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Obtaining directional information is required in many applications such as nuclear homeland security, contamination mapping after a nuclear incident and radiological events, or during the decontamination work. However, many directional radiation detectors are based on directional shielding, made of lead or tungsten collimators, introducing two main drawbacks. The first is the size and weight, making those detectors too heavy and irrelevant for utilization in handheld devices, drone mapping, or space applications. The second drawback is the limited field of view, which requires multiple detectors to cover the whole required field of view or machinery to rotate the narrow field of view detector. We propose a novel 4π directional detector based on a segmented hollow cubic detector, which uses the Compton effect interactions with no heavy collimators. The symmetrical cubical design provides both higher efficiency and 4π detection ability. Instead of traditional two types of detectors (scatterer and absorber) structure, we use the same type of detector, based on GAGG(Ce) scintillator coupled to silicon photomultiplier. Additional advantage of the proposed detector obtained by locating the photon sensors inside the detector, behind the scintillators, which improves the radiation hardness required for space applications. Furthermore, such arrangement flattens the temperature variation across the detector, providing better gain stability. The main advantage of the proposed detector is the ability of 4pi radiation detection for high energy gamma-rays without the use of heavy collimators. [ABSTRACT FROM AUTHOR]

In this paper we propose a method of fast neutron flux estimation from a pulsed D-T neutron generator with application of single CaF2 scintillation crystal. The analysis method relies on 19F(n, α)16N threshold activation reaction having neutron energy threshold at 1.6 MeV. As a result, the 16N undergo β− decay with half-life of 7.1 s, emitting β particles with endpoint up to 10.4 MeV in the scintillator medium. Integration of the β distribution curve, preceded by calculation of (n, α) rate on F with Monte Carlo N-Particle Transport Code v6 (MCNP6) for fixed geometry, allows to estimate the neutron flux in 4π per second within few minutes. [ABSTRACT FROM AUTHOR]

The helium-3 world crisis requires a development of new methods of neutron detection to replace commonly used 3He proportional counters. In the past decades, great effort was made to developed efficient and fast scintillators to detect radiation. The inorganic scintillator may be an alternative. Inorganic scintillators with much higher density should be selected for optimal neutron detection efficiency taking into consideration the relevant reactions leading to light emission. These detectors should, then, be carefully characterized both experimentally and by means of advanced simulation code. Ideally, the detector should have the capability to separate neutron and gamma induced events either by amplitude or through pulse shape differences. As neutron sources also generate gamma radiation, which can interfere with the measurement, it is necessary that the detector be able to discriminate the presence of such radiation. Considerable progress has been achieved to develop new inorganic scintillators, in particular increasing the light output and decreasing the decay time by optimized doping. Crystals may be found to suit neutron detection. In this report, we will present the results of the study of lead doped cesium iodide crystals (CsI:Pb) grown in our laboratory, using the vertical Bridgman technique. The concentration of the lead doping element (Pb) was studied in the range 5x10-4 M to 10-2 M . The crystals grown were subjected to annealing (heat treatment). In this procedure, vacuum of 10-6 mbar and continuous temperature of 350°C, for 24 hours, were employed. In response to neutron radiation, an AmBe source with energy range of 1 MeV to 12 MeV was used. The activity of the AmBe source was 1Ci Am. The fluency was 2.6 x 106 neutrons/second. The operating voltage of the photomultiplier tube was 1700 V; the accumulation time in the counting process was 600 s and 1800 s. The scintillator crystals used were cut with dimensions of 20 mm diameter and 10 mm height. [ABSTRACT FROM AUTHOR]

The helium-3 world crisis requires a development of new methods of neutron detection to replace commonly used 3He proportional counters. In the past decades, great effort was made to developed efficient and fast scintillators to detect radiation. The inorganic scintillator may be an alternative. Inorganic scintillators with much higher density should be selected for optimal neutron detection efficiency taking into consideration the relevant reactions leading to light emission. These detectors should, then, be carefully characterized both experimentally and by means of advanced simulation code. Ideally, the detector should have the capability to separate neutron and gamma induced events either by amplitude or through pulse shape differences. As neutron sources also generate gamma radiation, which can interfere with the measurement, it is necessary that the detector be able to discriminate the presence of such radiation. Considerable progress has been achieved to develop new inorganic scintillators, in particular increasing the light output and decreasing the decay time by optimized doping. Crystals may be found to suit neutron detection. In this report, we will present the results of the study of lead doped cesium iodide crystals (CsI:Pb) grown in our laboratory, using the vertical Bridgman technique. The concentration of the lead doping element (Pb) was studied in the range 5х10-4 M to 10-2 M . The crystals grown were subjected to annealing (heat treatment). In this procedure, vacuum of 10-6 mbar and continuous temperature of 350°C, for 24 hours, were employed. In response to neutron radiation, an AmBe source with energy range of 1 MeV to 12 MeV was used. The activity of the AmBe source was 1Ci Am. The fluency was 2.6 х 106 neutrons/second. The operating voltage of the photomultiplier tube was 1700 V; the accumulation time in the counting process was 600 s and 1800 s. The scintillator crystals used were cut with dimensions of 20 mm diameter and 10 mm height. [ABSTRACT FROM AUTHOR]

This paper summarizes a Photomultiplier-Scintillator diagnostic system for use in our plasma focus experiments at the Center for Plasma Research INTI IU. The system features an anode-grounded high pulse linearity voltage divider and uses NE102A plastic scintillators. It has detected D-D neutrons in INTI plasma focus device with clear and high signal to noise ratio. Neutron TOF of 120 ns has been measured from the time difference between hard x-ray pulse peak and neutron peak time over a flight path of 2.6±0.01 m; giving energy of 2.5±0.1 MeV for these side-on neutrons. [ABSTRACT FROM AUTHOR]

The main goal of this project was the improvement of the energy resolution of the scintillating detectors. In order to obtain the required energy resolution at the level of ~8%, which corresponds to the half-life sensitivity of about 1.2 × 1026 years for the SuperNEMO experiment [1], an optimal ratio of concentrations of the activator (pTP) and the wavelength shifter (POPOP) in the purified polystyrene (PS) base had to be found. Furthermore, good optical properties and mainly the energy resolution for such improved detectors are comparable with properties for higher price plastic scintillators based on the polyvinyltoluene (PVT). In this contribution, the results of the measurement with the organic plastic scintillators with various composition are presented. [ABSTRACT FROM AUTHOR]

The main goal of this project was the improvement of the energy resolution of the scintillating detectors. In order to obtain the required energy resolution at the level of ~8 %, which corresponds to the half-life sensitivity of about 1.2 ×1026 years for the SuperNEMO experiment [1], an optimal ratio of concentrations of the activator (pTP) and the wavelength shifter (POPOP) in the purified polystyrene (PS) base had to be found. Furthermore, good optical properties and mainly the energy resolution for such improved detectors are comparable with properties for higher price plastic scintillators based on the polyvinyltoluene (PVT). In this contribution, the results of the measurement with the organic plastic scintillators with various composition are presented. [ABSTRACT FROM AUTHOR]

BrilLanCe 380™ (LaBr3:Ce) crystal scintillators available from Saint-Gobain Crystals have achieved 2.6% FWHM for 662 keV photons. This is accomplished with PMT light sensors. Attempts to have similarly good results with PIN photo-diodes and APDs have not been successful. PIN photodiodes do not have any gain and the signal to noise ratio is poor at room temperature. Similarly, even though APDs have sufficient gain, they have poor signal to noise at room temperature. Recently there have been improvements in APDs decreasing the internal noise and increasing their sensitivity, making them an excellent light sensor. With the improved APD, it is now possible to achieve performance with a solid state light sensor comparable to that of PMTs. We have measured 2.8% for 662 keV gamma rays at room temperature using an APD for a light sensor on a 20 mm long crystal of 1.6 cc volume. APDs have advantages of compactness, inherent ruggedness and minimal sensitivity to magnetic fields. Such a device is very practical for hand held and portable field measurement applications. (Performance reported in SGC literature.) [ABSTRACT FROM AUTHOR]

In this presentation we describe the testing of a new cerium doped Lanthanum Chloride crystal (LaCl3:Ce), which makes an excellent scintillation material for X-ray counting applications. Detailed measurements were taken to determine the properties of the scintillator over an energy range of 5 to 60KeV; the results demonstrate that, when used with an appropriate PMT, the crystal sustains high count rates, minimal dead time and good energy resolution. For example an energy resolution of 35% (FWHM) was achieved at 22KeV and count rates of up to 1MHz are possible without dead-time correction. A comparison of LaCl3:Ce with two conventional scintillation materials, YAP:Ce and NaI(Tl) is also presented, which shows that that LaCl3:Ce offers a good balance of performance parameters for X-ray experiments. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A highly-granular, 38-layer, analog scintillator-tile hadron calorimeter prototype is under construction by members of the Calice collaboration in order to study hadronic shower shapes and to test the calorimetric aspects of particle-flow. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The active modules of the CALICE scintillator HCAL (or AHCAL for analog hadronic calorimeter) prototype are being commissioned using cosmic muons and the DESY electron test beam. These first data allow to check the functionality of the photo-detectors, the readout chain and the calibration electronics; and to test the performance of the entire system. This proceeding will discuss first operational experience, calibration and correction procedures, data analysis and results. The status of preparations for the first hadron beam measurements to start in summer 2006, and the data taking plans are also presented. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The V0A detector is one of the forward detectors that will be used for trigger in the ALICE experiment at CERN. Simulation results of the optical response of the V0A elements are presented in this work. The simulations are based on the LITRANI package. The simulation results guarantee a flat response of the whole detector as well as within each cell of the array. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The present work demonstrates the application of the digital technique for nuclear measurements. This method has been implemented for measurements of promptly emitted fission neutrons in coincidence with fission fragments from 252Cf(sf). A double Frisch-grid ionization chamber is used as fission fragment detector. The promptly emitted neutrons are detected by a NE213 liquid scintillation detector. The experimental set-up is installed at the Institute for Reference Materials and Measurements. Preliminary results are presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The dark matter search project PICO-LON has been started. Thin and wide area NaI(Tl) scintillator is the promising detector system to study the properties of dark matter particle. [ABSTRACT FROM AUTHOR]

Scintillators are materials which emit light when energetic particles deposit energy in their volume. It is a quasi-universal requirement that the light detected in scintillator setups be maximised. The following project aims to study how the light collection is affected by surface depolishing using the simulation programs GEANT4 [1] and LITRANI [2]. [ABSTRACT FROM AUTHOR]