EMMI Hadron Physics Seminar

Baryon resonance excitation and dielectron decays in proton and pion induced reactions with HADES

by Prof. Piotr Salabura (Jagiellonian University)

Wednesday, April 6, 2016 from to (Europe/Berlin)
at GSI ( Theory Seminar Room (SB3 3.170a) )
Description
Studies of baryon resonance production and their em. decays have been conducted by HADES over last years. Primary motivation for this programme was to learn on vector meson-baryon couplings, which are predicted to play a dominant role for a modelling of in-medium spectral function of the rho meson and are the basis for successful description of low mass dilepton production in heavy ion collisions over a broad energy range. The elementary underlying process is so called dalitz decay to nucleon dielectron pair which is mediated by vector mesons as it is suggested by Vector Meson Dominance. For the first time, such decays have been measured in proton and pion beam experiments by HADES and have been analysed together with hadronic decays by means of Partial Wave Analysis provided by Bonn-Gatchina framework. In particular it will be argued that secondary pion beams combined with HADES is the word unique facility to investigate such transitions which are also of interest for baryon structure. Perspectives and plans for continuation of this programme in future with HADES will be presented too.