Frankfurt 2014 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HK: Fachverband Physik der Hadronen und Kerne

HK 5: Schwerionenkollisionen und QCD Phasen

HK 5.7: Talk

Monday, March 17, 2014, 15:30–15:45, HZ 7

Lepton identification performance in Au+Au at 1.23 GeV/u in HADES — •Szymon Harabasz for the HADES collaboration — TU Darmstadt

The High Acceptance Di-Electron Spectrometer, installed at GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, has measured rare penetrating probes and strange particles production in elementary as well as in heavy ion collisions. The heaviest system, Au+Au at a maximum available at SIS18 beam kinetic energy of 1.23 GeV/u has been measured by HADES in April - May 2012. In such collisions, extracting a sample of very rare di-electrons radiated from a dense fireball plays a crucial role. Therefore, a pure electron identification is necessary. This is achieved by exploring information from the Ring Imaging Cherenkov detector in combination with the time-of- flight measurement and with an evidence of an electromagnetic shower formation. A sequence of one- or two-dimensional cuts does not meet requirements. Therefore lepton identification has to be done using a multi-dimensional condition calculated by an artificial neural network. In this contribution I will present results on efficiency and purity of electron identification obtained using multi-variate analysis method.

Supported by: ViP-QM/VH-NG-823, BMBF (05P12RFGHJ), Helmholtz Alliance EMMI, HIC for FAIR, HGS-HIRe.