Making Black Holes - Early black hole formation scenarios - Connect with Star Formation? With: Matthew Turk, John Wise, Jeff Oishi, Ji-hoon Kim, Peng Simulation: John Wise & Tom Abel 2011 Visualization: Ralf Kähler & Abel (KIPAC) Wang, Marcelo Alvarez. Vis: Ralf Kaehler Tom Abel Kavli Institute for Particle Astrophysics and Cosmology SLAC National Accelerator Laboratory & Physics Department, Stanford University
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Accessible to direct First Black simulations in hydrodynamic Holes and MHD limits Dynamic range > 1e10 + subgrid modeling Accessible to direct simulations in An old subject N-body limit > 1e6 particles which modern simulations are poised to make substantial progress on. Numerical Relativity Martin Rees 1980
Do the first black holes grow rapidly? Insignificant BH accretion - no mini quasars because of internal photo- evaporation, nor pre-cursors of Quasars, large local feedback. solid: with radiation feedback dotted without feedback Alvarez, Wise & Abel ApJL, 2008
Yes! But how about the small seeds falling into rapidly growing galaxies. Surely they must grow then, isn’t it? • Same initial conditions as “Simulation B” of Wise et al (2008abcd…) – 1.5 Mpc periodic box – 1024 3 effective resoltution – 0.3 pc resolution – H 2 chemistry, pop III and pop II star formation, full radiative transfer, – First star forms at z~30 – Ionizing radiation from 100 M ¤ stars coupled to hydro – Remnant black hole accretion and radiative feedback treated including secondary ionization Alvarez, Wise & Abel (2009) ~6 kpc proper
z=8.2 still no further growth. Halo: 2 ⨉ 10 8 solar mass 3 solar masses total on 25 black holes x (kpc) x (kpc) 0 0 . 5 1 1 . 5 0 2 0 . 5 1 1 . 5 2 2 2 2 · 10 4 10 − 22 1 . 5 1 . 5 Temperature(K) Density(g / cm 3 ) 10 − 23 z (kpc) z (kpc) 1 · 10 4 1 1 10 − 24 10 − 25 0 . 5 0 . 5 5 · 10 3 10 − 26 0 2 0 2 1 · 10 − 4 0 . 5 5 · 10 − 5 1 . 5 1 . 5 0 . 2 ElectronFraction 2 · 10 − 5 H2IFraction 1 · 10 − 5 z (kpc) z (kpc) 0 . 1 1 1 5 · 10 − 6 0 . 05 2 · 10 − 6 0 . 5 0 . 5 0 . 02 1 · 10 − 6 5 · 10 − 7 0 . 01 0 0
Black holes spend almost all their time in the wrong places age of universe 500 pc
Most Pop III stellar seed black holes do not grow. • Only need to make one bright high-z quasar per comoving Gpc. So only one of hundreds of thousands potential pop III remnant black holes has to experience runaway growth. • Why that one? • How does kpc scale gas know to keep being available for accretion onto it? 500 pc Wise, Alvarez, Abel in prep.
SMBH from direct gaseous collapse? • Perhaps some halos with 10 4 K can have central cores that collapse directly? (e.g. Koushiappas et al. 2004; Volonteri & Rees 2005; Begelman et al 2006; Spaans & Silk 2006; Lodato & Natarajan 2006; Wise & Abel 2007; Regan & Haehnelt 2008) • Numerical experiment • Assume no molecules can be formed (actually very bad assumption ...) • Only H, He cooling leads to the first cooling objects to be ~ 1e8 solar masses which have a central 1e5 solar mass cloud contract fast. • See it as a numerical experiment to study the collapse of a turbulent isothermal cloud formed form cosmological initial conditions • Interesting also as a model to start studying the role of turbulence in galaxy formation • Dynamic range of 10 15 which is by far the highest resolution simulation carried out. Beat our own record by 5 orders of magnitude ... • Wise, Turk & Abel (2008), ApJ, 682, 745
Wise, Turk & Abel 2008, ApJ
Bars within Bars (and disks) are misaligned • Turbulent viscosity su ffi cient. • Angular momentum may be transported quickly. • Is this scenario realized when halo forms next to a bright source? (Shang, Bryan & Haiman 2010) • Lyman Werner band H 2 dissociation so strong that during collapse no molecules can form • Need to have such a high flux for the entire time the progenitors grow from 10 5 to 10 8 solar mass.
NGC1333 in Perseus
Box size: 2 pc Numerical experiments: Model Setup - Spherical cloud with total mass = 1200 Msun with total of 1641 Msun in the box and density profile: - c s = 0.265 km/s (T=20 K); - Initial turbulence has k -2 Burger’s power spectrum with M=9 Turbulence Magnetic Wind - Uniform magnetic field in z direction. field Mass-to-flux ratio: overall: 1.4; Base 0 0 No central: 3.3. virial 0 No HD - Sink particles to model star formation designed to give more or less the known virial 1e-4 G No MHD answer Wind virial 1e-4 G Yes - Protostellar outflow feedback. Wind/Hydro virial 0 Yes - Top grid 128^3, 4 levels of refinement by 2, maximum resolution 100 AU 2048 dynamic range . Wang, Li, Abel, Nakamura 2010 ApJ
Formation of a Star Cluster in the Milky Way Sim: Wang, Abel, Li, Nakamura 2009 Viz : Kähler, Wang & Abel 2009 Log of column density: blue-white yellow: kinetic energy - jets from young stars
Relevant physics in star formation • Hydro/MHD models form stars much Hydro to quickly and very accelerated ... +Turbulence • With proto-stellar outflows and MHD one gets const. star formation rate +MHD Total Stellar Mass • Winds keep turbulence allow cloud to form stars for many dynamical times +winds • First Model with sustained star formation over many dynamical times without large scale driving • “primordial” turbulence decays fast, most of the mass of a star cluster is built during outflow-driven turbulence phase. • Our models still are missing Time in Myr • ambipolar di ff usion Wang, Li, Abel, Nakamura 2010 ApJ • IR radiation turbulence + winds (no MHD)
| ⇤ � ⇥ B |
Summary • B-fields are amplified from the start. Relevant on small scales quickly. Viscous scale, Reynolds number and small scale dissipation are a ff ected first. • Radiation and supernovae feedback severe for early small galaxies. • Early black holes barely grow. • Key in evaluating whether the direct collapse scenario is viable will be to simultaneously and believably model star formation. • The absence of Star Formation that allows/ enables super massive black hole formation remains poorly understood. • At the same we have amazing codes now. How can we use them to make progress?
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