Download presentation
Presentation is loading. Please wait.
1
ACCRETION MODELS FOR BLACK HOLE EVOLUTION Francesco Shankar In collaboration with: D. Weinberg J. Miralda-Escude’ L. Ferrarese A. Cavaliere S. Mathur CCAPP/OSU BH WORKSHOP 10/2/07
2
EMPIRICALLY CONSTRAIN BLACK HOLE EVOLUTION IN A STATISTICAL SENSE WE USE: -LOCAL BH MASS FUNCTION -AGN BOL. LUMINOSITY FUNCTION - AGN CLUSTERING GOAL: TOOLS:
3
For All relations convolve with an “intrinsic” scatter! How many? How Much? Φ(L) → Φ(L bulge ) M BH - L bulge Ф(M BH ) M BH - ( )= (L) +L-
4
The Local Black Hole Mass Function Systematic and shape uncertainties…. Log M PEAK ~8.5
5
The Bolometric AGN Luminosity Function
6
Soltan argument Single object independent of cosm. par. but very dependent on the ratio K bol /ε ! SMBH from Merging/Dark Accretion or through Visible Accretion detected in the AGN luminosity Functions?
7
Parallel growth of Stars and Black Holes The ratio probably was nearly constant at all times…. Soltan’s constraint: 0.055 < < 0.11 Shankar et al. 2007 Shankar & Mathur 2007 Shankar, Cavaliere et al. 2007
8
Varying the Reference Model…
9
Consequences on BH accretion… dm/dt(z) dm/dt(M BH ) Only works with P(z=6)~0.02 and Super-Edd accretion
10
Shankar & Ferrarese 2007 Bias in the M BH -n relation??
11
The Reference Model matches the Clustering of luminous AGNs
12
CONCLUSIONS 0.06< <0.11 dm/dt~0.5 More Massive+Sub-Edd Less Massive+Edd Merging +AGN LF
13
A Reference Model
15
CONCLUSIONS Normalization --> Radiative Efficiency 0.06< <0.11 Peak+Clustering --> Edd. ratio of massive BHs dm/dt~0.5 probably significantly decreasing at z<1 High End --> Merging events NOT much
16
The Effect of Merging… Negligible effect on accretion histories and duty cycles:
17
Further constraints from AGN BIAS IDEA: Use the duty-cycles as produced from accretion -Need to relate BHs to Dark Matter -Further independent test for accretion parameters Shankar & Weinberg 2007
18
Varying the accretion rate: L~dm/dtM BH ~M H
19
Remember: L~(dm/dt)M BH ~M H
20
Shankar, Miralda-Escude’ et al. 2007 High Duty cycle at z~6 excluded by the bias… Successful model: P(z=6)~0.5-1 dm/dt~1 STAR /V vir ~0.55-0.6 Data from Shen et al.
21
CONCLUSIONS Use of the Local Mass Function and AGN Luminosity Functions to constrain dm/dt and Use AGN clustering to constrain further duty-cycles and where Soltan is not sensitive and also probe dependencies on mass/luminosity of dm/dt FOR THE FUTURE….even worse… Towards a multiple dm/dt…build a general P(dm/dt,z,M BH ) to compare to the data Insert HOD models for AGNs, which could be derived from those of galaxies and apply our average P(M,t)…
22
Again Radio AGNs..Clustering useful here as well… Shankar 2007 A sequence of very strong decreasing dm/dt can explain both Clustering and SED…
23
Changing the Luminosity Function of AGNs…
24
The Bolometric AGN Luminosity Function
25
BH
26
A First Estimate of Clustering: The Space Density of AGNs Hosts!
27
Here I am using an empirical relation calibrated with a one-to-one approximation…
28
The Soltan argument can also be applied to Radio AGNs only… Shankar, Cavaliere et al. 2007 L radio ~f radio L kin L kin ~f kin L L~ dm/dt c 2
29
Constrain the relation between Luminosity and halo mass… Independent of duty-cycle It can give “hints” on the best relation between M BH and M H Which fits the bias… But then take care to fit the LF!! Shankar & Weinberg 2007
30
Further constraints from AGN BIAS IDEA: Use the duty-cycles as produced from accretion -Need to relate BHs to Dark Matter -Further independent test for accretion parameters Shankar & Weinberg 2007
31
Massive Dark Objects observed in all bulged-galaxies strong link with the host spheroid M/n/ What are MDOs? How and why are they connected with spheroids and DM? What is their role in shaping galaxies? Marconi & Hunt M BH R e 2 Log M BH ~0.25 dex V C +DM profile V VIR (z vir =0) (M vir ) 1/3 =k V c +
32
The XRBG is mostly made of..AGNs!!!
33
Evolving the black hole Accreted Mass Function…. insert and dm/dt evolve masses at each timestep average rate proportional to “probability” “probability” given by the fraction of active BHs Require initial duty-cycle but at z<3.5 mass function evolves INDEPENDENT of the ansatz…
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.