Binary Neutron Stars Merger Simulations (2015)

Overview

The theory that describes gravitational interactions in astrophysics and cosmology is General Relativity. The gravitational field is interpreted geometrically and matter interacts dynamically with space-time. The accurate theoretical study of extreme astrophysical objects (such as pulsar, x-rays sources, neutron stars, black holes, etc.) requires the use of Einstein's equation coupled to equations for both, matter and the electromagnetic fields.

Here you can find companion material to the publication: "Modeling Equal and Unequal Mass Binary Neutron Star Mergers Using Public Codes" Phys. Rev. D 93, 064047 (arXiv:1509.08804) by De Pietri, Feo, Maione and Loeffler. The investigation has been done using only publicly available open source software, in particular, the Einstein Toolkit code deployed for the dynamical evolution and the LORENE code for the generation of the initial models. All of the source code and parameters used for the simulations have been made publicly available. This not only makes possible to re-run and re-analyze our data; it also enables others to directly build upon this work for future research.

The modified code as well as the post processing (Python) scripts can be download from the SVN server:
svn --username=anonymous checkout https://einstein.pr.infn.it/svn/numrel/pub/ #(passwd: anon)

We kindly ask to cite (arXiv:1509.08804) if you find any of the material here useful for your own research.

Instructions

In order to checkout the source code necessary to re-run our simulations, use the GetComponents script:

  ./GetComponents https:/einstein.pr.infn.it/gravity/Research/BNS2015.th
  

Compiling the Einstein Toolkit is outside of the scope of this document, but the following tutorial might help: Einstein Toolkit New Users Tutorial.

Here you can find a 3D visulization of two Neutron Stars merging and than collapsing to a Black Hole

Evolution of an equal mass model





Evolution of an un-equal mass model






Black Hole formation