Study of Electron Identification in the OPERA Detector

The OPERA experiment is designed to perform first direct observation of $\nu_{\tau}$ appearance in an almost pure $\nu_{\mu}$ beam. The OPERA detector is a hybrid setup which combines a lead/emulsion target with various electronic detectors. It is located in Gran Sasso Laboratory (LNGS), 730 km away from CERN where neutrino beam is produced. A good electron identification in the ECC brick would also allow OPERA to search for $\nu_{\mu} \to \nu_e$ oscillations. We have studied electron identification in the Emulsion Cloud Chamber (ECC) brick which was exposed to CERN SPS H4 electron beam. Emulsion scanning was performed in LNGS scanning laboratory. FEDRA framework was used for the data analysis. In total, we have found 30 electron showers in the brick. The characteristics of each shower have been studied. The background base-track contamination in the shower was estimated as 20 $\pm$ 4. This is mainly due to shower overlap of electrons and passing through cosmic rays.