Movies of Numerical Relativity Simulations (last update Dec. 2023)
created by Kenta Kiuchi, Kota Hayashi, Alexis Reboul-Salze, and Tomohide Wada.


1. Alpha-Omega dynamo in binary neutron star merger (2023)

Fully general relativistic neutrino-radiation transfer magnetohydrodynamic simulation performed on the CRA cluser SAKURA and the Japanese supercomputer FUGAKU.
DD2 equation of state (S. Banik, M. Hempel, and D. Bandyopadhyay, 2014), symmetric binary of 1.35 solar mass and 1.35 solar mass, and 12.5 meter resolution.



Magnetic-field line and rest-mass density iso-surface for the merger remnant.

3D visualization
Meridional-cut visualization
Dynamo wave propagation (Mean toroidal field)
Mean poloidal field generation

Ref.) Kenta Kiuchi, Alexis Reboul-Salze, Masaru Shibata, and Yuichiro Sekiguchi, Nature Astronomy (2023)


2. One second-long simulation of binary neutron star merger (2023)

Fully general relativistic neutrino-radiation transfer magnetohydrodynamic simulation performed on the Japanese supercomputer FUGAKU.
Equation of state is SFHo (A. W. Steiner, M. Hempel, and T. Fisher 2013), and asymmetric binary of 1.2 solar mass and 1.5 solar mass.



Density, magnetic-field strength, magnetization parameter, Bernoulli criterion, electron fraction, temperature, specific entropy, and Shakura-Sunyaev profile on a meridional plane.

3D visualization
Meridional-cut visualization

Ref.) Kenta Kiuchi, Sho Fujibayashi, Kota Hayashi, Koutarou Kyutoku, Yuichiro Sekiguchi, and Masaru Shibata, PRL 131, 011401 (2023)


3. Highest resolution simulation of binary magnetized neutron star merger (2014)
General relativistic magnetohydrodynamics and fixed mesh refinement are implemented.
Equation of state is H4 (N. K. Glendenning and S. A. Moszkowski 1991) and total mass is 2.7 solar mass.
The finest resolution is 70 and 110 meter and the simulation has been performed on the Japanese supercomputer K.


Density iso-surface with the magnetic field lines.
The dark blue represents 10^10 g/cc and light blue does 10^10.5 g/cc.
The black hole resides at the center.
Animation (110m 120 MB)
Animation (70m 120 MB)

Ref.) Kenta Kiuchi, Koutarou Kyutoku, Yuichiro Sekiguchi, Masaru Shibata, and Tomohide Wade, PRD 90, 041502 (R) (2014)


4. Highest resolution simulation of black hole-magnetized neutron star merger simulation (2015)
General relativistic magnetohydrodynamics and fixed mesh refinement algorithm are implemented.
Equation of state, neutron star mass, mass ratio of BH to NS, and, BH spin are APR4, 1.35 solar mass, 4, and 0.75, respectively.
The finest resolution is 120 meter and the number of the grid point is 1028×1028×1028 in a refinement level.
The simulation has been performed on the Japanese supercomputer K.


Density iso-surface after tidal disruption.
Yellow, green, and blue color represent 10^11, 10^10, and 10^9 g/cc, respectively.
Animation for density (49 MB)
Animation for B-fields (49 MB)

Ref.) Kenta Kiuchi, Yuichiro Sekiguchi, Koutarou Kyutoku, Masaru Shibata, Keisuke Taniguchi, and Tomohide Wade, PRD, 92, no. 6, 064034 (2015)


5. Kelvin-Helmholtz instability in binary neutron star merger (2015)
Equation of state is H4 (N. K. Glendenning and S. A. Moszkowski 1991) and total mass is 2.8 solar mass.
The finest resolution is 17.5 meter and the number of the grid point is 1024×1024×512 in a refinement level.
The simulation has been performed on the Japanese supercomputer K.


Contact interface at the merger.

Animation for density field with 17.5 m resolution (38 MB)
Animation for density field with 37.5 m resolution (38 MB)
Animation for density field with 75 m resolution (38 MB)
Animation for density field with 150 m resolution (38 MB)


Ref.) Kenta Kiuchi, Pablo Cerda-Duran, Koutarou Kyutoku, Yuichiro Sekiguchi, and Masaru Shibata, PRD, 92, no. 12, 124034 (2015)


6. Magnetohydrodynamics-driven turbulence in a binary neutron star merger (2018)
Equation of state is H4 (N. K. Glendenning and S. A. Moszkowski 1991) and total mass is 2.5 solar mass.
The finest resolution is 12.5 meter and the number of the grid point is 1404×1404×702 in a refinement level.
The simulation has been performed on the Japanese supercomputer K.


Animation for density field and magnetic field with 70 m resolution (121 MB)


Ref.) Kenta Kiuchi, Koutarou Kyutoku, Yuichiro Sekiguchi, and Masaru Shibata, PRD, 97, no. 12, 124039 (2018) (selected as Editor's suggession)



7. Revisiting the lower bound of tidal deformability derived by AT 2017gfo (2019)
Equation of state is (log P, M_{max})=(34.2, 2.00 Solar mass) and 1.2 Solar mass -1.55 Solar mass asymetric binary.



Animation for density field

Minimum value of the lapse function

Ref.) Kenta Kiuchi, Koutarou Kyutoku, Masaru Shibata and Keisuke Taniguchi, ApJ 876 L31 (2019).