Gallery: Binary, inspiraling neutron stars forming a hypermassive neutron star

This simulation shows how to evolve a pair of neutron stars, reading in initial data provided by the LORENE code. The video shows the rest mass density in an equatorial slice of the simulation. The emitted gravitational waves of the inspiral and due to the oscillations in the formed hypermassive neutron star are shown as well.

Parameter file bns.par
Thornlist bns.th

This thornlist contains the thorns of the Einstein Toolkit as well as the thorn NSTracker which is not part of the Einstein Toolkit yet.

Steps:

  1. ./GetComponents --root BNS http://einsteintoolkit.org/gallery/bns/bns.th for the latest release (or
    ./GetComponents --root BNS http://einsteintoolkit.org/gallery/bns/bns-master.th to pull from the top of master)
  2. cd BNS
  3. curl -LO https://einsteintoolkit.org/gallery/bns/bns.par
  4. ./utils/Scripts/MakeThornList -o bns.th --master thornlists/bns.th bns.par (or
    5. ./utils/Scripts/MakeThornList -o bns.th --master thornlists/bns-master.th bns.par)
  5. ./simfactory/bin/sim setup-silent
    At this point you may have to edit ./simfactor/etc/defs.local.ini to enter the allocation name.
  6. ./simfactory/bin/sim build --thornlist bns.th
  7. ./simfactory/bin/sim create-submit bns --parfile bns.par --procs=128 --num-threads=4 --walltime=70:00:00
    Using this command it took approximately 30 hours to run on Frontera.
  8. curl -LO https://einsteintoolkit.org/gallery/bns/scripts.tar.gz
  9. tar -xvf scripts.tar.gz
  10. python3 scripts/mp_Psi4_l2_m2_r300.00.py "path"
    Note that "path" here is the full path to the output directory containing the data.
Initial data file G2_I12vs12_D4R33T21_45km.resu.xz

Uncompress using unxz. Sample ID is taken from LORENE

Support scripts scripts.tar.gz
approx. memory 64 GB
approx. runtime 30 hours using 4 nodes, 56 cores per node
Results (86MB) bns-20241124.tar.gz

This example was last tested on 24-November-2024.



Psi_4^{2,2} at r=300M over time