1. The redshift dependence of the MBH-Mhost relation in quasars
Max-Planck Institut fuer Astronomie Università degli Studi dell’Insubria
Roberto Decarli
The redshift dependence of the MBH-Mhost relation in quasars
A. Treves R. Falomo M. Labita
J.K. Kotilainen R. Scarpa M. Uslenghi
Decarli et al., 2010a-b, MNRAS 402, 2441 & 2453
AGN9 Ferrara - May, 26, 2010

2. MBH – host galaxy relations
Gultekin et al. (2009)

3. MBH – host galaxy relations
Black holes
BLR
Host galaxies
Rinf = G MBH / s*2 ~ Rhost
Gultekin et al. (2009)

4. MBH – host galaxy relations
Black holes
BLR
Host galaxies
Rinf = G MBH / s*2 ~ Rhost ? ? ?
Gultekin et al. (2009)

5. Our study
96 quasars (48 RQQs, 48 RLQs) with 0<z<3 (2x the sample by Peng et al., 2006 and 3x McLure et al., 2006)
Host galaxy luminosity from high res. images
Black hole masses from spectra

6. Our study
96 quasars (48 RQQs, 48 RLQs) with 0<z<3 (2x the sample by Peng et al., 2006 and 3x McLure et al., 2006)
Host galaxy luminosity from high res. images
Black hole masses from spectra
For low-z quasars, images in the HST-WFPC2, spectra from the SDSS and HST-FOS and from on- purpose observations at the Asiago 1.82m Telescope.
For z>0.5 targets, images taken at the NOT and the ESO/VLT, spectra from the NOT and ESO/3.6m Telescope.

7. Virial estimate of MBH MBH = G-1 RBLR vBLR2
RBLR ~ lLla (Kaspi et al., 2000, 2005, 2007)
vBLR = f FWHM

8. Virial estimate of MBH MBH = G-1 RBLR vBLR2
RBLR ~ lLla (Kaspi et al., 2000, 2005, 2007)
vBLR = f FWHM

10. QSO
PSF

11. QSO
PSF

12. QSO
PSF

13. QSO
PSF

14. QSO
PSF

15. The MBH–Mhost ratio as a function of z
G ≡ MBH/Mhost increases of a factor ~7 from z=0 to z=3
log G = (0.28 ± 0.06) z (2.91 ± 0.08)
Decarli et al (2010 a,b)

16. The MBH–Mhost ratio as a function of z
G ≡ MBH/Mhost increases of a factor ~7 from z=0 to z=3
log G = (0.28 ± 0.06) z (2.91 ± 0.08)
Decarli et al (2010 a,b)

17. The MBH–Mhost ratio as a function of z
G ≡ MBH/Mhost increases of a factor ~7 from z=0 to z=3
log G = (0.28 ± 0.06) z (2.91 ± 0.08)
Decarli et al (2009 a,b)

18. Unresolved hosts / disk contaminations
Decarli et al (2010 a,b)

19. Unresolved hosts / disk contaminations
Decarli et al (2010 a,b)

20. Different SFHs
Decarli et al (2009 a,b)

21. Different SFHs G ≡ MBH/Mhost increases of a factor ~7 from z=0 to z=3
log G = (0.28 ± 0.06) z (2.91 ± 0.08)
Decarli et al (2009 a,b)

22. The MBH–Mhost ratio as a function of z
G ≡ MBH/Mhost increases of a factor ~7 from z=0 to z=3
log G = (0.28 ± 0.06) z (2.91 ± 0.08)
Peng et al. (2006)
McLure et al. (2006)
Merloni et al. (2010)
Decarli et al. (2010)
Decarli et al (2010 a,b)

23. Conclusions
We probed the MBH-Mhost relation up to z=3, both for RLQs and RQQs
The MBH-Lhost is practically constant
Once we correct for the evolution of the M/L ratio, G increases of a factor ~7 from z=0 to z=3, similarly for RLQs and RQQs

25. What does it mean?
The MBH-Mhost ratio at z=3 is 7 times larger than at z=0
They move onto the local MBH-Mhost
Mhost increases with Cosmic Time through merger events
What is the fate of z=3 galaxies with MBH/Mhost~0.01?
Mhost increases by gas consumption
Evolution of the host galaxy fundamental plane
They do not move onto the local MBH-Mhost
Why don’t we see such high G in the local galaxies?

26. What does it mean?
They move onto the local MBH-Mhost
Mhost increases with Cosmic Time through merger events
Only 1-2 major mergers are expected (e.g., Volonteri et al., 2003)
Mhost increases by gas consumption
Stellar populations are old. If strong SF occurs, the G evolution is even stronger
Evolution of the host galaxy fundamental plane
MBH-s* studies also find a similar trend in G
They do not move onto the local MBH-Mhost
Why don’t we see such high G in the local galaxies?
The high-mass end of the MBH-host relations is poorly constrained, but…

28. Luminosity Function bias
The scatter in the MBH-Mhost (Lhost, s*, etc) relation introduces a bias (Lauer et al., 2007).
The steeper is the luminosity function, the larger is the bias.
 log MBH =  ((M2)-(M1)) / ∫M1M2 (M)dM

29. Radiation pressure?

30. N/H ratio