Super Massive Black Holes

The Unknown Astrophysics of their initial formation

Characteristics of SBMHCrit = light cone loss

A = accretion radius

Coll = stellar disruption radius

E = eddington radius; radiation pressure limits accretion; more efficient with larger G

T = tidal radius

G = Event horzon

Important: When G>T no energy can be emitted; quenching mechanism

Evidence for SBMHEvidence for SBMH

Perturbed orbits at Galaxy Center

Only physically plausible Mechanism for observedQuasar Luminosity

Evidence for SMBHEvidence for SMBH

Only plausible QSO Power SourceOnly plausible QSO Power Source

Much of the Gravitational Infall Energy is converted to Magnetic Field energy and the subsequent production of relativistic particles in what are called Radio Loud QSO.

This Conversion process remains mysterious.

Simple BH Growth by AccretionSimple BH Growth by Accretion

Tidal break up of star requires energy: ETidal break up of star requires energy: Ebb = 3/4 G m = 3/4 G m22/R /R

Orbit of gas radius is: Orbit of gas radius is:

Our galaxy @ 2x10Our galaxy @ 2x106 6 M ; RM ; Rgasgas =10 =101212 km km well outside the event well outside the event horizon of a black hole so it will take a long time to fall from that horizon of a black hole so it will take a long time to fall from that initial radius throw some in spiral process. Suggests slow growth.initial radius throw some in spiral process. Suggests slow growth.

Maximum accretion rate dictated by Eddington Luminosity (radiation Maximum accretion rate dictated by Eddington Luminosity (radiation pressure limited) pressure limited) Under typical eddington conditions growth rate Under typical eddington conditions growth rate is Te= 9.3 x10is Te= 9.3 x1077 ln(Mc/M) yr ln(Mc/M) yr linear approx: 1 M per 10 years. linear approx: 1 M per 10 years.

Time for 1 solar mass to 10Time for 1 solar mass to 1088 solar masses is then 2 Gigayears solar masses is then 2 GigayearsPredicts QSO emergence Z at z = 2.5Predicts QSO emergence Z at z = 2.5Z=8 QSO = 500 million years at maximum growth rateZ=8 QSO = 500 million years at maximum growth rate

Density Limited AccretionDensity Limited Accretion

This maximum rate, however, is not realistic, This maximum rate, however, is not realistic, since the black hole quickly depletes its since the black hole quickly depletes its environment. environment.

Its not at all clear that this depletion can Its not at all clear that this depletion can replenishes itself rapidly with new materialreplenishes itself rapidly with new material

Then growth rate is limited by density. DM/dt = Then growth rate is limited by density. DM/dt = V The corresponding time-scale to grow from V The corresponding time-scale to grow from M to Mc under these conditions is at least 5 GYrM to Mc under these conditions is at least 5 GYrSMBH growth can not occur nearly fast SMBH growth can not occur nearly fast enough under either of these conditionsenough under either of these conditions

Binary StarsBinary Stars

New studies show that binary stars New studies show that binary stars are captured more efficiently; at are captured more efficiently; at least one gets disruptedleast one gets disrupted

But is the seed population big But is the seed population big enough?enough?Binary Stars might

not easily form in the first generation of stars at high redshift.

Possibilities

Population III Stars: Collapse of Gas Clouds Collapse of Stellar Clusters Merger of already well formed galaxies

Population III Stars

What if you start with 104 solar masses to begin with.

Growth time is then 800 million years; still not fast enough

Mergers of 100 seeds to 106 solar masses Growth time is then 400 million years

But this require seeds to exist at z > 100 Very Unlikely Scenario

Wind = Yellow

A simulated formation model

Part of Galaxy Formation Part of Galaxy Formation Process?Process?

We find that most copiously accreting black We find that most copiously accreting black holes at these epochs are buried in holes at these epochs are buried in significant amounts of gas and dust that significant amounts of gas and dust that absorb most radiation except for the absorb most radiation except for the highest-energy X-rays. This suggests that highest-energy X-rays. This suggests that black holes grew significantly more during black holes grew significantly more during these early bursts than was previously these early bursts than was previously thought, but because of the obscuration of thought, but because of the obscuration of their ultraviolet emission they did not their ultraviolet emission they did not contribute to re-ionization.contribute to re-ionization.

Where does all the dust/gas come from?Where does all the dust/gas come from?

Galaxy interactions accelerate the growth of Galaxy interactions accelerate the growth of supermassive black holessupermassive black holes

Okay, yes, we observe this going on Okay, yes, we observe this going on Now via merger induced accretion of Now via merger induced accretion of by now pretty large galaxies by now pretty large galaxies not not likely applicable in the first 1 billion likely applicable in the first 1 billion yearsyears

Outflow Limited CollapseOutflow Limited Collapse

Basic gas physics suggests that Basic gas physics suggests that collapses slows (greatly) with collapses slows (greatly) with feedback from when the first stars feedback from when the first stars form. form. Mass outflows from massive

stars have to make everything take longer to form and settle. In some cases – terminal galaxy formation can ensue

The right input physics into these simulations is not well known

Monolithic Galaxy FormationMonolithic Galaxy Formation

Something that doesn’t happen Something that doesn’t happen easily in the DM Universeeasily in the DM Universe

Massive spheroid Galaxies may have Massive spheroid Galaxies may have 101088 to 10 to 109 9 solar mass dusty tori solar mass dusty tori within 100 pc of galaxy center. within 100 pc of galaxy center.

But this happens at Z=2 not Z=9But this happens at Z=2 not Z=9Z=2 sources can be detected with Z=2 sources can be detected with

ALMAALMA

In sum: All known growth processes are too slow to account for existence of radiating SMBH at z =8.

Therefore a special/unknown process is required; likely means there is electromagnetic radiation emitted by sources at z > 100

Are there remnants of these sources in the nearby Universe?