Meson and Di-Electron Production With Hades

Abstract

The HADES experiment, installed at GSI, Darmstadt, measures di-electron production in A + A, p/π + N and p/π + A collisions. Here, the π 0 and η Dalitz decays have been reconstructed in the exclusive p + p reaction at 2.2 GeV to form a reference cocktail for long-lived di-electron sources. In the C+C reaction at 1 and 2 GeV/u, these long-lived sources have been subtracted from the measured inclusive e + e − yield to exhibit the signal from the early phase of the collision. The results suggest that resonances play an important role in dense nuclear matter.