Coeval Evolution of Galaxies and Supermassive Black Holes : Cosmological Simulations
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Transcript of Coeval Evolution of Galaxies and Supermassive Black Holes : Cosmological Simulations
Coeval Evolution of Galaxies and Supermassive Black Holes : Cosmological Simulations
J. A. de Freitas Pacheco Charline Filloux
Fabrice Durier Matias Montesino
Collaborators J. Silk – Oxford
T.P. Idiart – USP Miguel Preto - Heidelberg
The Facts
Observational evidences for the existence of massive BH in the core of galaxies
Sagittarius A* - galactic centre
Ghez et al. 1998
DMO in M87, M84 and NGC4261
Black holes and galaxies
Strong correlations are observed between the black hole mass and :
Stellar velocity dispersion :
Stellar bulge mass :
Stellar bulge luminosity :
Co-evolution of SMBH and galaxies
Dark halo mass :
3.5 4.5M ˜
1.12lgbu eM M˜
1.26BM L˜
Tremaine et al. 2002 ; Gebhardt et al.2000
Haring and Rix, 2004
Marconi and Hunt, 2003
1.27haloM M˜Baes et al. 2003
Lower Mass Limits
* Lower limits
- negative searches for intermediate
mass black holes
- upper limits for M33 (3103 M ) and
NGC 205 (3.8104 M )
-indirect evidence for IMBH in NLSeyf1
(8104 - 8106 M )
Origin & Evolution of SMBH
Origin of Seeds
(*) Intermediate mass black holes (103-104 M) formed in : a) the collapse of primordial gas clouds (Haehnelt & Rees 1993)b) the core collapse of star clusters formed in starburts (Shapiro 2004)
(*) Collapse of primordial massive stars (100-300 M) formed in highdensity peaks of the primordial fluctuation spectrum
Cosmological simulations
Advantages
• follow up of seeds• gas dynamics & merger tree• follow up of the star formation history
Difficulties
Two extreme scales :Galaxies interactions : several kpcBlack hole physics : sub-pc scales
Number of Particles Mass resolution (gas)
V=(50 Mpc)3
CPU/hours/run
(128 processors)
21603 5.35108 M 4 000
21923 3.09108 M 12 000
22563 1.30108 M 60 000
v=0.7 m=0.3 bh2= 0.0224 h=0.70 8=0.9
The Code
GADGET-IISpringel 2005
Gravitation(tree code)
Hydrodynamics(SPH)
DARK MATTER GASSMBH
Introduction of BH seeds at potential
minima (z=15)
BH Growth(« disk » and HLB mode)
AGN activity (feedback)
STARS
Star formation (conversion of gas
into tars)
Ionisation, heating and
radiative cooling
Supernovae (type Ia and II)
Galactic winds
Metal enrichment
SMBH coalescences during galaxy
mergers
Code Parameters
,
510.03 0.2
10Ia II
SNE erg
Energy injected by supernovae
1n
wr
Weight for the blast energy per particle i SNi N
ii
w E
Nw
’’turbulent’’ diffusion efficiency 20.1 0.2tD t
L
Accretion mode spherical (Bondi – Hoyle) ’’disk’’ 2
6 sc VdM
dt QG
AGN feedback
gravitational energy
rotational energy
0.1J AGN bol AGNL L 2
2 2
max2J horA
c SL H cr
V S
Jet angle 20 ,45 ,180o o o Jet length 100 - 400 kpc
Detection of Structures
FoF SubFind
Davis et al, 1985 ; Huchra and Geller, 1982 Springel et al, 2001
Structure determination
Properties of Galaxies
Dynamical Properties of Simulated Galaxies
Faber-Jackson & Tully-Fisher relations Angular momenta of blue & red galaxies
’’Red’’ galaxies (U-V)>1.1 and (B-V)>0.8’’Blue’’ galaxies otherwise
Properties of Simulated Galaxies
Grey zone – SDSS data from Gallazzi et al. 2005
Properties of Simulated Black Holes
The mass function at z=0
All simulations give similar results, with BHMF slightly overestimated for M● >107M
BH seeds of 100 M: evolution of massive pop III stars
192/160 : resolution disk/kerr : AGN feedback from accretion /rotation
S : with higher SNIa efficiency
Evolution of the Black hole mass density
Simulation ρ●(z=0) [M.Mpc-3]
MBH,min
[M]
160kerr 5.0 x 105 2.4 x 104
160disk 9.6 x 105 1.8 x 104
160diskS 7.4 x 105 3.7 x 103
192disk 8.2 x 105 1.2 x 103
Estimates : ρ●= 2 - 9 x 105 M.Mpc-3
Chokshi and Turner 1992 ; Salucci et al., 1999 ; Aller and Richstone, 2002 ; Marconi et al, 2004, …
192/160 : resolution disk/kerr : AGN feedback from accretion /rotation
S : with higher SNIa efficiency
Assuming bolometric luminosity proportional to the accretion rate
Black hole mass density at z=0
The M● - σ relation
Cygnus A, NGC 5252, NGC 3115 and NGC 4594
Good agreement, except for the four galaxies having black holes apparently too massive.
192disk simulation
The M● - Mhalo relation
Good agreement with Baes et al, 2003.
Mhalo is directly extracted from simulations.
192disk simulation
Some problems: no SMBH at z ~ 6!
No supermassive black holes at z=6 hierarchical growth
No super-Eddington accretion rates are observed (resolution effect?)
Gravitational Waves from Coalescences
Coalescence of two massive BHs
tThre
Four regimes can be recognized:i) adiabatic – sequence of quasi-circular geodesic orbitsii) transition – near the innermost stable orbitiii) plunge – merger of the two horizonsiv) ring-down – normal modes of the distorted black hole
Maximum mean frequencies – adiabatic regime
21 2
1 2
0.052( )gw
M ME c
M M
Total energy radiated under theform of GW in the adiabatic phase
5682( )gw lso Hz
M
Frequency near the ’’last stable orbit’’
Expected contribution to the background
max 2
min 1
1/3 7 /3 30
( ') '( ) ( , ')
(1 ') (1 ')o
z
o z v m
c z dzK P z d
H v z z
Expected flux at the observer’s frame
With 1 21/3
1 2( )
M M
M M
and ( )z total merger rate per
comoving volume
3
1( ) oo
gw gwc c
Equivalent density parameter
( , )P z Fraction of mergers with a parameter occurring at z
Ring-down contribution to the background
Expected flux
max
min
3 2
4 30
( ') '( ( ') /(1 ') )
(1 ') (1 ')o
z
oo z v m
c G z dzG z z
H z z
Equivalent density parameter 3
1( ) oo
gw oc c
0.3
2
100 63 ( )( ) 12 1 ( ) ( )
37 37
c J zG z a z kHz a z
GM
2
1
3 2
300 0
2 ( ') '( ) ( ') ( , ')
3000 (1 ')
Mz z
gw s
Mv m
c r z dzD z dR z M M z dM
H z
Duty cycle
Ring-down background(shot-noise – D <<1)
Spin data: Daly 2009 Shot-noise
I. Conclusions
• Cosmological simulations are the best tool to study the coeval evolution of galaxies and their central black holes
• Properties of gas, galaxies and the growth of supermassive black holes depend strongly on feedback mechanisms, in particular the downsizing effect
• Simulated galaxies have adequate mass profiles, satisfying the Faber-Jackson (red galaxies), the Tully-Fisher (blue galaxies) and the mass-metallicity relation
II. Conclusions• Seeds ( ~ 100 M) originated from the evolution of zero metallicity massive stars
are able to explain SMBH, by growing through accretion and coalescences
• Simulated SMBH satisfy the mass distribution observed in the local universe as well as the evolution of the BH mass density, the M● vs and the M● vs Mhalo relations
• Gravitational waves can put strong constraints on the coalescence history of seeds
• However, difficulties exist such:
a) no SMBH are seen at z ~ 6
b) density of massive galaxies are overestimated
c) simulated <Fe> and Mg2 indices still do not reproduce adequately the observations
d) blue galaxies do not have enough angular momentum