Black Holes Accretion vs Galaxy Properties Angela Bongiorno
Black Holes Accretion vs Galaxy Properties Angela Bongiorno Max-Planck-Institut für extraterrestrische Physik, Garching, GERMANY Cols: A. Merloni, G. Zamorani, M. Brusa, D. Vergani et al. Honolulu, June 9 th 2010
EVOLUTIONARY SCENARIO Gas inflow Normal galaxies Starburst & buried Quasar Growth of SMBH Hierarchical growth Galaxy mergers AGN feedback Active Quasar (adapted from Hopkins et al. , 2008)
Fraction of Obscured AGN vs L and z 0. 15<z<0. 3<z<0. 45 0. 5<z<0. 9 SDSS (Reyes 08) z. COSMOS • at L[OIII] > Lc, decreasing fraction of type– 2 AGN with luminosity ü 0. 15< z <0. 3 from ∼ 65% to ∼ 50% from L[O III]=106. 2 -108. 2 L to 108. 2 -109. 2 L ü 0. 3< z <0. 45 and 0. 5< z <0. 92 from ∼ 80% to ∼ 25% from L[O III =106. 2 -108. 5 L⊙ to L[O III]=109. 0 -109. 6 L ⊙ • What happen at L[OIII] < Lc? (Bongiorno, Mignoli, Zamorani et al. , 2010 A&A 510, 56 B)
BH accretion as a function of galaxy properties… SDSS type-2 AGN sample @z<0. 3 (Kauffmann & Heckman 2008) Eddington Log(L[OIII]/MBH) =1. 7 ~2% Edd Feast: Galaxies rich in cold gas ; BH growth is regulated by small-scale feedback. Famine: Galaxies poor in cold gas. BH accretes ~0. 3% - 1% of the mass lost by evolved bulge stars.
BH accretion and star formation… at higher redshift using the 20 k z. COSMOS type-2 AGN sample 392 sources @ z~1 (close to the peak of the cosmic AGN and star formation density) ➤ AGN hosts masses through SED fitting Separate the Spectral Energy Distribution of AGN into nuclear+host components and derive the host properties • AGN templates: - Elvis et al. (1994) - E(b-v)=0 - 0. 3 in 0. 01 steps • Galaxy templates: - 14 phenomenological from Polletta (2007) - Libr. of synthetic sp. (Bruzual & Charlot) a) 10 declining SFH SFR e-t/ =[0. 1 -30] Gyr tage=[50 Myr-5 Gyr] tage<tuniv(z) 0 < E(B-V) <0. 5 b) 1 constant SF Red/Purple: Galaxy template Blue: AGN template Used Bands 6 SUBARU bands K band (CFHT) 4 Spitzer/IRAC 24 m Spitzer/MIPS (Merloni, Bongiorno et al. 2010 Ap. J 708, 137 M)
BH accretion and star formation… at higher redshift ➤ Computation of the BH Masses SED fitting M* (scaling relation) BH masses (150) ~0. 2%Edd ~1. 5%Edd ( Bongiorno, Merloni et al. in prep)
Using the s. SFR to distinguish “old” and “young” galaxies (391) ~0. 02%Edd ~0. 6%Edd ( Bongiorno, Merloni et al. in prep)
Using the s. SFR to distinguish “old” and “young” galaxies Dotted lines: [OIII] completeness limit Gradual trend towards lower Eddington ratios with older stellar population content. However … selection effect still to be fully accounted for… ( Bongiorno, Merloni et al. in prep)
- Slides: 8