Scintillation Characteristics of Americium 241 Doped Thallium Activated Sodium Iodide

The scintillation response of NaI(Tl) crystals to an alpha emitter, americium 241, grown into the crystal lattice was investigated. Americium 241 was added to the NaI salt prior to meltdown and growth. As a result it was dispersed throughout the ingot volume. Several ingots were grown. Test data obtained from these crystals are presented. These data include alpha peak resolution, the gamma equivalent energy of the alpha peak, and the variation of relative pulse height and gamma equivalent energy with temperature from -50 degrees C to 150 degrees C. Also reported are the specific activity levels attained.