ASTROPHYSICS

Astrophysics

Principal Investigator: Sebastiano Bernuzzi, Bernd Brügmann , Friedrich-Schiller-Universität Jena

HPC Platform used: SuperMUC and SuperMUC-NG of LRZ

Local Project ID: pn56zo

The project developed multiscale 3+1D simulations of binary neutron mergers in numerical general relativity for applications to multi-messenger astrophysics. It focused on two aspects: (i) the production of high-quality gravitational waveforms suitable for template design and data analysis, and (ii) the investigation of merger remnants and ejecta with sophisticated microphysics, magnetic-fields induced turbulent viscosity and neutrino transport schemes for the interpretation of kilonova signals. The simulations led to several breakthroughs in the first-principles modeling of gravitational-wave and electromagnetic signal, with direct application to LIGO-Virgo's GW170817 and counterparts observations. All data products are publicly released.

Astrophysics

Principal Investigator: David Hilditch and Bernd Brügmann , Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität Jena (Germany)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr87nu

General relativity describes the gravitational interaction as the curvature of spacetime. This involves complicated partial differential equations, and consequently extreme scenarios can be treated only by numerical simulations. In this project spacetimes close to the critical threshold of black hole formation were evolved on SuperMuc. These computations were performed using bamps, a new massively parallel code for numerical relativity. The spacetimes constructed constitute the most extreme regime imaginable - that in which cosmic censorship itself may be violated and the black hole singularity could be seen by distant observers. 

Astrophysics

Principal Investigator: (1)Bernd Brügmann, (2)Tim Dietrich , (1)Friedrich-Schiller-University, Jena, (2)Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Potsdam-Golm (Germany)

HPC Platform used: SuperMUC of LRZ

Local Project ID: pr48pu

The recent observations of gravitational waves (GWs) marked a breakthrough and inaugurated the field of GW astronomy. To extract information from a detection, the measured signal needs to be cross-correlated with a template family. However, due to the nonlinearity of Einstein’s equations, numerical simulations have to be used to study systems with gravitational fields strong enough to emit GWs. This project focused on the simulation of systems consisting of two neutron stars and investigated the effect of the mass ratio and the influence of the spin of the individual stars.