Journal or Book Title
Physical Review Letters
Thermoreflectance measurements on LiF and KCl were made from 10 to 30 eV using synchrotron radiation. Analysis of the differential dielectric and electron-energy-loss functions shows that the energy-loss peak generally attributed to the valence plasmon actually arises from the plasmon and overlapping longitudinal-exciton-like peak(s).
The American Physical Society
Piacentini, M.; Olson, C. G.; and Lynch, David W., "Thermomodulation Study of Plasmons and Longitudinal Excitons in Alkali Halides" (1975). Physics and Astronomy Publications. 38.