The BHCOSMO: Simulating black hole and galaxy formation along cosmic time


The BHCosmo run includes a quater of a billion particles to trace the evolution of the dark and visible matter
distribution in a cubic region of the universe over 100 million light years. The simulation was run on 2000 CPUs
at the Pittsburgh Supercomputing Center (PSC).

For the First Time Black Hole growth and associated feedback is included in a Large-Scale Cosmological Simulations.

The simulations self-consistently computes gravity exerted by dark matter, the unseen material that comprises ninety percent of the
universe and the forces associated with various cosmic phenomena, including cooling gas, growing black holes, and exploding stars.

Pictures of the matter and black hole distribution:

The projected gas density distribution and the black holes (shown as yellow circles) in a slice of the simulation box at
seven different redshifts. Top left, the universe is 300,000 million years old, the first black holes emerge. As the universe
evolves (from top left to bottom right) supermassive black holes and large galaxies form at the intersection of large
scale matter filaments.  The bottom, righ-hand panel shows the  gas  distribution at z=1, without the black holes.


Movies of the Simulation

A 3D visualization of the galaxies, which host the supermassive black holes, in the BHCosmo run. The movie shows a journey
 through the stellar, visible matter in the simulated universe.  We fly toward the most massive galaxy in the simulation, at the
center of which the most massive black hole resides (not explicitly shown in this movie).


2. Spiraling around the BH host galaxy

3. The evolution of the gas density distribution

4. Zooming into a quasar host

The gas and stellar distribution, illustrating the dynamic range of the BHCosmo simulation

The following images show the projected gas density field and the black holes at z=3.


Below are  overlaid panels zooming in by a factor of 4, enalarging the region indicated by the white square above.
Yardsticks are indicated in each panel.

                                             Gas                                                                                 Stars


1. Tiziana Di Matteo, Joerg Colberg , Volker Springel , Lars Hernquist, Debora Sijacki                                                        
      Direct cosmological simulations of the growth of black holes and galaxies
2008, ApJ, 676, p.33

2. Debora Sijacki, Volker Springel, Tiziana Di Matteo , Lars Hernquist
    A unified model for AGN feedback in cosmological simulations of structure formation, 2007, MNRAS, 380, p.877