuclear spectral decomposition algorithm stellar velocity dispersion (km/s)(km/s)
Bla
ck h
ole
mas
s (M
⊙)
Trai
mai
ne e
tal.
2002
Black hole mass – Black hole mass – stellar velocity dispersion relationstellar velocity dispersion relation
stellar velocity dispersion (km/s)(km/s)
Bla
ck h
ole
mas
s (M
⊙)
Possible contamination of σσ 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
Trai
mai
ne e
tal.
2002
e.g. Mathur et al. 2001, Grupe & Mathur 2004, Biao & Zhao 2004, , Botte et al. 2004,
Wang & Lu, Wandel 2002, 2004, ……)
summarysummary
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 workCurrent 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 XMM-Newton spectral fitsspectral 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
Results of spectral fits for the XMM sub-sample with Results of spectral fits for the XMM sub-sample with enough photon counts (~30 objects)enough photon counts (~30 objects)
L. Fan, et al. in prep..
distribution of the photon index of the distribution of the photon index of the underlying power-lawunderlying power-law
Current work and future planCurrent 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 J0324+3410
SDSS spectrum: typical of NLS1
HST residual image
one-armed spiral
A NLS1-blazar composite SDSS J0324+3410
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 blazarZhou, Wang, Yuan et al. 2006 ApJL submitted
AGN with IMBH in the dwarf galaxy J1605+1748AGN with IMBH in the dwarf galaxy J1605+1748
MMBHBH~ 6 x10~ 6 x104 4 MM ⊙ ⊙ (Kaspi et al. 2005) (Kaspi et al. 2005)
2.5 x102.5 x105 5 MM ⊙ ⊙ (Bentz et al.2006) (Bentz et al.2006)
Dong, Wang, Yuan, et al., ApJ submitted, astro-ph/0610145
poster # 268poster # 268
host galaxy Mhost galaxy MRR~ -17.8~ -17.8
IMBH in the dwarf galaxy J1605+1748IMBH in the dwarf galaxy J1605+1748
NLS1s from SDSSNLS1s from SDSS(3) Frequency of finding NLS1s: (3) Frequency of finding NLS1s:
strongly dependent on optical luminositystrongly dependent on optical luminosity
The Fe II emission strength
The FeII emission in NLS1s is ~twice stronger than normal BL AGN
R4570 = Fe II (λ4434-4684) / Hβ