HADES experiment: Di-lepton spectroscopy in p+p (2.2 GeV) and C+C (1 and 2 A GeV) collisions

The HADES (High Acceptance Di-Electron Spectrometer) is a tool designed for lepton pair (e+e-) spectroscopy in pion, proton and heavy ion induced reactions in the 1-2 A GeV energy range. One of the goals of the HADES experiment is to study in-medium modifications of hadron properties like effective masses, decay widths, electromagnetic form factors etc. Such effects can be probed with vector mesons (ρ, ω, Φ) decaying into e +e- channel. The identification of vector mesons by means of a HADES spectrometer is based on invariant mass reconstruction of e +e- pairs. The combined information from all spectrometer sub-detectors is used to reconstruct the di-lepton signal. The recent results from 2.2 GeV p + p, 1 A GeV and 2 A GeV C+C experiments are presented.