Understanding the smallest building blocks of the universe and their interactions by smashing heavy ions

Dynamic Modeling of Heavy-Ion Collisions

Detailed dynamical approaches that connect the properties of QCD matter such as the viscosity and the equation of state to final state observables are essential to gain quantitative insights. Triggered by detailed measurements, especially of correlation observables, and technical advances in high performance computing it has recently become possible to develop realistic event-by-event descriptions of the evolution of heavy ion collisions. These approaches need to contain the identified major ingredients on which a consensus has just emerged in the community, namely an early stage non-equilibrium evolution followed by a (nearly) ideal hydrodynamic expansion and subsequent gradual decoupling and hadronic rescatterings. The major goal is to develop a transport approach for the dynamical description of heavy ion reactions at FAIR using state-of-the-art scientific computing.

The transport model that is developed in this group is called SMASH. More information on the model, a publication list and a link to the source code on GitHub can be found on the SMASH webpage.


  • Institute for Theoretical Physics, Goethe University Frankfurt (ITP)
  • GSI Theory: Transport and Experiment Simulations
  • Center for Scientific Computing (CSC)
  • Model And Data Analysis Initiative (MADAI) collaboration
  • QCD group at Duke University
  • Alexander-von-Humboldt Stiftung (AvH)
  • Deutsche Telekom Stiftung


The ORCID profile of Hannah Elfner and the personal publication list on INSPIRE.

The Facility for Antiproton and Ion Research is under construction next to the campus of GSI in Darmstadt. It is the biggest German investment into an infrastructure for fundamental research. There are four main research pillars: APPA (atomic, plasma, material science and biophysics), NUSTAR (nuclear astrophysics and reactions), PANDA (hadron physics) and CBM (compressed baryonic matter). The main focus of this research group is on hot and dense nuclear matter. CBM at FAIR will be able to measure rare probes with high statistics due to the unprecedented luminosities that will be reached. From 2025, AuAu collisions up to beam energies of roughly 12 GeV per nucleon will be achieved. Conditions in density and temperature similar to the ones in neutron star mergers are reached in those collisions. Together with the theoretical interpretation, the goal is to find signatures of the first order phase transition implying the existence of a critical point in the QCD phase diagram.

Workshops and Conferences

  • INPC 2022, International Nuclear Physics Conference, September 11-16 2022, Cape Town, South Africa
  • CPOD 2021, International conference on Critical Point and Onset of Deconfinement, March 15-19 2021, Zoom, online
  • EMMI Workshop: Probing dense baryonic matter with hadrons: Status and Perspective, February 11-13 2019, GSI, Darmstadt, Germany
  • Quark Matter 2019, 28th International conference on ultrarelativistic nucleus-nucleus collisions, November 4-9 2019, Wuhan, China
  • NeD 2019, 7th International Symposium on Non-equilibrium Dynamics, June 16-22 2019, Castiglione della Pescaia, Italy
  • Hot Quarks 2018, September 7-14 2018, Texel, Netherlands
  • Quark Matter 2018, 27th International conference on ultrarelativistic nucleus-nucleus collisions, May 13-19, Venice, Italy
  • INT program Exploring the QCD Phase Diagram through Energy Scans, September 19-October 14 2016, Seattle, WA, USA
  • Hot Quarks 2016, September 12-17 2016, South Padre Island, Texas, USA
  • LHCP 2016, Fourth Annual Large Hadron Collider Physics Conference 2016, June 13-18 2016, Lund, Sweden
  • CIPANP 2015, Twelfth Conference on the Intersections of Particle and Nuclear Physics, May 19-24, 2015, Vail Colorado, USA
  • Riken-BNL Workshop: Theory and Modeling for the Beam Energy Scan: from Exploration to Discovery, February 26-27 2015, Brookhaven National Laboratory, NY, USA
  • Hot Quarks 2014, September 21-28 2014, Spain
  • FAIRNESS 2014, September 21-28 2014, Italy
  • Symposium on Non-equilibrium dynamics, June 8-14 2014, Crete, Greece
  • Quark Matter 2014, May 19-24 2014, Darmstadt, Germany
  • Transport and Sampling Workshop, July 15-20 2013, Taunus, Germany
  • FAIRNESS 2013, September 15-21 2013, Berlin, Germany
  • Hot Quarks 2012, October 14-20 2012, Copamarina, Puerto Rico
  • FAIRNESS 2012, September 3-8 2012, Hersonissos, Greece
  • Initial state fluctuations and final state correlations, July 2-6 2012, ECT*, Trento, Italy