Objectif The main thrust of this project consists in performing systematic studies of dilepton production in heavy-ion collisions at bombarding energies between 1 to 10 AGeV with the HADES detector at FAIR. The highest baryonic densities are expected to be achieved close to the 10 AGeV and therefore it is of primary concern to extend HADES scope up to this energy. The goal being a better understanding of the various processes contributing to dilepton production in hot and compressed nuclear matter, leading ultimately to a search for signals of the partial restoration of the chiral symmetry of QCD, the theory of strong interactions.The chosen experimental approach consists in the measurement of lepton pairs from decaying baryon and meson resonances inside the reaction volume. The major experimental challenge thereby consists in discriminating the penetrating, but very weak leptonic signal from the many orders of magnitude larger hadronic background. The High-Acceptance Di-Electron Spectrometer HADES at GSI has in fact been designed with excellent lepton/hadron discrimination, a 10-fold better mass resolution (sM/M = 1-2%) and a nearly 100-fold higher acceptance (e = 32%) than the pioneering DLS spectrometer operated at the BEVALAC more than 10 years ago. Medium-resolution data have already been taken with HADES over the last years on the light C+C system at 1 and 2AGeV. Their detailed analysis gives first hints on the searched-for hadronic in-medium effects.A first physics run on the heavier system Ar+KCl was carried out in 2005 and the analysis of the data obtained is part of the project. An important next step of the present project is to complement HADES with the refurbished KaoS plastic forward wall, thus vastly enhancing its event-characterization capabilities. Finally, the extension of these experiments to heavy systems, beyond Ar+KCl and up to Au+Au, as well as to higher beam energies beyond the presently available 2AGeV, i.e. up to 10AGeV needs an upgrade of the HADES time-of-flight wall with a highly-segmented array of resistive-plate counters (RPC). Fully realistic simulation studies of HADES complemented by these new detector systems will be implemented, with the aim to verify the possibility to study with high mass resolution vector-meson production in Au+Au collisions up to a beam energy of 10AGeV. Mots‑clés Electromagnetic and Hadronic Probes Nuclear Instrumentation and Applications Nucleonic Structures Programme(s) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Thème(s) Data not available Appel à propositions Data not available Régime de financement Data not available Coordinateur NUCLEAR PHYSICS INSTITUTE (ASCR) Contribution de l’UE Aucune donnée Adresse ASCR-1 RE Tchéquie Voir sur la carte Coût total Aucune donnée Participants (4) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire GESELLSCHAFT FÜR SCHWERIONENFORSCHUNG (GSI) Allemagne Contribution de l’UE Aucune donnée Adresse PLANCKSTRASSE, 1 DARMSTADT Voir sur la carte Coût total Aucune donnée INSTITUTE OF NUCLEAR RESEARCH, RAS Russie Contribution de l’UE Aucune donnée Adresse 60TH OCTOBER ANNIVERSARY PROSPEKT, 7A MOSCOW Voir sur la carte Coût total Aucune donnée JOINT INSTITUTE FOR NUCLEAR RESEARCH (JINR) Russie Contribution de l’UE Aucune donnée Adresse JULIOT CURIE STREET, 6 DUBNA, MOSCOW REGION Voir sur la carte Coût total Aucune donnée UNIVERSIDADE DE COIMBRA Portugal Contribution de l’UE Aucune donnée Adresse COIMBRA Voir sur la carte Coût total Aucune donnée
