cracking the mystery of galaxy and black hole formation: rachel somerville mpia/stsci a theorists’...

Cracking the mystery of galaxy and black hole formation:

rachel somervilleMPIA/STScI

a Theorists’ Wish List for the next generation of Space Telescopes

Progress in the last 10-15 years

CDM paradigm shown to be consistent with broad range of observations (CMB, Ly- forest, weak lensing, galaxy clustering, galaxy clusters)galaxy surveys:

large homogeneous samples at low z huge progress in discovering & cataloging high-z

galaxies build-up of panchromatic view of the Universe

development of detailed simulations of dark matter and (to some extent) gas processes developments of (not totally im-)plausible picture for galaxy formation within this framework -- but...

Moster, rss et al. in prep; Benson et al. 2003; Somerville & Primack 1999

‘special’ scale Mh~1012 Msun

we still have to invoke several “tooth fairies” in order to reconcileCDM with fundamental observations:

stellar mass function andDM halo mass function

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ion o

f b

ary

on

s in

sta

rs

Moster, rss et al. in prep; Benson et al. 2003; Somerville & Primack 1999

we still have to invoke several “tooth fairies” in order to reconcileCDM with fundamental observations:

“Supernova feedback”

“AGN feedback”

The Biggest Outstanding Problems in Galaxy Formation

physics of star formation & stellar feedback from Giant Molecular Cloud (core) to galactic scalesinterconnection of galaxies and their (growing) black holes

The mysteries of cooling flows, overcooling, and quenched galaxies

z=1

Bell et al. 2005

Peterson & Fabian 2006

• why isn’t gas cooling (below 1/3 Tvir) in the centers of clusters?• what sets the maximum mass scale for galaxies (M* ~ 1012 Msun)?

• why is star formation“quenched” in massive, spheroidal galaxies?• why are galaxy propertiesstrongly bimodal?

gastrophysics or particle physics?

many dwarf & LSB galaxies have lower central densities and less “cuspy” density profiles than predicted by standard LCDM:

nature of dark matter or primordial power spectrum (e.g. Zentner & Bullock 2002; Strigari et al. 2007)

or stellar feedback (e.g. Mashchenko et al. 2007)?

rota

tion

velo

city

Simon et al. 2005(see also de Blok 2005)

Star formation and stellar/supernova feedback

what determines the efficiency of star formation on galactic scales? what drives the dependence on galaxy mass, redshift, or other properties?how effective are supernova-driven winds at heating and expelling gas from galaxies?

Kennicutt et al. 2007

Kennicutt et al. 1989

starbursts

galacticnuclei

normalgalaxies

requirements for sub-galactic resolution studies at high redshift

SDSS

HST z~1.2

the co-evolution of galaxies, AGN and SMBH

how did the first (seed) BH form and what were their masses?how was their growth triggered and regulated (mergers/bars, ADAFs, super-Eddington accretion)?How did BH spins evolve over time (related to efficiency of converting matter into energy)How does the energy from growing BH impact the host galaxy and its surroundings (winds, heating)?

understanding galaxy & BH formation: challenges

dynamic range: Gpc (luminous QSO) few 100 Mpc (LSS) 10’s of kpc - Mpc (ICM, jets) sub-kpc to kpc (star formation,

stellar FB) few 100 pc (nuclear gas inflows,

starbursts, AGN feeding, winds) pc & sub-pc (accretion disk, BH

mergers, etc)poorly understood physics (B-fields, conduction, cosmic ray pressure, turbulence, feeding problem, BH mergers...)

AGN feedback 1: bright mode

optical/X-ray luminous AGN/QSO, produced during periods of efficient feeding (mergers?)high accretion rates (0.1-1 LEdd), fueled by cold gas via thin accretion disk --> BH grows rapidlyrare-->duty cycle short radiation pressure can drive winds and perhaps galactic-scale outflows

Di Matteo, Springel & Hernquist 2005

lots of circumstantial evidence that (optical/X-ray bright) AGN are associated with quenching of SF...

weak AGN at z=0 live in massive, spheroids with young stellar pops; many are post-starburst (Kauffmann et al. 2003)strong correlation of with color; almost all ‘green valley’ galaxies host weak AGN (Kaviraj et al. 2006; Kauffmann et al. 2006; Salim et al. 2007)similar results seen for AGN to z~1 (GEMS: Sanchez et al. 2004; AEGIS: Pierce et al. 2006; Nandra et al. 2007)

Kauffmann et al. 2006

AGN

AGN-driven Winds

even more suspiciously, (a few of) these same post-starburst (green valley) galaxies show signatures of high velocity windssuch winds known to be fairly common in Seyferts and QSOs (e.g. Kriss 2002; Ganguly et al. 2001, 2007)but, typically covering fraction, column density & ionization state unknown -- hence mass outflow rates uncertain Tremonti, Moustakas, &

Diamond-Stanic 2007

AGN feedback 2: Radio ModeAGN feedback 2: Radio Mode

RadioRadio X-rayX-ray

3C843C84

many massive galaxies are ‘radio loud’radio activity believed to be associated with BH’s in ‘low accretion state’ (low Eddington ratio, <10-3) --(spherical, Bondi accretion or ADAF?)radio jets often associated with cavities visible in X-ray images; apparently they can very efficiently heat the surrounding hot gas and perhaps balance cooling...

FR IFR II

X-ray bubbles as ‘calorimeters’

Allen et al. 2006

the jet power (determined from energetics of X-ray bubbles) is proportional to the Bondi accretion rate.

Obtain X-ray maps &ancillary multi- datafor large sample of groups & clusters (tohigh redshift)

The BH Fundamental Planeblack hole masses in nearby galaxies are strongly correlated with many galaxy properties: L, Msph, , ns, re recently suggested that MBH possesses a “fundamental plane”, similar to that for galaxies (Hopkins et al. 2007)

Ferrarese & Merritt 2000Gebhardt et al. 2000

a similar “fundamental plane” is seen in the remnants of hydrodynamic simulations of galaxy mergers including BH growth and feedbackgas-rich mergers suffer dissipation and form a deeper potential well than gas-poor mergersrequires more energy, hence a larger BH to halt accretion in remnants of gas-rich mergers

Hopkins et al. 2007, astro-ph/0701351

gas fraction

BH/bulge mass

Physical origin of the BH FP?

strong prediction: evolution of mBH/msph with z; relationship with fgas and galaxy structural properties

Hopkins et al. 2007, astro-ph/0701351

measure BH masses and galaxy spheroid masses, sizes, and velocity dispersions over the broadest possible redshift range

Mission baseline: • 1.2m telescope• Visible: 0.5 deg2, pixels 0.10’’, broad R+I+Z, e2v CCDs• NIR: 0.5 deg2, pixels 0.15’’, Y,J,H, Teledyne HgCdTe• Dichroic Mirror• PSF FWHM 0.23’’, 2.2 pix/FWHM (vis)• GEO (or HEO) orbit with Soyuz Launch• 4-year mission

“All-sky” (20,000 sq.deg.)optical & NIR surveys

Imaging Survey Discovery Space:

Niche for wide field NIR imaging surveys -- HUGE advantages to going to space

High redshift (proto-) clusters from wide-field NIR imaging

use J-H to identify “red sequence” clusters to z=2-3 expect several 100 Virgo-mass

clusters & several 1000 M>1013 Msun “proto-clusters” at z>2

targets for study with ground-based radio facilities &next generation X-ray telescopes -- these should be theenvironments & redshifts of maximal AGN feedback!

Extreme Black Holesthe existence of luminous QSO’s at z>6 are already on the edge for the most “vanilla” picture of BH formation

super-Eddington accretion?

seed BH masses? spin up of BH? BH loss mechanisms

(recoil, rocket, slingshot)?

Jiang et al. 2007

Li et al. 2007; Volonteri & Rees 2006; Yoo & Miralda-Escude 2004; Haiman 2004; Bromley, rss & Fabian 2004

Searching for z>6.5 QSO’s“cloned” 215-some QSO spectra from SDSS (2.2<z<2.25) at higher redshift (including IGM absorption) to compute observed-frame colors in DUNE-like photometric system (ZYJH)

Fontanot, rss, Jester (astro-ph/0711.1440)

Color Selection of high-z QSO’s

can disentangleQSO’s from brown dwarfs

FSJ08

Luminosity Function Evolution

use observed QSO luminosity function at z=3.5-5.2, (SDSS+GOODS) plus simple model(s) for its evolution

Predicted high-z QSO counts

blue hatched: non-evolving F07 LF

yellow shaded: evolving F07 LF

red lines: steepestallowed LF at z~6,from Shankar &Mathur (2007) (evolving/non-evolving)

Fontanot, rss & Jester (2008)

DUNE

JWST

VISTA

Expected “backwards” evolution of most luminous z~6 QSO’s

r = 0.1

DUNE

JWST

Lyman break galaxies at z>7

Courtesy of C. Lacey

a DUNE Medium-deeplike survey would becomplementary to JWST for identifyinghigh redshift galaxies

JWST

DUNE

Wish List:

constrain relationship between DM and galaxies: mass maps from weak lensing, galaxy properties such as stellar mass, SFR, morphology, AGN activityconstrain mass outflow rates of stellar & AGN-driven winds (and dependence on luminosity, redshift, environment, etc) measure efficiency of “radio mode” heating via high spatial resolution X-ray imaging & radio observations of groups and clusters to z=2-3measure BH masses and galaxy masses, sizes, and kinematics to highest possible redshiftsfind the most luminous z>6 galaxies and QSOs

how wide do we need to go to overcome cosmic variance?

assuming redshiftshells z=0.1

how wide do we need to go to overcome cosmic variance?

‘typical’(b=1) galaxies

strongly clustered galaxies(EROs, proto-ellipticals, SCUBA galaxies)

constant minimum mass

constant number density

cosmic variance cheat sheet: rss et al. 2004

HOD model details in Moustakas & rss 2002

fract

ional ro

ot

vari

an

ce

how wide do we need to go to overcome cosmic variance?

‘typical’

(b=1) galaxies

strongly clustered galaxies

how wide do we need to go to overcome cosmic variance?

strongly clustered galaxies

‘typical’

(b=1) galaxies

how wide do we need to go to overcome cosmic variance?

‘typical’

(b=1) galaxies

strongly clustered galaxies

• DUNE Extragalactic All-Sky Survey: 20,000 deg2, |b|>30o, R+I+Z=24.5 (10s ext.), Y,J,H=24 (5s, PS), 40 WL galaxies/arcmin2, zm~1, photo-z with ground-based complement, 3 years• Medium Deep Survey: 2x50 deg2, R+I+Z=26.5 (10s extended), Y,J,H=26 (5s, PS), 6 months• DUNE Galactic Plane Survey: 21,000 deg2, |b|>30o R+I+Z=23.8, Y,J,H=22 (5s, PS), complete 4 coverage, 3 months• Microlensing Survey (DUNE-ML): 4 deg2 in the bulge, visited every 20 minutes over 3 months (Y,J,H~22 per visit), 3 months

Proposed DUNE Surveys

Galactic Plane21,000 deg2

Medium-Deep2x50 deg2

Microlensing4 deg2

Wide Extragalactic20,000 deg2

Weak Gravitational Lensing

z>1

z<1

• central goal of DUNE• constrain dark energy• map dark matter

Weak Lensing tomography:

Jain et al. 1997

130kpc resolution at supercluster redshift z=0.16

STAGES survey Heymans et al. submitted

Total Mass to stellar

mass ratio

Log

(M/M

*)

Old Red

Galaxies

Dusty Red Galaxies

Blue Galaxies

Courtesy of C. Heymans