1. Active intermediate-mass black holes (MBH<106 Msun)
Population census, a case study & how to find more
Mónica Valencia-S.
I. Physikalisches Institut. Universität zu Köln
In collaboration with: A. Eckart, J. Zuther, C. Iserlohe, M. Garcia-Marin, A. Zensus, S. Smajic, M. Vitale, G. Busch, S. Fisher, L. Moser, M. Bremer, C. Straubmeier

2. Over-classification vs. Unification
SDSS J z= (c) SDSS
Cen A .(c) NASA, CXC, CfA, R.Kraft+, MPIfR, ESO, WFI, APEX, A.Weis+
NGC (c) NASA, CXC, MIT, STSc I, C. Canizares, and M. Nowak
Galactic Center. (c) NASA,CXC,MIT, F.Baganoff+
HE HE (c) NASA,ESA, F. Courbin, and P. Magain

3. Geometrical Unification of Active Galactic Nuclei (AGN)
Low obscuration Broad Lines ( km/s) + Narrow Lines (100 km/s)
Type 1 BH
Accretion Disk
BLR
Torus
NLR
Type 2
Obscuration (NH >1022 cm-2) Narrow Lines (100 km/s)
Composed illustration. Originals (c) NASA/CXC/M.Weiss, K..Meisenheimer

4. Unification parameter 2?
UV signature of SS disk “Big Blue Bump”
Lbol/LEdd ~0.1 (BL AGN)
High Accretion rate
Thin disk
BBB
Broad lines
Radio quietness
QSOs
Seyferts
NLSy1s
Advection Dominated / Radiatively Inefficient Accretion Flow
Lbol/LEdd ~ (no BLR)
Low Accretion rate
Thick disk (ADAF/RIAF)
No BBB
No Broad lines
Radio loudness
FR I sources
LINERs
LLAGNs
Trump see also Nicastro 200, Elitzur &Ho 2009

5. IRAS 01072+4954 in brief IRAS 01072+4954 Low-luminosity AGN (LLAGN)
Starburst galaxy: ~5 Msun/yr
Pseudo-bulge <--Secular evolution
Unobscured Sy2:
LX(2-10keV)= erg/s
NH < 4.0 x 1020 cm-2
Low-mass black hole: MBH ~ 105Msun
High accretion rate:
Lbol~ erg/s, m~0.2
FWHMbroad lines~500 km/s
LBT/LUCI. Infrared: K-band. Courtesy: J. Zuther
No Broad lines in optical, no FeII
GEMINI/NIFS 3’’x3’’ Field-Of-View

6. Unification parameter 2?
Lbol/LEdd ~0.1 (BL AGN)
High Accretion rate
Thin disk
BBB
Broad lines
Radio quietness
QSOs
Seyferts
NLSy1s
Lbol/LEdd ~ (no BLR)
Low Accretion rate
Thick disk (ADAF/RIAF)
No BBB
No Broad lines
Radio loudness
FR I sources
LINERs
LLAGNs
Trump see also Nicastro 200, Elitzur &Ho 2009

7. Brγ λ μm
F(Brγ) = 1.0 x erg s-1 cm-2
FWHM(Brγ) = 420 km/s
S/N~2.8
IRAS
BH Accretion:
Lbol/LEdd~0.2
M ~ 4.4 x 10-4 Msun/yr
Broad Line Region:
rBLR ~ 1 light-day ≈ 105 RS
F(Hα) = ( ) x erg s-1 cm-2
FWHM(Hα) = 430 – 600 km/s
F(Brγ) ≈ F(Hα) / 100

8. Unification parameter 2?
Lbol/LEdd ~0.1 (BL AGN)
BL AGN
Stern & Laor 2012
Lbol/LEdd ~ (no BLR)
LINER 1s
Trump see also Nicastro 200, Elitzur &Ho 2009
Younes+ 2012

9. Unification parameter 3?
Sy Sy Singh+,2011
TrueSy2 candidates Laor,2003
IMBH & NLSy1 Dewegan+,2008
Low Mass Sy Carol+,2009
LEdd

10. Unification parameter 3?
Sy Sy Singh+,2011
TrueSy2 candidates Laor,2003
IMBH & NLSy1 Dewegan+,2008
Low Mass Sy Carol+,2009
IRAS01072

11. Unification parameter 3?
Radio Loud NLSy1
Foschini (2013)

12. Unification parameter 3?
Radio Loud NLSy1
Foschini (2013)
Jet (radio) vs. disk luminosity in BHs
Foschini (2012)
IRAS01072

13. Why are IMBHs important?

14. Why to study IMBHs?
IMBHs are the connection between SMBHs and stellar BHs

15. Why to study IMBHs?
IMBHs are the connection between SMBHs and stellar BHs
IMBHs are fundamental to probe models of SMBH seeds
Greene 2012

16. Why to study IMBHs?
IMBHs are the connection between SMBHs and stellar BHs
IMBHs are fundamental to probe models of SMBH seeds
IMBHs are the most active population of BHs in the local universe (dowinsizing)
IMBHs seem to be in an early stage of evolution, therefore they can help on understanding how BHs grow

17. Why to study IMBHs?
IMBHs are the connection between SMBHs and stellar BHs
IMBHs are fundamental to probe models of SMBH seeds
IMBHs are the most active population of BHs in the local universe (dowinsizing)
IMBHs seem to be in an early stage of evolution, therefore they can help on understanding how BHs grow
IMBHs seem to reside in young galaxies (starbursts), therefore they are important to recognize the nature of the star formation – AGN relation
IMBHs seem to prefer spiral galaxies with bars or pseudobulges, therefore they might probe a different type of BH fueling
IMBHs show signatures that might allow to probe the metal enrichment of the BLR in AGNs

18. How many IMBHs have been detected?
Extracted from: Hubble Ultra Deep Field. (c) NASA/ESA/S. Beckwith(STScI) and The HUDF Team.

19. From optical observations
Population census
From optical observations
SDSS DR7 Stern & Laor 2011:
106<MBH<109.5
10-3<Lbol/LEdd<1
SDSS DR4 Dong+2012:
8x104<MBH<2x106
 3% are LINER 1
3% host an AGN
3% host an AGN

20. From optical observations
Population census
From optical observations
SDSS DR7 Stern & Laor 2011:
106<MBH<109.5
10-3<Lbol/LEdd<1
SDSS DR4 Dong+2012:
8x104<MBH<2x106
 3% are LINER 1
3% host an AGN
3% host an AGN
From X-rays:
Desroches & Ho 2009, Ghosh+ 2008
M*,gal<1010Msun 20% - 25 % Lx >2.3x1038 erg/s

21. From optical observations From multiwavelength campaigns
Population census
From optical observations
From multiwavelength campaigns
SDSS DR7 Stern & Laor 2011:
106<MBH<109.5
10-3<Lbol/LEdd<1
SDSS DR4 Dong+2012:
8x104<MBH<2x106
 3% are LINER 1
Foschini 2011:
From 76 NLSy1  46 radio loud
 30 radio quiet
From 49 RLNLSy1  12 γ-emitters
3% host an AGN
3% host an AGN
From X-rays:
~ 310 low-mass BH
(z<0.35)
Desroches & Ho 2009, Ghosh+ 2008
M*,gal<1010Msun 20% - 25 % Lx >2.3x1038 erg/s

22. How to find more IMBHs?

23. From optical observations
How to find more?
From optical observations
Problems:
- Obscuration
- Dilution of the AGN by the stellar continuum
LAGN,B Lbol/LEdd (M*,gal / Lgal,B) B
Lhost,B (Msun/Lsun) T
B/T : ratio stellar mass of the bulge to total stellar mass =
NGC (c) Cord Scholz
For maximal accreting BHs:
LAGN/Lhost (Sa) ~ 45
LAGN/Lhost (Sc) ~ 7

24. From optical observations
How to find more?
From optical observations
Problems:
- Obscuration
- Dilution of the AGN by the stellar continuum
LAGN,B Lbol/LEdd (M*,gal / Lgal,B) B
Lhost,B (Msun/Lsun) T
B/T : ratio stellar mass of the bulge to total stellar mass =
LAGN
Lhost
α MBH
MBH
M*,bulge
~ 0.001

25. How to find more? MBH – M*,bulge relation
log (MBH) = -1.0 (MK )
Valencia-S
IRAS 01072
Graham+2012
IRAS 01072

26. How to find more? MBH – LK,bulge relation
log (MBH) = -1.0 (MK )
Valencia-S+ (Jun.) 2012
IRAS 01072
log (MBH) = (MK )
Graham & Scott (Dec.) 2012

27. From optical observations
How to find more?
From optical observations
Problems:
- Obscuration
- Dilution of the AGN by the stellar continuum
LAGN,B Lbol/LEdd (M*,gal / Lgal,B) B
Lhost,B (Msun/Lsun) T =
For MBH > 7x107 Msun:
For IMBHs with 105 Msun < MBH < 106 Msun:
MBH
M*,bulge
~ 0.001
MBH
M*,bulge
~ 10-5 – 10-4

28. From X-ray observations
How to find more?
From X-ray observations
A max. accreting BH with MBH=105 Msun:
LEdd = 1043 erg/s
 LX(2-10kev) ~ 1042 erg/s

29. From X-ray observations
How to find more?
From X-ray observations
A max. accreting BH with MBH=105 Msun:
Like IRAS (z=0.0236):
MBH~105 Msun
Lbol/LEdd ~ 0.2
FX(2-10keV)=3.1 x erg s-1 cm-2
Chandra (~ 25 ks)
LEdd = 1043 erg/s
 LX(2-10kev) ~ 1042 erg/s
Sensitivity limit Chandra (2-10keV):
FX~ erg s-1 cm-2 (~ 20ks)
 not detectable z > 0.2

30. From X-ray observations
How to find more?
From X-ray observations
A max. accreting BH with MBH=105 Msun:
Like IRAS (z=0.0236):
MBH~105 Msun
Lbol/LEdd ~ 0.2
FX(2-10keV)=3.1 x erg s-1 cm-2
Chandra (~ 25 ks)
LEdd = 1043 erg/s
 LX(2-10kev) ~ 1042 erg/s
Sensitivity limit Chandra (2-10keV):
FX~ erg s-1 cm-2 (~ 20ks)
 not detectable z > 0.2
IMBHs: 105 Msun < MBH < 106 Msun
Dong /49 detections (S/N>3)
z < (D < 350 Mpc)
FX(2-10keV) > erg s-1 cm-2

31. From X-ray observations
How to find more?
From X-ray observations
Stellar BH with MBH~ 10 Msun:
LEdd = 1039 erg/s
 LX(2-10kev) ~ 1038 erg/s
Threshold on the Eddington ratio of IMBHs:
Artist impression. (c)ESO/ L.Casada
LX(AGN)min ~ 1040 erg/s
For MBH = 105 Msun  Lbol/LEdd ~ 0.001

32. There is still some hope
From Infrared observations
Volume-weighted space density of active SMBH in the local Universe Goulding+ 2010

33. Thanks!