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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. Local BH Mass Functions. Galaxy luminosity function→BH mass function Primary mode of BH growth
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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 Local BH Mass Functions Galaxy luminosity function→BH mass function Primary mode of BH growth AGN lifetimes, radiative efficiency
Broad-line AGNs - masses from AGN physics - compare broad and narrow line AGNs - sensitive to low-mass (<106M⦿) BHs Heckman et al. 2004 Narrow-line AGNs Distribution of L[OIII] All BHs (active+inactive) BHs Growing Today
Only means to probe this regime is using AGNs, since current resolution inadequate for dynamical detection But isn’t this a neglible fraction of total BH mass and radiated lumiminosity? Haehnelt 2004
Bromm & Loeb Merritt et al. 2004 E LISA dE dSph GC Primordial Seeds Gravitational Recoil Disproportionate Import Gravitational radiation
Stellar Mass Low-mass BHs are rare? Greene & Ho 2004 found only 19 broad-line AGNs in DR1 (<106M⦿) All galaxies Active galaxies (narrow-line) Groves et al. astroph/0607311
PCA (Hao et al. 2005) [S II] λλ6716, 6731 Hα + [N II] λλ6548, 6583 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 Modeling (Greene & Ho 2004)
Greene & Ho 2005 Standard scaling relations (BLR radius and AGN luminosity) ~8000 AGNs, 2000 from main galaxy sample MBH Lbol/LEdd FWHMHα LHα
Greene & Ho in prep Lbol/LEdd 0.01 0.03 0.1 0.3 1 Greene & Ho in prep SDSS bright limit
Ho 2004 broad Hα luminosity function 8300 broad-line AGNs Vmax method Hα Luminosity Function Greene & Ho in prep Contaminants
? * MBH “Cosmic Downsizing” BH Mass Functions Greene & Ho in prep Text
CF with Hasinger et al 2005 Soft X-ray LF Inferred from optical using αox All T2s from SDSS Broad-line AGNs Seyfert T2s Greene & Ho in prep CF with Heckman et al. 2004
Real turnover at the low-mass end OR low-mass BHs are quiescent OR incorrect galaxy luminosities z=0.05 z < 0.02 z =0.1 0.01 < L/LEdd<0.1 0.1 < L/LEdd<0.3 0.3< L/LEdd<3 5 6 7 8 9 5 6 7 8 9 5 6 7 8 9 log (MBH/M⦿) Monte Carlo
3 kpc GH08 GH05 8 kpc GH02 7 kpc GH17 GH04 GH09 4 kpc 20 kpc 10 kpc 19 AGNs (<106M⦿) Greene & Ho 2004HST/ACS: F435W (B), F814W (I), 1 orbit/source Greene, Barth, & Ho in prep 7 kpc
5 mag Barth, Greene, & Ho 2005 MBH-LBulge Marconi & Hunt (2003) Greene & Ho 2004 Pox 52 NGC 4395 GALFIT Peng et al. 2002 PSF + 1 Sersic fit Barth et al. 2004 Filippenko & Ho 2003 Greene, Barth, & Ho in prep
Lauer et al. 2006/astroph0606739 Ferrarese 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 (<106M⦿) • 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)
5 mag MBH-LBulge Marconi & Hunt (2003) Greene & Ho 2004 Pox 52 NGC 4395 GALFIT Peng et al. 2002 PSF + 1 Sersic fit Barth et al. 2004 Filippenko & Ho 2003 Greene, Barth, & Ho in prep
M87G N 2787G N 3608 N 4291 N 4459g N 4649 N 4596g N 3245 N 6251g IC 1459 N 7052g N 2778 N 1023 N 3384 N 3377 N 821 N 4697 N 3379 N 4473 N 3115 N 4564 M 32 M31 MW N 7457 N 4258m N 1068m N 4261 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
z=0.02 z=0.05 z=0.1 Bulge/Total ratio poorly constrained for low-mass BHs Lbol/LEdd = 0.01 Lbol/LEdd = 0.1 Lbol/LEdd = 1
z=0.05 Real incompleteness at the low-mass end OR biased galaxy sample OR low-mass BHs are quiescent z=0.02 z=0.1 L/LEdd=0.01 L/LEdd=0.1 L/LEdd=1 4 6 8 4 6 8 4 6 8 log (MBH/M⦿)
Which BHs are growingToday? Narrow-line AGNs SDSS Galaxies Heckman et al. 2004