Electrons emitted from 33-TeV Pb ions during penetration of solids

Electrons ejected in the forward direction from fully-stripped and one-elec tron 33-TeV Ph ions passing through thin foils of Al and Au have been studi ed. Spectral peaks centered at a momentum equivalent to the velocity of the projectile have been measured, which are attributed toelectron loss to the projectile continuum(ELC). From previous theoretical studies, the ELC 'cus p' shape is expected to reflect the initial state of the electron released from the projectile. The ELC peaks are very narrow even for loss from groun d-state incident ions. The observed widths arise primarily from instrumenta l broadening effects - especially multiple Coulomb scattering (MCS). Correc tion of the measured electron momentum distributions for instrumental broad ening leads to very narrow ELC cusps, which have essentially the same width s for loss from incident one-electron ground-state ions and loss from hydro genic ions populated by electron capture from pair production (ECPP), where there should be significant excited-state formation.