Zahlavi

Research Overview

Department of Heavy Ion Physics was established in 2024. It covers the research we carry out through our participation in experiments at major international laboratories, where we study the properties of nuclear matter under extreme conditions, relativistic and ultra-relativistic heavy ion collisions, neutrino mass measurements, and the weak interaction in beta decay.

Collaboration with prestigious foreign laboratories (CERN, BNL, GSI) that investigate properties of nuclear matter under extreme conditions is one of the pillars of the research done at the department. The Ultra-Relativistic Heavy Ion Group focuses primarily on the study of quark-gluon plasma (QGP). This exotic nuclear-matter phase exhibits behavior similar to that of perfect liquid. It can be created in a laboratory in collisions of heavy nuclei at ultra-relativistic energies, which are accessible only at the world's largest accelerators - LHC (Large Hadron Collider) in the European laboratory CERN and RHIC (Relativistic Heavy Ion Collider) at Brookhaven National Laboratory (BNL) in the U.S.A. The ALICE experiment at CERN and the STAR experiment at BNL, in which we have participated since the beginning, study nuclear collisions in the energy domain of tens of GeV to TeV. This research is related for example to models of the early evolution of the Universe after the Big Bang and the search for the critical point of the phase diagram of nuclear matter.

Research activities of the Relativistic Heavy Ion Group are devoted to the investigation of nuclear collisions in the energy domain of a few GeV per nucleon-nucleon collision available at GSI Darmstadt (Germany) and focus on exploration of properties of hadrons in nuclear matter at high baryon density. In particular, for many years the group has been involved in the large international experiment HADES at the SIS18 accelerator. In parallel, the group members are preparing the new experiment CBM at the FAIR facility at GSI which will allow us to explore nuclear matter at high baryon density with unprecedented precision. Exploration of the phase diagram of nuclear matter in this domain further extends the measurements carried out at RHIC and can be linked to models of neutron stars or our understanding of supernova explosions. Furthermore, we are participating in the preparation of the future experiment ePIC, which aims to explore cold nuclear matter in collisions of electrons with heavy nuclei at the EIC facility.

An inherent part of research carried out within large international experiments is the research in the Electron Spectroscopy Group. This group belongs to founding members of the international experiment KATRIN (KIT Karlsruhe, Germany) designed to measure neutrino mass with a sensitivity of 0.2 eV, ten times better than so far experimentally achieved. This unique experimental device became operational in 2018. The Czech team from the NPI is primarily responsible for the development of an ultra-stable method to control the energy scale stability of the KATRIN spectrometer together with the development of a gaseous 83mKr generator.

Members of the department are also traditionally involved in international experiments located at the radioactive-ion-beam facility ISOLDE at CERN. Currently, we are participating in a new project VITO that makes use of laser-polarized isotope beams and the WISARD experiment, a successor of the project WITCH that searches for a possible presence of scalar current in weak interaction in electron-neutrino correlations.