  A method for calibrating the momentum scale in a particle physics detector is
described. The method relies on the determination of the masses of the final
state particles in two-body decays of neutral particles, which can then be used
to obtain corrections in the momentum scale. A modified version of the
Armenteros-Podolanski plot and the $K_S^0 \to \pi^+ \pi^-$ decay is used as a
proof of principle for this method.
