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Census of Active Super Massive Black Holes Active Super Massive Black Holes in the Era of Violent Growth

Masayuki Akiyama (Tohoku Univ ) Masayuki Akiyama (Tohoku Univ.) 秋山 正幸 (東北大学) 2013/01/27 Hokkaido University

Black hole mass function (BHMF) and Eddington radio distribution function (ERDF)

• f AGNs at z~1.4

Masayuki Akiyama, Kazuya Nobuta (Tohoku Univ.) f Yoshihiro Ueda (Kyoto Univ.), Mike Watson (Univ. of Leicester), John Silverman (IPMU), SXDS members FMOS GTO members SXDS members, FMOS GTO members Nobuta, MA, et al. ApJ, 761, 143 p

Relation between BH mass vs. bulge “mass”

Massi e gala ies ha e a s per massi e BH at their center and the mass of the Massive galaxies have a super massive BH at their center and the mass of the SMBH correlates with the mass of its host bulge. We want to understand the origin

• f the SMBH by qualitatively revealing

1) How the SMBHs have grown in the history of the universe ? ) g y 2) What links between the evolutions of SMBHs and galaxies ? McConnell et al. 2011 1) 2) 1)

Schematic View of Growth History of Super Massive BHs

Gas accretion from galaxy scale = “Feeding” Merging Merging Feeding Merging

SEED BHs

Outflow etc. affecting galaxy scale properties = “Feedback”

SEED BHs In young “spheroids” SMBHs sitting in “spheroids” consists with old stars

Accretion growth phase can be

• bserved as various types of AGNs

Growth history of Super Massive BHs

Gas accretion from galaxy scale = “Feeding” Outflow etc. affecting galaxy scale properties = “Feedback”

In order to qualitatively understand the growth history, for each SMBHs we want to know 1. Accretion rate ~ Bolometric luminosity / Radiation efficiency 2. Black hole mass 3 G th ti l A ti t / M Eddi t ti 3. Growth timescale ~ Accretion rate / Mass = Eddington ratio 4. Duty cycle ~ Fraction of galaxies with active black hole

Active BH Mass Function and Eddington Ratio Distribution Function of Broad-line AGNs in the Local Universe

Kelly et al. 2012 Schulze and Wisotzki 2010 Points: observed Lines: observational limit corrected by Maximum Likelihood

Rather steep active BH mass function and Eddington ratio distribution

Lines: observational limit corrected by Maximum Likelihood method assuming constant ERDF for the sample mass range

p g function mean no typical active black hole mass or no typical Eddington ratio in the local universe.

Cosmological Evolution of Number Density of AGNs

Low-luminosity AGN S f t Seyferts (< 1 Msolar/yr) Luminous QSOs (> 1 Msolar/yr) (> 1 Msolar/yr) Ueda, MA, et al. in prep. p p

Based on X-ray selected AGNs from Subaru-XMM Newton Deep Survey and other X-ray surveys.

Accretion rate distribution at z=1-2

~ 1 Msolar/yr ~ 1 Msolar/yr Ueda, MA, et al. in prep.

Luminosity function reflects the accretion rate distribution. L L 44 5 ( 1) d t 1 M l / ith di ti Log Lx=44.5 (erg s-1) corresponds to 1 Msolar/yr with radiation efficiency of 0.1.

Era of Violent Growth of SMBHs

Hard X-ray luminosity density reflects the total accretion rate density at each redshift, like UV or IR luminosity density reflects the star formation rate density at y each redshift. The peak of the hard X-ray luminosity density suggests rapid growth of SMBHs happened at z=1-2.

Aird et al. 2010

SXDS sample

30’ diameter

SXDS sample

866 and 645 X-ray sources are detected in XMM-Newton images in the 0.5-2.0 and 2.0-10.0 keV bands (Ueda et al. 2008). 945 sources are covered by the deep Subaru/Suprime-cam images (Furusawa et al. 2008). Removing candidates of clusters of galaxies and galactic stars, 896 sources remain as candidates of AGNs. Optical spectroscopic observations cover: 590 sources FMOS GTO NIR spectroscopic observations cover: 851 sources p p 586 sources have spectroscopic-redshifts 304 out of 310 remaining sources have secure photometric redshifts determined with photometry in the wavelength range between 1500A (GALEX) to 8um (Spitzer IRAC). (3.6 um IRAC data f f f are crucial for identification of the X-ray sources.)

SXDS AGNs at z=1-2

For black hole mass function, we limit the sample within the redshift range between 1.18<z<1.68. There are Broad-line AGN : with zspec 118 objects, zphot only 10 objects Narrow-line AGN : with zspec 66 objects, zphot only 92 objects

Virial Black Hole Mass Estimation with L-BLR Radius relation with L BLR Radius relation

We use the black hole mass estimation from Vestergaard & Osmer (2009) with FWHM of MgII broad emission line and 3000A monochromatic with FWHM of MgII broad-emission line and 3000A monochromatic luminosity. The relation is calibrated with reverberation mapping AGN black hole mass pp g with H-beta broad-line line width. It assumes, Luminosity ‒ BLR radius relation BLR is virialized Local MBH-Mbulge relation for AGN is consistent with MBH-Mbulge relation of galaxies “Si l h” bl k h l i h 0 4 0 5d “Signle-epoch” black hole mass estimate can have 0.4-0.5dex scatter against MBH determined with reverberation mapping.

MgII FWHM measurements

With optical spectroscopic data. (188 objects in total) 97 objects out of 118 broad-line AGNs at z=1.18-1.68 j j

Halpha FWHM with FMOS

(81 objects in total) 19 additional objects out of 21 broad-line AGNs at z=1.18- 1.68 w/o MgII FWHM measurement

Halpha FWHM

(81 objects in total) 19 additional objects out of 21 broad-line AGNs at z=1.18- 1.68 w/o MgII FWHM measurement g

FWHM vs. continuum luminosity

Broad-line AGNs in 1.18 < z <1.68 All broad-line AGNs

Broad-line AGNs in SXDS (black) and SDSS (gray scale) Red open squares indicate broad-line AGNs whose FWHM is estimated with Halpha emission line. estimated with Halpha emission line. Lack of AGNs with FWHM < 2000km/s ?

Black Hole Mass and Eddington Ratio

Plotted only broad-line AGNs in the redshift range 1.18 < z <1.68

D i li i Detection limit B d li AGN i SXDS ( i ) d SDSS ( ) Broad-line AGNs in SXDS (points) and SDSS (contour) Lack of high Eddington ratio AGNs with 10^7 Msolar ?

Active Super Massive Black Hole Mass Function

SXDS 1.18 < z <1.68 Filled and open circles are binned BHMF estimated by Vmax method with soft and hard band samples, respectively.

Eddington Ratio Distribution Function

SXDS 1.18 < z <1.68 Filled and open circles are binned ERDF estimated by Vmax method Filled and open circles are binned ERDF estimated by Vmax method with soft and hard band samples, respectively.

Active Super Massive Black Hole Mass Function

SXDS 1.18 < z <1.68 SXDS 1.18 < z <1.68 Lines are “corrected “ BHMF and ERDF from Maximum Likelihood estimation corrected for the detection limits assuming constant ERDF regardless of the black hole mass. Solid: double-power-law BHMF, Dotted: Schechter BHMF G l l RD R d S h h RD Green: log-normal ERDF, Red: Schechter ERDF

Active BHMF at z~1.4 compared with SDSS results p

SXDS 1 18 1 68 SXDS 1.18 < z <1.68 Z=1.4 SDSS DR7 (Shen & Kelly 2012) Circles: binned estimates with Vmax Circles: binned estimates with Vmax Solid lines: esimated with Bayesian method

Evolution of active BHMF from z=1.4 to z=0

SXDS 1.18 < z <1.68

Z=0 from ESO/Hamburg from Schultz-Wisotzki 2010

z~1.4 active BH mass function has a higher number density above 10^8 l b l b d b l h h h h Msoloar but a lower number density below that mass range than that in the local Universe. The evolution may be indicative of a down-sizing trend of accretion activity among the SMBH population.

Evolution of ERDF from z=1.4 to z=0

SXDS 1.18 < z <1.68

Z=0 from ESO/Hamburg from Schultz-Wisotzki 2010 Schultz-Wisotzki 2010

The evolution of ERDF from z=1.4 to z=0 indicates that the fraction of AGNs with accretion rate close to the Eddington-limit is higher at higher redshifts.

BHMF and ERDF on the MBH-ER plane

Expected number density on the MBH ER plane (BHMF x ERDF x Expected number density on the MBH-ER plane (BHMF x ERDF x selection function) is shown with gray scale.

BHMF BHMF ERDF

Detection Limit

Growth of SMBH from z=6 to z=1.4 to z=0

Z=0 from ESO/Hamburg from Schultz-Wisotzki 2010

SXDS 1.18 < z <1.68

Schultz-Wisotzki 2010 Z=6 from Willott et al 2010 Willott et al. 2010

30 times mass evolution in 3.5 Gyr period Lambda Edd * duty cycle ~ 0 06 Lambda_Edd * duty cycle ~ 0.06

What does the double power-law of the AGN LF mean ? What drives the evolution of the LF of AGNs ? What drives the evolution of the LF of AGNs ?

U d MA l i Ueda, MA, et al. in prep.

Hard X-ray luminosity function at z=1.4 Recovered by the best-fit BHMF and ERDF by the best fit BHMF and ERDF

The luminosity function of AGNs is the convolution of the BHMF and ERDF, therefore we can constrain the shapes of BHMF and ERDF further by using the luminosity function determined from a combination of various AGN samples. luminosity function determined from a combination of various AGN samples. Both of the BHMF and ERDF are modeled with an exponential-cutoff, the high luminosity end of the luminosity function cannot be reproduced.

SXDS AGNs at z=1-2

For black hole mass function, we limit the sample within the redshift range between 1.18<z<1.68. There are Broad-line AGN : with zspec 118 objects, zphot only 10 objects Narrow-line AGN : with zspec 66 objects, zphot only 92 objects, NO MBH with Broad-line FWHM

Contribution of obscured narrow-line AGNs

Among the X-ray-selected AGNs in the redshift range, more than half of the AGNs are obscured narrow-line AGNs. The contribution of these obscured narrow-line AGNs to the active binned BHMF is evaluated using the hard-band sample. BH f b d li AGN i d i BH mass of obscured narrow-line AGNs are estimated assuming constant Eddington ratio for each luminosity range.

Contribution of obscured narrow-line AGNs

Hard-band sample Black hole mass function for 2-10keV selected sample. Open circles: BHMF for broad-line AGNs only Open triangles: BHMF including contribution of obscured narrow-line AGNs. Th lid d d d d h d li i BHMF 0 1 2 f K b d The solid, dotted, and dashed lines are non-active BHMF at z=0, 1, 2 from K-band LF of galaxies (Li et al. 2011).

Summary for Nobuta et al. 2012

• z~1.4 active BH mass function shows peak at 10^8.5

Msolar, and has a higher number density above 10^8 Msoloar but a lower number density below that mass h h i h l l U i Th l i range than that in the local Universe. The evolution may be indicative of a down-sizing trend of accretion activity among the SMBH population.

• The evolution of ERDF from z=1.4 to z=0 indicates that

the fraction of AGNs with accretion rate close to the Eddington limit is higher at higher redshifts Eddington-limit is higher at higher redshifts.

• Both evolutions of the BHMF and ERDF drive the
• bserved evolution of the LF from z=1 4 to z=0
• bserved evolution of the LF from z=1.4 to z=0.
• In order to explain the double power-law shape of the

AGN LF, either BHMF or ERDF needs to be extended to AGN LF, either BHMF or ERDF needs to be extended to higher BH mass or larger ER.

• If contribution from obscured AGNs considered, the

co t but o

• bscu ed

G s co s de ed, t e fraction of active BH among entire SMBHs should be fairly high at z~1.4 (order of ~10%).

Intrinsic BHMF and ERDF

• The estimated BHMF and ERDF so far are not corrected for the

tt i th MBH ti t scatter in the MBH estimate.

• “Signle-epoch” MBH estimate can have 0.4-0.5 dex scatter.

Intrinsic BHMF and ERDF at z~1.4

If we consider the effect of the scatter of the MBH estimate; Black lines: Fitting w/o scatter of the MBH estimate Black lines: Fitting w/o scatter of the MBH estimate Blue lines: Fitting with scatter of the MBH estimate (half) Green lines: Fitting with scatter of the MBH estimate (full)

Estimation of Intrinsic BHMF and ERDF, possible degeneracy possible degeneracy

The estimation of the intrinsic BHMF and ERDF can have degeneracy.

Future

• Examine evolution of the BHMF and ERDF in the X-ray-selected

sample by E t di th t d t id d hift ( 1 18 1 68

• Extending the study to wider redshift range (z=1.18-1.68 ->

z=0.9-2.0) with broad MgII line observations in redder wavelength range (>8000A).

• Intrinsic BHMF and ERDF with obscured AGNs (~ maximum

likelihood estimation with obscured AGNs without broad-line measurements).

• Understand populations of AGNs which are missed in the X-ray

Understand populations of AGNs which are missed in the X ray surveys

• Heavily-obscured Compton-thick AGNs.
• Narrow line Seyfert 1s with very soft X ray spectrum
• Narrow-line Seyfert 1s with very soft X-ray spectrum.
• Subaru Prime-Focus Spectrograph !
• TMT in the early universe !

Thank you for your attention Thank you for your attention.

Future

• TMT for the BH statistics in the early universe !

TMT for the BH statistics in the early universe !

Deepest X-ray image by Chandra Deepest NIR image by Subaru + Optical image by HST p y g y + Optical image by HST

Evolution of Broad-line AGN BH Mass Functions from SDSS

Shen & Kelly 2012 (Kelly et al. 2009, 2010) y

SDSS sample only covers most massive BHs with high-Eddington (~1) ratio. In order to understand the AGNs dominating accretion growth of SMBHs it In order to understand the AGNs dominating accretion growth of SMBHs, it is necessary to reveal fainter AGNs (~knee of X-ray logN-logS).

Active BHMF at z~1.4 compared with SDSS results p

SXDS 1 18 1 68 SXDS 1.18 < z <1.68 Z=1.4 SDSS DR7 (Shen & Kelly 2012) Circles: binned estimates with Vmax Circles: binned estimates with Vmax Solid lines: esimated with Bayesian method

ERDF at z~1.4 Compared with SDSS

SXDS 8 68 SXDS 1.18 < z <1.68

Blue lines: SDSS DR7 (Shen & Kelly 2012)

Eddington Ratio Distribution Function

We compare the binned ERDFs in the two mass ranges 10^8.0-8.5 M l (bl ) d 10^8 5 9 0 M l ( d) N i ifi diff Msoloar (blue) and 10^8.5-9.0 Msoloar (red). No significant difference

• bserved within the uncertainty.

Active BHMF at z~1.4 compared with SDSS results p

SXDS 1 18 1 68 SXDS 1.18 < z <1.68 Z=1.4 SDSS DR7 (Shen & Kelly 2012) SDSS DR7 (Shen & Kelly 2012) Circles: binned estimates with Vmax Solid lines: esimated with Bayesian method