Discrimination of neutrons and gamma-rays in plastic scintillator based on falling-edge percentage slope method

2021 ◽  
pp. 165483
Author(s):  
Zhuo Zuo ◽  
YuLong Xiao ◽  
ZhenFeng Liu ◽  
BingQi Liu ◽  
YuCheng Yan
Keyword(s):  
Gamma Rays ◽  
Plastic Scintillator ◽  
Slope Method

Gamma rays and high-energy neutrons in the atmosphere

1968 ◽  
Vol 46 (10) ◽  
pp. S1030-S1033 ◽  
Author(s):  
M. V. K. Apparao ◽  
R. R. Daniel ◽  
George Joseph ◽  
G. S. Gokhale ◽  
P. J. Lavakare ◽  
...  
Keyword(s):  
Gamma Rays ◽  
Counting Rate ◽  
Plastic Scintillator ◽  
Pulse Height ◽  
Growth Curves ◽  
High Energy ◽  
Cutoff Rigidity ◽  
Energy Formula ◽  
Γ Rays ◽  
Γ Ray

In continuation of our earlier experiments studying the emission of solar neutrons, we have now developed detector systems which respond to γ rays of energy 1–5 MeV and neutrons of energy [Formula: see text]. The two detectors are almost identical. Each consists of a CsI (Na) crystal (B) of diameter 3.8 cm, completely enclosed in a tapered cylinder of plastic scintillator (A) operated in anticoincidence; the crystals have thicknesses of 2.4 and 1.2 cm respectively. A balloon carrying these detectors was flown on March 16, 1967 over Hyderabad, India (vertical cutoff rigidity 16.9 GV) and floated at a ceiling altitude of 6.0 mb for 1 hour. In addition to γ-ray and neutron events (AB), events A and AB were also continuously monitored throughout the flight. Pulses corresponding to 1–5 MeV in the 2.4-cm crystal (γ rays) and 6–40 MeV in the 1.2-cm crystal (high-energy neutrons) were analyzed by a 64-channel pulse-height analyzer. On the basis of the pulse-height distributions and γ-ray efficiencies in the two crystals, we attribute events of 1–5 MeV energy from the thicker crystal to γ rays and those > 10 MeV in energy from the thinner one to stars produced by high-energy neutrons [Formula: see text] in the crystal. Atmospheric growth curves for γ rays and neutrons have been obtained; these growth curves as well as those for events A and AB show the normal features of the Pfotzer maximum, steady decreases up to the ceiling altitude, and a constant counting rate at ceiling. The atmospheric counting rates at ceiling altitude give for γ rays of energy 1–5 MeV a flux of ~1 photon per cm2 s and for neutrons of energy [Formula: see text] a flux of ~0.1 neutron per cm2 s. No evidence for a solar component in either channel was found.

scholarly journals Gas-Čerenkov Detector for 10 to 100 MeV Gamma Rays

1971 ◽  
Vol 41 ◽  
pp. 77-78 ◽  
Author(s):  
H. Helmken ◽  
J. Hoffman
Keyword(s):  
Gamma Radiation ◽  
Point Source ◽  
Gamma Rays ◽  
Angular Resolution ◽  
Galactic Plane ◽  
Plastic Scintillator ◽  
Spectral Information ◽  
Cerenkov Detector ◽  
Half Angle ◽  
Cerenkov Light

A gas-Čerenkov detector sensitive to gamma radiation above 10 MeV is currently undergoing final testing. The detector relies on the conversion and Compton scattering of gamma rays in a plastic scintillator and detecting the resulting electrons via the Čerenkov light they emit in a 2-m propane-gas column. Spectral information can be attained by varying gas pressure during the flight. The present detector is approximately 34″ in diameter, 91″ in length and weight 450 lb. At 20 MeV, an angular resolution of 6° half angle is expected. With an efficiency of 1 to 2%, a 10 hr balloon-borne system should achieve a point-source sensitivity of approximately 5× 10−5 photon cm−2 s−1 above 20 MeV. A satellite version of the detector is expected to have a sensitivity of approximately 1.3 × 10−5 photon cm−2 s−1 above 10 MeV for a 1-month galactic-plane scan mode. (Helmken and Hoffman, 1970.)

Gamma rays in the MeV region at balloon altitude

1968 ◽  
Vol 46 (10) ◽  
pp. S494-S497 ◽  
Author(s):  
K. Okudaira ◽  
Y. Hirasima
Keyword(s):  
Gamma Rays ◽  
Main Part ◽  
Counting Rate ◽  
Gamma Ray ◽  
Plastic Scintillator ◽  
Scintillation Counter ◽  
Lower Atmosphere ◽  
Upper Limit ◽  
Extraterrestrial Origin ◽  
The Difference

Gamma rays in the MeV region were observed from balloons at λ = 26 °N on September 29, 1966. A scintillation counter constructed with two NaI ⅓ in. × 2 in. [Formula: see text] crystals separated by 1 cm × 2 in. [Formula: see text] lead was used to measure the directional distribution of the gamma-ray flux. This counter was flown at an atmospheric depth of 14.2 g cm−2. As the response of each crystal of this counter depends on the direction of incidence of the gamma rays, an anisotropic distribution of gamma rays gives rise to a difference between the counting rates of two crystals. It was ascertained from the observation that albedo gamma rays from the lower atmosphere are predominant at this high altitude. The deviation from the calculated values of the difference in counting rate assuming only atmospheric gamma rays may be due to an extraterrestrial origin of part of the gamma-ray flux. For the measurement of the gamma-ray spectrum, a phoswich counter (1 in. × 1 in. [Formula: see text] NaI crystal surrounded by ¼-in.-thick plastic scintillator) was flown to 10 g cm−2. Though the main part of the gamma-ray flux is probably due to atmospheric gamma rays, an upper limit for the isotropic cosmic gamma-ray flux is deduced to be (1.25 ± 0.05) × 10−2 counts cm−2 s−1 sr−1 MeV−1 in the energy range 1.2–3.1 MeV.

Neutron-Gamma Discrimination Using Zero-Crossing Method for BC454 Boron Loaded Plastic Scintillator

2010 ◽  
Author(s):  
Dong Wang ◽  
Bin He ◽  
Quanhu Zhang
Keyword(s):  
Gamma Rays ◽  
Cross Sections ◽  
Plastic Scintillator ◽  
Detection Efficiency ◽  
Discrimination Performance ◽  
Slow Neutron ◽  
Fast Neutrons ◽  
Zero Crossing ◽  
High Detection Efficiency ◽  
Slow Neutrons

Boron loaded plastic scintillator could detect both fast neutrons (thanks to hydrogen) and slow neutrons (thanks to 10B). The large cross sections of both reactions lead to high detection efficiency of incident neutrons. However, gamma rays must be rejected first as the scintillator is also sensitive to them. In the present research zero crossing method was used to test neutron-gamma discrimination performance of BC454 boron loaded plastic scintillator. Three contrast experiments were carried out and different thermalization degrees lead to different time spectra in the MCA. Further analysis proved that three Gaussian curves could be used to fit the spectra; they corresponded to gamma rays, fast neutrons and slow neutrons respectively. The slow neutron curve could be clearly separated from the gamma curve. Discrimination performance for fast neutrons became poor, but their peaks could also be separated.

AN ANTICOINCIDENCE RING FOR A WHOLE-BODY COUNTER

1962 ◽  
Vol 40 (6) ◽  
pp. 732-738 ◽  
Author(s):  
K. G. McNeill ◽  
L. D. Davis
Keyword(s):  
Gamma Rays ◽  
Plastic Scintillator ◽  
Whole Body ◽  
Body Counter ◽  
Marked Diminution ◽  
Whole Body Counter

An account is given of an anticoincidence ring of plastic scintillator designed to fit round a 5 in. by 4 in. NaI crystal used as detector in a "whole-body counter". Results presented show that this system can produce a marked diminution of the background and that it can be usefully used to attenuate spectra of nuclides emitting gamma rays in cascade, thus helping in the analysis of complex spectra.

Discrimination of neutrons and gamma rays in plastic scintillator based on pulse-coupled neural network

2021 ◽  
Vol 32 (8) ◽  
Author(s):  
Hao-Ran Liu ◽  
Yu-Xin Cheng ◽  
Zhuo Zuo ◽  
Tian-Tian Sun ◽  
Kai-Min Wang
Keyword(s):  
Neural Network ◽  
Gamma Rays ◽  
Plastic Scintillator ◽  
Pulse Coupled Neural Network

scholarly journals Gamma-Ray Spectrometry in the Energy Range 0.5–5 MeV

1971 ◽  
Vol 41 ◽  
pp. 58-62 ◽  
Author(s):  
F. Albernhe ◽  
C. Doulade ◽  
I. M. Martin ◽  
R. Talon ◽  
G. Vedrenne
Keyword(s):  
Gamma Rays ◽  
Pulse Shape ◽  
Gamma Ray ◽  
Plastic Scintillator ◽  
Pulse Shape Discrimination ◽  
Field Of View ◽  
Gamma Ray Spectrometry ◽  
Shape Discrimination ◽  
Equatorial Latitude ◽  
Compton Electron

A stilbene scintillator detector allowing gamma-ray spectrometry in the range 0.5–5 MeV is presented. A complete elimination of charged particles is obtained by a plastic scintillator anticoïncidence jacket. Separation of gamma rays from neutrons is made by pulse shape discrimination technique with over 99% efficiency. This detector which has a 4 π field of view has been made as light as possible to avoid perturbation due to secondary production in the apparatus. The correction of the edge effects and the method of conversion from experimental Compton electron spectrum to gamma-ray spectrum are explained.Results from balloon launchings at three latitudes (Kourou Guyana: 10 N, Aire sur l'Adour: 46°N and Oboziersky U.S.S.R.: 62 °N) are briefly presented. The detection possibility with balloons of galactic gamma rays at equatorial latitude is shown. The atmospheric part of the flux at the equator is deduced from the measurements at higher latitudes, (46 °N and 62 °N) where the galactic component is of negligible importance. Assuming a power law spectrum and after correction of the atmospheric absorption we obtain for the galactic spectrum the expression dN/dE = 1.1 × 10−5E−1, 2 photons/cm2 s sr keV. This spectrum agrees with the results of ERS 18 satellite given by Vette et al. showing an excess of flux for energies higher than 1 MeV.

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