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


  1. ./GetComponents --root BNS for the latest release (or
    ./GetComponents --root BNS to pull from the top of maaster)
  2. cd BNS
  3. curl -LO
  4. ./utils/Scripts/MakeThornList -o --master thornlists/ bns.par (or
  5. ./utils/Scripts/MakeThornList -o --master thornlists/ bns.par)
  6. ./simfactory/bin/sim setup-silent
    At this point you may have to edit ./simfactor/etc/defs.local.ini to enter the allocation name.
  7. ./simfactory/bin/sim build --thornlist
  8. ./simfactory/bin/sim create-submit bns --parfile bns.par --procs=128 --num-threads=4 --walltime=70:00:00
    Using this command it took approximately 33 hours to run on SuperMike.
  9. curl -LO
  10. python3 scripts/ bns
    Note that "bns" here is the sim name, and should match what you did in the submit-create step.
This thornlist contains the thorns of the Einstein Toolkit as well as the thorn NSTracker which is not part of the Einstein Toolkit yet.

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 36 hours using 128 cores
Results (90MB) bns-20230503.tar.gz

This example was last tested on 27-June-2024.

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