  Beam stripping losses of H- ion beams by interactions with residual gas and
electromagnetic fields are evaluated. These processes play an important role in
compact cyclotrons with internal ion source and high magnetic fields. The
implementation of residual stripping interactions into the beam dynamics code
OPAL provides an adequate framework to estimate the stripping losses for
compact cyclotrons such as AMIT. The analysis is focused on optimizing the
final beam current of the cyclotron, adjusting parameters of the ion source to
regulate the vacuum level inside the accelerator, minimizing the beam stripping
losses.
