Due to energy losses in the interstellar medium, cosmic ray electrons at TeV energies carry
information on local (within a few hundred parsecs) accelerators. However, measurements
of the spectrum of the cosmic ray electrons beyond 1 TeV are extremely difficult due to the
rapidly declining flux and the much more numerous background of nucleonic cosmic rays. The
very large collection area of Cherenkov telescope arrays makes them promising instruments
with which to measure these high energy electrons. While Cherenkov telescopes solve the
problem of low fluxes of cosmic ray electrons in the TeV range, they still have to deal with
the problem of distinguishing them from the nucleonic background. Here we report on
first results towards a measurement of the cosmic ray electron spectrum with the High
Energy Stereoscopic System (H.E.S.S.). The improved background supression that is needed
for such a measurement is achieved by an event classification with the 'Random Forest'
algorithm based on decision trees.

H.E.S.S. collaboration

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 2 (OG part 1), pages 35-38