Observation of high-order electric multipoles in convoy electron angular distributions

The authors have discovered multipoles of even order up to about 10 in the multipole moments characterising angular distributions of convoy electrons ejected by swift ions during penetration of thin solids. It is suggested that the strongly transverse distributions observed reflect electron loss from excited n, l states inside the solid, which, though rapidly created and destroyed, progress toward finite dynamic equilibrium populations. Alternative interpretations are also discussed. (author)