According to the present knowledge, the non-proportionality of the light yield of scintillators appears to be the fundamental limitation of energy resolution. However, several observations collected ...in the last 15 years on the influence of slow components of the light pulses on energy resolution suggest more complex processes in the scintillators. The presented study of undoped CsI crystals shows a large deterioration of the intrinsic resolution of the crystal, when most of the light, including slow component was integrated. Moreover, it was confirmed by a large difference of the non-proportionality characteristics measured at short peaking time, corresponding to the integration of the fast intrinsic emission of the CsI, and that observed with a long peaking time, when the slow component was integrated.
MCORD - MPD Cosmic Ray Detector a new features Bielewicz, M.; Milewicz-Zalewska, M.; Grodzicka-Kobylka, M. ...
EPJ Web of Conferences,
2019, Letnik:
204
Journal Article, Conference Proceeding
Recenzirano
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The main detector system at the Nuclotron-based Ion Collider fAcility (NICA) located in Dubna, Russia is the Multi-Purpose Detector (MPD). For better calibration reason, the MPD needs an additional ...trigger system for an off-beam calibration of MPD sub-detectors and for rejection (veto) of cosmic muons. The system should also be useful for practical astrophysics observations of cosmic showers. The consortium NICA-PL group defines goals and basic assumptions for the MPD Cosmic Ray Detector (MCORD). This article describes the conceptual design and simulation plans of the MCORD detector based on plastic scintillators with SiPM photodetectors and electronic digital system based on the MicroTCA crate.
MODES_SNM project aimed at developing a mobile/portable modular detection system for radioactive sources and Special Nuclear Material (SNM). Its main goal was to deliver a tested prototype capable of ...passively detecting weak or shielded radioactive sources with accuracy higher than that of currently available systems. By the end of the project all the objectives have been successfully achieved. Results from the laboratory commissioning and the field tests are presented in this publication.
Energy resolution of scintillation detectors Moszyński, M.; Syntfeld-Każuch, A.; Swiderski, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2016, Letnik:
805
Journal Article
Recenzirano
According to current knowledge, the non-proportionality of the light yield of scintillators appears to be a fundamental limitation of energy resolution. A good energy resolution is of great ...importance for most applications of scintillation detectors. Thus, its limitations are discussed below; which arise from the non-proportional response of scintillators to gamma rays and electrons, being of crucial importance to the intrinsic energy resolution of crystals. The important influence of Landau fluctuations and the scattering of secondary electrons (δ-rays) on intrinsic resolution is pointed out here. The study on undoped NaI and CsI at liquid nitrogen temperature with a light readout by avalanche photodiodes strongly suggests that the non-proportionality of many crystals is not their intrinsic property and may be improved by selective co-doping. Finally, several observations that have been collected in the last 15 years on the influence of the slow components of light pulses on energy resolution suggest that more complex processes are taking place in the scintillators. This was observed with CsI(Tl), CsI(Na), ZnSe(Te), and undoped NaI at liquid nitrogen temperature and, finally, for NaI(Tl) at temperatures reduced below 0°C. A common conclusion of these observations is that the highest energy resolution, and particularly intrinsic resolution measured with the scintillators, characterized by two or more components of the light pulse decay, is obtainable when the spectrometry equipment integrates the whole light of the components. In contrast, the slow components observed in many other crystals degrade the intrinsic resolution. In the limiting case, afterglow could also be considered as a very slow component that spoils the energy resolution. The aim of this work is to summarize all of the above observations by looking for their origin.
Nuclear spectroscopy experiments were performed for 100g metallic uranium rod enriched to 93% 235U, in order to establish and characterize the most prominent γ-rays in the natural decay series and ...photofission reaction. Single γ-ray spectra and γ–γ coincidences measurements were conducted before irradiation. The uranium sample was subsequently irradiated with 15MeV bremsstrahlung photons. Relative intensities of γ-lines and several values of half-lives of the fission fragments decays were determined. The obtained information can be utilized in detection of smuggled nuclear materials and characterization of bulky nuclear waste packages.
•The γ-lines in the natural decay series and photofission of highly enriched uranium were studied.•Single γ-ray spectra, γ–γ coincidences and photofission of uranium were investigated.•High-energy γ lines were identified as indicators of the presence of a uranium.•Enrichment of a U sample was roughly estimated.
In this paper results of gamma spectroscopy with the GAGG: 1%Ce scintillators with different Al-to-Ga ratio are showed. The study covered measurements of emission spectra, light output, energy ...resolution and non-proportionality for each crystal. It was observed that the light output of the recent set of scintillators was significantly improved in comparison to the previous set and varies from 40000 to 55000 ph/MeV. The best energy resolution of 3.7% at 662 keV was obtained using a Hamamatsu S8664-1010 avalanche photodiode. This result can be compared to scintillators possessing very good energy resolution, like LaCl 3 and CeBr 3 .
This article reports a detailed description of the integration tests of the first Rapidly Relocatable Tagged Neutron Inspection System (RRTNIS) carried out at the European Commission’s Joint Research ...Centre in Ispra (Italy). This technology allows the detection and identification of suspicious or illicit materials (such as narcotics, explosives, contraband goods, etc.) inside a cargo container using active neutron interrogation, with the so-called associated particle technique. The method is based on the measurement of the gamma photons emitted by the de-excitation of nuclei that undergo, mainly, inelastic scatterings with incident fast neutrons (En∼ 14 MeV). A set of scintillation detectors (NaI:Tl and LaBr3:Ce) is employed to perform gamma spectroscopy. The data acquisition system is based on fast signal digitizers and customized data acquisition software. A general technical description of the detection module and an outline of the data acquisition system (DAQ) are given. Also, we present the results of the integration tests, in particular, some examples of the performance of the system in the laboratory are shown, specifically, when using no target (background measurement) and when using mono-elemental and an explosive simulant target. Obtained results suggest that all technical requirements are achieved, and the next step will be the field trials.
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