Electron identification and hadron contamination studies in proton-proton collisions with ALICE

The continuum of electron-positron pairs, produced in heavy ion collisions, provides an excellent probe of quark-gluon plasma formation in nucleus-nucleus collisions. Dielectrons are also studied in proton-proton collisions to provide a crucial reference. To extract possible signatures, it is important to work with an electron sample of high purity. This can be achieved optimizing the electron identification and reducing the hadron contamination. In this proceeding, the analysis of a dataset of pp collisions at √ s = 7 TeV measured with the ALICE detector at the Large Hadron Collider is described. The invariant mass spectra of electron-positron pairs based on three different PID sets are compared and the hadron contamination of the dielectron sample is estimated as a function of invariant mass. The analysis shows that one can achieve good electron identification efficiencies and a single electron purity higher than 90% by combining the signals of the ITS, TPC and TOF detectors in ALICE.