We have studied the prototype of a new plastic scintillator material (EJ-299-33) engineered for gamma-neutron discrimination. Energy and time resolutions as well as pulse shape discrimination ...capability have been compared with those of standard plastic and liquid scintillators. EJ-299-33 characteristics are somewhat poorer compared to standard scintillators. However, results obtained with the new plastic material suggest its possible use in basic research (time-of-flight measurements) as well as in Homeland Security applications (neutron/gamma monitoring device).
Pulse shape discrimination with fast digitizers Cester, D.; Lunardon, M.; Nebbia, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2014, Letnik:
748
Journal Article
Recenzirano
The pulse shape discrimination (PSD) between neutrons and gamma rays in liquid scintillators is studied by using the charge integration method with fast digitizers having different technical ...characteristics. The use of the Figure of Merit (FoM) to verify the PSD capability is discussed. The dependence of the FoM on the digitizer sampling rate and resolution is experimentally determined. The effects due to the type of source and the irradiation geometry are also evidenced and discussed.
Using a fast digitizer, the neutron–gamma discrimination capability of the new liquid scintillator EJ-309 is compared with that obtained using standard EJ-301. Moreover the capability of both the ...scintillation detectors to identify a weak neutron source in a high gamma-ray background is demonstrated. The probability of neutron detection is PD=95% at 95% confidence level for a gamma-ray background corresponding to a dose rate of 100μSv/h.
A short description of the muon tomography demonstrator at the INFN Laboratori Nazionali di Legnaro near Padua, Italy, is given and the principal achievements owing to the data collected at that ...experimental facility are presented. In particular, the feasibility studies for several applications based on the muon-tomographic technology, within national and European projects, are discussed. The experimental problems and the procedures used to improve the performance are underlined. In addition, new activities and the related detector optimization are illustrated.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.
In this work we present the characterization of a large area 200 mm ×200 mm EJ-444 scintillation detector to be used for monitoring gross alpha and beta activity in tap water plants. Specific tests ...were performed in order to determine the best setup to read-out the light from the detector side. The possibility to stack many detectors and get a compact device with total active area of the order of 1 m 2 has been explored. Alpha/beta discrimination, efficiency and homogeneity tests were carried out with alpha and beta sources. Background from ambient radioactivity was measured as well. Alpha/beta real-time monitoring in drinking water is a goal of the EU project TAWARA_RTM.
The light output response and the neutron and gamma-ray detection efficiency are determined for liquid scintillator EJ-309. The light output function is compared to those of previous studies. ...Experimental efficiency results are compared to predictions from GEANT4, MCNPX and PENELOPE Monte Carlo simulations. The differences associated with the use of different light output functions are discussed.
•New light output function for an EJ-309 detector and comparison with published data.•Experimental neutron and gamma ray detection efficiencies for an EJ-309 detector.•Comparison of measured efficiency with Monte Carlo calculations.•Role of the light output function in neutron efficiency calculations.
A commercial boron-loaded liquid scintillator EJ-339 A was studied, using a 252Cf source with/without polyethylene moderator, to examine the possibility of discriminating slow-neutron induced events ...in 10B from fast-neutron events, resulting from proton recoils, and gamma-ray events. Despite the strong light quenching associated with neutron induced events in 10B, correct classification of these events is shown to be possible with the aid of digital signal processing.
•Pulse shape neutron-gamma discrimination studies with an EJ-399A detector.•Study of neutron-induced events in 10B and the associated light quenching.•Study of “capture gated events” to characterize the signature of the thermal neutron events.•Identification of the thermal neutron events.•Study of effect of the shielding of a neutron source on the thermal/fast neutron ratio.
Special nuclear material detection with a mobile multi-detector system Cester, D.; Nebbia, G.; Stevanato, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2012, Letnik:
663, Številka:
1
Journal Article
Recenzirano
The detection of special nuclear material has been studied with a mobile inspection system used both as a high sensitivity passive neutron/gamma spectroscopic tool and as an active inspection device ...using tagged neutrons. The detection of plutonium samples seems to be possible with passive interrogation, even for small samples, thanks to the yield of gamma ray and neutrons. Moreover the gamma ray spectrum shows clear signatures related to
239Pu. The passive detection of uranium is much more difficult because of the low neutron yield and of the easiness of shielding the gamma ray yield of highly enriched U samples. However, we show that active interrogation with tagged neutrons is able to provide signatures for the discrimination of uranium against other heavy metals.
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