An internal consistency test of the calculation of coincidence-summing correction factors FC for volume sources is presented. The test is based on exact equations relating the values of FC calculated ...for three ideal measurement configurations. The test is applied to a number of 33 sets of FC values sent by 21 teams. Most sets passed the test, but not the results obtained using the quasi-point source approximation; in the latter case the test qualitatively indicated the magnitude of the bias of FC.
•A self-consistency test of coincidence summing calculations is presented.•It is based on equations relating FC values for 3 ideal volume geometries.•Can be easily applied in any laboratory for checking the quality of FC software.•33 sets of FC values (various computations) for 60Co, 133Ba, 134Cs, 152Eu evaluated.•Inconsistency and bias of FC based on quasi-point source approximation revealed.
In this paper the suitability of two non-destructive analytical techniques for identification of elemental signatures in samples containing uranium of different enrichments was studied. The ...measurements were based on particle induced X-ray emission (PIXE) and particle induced gamma-ray emission (PIGE) methods. The samples were irradiated by 3 and 5 MeV protons at the 3 MV Tandetron™ of Horia Hulubei National Institute for Physics and Nuclear Engineering. The characteristic X and gamma rays were measured using high purity germanium (HPGe) detectors. The GUPIX software was applied for processing the PIXE spectra, while a relative standardization was applied for PIGE analysis by using certified comparator standards and proton stopping powers calculated by SRIM.
The aim of this study was to check for equivalence of computer codes that are capable of performing calculations of true coincidence summing (TCS) correction factors. All calculations were performed ...for a set of well-defined detector parameters, sample parameters and decay scheme data. The studied geometry was a point source of 133Ba positioned directly on the detector window of a low-energy (n-type) detector. Good agreement was established between the TCS correction factors computed by the different codes.
•Equivalence of computer codes used for calculation of TCS corrections was checked.•Codes were compared with each other for a well-defined detector and sample model.•All the codes used the same DDEP decay scheme data.•A simulated 133Ba point source was placed onto the window of an n-type detector.•Good agreement was found between the results of the different computer codes.
The antenna array LOPES is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and aims to measure and investigate radio pulses from extensive air ...showers. The coincident measurements allow us to reconstruct the electric field strength at observation level in dependence of general EAS parameters. In the present work, the lateral distribution of the radio signal in air showers is studied in detail. It is found that the lateral distributions of the electric field strengths in individual EAS can be described by an exponential function. For about 20% of the events a flattening towards the shower axis is observed, preferentially for showers with large inclination angle. The estimated scale parameters
R
0
, describing the slope of the lateral profiles range between 100 and 200
m. No evidence for a direct correlation of
R
0
with shower parameters like azimuth angle, geomagnetic angle, or primary energy can be found. This indicates that the lateral profile is an intrinsic property of the radio emission during the shower development which makes the radio detection technique suitable for large scale applications.
Five different numerical algorithms used for calculating coincidence summing corrections (CSCs) in HPGe γ-spectrometry in case of complex radionuclide decay schemes were tested for their equivalence. ...Simulated point-source detection geometries and efficiency curves have been used to calculate and compare counting rates as well as CSCs of
133Ba,
134Cs and
152Eu of 1
MBq sources. Contributions of one X-ray per radionuclide were included. The algorithms were found to give identical results within their respective presuppositions.
The aim of the study was to check for equivalence of computer codes that can perform calculations of true coincidence summing correction factors. All calculations were performed for a set of ...well-defined detector and sample parameters, without any reference to empirical data. For a p-type detector model the application of different codes resulted in satisfactory agreement in the calculated correction factors. For high-efficiency geometries in combination with an n-type detector and a radionuclide emitting abundant X-rays the results were scattered.
•Measured and calculated true coincidence corrections differ in recent study.•We checked for equivalence of computer codes that can perform such calculations.•Codes compared with each other for a set of well-defined detector and sample models.•Satisfactory agreement between the codes for a p-type detector model.•Large differences for an n-type detector model and X-ray emitting radionuclides.
A new method for the calculation of coincidence summing out corrections appropriate for γ-spectrometry measurements in the Ge well-type detector geometry is proposed. The method is based on a simple ...formula for the total efficiency of the detector, using an exact analytical relation for the mean detector thickness, combined with approximate formulas describing the interactions in the source and in the materials interposed between the source and the detector. The method can be easily applied for establishing the corrected, nuclide independent, efficiency calibration curves of Ge well-type detectors using experimental calibration data obtained with the common mixed γ-ray standard source containing
60Co and
88Y.
Four general Monte Carlo codes (GEANT3, PENELOPE, MCNP and EGS4) and five dedicated packages for efficiency determination in gamma-ray spectrometry (ANGLE, DETEFF, GESPECOR, ETNA and EFFTRAN) were ...checked for equivalence by applying them to the calculation of efficiency transfer (ET) factors for a set of well-defined sample parameters, detector parameters and energies typically encountered in environmental radioactivity measurements. The differences between the results of the different codes never exceeded a few percent and were lower than 2% in the majority of cases.
Using data measured by the KASCADE-Grande air shower array, an upper limit to the flux of ultra-high energy gamma-rays in the primary cosmic-ray flux is determined. KASCADE-Grande measures the ...electromagnetic and muonic components for individual air showers in the energy range from 10 PeV up to 1 EeV. The analysis is performed by selecting air showers with low muon contents. A preliminary result on the 90% C.L. upper limit to the relative intensity of gamma-ray with respect to cosmic ray primaries is presented and compared with limits reported by other measurements.
In this paper we present a new semi-empirical model calculation of the peak efficiency for unshielded HPGe detectors based on the virtual point detector and the attenuation factor concepts. The ...validity of the model calculation was checked by comparison with Monte Carlo efficiency values and experimental efficiencies determined for a HPGe detector type GEM 25P4 using a calibration drum. The discrepancy between experimental and calculated efficiencies is smaller than 10% in the energy range 122–1408
keV.
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