  We report on our study of photon emission induced by Enu ~ 1 GeV
(anti)neutrino neutral current interactions with nucleons and nuclei. This
process is an important background for nu_e appearance oscillation experiments.
At the relevant energies, the reaction is dominated by the excitation of the
Delta (1232) resonance but there are also non-resonant contributions that,
close to threshold, are fully determined by the effective chiral Lagrangian of
strong interactions. We have obtained differential and integrated cross section
for the (anti)neutrino-nucleon scattering and compare them with previous
results. Furthermore, we have extended the model to nuclear targets taking into
account Fermi motion, Pauli blocking and the in-medium modifications of the
Delta properties. This study is important in order to reduce systematic effects
in neutrino oscillation experiments.
