1. Quasars: old black holes with young stars (?)
Knud Jahnke
Max-Planck-Institut für Astronomie, Heidelberg
(?)
Sebastián F. Sánchez (CAHA)
Lutz Wisotzki (AIP)
Asmus Böhm (AIP)
Isabelle Gavignaud (AIP)
+the GEMS team
Eva Schinnerer (MPIA)
Vernesa Smolcic (MPIA)
+the COSMOS team(s)
Frederic Courbin (Lausanne)
Geraldine Letawe (Liege)
Lutz Wisotzki
et al.

2. State of the art:
luminous QSOs lie in massive bulges (not only E)
most BH mass accretion in high-L type 1 QSOs
accretion at 10%—100% Eddington
Goals:
state & evolution of QSO host galaxies
role of QSOs in general galaxy formation & evolution (and vice versa)
host diagnostics: luminosities, morphologies, stellar composition, gas state, interactions

3. Imaging and spectroscopy samples
GEMS/E-CDFS: 80 type 1 QSOs z<3)
optically selected and photo-z‘s (COMBO17)
V, z band optical ACS imaging
COSMOS: 120 type 1 QSOs, z<2.5 (future: ~500)
optically selected (SDSS & SDSS+MMT)
radio selected (VLA-COSMOS)
spectro-z‘s (IMACS, zCOSMOS, SDSS)
i band ACS imaging
VLT spectroscopy: 20 type 1 QSOs, 0.05<z<0.35
3 grisms optical, 3500—9000Å

4. Broad-line AGN sample: redshift distribution (z<3)
COSMOS
120 QSOs
55 QSOs
GEMS

5. 2“
F606W
(GEMS)
500 stars
4500 stars
F814W
(COSMOS)
F850LP
(GEMS)

6. 0.3–0.7
0.9–1.0
1.0–1.15
1.15–1.3
1.3–1.5
1.5–1.6
1.6–1.8
1.8–1.9
1.9–2.1
2.1–2.9
z =
COSMOS ACS F814W 4“

7. 0.3–0.7
0.9–1.0
1.0–1.15
1.15–1.3
1.3–1.5
1.5–1.6
1.6–1.8
1.8–1.9
1.9–2.1
2.1–2.9
z =
z=0.65
z=1.53
z=2.16
z=2.24

8. 0.3–0.7
0.9–1.0
1.0–1.15
1.15–1.3
1.3–1.5
1.5–1.6
1.6–1.8
1.8–1.9
1.9–2.1
2.1–2.9
z =

9. Current status & knowledge
COSMOS: ~50/120 resolved type 1 QSO hosts
Jahnke et al. (in prep)
GEMS: ~45 resolved (with optical colour)
Sanchez et al. 2004
Jahnke et al. 2004
Others: Kukula/Dunlop et al., Hutchings et al., Falomo et al., Peng et al., Kuhlbrodt et al. (at high z, 1–10 objects each)

10. GEMS & ground based colours
B&C03 (solar)
disk dominated
bulge dominated
undecided

11. GEMS z=0.7 mag-size relation
Inactive:
z=0.7
z=0

12. COSMOS: host galaxy luminosities

13. COSMOS+GEMS: homogeneous inactive comparison samples
z=0.6
z=1.0

14. COSMOS+GEMS combined
GOODS-MUSIC
(Grazian et al. 2006)
Radio detected

15. Diagnostic power
Differential host galaxy evolution compared to inactive galaxies
Influence of interaction on QSO activity (from merger fraction)
Test unified model for AGN from radio loud—quiet & type 1—type 2 comparison (luminosities, morphology)
QSO host galaxy parent population
With 2nd COSMOS (HST?-) band: spectrum of interaction strength triggering AGN activity (5% of QSOs with NICMOS data); trying Subaru 0.5“ seeing data

16. QSO host spectroscopy: on-nucleus
FORS slitlets
Centered on QSO
PSF star in the field

17. 2d host galaxy spectrum
total
host

18. QSO host spectroscopy
Jahnke et al., submitted to MNRAS

19. Sample 20 type 1 QSOs Hamburg/ESO survey 0.05 < z < 0.35
Imaging available

20. Property overview 20/20 successful host galaxy extraction
7 confirmed disk dominated, 2 bulge dominated
1 QSO with very faint host galaxy (upper limit)
Publication:
Courbin et al. 2002, A&A, 394, 863
Letawe et al. 2004, A&A, 424, 455
Magain et al. 2005, Nature, 437, 381
Letawe et al., submitted to MNRAS
Jahnke et al., submitted to MNRAS

21. QSO host spectroscopy Trager et al. 1998 early type galaxies
Kennicutt et al late type galaxies
Letawe et al., submitted to MNRAS

22. ISM state
Letawe et al., submitted to MNRAS

23. rotation
disturbed
Letawe et al., submitted to MNRAS

24. Results/conclusions/summary
BL QSO host galaxies are very luminous
Radio selected type 1 QSO are (on average) more luminous than optically selected
Host galaxies span colour range from reddish to blue  contribution of young stars
Early type hosts can be substantially bluer/have younger stellar populations than inactive counterparts (confirmed for z<1.1, SDSS+HES+GEMS)
No extreme starbursts!
Moderate to substantial UV flux at z~2, similar to LBGs
Merger/distortion fraction seems increased (to be quantified!)