Interference effects in Auger resonant Raman spectra of CO via selective vibrational excitations across the O 1s-->2pi resonance

The Auger resonant Raman spectra of CO, arising from the transitions to the X and A final electronic states of CO+, have been recorded at photon energies corresponding to the vibrational excitations v[prime]=3,5, and 8 in the O 1s-->2pi resonance. The spectra are simulated within the model that takes into account both the lifetime-vibrational interference (LVI) and interference with the nonresonant photoemission. The spectroscopic parameters, omegae, omegaexe, Gamma and re, of the O 1s–12pi core-excited state, necessary for the simulation, have been derived by fitting the Franck-Condon simulation to the total ion yield spectrum, assuming a Morse potential for the O 1s–12pi state. Not only the LVI but also the interference with the nonresonant photoemission turn out to be significant

Low energy lepton scattering: Recent results for electron and positron interactions

This report will review several new experimental developments for low energy (1-50 eV) scattering of both electrons and positrons from atoms and molecules. Experiments include an apparatus for studies of scattering from unstable molecular radicals, a position- and time-sensitive time-of-flight spectrometer for studies of near threshold electronic excitation of atoms and molecules and a trap-based positron scattering experiment for measurements of low energy positron scattering from rare gas atoms. Where possible, comparisons are also made with other experimental determinations and with contemporary scattering theory