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Associated particle imaging instrumentation for future planetary surface missions
摘要： We have conducted ground tests to study the applicability of the Tagged Neutrons Method/Associated Particle Imaging methodology (TNM/API) for the making precise gamma ray spectroscopic measurements onboard lander missions to the Solar system planets. Our analysis was focused on the requirement to distinguish between the spacecraft background and the subsurface signal so as to correctly evaluate the elemental composition of planetary soils. The measurements were performed in a configuration where the gamma spectrometer was surrounded by significant amounts of material that imitated a spacecraft structure. It was found that the TNM/API can substantially suppress the spacecraft background and identify the true intensities of the gamma lines attributed to major soil elements such as O, Na, Mg, Al, Si and Fe and evaluate their concentrations with an accuracy of 2–10%.
关键词： Neutron generator,Elemental abundances,Surface operations,Associated particle imaging,Solar system,Tagged neutrons method,Active gamma spectroscopy
更新于2025-09-23 15:22:29
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Gamma spectral analysis by artificial neural network coupled with Monte Carlo simulations
摘要： Neutron activation analysis has been widely used for quantitative analysis. It can quantify elements in parts per million or billion. Artificial neural network is an attractive technique to analyze complex gamma spectra obtained from neutron activation. This study offers an improved methodology to analyze neutron activation gamma spectra using an artificial neural network. The methodology was demonstrated by quantifying five trace elements (Br, Na, Zn, K, Au) in common kidney stones. First, Monte Carlo simulations were used to create a large training data set. Then, an artificial neural network was employed for chemical elements identification analysis. For quantitative analysis, a Levenberg–Marquardt algorithm with 5 ? 23 ? 5 structure artificial neural network was used. The artificial neural network for analysis of simulated gamma spectra resulted in estimated element concentrations. The differences between true and estimated concentrations are 1.8% for Br, 3.4% for Na, 5.4% for Zn, 2.8% for K, and 1.6% for Au. For real gamma spectral analysis, the largest difference was found to be 28.2% for Zn in a calcium oxalate monohydrate type of kidney stones.
关键词： Kidney stone,Monte Carlo,Neural network,Gamma spectroscopy
更新于2025-09-12 10:27:22
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AIP Conference Proceedings [AIP Publishing LLC EXOTIC NUCLEI AND NUCLEAR/PARTICLE ASTROPHYSICS (V). FROM NUCLEI TO STARS: Carpathian Summer School of Physics 2014 - Sinaia, Romania (13–26 July 2014)] - Perspectives for neutron and gamma spectroscopy in high power laser driven experiments at ELI-NP
摘要： The measurement of energy spectra of neutrons and gamma rays emitted by nuclei, together with charge particles spectroscopy, are the main tools for understanding nuclear phenomena occurring also in high power laser driven experiments. However, the large number of particles emitted in a very short time, in particular the strong X-rays flash produced in laser-target interaction, impose adaptation of technique currently used in nuclear physics experiment at accelerator based facilities. These aspects are discussed (Section 1) in the context of proposed studies at high power laser system of ELI-NP. Preliminary results from two experiments performed at Titan (LLNL) and ELFIE (LULI) facilities using plastic scintillators for neutron detection (Section 2) and LaBr3(Ce) scintillators for gamma detection (Section 3) are presented demonstrating the capabilities and the limitations of the employed methods. Possible improvements of these spectroscopic methods and their proposed implementation at ELI-NP will be discussed as well in the last section.
关键词： gamma spectroscopy,neutron spectroscopy,nuclear physics,ELI-NP,high power laser
更新于2025-09-11 14:15:04
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Full-Energy Peak Efficiency Calibration of a Metallic Magnetic Calorimeter Detector for Photon Spectrometry Below 100?keV
摘要： Knowledge of absolute emission intensities of X-ray lines below 100 keV is limited or missing. An absolute determination of these intensities necessitates a high-resolution spectrometer with an accurate ef?ciency calibration. In this work, we will show and discuss the FEP ef?ciency calibration of a MMC detector combining a measurement of a standard source with Monte Carlo simulations using the code PENELOPE-2014. The simulated ef?ciency detection successfully interpolated the experimental ef?ciency values.
关键词： X-ray and gamma spectroscopy,Metallic magnetic calorimeter,FEP detection ef?ciency
更新于2025-09-10 09:29:36
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New Analytical Formulae to Calibrate Well-type Scintillation Detectors Efficiency
摘要： Direct Mathematical calculations for the absolute efficiency of well-type gamma ray scintillation crystals are described. Calculated detection efficiencies are drawn for two commonly used well crystals. Comparisons are made between present works and published Monte Carlo values. The present approach proved quite success in predicting the efficiency of well type detectors providing only the geometry and materials of the system formed of source, detector and shielding as well as the energy of the emitted photons.
关键词： Absolute efficiency,Well-type detector,Gamma-spectroscopy,New mathematical method
更新于2025-09-04 15:30:14