  Cosmic Ray and neutrino oscillation physics can be studied by using
atmospheric neutrinos. JUNO (Jiangmen Underground Neutrino Observatory) is a
large liquid scintillator detector with low energy detection threshold and
excellent energy resolution. The detector performances allow the atmospheric
neutrino oscillation measurements. In this work, a discrimination algorithm for
different reaction channels of neutrino-nucleon interactions in the JUNO liquid
scintillator, in the GeV/sub-GeV energy region, is presented. The atmospheric
neutrino flux is taken as reference, considering $\overset{(-)}{\nu_\mu}$ and
$\overset{(-)}{\nu_e}$. The different temporal behaviour of the classes of
events have been exploited to build a time profile-based discrimination
algorithm. The results show a good selection power for $\overset{(-)}{\nu_e}$
CC events, while the $\overset{(-)}{\nu_\mu}$ CC component suffers of an
important contamination from NC events at low energy, which is under study.
Preliminary results are presented.
