Dielectron Production in C+C Collisions at 1 GeV/u and the Solution to the DLS Puzzle

TL;DR

This paper reports on dielectron production in C+C collisions at 1 GeV/u, revealing an excess in the invariant-mass spectrum that helps resolve the longstanding DLS puzzle in heavy-ion collision experiments.

Contribution

The study provides new experimental data from HADES that confirms previous DLS results and offers insights into dielectron production mechanisms at this energy.

Findings

Observed a significant dielectron excess above hadron decay contributions.

Data aligns with previous DLS experiment results.

Supports the solution to the DLS puzzle.

Abstract

The production of e+e- pairs in C+C collisions at 1 GeV/u was investigated with the HADES experiment at GSI, Darmstadt. In the invariant-mass region $ 0.15\: GeV/c^{2} \leq M_{ee} \leq 0.5\: GeV/c^{2}$ the measured pair yield shows a strong excess above the contribution expected from hadron decays after freeze-out. The data are in good agreement with the results of the former DLS experiment for the same system and energy.