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Thanks to our sponsor. M. Aller (UM) R. Bender (Munich) G. Bower (NOAO) A. Dressler (OCIW) S. Faber (UCSC) A. Filippenko (UCB) K. Gebhardt (Texas) R.Green (NOAO) L. Ho (OCIW). T. Lauer (NOAO) J. Kormendy (Texas) J. Magorrian (C U) J. Pinkney (Michigan) D. Richstone (Mich)
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M. Aller (UM) R. Bender (Munich) G. Bower (NOAO) A. Dressler (OCIW) S. Faber (UCSC) A. Filippenko (UCB) K. Gebhardt (Texas) R.Green (NOAO) L. Ho (OCIW) • T. Lauer (NOAO) • J. Kormendy (Texas) • J. Magorrian (C U) • J. Pinkney (Michigan) • D. Richstone (Mich) • C. Siopis (Mich) • S. Tremaine (Princeton)
Weighing planets, stars, galaxies or black holes vcirc = aGM/r a depends on the orbit
Orbit Superposition (Schwarzschild’s method) • Assume a mass distribution. • Compute the gravitational forces. • Follow all the orbits. • Sum the orbits to match the observed velocities. • Failure rules out the mass distribution.
Results of 15 year effort • Most bulges have BH (97% so far). • BH mass tracks main-body parameters (L, ).
Bulge M/L ~ 3x10-3h • Density - 2.5x105 Msun/Mpc³ for h=.65 (Yu & Tremaine) - 4.8x105h² Msun/Mpc³ (Aller & Richstone) • consistent results from different datasets. • S = 2.2x105 Msun/Mpc3 - 6 – 9x105 (Fabian & Iwasawa) qso+X-ray background (and similar from Barger).
?BIG PROBLEM? The X-ray background energy exceeds the available sources of energy in known supermassive black holes. (the known population of SBH seems just adequate for the quasar energy).
A note on backgrounds • Any background can be expressed in terms of the cosmic microwave background energy density (about 1eV/cm3). • uqso ~ 10-4 • bh ~ uqso-1(1 - -gw – ejections) • ustars ~ 1
What should theorists learn from the observations? • BH can accrete stars, gas, degenerate objects, dark matter; only gas accretion yields the correct Soltan number. • Most BH growth has occurred during the quasar epoch. Is this also the epoch of bulge formation? Of major mergers? • How does BH growth connect to galaxy formation and evolution?
Ideas for the M-s4 relation in the context of collapse or evolution • The bh growth is limited by a mass budget - competition w/ star formation(Burkert & Silk). • BH growth limited by energy conservation (Silk & Rees, Blandford, A.R.King). Ciotti & Ostriker, pure core collapse). • The bh growth is limited by a momentum budget (Fabian) • BH growth is limited by angular-momentum (AGR).
Feedback versus initial conditions • Most feedback models are likely to eject material only in certain directions (for example, bubble break-out along direction of fastest density gradient). • Condition dependent models are fragile against changes in the environment.
Any initial formation mechanisim evolves through the merger hierarchy (investigated through SAMs by Haehnelt & Kaufman). • BH merge or form binaries, triples, etc. • Ejections? The “last parsec” problem? • The dispersion of the M- relation is an important clue.
Implications • BH growth spurt during quasar era (is this the epoch of bulge formation?). • What is the pedigree of BH and galaxies? • M- relation is a powerful clue. • Co-Evolution! --- feeding, bar disruption, core scouring, mergers --- bh growh connected to galaxy evolution.