Thematische Bibliographien / Photons X

Auswahl der wissenschaftlichen Literatur zum Thema „Photons X“

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Veröffentlicht am 7. Juli 2024

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Zeitschriftenartikel zum Thema "Photons X"

1

Bencheikh, Mohamed, Abdelmajid Maghnouj, Jaouad Tajmouati, Abdessamad Didi und Abdesslam Lamrabet. „Detailed Monte Carlo analysis of the secondary photons coming out of the therapeutic X-ray beam of linear accelerator“. Polish Journal of Medical Physics and Engineering 27, Nr. 2 (01.06.2021): 151–56. http://dx.doi.org/10.2478/pjmpe-2021-0018.

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Abstract External photon beam radiotherapy is often used in tumor treatment. The photons are generated from the target which had stricken by the primary electron beam (incident particles). The photon beam contains the primary photons coming directly from the target and secondary photons coming from the photon interactions with head component materials (scattered photons). Altogether is thereafter used in radiotherapy treatment. This Monte Carlo study aims to investigate and evaluate the secondary radiations (photons) in terms of fluence, energy fluence, spectral distribution, mean energy and angular spread distribution. The secondary photons, which contributed in radiotherapy treatment, are examined and evaluated in number (fluence) and energy. At the phantom surface, the secondary photons originated in the whole linac head are mainly coming from the primary collimator. In 0.45% of secondary photons coming from the whole linac head, the primary collimator contributes by 86% and they are more energetic. However, the flattening filter and the secondary collimator contribute together by less than 14% and their photons are less energetic and then can deteriorate the beam dosimetry quality. To improve the radiotherapy treatment quality, the number of photons of low energy should be as low as possible in the clinical beam. Our work can be a basic investigation to use in the improvement of linac head configuration and specially the beam modifiers.
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Pickford Scienti, Oliver L. P. Pickford, und Dimitra G. Darambara. „Demonstrating a Novel, Hidden Source of Spectral Distortion in X-ray Photon Counting Detectors and Assessing Novel Trigger Schemes Proposed to Avoid It“. Sensors 23, Nr. 9 (01.05.2023): 4445. http://dx.doi.org/10.3390/s23094445.

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X-ray photon counting spectral imaging (x-CSI) determines a detected photon’s energy by comparing the charge it induces with several thresholds, counting how many times each is crossed (the standard method, STD). This paper is the first to demonstrate that this approach can unexpectedly delete counts from the recorded energy spectrum under some clinically relevant conditions: a process we call negative counting. Four alternative counting schemes are proposed and simulated for a wide range of sensor geometries (pixel pitch 100–600 µm, sensor thickness 1–3 mm), number of thresholds (3, 5, 8, 24 and 130) and medically relevant X-ray fluxes (106–109 photons mm−2 s−1). Spectral efficiency and counting efficiency are calculated for each simulation. Performance gains are explained mechanistically and correlated well with the improved suppression of “negative counting”. The best performing scheme (Shift Register, SR) entirely eliminates negative counting, remaining close to an ideal scheme at fluxes of up to 108 photons mm−2 s−1. At the highest fluxes considered, the deviation from ideal behaviour is reduced by 2/3 in SR compared with STD. The results have significant implications both for generally improving spectral fidelity and as a possible path toward the 109 photons mm−2 s−1 goal in photon-counting CT.
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Saá Hernández, Ángela, Diego González-Díaz, Pablo Villanueva, Carlos Azevedo und Marcos Seoane. „A new imaging technology based on Compton X-ray scattering“. Journal of Synchrotron Radiation 28, Nr. 5 (22.07.2021): 1558–72. http://dx.doi.org/10.1107/s1600577521005919.

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A feasible implementation of a novel X-ray detector for highly energetic X-ray photons with a large solid angle coverage, optimal for the detection of Compton X-ray scattered photons, is described. The device consists of a 20 cm-thick sensitive volume filled with xenon at atmospheric pressure. When the Compton-scattered photons interact with the xenon, the released photoelectrons create clouds of secondary ionization, which are imaged using the electroluminescence produced in a custom-made multi-hole acrylic structure. Photon-by-photon counting can be achieved by processing the resulting image, taken in a continuous readout mode. Based on Geant4 simulations, by considering a realistic detector design and response, it is shown that photon rates up to at least 1011 photons s−1 on-sample (5 µm water-equivalent cell) can be processed, limited by the spatial diffusion of the photoelectrons in the gas. Illustratively, if making use of the Rose criterion and assuming the dose partitioning theorem, it is shown how such a detector would allow obtaining 3D images of 5 µm-size unstained cells in their native environment in about 24 h, with a resolution of 36 nm.
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Reusch, Tobias, Markus Osterhoff, Johannes Agricola und Tim Salditt. „Pulse-resolved multi-photon X-ray detection at 31 MHz based on a quadrant avalanche photodiode“. Journal of Synchrotron Radiation 21, Nr. 4 (03.06.2014): 708–15. http://dx.doi.org/10.1107/s1600577514006730.

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The technical realisation and the commissioning experiments of a high-speed X-ray detector based on a quadrant avalanche silicon photodiode and high-speed digitizers are described. The development is driven by the need for X-ray detectors dedicated to time-resolved diffraction and imaging experiments, ideally requiring pulse-resolved data processing at the synchrotron bunch repetition rate. By a novel multi-photon detection scheme, the exact number of X-ray photons within each X-ray pulse can be recorded. Commissioning experiments at beamlines P08 and P10 of the storage ring PETRA III, at DESY, Hamburg, Germany, have been used to validate the pulse-wise multi-photon counting scheme at bunch frequencies ≥31 MHz, enabling pulse-by-pulse readout during the PETRA III 240-bunch mode with single-photon detection capability. An X-ray flux of ≥3.7 × 109 photons s−1can be detected while still resolving individual photons at low count rates.
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Zhao, Di, Pengxian You, Jing Yang, Junhong Yu, Hang Zhang, Min Liao und Jianbo Hu. „A Highly Stable-Output Kilohertz Femtosecond Hard X-ray Pulse Source for Ultrafast X-ray Diffraction“. Applied Sciences 12, Nr. 9 (07.05.2022): 4723. http://dx.doi.org/10.3390/app12094723.

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Femtosecond hard X-ray pulses generated by laser-driven plasma sources are eminently suitable to probe structural dynamics due to the angstrom spatial resolution and sub-picosecond time resolution. However, the insufficient flux of X-ray photons and high pulse-to-pulse instability compared with the large-scale ultrashort X-ray source, such as X-ray free-electron laser and synchrotrons, largely restricts its applications. In this work, we have optimized automation control and mechanical designs to significantly enhance the reliability and photon flux in our femtosecond laser plasma-induced X-ray source. Specifically, the optimized source provides a reliable pulse-to-pulse stability with a fluctuation of less than 1% (root-mean-square) and a total flux of Cu-Kα X-ray photons above 1011 photons/s. To confirm its functionality, ultrafast X-ray diffraction experiments are conducted on two different samples and the high consistency with previous results verifies the system’s superior performance.
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Strnat, Sophia, Jonas Sommerfeldt, Vladimir Yerokhin, Wilko Middents, Thomas Stöhlker und Andrey Surzhykov. „Circular Polarimetry of Hard X-rays with Rayleigh Scattering“. Atoms 10, Nr. 4 (16.11.2022): 140. http://dx.doi.org/10.3390/atoms10040140.

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We present a theoretical investigation of the elastic Rayleigh scattering of X-rays by atomic targets. Special attention is paid to the question of how the polarization of the scattered photons is affected if the incident light is itself polarized. In particular, we found that the circular polarization of the incoming X-rays may lead to a remarkable modification of the linear polarization of the scattered photons. Based on this ’circular-to-linear-polarization-transfer’ and on the fact that the linear polarization of X-rays can be conveniently observed by solid-state Compton detectors, we argue that Rayleigh scattering may be used as a tool for circular polarimetry of hard X-rays. To illustrate our proposal, we performed detailed calculations of 145 and 500 keV circularly polarized photons scattered by lead atoms. Based on these calculations, we found that the photon scattering under large angles with respect to the incident beam direction is most favorable for the circular polarimetry of hard X-rays. In particular, for 500 keV photon energy and scattering angles around 70 deg we found a remarkable modification of the linear polarization of scattered light for the case when the incident radiation is circularly polarized.
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Hu, Kun, Matthew G. Baring, Alice K. Harding und Zorawar Wadiasingh. „High-energy Photon Opacity in the Twisted Magnetospheres of Magnetars“. Astrophysical Journal 940, Nr. 1 (01.11.2022): 91. http://dx.doi.org/10.3847/1538-4357/ac9611.

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Abstract Magnetars are neutron stars characterized by strong surface magnetic fields generally exceeding the quantum critical value of 44.1 TG. High-energy photons propagating in their magnetospheres can be attenuated by QED processes like photon splitting and magnetic pair creation. In this paper, we compute the opacities due to photon splitting and pair creation by photons emitted anywhere in the magnetosphere of a magnetar. Axisymmetric, twisted dipole field configurations embedded in the Schwarzschild metric are treated. The paper computes the maximum energies for photon transparency that permit propagation to infinity in curved spacetime. Special emphasis is given to cases where photons are generated along magnetic field loops and/or in polar regions; these cases directly relate to resonant inverse Compton scattering models for the hard X-ray emission from magnetars and Comptonized soft gamma-ray emission from giant flares. We find that increases in magnetospheric twists raise or lower photon opacities, depending on both the emission locale and the competition between field-line straightening and field strength enhancement. Consequently, given the implicit spectral transparency of hard X-ray bursts and persistent “tail” emission of magnetars, photon splitting considerations constrain their emission region locales and the twist angle of the magnetosphere; these constraints can be probed by future soft gamma-ray telescopes such as COSI and AMEGO. The inclusion of twists generally increases the opaque volume of pair creation by photons above its threshold, except when photons are emitted in polar regions and approximately parallel to the field.
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Shahmohammadi Beni, Mehrdad, Dragana Krstic, Dragoslav Nikezic und Kwan Ngok Yu. „Realistic dosimetry for studies on biological responses to X-rays and γ-rays“. Journal of Radiation Research 58, Nr. 5 (24.04.2017): 729–36. http://dx.doi.org/10.1093/jrr/rrx019.

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ABSTRACT A calibration coefficient R (= DA/DE) for photons was employed to characterize the photon dose in radiobiological experiments, where DA was the actual dose delivered to cells and DE was the dose recorded by an ionization chamber. R was determined using the Monte Carlo N-Particle version 5 (MCNP-5) code. Photons with (i) discrete energies, and (ii) continuous-energy distributions under different beam conditioning were considered. The four studied monoenergetic photons had energies E = 0.01, 0.1, 1 and 2 MeV. Photons with E = 0.01 MeV gave R values significantly different from unity, while those with E > 0.1 MeV gave R ≈ 1. Moreover, R decreased monotonically with increasing thickness of water medium above the cells for E = 0.01, 1 or 2 MeV due to energy loss of photons in the medium. For E = 0.1 MeV, the monotonic pattern no longer existed due to the dose delivered to the cells by electrons created through the photoelectric effect close to the medium–cell boundary. The continuous-energy distributions from the X-Rad 320 Biological Irradiator (voltage = 150 kV) were also studied under three different beam conditions: (a) F0: no filter used, (b) F1: using a 2 mm-thick Al filter, and (c) F2: using a filter made of (1.5 mm Al + 0.25 mm Cu + 0.75 mm Sn), giving mean output photon energies of 47.4, 57.3 and 102 keV, respectively. R varied from ~1.04 to ~1.28 for F0, from ~1.13 to ~1.21 for F1, and was very close to unity for F2.
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Rinkel, Jean, Debora Magalhães, Franz Wagner, Florian Meneau und Flavio Cesar Vicentin. „Detective quantum efficiency for photon-counting hybrid pixel detectors in the tender X-ray domain: application to Medipix3RX“. Journal of Synchrotron Radiation 23, Nr. 1 (01.01.2016): 206–13. http://dx.doi.org/10.1107/s1600577515020226.

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Synchrotron-radiation-based X-ray imaging techniques using tender X-rays are facing a growing demand, in particular to probe theKabsorption edges of low-Zelements. Here, a mathematical model has been developed for estimating the detective quantum efficiency (DQE) at zero spatial frequency in the tender X-ray energy range for photon-counting detectors by taking into account the influence of electronic noise. The experiments were carried out with a Medipix3RX ASIC bump-bonded to a 300 µm silicon sensor at the Soft X-ray Spectroscopy beamline (D04A-SXS) of the Brazilian Synchrotron Light Laboratory (LNLS, Campinas, Brazil). The results show that Medipix3RX can be used to develop new imaging modalities in the tender X-ray range for energies down to 2 keV. The efficiency and optimal DQE depend on the energy and flux of the photons. The optimal DQE values were found in the 7.9–8.6 keV photon energy range. The DQE deterioration for higher energies due to the lower absorption efficiency of the sensor and for lower energies due to the electronic noise has been quantified. The DQE for 3 keV photons and 1 × 104 photons pixel−1s−1is similar to that obtained with 19 keV photons. Based on our model, the use of Medipix3RX could be extended down to 2 keV which is crucial for coming applications in imaging techniques at modern synchrotron sources.
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Carvalho, A. M. G., D. H. C. Araújo, H. F. Canova, C. B. Rodella, D. H. Barrett, S. L. Cuffini, R. N. Costa und R. S. Nunes. „X-ray powder diffraction at the XRD1 beamline at LNLS“. Journal of Synchrotron Radiation 23, Nr. 6 (06.10.2016): 1501–6. http://dx.doi.org/10.1107/s1600577516012686.

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Various upgrades have been completed at the XRD1 beamline at the Brazilian synchrotron light source (LNLS). The upgrades are comprehensive, with changes to both hardware and software, now allowing users of the beamline to conduct X-ray powder diffraction experiments with faster data acquisition times and improved quality. The main beamline parameters and the results obtained for different standards are presented, showing the beamline ability of performing high-quality experiments in transmission geometry. XRD1 operates in the 5.5–14 keV range and has a photon flux of 7.8 × 109 photons s−1(with 100 mA) at 12 keV, which is one of the typical working energies. At 8 keV (the other typical working energy) the photon flux at the sample position is 3.4 × 1010 photons s−1and the energy resolution ΔE/E= 3 × 10−4.
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Dissertationen zum Thema "Photons X"

1

Emre, Eylem. „Scanning Imaging With High Energy Photons“. Master's thesis, Ankara : METU, 2003. http://etd.lib.metu.edu.tr/upload/1206614/index.pdf.

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Brink, Paul Louis. „Non-equilibrium superconductivity induced by X-ray photons“. Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260725.

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梁邦平 und Pong-ping Leung. „High energy photons from accretion powered X-ray binaries“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31233727.

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Leung, Pong-ping. „High energy photons from accretion powered X-ray binaries /“. [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13829853.

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Farquharson, Michael James. „Characterisation of bone tissue using coherently scattered x-ray photons“. Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243790.

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Chaput, Julien. „Étude d'un détecteur CMOS hybride à semi-conducteur et comptage de photons : application à l'imagerie X“. Clermont-Ferrand 1, 2005. http://www.theses.fr/2005CLF1MM11.

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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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Poggioli, Luc. „Étude de la fonction de structure du photon Fγ₂(x, Q²) à l'aide du détecteur CELLO“. Paris 11, 1988. http://www.theses.fr/1988PA112264.

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Thibaudeau, Christian. „Tomodensitométrie par comptage de photons avec discrimination en énergie“. Thèse, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/8337.

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Depuis l'avènement de la tomodensitométrie (TDM) au début des années 1970, la durée nécessaire à l'acquisition d'un jeu de données nécessaire à la reconstruction d'une image est passée de plusieurs jours à quelques centaines de millisecondes. Mis à part le progrès des composants mécaniques, électriques et électroniques, le principe de base implanté dans le tout premier prototype est toujours utilisé par les scanners d'aujourd'hui. Si le principe est resté le même, l'utilisation de l'imagerie TDM clinique a connu pour sa part une expansion fulgurante. Un nombre d'examens important, atteignant mondialement les centaines de millions par an au début des années 2000, commence alors à inquiéter la communauté scientifique et médicale. Si la dose administrée par examen reste relativement faible, les conséquences de cette exposition globale pourraient s'avérer fâcheuses. Parallèlement, les 15 dernières années ont vu l'apparition d'un nouveau type de détection. Ce détecteur, qui compte individuellement les photons X et mesure leur énergie, pourrait jouer un rôle important dans la quête de réduction de la dose. Même si ce nouveau développement n'a pas été motivé en réponse directe à l'accroissement de la dose, son avènement arrive à un moment très opportun. D'après la théorie, le seul fait d'acquérir la radiation incidente en utilisant cette approche permet une mesure moins bruitée. La nature spectrale de l'information recueillie ouvre aussi la porte à de nouvelles méthodes de traitement et d'analyse des images reconstruites. Dans la pratique, la fabrication de tels détecteurs n'est cependant pas chose facile et de nombreux impondérables ont fait leur apparition. L'influence des différentes caractéristiques de détection sur la qualité des images est aujourd'hui encore méconnue. Ce projet contient diverses contributions apportées au domaine de la TDM polyénergétique, en utilisant le concept de reconstruction d'images pour leitmotiv. Dans un premier temps, un modèle pragmatique et très différent des approches Monte Carlo existantes est proposé afin de reproduire de manière analytique une acquisition TDM spectrale. Un nouvel algorithme de reconstruction itératif adapté spécifiquement aux données polyénergétiques est ensuite présenté. Cet algorithme, unifiant les concepts éprouvés de décomposition en fonctions de base et de reconstruction statistique, permet de tirer pleinement parti de cette mesure particulière. Une approche de reconstruction différente, utilisant une représentation polaire de l'objet image, est aussi présentée. Celle-ci permet de diminuer grandement les exigences logicielles tout en réduisant les durées de reconstruction. L'influence de certaines caractéristiques de détection associées aux détecteurs spectraux est aussi étudiée, en mettant l'emphase sur les conséquences au niveau de la qualité des images reconstruites. Une méthode novatrice, permettant d'estimer le dépôt de dose à partir d'une acquisition polyénergétique, est finalement présentée.
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Mazal, Daniel Alejandro. „Radiothérapie stéréotaxique par petits faisceaux de rayons x de haute énergie : développement des moyens techniques et dosimétriques“. Toulouse 3, 1990. http://www.theses.fr/1990TOU30069.

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Ce travail porte sur le developpement des moyens techniques et dosimetriques necessaires a la mise en application de la radiotherapie stereotaxique, par convergence de petits faisceaux de photons (diametre compris entre 10 et 40 mm) de haute energie (6-25 mv), produits par un accelerateur lineaire. Ces irradiations sont employees pour le traitement de petits volumes cibles intracraniens (tumeurs, malformations arterioveineuses. . . ). Les aspects dosimetriques, mecaniques et informatiques ont ete analyses. Les caracteristiques dosimetriques specifiques des petits faisceaux de photons de haute energie sont liees au manque d'equilibre electronique. Le maximum des courbes de rendement en profondeur s'approche de la surface et le debit diminue de facon abrupte lorsque le diametre du faisceau diminue. Les profils des faisceaux ont des gradients eleves, par ex. Jusqu'a 30%/mm pour un faisceau de 10 mm de diametre a 23 mv. Les mesures ont ete faites par chambres d'ionisation, films, thermoluminescence et diodes; elles ont ete validees par calcul informatique en superposant des matrices de dispersion de dose generee par la methode de monte carlo. Les chambres et les films ont ete retenus pour la dosimetrie des faisceaux pour l'application clinique. L'utilisation des chambres d'ionisation cylindriques en les irradiant parallelement a leur axe principal a ete analysee. Un systeme additionnel de collimation et un reglage micrometrique de l'isocentrisme du systeme stereotaxique ont ete developpes. Un ensemble de logiciels a ete developpe pour la simulation des informations anatomiques, les calculs de distribution de dose dans des plans arbitraires et des histogrammes dose-volume. Ils ont ete utilises pour analyser l'incidence des parametres geometriques et physiques sur la distribution finale de dose, ainsi que pour les applications cliniques, qui ont debute en janvier 1990
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Bücher zum Thema "Photons X"

1

A, Nowak Michael, und United States. National Aeronautics and Space Administration., Hrsg. X-ray variability coherence: How to compute it, what it means, and how it constrains models of GX 339-4 and Cygnus X-1. [Washington, DC: National Aeronautics and Space Administration, 1997.

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A, Nowak Michael, und United States. National Aeronautics and Space Administration., Hrsg. X-ray variability coherence: How to compute it, what it means, and how it constrains models of GX 339-4 and Cygnus X-1. [Washington, DC: National Aeronautics and Space Administration, 1997.

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A, Nowak Michael, und United States. National Aeronautics and Space Administration., Hrsg. X-ray variability coherence: How to compute it, what it means, and how it constrains models of GX 339-4 and Cygnus X-1. [Washington, DC: National Aeronautics and Space Administration, 1997.

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United States. National Aeronautics and Space Administration., Hrsg. X-ray inverse Compton emission from the radio halo of M87: A thesis in astronomy. [University Park, Pa.]: Pennsylvania State University, The Graduate School, Dept. of Astronomy, 1985.

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Marenkov, O. S. Handbook of photon interaction coefficients in radioisotope-excited x-ray fluorescence analysis. New York: Nova Science Publishers, 1991.

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6

Hansson, Conny, und Krzysztof Iniewski, Hrsg. X-ray Photon Processing Detectors. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-35241-6.

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NATO Advanced Research Workshop on Electron-photon Interaction in Dense Media (2001 Yerevan, Armenia). Electron-photon interaction in dense media. Dordrecht: Kluwer Academic, 2002.

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Fraser, G. W. X-ray detectors in astronomy. Cambridge: Cambridge University Press, 1989.

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Fraser, G. W. X-ray detectors in astronomy. Cambridge [England]: Cambridge University Press, 1989.

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Landis, Tony. X-15 photo scrapbook. North Branch, Minn: Specialty, 2003.

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Buchteile zum Thema "Photons X"

1

Holland, Andrew. „X-ray CCDs“. In Observing Photons in Space, 443–53. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-7804-1_24.

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Porter, F. Scott. „X-ray calorimeters“. In Observing Photons in Space, 497–514. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-7804-1_28.

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Smith, David M. „Hard X-ray and gamma-ray detectors“. In Observing Photons in Space, 367–89. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-7804-1_21.

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Hurford, Gordon J. „X-ray imaging with collimators, masks and grids“. In Observing Photons in Space, 243–54. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-7804-1_12.

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Frauenfelder, Hans. „Scattering of Photons: X-Ray Diffraction“. In The Physics of Proteins, 341–61. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-1044-8_25.

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Culhane, J. Len. „X-ray astronomy: energies from 0.1 keV to 100 keV“. In Observing Photons in Space, 73–91. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-7804-1_4.

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Aichinger, Horst, Joachim Dierker, Sigrid Joite-Barfuß und Manfred Säbel. „Interaction of Photons with Matter“. In Radiation Exposure and Image Quality in X-Ray Diagnostic Radiology, 21–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11241-6_4.

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Aichinger, Horst, Joachim Dierker, Sigrid Joite-Barfuß und Manfred Säbel. „Interaction of Photons with Matter“. In Radiation Exposure and Image Quality in X-Ray Diagnostic Radiology, 15–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-09654-3_3.

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Margaritondo, Giorgio. „From Synchrotrons to FELs: How Photons are Produced; Beamline Optics and Beam Characteristics“. In X-Ray Absorption and X-Ray Emission Spectroscopy, 23–50. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch2.

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Stöhr, Joachim. „Production of X-Rays: From Virtual to Real Photons“. In Springer Tracts in Modern Physics, 61–117. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-20744-0_2.

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Konferenzberichte zum Thema "Photons X"

1

Peterman, D., M. Lemonnier und S. Megtert. „X-Ray Camera For Photons Counting“. In International Topical Meeting on Image Detection and Quality, herausgegeben von Lucien F. Guyot. SPIE, 1987. http://dx.doi.org/10.1117/12.966762.

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Lee, Peter H. Y., Donald E. Casperson und Gottfried T. Schappert. „Search for X-Rays Generated by Collisionless Multiphoton Processes“. In Short Wavelength Coherent Radiation: Generation and Applications. Washington, D.C.: Optica Publishing Group, 1988. http://dx.doi.org/10.1364/swcr.1988.hilim242.

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We have conducted photon counting experiments to search for x rays which may be generated by either collisionless multiphoton induced inner-shell processes or bremsstrahlung at high laser irradiance. Using KrF light at an irradiance ~ 3 x 1017 W/cm2 on low density Xe gas targets, we detect no prompt photons which are characteristic of these processes.
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Joblin, Tony. „Contrast in Time of Flight, Near Infrared Laser Imaging Through Turbid Media“. In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/cleo_europe.1996.cthq2.

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Ultrafast near infrared (NIR) lasers have been proposed as a tool for detection and diagnosis of breast disease. The advantage of using NIR photons is that they are non-ionising and hence provide a greater degree of patient safety than existing X-ray imaging methods. The investigation of NIR photon imaging techniques has also been pursued because NIR photons may be able to provide useful functional physiological and diagnostic information not present in X-ray images.
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Johns, Paul C. „Medical x-ray imaging with scattered photons“. In Opto-Canada: SPIE Regional Meeting on Optoelectronics, Photonics, and Imaging, herausgegeben von John C. Armitage. SPIE, 2017. http://dx.doi.org/10.1117/12.2283925.

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Schori, A., D. Borodin, K. Tamasaku und S. Shwartz. „Ghost Imaging with Paired X-ray Photons“. In CLEO: Applications and Technology. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/cleo_at.2018.jth2a.7.

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Shwartz, S., und S. E. Harris. „Polarization Entangled Photons at X-Ray Energies“. In Nonlinear Optics: Materials, Fundamentals and Applications. Washington, D.C.: OSA, 2011. http://dx.doi.org/10.1364/nlo.2011.nwc3.

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Aknin, Haim, und Sharon Shwartz. „Nanometric-scale phase contrast imaging with undetected x-ray photons“. In Quantum 2.0. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/quantum.2023.qth3a.2.

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We show that a system using down conversion of x-ray photons into optical photons together with the concept of quantum imaging with undetected photons can provide nanoscale resolution even for radiation sensitive samples.
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Burgdörfer, J., Y. Qiu, J. Wang und J. H. McGuire. „Double ionization of helium by photons and charged particles“. In X-RAY AND INNER-SHELL PROCESSES. ASCE, 1997. http://dx.doi.org/10.1063/1.52257.

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Filipponi, A., S. De Panfilis und A. Di Cicco. „Temperature Scanning Techniques with Tunable X-Ray Photons“. In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644680.

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Aknin, Haim, und Sharon Shwartz. „Quantum hard x-ray microscopy with undetected photons“. In Optical and Quantum Sensing and Precision Metrology II, herausgegeben von Selim M. Shahriar und Jacob Scheuer. SPIE, 2022. http://dx.doi.org/10.1117/12.2616980.

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Berichte der Organisationen zum Thema "Photons X"

1

Anisimov, Petr Mikhaylovich. From shy atoms and photons to quantum future of X-ray free electron lasers. Office of Scientific and Technical Information (OSTI), Februar 2015. http://dx.doi.org/10.2172/1170698.

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Barty, C., und F. Hartemann. T-REX: Thomson-Radiated Extreme X-rays Moving X-Ray Science into the ''Nuclear'' Applications Space with Thompson Scattered Photons. Office of Scientific and Technical Information (OSTI), September 2004. http://dx.doi.org/10.2172/15011627.

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Seltzer, Stephen. Calculations of fluence rates of unscattered x- and gamma-ray photons emerging from model spheres of special nuclear material. Gaithersburg, MD: National Institute of Standards and Technology, 2009. http://dx.doi.org/10.6028/nist.ir.7557.

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Yee, J. H., D. J. Mayhall und M. F. Bland. Theoretical Model for the EM Effects Induced by High-Energy Photons (Gamma, X-ray) in Dielectric Materials and Electronic Systems. Office of Scientific and Technical Information (OSTI), August 2001. http://dx.doi.org/10.2172/15004648.

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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, März 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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Thornton, Remington, En-Chuan Huang und Janardan Upadhyay. X-Ray Development Photos April 2023. Office of Scientific and Technical Information (OSTI), April 2023. http://dx.doi.org/10.2172/1972098.

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Thornton, Remington. X-Ray Development Photos Nov 2022. Office of Scientific and Technical Information (OSTI), Januar 2023. http://dx.doi.org/10.2172/1922732.

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Clymer, Bradley D., und Celeste B. Williams. X-Photon-to-Information Conversion Efficiency in Digital Telemammography. Fort Belvoir, VA: Defense Technical Information Center, Dezember 2000. http://dx.doi.org/10.21236/ada394007.

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Weber, F., P. Celliers, S. Moon, R. Snavely und L. Da Silva. Inner-Shell Photon-Ionized X-Ray Laser at 45(Angstrom). Office of Scientific and Technical Information (OSTI), Februar 2002. http://dx.doi.org/10.2172/15005449.

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Turnbull, David, Phil Franke, John Palastro, Ildar Begishev, Robert Boni, Jake Bromage, Andrew Howard et al. Advanced Photon Acceleration Schemes for Tunable XUV/Soft X-Ray Sources. Office of Scientific and Technical Information (OSTI), Januar 2022. http://dx.doi.org/10.2172/1842317.

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