Weighing black holes in radi

o-loud AGNs

Xue-Bing Wu ( 吳學兵 )

(Dept. of Astronomy, Peking Univ.)

wuxb@bac.pku.edu.cn

Collaborators: Ran Wang, F.K. Liu (PKU); M.Z. Kong, J.L. Han (NAOC)

Content

IntroductionBH mass from the BLR size -

emission line luminosity relationBH mass from the fundamental plane

relation of AGN elliptical hostsSummary

1. Introduction

Most AGNs in Reverberation mapping studies are radio quiet. Can the R-L relation be applied to (extremely) radio-loud AGNs?

For blazar-type AGNs, the emission line is weak/absent. How to estimate the BH mass of them?

BLR Scaling with LuminosityBLR Scaling with Luminosity

2HH

24

)H(

rn

L

cnr

QU

r L0.6±0.1

R-L relation from reverberation mapping

r L1/2

With the R-L relation, we can estimate the BLR size from the optical continuum luminosity

R-L relation from photoionization model

(Kaspi et al. 2000, 2005)(Kaspi et al. 2000, 2005)

SMBH and Galactic Bulge

• Relations of black hole mass with bulge luminosity and central velocity dispersion (for normal galaxies & AGNs)

Ferrarese et al. (2001)

AGN

With the M-σ relation, we can estimate the BH mass from the stellar velocity dispersion

2. BH Mass from the R-LBH Mass from the R-LHH relation relation

(Wu, Wang, Kong, Liu & Han 2004, A&A, 424, 793)(Wu, Wang, Kong, Liu & Han 2004, A&A, 424, 793)

• BLR sizes are usually derived from an empirical relation R L5100A

0.7(Kaspi et al. 2000, 2005).

• Optical jets of some AGNs have been observed by the HST (Scarpa et al. 1999; Jester 2003; Parma et al. 2003). Optical Synchrotron radiations have been found in some RL AGNs (Whiting et al. 2001; Chiaberge et al. 2002; Cheung et al. 2003)

• For RL AGNs, optical continuum luminosity may be significantly contributed from jets, and may not be a good indicator of ionizing luminosity• It may be better to use the relation between the emission line luminosity and the BLR size

•Using the R-L5100A relation one can overestimate MBH for extremely radio-loud quasars; using thethe R-LR-LHH relation relation may be more accurate.

Recently we also extend such a study to UV broad emission lines

(Mg II & CIV) (Kong, Wu, Wang, & Han, 2006, ChJAA, 6, 396)

BH mass of a blazar AO 0235+164(Liu, Zhao & Wu, 2006, ApJ, 650, 749)

R-L5100A relation: 1.5 x 109 M

R-LR-LHH relation: relation: 5.8 x 108 M

=FWHM[OII]/2.35 & M-σ relation: 3.6 x 108 M

The result from the R-L5100A relation is overestimated

->BH mass of AO 0235+164: 4.7 x 108 M

•Reverberation mapping can not apply to BL Lacs; OReverberation mapping can not apply to BL Lacs; Only a dozen of BL Lacs have measured nly a dozen of BL Lacs have measured values (Falo values (Falomo et al. 2002; Barth et al. 2002)mo et al. 2002; Barth et al. 2002)•Host galaxies of BL Lacs are ellipticals (Urry et al. 2Host galaxies of BL Lacs are ellipticals (Urry et al. 2000)000) values can be derived from the values can be derived from the fundamental planfundamental planee of ellipticals of ellipticals

(Bettoni et al. 2001)

3. BH Mass from the fundamental plane of AGN 3. BH Mass from the fundamental plane of AGN elliptical hostselliptical hosts

(Wu, Liu & Zhang, 2002, A&A, 389, 742)(Wu, Liu & Zhang, 2002, A&A, 389, 742)

BH Mass from the fundamental plane of AGN elliptBH Mass from the fundamental plane of AGN elliptical hostsical hosts

• SMBH masses could be estimated for BL Lacs and SMBH masses could be estimated for BL Lacs and other AGNs with high-quality HST imagesother AGNs with high-quality HST images

Comparison of Eddington ratios of AGNsComparison of Eddington ratios of AGNs

The Eddington ratios (dimensionless accretion rates) of radio galaxies are about two orders lower than those of quasars.

The host galaxy was marginally resolved of re=0.72’’ and R-band absolute magnitude MR= -23.23 (Heidt et al. 1999)

Using the BH mass – bulge luminosity relation (McLure & Dunlop 2002),

It gives MBH=4.6E8 solar masses.

Using the fundamental plane of elliptical hosts and the MMBHBH - - relation,

It gives MBH=3.2E8 solar masses. MBH~4E8 solar masses

Support the new binary BH model (Valtaoja et al 2000)

Primary black hole mass of OJ 287 (Liu & Wu, 2002, A&A, 388, L48)

4. Summary

•BH mass of AGNs can be obtained by reverberation mapping, the MMBHBH - - relation and the R-L relation.

• For (extremely) radio-loud AGNs, using the R-L5100A relation may overestimate the BH mass. Thehe RRBLRBLR -emi -emi

ssion line luminosity relation ssion line luminosity relation is more preferable.

• For blazar-type AGNs with weak/no emission lines, we can estimate the BH mass from the fundamental plthe fundamental plane of their elliptical hostsane of their elliptical hosts and the MMBHBH - - relation

•These methods can be applied to high-z quasars