scholarly journals Nitrogen Detection in Bulk Samples Using a D-D Reaction-Based Portable Neutron Generator

2013 ◽  
Vol 2013 ◽  
pp. 1-7
Author(s):  
A. A. Naqvi ◽  
Faris A. Al-Matouq ◽  
F. Z. Khiari ◽  
M. A. Gondal ◽  
A. A. Isab ◽  
...  
Keyword(s):  
Excellent Agreement ◽  
Gamma Rays ◽  
Neutron Generator ◽  
Gamma Ray ◽  
Nitrogen Concentration ◽  
Prompt Gamma ◽  
Thermal Neutrons ◽  
Satisfactory Performance ◽  
Nitrogen Detection ◽  
Detector Material

Nitrogen concentration was measured via 2.52 MeV nitrogen gamma ray from melamine, caffeine, urea, and disperse orange bulk samples using a newly designed D-D portable neutron generator-based prompt gamma ray setup. Inspite of low flux of thermal neutrons produced by D-D reaction-based portable neutron generator and interference of 2.52 MeV gamma rays from nitrogen in bulk samples with 2.50 MeV gamma ray from bismuth in BGO detector material, an excellent agreement between the experimental and calculated yields of nitrogen gamma rays indicates satisfactory performance of the setup for detection of nitrogen in bulk samples.

scholarly journals Optical Afterglows as Probes for the Central Engine and Fireball of Gamma-Ray Bursts

2012 ◽  
Vol 8 (S290) ◽  
pp. 263-264
Author(s):  
Liang Li ◽  
En-Wei Liang ◽  
He Gao ◽  
Bing Zhang
Keyword(s):  
Statistical Analysis ◽  
Gamma Rays ◽  
Density Profile ◽  
Gamma Ray ◽  
Ambient Medium ◽  
Gamma Ray Bursts ◽  
Prompt Gamma ◽  
Medium Density ◽  
Central Engine ◽  
Prompt Emission

AbstractWell-sampled optical lightcurves of 146 gamma-ray bursts (GRBs) are compiled from literature. We identify possible emission components based on our empirical fits and present statistical analysis for these components. We find that the flares are related to prompt emission, suggesting that they could have the same origin in different episodes. The shallow decay segment is not correlated with prompt gamma-rays. It likely signals a long-lasting injected wind from GRB central engines. Early after onset peak is closely related with prompt emission. The ambient medium density profile is likely n ∝ r−1. No correlation between the late re-brightening bump and prompt gamma-rays or the onset bump is found. They may be from another jet component.

scholarly journals Improving the performance of 241Am-Be for PGNAA applications using a proper shielding for neutron source and the NaI detector

2010 ◽  
Vol 25 (3) ◽  
pp. 205-211 ◽  
Author(s):  
Hamed Panjeh ◽  
Hashem Hakimabad ◽  
Lalle Motavalli
Keyword(s):  
Gamma Rays ◽  
Energy Region ◽  
Gamma Ray ◽  
Region Of Interest ◽  
High Rate ◽  
Prompt Gamma ◽  
Peak Resolution ◽  
Set Up ◽  
Gamma Ray Detector

The gamma ray spectrum resolution from a 241Am-Be source-based prompt gamma ray activation analysis set-up has been observed to increase in the energy region of interest with enclosing the NaI detector in a proper neutron and gamma ray shield. We have investigated the tact that the peak resolution of prompt gamma rays in the region of interest from the set-up depends on the source activity to the great extent, size and kind of the detector and the geometry of the detector shield. In order to see the role of a detector shield, five kinds of the detector shield were used and finally the proper kind was introduced. Since the detector shield has an important contribution in the reduction of the undesirable and high rate gamma rays coming to the gamma ray detector, a good design of a proper shield enables the elimination of the unwanted events, such as a pulse pile-up. By improving the shielding design, discrete and distinguishable photoelectric peaks in the energy region of interest have been observed in the spectrum of prompt gamma rays.

scholarly journals INTERNAL ENERGY DISSIPATION OF GAMMA-RAY BURSTS OBSERVED WITHSWIFT: PRECURSORS, PROMPT GAMMA-RAYS, EXTENDED EMISSION, AND LATE X-RAY FLARES

2014 ◽  
Vol 789 (2) ◽  
pp. 145 ◽  
Author(s):  
You-Dong Hu ◽  
En-Wei Liang ◽  
Shao-Qiang Xi ◽  
Fang-Kun Peng ◽  
Rui-Jing Lu ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Internal Energy ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Gamma Ray Bursts ◽  
Prompt Gamma ◽  
X Ray ◽  
Extended Emission

Large solubility of lithium carboxylates reaching high rates of 6Li incorporation in polystyrene-based plastic scintillators for fast/thermal neutron and gamma ray detection

2019 ◽  
Vol 3 (8) ◽  
pp. 1626-1631 ◽  
Author(s):  
Camille Frangville ◽  
Matthieu Hamel ◽  
Guillaume H. V. Bertrand ◽  
Eva Montbarbon ◽  
Amélie Grabowski ◽  
...  
Keyword(s):  
Thermal Neutron ◽  
Homeland Security ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Thermal Neutrons ◽  
Plastic Scintillators

6Li-Doped plastic scintillators (PSs) have been optimized as radioluminescent sensors for detection of fast/thermal neutrons and gamma rays for several purposes such as homeland security.

ADRON instrument for future missions to Moon and Mars: active neutron and gamma-ray spectroscopy

2021 ◽  
Author(s):  
Maxim Mokrousov ◽  
Dmitriy Golovin ◽  
Igor Mitrofanov ◽  
Alexander Kozyrev ◽  
Maxim Litvak ◽  
...  
Keyword(s):  
Gamma Rays ◽  
Neutron Generator ◽  
Gamma Ray ◽  
Pulse Neutron ◽  
Good Time ◽  
Pulse Emission ◽  
Epithermal Neutrons ◽  
Mass Fractions ◽  
Detector Block ◽  
Gamma Ray Detector

<p>The series of ADRON instruments are developed in Russian Space Research Institute (IKI) for Russian Luna-25, Luna-27 and Roscosmos-ESA ExoMars-2022 landers. The main goal of this experiment is studying of elemental composition of planetary sub-surface down to 1 m. Using pulsing neutron generator and observing albedo after-pulse neutron and gamma-ray emission from the soil, one can detect layering stratification of hydrogen and mass fractions of other elements.</p><p>Both instruments consist of two blocks: pulsing neutron generator (PNG) with 14 MeV neutron pulse duration around 1 microsecond, and detector block with neutrons and gamma-ray detectors based on <sup>3</sup>He counters and CeBr<sub>3</sub> (LaBr3) scintillator, respectively. <sup>3</sup>He counters allow to detect thermal and epithermal neutrons, which are the most sensitive to hydrogen in underlying soil, and gamma-ray detector allows to detect nuclear lines at the energy range from 200 keV up to 10 MeV. Readout and digital electronics is designed to minimize the dead-time of signal processing. It allows to accumulate the after-pulse profiles of emission of neutrons and gamma-rays with very good time (from 2 microsecond) and spectral resolutions (about 4 % for 662 keV).</p><p>The results of laboratory measurements and numerical simulations for ADRON units will be presented for post-pulse emission of neutrons and gamma rays from the planetary soil with different water content, elementary composition and layering structure.</p><p> </p>

scholarly journals Prompt Fission Gamma-Ray Measurements at UML Research Reactor

2020 ◽  
Vol 242 ◽  
pp. 01009
Author(s):  
Razvan Stanescu ◽  
Hadrick Green ◽  
Toby Morris ◽  
Gencho Rusev ◽  
Marian Jandel
Keyword(s):  
Gamma Rays ◽  
Research Reactor ◽  
Gamma Ray ◽  
Fission Neutron ◽  
Pulse Shape Discrimination ◽  
Prompt Gamma ◽  
Fission Reaction ◽  
Induced Fission ◽  
Enriched Uranium ◽  
Prompt Fission

Neutron-induced fission of 235U was studied at the thermal column of the UMass Lowell 1 MW Research Reactor. A collimated, 2.25-inch diameter beam of thermal neutrons with the flux of ~5x105 n/cm2/sec induced fission reaction on a plate of low-enriched uranium with the areal density ~25 mg/cm2 of 235U. We have used the prompt fission-neutron tagging method to identify the fission reaction in the off-line analysis. The method employs the pulse-shape discrimination of neutrons and gamma-ray events in stilbene scintillator and enables identification of coincidence events of prompt fission gamma-rays and prompt fission neutrons in coincidence time intervals less than 20-30 ns. The prompt gamma-ray radiation was detected using two co-linear NaI(Tl) detectors. The measured spectra of prompt-fission gamma rays between 150 keV and 6 MeV are presented. The results from these initial measurements demonstrate the feasibility of the experimental method. Future measurements with extended arrays of detectors are planned.

Performance Evaluation of a Portable Neutron Generator for Prompt Gamma-Ray Applications

2013 ◽  
Vol 39 (1) ◽  
pp. 531-539 ◽  
Author(s):  
A. A. Naqvi ◽  
Zameer Kalakada ◽  
M. S. Al-Anezi ◽  
Faris Al-Matouq ◽  
M. Maslehuddin ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Neutron Generator ◽  
Gamma Ray ◽  
Prompt Gamma

scholarly journals Multiple Gamma-Ray Detection Capability of a CeBr3 Detector for Gamma Spectroscopy

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
A. A. Naqvi ◽  
F. Z. Khiari ◽  
F. A. Liadi ◽  
Khateeb ur-Rehman ◽  
M. Raashid ◽  
...  
Keyword(s):  
Energy Range ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Gamma Spectroscopy ◽  
Prompt Gamma ◽  
Detection Capability ◽  
Gamma Energy ◽  
Best Value ◽  
Detection Capabilities ◽  
Good Agreement

The newly developed cerium tribromide (CeBr3) detector has reduced intrinsic gamma-ray activity with gamma energy restricted to 1400–2200 keV energy range. This narrower region of background gamma rays allows the CeBr3 detector to detect more than one gamma ray to analyze the gamma-ray spectrum. Use of multiple gamma-ray intensities in elemental analysis instead of a single one improves the accuracy of the estimated results. Multigamma-ray detection capability of a cylindrical 75 mm × 75 mm (diameter × height) CeBr3 detector has been tested by analyzing the chlorine concentration in water samples using eight chlorine prompt gamma rays over 517 to 8578 keV energies utilizing a D-D portable neutron generator-based PGNAA setup and measuring the corresponding minimum detection limit (MDC) of chlorine. The measured MDC of chlorine for gamma rays with 517–8578 keV energies varies from 0.07 ± 0.02 wt% to 0.80 ± 0.24. The best value of MDC was measured to be 0.07 ± 0.02 wt% for 788 keV gamma rays. The experimental results are in good agreement with Monte Carlo calculations. The study has shown excellent detection capabilities of the CeBr3 detector for eight prompt gamma rays over 517–8578 keV energy range without significant background interference.

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