  This study provides an accurate, efficient, and simple multiple scattering
formulation for heavy charged particles such as protons and heavier ions with a
new form of scattering power that is a key quantity for beam transport in
matter. The Highland formula for multiple scattering angle was modified to a
scattering-power formula to be used within the Fermi-Eyges theory in the
presence of heterogeneity. An analytical formula for RMS end-point displacement
in homogeneous matter was also derived for arbitrary ions. The formulation was
examined in terms of RMS angles and displacements in comparison with other
formulations and measurements. The results for protons, helium ions, and carbon
ions in water agreed with them at a level of 2% or the differences were
discussed.
