Black Holes and the Evolution of Galaxies…

Summary Quasars and Evolution: the universe becomes interesting How we do it: things invisible to see. Demographics: the inverse dinosaur problem. –M-  relation, bh mass spectrum. Emerging developments – –The energy budget for galaxy formation –Extension to very low masses –spins –Possibility of gravitational wave observation of BH mergers.

In 1963 the universe became more interesting Quasars Evolution The initial conditions

3c175

Universe baby picture: WMAP 5 year image.

Mysterious properties of quasistellar objects Rapid variability – minutes. –Light travel time across inner solar system. Directed energy output (collimated beams of high-energy particles. “Superluminal” motion. Enormous luminosities ~ suns. Objects the size of the solar system that outshine the galaxy. Quasars were populous in the youthful universe, but are rare now.

Quasars and Black Holes Small size, large luminosity and apparent stability suggest that quasars are gravity powered. Ultimate gravitational engine is a bh. Some fraction of accreted energy is radiated (can greatly exceed thermonuclear energy). BH turns off when fuel is cut off.

Inverse dinosaur problem The light radiated by quasars is proportional to mc 2 of accreted matter. The mass of order m of the accreted matter. The density of quasars mandates a density of bh of about 2 x 10 5 solar masses/Mpc 3. Where are the relics?

Cavendish experiment

M84

Orbit Superposition (Schwarzschild’s method) Assume a mass distribution (light + BH). Compute the gravitational forces. Follow all the orbits. Sum the orbits to match the observed light distribution and velocities. Failure rules out the mass distribution.

Results of 20 year effort Most bulges have BH (97% so far). BH mass tracks main-body parameters (L,  ).

Gultekin et al.

Aller & Richstone

Bulge M/L ~ 3x10 -3 h Density - 2.5x10 5 Msun/Mpc -3 for h=.65 (Yu & Tremaine) - 4.8x10 5 h 2 Msun/Mpc -3 (Aller & Richstone) -consistent results from different datasets. -S = 2.2x10 5 M sun /Mpc 3

Only gas will produce the correct Soltan number Accreting matter: –Stars –Degenerate objects –Dark matter –Gas

Implications BH growth spurt during quasar era (is this the epoch of bulge formation?). –What is the pedigree of BH and galaxies? Co-Evolution! --- feeding, bar disruption, core scouring, mergers --- bh growh connected to galaxy evolution. Is any of this observable?

Thermodynamics of the protogalaxy QSO emits Xrays: 0.1*m.c 2 in 10 8 yr Galaxy has stars: 0.01*Mc 2 in yr QSO light/starlight ~ 10 3 m./M ~ 1 bh is as important as stars in early phases of galaxy. Some fraction of BH luminosity is mechanical - may be sufficient to blow gas out of galaxy.