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Статті в журналах з теми "X-ray photons":

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Reusch, Tobias, Markus Osterhoff, Johannes Agricola, and Tim Salditt. "Pulse-resolved multi-photon X-ray detection at 31 MHz based on a quadrant avalanche photodiode." Journal of Synchrotron Radiation 21, no. 4 (June 3, 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.
2

Zhao, Di, Pengxian You, Jing Yang, Junhong Yu, Hang Zhang, Min Liao, and Jianbo Hu. "A Highly Stable-Output Kilohertz Femtosecond Hard X-ray Pulse Source for Ultrafast X-ray Diffraction." Applied Sciences 12, no. 9 (May 7, 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.
3

Saá Hernández, Ángela, Diego González-Díaz, Pablo Villanueva, Carlos Azevedo, and Marcos Seoane. "A new imaging technology based on Compton X-ray scattering." Journal of Synchrotron Radiation 28, no. 5 (July 22, 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.
4

Song, Sanghoon, Roberto Alonso-Mori, Matthieu Chollet, Yiping Feng, James M. Glownia, Henrik T. Lemke, Marcin Sikorski, et al. "Measurement of the absolute number of photons of the hard X-ray beamline at the Linac Coherent Light Source." Journal of Synchrotron Radiation 26, no. 2 (February 11, 2019): 320–27. http://dx.doi.org/10.1107/s1600577519000250.

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X-ray free-electron lasers provide intense pulses of coherent X-rays with a short pulse duration. These sources are chaotic by nature and therefore, to be used at their full potential, require that every X-ray pulse is characterized in terms of various relevant properties such as intensity, photon energy, position and timing. Diagnostics are for example installed on an X-ray beamline to specifically monitor the intensity of individual X-ray pulses. To date, these can however only provide a single-shot value of the relative number of photons per shot. Here are reported measurements made in January 2015 of the absolute number of photons in the hard X-ray regime at LCLS which is typically 3.5 × 1011 photons shot−1 between 6 and 9.5 keV at the X-ray Pump–Probe instrument. Moreover, an average transmission of ≈62% of the hard X-ray beamline over this energy range is measured and the third-harmonic content of ≈0.47% below 9 keV is characterized.
5

Pickford Scienti, Oliver L. P. Pickford, and 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, no. 9 (May 1, 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.
6

Feranchuk, Ilya D., Oleg D. Skoromnik, and Quang San Nguyen. "Method of the equivalent photons for modulated electron beam." Journal of the Belarusian State University. Physics, no. 3 (October 7, 2020): 24–31. http://dx.doi.org/10.33581/2520-2243-2020-3-24-31.

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It is shown in this work that electromagnetic self-field of the periodically density modulated electron bunch can be considered as the beam of the equivalent photons (pseudo-photons), collimated along the electron velocity. Pseudo-photon spectrum includes both the incoherent contribution being proportional to number of electrons in the bunch and the coherent part with the sharp maximum corresponding the modulation frequency. Method of the equivalent photons can be applied for description of the interaction between the electron bunch and a crystal that leads to generation of the coherent parametric X-ray radiation by the modulated bunches exited from the undulator of the X-ray free electron laser. It provides the possibility to obtain the X-ray pulses directed at the large angle to the electron velocity where intensity of the background radiation essentially decreased. It is defined the conditions when the spectral and angular distributions of the coherent pseudo-photons can be compared with the analogous values for the pulses of the X-ray laser.
7

Hu, Kun, Matthew G. Baring, Alice K. Harding, and Zorawar Wadiasingh. "High-energy Photon Opacity in the Twisted Magnetospheres of Magnetars." Astrophysical Journal 940, no. 1 (November 1, 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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Kutukova, Kristina, Bartlomiej Lechowski, Joerg Grenzer, Peter Krueger, André Clausner, and Ehrenfried Zschech. "Laboratory High-Contrast X-ray Microscopy of Copper Nanostructures Enabled by a Liquid-Metal-Jet X-ray Source." Nanomaterials 14, no. 5 (February 29, 2024): 448. http://dx.doi.org/10.3390/nano14050448.

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High-resolution imaging of Cu/low-k on-chip interconnect stacks in advanced microelectronic products is demonstrated using full-field transmission X-ray microscopy (TXM). The comparison of two lens-based laboratory X-ray microscopes that are operated at two different photon energies, 8.0 keV and 9.2 keV, shows a contrast enhancement for imaging of copper nanostructures embedded in insulating organosilicate glass of a factor of 5 if 9.2 keV photons are used. Photons with this energy (Ga-Kα radiation) are generated from a Ga-containing target of a laboratory X-ray source applying the liquid-metal-jet technology. The 5 times higher contrast compared to the use of Cu-Kα radiation (8.0 keV photon energy) from a rotating anode X-ray source is caused by the fact that the energy of the Ga-Kα emission line is slightly higher than that of the Cu-K absorption edge (9.0 keV photon energy). The use of Ga-Kα radiation is of particular advantage for imaging of copper interconnects with dimensions from several 100 nm down to several 10 nm in a Cu/SiO2 or Cu/low-k backend-of-line stack. Physical failure analysis and reliability engineering in the semiconductor industry will benefit from high-contrast X-ray images of sub-μm copper structures in microchips.
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Lewis, Cale E., and Mini Das. "Spectral Signatures of X-ray Scatter Using Energy-Resolving Photon-Counting Detectors." Sensors 19, no. 22 (November 18, 2019): 5022. http://dx.doi.org/10.3390/s19225022.

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Energy-resolving photon-counting detectors (PCDs) separate photons from a polychromatic X-ray source into a number of separate energy bins. This spectral information from PCDs would allow advancements in X-ray imaging, such as improving image contrast, quantitative imaging, and material identification and characterization. However, aspects like detector spectral distortions and scattered photons from the object can impede these advantages if left unaccounted for. Scattered X-ray photons act as noise in an image and reduce image contrast, thereby significantly hindering PCD utility. In this paper, we explore and outline several important characteristics of spectral X-ray scatter with examples of soft-material imaging (such as cancer imaging in mammography or explosives detection in airport security). Our results showed critical spectral signatures of scattered photons that depend on a few adjustable experimental factors. Additionally, energy bins over a large portion of the spectrum exhibit lower scatter-to-primary ratio in comparison to what would be expected when using a conventional energy-integrating detector. These important findings allow flexible choice of scatter-correction methods and energy-bin utilization when using PCDs. Our findings also propel the development of efficient spectral X-ray scatter correction methods for a wide range of PCD-based applications.
10

Rinkel, Jean, Debora Magalhães, Franz Wagner, Florian Meneau, and 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, no. 1 (January 1, 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.

Дисертації з теми "X-ray photons":

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 and 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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5

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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6

Su, Ting. "Quantitative material decomposition methods for X-ray spectral CT." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI056/document.

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La tomographie (CT) aux rayons X joue un rôle important dans l'imagerie non invasive depuis son introduction. Au cours des dernières années, de nombreuses avancées technologiques en tomographie par rayons X ont été observées, notamment la CT spectrale, qui utilise un détecteur à comptage de photons (PCD) pour discriminer les photons transmis correspondant à des bandes d'énergie sélectionnées afin d'obtenir une information spectrale. La CT spectrale permet de surmonter de nombreuses limitations des techniques précédentes et ouvre de nombreuses applications nouvelles, parmi lesquelles la décomposition quantitative des matériaux est le sujet le plus étudié. Un certain nombre de méthodes de décomposition des matériaux ont été rapportées et différents systèmes expérimentaux sont en cours de développement pour la CT spectrale. Selon le type de données sur lequel l'étape de décomposition fonctionne, nous avons les méthodes du domaine des projections (décomposition avant reconstruction) et les méthodes du domaine de l'image reconstruite (décomposition après reconstruction). La décomposition couramment utilisée est basée sur le critère des moindres carrés, nommée proj-LS et méthode ima-LS. Cependant, le problème inverse de la décomposition du matériau est généralement mal posé et les mesures du CT spectral aux rayons X souffrent de bruits de comptage de photons de Poisson. Le critère des moindres carrés peut conduire à un surajustement des données de mesure bruitées. Dans le présent travail, nous avons proposé un critère de moindre log-carré pour la méthode du domaine de projection afin de minimiser les erreurs sur le coefficient d'atténuation linéaire: méthode proj-LLS. De plus, pour réduire l'effet du bruit et lisser les images, nous avons proposé d'ajouter un terme de régularisation par patch pour pénaliser la somme des variations au carré dans chaque zone pour les décompositions des deux domaines, nommées proj-PR-LLS et ima -PR-LS méthode. Les performances des différentes méthodes ont été évaluées par des études de simulation avec des fantômes spécifiques pour différentes applications: (1) Application médicale: identification de l'iode et du calcium. Les résultats de la décomposition des méthodes proposées montrent que le calcium et l'iode peuvent être bien séparés et quantifiés par rapport aux tissus mous. (2) Application industrielle: tri des plastiques avec ou sans retardateur de flamme. Les résultats montrent que 3 types de matériaux ABS avec différents retardateurs de flamme peuvent être séparés lorsque l'épaisseur de l'échantillon est favorable. Enfin, nous avons simulé l'imagerie par CT spectrale avec un fantôme de PMMA rempli de solutions de Fe, Ca et K. Différents paramètres d'acquisition, c'est-à-dire le facteur d'exposition et le nombre de bandes d'énergie, ont été simulés pour étudier leur influence sur la performance de décomposition pour la détermination du fer
X-ray computed tomography (X-ray CT) plays an important part in non-invasive imaging since its introduction. During the past few years, numerous technological advances in X-ray CT have been observed, including spectral CT, which uses photon counting detectors (PCDs) to discriminate transmitted photons corresponding to selected energy bins in order to obtain spectral information with one single acquisition. Spectral CT enables us to overcome many limitations of the conventional CT techniques and opens up many new application possibilities, among which quantitative material decomposition is the hottest topic. A number of material decomposition methods have been reported and different experimental systems are under development for spectral CT. According to the type of data on which the decomposition step operates, we have projection domain method (decomposition before reconstruction) and image domain method (decomposition after reconstruction). The commonly used decomposition is based on least square criterion, named proj-LS and ima-LS method. However, the inverse problem of material decomposition is usually ill-posed and the X-ray spectral CT measurements suffer from Poisson photon counting noise. The standard LS criterion can lead to overfitting to the noisy measurement data. In the present work, we have proposed a least log-squares criterion for projection domain method to minimize the errors on linear attenuation coefficient: proj-LLS method. Furthermore, to reduce the effect of noise and enforce smoothness, we have proposed to add a patchwise regularization term to penalize the sum of the square variations within each patch for both projection domain and image domain decomposition, named proj-PR-LLS and ima-PR-LS method. The performances of the different methods were evaluated by spectral CT simulation studies with specific phantoms for different applications: (1) Medical application: iodine and calcium identification. The decomposition results of the proposed methods show that calcium and iodine can be well separated and quantified from soft tissues. (2) Industrial application: ABS-flame retardants (FR) plastic sorting. Results show that 3 kinds of ABS materials with different flame retardants can be separated when the sample thickness is favorable. Meanwhile, we simulated spectral CT imaging with a PMMA phantom filled with Fe, Ca and K solutions. Different acquisition parameters, i.e. exposure factor and number of energy bins were simulated to investigate their influence on the performance of the proposed methods for iron determination
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Galarowicz, Dale. "Instrumentation requirements for TREE Effects Data Collection at the Naval Postgraduate School Flash X-ray facility." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA237681.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 1990.
Thesis Advisor(s): Maruyama, X.K. Second Reader: Michael, S.N. "June 1990." Description based on title screen as viewed on March 24, 2010. DTIC Descriptor(s): Data Acquisition, Electronics, Facilities, Instrumentation, Integrated Systems, Noise (Electrical And Electromagnetic), Photons, Pulse Generators, Pulses, Radiation, Requirements, Scale, Transient Radiation Effects, Transients, Trees, Wafers, X Rays. DTIC Identifier(s): Transient radiation effects, Data acquisition, X ray apparatus, Electromagnetic pulses, Theses. Author(s) subject terms: EMP, IEMP, Flash X-Ray Instrumentation. Includes bibliographical references (p. 105-106). Also available in print.
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Manohar, Nivedh Harshan. "Effect of source x-ray energy spectra on the detection of fluorescence photons from gold nanoparticles." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/45970.

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X-ray fluorescence is a well-understood phenomenon in which irradiation of certain materials, such as gold, with x-rays causes the emission of secondary x-rays with characteristic energies. By performing computed tomography using these fluorescence x-rays, the material of interest can be imaged inside an object. Our research group has already demonstrated that x-ray fluorescence computed tomography (XFCT) imaging using a typical 110 kVp microfocus x-ray tube is feasible for a small animal-sized object containing a distribution of a solution of low concentration gold nanoparticles. The primary goal of this thesis work was to study the effect of source x-ray energy spectra on gold fluorescence detection using the XFCT system. A computational approach using the Monte Carlo method was used. First, a computational model was created using the Monte Carlo N-Particle (MCNP) transport code based on the experimental setup of the pre-existing XFCT system. Simulations were run to verify the validity of the MCNP model as an accurate representation of the actual system by means of comparison with experimentally-obtained data. Finally, the model was used for further purely computational work. In the MCNP model, the source spectrum was changed to reflect several theoretical and experimentally obtained options. The effect of these changes on gold fluorescence production was documented and quantified using the signal-to-background ratio and other qualitative measures. The results from this work provided clues on how to improve the detection of fluorescence photons from gold nanoparticle-loaded objects using the XFCT system. This will benefit future research on the development of the XFCT system in the context of making it more feasible for gold nanoparticle-based preclinical molecular imaging applications.
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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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Jackson, Gavin John. "Local adsorption structure determination of chemically-specific species using normal incidence X-ray standing wavefields." Thesis, University of Warwick, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343835.

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Книги з теми "X-ray photons":

1

A, Nowak Michael, and United States. National Aeronautics and Space Administration., eds. 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, and United States. National Aeronautics and Space Administration., eds. 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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3

A, Nowak Michael, and United States. National Aeronautics and Space Administration., eds. 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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4

Hansson, Conny, and Krzysztof Iniewski, eds. 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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5

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

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6

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

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7

United States. National Aeronautics and Space Administration., ed. 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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Fraser, G. W. X-ray detectors in astronomy. Cambridge: Cambridge University Press, 2009.

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9

Nars, François. X-ray. New York: powerHouse Books, 1999.

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10

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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Частини книг з теми "X-ray photons":

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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2

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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3

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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4

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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5

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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6

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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7

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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8

Aichinger, Horst, Joachim Dierker, Sigrid Joite-Barfuß, and 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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9

Aichinger, Horst, Joachim Dierker, Sigrid Joite-Barfuß, and 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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10

Tanyag, Rico Mayro P., Bruno Langbehn, Thomas Möller, and Daniela Rupp. "X-Ray and XUV Imaging of Helium Nanodroplets." In Topics in Applied Physics, 281–341. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-94896-2_7.

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AbstractX-ray and extreme ultraviolet (XUV) coherent diffractive imaging (CDI) have the advantage of producing high resolution images with current spatial resolution of tens of nanometers and temporal resolution of tens of femtoseconds. Modern developments in the production of coherent, ultra-bright, and ultra-short X-ray and XUV pulses have even enabled lensless, single-shot imaging of individual, transient, non-periodic objects. The data collected in this technique are diffraction images, which are intensity distributions of the scattered photons from the object. Superfluid helium droplets are ideal systems to study with CDI, since each droplet is unique on its own. It is also not immediately apparent what shapes the droplets would take or what structures are formed by dopant particles inside the droplet. In this chapter, we review the current state of research on helium droplets using CDI, particularly, the study of droplet shape deformation, the in-situ configurations of dopant nanostructures, and their dynamics after being excited by an intense laser pulse. Since CDI is a rather new technique for helium nanodroplet research, we also give a short introduction on this method and on the different light sources available for X-ray and XUV experiments.

Тези доповідей конференцій з теми "X-ray photons":

1

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

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2

Peters, Darryl W., and David N. Tomes. "X-ray lithography using conventional Novolak resists." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.fg3.

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A new laser-based soft x-ray lithographic technology is described that was developed to utilize conventional resists. It is well recognized that x rays offer better resolution, larger depth of field, larger process latitude, better critical dimension control, and immunity to typical clean room defects when compared to existing or emerging ultraviolet lithographic technologies. Previous x-ray technologies utilized low-yield electron impact tubes that produced hard x rays which were inefficiently absorbed in Novolak resists. This required special hypersensitive resist materials to achieve modest wafer throughputs at the expense of process latitude and process tolerance. Soft x rays (i.e., photon energies <1 keV) are efficiently absorbed in Novolak resist producing exposure sensitivities comparable with that achievable with ultraviolet photons (i.e., E 0 of 50–100 mJ/cm2). The high brightness Hampshire laser-based source is capable of producing 10–20 mW/cm2 yielding throughputs of twenty to forty wafers per hour depending on the resist's sensitivity. The source produces x rays from 0.8 to 2.0 nm with ~75% of the incident energy at wavelengths of 1.2-1.6 nm.
3

Choi, Seongwook, Sinyoung Park, Jung-Joon Min, Changho Lee, and Chulhong Kim. "X-ray induced acoustic computed tomography with a conventional x-ray contrast agent." In Photons Plus Ultrasound: Imaging and Sensing 2021, edited by Alexander A. Oraevsky and Lihong V. Wang. SPIE, 2021. http://dx.doi.org/10.1117/12.2576466.

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4

Burgdörfer, J., Y. Qiu, J. Wang, and 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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5

Johns, Paul C. "Medical x-ray imaging with scattered photons." In Opto-Canada: SPIE Regional Meeting on Optoelectronics, Photonics, and Imaging, edited by John C. Armitage. SPIE, 2017. http://dx.doi.org/10.1117/12.2283925.

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6

Schori, A., D. Borodin, K. Tamasaku, and 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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7

Shwartz, S., and 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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8

Tischler, J. Z., and B. C. Larson. "Time-resolved x-ray scattering using synchrotron sources." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oam.1991.md1.

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The pulsed time structure, high intensity, and tight collimation of synchrotron x-ray sources provide new opportunities for the investigation of transient physical properties. The time structure of the x-rays from a synchrotron source is typically 150-ps long pulses separated by 300 ns. By triggering an experiment in sync with these x-ray bursts, measurements can be made with 150-ps resolution as long as the x-ray detector can resolve the 300-ns pulse spacing. Using streak cameras, time resolution down to picoseconds can be achieved by time resolving within a single bunch since the peak intensity within a bunch is ~3 × 1016 photons/s. Next generation sources such as an undulator at the Advanced Photon Source will be 100–1000 times brighter than presently available sources. Nanosecond studies of pulsed laser melting and regrowth of Si and Ge are described, and related experiments involving high-heat flow and supercooled liquid structure are discussed. Single shot crystallography and experiments using the pulsed time structure for neV energy resolution x-ray diffraction via Mossbauer transitions are also discussed.
9

Kmetec, J. D., C. L. Gordon, B. E. Lemoff, and S. E. Harris. "Femtosecond generation of x-rays below 0.4 Å." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oam.1991.md3.

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We have observed substantial hard x-ray emission from a high-power femtosecond laser-produced plasma. The laser is based upon chirped pulse amplification in Ti:sapphire, and produces 60-mJ 125-fsec pulses at 10 Hz at 807 nm. This output is focused onto a heavy metal in vacuum. The focused intensity is approximately 5 × 1017 W/cm2, with a repetition rate of 10 Hz. We estimate an incident laser energy to x-ray energy conversion efficiency of ~10-5 when gold is the target material. The conversion efficiency includes only those x-rays that pass through 4.7 mm of aluminum (photon energy greater than ~35 keV). We have demonstrated that this is a sufficient number of x-ray photons (~1 μJ) to record an x-ray shadowgraph with one laser shot. We anticipate that the x-ray pulse duration is similar in time duration to the driving laser pulse.
10

Lei, Hao, Wei Zhang, Ibrahim Oraiqat, Issam El Naqa, and Xueding Wang. "2D x-ray dosimetry monitoring during radiotherapy using x-ray acoustic computed tomography (Conference Presentation)." In Photons Plus Ultrasound: Imaging and Sensing 2018, edited by Alexander A. Oraevsky and Lihong V. Wang. SPIE, 2018. http://dx.doi.org/10.1117/12.2289113.

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Звіти організацій з теми "X-ray photons":

1

Barty, C., and 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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2

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

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3

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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4

Yee, J. H., D. J. Mayhall, and 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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5

Thornton, Remington, En-Chuan Huang, and 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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6

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

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7

Simakov, S. Evaluation of the Prompt Gamma-ray Spectrum from Spontaneous Fission of 252Cf. IAEA Nuclear Data Section, February 2024. http://dx.doi.org/10.61092/iaea.bz1p-e3yc.

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The energy spectra, multiplicities and average energies of the prompt, total and delayed γ-rays accompanying the spontaneous fission of 252Cf were collected from the literature and dedicated databases. They were carefully analysed for consistency with a view to producing reference data for usage in various applications. This could be accomplished for the prompt fission gamma ray spectrum up to 20 MeV since dozens of measurements exist and reasonably agree. The prompt fission gamma ray spectrum (PFGS) was non-model evaluated by fitting the preselected experimental data with the help of the generalized least-squares (GLS) code GMA. The resulting spectrum could be considered as a reference for the γ-ray energies from 0.1 to 20 MeV with uncertainties varying between ≈ 3 and 25%. This reference gamma spectrum will be a substantial contribution to the precise and complete characterisation of the 252Cf source since the prompt fission neutron spectrum (PFNS), which has been accepted as a standard for a long time, has comparable uncertainties. The average gamma multiplicity and energy were also surveyed and used to derive the recommended values. The prompt X- and γ-ray energy spectra below ≈ 100 keV and delayed photon spectra in the whole energy range, as well as their multiplicities, are still seldomly and incompletely measured, that excepts an evaluation based on experimental data. The comparison with existing theoretical prompt and delayed 252Cf(s.f.) γ-spectra or with those presented in the major evaluated cross section libraries explored their incompleteness or deviations from the evaluated PFGS. The existing measurements of the pionic and muonic radioactivity of 252Cf(s.f.) and 235U(nth,f) were reviewed and the potential impact of gammas from the π0 decay on the high energy part of the PFGS was investigated.
8

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

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9

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), January 2022. http://dx.doi.org/10.2172/1842317.

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10

Friedman, N. Advanced photon source proposal for upgrading the radiation safety of x-ray labs. Office of Scientific and Technical Information (OSTI), July 1991. http://dx.doi.org/10.2172/376366.

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