  A method is proposed for detecting positron-atom bound states by observing
enhanced positron annihilation due to electronic Feshbach resonances at
electron-volt energies. The method is applicable to a range of open-shell
transition metal atoms which are likely to bind the positron: Fe, Co, Ni, Tc,
Ru, Rh, Sn, Sb, Ta, W, Os, Ir, and Pt. Estimates of their binding energies are
provided.
