luminescent response of phosphors and scintillators to ions with energies in the 0-100 kev range
abstract
a survey of the ionoluminescence of a large number of ion-phosphor
combinations under uniform conditions has been made.
powdered phosphors and scintillation crystals with different
activators, different methods of surface treatment and different
particle size were studied in the energy range from 3—100 kev.
l, the ratio of integrated photomultiplier output to incident ion
current, was found to be a sensitive function of ion energy. it
increased with increasing ion energy and decreased with increasing
ion mass. a nonlinear relationship between l and e, the ion energy,
was observed for heavier ions, the nonlinearity increasing with ion
mass. comparisons of l values obtained in zns, yv04 and in zn2si04:mn
phosphors of different particle size and with different activators
were made. the results indicated that the light output may depend on
the mechanism of luminescence, the crystal structure and the activaactivators,
as well as the surface conditions of the samples. by taking
into consideration the non-radiative surface recombination of electron
hole pairs and assuming that the rate of generation of carrier pairs
along the path of a particle is proportional to the specific energy
loss in electron collision (de/dr)e, a formula was obtained to predict
the nonlinear dependence of l at low energies.
collections
- retrospective theses [1604]