Spheroid and Black Hole formation at high z James Dunlop Overview pulling together many different areas of work Major and minor contributions from: PhD students PDRAs/Afs Institute Staff Geoff Taylor Marek Kukula John Peacock Ian Waddington Dave Hughes Andy Lawrence Elese Archibald Raul Jimenez Alan Heavens Ross McLure Rob Ivison Louisa Nolan Omar Almaini Suzie Scott Bob Mann

Outline 1. Black-hole - Host-spheroid connection at low z 2. Out to high z with active black holes 3. Out to high z with quiescent black holes 4. Coupled black hole and spheroid formation at high z

HST studies of low-z quasar hosts RLQ 1217+023 RQQ 0923+201 RG 1215-033

Results - host morphologies Spheroid | Disc | All are ellipticals except 2 low-luminosity RQQs and 0052+251

Host morphology as function of nuclear power Schade et al. (2000) + McLure et al. (1999) & Dunlop et al. (2001)

Results - Kormendy relation Slope = 2.9 cf `normal ellipticals’ Slope = 2.95 (Kormendy 1985)

A detailed look at the Kormendy relation Discy ellipticals Faber et al. 1997 Boxy ellipticals Faber et al. 1997 ULIRGS Genzel et al. 2001

Cluster Environments - up to Abell Class 1/2 And biggest hosts are consistent with this, with scalelengths ~ 25 kpc We know of no low-z quasar hosts as big as first ranked galaxies in Abell Class 3 or 4 clusters e.g. Abell 2218 re = 100 kpc Abell 1689 re = 75 kpc but such clusters are so rare that even an all-sky survey in redshift band 0.1 < z < 0.25 would contain < 1500 Abell Class 3 or 4 clusters Therefore no quasars expected in these rare environments at low z because only 1 in 10000 black holes are active

Ages of quasar hosts Nolan et al. 2000

Ages of quiescent ellipticals

Black hole masses of quasars - now believable McLure & Dunlop 2001 Dunlop et al. 2001

Summary of Part 1 Low-z quasars are powered by black holes with M > 5 x 108 solar masses These black holes live in spheroids of expected mass Mbh = 0.002 Msph Spheroids have structural parameters and environments like boxy ellipticals Boxy ellipticals and quasar hosts appear old/evolved (12-13 Gyr) Quasar hosts in general not the result of recent ULIRG mergers But more moderate mass spheroids/AGN may be (e.g. seyferts) Low-z AGN = random activation of 1 in 10000 present-day black holes

Want to trace black-hole spheroid link out to high z - confine attention to high-mass end Look at hosts of known active black holes or Trace evolution of massive spheroids, and look for AGN activity in them

2. Hosts of active black holes out to high z Kormendy relations of 3CR radio galaxies at z = 0.2 and z = 1 - consistent with passive evolution (McLure & Dunlop 2000)

Age of oldest hosts at z = 1.5 Keck spectroscopy of red radio galaxies at z = 1.5 > 3 Gyr at z = 1.5 means formation z = 5 Dunlop et al. (1996) Peacock et al. (1999) Nolan et al. (2001)

Change in K-band morphology at z > 3 Van Breugel et al. (2001)

Radio galaxies are dusty at z > 3 L850 grows approximately as (1+z)3 (Archibald et al. 2001)

SCUBA imaging of radio galaxies Star-formation around z = 4 radio galaxies also prolific? SCUBA image of 4C41.17, z = 3.8 (Ivison, Dunlop, et al. 2000)

Summary of Part 2 z = 0 z = 1 z = 1.5 z = 2 z = 3 Host Size 10 kpc 10 kpc ? ? Messy Host Age 13 Gyr 5 Gyr 3 Gyr ? Star-forming % BH active 0.01 1 10-100 10-100

3. Hosts of passive black holes out to high z There have been claims that massive ellipticals don’t exist at z > 1 (e.g. Kauffman & Charlot 1998) But they could be hiding due to 1. Surface brightness bias - hard to recognize big extended ellipticals 2. Being very passive at intermediate z 3. Being dust-enshrouded during peak of SF activity at high z

Passively evolving ellipticals at 1 < z < 2 How many quiescent massive ellipticals are there today with masses comparable to radio galaxies? Integrate K-band luminosity function for L > 2 - 3 L* gives 1 - 5 x 10-5 Mpc-3 Substantial numbers of 53W091/53W069 analogues have now been found specifically surface density of objects with K < 18.5 and R-K > 5.3 is 350 per sq. degree (Daddi et al. 2000, 2001) Assuming 1 < z < 2, this gives a comoving number density = 3 x 10-5 Mpc-3

Higher z - SCUBA surveys? New results on surface density of bright SCUBA sources from 8mJy survey (Scott et al. 2001) Assuming most of these lie at z > 2 comoving number density of things forming > 1000 solar masses of stars per year = 1 - 3 x 10-5 Mpc-3

Are bright SCUBA sources high-z proto-ellipticals? SED constraints say z > 2 Identifications look like high-z radio galaxies Lutz et al. (2001)

Summary of Part 3 Question - Why are SCUBA sources not all bright AGN? Number density of massive ellipticals at z = 0 = 1 - 5 x 10-5 Mpc-3 Number density of comparably massive EROs at z ~ 1.5 = 3 x 10-5 Mpc-3 Number density of bright SCUBA sources at z > 2 = 1 - 3 x 10-5 Mpc-3 Question - Why are SCUBA sources not all bright AGN? And why are only high-z AGN SCUBA sources?

4. Spheroid and black hole formation Simple model of collapsing gas sphere of baryonic mass 1012 solar masses within dark matter halo 1-D chemical-evolution/hydro code with 100 zones Friaca et al. 1999, Star-formation, SN rate, metal production, cooling etc Jimenez et al. 1999 Models predict decline of gas growth of stars and rise and fall of dust in starburst commencing at z = 5

Rate of mass consumption by black hole Assume all mass dumped into central 100pc available to black hole Assuming initial black-hole mass =10 solar masses - get Eddington limited growth for most of first Gyr

Growth of black hole

AGN output compared with dust mass