@article{PoudelTichyBruegmannetal.2020,
  author    = {Poudel, Amit and Tichy, Wolfgang and Br{\"u}gmann, Bernd and Dietrich, Tim},
  title     = {Increasing the accuracy of binary neutron star simulations with an improved vacuum treatment},
  series = {Physical review : D, Particles, fields, gravitation, and cosmology},
  volume    = {102},
  journal   = {Physical review : D, Particles, fields, gravitation, and cosmology},
  number    = {10},
  publisher = {American Physical Society},
  address   = {College Park},
  issn      = {2470-0010},
  doi       = {10.1103/PhysRevD.102.104014},
  pages     = {16},
  year      = {2020},
  abstract  = {Numerical-relativity simulations are essential for studying the last stages of the binary neutron star coalescence. Unfortunately, for stable simulations there is the need to add an artificial low-density atmosphere. Here we discuss a new framework in which we can effectively set the density surrounding the neutron stars to zero to ensure a more accurate simulation. We test our method with a number of single star test cases and for an equal-mass binary neutron star simulation. While the bulk motion of the system is not influenced, and hence there is no improvement with respect to the emitted gravitational-wave signal, we find that the new approach is superior with respect to mass conservation and it allows a much better tracking of outward moving material. This will allow a more accurate simulation of the ejected material and supports the interpretation of present and future multimessenger observations with more accurate numerical-relativity simulations.},
  language  = {en}
}