RAP Probes


The CsI (Tl) crystal used in Radiation Alert® Probes has a higher atomic number, is more rugged, and less hygroscopic than a typical Nal detector. The improved gamma ray absorption allows a thinner crystal to be used, effectively reducing the background count rate.

  • Thin-crystal (1 mm) optimizes sensitivity to low energy gamma radiation while minimizing sensitivity to higher energies.  An excellent detector for Iodine-125 and suitable for thyroid uptake measurements.
  • A 0.25-inch crystal optimizes this for the detection of special nuclear material (SNM) such as U-235, or related isotopes  such as Am-241, much like a mini-FIDLER.
  • Superior to a 1 x 1-inch NaI detector, this is a great choice for an all-around gamma and x-ray detector. Optimal energy  range of about 20 keV to 2 MeV. Highest efficiency for a broad spectrum of gamma-emitting isotopes.