CsI(Tl) film scintillators 20-25 mg/cm2 thick with areas of approximat
ely 150 cm2 prepared by vacuum deposition were investigated. The scint
illators have a light yield close to that of a CsI(Tl) single crystal.
The amplitude resolution was measured for 83 specimens under alpha-ir
radiation from a collimated ThC' alpha-source and ranged from 12 to 20
% in the main. When the entire scintillator is mounted on a conical li
ght guide and irradiated by alpha-particles, the resolution is approxi
mately half as much because the light transmittance of the light guide
depends on the flash position. The half-intensity thickness for the s
cintillator's intrinsic emission is 16-20 mg/cm2. The depth of the sur
face dead layer is no more than 1 mg/cm2. The light yield for differen
t detected particles with different energies (He-4, Li-6, and N-14 wit
h maximum energies of 60, 80, and 70 MeV, respectively) was studied. T
he results are consistent with the data reported for single-crystal sc
intillators.