The Personal Radiation Detector (PRD) γ-Tracer GT2-1 was developed with a focus on gamma-radiation searches and detection and offers a gamma-radiation source localization function, enhanced PRD features and the capability of isotope energy pattern analysis. The device complies with general requirements and includes all typical features of PRD-class devices as well as supplementary modes such as multi-channel scaling (MCS), a spectrometer, library-driven analysis and a data logger. The GT2-1 uses a detector module built around a 0.4 cm³ counting-grade planar CdZnTe detector. CdZnTe offers high-efficiency gamma-radiation detection for a small detector volume and energy discrimination down to 30 keV. The GT2-1 was designed with power consumption in mind; its typical lifetime after a full battery charge exceeds 600 hours in measurements mode. Energy compensation techniques are employed for the dose rate calculations. The typical accuracy of the device in the energy range of 30–1500 keV is better than 10% for factory-calibrated devices. The GT2-1 features a library-driven isotope identification function. Its underlying concept is the use of a library of pre-calibrated user-defined isotope patterns for comparison with the isotope under investigation. The identification algorithm is designed to evaluate the isotope energy pattern match. The execution of the algorithm yields the matching results between the tested isotope and the library in graphical form. The device’s search mode employs a proprietary Background Variation Tracking (BVT) algorithm. The implemented search and gamma-radiation source localization mechanisms facilitate the rapid (1–3 sec) detection of weak gamma-radiation sources with intensities that exceed the background level by a factor of 1.5–3. Analysis of the time intervals between adjacent pulses in the input sequence is used to determine numeric characteristics that are also displayed in a user-friendly graphical form. The dedicated GUI approach and sound capabilities are tailored to facilitate search activities and support the operator in gaining experience with the device. The dedicated search algorithm implementation allows the device to be used as a homeland security detector by services responsible for the control of the relocation of radioactive materials, such as those at airports, border control checkpoints, and tolls. Test results for the GT2-1 in search mode are presented.

1. “Spectroscopic personal radiation detector identiFINDER R300,” FLIR Syst., Wilsonville (OR), USA, data sheets. Retrieved from: http://www.flir.com/ uploadedFiles/flirGS/Threat_Detection/Radiation_Detection/Products/IdenitiFINDER-300/DS_identiFINDER-R-300-en.pdf
2. “Spectrometric Personal Radiation Detector GalaxRay,” Galaxray, data sheets, 2016. Retrieved from: http://www.galaxray.com/products.html#tabs-tab-title-2.
3. V. Nagarkar, M. Squillante, G. Entine, I. Stern and D. Sharif, “CdTe Detectors in Nuclear Radiation Dosimetry,” Nucl. Instr. Meth. A, vol. 322, no. 3, pp. 623–627, Nov., 1992.
   DOI: 10.1016/0168-9002(92)91242-2
4. 4В.С. Горев, В.А. Кожемякин, О.А. Матвеев, М.Д. Фирсов, А. Х. Хуcaинoв, Г.К. Шульгович, “Примене-ние детекторов на основе теллурида кадмия в дозиметрии гамма-излучения,” Приборы и техника Эксперимента, №. 1, с. 60–64, 1981. (V.S. Gorev, V.A. Kozhemyakin, O.A. Matveev, M.D. Firsov, A.H. Husainov, G.K. Shul’govich, “Cadmium Telluride Based Detectors for Gamma Radiation Dosimetry,” Instruments and Technique of Experiment, no. 1, pp. 60-64, 1981.)
5. В.А. Мокрицкий, О.В. Маслов, О.В. Банзак, “Коррекция зависимости чувствительности CdZnTe-детектора от энергии гамма-излучения,” Збiрник наукових праць Вiйськового iнституту, Унiв. Тарас Шевченко, № 39, с. 81–84, 2013. (V.A. Mokrickii, O.V. Maslov, O.V. Banzak, “Correction of Gamma-Ray Energy Dependence Sensitivity of CDZnTe-Detector,” Monogr. Milit. Inst. Univ. Taras Shevchenko, no. 39, pp. 81-84, 2013.)
6. Rybka A.V. et al., “Gamma-Radiation Dosimetry with Semiconductor CdTe and CdZnTe Detectors,” NIM A, vol. 531, no. 1-2, pp. 147–156, Sep. 2004.
   DOI: 10.1016/j.nima.2004.05.107
7. R. Arlt et al., “Use of CdZnTe Detectors in Hand-Held and Portable Isotope Identifiers to Detect Illicit Trafficking of Nuclear Material and Radioactive Sources,” Nucl. Sci. Symp. Conf. Rec., IEEE 2000, vol.1, pp. 4/18–4/23.
   DOI: 10.1109/NSSMIC.2000.949040
8. Retrieved from: http://www.maths.qmul.ac.uk/~bb/TS_Chapter4_34.pdf