Bibliografias temáticas / Photon spectrometry

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Literatura científica selecionada sobre o tema "Photon spectrometry"

Autor: Grafiati

Publicado: 14 de dezembro de 2024

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Artigos de revistas sobre o assunto "Photon spectrometry"

Behrens, Rolf, Hayo Zutz e Julian Busse. "Spectrometry of pulsed photon radiation". Journal of Radiological Protection 42, n.º 1 (17 de janeiro de 2022): 011507. http://dx.doi.org/10.1088/1361-6498/ac3dd0.

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Abstract The energy distribution (spectrum) of pulsed photon radiation can hardly be measured using active devices, therefore, a thermoluminescence detector (TLD)-based few-channel spectrometer is used in combination with a Bayesian data analysis to help resolve this problem. The spectrometer consists of 30 TLD layers interspaced by absorbers made of plastics and metals with increasing atomic numbers and thickness. Thus, the main idea behind the device is the deeper the radiation penetrates—the higher the radiation’s energy when the radiation impinges perpendicular to the front of the spectrometer. From the doses measured in the TLD layers and from further prior available information, the photon spectrum is deduced using a Bayesian data analysis leading to absolute spectra and doses including their uncertainties and coverage intervals. This spectrometer was successfully used in two different scenarios, i.e. for the spectrometry of the radiation field two different industrial type open beam pulsed x-ray generators and secondly in three different radiation fields of a medical accelerator.

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Lockyer, Nicholas P., e John C. Vickerman. "Single Photon Ionisation Mass Spectrometry Using Laser-Generated Vacuum Ultraviolet Photons". Laser Chemistry 17, n.º 3 (1 de janeiro de 1997): 139–59. http://dx.doi.org/10.1155/1997/53174.

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This paper provides an overview of the method of single photon ionisation mass spectrometry. A review of the theory of frequency upconversion using third-order 4- wave sum mixing in isotropic media and experimental results of third harmonic generation (THG) using a frequency tripled 355 nm Nd:YAG pump source are presented. Vacuum Ultra-violet (VUV) photons of wavelength 118 nm are detected in an acetone ionisation chamber. The emphasis of this paper is on the practical aspects of generating and detecting the VUV photons and using them for single photon ionisation (SPI) in the ion source of a mass spectrometer. Optimum gas pressures for THG in Xe and Xe/Ar mixtures are established. For a pump beam of well defined mode structure the optimum gas pressures are in excellent agreement with theory. The major loss mechanism is attributed to re-absorption of VUV by the tripling gas. SPI mass spectra of hexane and the biomolecule valyl-valine are presented illustrating the power of the technique.

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Fairbank, W. M. "Photon burst mass spectrometry". Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 29, n.º 1-2 (novembro de 1987): 407–14. http://dx.doi.org/10.1016/0168-583x(87)90274-6.

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Besnard-Vauterin, C., V. Blideanu e B. Rapp. "Development of a new method for the detection of illicit materials based on the Active Photon Interrogation Method and photo-neutron spectrometry". EPJ Web of Conferences 288 (2023): 06004. http://dx.doi.org/10.1051/epjconf/202328806004.

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The detection of illicit materials is a critical task in the field of homeland security, as international trade has contributed to the increase of smuggling activities. Nonintrusive on-site inspections are crucial in this context, but the current active interrogation methods have limitations. Neutron-induced reactions have been used, but the measurement of gamma spectra is complex due to background noise. Active photon interrogation methods have also been overlooked but they are currently limited to actinides detection using photo-fission reactions. This work presents a novel method for the detection of illicit materials based on active photon interrogation and photo-neutron spectrometry. This approach extends the application of active photon interrogation by including the detection of conventional explosives, narcotics, and chemical weapons based on the use photo-nuclear reactions to determine the content of light elements such as nitrogen, oxygen, and carbon. Monte-Carlo codes are the main tool used to simulate this process for the application need. However, because of the lack in the present literature of measured neutron spectra, the experimental validation of the simulations is not straight forward. At present, benchmarking the Monte-Carlo codes seems to be the sole option for testing their ability to accurately simulate photo-neutron production and spectra for the nuclear reactions of interest. Simultaneously, we designed a test bench based on a linear accelerator to generate photons, induce photonuclear reactions, and acquire photo-neutron spectra. This study on the fundamental aspects of photo-neutron production lays the groundwork for a promising new detection method for illicit materials.

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Klein, H. "Photon spectrometry in mixed fields". Radiation Protection Dosimetry 107, n.º 1-3 (1 de novembro de 2003): 125–31. http://dx.doi.org/10.1093/oxfordjournals.rpd.a006381.

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Omori, Yasutaka, Atsuyuki Sorimachi, Masahiro Hosoda, Sarata Kumar Sahoo, Norbert Kavasi, Osamu Kurihara, Shinji Tokonami e Tetsuo Ishikawa. "Improvement of spectral analysis using a NaI(Tl) scintillation spectrometer to evaluate ambient gamma dose rates from primordial radionuclides". Radiation Protection Dosimetry 199, n.º 18 (novembro de 2023): 2233–37. http://dx.doi.org/10.1093/rpd/ncad258.

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Abstract In-situ measurements by gamma-ray spectrometry using a NaI(Tl) scintillation spectrometer are performed to discriminate primordial and artificial radionuclides contributing to ambient gamma dose rates in the living environment to quantify prolonged influence of nuclear accidents. However, low energy resolution of the spectrometer causes poor discrimination in the measurements at high-dose-rate points, which leads to overestimation of ambient gamma dose rate from the primordial radionuclides. The present study clarified that photon fluxes originating from 40K and 214Bi were affected by the presence of 134Cs, whereas those from 208Tl were independent of it. In addition, the absorbed dose rates in air were strongly correlated with the 208Tl photon fluxes. These findings indicate that 208Tl photon fluxes can be used to evaluate absorbed dose rates in air from the primordial radionuclides. When estimated from the 208Tl photon fluxes only, the absorbed dose rates in air in Namie Town and Okuma Town, locations affected by the Fukushima Dai-ichi Nuclear Power Plant accident, were 19–71 and 20–47 nGy h−1, respectively.

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Šolc, J., P. Dryák, J. Rusňák, V. Sochor e Z. Vykydal. "Practical X-ray beam spectrometry with cadmium telluride detector in 10–300 kVp range at Czech Metrology Institute. Part II. Unfolding". Journal of Instrumentation 17, n.º 10 (1 de outubro de 2022): P10003. http://dx.doi.org/10.1088/1748-0221/17/10/p10003.

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Abstract The paper summarizes computational methods and software tools used at Czech Metrology Institute for unfolding of X-ray photon fluence spectra from detector spectra measured with a cadmium telluride (CdTe) spectrometer directly in the X-ray beam. Fluence spectra were determined using multi-channel unfolding software GRAVEL. Response functions were calculated by Monte Carlo (MC) method using the general-purpose code MCNP® in version 6.2 with EPRDATA14 photon cross-section tables. The detailed MC model of the CdTe spectrometer was developed and it was validated by comparison with full-energy peak detection efficiencies measured with selected radionuclide sources. The adopted methods and tools enable to fulfil requirements of the ISO 4037 standard dealing with the necessity of direct measurement of X-ray beam photon fluence spectra whose parameters do not comply with the ones listed in the standard. The instrumentation part for the X-ray beam spectrometry at CMI is described in a separate paper [1].

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Lamprou, Theocharis, Rodrigo Lopez-Martens, Stefan Haessler, Ioannis Liontos, Subhendu Kahaly, Javier Rivera-Dean, Philipp Stammer et al. "Quantum-Optical Spectrometry in Relativistic Laser–Plasma Interactions Using the High-Harmonic Generation Process: A Proposal". Photonics 8, n.º 6 (29 de maio de 2021): 192. http://dx.doi.org/10.3390/photonics8060192.

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Quantum-optical spectrometry is a recently developed shot-to-shot photon correlation-based method, namely using a quantum spectrometer (QS), that has been used to reveal the quantum optical nature of intense laser–matter interactions and connect the research domains of quantum optics (QO) and strong laser-field physics (SLFP). The method provides the probability of absorbing photons from a driving laser field towards the generation of a strong laser–field interaction product, such as high-order harmonics. In this case, the harmonic spectrum is reflected in the photon number distribution of the infrared (IR) driving field after its interaction with the high harmonic generation medium. The method was implemented in non-relativistic interactions using high harmonics produced by the interaction of strong laser pulses with atoms and semiconductors. Very recently, it was used for the generation of non-classical light states in intense laser–atom interaction, building the basis for studies of quantum electrodynamics in strong laser-field physics and the development of a new class of non-classical light sources for applications in quantum technology. Here, after a brief introduction of the QS method, we will discuss how the QS can be applied in relativistic laser–plasma interactions and become the driving factor for initiating investigations on relativistic quantum electrodynamics.

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Kudo, K., N. Takeda, S. Koshikawa, H. Toyokawa, H. Ohgaki e M. Matzke. "Photon spectrometry in thermal neutron standard field". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 476, n.º 1-2 (janeiro de 2002): 213–17. http://dx.doi.org/10.1016/s0168-9002(01)01434-6.

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Aleksandrov, D., J. Alme, V. Basmanov, B. Batyunya, D. Blau, M. Bogolyubsky, V. Budilov et al. "Solving a Deconvolution Problem in Photon Spectrometry". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 620, n.º 2-3 (agosto de 2010): 526–33. http://dx.doi.org/10.1016/j.nima.2010.03.148.

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Teses / dissertações sobre o assunto "Photon spectrometry"

Finch, Jeffrey William. "Selective mass spectrometry by single-photon ionization from a molecular hydrogen laser source". Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185895.

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A molecular hydrogen laser, with an output of 7.8 eV photons in the vacuum ultraviolet, is evaluated as a selective source for photoionization mass spectrometry. Types of compounds ionized by the laser include a variety of amines, nitrogen heterocycles, drugs of abuse, pharmaceuticals, and polynuclear aromatic hydrocarbons (PAHS). The laser is coupled to a time-of-flight mass analyzer, which allows a spectrum to be recorded with each laser pulse. The laser is a "soft" ionization source and mass spectra of nearly all of the compounds studied yield single ion peaks due to the parent molecule with no fragments. This results in simplified mass spectra with a one-to-one correspondence of photoactive molecules with molecular ion peaks. Since the photoionization threshold of the laser is relatively low, selectivity of the photoactive species is high in the presence of a complex sample matrix. The performance of the laser source is improved with a few changes in the original design. In addition, the previous method of recording mass spectra with a photographic emulsion is replaced with a digital oscilloscope, which averages spectra over many laser pulses. As a result, a true assessment of the technique's sensitivity is finally achieved. The time-of-flight mass spectrometer is modified with a new microchannel plate ion detector and preamplifier. As a result, detection limits for PAH's improve by nearly three orders of magnitude, from the 100 ng range to the 100 pg range. Selectivity of the laser photoionization source in complex mixture analysis is demonstrated with the ability to detect PAH's in a drinking water sample at concentrations below 100 parts-per-trillion, using a simple solid-phase extraction technique. Application of the technique for rapid screening of drugs of abuse in urine is demonstrated where solid-phase extraction columns are utilized for sample pretreatment. Urine samples spiked with drugs such as cocaine, codeine, morphine, phencyclidine, and methadone, yield photoionization mass spectra consisting of parent molecular ions for the drugs with a few noninterfering ion signals from the matrix. The technique is evaluated and compared to other drug screening techniques such as enzyme-multiplied immunoassay.

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Chen, Yanfeng. "Analysis of Biological Molecules Using Stimulated Desorption Photoionization Mass Spectrometry". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14620.

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Surface-assisted laser desorption/ionization mass spectrometry (SALDI MS) is a novel technique for direct analysis of organic and biological molecules. Amino acids, dipeptides, and organoselenium compounds were successfully detected by SALDI on carbon and silicon surfaces. Surface effects, solvent effects, temperature effects and pH effects were studied. A possible mechanism of SALDI is proposed based on observed results. In general, stimulated desorption results in neutral yields that are much larger than ion yields. Thus, we have exploited and further developed laser desorption single photon ionization mass spectrometry (LD/SPI MS) as a means of examining biomolecules. The experimental results clearly demonstrate that LD/SPI MS is a very useful and fast analysis method with uniform selectivity and high sensitivity. Selenium (Se) is an essential ultra-trace element in the human body. In efforts to obtain more useful information of selenium metabolites in human urine, mass determination of unknown organoselenium compounds in biological matrices using SALDI MS was investigated. In another approach, several selenium metabolites in human urine were successfully detected by LD/SPI MS. A HPLC-MS/MS method was also developed for a quantitative case study of selenium metabolites in human urine after ingestion of selenomethionine. Low-energy electrons (LEE, 3-20 eV) have been shown to induce single and double strand breaks (SSB and DSB) in plasmid DNA. To understand the genotoxic effects due to secondary species of high-energy radiation, we investigate the role of transient negative ions and the specificity in LEE-DNA damage by examining the neutral product yields using low electron stimulated dissociation SPI MS. The neutral yields as a function of incident electron energy are also correlated with the SSBs and DSBs measured using post-irradiation gel electrophoresis. The results provide further insight concerning the mechanisms of LEE-induced damage to DNA. Overall, this research provided an in-depth understanding of non-thermal surface processes and the development of new mass spectrometric techniques for the analysis of biomolecules.

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Burns, Kimberly Ann. "Coupled multi-group neutron photon transport for the simulation of high-resolution gamma-ray spectroscopy applications". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29737.

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Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Hertel, Nolan; Committee Member: Kulp, William David; Committee Member: Lee, Eva; Committee Member: Pagh, Richard; Committee Member: Petrovic, Bojan; Committee Member: Rahnema, Farzad; Committee Member: Smith, Eric; Committee Member: Wang, Chris. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Knie, André [Verfasser]. "Photon induced inner-shell excitation processes of nitrous oxide probed by angle resolved fluorescence and Auger-Electron spectrometry / André Knie". Kassel : Kassel University Press, 2013. http://d-nb.info/1056946180/34.

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Ben, Ltaief Ltaief [Verfasser]. "Interatomic Coulombic decay in noble gas clusters of varying sizes investigated by photon-induced (dispersed) ﬂuorescence spectrometry / Ltaief Ben Ltaief". Kassel : Universitätsbibliothek Kassel, 2018. http://d-nb.info/1162155019/34.

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Habib, Amr. "Détecteurs radiologiques grande surface, multi-énergie". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT055.

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L'objectif de la thèse est de proposer une solution pour un circuit intégré matriciel pour l'imagerie de rayons X fonctionnant, soit en mode spectrométrique où l'énergie de chaque photon X est mesurée, soit en mode d'intégration de charges où l'énergie totale déposée par les rayons X pendant une image est mesurée, la solution devant être à terme compatible avec un détecteur de grande surface typiquement de 20 cm x 20 cm. Un circuit de test (ASIC), ‘Sphinx' de 20 x 20 pixels au pas de 200 µm x 200 µm, en technologie CMOS 0.13 µm a été conçu pour servir de preuve du concept proposé. L'architecture de pixel retenue permet la quantification de la charge incidente par des paquets de contre-charges aussi bas que 100 électrons, ces contre-charges étant comptabilisées, soit pour chaque photon X (mode spectrométrique), soit pour la totalité des photons détectés pendant une image (mode intégration). Les premières mesures de caractérisation prouvent la validité du concept avec de bonnes performances en termes de consommation, bruit et linéarité. Une partie des pixels est dédiée à la détection directe des rayons X, ceux-ci étant alors convertis en charges électriques dans un semi-conducteur, tel que CdZnTe par exemple, lequel semiconducteur est couplé pixel à pixel à l'ASIC. Une autre partie des pixels est dédiée à la détection indirecte des rayons X, ceux-ci étant alors convertis en photons visibles dans une couche scintillatrice, telle CsI : Tl par exemple, et chaque pixel de l'ASIC possédant alors une photodiode. Pour ce dernier mode, de nouvelles formes de photodiodes rapides et peu capacitives ont de plus été conçues, simulées, et fabriquées en technologie CMOS 0.13 µm sur un autre ASIC. Enfin, la thèse se conclut en proposant des idées d'amélioration de performances à réaliser potentiellement dans un futur prototype
The objective of the thesis is to propose a solution for a 2D integrated circuit X-ray imager working, either in spectrometric mode where each X photon energy is measured, or in charge integration mode where the total energy deposited by X-ray during an image is measured, the solution being compatible with large area detectors typically of 20 cm x 20 cm. A proof of concept prototype ASIC 'Sphinx' was designed and fabricated in CMOS 0.13 µm technology; the ASIC being formed of a matrix of 20 x 20 pixels with a 200 µm pixel pitch. The designed architecture allows the quantification of the incoming charge through the use of counter-charge packets as low as 100 electrons. The injected packets are counted for each X photon (in the spectrometric photon counting mode), or for all charges integrated during the image period (in charge integration mode). First characterization measurements prove the validity of the concept with good performance in terms of power consumption, noise, and linearity. A first part of the ASIC is dedicated to X-ray direct detection where a semiconductor, e.g. CdZnTe, hybridized to the ASIC's pixels converts X-photons to electrical charge. Another part of the ASIC is dedicated indirect X-ray detection where a scintillator, e.g. CsI:Tl, is used to convert X-photons to visible photons which are then detected by in-pixel photodiodes. For the latter mode, new forms of photodiodes characterized by fast detection and low capacity were designed, simulated, and fabricated in CMOS 0.13 µm technology on a different ASIC. Finally, the thesis concludes with proposing performance enhancing ideas to be potentially implemented in a future prototype

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Varga, János [Verfasser], e Armin [Akademischer Betreuer] Reller. "Application of Thermal Analysis: Single Photon Ionization Time-of-Flight Mass Spectrometry for Studies of Inorganic Clusters and Ionic Liquids / János Varga ; Betreuer: Armin Reller". Augsburg : Universität Augsburg, 2017. http://d-nb.info/114105390X/34.

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Nazih, Abdelhamid. "Applications de la spectroscopie par corrélation de photons à : 1) la granulométrie des imbrûlés : 2) la vélocimétrie". Rouen, 1989. http://www.theses.fr/1989ROUES030.

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Mesure de la distribution granulométrique de particules de suies dans un tunnel de dilution. Application d'une méthode vélocimétrique basée sur l'annulation de la fonction de corrélation de l'intensité à des temps finis. Bon accord des résultats expérimentaux et des prévisions théoriques

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Zahir, Mostafa Lokman. "Nouvelles références en énergie X et gamma inférieures à 100 keV établies à l'aide de calorimètres magnétiques ultra haute résolution". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP125.

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Les raies X et gamma émis par des radionucléides peuvent être utilisées pour étalonner l'échelle en énergie des détecteurs à dispersion d'énergie. C'est le cas notamment pour les détecteurs cryogéniques qui offrent une excellente résolution, mais présentent des non-linéarités qu'il faut corriger. Afin d'étalonner ces détecteurs avec précision en dessous de 200 keV, il est nécessaire de disposer de rayons X et gamma ayant une incertitude de l'ordre de 0,1 eV. Or, les énergies des photons gamma recommandées respectant ce critère sont rares ou basées sur une seule mesure expérimentale. L'objectif principal de cette thèse est de mesurer avec une excellente résolution des photons gamma en dessous de 200 keV pour améliorer les incertitudes sur leurs énergies à environ 0,1eV. Pour répondre à cet objectif, un nouveau détecteur cryogénique a été conçu. C'est un calorimètre métallique magnétique (Metallic Magnetic Calorimeter, MMC) doté de huit absorbeurs en or de 50 µm d'épaisseur sur une surface totale de 8,4 mm². Un montage a été réalisé pour accueillir quatre puces MMC, deux puces SQUID assurant la lecture des MMC et les circuits imprimés pour les connecter aux câbles du réfrigérateur à dilution qui sert à les refroidir à leur température de fonctionnement autour de 15 mK. De plus, le montage comporte un passeur cryogénique de sources radioactives, spécialement réalisé pour fonctionner à très basse température et pouvoir mesurer jusqu'à quatre sources séquentiellement. Les sources mesurées sont des mélanges de plusieurs radionucléides : trois radionucléides étalon utilisés pour corriger la non-linéarité du MMC (169Yb, 57Co et 153Gd) et sept radionucléides pour mesurer leurs énergies X et gamma avec une très faible incertitude (109Cd, 133Ba 155Eu, 210Pb, 239Np, 241Am et 243Am). Les mélanges entre radionucléides ont été choisis par simulations Monte Carlo pour minimiser les interférences spectrales. L'169Yb a été produit par irradiation d'une feuille de thulium avec des deutérons auprès du cyclotron Arronax.Deux sessions de mesure indépendantes sur deux lots de quatre sources ont été effectuées à environ 16 mK, avec des conditions de régulation de température différentes. La résolution en énergie du détecteur est de 15 eV à 36 eV entre 0 keV et 200 keV. La non-linéarité de chaque absorbeur a été corrigée avec les raies des radionucléides étalons et un polynôme de second degré. Les énergies X et gamma mesurées ont été analysées et combinées par différentes méthodes. Quelle que soit la session de mesure et la méthode d'analyse utilisée, les énergies obtenues sont cohérentes entre elles, seules les incertitudes diffèrent. Au final, les énergies de 15 raies gamma ont été mesurées et pour 14 d'entre elles, l'incertitude obtenue, environ 0,2 eV, est plus faible que celle des valeurs recommandées. Huit énergies de photons X Kα ont également été mesurées ; pour ces raies mieux connues, un très bon accord est observé avec les valeurs recommandées, validant ainsi la méthodologie utilisée
The X and gamma rays emitted by radionuclides can be used to calibrate the energy scale of energy-dispersive detectors. This is particularly the case for cryogenic detectors, which offer excellent resolution but have non-linearities that need to be corrected. In order to calibrate these detectors accurately below 200 keV, it is necessary to have X-rays and gamma rays with an uncertainty of the order of 0.1 eV. However, recommended gamma-ray photon energies meeting this criterion are rare or based on a single experimental measurement. The main objective of this thesis is to measure gamma photons below 200 keV with excellent resolution in order to improve the uncertainties on their energies to around 0.1 eV. To meet this objective, a new cryogenic detector has been designed. It is a Metallic Magnetic Calorimeter (MMC) with eight 50 µm-thick gold absorbers covering a total surface area of 8.4 mm². An assembly was built to house: four MMC chips, two SQUID chips for reading-out the MMCs, and the printed circuits to connect them to the cables of the dilution refrigerator. The set-up also includes a cryogenic radioactive source sampler, specially designed to operate at very low temperatures and to measure up to four sources sequentially. The sources measured are mixtures of several radionuclides: three standard radionuclides used to correct the non-linearity of the MMC (169Yb, 57Co and 153Gd) and seven radionuclides used to measure their X and gamma energies with very low uncertainty (109Cd, 133Ba, 155Eu, 210Pb, 239Np, 241Am and 243Am). Mixtures of radionuclides in the sources were chosen by Monte Carlo simulations to minimise spectral interference. Ytterbium-169 was produced by irradiating a thulium foil with deuterons at the Arronax cyclotron.Two independent measurement sessions on two set of four sources were carried out at around 16 mK during two weeks, with different temperature control conditions. The energy resolution of the detector is 15 eV to 36 eV for gamma-rays between 0 keV and 200 keV. The non-linearity of each absorber was corrected using the lines of the standard radionuclides and a second-degree polynomial. The X-ray and gamma-ray energies measured were analysed and combined using various methods. Regardless ofthe measurement session and analysis method used, the energies obtained are consistent with each other, with only the uncertainties differing. In the end, the energies of 15 gamma-ray lines were measured and for 14 of them, the uncertainty obtained, around 0.2 eV, is lower than the recommended values. Eight Kα X-ray photon energies were also measured; for these well-known lines, very good agreement was observed with the recommended values, thus validating the methodology used in the work presented

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Adam, Thomas [Verfasser], Ralf [Akademischer Betreuer] Zimmermann, Antonius [Akademischer Betreuer] Kettrup e Harun [Akademischer Betreuer] Parlar. "Investigation of Tobacco Pyrolysis Gases and Puff-by-puff Resolved Cigarette Smoke by Single Photon Ionisation (SPI) – Time-of-flight Mass Spectrometry (TOFMS) / Thomas Adam. Gutachter: Antonius Kettrup ; Harun Parlar. Betreuer: Ralf Zimmermann". München : Universitätsbibliothek der TU München, 2006. http://d-nb.info/1058140760/34.

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Livros sobre o assunto "Photon spectrometry"

J, Laureijs R., ed. PHT--the imaging photo-polarimeter. Noordwijk, The Netherlands: ESA Publications, 2003.

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United States. National Aeronautics and Space Administration., ed. A rare gas optics-free absolute photon flux and energy analyzer for solar and planetary observations: Final report. Los Angeles, Calif: Dept. of Physics and Space Sciences Center, University of Southern California, 1994.

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United States. National Aeronautics and Space Administration., ed. A rare gas optics-free absolute photon flux and energy analyzer to provide absolute photoionization rates of inflowing interstellar neutrals: Final report. Washington, DC: National Aeronautics and Space Administration, 1994.

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Kroto, H. W. Molecular rotation spectra. Mineola, N.Y: Dover Publications, 2003.

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Kroto, H. W. Molecular rotation spectra. New York: Dover, 1992.

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Sobelʹman, I. I. Atomic spectra and radiative transitions. 2^a ed. Berlin: Springer, 1996.

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Sobelʹman, I. I. Atomic spectra and radiative transitions. 2^a ed. Berlin: Springer-Verlag, 1992.

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Capítulos de livros sobre o assunto "Photon spectrometry"

Goidenko, I., L. Labzowsky, A. Nefiodov, G. Plunien, G. Soff e S. Zschocke. "Evaluation of the Two-Photon Self-Energy Correction for Hydrogenlike Ions". In Atomic Physics at Accelerators: Mass Spectrometry, 397–400. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-015-1270-1_40.

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Klusoň, J. "Monte Carlo Simulations of Photon Field Characteristics for In Situ Gamma Spectrometry Applications". In Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications, 339–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/978-3-642-18211-2_54.

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Dong, F., E. R. Bernstein e J. J. Rocca. "Single-Photon Ionization Soft-X-Ray Laser Mass Spectrometry of Potential Hydrogen Storage Materials". In Springer Proceedings in Physics, 347–52. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-1186-0_39.

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Kleinknecht, Konrad, e Ulrich Uwer. "Symmetry Violations and Quark Flavour Physics". In Particle Physics Reference Library, 519–623. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-38207-0_9.

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AbstractOne of the surprising facts in our present understanding of the development of the Universe is the complete absence of “primordial” antimatter from the Big Bang about 13.7 billion years ago. The detection of charged cosmic-ray particles by magnetic spectrometers borne by balloons, satellites, and the space shuttle has shown no evidence for such primordial (high-energy) antibaryons; nor has the search for gamma rays from antimatter–matter annihilation yielded any such observation. In the early phases of the expanding Universe, a hot (1032 K) and dense plasma of quarks, antiquarks, leptons, antileptons and photons coexisted in equilibrium. This plasma expanded and cooled down, and matter and antimatter could recombine and annihilate into photons. If all interactions were symmetric with respect to matter and antimatter, and if baryon and lepton numbers were conserved, then all particles would finally convert to photons, and the expansion of the Universe would shift the wavelength of these photons to the far infrared region.

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Beechert, Jacqueline, Hadar Lazar e Albert Y. Shih. "Germanium Detectors for MeV Gamma-Ray Astrophysics with the Compton Spectrometer and Imager". In X-ray Photon Processing Detectors, 225–48. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-35241-6_10.

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Mochnacki, S. W., S. Chew, W. Kunowski, F. Hawker, K. Kamper, D. Blyth, L. Zerafa e A. Platzer. "The DDO Photon-Counting Spectrometer: A Well-Dressed Shectograph". In Instrumentation and Research Programmes for Small Telescopes, 461–62. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-010-9433-7_95.

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Hnatiuk, H. J., K. A. McGreer e J. N. Broughton. "An Integrated Optical Spectrometer for WDM". In Applications of Photonic Technology 2, 373–78. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4757-9250-8_61.

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Chen, Tianze, Xiaohui Li, Ke Wang, CunFeng Wei, Lei Shuai, Xiaopan Jiang, Na Wang, Mian Wang e Long Wei. "A Readout Electronic System for a 3D Position-Sensitive CdZnTe Gamma-Ray Spectrometer Based on the CPRE10-32 Readout ASIC". In X-ray Photon Processing Detectors, 155–77. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-35241-6_8.

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Villemaire, André, Martin Chamberland e Jean Giroux. "MIPAS: A Fourier Transform Spectrometer for Limb Sounding of the Atmosphere". In Applications of Photonic Technology, 179–82. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4757-9247-8_35.

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Gray, L., J. Harron, C. Hersom, J. Freemantle, P. Shepherd e J. Miller. "Calibration of the CASI Airborne Imaging Spectrometer and Application to Generating Reflectance Imagery". In Applications of Photonic Technology 2, 655–60. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4757-9250-8_101.

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Trabalhos de conferências sobre o assunto "Photon spectrometry"

Besnard-Vauterin, C., B. Rapp e V. Blideanu. "Advancements in Active Photon Interrogation through Photo-neutron Spectrometry: Unveiling Nitrogen Signatures for Illicit Materials Detection". In 2024 IEEE Nuclear Science Symposium (NSS), Medical Imaging Conference (MIC) and Room Temperature Semiconductor Detector Conference (RTSD), 1. IEEE, 2024. http://dx.doi.org/10.1109/nss/mic/rtsd57108.2024.10656955.

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Tkaczyk, Tomasz S., Jiawei Lu e Haimu Cao. "Imaging Snapshot Spectrometers enabled with 2-Photon Polymerization based Additive Manufacturing". In Imaging Systems and Applications, IM1G.7. Washington, D.C.: Optica Publishing Group, 2024. http://dx.doi.org/10.1364/isa.2024.im1g.7.

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The work presents examples of two imaging spectrometers enabled with 2-Photon Polymerization 3D printing. The presented spectrometers are field integral devices and image reorganization is achieved with high density waveguide array (waveguide spectrometer) or multifaceted, multi-angle mirror array respectively (Image Mapping Spectrometer - IMS). Fabricated components allow void spaces between image points dedicated for spectral information. High precision and repeatability of the fabricated components simplifies system calibration, improved image quality allows and more compact systems implementations.

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Yevseyev, Igor V. "Polarization photon echo spectroscopy". In High Performance Optical Spectrometry, editado por Maksymilian Pluta, Aleksandra Kopystynska e Mariusz Szyjer. SPIE, 1993. http://dx.doi.org/10.1117/12.155678.

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Gadomska, Bozena, e Wojciech Gadomski. "Creation and detuning of the two-photon overtone state in crystals by biharmonic pumping". In High Performance Optical Spectrometry, editado por Maksymilian Pluta, Aleksandra Kopystynska e Mariusz Szyjer. SPIE, 1993. http://dx.doi.org/10.1117/12.155683.

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Travis, J. C., T. B. Lucatorto, J. Wen, J. D. Fassett e C. W. Clark. "Doppler-Free Resonance Ionization Mass Spectrometry of Beryllium". In Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.tub2.

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As originally conceived, resonance ionization mass spectrometry (RIMS) combined the elemental selectivity of resonance ionization (1) with the isotopic selectivity of mass spectrometry to improve the accuracy and sensitivity of conventional mass spectrometry (2). For many applications, especially quantitation by isotope dilution (3) , it is important that no isotopic selectivity accompany the resonance ionization process. This condition is easily met for all but a few elements of the periodic table (4), since the great majority of optical isotope shifts are small with respect to typical dye laser bandwidths and Doppler-broadened linewidths in common atom reservoirs. However, another class of problem exists for which it is desirable to achieve isotopically selective resonance ionization. These applications involve the detection of extremely, rare stable or radioactive isotopes in the presence of the major isotopic species of an element. Miller et al. (5) have explored the optical isotopic selectivity of the isotopes of Lu using a RIMS spectrometer equipped with a high-resolution (single-mode) continuous-wave (cw) laser. Cannon et al. (6) have measured an optical selectivity (defined below) of 800 for isotopes of Ba, using a RIMS spectrometer with two cw lasers. We have proposed the use of pulsed, two-photon, Doppler-free resonance ionization to extend the capability of conventional mass spectrometers to measure isotope ratios in excess of 1012 (7). Initial experimental results using this approach, for the isotopes 9Be and 10Be, are reported here.

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Behrens, R., H. Zutz e J. Busse. "D2.3 Spectrometry of Pulsed Photon Radiation". In SMSI 2021. AMA Service GmbH, Von-Münchhausen-Str. 49, 31515 Wunstorf, Germany, 2021. http://dx.doi.org/10.5162/smsi2021/d2.3.

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Glodz, M., e M. Krainska-Miszczak. "Quantum beat method with two-photon absorption scheme in hyperfine-structure investigation of highly excited2D j states of alkali metal atoms". In High Performance Optical Spectrometry, editado por Maksymilian Pluta, Aleksandra Kopystynska e Mariusz Szyjer. SPIE, 1993. http://dx.doi.org/10.1117/12.155648.

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Lubman, David M., Chung Hang Sin e Ho Ming Pang. "Analytical Applications Of Supercritical Fluid/Supersonic Beam Laser Ionization Mass Spectrometry". In Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.tua4.

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Supercritical fluids of CO2 and N2O are used as a means of solubilizing nonvolatile polynuclear aromatic hydrocarbons and small thermally labile biologicals for expansion into supersonic beams for mass spectrometry. The resulting expansion into vacuum results in internally ultracold molecules with sharp spectral features for unique identification in UV-VIS absorption spectroscopy. In this work laser resonant two-photon ionization is used as a means of selectively producing ions for detection in mass spectrometry where the first photon excites the molecule to a real resonant state and the second photon ionizes the molecule. Although ions are produced for mass spectrometry, the ionization cross section reflects the SO → S1 transition so that ionization spectroscopy can be used as a means of identifying molecules in a mass spectrometer. We have applied this method to detection of several PNAH's where supercritical fluid expansion was used to solubilize these molecules essentially at room temperature, i.e. without heating. In addition, small biological and pharmaceutical analogs have been examined and the effect of the supercritical fluid solvent is studied. Most recently supercritical ammonia has been investigated as a highly polar solvent for dissolving indoleamines, catecholamines and other polar biological species. The key to this experiment is a novel compact molecular beam apparatus for supercritical fluid injection which takes advantage of (a) efficient liquid N2 cryopumping of CO2 and (b) a special high-pressure pulsed valve. This valve is capable of operation up to 400 atm backpressure at 250°C. The combination of pulsed valve injection with cryopumping allows the use of a 150-200 μ orifice for high on-axis density and thus sensitivity. The resulting chamber pressure at 400 atm reservoir pressure is <2×10−5 torr so that the ions produced by R2PI can be detected and mass analyzed in a time-of-flight mass spectrometer. The future potential of this method is discussed and compared to the use of the laser desorption method for volatilizing labile compounds into jet expansions.

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Vink, H. J. P., J. P. R. Day, J. B. C. Volatier e M. D. Nijkerk. "Spectrometry: photon sorting at the speed of light". In SPIE Optical Systems Design, editado por Laurent Mazuray, Rolf Wartmann e Andrew P. Wood. SPIE, 2015. http://dx.doi.org/10.1117/12.2191294.

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Sośnicki’, Filip, Michał Mikołajczyk, Ali Golestani e Michał Karpiński. "Characterization of Energy-Time Entangled Photon Pairs by Time-Resolved Detection". In Laser Science. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/ls.2023.lm5f.6.

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We experimentally realize two-photon temporal imaging and dispersive Fourier spectrometry within a single optical setup. We measure the joint temporal and spectral intensities for the characterization of energy-time entangled photon pair.

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Relatórios de organizações sobre o assunto "Photon spectrometry"

Fairbank, W. M. Jr. [Photon burst mass spectrometry technique.] Final report. Office of Scientific and Technical Information (OSTI), abril de 1996. http://dx.doi.org/10.2172/212673.

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McDowell, W. J., e G. N. Case. Procedure for the determination of uranium on cellulose air-sampling filters by photon-electron-rejecting-alpha-liquid-scintillation spectrometry. Office of Scientific and Technical Information (OSTI), agosto de 1986. http://dx.doi.org/10.2172/5227746.

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Rimal, Dipak. Proton Form Factor Puzzle and the CEBAF Large Acceptance Spectrometer (CLAS) Two-Photon Exchange Experiment. Office of Scientific and Technical Information (OSTI), maio de 2014. http://dx.doi.org/10.2172/1346719.

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Frabetti, P., e et al. Expression of intention to continue the study of states containing heavy quarks using the wideband photon beam and the E687 multiparticle spectrometer. Office of Scientific and Technical Information (OSTI), outubro de 1990. http://dx.doi.org/10.2172/1156321.

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Butterweck, Gernot, Alberto Stabilini, Benno Bucher, David Breitenmoser, Ladislaus Rybach, Cristina Poretti, Stéphane Maillard et al. Aeroradiometric measurements in the framework of the swiss exercise ARM23. Paul Scherrer Institute, PSI, março de 2024. http://dx.doi.org/10.55402/psi:60054.

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The flights of the civil (ARM23c) and military (ARM23m) parts of the exercise were performedbetween June 19th and 23rd and between September 11th and September 15th,respectively. The measuring system RLL001 was employed for all measurements. As usual, during the civil exercise the environs of some of the Swiss nuclear power plants were screened, on behalf of the Swiss Nuclear Safety Inspectorate (ENSI). At the site of the nuclear power plant Gösgen (KKG) with its pressurized water reactor, the activation products of the primary coolant loop are kept in the well shielded reactor building, thus generating no elevated readings neither on the premises nor in the vicinity of the power plant. The nuclear power plant of Mühleberg (KKM) is now being decommissioned. During this phase, activated components are temporarily stored and processed on the plant premises. The dose rate produced by these components, easily detected and identified with the Swiss airborne gamma spectrometry system, is nevertheless very modest and closely monitored by the Swiss Nuclear Safety Inspectorate (ENSI). Search exercises for radionuclide sources were performed in both parts of ARM23. The operational software of the RLL systems was able to detect the radionuclide sources placed in military training areas. The Man-Made Gross-Count (MMGC) ratio demonstrated a good sensitivity for the identification of radionuclide sources. Nevertheless, a weak radionuclide source placed in the field of view of the helicopter (300 m x 300 m at a ground clearance of 100 m) together with a much stronger radionuclide source emitting higher energy photons was obscured due to Compton scattered photons and therefore could not be detected. Measurements of two teams using drones equipped with radiation monitors demonstrated that low flying drones (ground clearance below 10 m) can be a valuable and complementary tool to identify sources and to further reduce the target area to be searched with ground teams. An altitude profile over Lake Constance confirmed the already observed influence of airborne radon progeny on the determination of cosmic and background corrections. Background flights were performed over several Swiss regions. Besides attenuation effects of water bodies, variations of natural radionuclide content could be observed. A new flight strategy in alpine topography was tested near the Swiss mountain Chrüz. Following contour lines of the topography reduces the necessity for drastic flight altitude changes compared to the parallel line pattern normally used, but is much more challenging for the pilots.

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