Slobodan Jovanović

ANGLE: A PC-code for semiconductor detector efficiency calculations

AbstractA broadly applicable, flexible and user-friendly PC-code (ANGLE) for calculations of semiconductor detector full energy peak efficiencies (εp) is presented. The physical model behind is the concept of the effective solid angle

Patient dose measurements in diagnostic radiology procedures in Montenegro.

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Calibration of 4π NaI(Tl) detectors with coincidence summing correction using new numerical procedure and ANGLE4 software

. Written in Pascal, and operating in windows and menus data manipulation mode, ANGLE yields the efficiencies for: (1) HPGe true- and closed-end coaxial (bothn- andp-types), (2) Ge(Li) open- and closed-end, (3) planar LEPD and (4) well-type detectors. Supposing coaxial positioning, cylindrical or Marinelli sources can be treated, regardless of their dimensions (this includes point, disk and ring sources, bulky samples and infinite geometrics). Possible displacement between source and detector axes is treated in our another work, relative to this one. ANGLE input parameters are: (1) reference efficiency curve for the detector used (i.e., efficiency vs. γ-energy for calibrated point sources at a reference distance), (2) detector type and configuration (active body and inactive layers, end cap, windows, housing, shielding, (3) source data (dimension and composition of both container and active material), (4) source-detector geometry (distance, intercepting layers and their composition) and (5) some computational data (Gauss integration coefficients). Gamma-attenuation is calculated upon an extensive (per element and per energy) data file. In the output, efficiency vs. γ-energy is found, both in forms of tables and graphs. In routine applications accuracies of 3–4% are achieved (not worse than 7% for the most unfavourable geometries). Computation times when using recent PC models are of the order of minutes. ANGLE frame is also easily adjustable to other semiempirical or Monte Carlo models for efficiency calculations.

ANGLE v2.1—New version of the computer code for semiconductor detector gamma-efficiency calculations

AbstractWe known activities of two large cylindrical γ-sources (a mixture of radionuclides in solution, and a geological sample) are measured using a semiempirical method for calculating photon detection efficiencies (εp) of Ge-detectors via effective solid angles

Accounting for detector crystal edge rounding in gamma-efficiency calculations theoretical elaboration and application in ANGLE software

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A dose estimation for persons occupationally exposed to ionizing radiation in Montenegro

, in order to analyse the feasibility and the accuracy of the method. It is applied here under conditions not favourable to the method itself, which are however quite common in practice: (1) HPGe detector supplied only with standard detector specification and performance data, and (2) large source just above the detector end-cap. The impact of the probable range of uncertainties in knowledge of the detector and source geometrical parameters on the calculated efficiencies is considered. The fact that the crystal of the detector used is not coaxial with the end-cap, discovered by making X-ray radiographs, is of a special concern with respect to the applicability of the method under such conditions. Therefore, the method for the calculations of Ω is extended to cases of parallel but not coincident axes of the cylindrical sources and detectors. True coincidence effects, which introduce typically 5% errors for the counting geometry used, are not dealt with.