black hole growth in the local universe
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Black Hole Growth in the Local
Universe
Jenny E. Greene (Hubble/Princeton-Carnegie Fellow)Luis C. Ho (Carnegie), Aaron J. Barth (UC Irvine)
Marconi et al. 2004
Galaxy luminosity function→BH mass function Primary mode of BH growth AGN lifetimes, radiative efficiency
Local BH Mass Functions
BHs Growing TodayHeckman et al. 2004
All BHs (active+inactive)
Narrow-line AGNsDistribution of L[OIII]
Broad-line AGNs- masses from AGN physics- compare broad and narrow line AGNs- sensitive to low-mass (<106 M⦿) BHs
Only means to probe this regime is using AGNs, since current resolution inadequate
for dynamical detection
Haehnelt 2004
But isn’t this a neglible fraction of total BH mass and radiated lumiminosity?
Disproportionate Import
LISA
Primordial Seeds
Bromm & Loeb
GC
dSph
dE
E
Merritt et al. 2004
Gravitational Recoil
Gravitational radiation
Stellar Mass
Low-mass BHs are rare?
Groves et al. astroph/0607311
All galaxies
Active galaxies (narrow-line)
Greene & Ho 2004 found only 19 broad-lineAGNs in DR1 (<106 M⦿)
The Search• z<0.35 broad-line AGNs from SDSS
•Galaxy Survey: r < 17.77; extended (e.g. Hao et al. 2005, Heckman et al. 2004)
•AGN Survey: 15 < i < 19.1; color-selected
PCA (Hao et al. 2005)
[S II] λλ6716, 6731
Hα + [N II] λλ6548, 6583
Modeling (Greene & Ho 2004)
~8000 AGNs, 2000 from main galaxy sample
LHα FWHMHα
Standard scaling relations (BLR radius and AGN
luminosity)
Greene & Ho 2005
MBH Lbol/LEdd
Greene & Ho in prep
Lbol/LEdd
0.01
0.030.10.3
1
Greene & Ho in prep
SDSS bright limit
Hα Luminosity Function
broad Hα luminosity function 8300 broad-line AGNs
Vmax method
Contaminants
Ho 2004
Greene & Ho in prep
BH Mass FunctionsGreene & Ho in prep
Text
?
“ Cosmic Downsizing”
MBH*
All T2s from SDSS
Greene & Ho in prep
Seyfert T2s
Broad-line AGNs
CF with Heckman et al. 2004
CF with Hasinger et al 2005
Soft X-ray LFInferred from optical
using αox
Monte CarloReal turnover at the low-mass end
ORlow-mass BHs are quiescent ORincorrect galaxy luminosities
z=0.05 z < 0.02 z =0.1
0.0
1 <
L/
L Edd<
0.1
0.1
<
L/L E
dd<
0.3
0.3
<
L/L E
dd<
3
log (MBH/M⦿)5 6 7 8 9 5 6 7 8 95 6 7 8 9
GH02 GH08 GH05
GH17 GH04 GH09
19 AGNs (<106 M⦿) Greene & Ho 2004HST/ACS: F435W (B), F814W (I), 1 orbit/source
Greene, Barth, & Ho in prep7 kpc
3 kpc
8 kpc
7 kpc
10 kpc
4 kpc
20 kpc
MBH-L
Bul
ge
Mar
coni
& H
unt
(200
3)
Greene & Ho 2004
NGC 4395
Pox 52
5 mag
GALFITPeng et al. 2002
Greene, Barth, & Ho in prep
PSF + 1 Sersic fit
Barth et al. 2004
Filippenko & Ho 2003
Barth, Greene, & Ho 2005
Lauer et al. 2006/astroph0606739Ferrarese et al. 2006
Star-cluster mass correlated with galaxy mass (see also Wehner & Harris 2006, Rossa et al. 2006)
Conclusions(preliminary)
• We construct BH mass functions using 9000 local broad-line AGNs from SDSS
• We investigate, for the first time, the space density of the lowest-mass AGNs known (<106 M⦿)
• Preliminary evidence that low-mass BHs are truly rare (or inactive)
• Alternate search techniques are desirable: deeper nuclear optical spectroscopic surveys, X-ray stacking, deep radio searches, tidal disruptions (LSST)
MBH-L
Bul
ge
Mar
coni
& H
unt
(200
3)
Greene & Ho 2004
NGC 4395
Pox 52
5 mag
GALFITPeng et al. 2002
Greene, Barth, & Ho in prep
PSF + 1 Sersic fit
Barth et al. 2004
Filippenko & Ho 2003
N 1068m
N 4261
N 821
N 1023
N 2778
N 3115
N 3377N 3379
N 3384
N 3608
N 4291
N 4473
N 4649
N 7457
N 7052g
N 6251g
N 2787G
M87G
IC 1459
N 3245
N 4697N 4596g
N 4564
N 4459g
N 4258m
M 32 M31
MW
MBH
MGal
Monte Carlo
•Distribution of MBH, L, z
‣Corresponding galaxy luminosities using MBH-Lbulge relations
‣Realistic S/N using SDSS
‣Spectroscopic completeness using simulations
Unreliable BH Masses
Bulge/Total ratio poorly constrained
for low-mass BHs
z=0.02 z=0.05 z=0.1
L bol/L
Ed
d =
0.0
1L b
ol/L
Ed
d =
0.1
L bol/L
Ed
d =
1
z=0.05 z=0.02 z=0.1 L
/LEdd=
0.0
1L/
L Edd=
0.1
L/L E
dd=
1
log (MBH/M⦿)4 6 8 4 6 8 4 6 8
Real incompletenessat the low-mass end
ORbiased galaxy sample
ORlow-mass BHs are quiescent
Maximum-Likelihood
Contaminants
Contaminants
Contaminants
Marconi et al. 2004
Which BHs are growingToday?
Heckman et al. 2004
Narrow-line AGNs
SDSS Galaxies
Fundamental Plane?
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