# Evolution of Matter and Magnetic Fields

Plots of surface density profile $\Sigma(R)$ and disk scale height $H/R$ vs. cylindrical coordinate radius $R$ for the three disk models.

## Case A: Large Disk

We follow the evolution of the matter and magnetic fields of a gaseous disk. In the cavity of the disk are two black holes, with a mass ratio of $q = 36:29$. Green lines depict magnetic field lines within the disk. The seeding points used in drawing these fields lines were taken from a subset of fluid test-particles that were evolved during the simulation. By drawing magnetic field lines from these test-particles, we can visualize the evolution of the magnetic field lines, because they are attached ("frozen in") to the same particles for all time. White lines highlight the field lines threading the polar regions above the black holes. These field lines are drawn from fixed grid points above each black hole pole.

In this case, the disk has inner radius of $R_{in}/M = 20$, an outer radius of $R_{out}/M = 250$, and maximum height-to-radius ratio of $(H/R)_{max} = 0.33$. The color bar denotes the rest-mass density in the disk normalized to the initial maximum disk density

Following merger, the twin jets merge and the black hole remnant aquires a spin of $a/M \approx 0.68$. Quasistationary accretion onto the black hole is established as well as an outgoing jet that is confined and driven by a helical, tightly wound magnetic field emerging from the black hole poles. The jet carries an EM (Poynting) luminosity consistent with the Blandford-Znajek mechanism.

In this simulation the gravitational field is evolved by solving the Einstein field equations via the BSSN formalism and the matter and magnetic fields are evolved by solving the equations of GRMHD via a high-resolution shock capturing scheme.

 Fig. 1-1: Inital Configuration Fig. 1-2: Twin jets rise from the inspiraling black holes Fig. 1-3: Zoom in to central cavity
 Fig. 1-4: Post merger black hole and magnetic field Fig. 1-5: Quasistationary jet outflow
Play Case A

## Case B: Medium Disk

In this case, the disk has inner radius of $R_{in}/M = 20$, an outer radius of $R_{out}/M = 100$, and maximum height-to-radius ratio of $(H/R)_{max} = 0.22$.

 Fig. 2-1: Inital Configuration Fig. 2-2: Twin jets rise from the inspiraling black holes Fig. 2-3: Zoom in to central cavity
 Fig. 2-4: Post merger black hole and magnetic field Fig. 2-5: Quasistationary jet outflow
Play Case B

## Case C: Small Disk

In this case, the disk has inner radius of $R_{in}/M = 20$, an outer radius of $R_{out}/M = 60$, and maximum height-to-radius ratio of $(H/R)_{max} = 0.14$.

 Fig. 3-1: Inital Configuration Fig. 3-2: Dual jets rise from the inspiraling black holes Fig. 3-3: Zoom in to central cavity
 Fig. 3-4: Post merger black hole and magnetic field Fig. 3-5: Quasistationary jet outflow
Play Case C