WorldWideScience

Sample records for cardiac x-ray machine

  1. Absorbed and effective dose from periapical radiography by portable intraoral x-ray machine

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jeong Yeon; Han, Won Jeong; Kim, Eun Kyung [Dankook Univ. School of Dentistry, Seoul (Korea, Republic of)

    2007-09-15

    The purpose of this study was to measure the absorbed dose and to calculate the effective dose for periapical radiography done by portable intraoral x-ray machines. 14 full mouth, upper posterior and lower posterior periapical radiographs were taken by wall-type 1 and portable type 3 intraoral x-ray machines. Thermoluminescent dosemeters were placed at 23 sites at the layers of the tissue-equivalent ART woman phantom for dosimetry. Average tissue absorbed dose and radiation weighted dose were calculated for each major anatomical site. Effective dose was calculated using 2005 ICRP tissue weighted factors. On 14 full mouth periapical radiographs, the effective dose for wall-type x-ray machine was 30 Sv; for portable x-ray machines were 30 Sv, 22 Sv, 36 Sv. On upper posterior radiograph, the effective dose for wall-type x-ray machine was 4 Sv; for portable x-ray machines doses were 4 Sv, 3 Sv, 5 Sv. On lower posterior radiograph, the effective dose for wall type x-ray machine was 5 Sv; for portable x-ray machines doses were 4 Sv, 4 Sv, 5 Sv. Effective doses for periapical radiographs performed by portable intraoral x-ray machines were similar to doses for periapical radiographs taken by wall type intraoral x-ray machines.

  2. 3D X-ray imaging methods in support catheter ablations of cardiac arrhythmias.

    Science.gov (United States)

    Stárek, Zdeněk; Lehar, František; Jež, Jiří; Wolf, Jiří; Novák, Miroslav

    2014-10-01

    Cardiac arrhythmias are a very frequent illness. Pharmacotherapy is not very effective in persistent arrhythmias and brings along a number of risks. Catheter ablation has became an effective and curative treatment method over the past 20 years. To support complex arrhythmia ablations, the 3D X-ray cardiac cavities imaging is used, most frequently the 3D reconstruction of CT images. The 3D cardiac rotational angiography (3DRA) represents a modern method enabling to create CT like 3D images on a standard X-ray machine equipped with special software. Its advantage lies in the possibility to obtain images during the procedure, decreased radiation dose and reduction of amount of the contrast agent. The left atrium model is the one most frequently used for complex atrial arrhythmia ablations, particularly for atrial fibrillation. CT data allow for creation and segmentation of 3D models of all cardiac cavities. Recently, a research has been made proving the use of 3DRA to create 3D models of other cardiac (right ventricle, left ventricle, aorta) and non-cardiac structures (oesophagus). They can be used during catheter ablation of complex arrhythmias to improve orientation during the construction of 3D electroanatomic maps, directly fused with 3D electroanatomic systems and/or fused with fluoroscopy. An intensive development in the 3D model creation and use has taken place over the past years and they became routinely used during catheter ablations of arrhythmias, mainly atrial fibrillation ablation procedures. Further development may be anticipated in the future in both the creation and use of these models.

  3. The reduction methods of operator's radiation dose for portable dental X-ray machines

    OpenAIRE

    Jeong-Yeon Cho; Won-Jeong Han

    2012-01-01

    Objectives This study was aimed to investigate the methods to reduce operator's radiation dose when taking intraoral radiographs with portable dental X-ray machines. Materials and Methods Two kinds of portable dental X-ray machines (DX3000, Dexcowin and Rextar, Posdion) were used. Operator's radiation dose was measured with an 1,800 cc ionization chamber (RadCal Corp.) at the hand level of X-ray tubehead and at the operator's chest and waist levels with and without the backscatter s...

  4. Using a Robotic Arm for Echocardiography to X-ray Image Registration during Cardiac Catheterization Procedures

    OpenAIRE

    Ma, Yingliang; Penney, Graeme P.; Bos, Dennis; Frissen, Peter; De Fockert, George; Yao, Cheng; King, Andy; Gao, Gang; Rinaldi, Christopher Aldo; Razavi, Reza; Rhode, Kawal,

    2009-01-01

    International audience; We present an initial evaluation of a robotic arm for positioning a 3D echo probe during cardiac catheterization procedures. By tracking the robotic arm, X-ray table and X-ray C-arm, we are able to register the 3D echo images with live 2D X-ray images. In addition, we can also use tracking data from the robotic arm combined with system calibrations to create extended field of view 3D echo images. Both these features can be used for roadmapping to guide cardiac catheter...

  5. Motion compensated iterative reconstruction for cardiac X-ray tomography

    NARCIS (Netherlands)

    A.A. Isola (Alfonso)

    2010-01-01

    textabstractWithin this Ph.D. project, three-dimensional reconstruction methods for moving objects (with a focus on the human heart) from cone-beam X-ray projections using iterative reconstruction algorithms were developed and evaluated. This project was carried in collaboration with the Digital

  6. APPLICATION OF X-RAY DIFFRACTION AND BARKHAUSEN NOISE ANALYSIS FOR STABILITY CONTROL DURING MACHINING

    Directory of Open Access Journals (Sweden)

    Kamil Kolařík

    2011-07-01

    Full Text Available The contribution is focused on the recent experience of X-ray Diffraction Laboratory of the Czech Technical University in Prague and Department of Machining and Assembly of the Technical University of Liberec with industrial applications of X-ray diffraction residual stress measurement and Barkhausen noise analysis. Both methods are used for control and optimization of technological parameters during final surface machining of camshafts. They verify whether the required level of residual stresses in given subsurface areas was achieved and serve also as a fast output inspection of machine parts´ surface quality.

  7. The reduction methods of operator's radiation dose for portable dental X-ray machines

    Directory of Open Access Journals (Sweden)

    Jeong-Yeon Cho

    2012-08-01

    Full Text Available Objectives This study was aimed to investigate the methods to reduce operator's radiation dose when taking intraoral radiographs with portable dental X-ray machines. Materials and Methods Two kinds of portable dental X-ray machines (DX3000, Dexcowin and Rextar, Posdion were used. Operator's radiation dose was measured with an 1,800 cc ionization chamber (RadCal Corp. at the hand level of X-ray tubehead and at the operator's chest and waist levels with and without the backscatter shield. The operator's radiation dose at the hand level was measured with and without lead gloves and with long and short cones. Results The backscatter shield reduced operator's radiation dose at the hand level of X-ray tubehead to 23 - 32%, the lead gloves to 26 - 31%, and long cone to 48 - 52%. And the backscatter shield reduced operator's radiation dose at the operator's chest and waist levels to 0.1 - 37%. Conclusions When portable dental X-ray systems are used, it is recommended to select X-ray machine attached with a backscatter shield and a long cone and to wear the lead gloves.

  8. patient exposure around an x-ray diagnostic machine~a case study

    African Journals Online (AJOL)

    —ray machine with a tungsten anode at the out-patient department of the University College Hospital (UCH),. Ibadan, Nigeria. The machine is a GEC. Medical Apollo, Roentgen 501 with an X-ray tube made by Machlett at target angle of 16°.

  9. Machine learning applied to single-shot x-ray diagnostics in an XFEL

    CERN Document Server

    Sanchez-Gonzalez, A; Olivier, C; Barillot, T R; Ilchen, M; Lutman, A A; Marinelli, A; Maxwell, T; Achner, A; Agåker, M; Berrah, N; Bostedt, C; Buck, J; Bucksbaum, P H; Montero, S Carron; Cooper, B; Cryan, J P; Dong, M; Feifel, R; Frasinski, L J; Fukuzawa, H; Galler, A; Hartmann, G; Hartmann, N; Helml, W; Johnson, A S; Knie, A; Lindahl, A O; Liu, J; Motomura, K; Mucke, M; O'Grady, C; Rubensson, J-E; Simpson, E R; Squibb, R J; Såthe, C; Ueda, K; Vacher, M; Walke, D J; Zhaunerchyk, V; Coffee, R N; Marangos, J P

    2016-01-01

    X-ray free-electron lasers (XFELs) are the only sources currently able to produce bright few-fs pulses with tunable photon energies from 100 eV to more than 10 keV. Due to the stochastic SASE operating principles and other technical issues the output pulses are subject to large fluctuations, making it necessary to characterize the x-ray pulses on every shot for data sorting purposes. We present a technique that applies machine learning tools to predict x-ray pulse properties using simple electron beam and x-ray parameters as input. Using this technique at the Linac Coherent Light Source (LCLS), we report mean errors below 0.3 eV for the prediction of the photon energy at 530 eV and below 1.6 fs for the prediction of the delay between two x-ray pulses. We also demonstrate spectral shape prediction with a mean agreement of 97%. This approach could potentially be used at the next generation of high-repetition-rate XFELs to provide accurate knowledge of complex x-ray pulses at the full repetition rate.

  10. Atomic structure of machined semiconducting chips: An x-ray absorption spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Paesler, M.; Sayers, D.

    1988-12-01

    X-ray absorption spectroscopy (XAS) has been used to examine the atomic structure of chips of germanium that were produced by single point diamond machining. It is demonstrated that although the local (nearest neighbor) atomic structure is experimentally quite similar to that of single crystal specimens information from more distant atoms indicates the presence of considerable stress. An outline of the technique is given and the strength of XAS in studying the machining process is demonstrated.

  11. Tackling the x-ray cargo inspection challenge using machine learning

    Science.gov (United States)

    Jaccard, Nicolas; Rogers, Thomas W.; Morton, Edward J.; Griffin, Lewis D.

    2016-05-01

    The current infrastructure for non-intrusive inspection of cargo containers cannot accommodate exploding com-merce volumes and increasingly stringent regulations. There is a pressing need to develop methods to automate parts of the inspection workflow, enabling expert operators to focus on a manageable number of high-risk images. To tackle this challenge, we developed a modular framework for automated X-ray cargo image inspection. Employing state-of-the-art machine learning approaches, including deep learning, we demonstrate high performance for empty container verification and specific threat detection. This work constitutes a significant step towards the partial automation of X-ray cargo image inspection.

  12. Region-Based 4D Tomographic Image Reconstruction: Application to Cardiac X-ray CT

    NARCIS (Netherlands)

    G. Van Eyndhoven (Geert); K.J. Batenburg (Joost); J. Sijbers (Jan)

    2015-01-01

    htmlabstractX-ray computed tomography (CT) is a powerful tool for noninvasive cardiac imaging. However, radiation dose is a major issue. In this paper, we propose an iterative reconstruction method that reduces the radiation dose without compromising image quality. This is achieved by exploiting

  13. Multiwavelength classification of Galactic X-ray sources using machine-learning

    Science.gov (United States)

    Hare, Jeremy; Kargaltsev, Oleg; Rangelov, Blagoy; Pavlov, George G.; Posselt, Bettina; Volkov, Igor

    2018-01-01

    Observations with Chandra and XMM-Newton X-ray observatories have detected a large number of Galactic sources serendipitously. The X-ray properties of these sources are extracted and placed into catalogs where they remain largely unexplored. These rich datasets hold excellent potential for population studies of various types of astrophysical sources and may also hide rare source types, which we are yet to discover. However, X-ray data alone is often not enough to classify these sources and multiwavelength data must be used. We have developed a multiwavelength machine-learning pipeline (MUWCLASS), which uses a rich training dataset (of about 10,000 sources of known types) to classify X-ray sources. We describe the pipeline, training dataset, and verification and validation procedures used to build the pipeline. We then present and discuss the results of the classifications of X-ray sources, as well as the code's performance in multiple example environments, including dwarf galaxies, stellar clusters, SNRs, unidentified TeV sources, and a wide Galactic disk field.

  14. Machine recognition of navel orange worm damage in X-ray images of pistachio nuts

    Energy Technology Data Exchange (ETDEWEB)

    Keagy, P.M.; Schatzki, T.F. [USDA-ARS Western Regional Research Center, Albany, CA (United States); Parvin, B. [Lawrence Berkeley Lab., CA (United States)

    1994-11-01

    Insect infestation increases the probability of aflatoxin contamination in pistachio nuts. A non-destructive test is currently not available to determine the insect content of pistachio nuts. This paper presents the use of film X-ray images of various types of pistachio nuts to assess the possibility of machine recognition of insect infested nuts. Histogram parameters of four derived images are used in discriminant functions to select insect infested nuts from specific processing streams.

  15. Nondestructive Detection of the Internalquality of Apple Using X-Ray and Machine Vision

    Science.gov (United States)

    Yang, Fuzeng; Yang, Liangliang; Yang, Qing; Kang, Likui

    The internal quality of apple is impossible to be detected by eyes in the procedure of sorting, which could reduce the apple’s quality reaching market. This paper illustrates an instrument using X-ray and machine vision. The following steps were introduced to process the X-ray image in order to determine the mould core apple. Firstly, lifting wavelet transform was used to get a low frequency image and three high frequency images. Secondly, we enhanced the low frequency image through image’s histogram equalization. Then, the edge of each apple's image was detected using canny operator. Finally, a threshold was set to clarify mould core and normal apple according to the different length of the apple core’s diameter. The experimental results show that this method could on-line detect the mould core apple with less time consuming, less than 0.03 seconds per apple, and the accuracy could reach 92%.

  16. Anisotropic x-ray scattering and orientation fields in cardiac tissue cells

    Science.gov (United States)

    Bernhardt, M.; Nicolas, J.-D.; Eckermann, M.; Eltzner, B.; Rehfeldt, F.; Salditt, T.

    2017-01-01

    X-ray diffraction from biomolecular assemblies is a powerful technique which can provide structural information about complex architectures such as the locomotor systems underlying muscle contraction. However, in its conventional form, macromolecular diffraction averages over large ensembles. Progress in x-ray optics has now enabled to probe structures on sub-cellular scales, with the beam confined to a distinct organelle. Here, we use scanning small angle x-ray scattering (scanning SAXS) to probe the diffraction from cytoskeleton networks in cardiac tissue cells. In particular, we focus on actin-myosin composites, which we identify as the dominating contribution to the anisotropic diffraction patterns, by correlation with optical fluorescence microscopy. To this end, we use a principal component analysis approach to quantify direction, degree of orientation, nematic order, and the second moment of the scattering distribution in each scan point. We compare the fiber orientation from micrographs of fluorescently labeled actin fibers to the structure orientation of the x-ray dataset and thus correlate signals of two different measurements: the native electron density distribution of the local probing area versus specifically labeled constituents of the sample. Further, we develop a robust and automated fitting approach based on a power law expansion, in order to describe the local structure factor in each scan point over a broad range of the momentum transfer {q}{{r}}. Finally, we demonstrate how the methodology shown for freeze dried cells in the first part of the paper can be translated to alive cell recordings.

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... of knee x-rays. A portable x-ray machine is a compact apparatus that can be taken ... of the body being examined, an x-ray machine produces a small burst of radiation that passes ...

  18. Machine learning from hard x-ray surveys: applications to magnetic cataclysmic variable studies

    Science.gov (United States)

    Scaringi, Simone

    2009-11-01

    Within this thesis are discussed two main topics of contemporary astrophysics. The first is that of machine learning algorithms for astronomy whilst the second is that of magnetic cataclysmic variables (mCVs). To begin, an overview is given of ISINA: INTEGRAL Scouce Identifiction Network Algorithm. This machine learning algorithm, using random forests, is applied to the IBIS/ISGRI data set in order to ease the production of unbiased future soft gamma-ray source catalogues. The feature extraction process on an initial candidate list is described together with feature merging. Three trainng and testing sets are created in order to deal with the diverse time-scales encountered when dealing with the gamma-ray sky: one dealing with faint persistent source recognition, one dealing with strong persistent sources and a final one dealing with transients. For the latter, a new transient detection technique is introduced and described: the transient matrix. Finally the performance of the network is assessed and discussed using the testing set and some illustrative source examples. ISINA is also compared to the more conventional approach of visual inspection. Next mCVs are discussed, and in particular the properties arising from a hard X-ray selected sample which has proven remarkably efficient in detecting intermediate polars and asynchronous polars, two of the rarest type of cataclysmic variables (CVs). This thesis focuses particularly on the link between hard X-ray properties and spin/orbital periods. To this end, a new sample of these objects is constructed by cross-corelating candidate sources detected in INTEGRAL/IBIS observations against catalogues of known CVs. Also included in the analysis are hard X-ray Observations from Swift/BAT and SUZAKU/HXD in order to make the study more complete. It is found that most hard X-ray detected mCVs have Pspin/Porbattention is given to the very low number of detected systems in any ban between Pspin/Porb = 0.3 and Pspin/Porb = 1 and

  19. Evaluation of a robotic arm for echocardiography to X-ray image registration during cardiac catheterization procedures.

    Science.gov (United States)

    Ma, Yingliang; Penney, Graeme P; Bos, Dennis; Frissen, Peter; de Fockert, George; King, Andy; Gao, Gang; Yao, Cheng; Totman, John; Ginks, Matthew; Rinaldi, C; Razavi, Reza; Rhode, Kawal S

    2009-01-01

    We present an initial evaluation of a robotic arm for positioning a 3D echo probe during cardiac catheterization procedures. By tracking the robotic arm, X-ray table and X-ray C-arm, we are able to register the 3D echo images with live 2D X-ray images. In addition, we can also use tracking data from the robotic arm combined with system calibrations to create extended field of view 3D echo images. Both these features can be used for roadmapping to guide cardiac catheterization procedures. We have carried out a validation experiment of our registration method using a cross-wire phantom. Results show our method to be accurate to 3.5 mm. We have successfully demonstrated the creation of the extended field of view data on 2 healthy volunteers and the registration of echo and X-ray data on 1 patient undergoing a pacing study.

  20. COMP report: CPQR technical quality control guidelines for kilovoltage X ray radiotherapy machines.

    Science.gov (United States)

    Furstoss, Christophe

    2017-11-22

    The Canadian Organization of Medical Physicists (COMP) in close partnership with the Canadian Partnership for Quality Radiotherapy (CPQR) has developed a series of Technical Quality Control (TQC) guidelines for radiation treatment equipment. These guidelines outline the performance objectives that equipment should meet in order to ensure an acceptable level of radiation treatment quality. The TQC guidelines have been rigorously reviewed and field tested at various Canadian radiation treatment facilities. The development process enables rapid review and update to keep the guidelines current with changes in technology (the most updated version of this guideline can be found on the CPQR website). This particular TQC details recommended quality control for kilovoltage X Ray radiotherapy machines. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  1. Localization of cardiac volume and patient features in inverse geometry x-ray fluoroscopy

    Science.gov (United States)

    Speidel, Michael A.; Slagowski, Jordan M.; Dunkerley, David A. P.; Wagner, Martin; Funk, Tobias; Raval, Amish N.

    2017-03-01

    The scanning-beam digital x-ray (SBDX) system is an inverse geometry x-ray fluoroscopy technology that performs real-time tomosynthesis at planes perpendicular to the source-detector axis. The live display is a composite image which portrays sharp features (e.g. coronary arteries) extracted from a 16 cm thick reconstruction volume. We present a method for automatically determining the position of the cardiac volume prior to acquisition of a coronary angiogram. In the algorithm, a single non-contrast frame is reconstructed over a 44 cm thickness using shift-and-add digital tomosynthesis. Gradient filtering is applied to each plane to emphasize features such as the cardiomediastinal contour, diaphragm, and lung texture, and then sharpness vs. plane position curves are generated. Three sharpness metrics were investigated: average gradient in the bright field, maximum gradient, and the number of normalized gradients exceeding 0.5. A model correlating the peak sharpness in a non-contrast frame and the midplane of the coronary arteries in a contrast-enhanced frame was established using 37 SBDX angiographic loops (64-136 kg human subjects, 0-30° cranial- caudal). The average gradient in the bright field (primarily lung) and the number of normalized gradients >0.5 each yielded peaks correlated to the coronary midplane. The rms deviation between the predicted and true midplane was 1.57 cm. For a 16 cm reconstruction volume and the 5.5-11.5 cm thick cardiac volumes in this study, midplane estimation errors of 2.25-5.25 cm were tolerable. Tomosynthesis-based localization of cardiac volume is feasible. This technique could be applied prior to coronary angiography, or to assist in isocentering the patient for rotational angiography.

  2. Hybrid echo and x-ray image guidance for cardiac catheterization procedures by using a robotic arm: a feasibility study.

    Science.gov (United States)

    Ma, YingLiang; Penney, Graeme P; Bos, Dennis; Frissen, Peter; Rinaldi, C Aldo; Razavi, Reza; Rhode, Kawal S

    2010-07-07

    We present a feasibility study on hybrid echocardiography (echo) and x-ray image guidance for cardiac catheterization procedures. A self-tracked, remotely operated robotic arm with haptic feedback was developed that attached to a standard x-ray table. This was used to safely manipulate a three-dimensional (3D) trans-thoracic echo probe during simultaneous x-ray fluoroscopy and echo acquisitions. By a combination of calibration and tracking of the echo and x-ray systems, it was possible to register the 3D echo images with the 2D x-ray images. Visualization of the combined data was achieved by either overlaying triangulated surfaces extracted from segmented echo data onto the x-ray images or by overlaying volume rendered 3D echo data. Furthermore, in order to overcome the limited field of view of the echo probe, it was possible to create extended field of view (EFOV) 3D echo images by co-registering multiple tracked echo data to generate larger roadmaps for procedure guidance. The registration method was validated using a cross-wire phantom and showed a 2D target registration error of 3.5 mm. The clinical feasibility of the method was demonstrated during two clinical cases for patients undergoing cardiac pacing studies. The EFOV technique was demonstrated using two healthy volunteers.

  3. Hybrid echo and x-ray image guidance for cardiac catheterization procedures by using a robotic arm: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Ma Yingliang; Penney, Graeme P; Razavi, Reza; Rhode, Kawal S [Division of Imaging Sciences, King' s College, London SE1 7EH (United Kingdom); Bos, Dennis; Frissen, Peter [Philips Applied Technologies, High Tech. Campus 7, 5656 AE Eindhoven (Netherlands); Rinaldi, C Aldo, E-mail: y.ma@kcl.ac.u [Department of Cardiology, Guy' s and St Thomas' NHS Foundation Trust, London SE1 7EH (United Kingdom)

    2010-07-07

    We present a feasibility study on hybrid echocardiography (echo) and x-ray image guidance for cardiac catheterization procedures. A self-tracked, remotely operated robotic arm with haptic feedback was developed that attached to a standard x-ray table. This was used to safely manipulate a three-dimensional (3D) trans-thoracic echo probe during simultaneous x-ray fluoroscopy and echo acquisitions. By a combination of calibration and tracking of the echo and x-ray systems, it was possible to register the 3D echo images with the 2D x-ray images. Visualization of the combined data was achieved by either overlaying triangulated surfaces extracted from segmented echo data onto the x-ray images or by overlaying volume rendered 3D echo data. Furthermore, in order to overcome the limited field of view of the echo probe, it was possible to create extended field of view (EFOV) 3D echo images by co-registering multiple tracked echo data to generate larger roadmaps for procedure guidance. The registration method was validated using a cross-wire phantom and showed a 2D target registration error of 3.5 mm. The clinical feasibility of the method was demonstrated during two clinical cases for patients undergoing cardiac pacing studies. The EFOV technique was demonstrated using two healthy volunteers. (note)

  4. Three-dimensional tracking of cardiac catheters using an inverse geometry x-ray fluoroscopy system

    Energy Technology Data Exchange (ETDEWEB)

    Speidel, Michael A.; Tomkowiak, Michael T.; Raval, Amish N.; Van Lysel, Michael S. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States); Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States); Department of Medicine and Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53792 (United States)

    2010-12-15

    Purpose: Scanning beam digital x-ray (SBDX) is an inverse geometry fluoroscopic system with high dose efficiency and the ability to perform continuous real-time tomosynthesis at multiple planes. This study describes a tomosynthesis-based method for 3D tracking of high-contrast objects and present the first experimental investigation of cardiac catheter tracking using a prototype SBDX system. Methods: The 3D tracking algorithm utilizes the stack of regularly spaced tomosynthetic planes that are generated by SBDX after each frame period (15 frames/s). Gradient-filtered versions of the image planes are generated, the filtered images are segmented into object regions, and then a 3D coordinate is calculated for each object region. Two phantom studies of tracking performance were conducted. In the first study, an ablation catheter in a chest phantom was imaged as it was pulled along a 3D trajectory defined by a catheter sheath (10, 25, and 50 mm/s pullback speeds). SBDX tip tracking coordinates were compared to the 3D trajectory of the sheath as determined from a CT scan of the phantom after the registration of the SBDX and CT coordinate systems. In the second study, frame-to-frame tracking precision was measured for six different catheter configurations as a function of image noise level (662-7625 photons/mm{sup 2} mean detected x-ray fluence at isocenter). Results: During catheter pullbacks, the 3D distance between the tracked catheter tip and the sheath centerline was 1.0{+-}0.8 mm (mean {+-}one standard deviation). The electrode to centerline distances were comparable to the diameter of the catheter tip (2.3 mm), the confining sheath (4 mm outside diameter), and the estimated SBDX-to-CT registration error ({+-}0.7 mm). The tip position was localized for all 332 image frames analyzed and 83% of tracked positions were inside the 3D sheath volume derived from CT. The pullback speeds derived from the catheter trajectories were within 5% of the programed pullback speeds

  5. Retrieving the Quantitative Chemical Information at Nanoscale from Scanning Electron Microscope Energy Dispersive X-ray Measurements by Machine Learning

    Science.gov (United States)

    Jany, B. R.; Janas, A.; Krok, F.

    2017-11-01

    The quantitative composition of metal alloy nanowires on InSb(001) semiconductor surface and gold nanostructures on germanium surface is determined by blind source separation (BSS) machine learning (ML) method using non negative matrix factorization (NMF) from energy dispersive X-ray spectroscopy (EDX) spectrum image maps measured in a scanning electron microscope (SEM). The BSS method blindly decomposes the collected EDX spectrum image into three source components, which correspond directly to the X-ray signals coming from the supported metal nanostructures, bulk semiconductor signal and carbon background. The recovered quantitative composition is validated by detailed Monte Carlo simulations and is confirmed by separate cross-sectional TEM EDX measurements of the nanostructures. This shows that SEM EDX measurements together with machine learning blind source separation processing could be successfully used for the nanostructures quantitative chemical composition determination.

  6. Automation of the Franck-Hertz experiment and the Tel-X-Ometer x-ray machine using LABVIEW

    Science.gov (United States)

    Fedak, W.; Bord, D.; Smith, C.; Gawrych, D.; Lindeman, K.

    2003-05-01

    We describe the use of LABVIEW to automate data collection and instrument control for the Franck-Hertz experiment and for the popular Tel-X-Ometer x-ray machine. Such automation permits the rapid collection and reduction of large amounts of data, thus facilitating exploration of the basic physics of these experiments. The use of industry-standard software packages, such as ORIGIN and MATHEMATICA, provides students with valuable exposure to professional tools for the display and analysis of data.

  7. submitter The X-ray machine for the examination of quantum mechanics

    CERN Document Server

    Curceanu, Catalina; Bassi, Angelo; Bazzi, Massimiliano; Bertolucci, Sergio; Berucci, Carolina; Bragadireanu, Alexandru Mario; Cargnelli, Michael; Clozza, Alberto; De Paolis, Luca; Di Matteo, Sergio; Donadi, Sandro; D'uffizi, Alessandro; Egger, Jean-Pierre; Guaraldo, Carlo; Iliescu, Mihail; Laubenstein, Matthias; Marton, Johann; Milotti, Edoardo; Pichler, Andreas; Pietreanu, Dorel; Piscicchia, Kristian; Ponta, Titus; Scordo, Alessandro; Shi, Hexi; Sirghi, Diana; Sirghi, Florin; Sperandio, Laura; Doce, Oton Vazquez; Zmeskal, Johann

    2016-01-01

    By performing X-rays measurements in the underground laboratory of Gran Sasso, LNGS-INFN, we test a basic principle of quantum mechanics: the Pauli exclusion principle (PEP). In the future, we aim to use a similar experimental technique to search for X-rays as a signature of the spontaneous collapse of the wave function predicted by continuous spontaneous localization theories. We present the achieved results of the VIP experiment and the future plans to gain two orders of magnitude in testing PEP with the recently VIP2 setup installed at Gran Sasso.

  8. X-ray residual stress analysis on machined and tempered HPSN-ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Immelmann, S.; Welle, E.; Reimers, W. [Hahn-Meitner-Institut Berlin GmbH (Germany)

    1997-11-15

    The residual stress state induced by grinding and tempering of hot pressed silicon nitride (HPSN) samples is studied by X-ray diffraction. The results reveal that the residual stress values at the surface of the samples as well as their gradient within the penetration depth of the X-rays depend on the sintering aid and thus, on the glassy phase content of the HPSN. Tempering of the ground HPSN reduces the residual stress values due to microplastic deformation, whereas an oxidation of the glassy phase leads to the formation of compressive residual stresses. (orig.) 35 refs.

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... wrist, arm, elbow, shoulder, spine, pelvis, hip, thigh, knee, leg (shin), ankle or foot. top of page ... the patient standing upright, as in cases of knee x-rays. A portable x-ray machine is ...

  10. Fast frame rate rodent cardiac x-ray imaging using scintillator lens coupled to CMOS camera

    Science.gov (United States)

    Swathi Lakshmi, B.; Sai Varsha, M. K. N.; Kumar, N. Ashwin; Dixit, Madhulika; Krishnamurthi, Ganapathy

    2017-03-01

    Micro-Computed Tomography (MCT) systems for small animal imaging plays a critical role for monitoring disease progression and therapy evaluation. In this work, an in-house built micro-CT system equipped with a X-ray scintillator lens coupled to a commercial CMOS camera was used to test the feasibility of its application to Digital Subtraction Angiography (DSA). Literature has reported such studies being done with clinical X-ray tubes that can be pulsed rapidly or with rotating gantry systems, thus increasing the cost and infrastructural requirements.The feasibility of DSA was evaluated by injected Iodinated contrast agent (ICA) through the tail vein of a mouse. Projection images of the heart were acquired pre and post contrast using the high frame rate X-ray detector and processing done to visualize transit of ICA through the heart.

  11. Estimating photometric redshifts for X-ray sources in the X-ATLAS field using machine-learning techniques

    Science.gov (United States)

    Mountrichas, G.; Corral, A.; Masoura, V. A.; Georgantopoulos, I.; Ruiz, A.; Georgakakis, A.; Carrera, F. J.; Fotopoulou, S.

    2017-12-01

    We present photometric redshifts for 1031 X-ray sources in the X-ATLAS field using the machine-learning technique TPZ. X-ATLAS covers 7.1 deg2 observed with XMM-Newton within the Science Demonstration Phase of the H-ATLAS field, making it one of the largest contiguous areas of the sky with both XMM-Newton and Herschel coverage. All of the sources have available SDSS photometry, while 810 additionally have mid-IR and/or near-IR photometry. A spectroscopic sample of 5157 sources primarily in the XMM/XXL field, but also from several X-ray surveys and the SDSS DR13 redshift catalogue, was used to train the algorithm. Our analysis reveals that the algorithm performs best when the sources are split, based on their optical morphology, into point-like and extended sources. Optical photometry alone is not enough to estimate accurate photometric redshifts, but the results greatly improve when at least mid-IR photometry is added in the training process. In particular, our measurements show that the estimated photometric redshifts for the X-ray sources of the training sample have a normalized absolute median deviation, nmad ≈ 0.06, and a percentage of outliers, η = 10-14%, depending upon whether the sources are extended or point like. Our final catalogue contains photometric redshifts for 933 out of the 1031 X-ray sources with a median redshift of 0.9. The table of the photometric redshifts is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/608/A39

  12. 1-to 10-keV x-ray backlighting of annular wire arrays on the Sandia Z-machine using bent-crystal imaging techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Rambo, Patrick K.; Wenger, David Franklin; Bennett, Guy R.; Sinars, Daniel Brian; Smith, Ian Craig; Porter, John Larry, Jr.; Cuneo, Michael Edward; Rovang, Dean Curtis; Anderson, Jessica E.

    2003-07-01

    Annular wire array implosions on the Sandia Z-machine can produce >200 TW and 1-2 MJ of soft x rays in the 0.1-10 keV range. The x-ray flux and debris in this environment present significant challenges for radiographic diagnostics. X-ray backlighting diagnostics at 1865 and 6181 eV using spherically-bent crystals have been fielded on the Z-machine, each with a {approx}0.6 eVspectral bandpass, 10 {micro}m spatial resolution, and a 4 mm by 20mm field of view. The Z-Beamlet laser, a 2-TW, 2-kJ Nd:glass laser({lambda} = 527 nm), is used to produce 0.1-1 J x-ray sources for radiography. The design, calibration, and performance of these diagnostics is presented.

  13. Influence of x-ray pulse parameters on the image quality for moving objects in digital cardiac imaging.

    Science.gov (United States)

    Guibelalde, Eduardo; Vano, Eliseo; Vaquero, Francisco; González, Luciano

    2004-10-01

    The image quality of a single frame in a modern cardiac imaging x-ray facility can be improved by adjusting the automatic pulse exposure parameters. The effects of acquisition rate on patient dose and the detectability of moving objects have been fully described in scientific literature. However, the influence of automatic pulse exposure parameters is still to be determined. Images of a moving wheel (with lead wires) were acquired using an H5000 Philips Integris cardiac x-ray system. Poly(methylmethacrylate) plastic samples 20 and 30 cm thick were employed as the build-up phantom to simulate a patient. The images were obtained using preset clinical parameters for cardiac imaging procedures. The signal detectability and motion blur of a contrast bar at a transversal speed in the range of 100-150 mm/s were evaluated with a cine pulse width of 3, 5, 7, and 10 ms under automatic mA kV regulation. Two levels of exposure at the image intensifier entrance were included in this study. Signal detectability was analyzed in terms of the signal-to-noise ratio (SNR) and the value of SNR2/entrance surface dose. The blurring was modeled as a Gaussian-shaped blurring function, and the motion blur was expressed in terms of the peak full width at half maximum and amplitude (apparent contrast) of the resolution functions. A contrast bar simulating a vessel in motion at the maximum velocities of typical cardiac structures was exposed. Severe loss of image quality occurred at pulse widths > or =7 ms. It is also shown that below 5 ms static nonlinearities, likely caused by the need to use a large focus for cine acquisition, dominate the blurring process.

  14. Dose inspection and risk assessment on radiation safety for the use of non-medical X-ray machines in Taiwan

    Science.gov (United States)

    Hsu, Fang-Yuh; Hsu, Shih-Ming; Chao, Jiunn-Hsing

    2017-11-01

    The subject of this study is the on-site visits and inspections of facilities commissioned by the Atomic Energy Council (AEC) in Taiwan. This research was conducted to evaluate the possible dose and dose rate of cabinet-type X-ray equipment with nominal voltages of 30-150 kV and open-beam (portable or handheld) equipment, taking both normal operation and possibly abnormal operation conditions into account. Doses and dose rates were measured using a plastic scintillation survey meter and an electronic personal dosimeter. In total, 401 X-ray machines were inspected, including 139 units with nominal voltages of 30-50 kV X-ray equipment, 140 units with nominal voltages of 50-150 kV, and 122 open-beam (portable or handheld) X-ray equipment. The investigated doses for radiation workers and non-radiation workers operating cabinet-type X-ray equipment under normal safety conditions were all at the background dose level. Several investigated dose rates at the position of 10 cm away from the surface of open-beam (portable or handheld) X-ray equipment were very high, such X-ray machines are used by aeronautical police for the detection of suspected explosives, radiation workers are far away (at least 10 m away) from the X-ray machine during its operation. The doses per operation in X-ray equipment with a 30-50 kV nominal voltage were less than 1 mSv in all cases of abnormal use. Some doses were higher than 1 mSv per operation for X-ray equipment of 50-150 kV nominal voltage X-ray. The maximum dose rates at the beam exit have a very wide range, mostly less than 100 μSv/s and the largest value is about 3.92 mSv/s for open-beam (portable or handheld) X-ray devices. The risk induced by operating X-ray devices with nominal voltages of 30-50 kV is extremely low. The 11.5 mSv dose due to one operation at nominal voltage of 50-150 kV X-ray device is equivalent to the exposure of taking 575 chest X-rays. In the abnormal use of open-beam (portable or handheld) X-ray equipment, the

  15. OPTIMISATION OF NEON SXR (SOFT X-RAY YIELD OF THE INTI PLASMA FOCUS MACHINE AT 12 kV

    Directory of Open Access Journals (Sweden)

    A.R.J.A. FEDERICO

    2015-02-01

    Full Text Available The INTI plasma focus machine is a 3 kJ Mather type plasma focus machine,powered by a single Maxwell capacitor. The system produces remarkable consistent focusing action in neon, making it a suitable source for the production of high energy photons, electrons, ions and neon soft x-rays (SXR [1, 2]. The aim of this paper is to optimise the neon SXR yield of the INTI plasma focus machine operated at 12 kV by parametrically, changing the anode dimensions (radius and length using the Lee Model Code (version RADPFV5.15dd. Results of the optimisation procedures resulted in a neon SXR yield of 6.47 J at 2.5 torr and 12 kV, with a shorter length and a fatter anode radius of 7.9 cm and 1.2 cm respectively. This gives an improvement in the neon SXR yield of 40% when compares to neon SXR yield of 2.74 J at 2.5 torr 12 kV with the present configurations.

  16. NOTE: Hybrid echo and x-ray image guidance for cardiac catheterization procedures by using a robotic arm: a feasibility study

    Science.gov (United States)

    Ma, YingLiang; Penney, Graeme P.; Bos, Dennis; Frissen, Peter; Aldo Rinaldi, C.; Razavi, Reza; Rhode, Kawal S.

    2010-07-01

    We present a feasibility study on hybrid echocardiography (echo) and x-ray image guidance for cardiac catheterization procedures. A self-tracked, remotely operated robotic arm with haptic feedback was developed that attached to a standard x-ray table. This was used to safely manipulate a three-dimensional (3D) trans-thoracic echo probe during simultaneous x-ray fluoroscopy and echo acquisitions. By a combination of calibration and tracking of the echo and x-ray systems, it was possible to register the 3D echo images with the 2D x-ray images. Visualization of the combined data was achieved by either overlaying triangulated surfaces extracted from segmented echo data onto the x-ray images or by overlaying volume rendered 3D echo data. Furthermore, in order to overcome the limited field of view of the echo probe, it was possible to create extended field of view (EFOV) 3D echo images by co-registering multiple tracked echo data to generate larger roadmaps for procedure guidance. The registration method was validated using a cross-wire phantom and showed a 2D target registration error of 3.5 mm. The clinical feasibility of the method was demonstrated during two clinical cases for patients undergoing cardiac pacing studies. The EFOV technique was demonstrated using two healthy volunteers.

  17. Respiratory motion compensated overlay of surface models from cardiac MR on interventional x-ray fluoroscopy for guidance of cardiac resynchronization therapy procedures

    Science.gov (United States)

    Manzke, R.; Bornstedt, A.; Lutz, A.; Schenderlein, M.; Hombach, V.; Binner, L.; Rasche, V.

    2010-02-01

    Various multi-center trials have shown that cardiac resynchronization therapy (CRT) is an effective procedure for patients with end-stage drug invariable heart failure (HF). Despite the encouraging results of CRT, at least 30% of patients do not respond to the treatment. Detailed knowledge of the cardiac anatomy (coronary venous tree, left ventricle), functional parameters (i.e. ventricular synchronicity) is supposed to improve CRT patient selection and interventional lead placement for reduction of the number of non-responders. As a pre-interventional imaging modality, cardiac magnetic resonance (CMR) imaging has the potential to provide all relevant information. With functional information from CMR optimal implantation target sites may be better identified. Pre-operative CMR could also help to determine whether useful vein target segments are available for lead placement. Fused with X-ray, the mainstay interventional modality, improved interventional guidance for lead-placement could further help to increase procedure outcome. In this contribution, we present novel and practicable methods for a) pre-operative functional and anatomical imaging of relevant cardiac structures to CRT using CMR, b) 2D-3D registration of CMR anatomy and functional meshes with X-ray vein angiograms and c) real-time capable breathing motion compensation for improved fluoroscopy mesh overlay during the intervention based on right ventricular pacer lead tracking. With these methods, enhanced interventional guidance for left ventricular lead placement is provided.

  18. False dyssynchrony: problem with image-based cardiac functional analysis using x-ray computed tomography

    Science.gov (United States)

    Kidoh, Masafumi; Shen, Zeyang; Suzuki, Yuki; Ciuffo, Luisa; Ashikaga, Hiroshi; Fung, George S. K.; Otake, Yoshito; Zimmerman, Stefan L.; Lima, Joao A. C.; Higuchi, Takahiro; Lee, Okkyun; Sato, Yoshinobu; Becker, Lewis C.; Fishman, Elliot K.; Taguchi, Katsuyuki

    2017-03-01

    We have developed a digitally synthesized patient which we call "Zach" (Zero millisecond Adjustable Clinical Heart) phantom, which allows for an access to the ground truth and assessment of image-based cardiac functional analysis (CFA) using CT images with clinically realistic settings. The study using Zach phantom revealed a major problem with image-based CFA: "False dyssynchrony." Even though the true motion of wall segments is in synchrony, it may appear to be dyssynchrony with the reconstructed cardiac CT images. It is attributed to how cardiac images are reconstructed and how wall locations are updated over cardiac phases. The presence and the degree of false dyssynchrony may vary from scan-to-scan, which could degrade the accuracy and the repeatability (or precision) of image-based CT-CFA exams.

  19. Interventional guidance for cardiac resynchronization therapies: merging anatomic X-ray imaging with functional ultrasound imaging based on mutually-shared landmarks

    Energy Technology Data Exchange (ETDEWEB)

    Manzke, R.; Shechter, G.; Gutierrez, L.; Chan, R.C. [Philips Research North America, Briarcliff Manor, NY (United States); Tournoux, F.; Singh, J.; Picard, M. [Dept. of Cardiology, Massachusetts General Hospital, Harvard Medical School (United States); Brink, B. v.d.; Boomen, R. v.d. [Philips Medical System, Best (Netherlands); Gerard, O. [Philips Medical Systems, Paris (France)

    2007-06-15

    Detailed knowledge of cardiac anatomy and function is required for complex cardiac electrophysiology interventions. Cardiac resynchronization therapies (CRT), for example, requires information about coronary venous anatomy for left ventricular lead placement. In CRT, heart failure patients are equipped with dual-chamber pacemakers in order to improve cardiac output and heart failure symptoms. Cardiac function is mainly assessed with Ultrasound imaging. Fusion of complementary information from X-ray and ultrasound is an essential step towards fully utilizing all available information for CRT guidance. We present an approach for fusion of anatomical information (coronary vein structure) from X-ray with functional information (left ventricular deformation and dynamics) from ultrasound. We propose an image-based fusion approach based on mutually-shared landmarks which enable registration of both imaging spaces without the need for external tracking. (orig.)

  20. Efficient feature-based 2D/3D registration of transesophageal echocardiography to x-ray fluoroscopy for cardiac interventions

    Science.gov (United States)

    Hatt, Charles R.; Speidel, Michael A.; Raval, Amish N.

    2014-03-01

    We present a novel 2D/ 3D registration algorithm for fusion between transesophageal echocardiography (TEE) and X-ray fluoroscopy (XRF). The TEE probe is modeled as a subset of 3D gradient and intensity point features, which facilitates efficient 3D-to-2D perspective projection. A novel cost-function, based on a combination of intensity and edge features, evaluates the registration cost value without the need for time-consuming generation of digitally reconstructed radiographs (DRRs). Validation experiments were performed with simulations and phantom data. For simulations, in silica XRF images of a TEE probe were generated in a number of different pose configurations using a previously acquired CT image. Random misregistrations were applied and our method was used to recover the TEE probe pose and compare the result to the ground truth. Phantom experiments were performed by attaching fiducial markers externally to a TEE probe, imaging the probe with an interventional cardiac angiographic x-ray system, and comparing the pose estimated from the external markers to that estimated from the TEE probe using our algorithm. Simulations found a 3D target registration error of 1.08(1.92) mm for biplane (monoplane) geometries, while the phantom experiment found a 2D target registration error of 0.69mm. For phantom experiments, we demonstrated a monoplane tracking frame-rate of 1.38 fps. The proposed feature-based registration method is computationally efficient, resulting in near real-time, accurate image based registration between TEE and XRF.

  1. Mesoscale imaging with cryo-light and X-rays: Larger than molecular machines, smaller than a cell.

    Science.gov (United States)

    Ekman, Axel A; Chen, Jian-Hua; Guo, Jessica; McDermott, Gerry; Le Gros, Mark A; Larabell, Carolyn A

    2017-01-01

    In the context of cell biology, the term mesoscale describes length scales ranging from that of an individual cell, down to the size of the molecular machines. In this spatial regime, small building blocks self-organise to form large, functional structures. A comprehensive set of rules governing mesoscale self-organisation has not been established, making the prediction of many cell behaviours difficult, if not impossible. Our knowledge of mesoscale biology comes from experimental data, in particular, imaging. Here, we explore the application of soft X-ray tomography (SXT) to imaging the mesoscale, and describe the structural insights this technology can generate. We also discuss how SXT imaging is complemented by the addition of correlative fluorescence data measured from the same cell. This combination of two discrete imaging modalities produces a 3D view of the cell that blends high-resolution structural information with precise molecular localisation data. © 2016 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... x-ray machine is a compact apparatus that can be taken to the patient in a hospital ... so that any change in a known abnormality can be monitored over time. Follow-up examinations are ...

  3. Multicomponent signal unmixing from nanoheterostructures: overcoming the traditional challenges of nanoscale X-ray analysis via machine learning.

    Science.gov (United States)

    Rossouw, David; Burdet, Pierre; de la Peña, Francisco; Ducati, Caterina; Knappett, Benjamin R; Wheatley, Andrew E H; Midgley, Paul A

    2015-04-08

    The chemical composition of core-shell nanoparticle clusters have been determined through principal component analysis (PCA) and independent component analysis (ICA) of an energy-dispersive X-ray (EDX) spectrum image (SI) acquired in a scanning transmission electron microscope (STEM). The method blindly decomposes the SI into three components, which are found to accurately represent the isolated and unmixed X-ray signals originating from the supporting carbon film, the shell, and the bimetallic core. The composition of the latter is verified by and is in excellent agreement with the separate quantification of bare bimetallic seed nanoparticles.

  4. Joint x-ray

    Science.gov (United States)

    X-ray - joint; Arthrography; Arthrogram ... x-ray technologist will help you position the joint to be x-rayed on the table. Once in place, pictures are taken. The joint may be moved into other positions for more ...

  5. Technical Note: Impact on detective quantum efficiency of edge angle determination method by International Electrotechnical Commission methodology for cardiac x-ray image detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gislason-Lee, Amber J., E-mail: A.J.Gislason@leeds.ac.uk; Tunstall, Clare M.; Kengyelics, Stephen K.; Cowen, Arnold R.; Davies, Andrew G. [LXi Research, Division of Biomedical Imaging, University of Leeds, Worsley Building, Clarendon Way, Leeds LS2 9JT (United Kingdom)

    2015-08-15

    Purpose: Cardiac x-ray detectors are used to acquire moving images in real-time for angiography and interventional procedures. Detective quantum efficiency (DQE) is not generally measured on these dynamic detectors; the required “for processing” image data and control of x-ray settings have not been accessible. By 2016, USA hospital physicists will have the ability to measure DQE and will likely utilize the International Electrotechnical Commission (IEC) standard for measuring DQE of dynamic x-ray imaging devices. The current IEC standard requires an image of a tilted tungsten edge test object to obtain modulation transfer function (MTF) for DQE calculation. It specifies the range of edge angles to use; however, it does not specify a preferred method to determine this angle for image analysis. The study aimed to answer the question “will my choice in method impact my results?” Four different established edge angle determination methods were compared to investigate the impact on DQE. Methods: Following the IEC standard, edge and flat field images were acquired on a cardiac flat-panel detector to calculate MTF and noise power spectrum, respectively, to determine DQE. Accuracy of the methods in determining the correct angle was ascertained using a simulated edge image with known angulations. Precision of the methods was ascertained using variability of MTF and DQE, calculated via bootstrapping. Results: Three methods provided near equal angles and the same MTF while the fourth, with an angular difference of 6%, had a MTF lower by 3% at 1.5 mm{sup −1} spatial frequency and 8% at 2.5 mm{sup −1}; corresponding DQE differences were 6% at 1.5 mm{sup −1} and 17% at 2.5 mm{sup −1}; differences were greater than standard deviations in the measurements. Conclusions: DQE measurements may vary by a significant amount, depending on the method used to determine the edge angle when following the IEC standard methodology for a cardiac x-ray detector. The most

  6. Nanometer x-ray lithography

    Science.gov (United States)

    Hartley, Frank T.; Khan Malek, Chantal G.

    1999-10-01

    New developments for x-ray nanomachining include pattern transfer onto non-planar surfaces coated with electrodeposited resists using synchrotron radiation x-rays through extremely high-resolution mask made by chemically assisted focused ion beam lithography. Standard UV photolithographic processes cannot maintain sub-micron definitions over large variation in feature topography. The ability of x-ray printing to pattern thin or thick layers of photoresist with high resolution on non-planar surfaces of large and complex topographies with limited diffraction and scattering effects and no substrate reflection is known and can be exploited for patterning microsystems with non-planar 3D geometries as well as multisided and multilayered substrates. Thin conformal coatings of electro-deposited positive and negative tone photoresist have been shown to be x-ray sensitive and accommodate sub-micro pattern transfer over surface of extreme topographical variations. Chemically assisted focused ion beam selective anisotropic erosion was used to fabricate x-ray masks directly. Masks with feature sizes less than 20 nm through 7 microns of gold were made on bulk silicon substrates and x-ray mask membranes. The technique is also applicable to other high density materials. Such masks enable the primary and secondary patterning and/or 3D machining of Nano-Electro-Mechanical Systems over large depths or complex relief and the patterning of large surface areas with sub-optically dimensioned features.

  7. Patient radiation dose reduction using an X-ray imaging noise reduction technology for cardiac angiography and intervention.

    Science.gov (United States)

    Nakamura, Shigeru; Kobayashi, Tomoko; Funatsu, Atsushi; Okada, Tadahisa; Mauti, Maria; Waizumi, Yuki; Yamada, Shinichi

    2016-05-01

    Coronary angiography and intervention can expose patients to high radiation dose. This retrospective study quantifies the patient dose reduction due to the introduction of a novel X-ray imaging noise reduction technology using advanced real-time image noise reduction algorithms and optimized acquisition chain for fluoroscopy and exposure in interventional cardiology. Patient, procedure and radiation dose data were retrospectively collected in the period August 2012-August 2013 for 883 patients treated with the image noise reduction technology (referred as "new system"). The same data were collected for 1083 patients in the period April 2011-July 2012 with a system using state-of-the-art image processing and reference acquisition chain (referred as "reference system"). Procedures were divided into diagnostic (CAG) and intervention (PCI). Acquisition parameters such as fluoroscopy time, volume of contrast medium, number of exposure images and number of stored fluoroscopy images were collected to classify procedure complexity. The procedural dose reduction was investigated separately for three main cardiologists. The new system provides significant dose reduction compared to the reference system. Median DAP values decreased for all procedures (p X-ray imaging technology combining advanced real-time image noise reduction algorithms and anatomy-specific optimized fluoroscopy and cine acquisition chain provides 66 % patient dose reduction in interventional cardiology.

  8. A study on the dependence of exposure dose reduction and image evaluation on the distance from the dental periapical X-ray machine

    Science.gov (United States)

    Joo, Kyu-Ji; Shin, Jae-Woo; Dong, Kyung-Rae; Lim, Chang-Seon; Chung, Woon-Kwan; Kim, Young-Jae

    2013-11-01

    Reducing the exposure dose from a periapical X-ray machine is an important aim in dental radiography. Although the radiation exposure dose is generally low, any radiation exposure is harmful to the human body. Therefore, this study developed a method that reduces the exposure dose significantly compared to that encountered in a normal procedure, but still produces an image with a similar resolution. The correlation between the image resolution and the exposure dose of the proposed method was examined with increasing distance between the dosimeter and the X-ray tube. The results were compared with those obtained from the existing radiography method. When periapical radiography was performed once according to the recommendations of the International Commission on Radiological Protection (ICRP), the measured skin surface dose was low at 7 mGy or below. In contrast, the skin surface dose measured using the proposed method was only 1.57 mGy, showing a five-fold reduction. These results suggest that further decreases in dose might be achieved using the proposed method.

  9. Chest X-Ray

    Medline Plus

    Full Text Available ... the most commonly performed x-ray exams and use a very small dose of ionizing radiation to ... to your health. While a chest x-ray use a tiny dose of ionizing radiation, the benefit ...

  10. Cardiac Catheterization (For Teens)

    Science.gov (United States)

    ... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... will do the cardiac catheterization in a catheterization lab . The lab contains X-ray and imaging machines ...

  11. Hand x-ray

    Science.gov (United States)

    X-ray - hand ... A hand x-ray is taken in a hospital radiology department or your health care provider's office by an ... technician. You will be asked to place your hand on the x-ray table, and keep it ...

  12. X-Ray

    Science.gov (United States)

    ... show up on chest X-rays. Breast cancer. Mammography is a special type of X-ray test used to examine breast tissue. Enlarged heart. This sign of congestive heart failure shows up clearly on X-rays. Blocked blood vessels. Injecting a contrast material that contains iodine can help highlight sections ...

  13. Reduction in Radiation Dose in a Pediatric Cardiac Catheterization Lab Using the Philips AlluraClarity X-ray System.

    Science.gov (United States)

    Sullivan, Patrick M; Harrison, David; Badran, Sarah; Takao, Cheryl M; Ing, Frank F

    2017-08-02

    The objective of this study was to compare radiation doses and imaging quality using Philips AlluraClarity (Philips Healthcare, Best, The Netherlands) X-ray system and an older generation reference system. AlluraClarity is a new generation fluoroscopy system designed to reduce radiation without compromising image quality, but reports of its use in pediatric patients are limited. Dose area products (DAP, mGy cm(2)) and DAP/kg were compared in patients catheterized using Allura Xper and AlluraClarity systems over a year of use for each. Randomly selected studies from each system were assessed for image quality. The 430 patients imaged with Clarity were larger than the 332 imaged with Xper (median BSA: 0.74 vs. 0.64 m(2), p = 0.06), and median total fluoroscopic times (TFT) were similar (15.8 vs. 16.1 min, p = 0.37). Median DAPs were 8661 mGy cm(2) (IQR: 18,300 mGy cm(2)) and 4523 mGy cm(2) (IQR: 11,596 mGy cm(2)) with Xper and Clarity, respectively (p lab.

  14. X-Ray Polarimetry

    OpenAIRE

    Kaaret, Philip

    2014-01-01

    We review the basic principles of X-ray polarimetry and current detector technologies based on the photoelectric effect, Bragg reflection, and Compton scattering. Recent technological advances in high-spatial-resolution gas-filled X-ray detectors have enabled efficient polarimeters exploiting the photoelectric effect that hold great scientific promise for X-ray polarimetry in the 2-10 keV band. Advances in the fabrication of multilayer optics have made feasible the construction of broad-band ...

  15. Chest X-Ray

    Medline Plus

    Full Text Available ... by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, ... d like to talk with you about chest radiography also known as chest x-rays. Chest x- ...

  16. Chest X-Ray

    Medline Plus

    Full Text Available ... to consider the likelihood of benefit to your health. While a chest x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot ...

  17. X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fenster, A. [Univ. of Western Ontario, J.P. Robarts Institute, London, Ontario (Canada); Yaffe, M.J. [Univ. of Toronto, Depts. of Medical Biophysics and Medical Imaging, North York, Ontario (Canada)

    1995-09-01

    In this article, we briefly review the principles of x-ray imaging, consider some of its applications in medicine and describe some of the developments in this area which have taken place in Canada. X rays were first used for diagnosis and therapy in medicine almost immediately after the report of their discovery by Roentgen in 1895. X-ray imaging has remained the primary tool for the investigation of structures within the body up to the present time (Johns and Cunningham 1983). Medical x rays are produced in a vacuum tube by the electron bombardment of a metallic target. Electrons emitted from a heated cathode are accelerated through an electric field to energies of 20-150 keV (wavelength 6.2-0.83 nm) and strike a target anode. X rays appear in a spectrum of bremsstrahlung radiation with energies ranging from 0 to a value that is numerically equal to the peak voltage applied between the cathode and anode of the x-ray tube (Figure 1). In addition, where the energy of the impinging electrons exceeds the binding energy of inner atomic orbitals of the target material, electrons may be ejected from those shells. Filling of these shells by more loosely-bound electrons gives rise to x rays whose energies are equal to the difference of the binding energies of the donor and acceptor shells. The energies of these characteristic x rays are unique to the target material. Less than 1% of the energy of the incident electrons is converted to that of x rays, while the remainder is dissipated as heat in the target. For this reason, a tremendous amount of engineering has gone into the design of x-ray tubes that can yield a large fluence rate of quanta from a small effective source size, while withstanding the enormous applied heat loading (e.g. 10 kJ per exposure). Tungsten is by far the most common material used for targets in tubes for diagnostic radiology, because of its high melting point and its high atomic number; the efficiency of x-ray production is proportional to Z of the

  18. X-ray lasers

    CERN Document Server

    Elton, Raymond C

    2012-01-01

    The first in its field, this book is both an introduction to x-ray lasers and a how-to guide for specialists. It provides new entrants and others interested in the field with a comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. In one succinct volume, X-Ray Lasers collects the knowledge and experience gained in two decades of x-ray laser development and conveys the exciting challenges and possibilities still to come._Add on for longer version of blurb_M>The reader is first introduced

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive medical ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

  1. Abdomen X-Ray (Radiography)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Abdomen Abdominal x-ray uses a very small ... of an abdominal x-ray? What is abdominal x-ray? An x-ray (radiograph) is a noninvasive medical ...

  2. Chest X-Ray

    Medline Plus

    Full Text Available ... Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey ...

  3. Chest X-Ray

    Medline Plus

    Full Text Available ... Index A-Z Spotlight March is National Colorectal Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  4. Chest X-Ray

    Medline Plus

    Full Text Available ... Site Index A-Z Spotlight February is American Heart Month Recently posted: Carotid Intima-Media Thickness Test ... x-ray is used to evaluate the lungs, heart and chest wall and may be used to ...

  5. Chest X-Ray

    Medline Plus

    Full Text Available ... chest x-ray is used to evaluate the lungs, heart and chest wall and may be used ... diagnose and monitor treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A ...

  6. Chest X-Ray

    Medline Plus

    Full Text Available ... breath, persistent cough, fever, chest pain or injury. It may also be useful to help diagnose and ... have some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to ...

  7. Chest X-Ray

    Medline Plus

    Full Text Available ... accurate diagnosis far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot ... Inc. (RSNA). To help ensure current and accurate information, we do not permit copying but encourage linking ...

  8. Sinus x-ray

    Science.gov (United States)

    ... an infection and inflammation of the sinuses called sinusitis . A sinus x-ray is ordered when you have any of the following: Symptoms of sinusitis Other sinus disorders, such as a deviated septum ( ...

  9. Chest X-Ray

    Medline Plus

    Full Text Available ... Index A-Z Spotlight November is National Lung Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  10. Chest X-Ray

    Medline Plus

    Full Text Available ... exams and use a very small dose of ionizing radiation to produce pictures of the inside of the ... chest x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs ...

  11. Chest X-Ray

    Medline Plus

    Full Text Available ... and You Take our survey Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound Radiology and You ...

  12. X-ray

    Science.gov (United States)

    ... X-ray References Geleijns J, Tack D. Medical physics: radiation risks. In: Adam A, Dixon AK, Gillard ... Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic ...

  13. Chest X-Ray

    Medline Plus

    Full Text Available ... and use a very small dose of ionizing radiation to produce pictures of the inside of the ... x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs ...

  14. Chest X-Ray

    Medline Plus

    Full Text Available ... Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. ... University in Durham, North Carolina. I’d like to talk with you about chest radiography also known ...

  15. Chest X-Ray

    Medline Plus

    Full Text Available ... Index A-Z Spotlight October is National Breast Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ... of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...

  16. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... drawer under the table holds the x-ray film or image recording plate . Sometimes the x-ray ... extended over the patient while an x-ray film holder or image recording plate is placed beneath ...

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... ray examination. X-rays usually have no side effects in the typical diagnostic range for this exam. ... x-rays. A Word About Minimizing Radiation Exposure Special care is taken during x-ray examinations to ...

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... ray examination. X-rays usually have no side effects in the typical diagnostic range for this exam. ... Media Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to X-ray (Radiography) - ...

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... that might interfere with the x-ray images. Women should always inform their physician and x-ray ... Safety page for more information about radiation dose. Women should always inform their physician or x-ray ...

  2. X-Ray Absorption with Transmission X-Ray Microscopes

    NARCIS (Netherlands)

    de Groot, F.M.F.|info:eu-repo/dai/nl/08747610X

    2016-01-01

    In this section we focus on the use of transmission X-ray microscopy (TXM) to measure the XAS spectra. In the last decade a range of soft X-ray and hard X-ray TXM microscopes have been developed, allowing the measurement of XAS spectra with 10–100 nm resolution. In the hard X-ray range the TXM

  3. Subluminous X-ray binaries

    NARCIS (Netherlands)

    Armas Padilla, M.

    2013-01-01

    The discovery of the first X-ray binary, Scorpius X-1, by Giacconi et al. (1962), marked the birth of X-ray astronomy. Following that discovery, many additional X-ray sources where found with the first generation of X-ray rockets and observatories (e.g., UHURU and Einstein). The short-timescale

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) ... top of page What are some common uses of the procedure? A bone x-ray is used ...

  5. Lumbosacral spine x-ray

    Science.gov (United States)

    X-ray - lumbosacral spine; X-ray - lower spine ... be placed over the lower part of your spine. You will be asked to hold your breath ... x-ray. The most common reason for lumbosacral spine x-ray is to look for the cause ...

  6. Application of scanning electron microscopy and X-ray microanalysis: FE-SEM, ESEM-EDS, and EDS mapping for studying the characteristics of topographical microstructure and elemental mapping of human cardiac calcified deposition.

    Science.gov (United States)

    Chang, Hsiao-Huang; Cheng, Ching-Li; Huang, Pei-Jung; Lin, Shan-Yang

    2014-01-01

    To explore the pathogenic mineral formation in a huge cardiolith isolated from the left heart atrium of an 80-year-old male patient, field emission scanning electron microscopy (FE-SEM) was used to analyze the topographic microstructure and perform elemental mapping in a cross-section of the cardiac calcified deposit after dissection. Environmental SEM equipped with an energy dispersive X-ray spectrometer (EDS) was also used to investigate the composition and spatial distribution of elements in the cross-section, and fiberoptic Raman spectroscopy was used to reidentify the chemical composition of designated positions. The results indicated that calcium hydroxyapatite and cholesterol were the main components of the cardiac calculus. The plate-like structures of calcium hydroxyapatite were unevenly spread over the cholesterol of the cardiac calculus. The calcium hydroxyapatite-rich area exhibited higher amounts of C, O, P, and Ca elements as well as trace amounts of N, Na, Mg, and Al, whereas the major concentration of C, minor concentrations of N and O, and trace amounts of P and Ca were observed in the cholesterol-rich area. Hypercholesterolemia associated with calcification of this cardiac calculus was proposed. Both FE-SEM and ESEM energy dispersive X-ray microanalyses were performed directly, for the first time, to provide useful information on the microstructural characteristics and spatial distribution of elements on the surface of human cardiac calculi.

  7. Chest X-Ray

    Medline Plus

    Full Text Available ... of ionizing radiation, the benefit of an accurate diagnosis far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot org. Thank you for your time! Spotlight November is National Lung Cancer Awareness Month Recently posted: Carotid Intima-Media Thickness ...

  8. Chest X-Ray

    Medline Plus

    Full Text Available ... Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions ... Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey Rubin, ...

  9. Pelvis x-ray

    Science.gov (United States)

    The x-ray is used to look for: Fractures Tumors Degenerative conditions of bones in the hips, pelvis, and upper legs ... Abnormal results may suggest: Pelvic fractures Arthritis of the hip joint ... spondylitis (abnormal stiffness of the spine and joint) ...

  10. Chest X-Ray

    Medline Plus

    Full Text Available ... Radiology (IDoR) Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript ... Carotid Intima-Media Thickness Test Medical Imaging Costs Video: Abdominal Ultrasound Video: Pelvic Ultrasound November 8 is ...

  11. X-ray filter for x-ray powder diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Sinsheimer, John Jay; Conley, Raymond P.; Bouet, Nathalie C. D.; Dooryhee, Eric; Ghose, Sanjit

    2018-01-23

    Technologies are described for apparatus, methods and systems effective for filtering. The filters may comprise a first plate. The first plate may include an x-ray absorbing material and walls defining first slits. The first slits may include arc shaped openings through the first plate. The walls of the first plate may be configured to absorb at least some of first x-rays when the first x-rays are incident on the x-ray absorbing material, and to output second x-rays. The filters may comprise a second plate spaced from the first plate. The second plate may include the x-ray absorbing material and walls defining second slits. The second slits may include arc shaped openings through the second plate. The walls of the second plate may be configured to absorb at least some of second x-rays and to output third x-rays.

  12. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... and x-rays. A Word About Minimizing Radiation Exposure Special care is taken during x-ray examinations ... patient's body not being imaged receive minimal radiation exposure. top of page What are the limitations of ...

  13. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... foot. top of page What are some common uses of the procedure? A bone x-ray is ... care is taken during x-ray examinations to use the lowest radiation dose possible while producing the ...

  14. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... shades of gray and air appears black. Until recently, x-ray images were maintained on large film ... assist you in finding the most comfortable position possible that still ensures x-ray image quality. top ...

  15. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ... body. Once it is carefully aimed at the part of the body being examined, an x-ray ...

  16. Coherent x-ray optics

    CERN Document Server

    Paganin, David M

    2006-01-01

    'Coherent X-Ray Optics' gives a thorough treatment of the rapidly expanding field of coherent x-ray optics, which has recently experienced something of a renaissance with the availability of third-generation synchrotron sources.

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patient. top of page How does the procedure work? X-rays are a form of radiation like ... Safety page for more information about radiation dose. Women should always inform their physician or x-ray ...

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... tissues around or in bones. top of page How should I prepare? Most bone x-rays require ... is placed beneath the patient. top of page How does the procedure work? X-rays are a ...

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... fracture. guide orthopedic surgery, such as spine repair/fusion, joint replacement and fracture reductions. look for injury, ... and Media Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to X-ray ( ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ... and procedures may vary by geographic region. Discuss the fees associated with your prescribed ...

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures ...

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... pregnancy and x-rays. top of page What does the equipment look like? The equipment typically used ... placed beneath the patient. top of page How does the procedure work? X-rays are a form ...

  3. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest ... have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures ...

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... that might interfere with the x-ray images. Women should always inform their physician and x-ray technologist if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy ...

  5. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ...

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures ...

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... tissue shows up in shades of gray and air appears black. Until recently, x-ray images were ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ...

  8. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... of page What are some common uses of the procedure? A bone x-ray is used to: ... and x-rays. top of page What does the equipment look like? The equipment typically used for ...

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... be taken to minimize radiation exposure to the baby. See the Safety page for more information about pregnancy and x-rays. top of page What does the equipment look like? The equipment typically used for bone x-rays consists of an x-ray tube suspended over a table on which the patient ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... x-rays. top of page What does the equipment look like? The equipment typically used for bone x-rays consists of ... and joint abnormalities, such as arthritis. X-ray equipment is relatively inexpensive and widely available in emergency ...

  11. X-Ray Exam: Forearm

    Science.gov (United States)

    ... recorded on a computer or special X-ray film. This image shows the soft tissues and bones of the forearm. The X-ray image is black and white. Dense structures that block the passage of the X-ray beam through the body, such as the bones, appear white on the ...

  12. Jovian X-ray emissions

    Science.gov (United States)

    Waite, J. H.; Lewis, W. S.; Gladstone, G. R.; Fabian, A. C.; Brandt, W. N.

    1996-01-01

    The Einstein and Rosat observations of X-ray emissions from Jupiter are summarized. Jupiter's soft X-ray emission is observed to originate from the planet's auroral zones, and specifically, from its equatorial region. The processes responsible for these emissions are not established. The brightness distribution of the Jovian X-rays is characterized by the dependence on central meridian longitude and by north-south and morning-afternoon asymmetries. The X-rays observed during the impact of the comet Shoemaker-Levy 9 are believed to be impact-induced brightenings of the X-ray aurora.

  13. X-Ray Lasers 2016

    CERN Document Server

    Bulanov, Sergei; Daido, Hiroyuki; Kato, Yoshiaki

    2018-01-01

    These proceedings comprise a selection of invited and contributed papers presented at the 15th International Conference on X-Ray Lasers (ICXRL 2016), held at the Nara Kasugano International Forum, Japan, from May 22 to 27, 2016. This conference was part of an ongoing series dedicated to recent developments in the science and technology of x-ray lasers and other coherent x-ray sources with additional focus on supporting technologies, instrumentation and applications.   The book showcases recent advances in the generation of intense, coherent x-rays, the development of practical devices and their applications across a wide variety of fields. It also discusses emerging topics such as plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generations, as well as other x-ray generation schemes.

  14. X-ray instrumentation for SR beamlines

    CERN Document Server

    Kovalchuk, M V; Zheludeva, S I; Aleshko-Ozhevsky, O P; Arutynyan, E H; Kheiker, D M; Kreines, A Y; Lider, V V; Pashaev, E M; Shilina, N Y; Shishkov, V A

    2000-01-01

    The main possibilities and parameters of experimental X-ray stations are presented: 'Protein crystallography', 'X-ray structure analysis', 'High-precision X-ray optics', 'X-ray crystallography and material science', 'X-ray topography', 'Photoelectron X-ray standing wave' that are being installed at Kurchatov SR source by A.V. Shubnikov Institute of Crystallography.

  15. Soft X-ray optics

    CERN Document Server

    Spiller, Eberhard A

    1993-01-01

    This text describes optics mainly in the 10 to 500 angstrom wavelength region. These wavelengths are 50 to 100 times shorter than those for visible light and 50 to 100 times longer than the wavelengths of medical x rays or x-ray diffraction from natural crystals. There have been substantial advances during the last 20 years, which one can see as an extension of optical technology to shorter wavelengths or as an extension of x-ray diffraction to longer wavelengths. Artificial diffracting structures like zone plates and multilayer mirrors are replacing the natural crystals of x-ray diffraction.

  16. X-ray Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yano, Junko; Yachandra, Vittal K.

    2009-07-09

    This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of X-ray absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.

  17. Applicability of self-activation of an NaI scintillator for measurement of photo-neutrons around a high-energy X-ray radiotherapy machine.

    Science.gov (United States)

    Wakabayashi, Genichiro; Nohtomi, Akihiro; Yahiro, Eriko; Fujibuchi, Toshioh; Fukunaga, Junichi; Umezu, Yoshiyuki; Nakamura, Yasuhiko; Nakamura, Katsumasa; Hosono, Makoto; Itoh, Tetsuo

    2015-01-01

    The applicability of the activation of an NaI scintillator for neutron monitoring at a clinical linac was investigated experimentally. Thermal neutron fluence rates are derived by measurement of the I-128 activity generated in an NaI scintillator irradiated by neutrons; β-rays from I-128 are detected efficiently by the NaI scintillator. In order to verify the validity of this method for neutron measurement, we irradiated an NaI scintillator at a research reactor, and the neutron fluence rate was estimated. The method was then applied to neutron measurement at a 10-MV linac (Varian Clinac 21EX), and the neutron fluence rate was estimated at the isocenter and at 30 cm from the isocenter. When the scintillator was irradiated directly by high-energy X-rays, the production of I-126 was observed due to photo-nuclear reactions, in addition to the generation of I-128 and Na-24. From the results obtained by these measurements, it was found that the neutron measurement by activation of an NaI scintillator has a great advantage in estimates of a low neutron fluence rate by use of a quick measurement following a short-time irradiation. Also, the future application of this method to quasi real-time monitoring of neutrons during patient treatments at a radiotherapy facility is discussed, as well as the method of evaluation of the neutron dose.

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray and air ...

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... diagnosis and treatment. No radiation remains in a patient's body after an x-ray examination. X-rays usually have no side effects in the typical diagnostic range for this exam. Risks There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... dose possible while producing the best images for evaluation. National and international radiology protection organizations continually review and update the technique standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose ...

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... widely available in emergency rooms, physician offices, ambulatory care centers, nursing homes and other locations, making it convenient for both patients and physicians. Because x-ray imaging is fast and easy, it is ... Radiation Exposure Special care is taken during x-ray examinations to use ...

  2. Chandra's X-ray Vision

    Indian Academy of Sciences (India)

    1999-07-23

    Jul 23, 1999 ... GENERAL I ARTICLE. Chandra's X-ray Vision. K P Singh. Chandra X-ray Observatory (CXO) is a scientific satellite (moon/ chandra), named after the Indian-born Nobel laureate. Subrahmanyan Chandrasekhar - one of the foremost astro- physicists of the twentieth century and popularly known as. Chandra.

  3. X-Ray Exam: Ankle

    Science.gov (United States)

    ... radiation through the ankle, and black and white images of the bones and soft tissues are recorded on a computer or special X-ray film. Dense structures that block the passage of the X-ray beam through the body, such as bones, appear white. Softer body tissues, ...

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Info Images/Videos About Us News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ...

  5. X-Ray Tomographic Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Bonnie Schmittberger

    2010-08-25

    Tomographic scans have revolutionized imaging techniques used in medical and biological research by resolving individual sample slices instead of several superimposed images that are obtained from regular x-ray scans. X-Ray fluorescence computed tomography, a more specific tomography technique, bombards the sample with synchrotron x-rays and detects the fluorescent photons emitted from the sample. However, since x-rays are attenuated as they pass through the sample, tomographic scans often produce images with erroneous low densities in areas where the x-rays have already passed through most of the sample. To correct for this and correctly reconstruct the data in order to obtain the most accurate images, a program employing iterative methods based on the inverse Radon transform was written. Applying this reconstruction method to a tomographic image recovered some of the lost densities, providing a more accurate image from which element concentrations and internal structure can be determined.

  6. RADIATION LOAD IN THE PROCESS OF X-RAY DIAGNOSTICS WITH THE USE OF MICROFOCUS METHODS

    Directory of Open Access Journals (Sweden)

    N. N. Potrakhov

    2008-01-01

    Full Text Available The article regards the perspectives of microfocus X-ray equipment implementation in the medical X-ray diagnostics. It demonstrates the advantages of suggested equipment in comparison with traditional X-ray diagnostic machines with the big focus in the terms of dental X-ray diagnostics. The article shows the significant patient's exposure doses reduction with improving of diagnostic quality of the obtained images. It emphasizes the need of the regulatory basis of the enhancement for microfocus machines application in X-ray diagnostics.

  7. RADIATION LOAD IN THE PROCESS OF X-RAY DIAGNOSTICS WITH THE USE OF MICROFOCUS METHODS

    OpenAIRE

    N. N. Potrakhov; A. Ju. Griaznov; A. N. Barkovsky

    2008-01-01

    The article regards the perspectives of microfocus X-ray equipment implementation in the medical X-ray diagnostics. It demonstrates the advantages of suggested equipment in comparison with traditional X-ray diagnostic machines with the big focus in the terms of dental X-ray diagnostics. The article shows the significant patient's exposure doses reduction with improving of diagnostic quality of the obtained images. It emphasizes the need of the regulatory basis of the enhancement for microfocu...

  8. Semiconductor X-ray detectors

    CERN Document Server

    Lowe, Barrie Glyn

    2014-01-01

    Identifying and measuring the elemental x-rays released when materials are examined with particles (electrons, protons, alpha particles, etc.) or photons (x-rays and gamma rays) is still considered to be the primary analytical technique for routine and non-destructive materials analysis. The Lithium Drifted Silicon (Si(Li)) X-Ray Detector, with its good resolution and peak to background, pioneered this type of analysis on electron microscopes, x-ray fluorescence instruments, and radioactive source- and accelerator-based excitation systems. Although rapid progress in Silicon Drift Detectors (SDDs), Charge Coupled Devices (CCDs), and Compound Semiconductor Detectors, including renewed interest in alternative materials such as CdZnTe and diamond, has made the Si(Li) X-Ray Detector nearly obsolete, the device serves as a useful benchmark and still is used in special instances where its large, sensitive depth is essential. Semiconductor X-Ray Detectors focuses on the history and development of Si(Li) X-Ray Detect...

  9. Characterizing Complexity of Containerized Cargo X-ray Images

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guangxing [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Martz, Harry [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Glenn, Steven [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Divin, Charles [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Birrer, Nat [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-08-19

    X-ray imaging can be used to inspect cargos imported into the United States. In order to better understand the performance of X-ray inspection systems, the X-ray characteristics (density, complexity) of cargo need to be quantified. In this project, an image complexity measure called integrated power spectral density (IPSD) was studied using both DNDO engineered cargos and stream-of-commerce (SOC) cargos. A joint distribution of cargo density and complexity was obtained. A support vector machine was used to classify the SOC cargos into four categories to estimate the relative fractions.

  10. X-Ray Optics Research

    Science.gov (United States)

    1990-09-20

    OF FUNDING NUMBERS Building 410 PORM POET TS OKUI Bolig FBDC2032648ELEMENT NO. NO. NO ACCESiON NO 11. TITLE (include Security Classification) X - Ray Optics Research...by block number) This report describes work conducted during the period I October 1987 through 30 April 1990, under Contract AFOSR-88-00l0, " X - Ray Optics Research...growth and structure of multilayer interfaces. This capability is central to the development of future materials for multilayer x - ray optics , because

  11. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... for more information about pregnancy and x-rays. A Word About Minimizing Radiation Exposure Special care is ... code: Phone no: Thank you! Do you have a personal story about radiology? Share your patient story ...

  12. X-Ray Assembler Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — Federal regulations require that an assembler who installs one or more certified components of a diagnostic x-ray system submit a report of assembly. This database...

  13. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... of any bone in the body, including the hand, wrist, arm, elbow, shoulder, spine, pelvis, hip, thigh, ... to current x-ray images for diagnosis and disease management. top of page How is the procedure ...

  14. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available Toggle navigation ... x-ray uses a very small dose of ionizing radiation to produce pictures of any bone in the body. It is commonly used to diagnose fractured bones or joint dislocation. Bone ...

  15. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... to produce pictures of any bone in the body. It is commonly used to diagnose fractured bones ... x-rays involves exposing a part of the body to a small dose of ionizing radiation to ...

  16. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... replacement and fracture reductions. look for injury, infection, arthritis , abnormal bone growths and bony changes seen in ... injuries, including fractures, and joint abnormalities, such as arthritis. X-ray equipment is relatively inexpensive and widely ...

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... or in bones. top of page How should I prepare? Most bone x-rays require no special ... to 10 minutes. top of page What will I experience during and after the procedure? A bone ...

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... examination may also be necessary so that any change in a known abnormality can be monitored over ...

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ... emergency rooms, physician offices, ambulatory care centers, nursing homes and other locations, making it convenient for both ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patient. top of page How does the procedure work? X-rays are a form of radiation like ... taken of the unaffected limb, or of a child's growth plate (where new bone is forming), for ...

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the patient in a hospital bed or the emergency room. The x-ray tube is connected to ... equipment is relatively inexpensive and widely available in emergency rooms, physician offices, ambulatory care centers, nursing homes ...

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... will analyze the images and send a signed report to your primary care or referring physician , who ... Medicine Radiation Safety How to Read Your Radiology Report Images related to X-ray (Radiography) - Bone Sponsored ...

  3. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... fracture. guide orthopedic surgery, such as spine repair/fusion, joint replacement and fracture reductions. look for injury, ... CT Exams Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety How to Read Your Radiology ...

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... here Images × Image Gallery Radiological technologist preparing to take an arm x-ray on a patient. View ... and/or your insurance provider to get a better understanding of the possible charges you will incur. ...

  5. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... in evaluating the hips of children with congenital problems. top of page This page was reviewed on ... Exams Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety How to Read Your Radiology Report ...

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... white on the x-ray, soft tissue shows up in shades of gray and air appears black. ... who will discuss the results with you. Follow-up examinations may be necessary. Your doctor will explain ...

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the baby. See the Safety page for more information about pregnancy and x-rays. top of page ... procedure varies. See the Safety page for more information about radiation dose. Women should always inform their ...

  8. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... a large photographic negative). Today, most images are digital files that are stored electronically. These stored images ... and places the x-ray film holder or digital recording plate under the table in the area ...

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... tissue shows up in shades of gray and air appears black. Until recently, x-ray images were ... imaged. When necessary, sandbags, pillows or other positioning devices will be used to help you maintain the ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... procedure varies. See the Safety page for more information about radiation dose. Women should always inform their ...

  11. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patient. top of page How does the procedure work? X-rays are a form of radiation like ... little information about muscles, tendons or joints. An MRI may be more useful in identifying bone and ...

  12. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... The teddy bear denotes child-specific content. Related Articles and Media Arthritis X-ray, Interventional Radiology and ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  13. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... very small dose of ionizing radiation to produce pictures of any bone in the body. It is ... a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays ...

  14. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... pelvis, hip, thigh, knee, leg (shin), ankle or foot. top of page What are some common uses ... to current x-ray images for diagnosis and disease management. top of page How is the procedure ...

  15. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... commonly used to diagnose fractured bones or joint dislocation. Bone x-rays are the fastest and easiest ... is used to: diagnose fractured bones or joint dislocation. demonstrate proper alignment and stabilization of bony fragments ...

  16. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown. ... appliances, eye glasses and any metal objects or clothing that might interfere with the x-ray images. ...

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... in metabolic conditions. assist in the detection and diagnosis of bone cancer . locate foreign objects in soft ... frequently compared to current x-ray images for diagnosis and disease management. top of page How is ...

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patient. top of page How does the procedure work? X-rays are a form of radiation like ... radiation dose for this procedure varies. See the Safety page for more information about radiation dose. Women ...

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... a form of radiation like light or radio waves. X-rays pass through most objects, including the ... individual patient's condition. Ultrasound imaging, which uses sound waves instead of ionizing radiation to create diagnostic images, ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... for more information about pregnancy and x-rays. A Word About Minimizing Radiation Exposure Special care is ... taking our brief survey: Survey Do you have a personal story about radiology? Share your patient story ...

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to ... See the Safety page for more information about pregnancy and x-rays. top of page What does ...

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... evaluation with additional views or a special imaging technique. A follow-up examination may also be necessary ... radiology protection organizations continually review and update the technique standards used by radiology professionals. Modern x-ray ...

  3. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... is commonly used to diagnose fractured bones or joint dislocation. Bone x-rays are the fastest and ... to view and assess bone fractures, injuries and joint abnormalities. This exam requires little to no special ...

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... information you were looking for? Yes No Please type your comment or suggestion into the following text ...

  5. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... small burst of radiation that passes through the body, recording an image on photographic film or a special detector. Different parts of the body absorb the x-rays in varying degrees. Dense ...

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... bone in the body, including the hand, wrist, arm, elbow, shoulder, spine, pelvis, hip, thigh, knee, leg ( ... x-ray tube is connected to a flexible arm that is extended over the patient while an ...

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... top of page What are the benefits vs. risks? Benefits Bone x-rays are the fastest and ... in the typical diagnostic range for this exam. Risks There is always a slight chance of cancer ...

  8. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... pass through them. As a result, bones appear white on the x-ray, soft tissue shows up ... for a physician to view and assess bone injuries, including fractures, and joint abnormalities, such as arthritis. ...

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... abnormal bone growths and bony changes seen in metabolic conditions. assist in the detection and diagnosis of ... have very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... may also be asked to remove jewelry, removable dental appliances, eye glasses and any metal objects or clothing that might interfere with the x-ray images. Women should always inform their physician and ...

  11. X-ray fluorescence holography

    CERN Document Server

    Hayashi, K; Takahashi, Y

    2003-01-01

    X-ray fluorescence holography (XFH) is a new structural analysis method of determining a 3D atomic arrangement around fluorescing atoms. We developed an XFH apparatus using advanced X-ray techniques and succeeded in obtaining high-quality hologram data. Furthermore, we introduced applications to the structural analysis of a thin film and the environment around dopants and, discussed the quantitative analysis of local lattice distortion. (author)

  12. Accelerator x-ray sources

    CERN Document Server

    Talman, Richard

    2007-01-01

    This first book to cover in-depth the generation of x-rays in particle accelerators focuses on electron beams produced by means of the novel Energy Recovery Linac (ERL) technology. The resulting highly brilliant x-rays are at the centre of this monograph, which continues where other books on the market stop. Written primarily for general, high energy and radiation physicists, the systematic treatment adopted by the work makes it equally suitable as an advanced textbook for young researchers.

  13. Why Do I Need X-Rays?

    Science.gov (United States)

    ... Child at Risk for Early Childhood Tooth Decay? Pacifiers Have Negative and Positive Effects The History of ... Sets the Record Straight on Dental X-Rays Types of X-Rays X-Rays Help Predict Permanent ...

  14. Center for X-Ray Optics, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    This report discusses the following topics: Center for X-Ray Optics; Soft X-Ray Imaging wit Zone Plate Lenses; Biological X-Ray microscopy; Extreme Ultraviolet Lithography for Nanoelectronic Pattern Transfer; Multilayer Reflective Optics; EUV/Soft X-ray Reflectometer; Photoemission Microscopy with Reflective Optics; Spectroscopy with Soft X-Rays; Hard X-Ray Microprobe; Coronary Angiography; and Atomic Scattering Factors.

  15. Nanofocusing refractive X-ray lenses

    Energy Technology Data Exchange (ETDEWEB)

    Boye, Pit

    2010-02-05

    This thesis is concerned with the optimization and development of the production of nanofocusing refractive X-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution X-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. In this work, the theoretical basics of X-rays and their interaction with matter are described. Especially, aspects of synchrotron radiation are emphasized. Important in X-ray microscopy are the different optics. The details, advantages and disadvantages, in particular those of refractive lenses are given. To achieve small X-ray beams well beyond the 100 nm range a small focal length is required. This is achieved in refractive lenses by moving to a compact lens design where several single lenses are stacked behind each other. The, so-called nanofocusing refractive lenses (NFLs) have a parabolic cylindrical shape with lateral structure sizes in the micrometer range. NFLs are produced by using micro-machining techniques. These micro-fabrication processes and technologies are introduced. The results of the optimization and the final fabrication process for silicon lenses are presented. Subsequently, two experiments that are exemplary for the use of NFLs, are introduced. The rst one employs a high-resolution scanning fluorescence mapping of a geological sample, and the second one is a coherent x-ray diffraction imaging (CXDI) experiment. CXDI is able to reconstruct the illuminated object from recorded coherent diffraction patterns. In a scanning mode, referred to as ptychography, this method is even able to reconstruct the illumination and the object simultaneously. Especially the reconstructed illumination and the possibility of computed propagation of the wave field along the

  16. Thin Cryogenic X-ray Windows

    CERN Document Server

    Niinikoski, T O; Davenport, M; Elias, N; Aune, S; Franz, J

    2009-01-01

    We describe the construction and tests of cryogenic X-ray windows of 47 mm diameter made of 15 ìm thick polypropylene foil glued on a UHV flange and supported with a strongback mesh machined by electro-erosion. These hermetic windows of the solar axion telescope of the CAST experiment at CERN withstand the static and dynamic pressures of the buffer gas that are normally below 130 mbar, but may reach 1.2 bar when the magnet quenches. They were tested at 60 K up to 3.5 bar static pressure without permanent deformation.

  17. Aviation security x-ray detection challenges

    Science.gov (United States)

    Harvey, T.

    2016-05-01

    In this paper, a review of the background and some drivers are provided for X-ray screening for aviation security. Some of the key considerations are highlighted along with impacts of the image-based approaches and signature approaches. The role of information theory is discussed along with some recent work that may influence the technical direction by posing the question: "what measurements, parameters and metrics should be considered in future system design?" A path forward should be based on information theory, however electronic machines will likely interface with humans and be dollar-cost driven, so ultimately solutions must consider additional parameters other than only technical performance factors.

  18. Soft x-ray excitonics

    Science.gov (United States)

    Moulet, A.; Bertrand, J. B.; Klostermann, T.; Guggenmos, A.; Karpowicz, N.; Goulielmakis, E.

    2017-09-01

    The dynamic response of excitons in solids is central to modern condensed-phase physics, material sciences, and photonic technologies. However, study and control have hitherto been limited to photon energies lower than the fundamental band gap. Here we report application of attosecond soft x-ray and attosecond optical pulses to study the dynamics of core-excitons at the L2,3 edge of Si in silicon dioxide (SiO2). This attosecond x-ray absorption near-edge spectroscopy (AXANES) technique enables direct probing of the excitons’ quasiparticle character, tracking of their subfemtosecond relaxation, the measurement of excitonic polarizability, and observation of dark core-excitonic states. Direct measurement and control of core-excitons in solids lay the foundation of x-ray excitonics.

  19. X-ray tensor tomography

    Science.gov (United States)

    Malecki, A.; Potdevin, G.; Biernath, T.; Eggl, E.; Willer, K.; Lasser, T.; Maisenbacher, J.; Gibmeier, J.; Wanner, A.; Pfeiffer, F.

    2014-02-01

    Here we introduce a new concept for x-ray computed tomography that yields information about the local micro-morphology and its orientation in each voxel of the reconstructed 3D tomogram. Contrary to conventional x-ray CT, which only reconstructs a single scalar value for each point in the 3D image, our approach provides a full scattering tensor with multiple independent structural parameters in each volume element. In the application example shown in this study, we highlight that our method can visualize sub-pixel fiber orientations in a carbon composite sample, hence demonstrating its value for non-destructive testing applications. Moreover, as the method is based on the use of a conventional x-ray tube, we believe that it will also have a great impact in the wider range of material science investigations and in future medical diagnostics. The authors declare no competing financial interests.

  20. Thin Films for X-ray Optics

    Science.gov (United States)

    Conley, Raymond

    Laue lens, however my advancements in MLL fabrication technology led to new generations of deposition instruments that were better suited. In order to re-purpose the APS Rotary Deposition System, a concept to upgrade the machine with a suborbital planetary is discussed. The APS Modular Deposition System (MDS) is the state of the art instrument that was designed to keep APS at the forefront of x-ray optics technology for the foreseeable future. By including flexibility in the design, the machine is ideally suited for research on all types of multilayers and thin-films for x-ray optics applications. A new method for in-situ surface metrology is presented which relies on the infrastructure provided by the MDS. The chapter concludes with discussion on several types of reflective multilayers that span a broad range of x-ray wavelengths, from soft x-rays (below 5-10 keV) to hard x-rays (above 5-10keV). A method for fabrication of precision elliptically-figured mirrors called profile coating (conceived at the APS) is covered in Chapter 3. Profile-coating is a technique where a specially shaped mask is designed to partially obscure the sputtering source in order to produce a coating with a specially defined film thickness profile perpendicular to substrate translation. Source shape modeling and mask calculation is presented. Initially, Au was used as the filler material for profile coating, however I found that Pt offered better performance. Rh has also been used to fabricate profile-coated KB mirrors. Performance and commissioning results for the APS profile-coating deposition system (another machine designed by myself) is included. Chapter 4 covers my work on multilayer Laue lens. Motivation and current status are presented, and the nomenclature we devised to name the various MLL types is listed. Following this, a theoretical overview is provided. Important advancements I have spearhead in this field are included, such as the introduction of metal silicides, reactive

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... dislocations. In elderly or patients with osteoporosis, a hip fracture may be clearly seen on a CT scan, while it may be barely seen, if at all, on a hip x-ray. For suspected spine injury or other ...

  3. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos ... to current x-ray images for diagnosis and disease management. top of page How is the procedure ...

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... small burst of radiation that passes through the body, recording an image on photographic film or a special detector. Different ... This ensures that those parts of a patient's body not being imaged receive minimal radiation ... x-ray images are among the clearest, most detailed views of ...

  5. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patient. top of page How does the procedure work? X-rays are a form of radiation like ... may be placed over your pelvic area or breasts when feasible to protect from ... chance of cancer from excessive exposure to radiation. However, the benefit ...

  6. Stellar X-Ray Polarimetry

    Science.gov (United States)

    Swank, J.

    2011-01-01

    Most of the stellar end-state black holes, pulsars, and white dwarfs that are X-ray sources should have polarized X-ray fluxes. The degree will depend on the relative contributions of the unresolved structures. Fluxes from accretion disks and accretion disk corona may be polarized by scattering. Beams and jets may have contributions of polarized emission in strong magnetic fields. The Gravity and Extreme Magnetism Small Explorer (GEMS) will study the effects on polarization of strong gravity of black holes and strong magnetism of neutron stars. Some part of the flux from compact stars accreting from companion stars has been reflected from the companion, its wind, or accretion streams. Polarization of this component is a potential tool for studying the structure of the gas in these binary systems. Polarization due to scattering can also be present in X-ray emission from white dwarf binaries and binary normal stars such as RS CVn stars and colliding wind sources like Eta Car. Normal late type stars may have polarized flux from coronal flares. But X-ray polarization sensitivity is not at the level needed for single early type stars.

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... is commonly used to diagnose fractured bones or joint dislocation. Bone x-rays are the fastest and easiest way for your doctor ... shin), ankle or foot. top of page What are some common uses of the ... bones or joint dislocation. demonstrate proper alignment and stabilization of bony ...

  8. X-rays and magnetism.

    Science.gov (United States)

    Fischer, Peter; Ohldag, Hendrik

    2015-09-01

    Magnetism is among the most active and attractive areas in modern solid state physics because of intriguing phenomena interesting to fundamental research and a manifold of technological applications. State-of-the-art synthesis of advanced magnetic materials, e.g. in hybrid structures paves the way to new functionalities. To characterize modern magnetic materials and the associated magnetic phenomena, polarized x-rays have emerged as unique probes due to their specific interaction with magnetic materials. A large variety of spectroscopic and microscopic techniques have been developed to quantify in an element, valence and site-sensitive way properties of ferro-, ferri-, and antiferromagnetic systems, such as spin and orbital moments, and to image nanoscale spin textures and their dynamics with sub-ns time and almost 10 nm spatial resolution. The enormous intensity of x-rays and their degree of coherence at next generation x-ray facilities will open the fsec time window to magnetic studies addressing fundamental time scales in magnetism with nanometer spatial resolution. This review will give an introduction into contemporary topics of nanoscale magnetic materials and provide an overview of analytical spectroscopy and microscopy tools based on x-ray dichroism effects. Selected examples of current research will demonstrate the potential and future directions of these techniques.

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... small burst of radiation that passes through the body, recording an image on photographic film or a special detector. Different ... bear denotes child-specific content. Related Articles and Media ... Images related to X-ray (Radiography) - Bone Sponsored by ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone ...

  11. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... evaluated). MRI can also detect subtle or occult fractures or bone bruises (also called bone contusions or microfractures) not visible on x-ray images. CT is being used widely to assess trauma patients in ... fractures, subtle fractures or dislocations. In elderly or patients ...

  12. X-Ray Exam: Pelvis

    Science.gov (United States)

    ... pelvis and an image is recorded on special film or a computer. This image shows the bones of the pelvis, which include the two hip bones, plus the sacrum and the coccyx (tailbone). The X-ray image is black and white. Dense body parts that block the passage of the X- ...

  13. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to ... See the Safety page for more information about pregnancy and x-rays. A Word About Minimizing ... imaging tests and treatments have special pediatric considerations. The teddy ...

  14. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... way for your doctor to view and assess bone fractures, injuries and joint abnormalities. This exam requires little ... way for a physician to view and assess bone injuries, including fractures, and joint abnormalities, such as arthritis. X-ray ...

  15. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... for a physician to view and assess bone injuries, including fractures, and joint abnormalities, such as arthritis. X-ray equipment is relatively inexpensive and widely available in emergency rooms, physician offices, ambulatory care centers, nursing homes and other locations, making it ...

  16. High-Resolution X-ray Emission and X-ray Absorption Spectroscopy

    NARCIS (Netherlands)

    Groot, F.M.F. de

    2000-01-01

    In this review, high-resolution X-ray emission and X-ray absorption spectroscopy will be discussed. The focus is on the 3d transition-metal systems. To understand high-resolution X-ray emission and reso-nant X-ray emission, it is first necessary to spend some time discussing the X-ray absorption

  17. A simple X-ray emitter.

    Science.gov (United States)

    Murakami, Hiroaki; Ono, Ryoichi; Hirai, Atsuhiko; Hosokawa, Yoshinori; Kawai, Jun

    2005-07-01

    A compact X-ray emission instrument is made, and the X-ray spectra are measured by changing the applied electric potential. Strong soft X-rays are observed when evacuating roughly and applying a high voltage to an insulator settled in this device. The X-ray intensity is higher as the applied voltage is increased. A light-emitting phenomenon is observed when this device emits X-rays. The present X-ray emitter is made of a small cylinder with a radius of 20 mm and a height of 50 mm. This X-ray generator has a potential to be used as an X-ray source in an X-ray fluorescence spectrometer.

  18. Effective X-ray beam size measurements of an X-ray tube and polycapillary X-ray lens system using a scanning X-ray fluorescence method

    Energy Technology Data Exchange (ETDEWEB)

    Gherase, Mihai R., E-mail: mgherase@csufresno.edu; Vargas, Andres Felipe

    2017-03-15

    Size measurements of an X-ray beam produced by an integrated polycapillary X-ray lens (PXL) and X-ray tube system were performed by means of a scanning X-ray fluorescence (SXRF) method using three different metallic wires. The beam size was obtained by fitting the SXRF data with the analytical convolution between a Gaussian and a constant functions. For each chemical element in the wire an effective energy was calculated based on the incident X-ray spectrum and its photoelectric cross section. The proposed method can be used to measure the effective X-ray beam size in XRF microscopy studies.

  19. Diffractive X-ray Telescopes

    OpenAIRE

    Skinner, Gerald K

    2010-01-01

    Diffractive X-ray telescopes using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution several orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted space- time in the immediate vicinity of the super...

  20. Review of x-ray free-electron laser theory

    Directory of Open Access Journals (Sweden)

    Zhirong Huang

    2007-03-01

    Full Text Available High-gain free-electron lasers (FELs are being developed as extremely bright sources for a next-generation x-ray facility. In this paper, we review the basic theory of the start-up, the exponential growth, and the saturation of the high-gain process, emphasizing the self-amplified spontaneous emission. The radiation characteristics of an x-ray FEL, including its transverse coherence, temporal characteristics, and harmonic content, are discussed. FEL performance in the presence of machine errors and undulator wakefields is examined. Various enhancement schemes through seeding and beam manipulations are summarized.

  1. FPGA-Based X-Ray Detection and Measurement for an X-Ray Polarimeter

    Science.gov (United States)

    Gregory, Kyle; Hill, Joanne; Black, Kevin; Baumgartner, Wayne

    2013-01-01

    This technology enables detection and measurement of x-rays in an x-ray polarimeter using a field-programmable gate array (FPGA). The technology was developed for the Gravitational and Extreme Magnetism Small Explorer (GEMS) mission. It performs precision energy and timing measurements, as well as rejection of non-x-ray events. It enables the GEMS polarimeter to detect precisely when an event has taken place so that additional measurements can be made. The technology also enables this function to be performed in an FPGA using limited resources so that mass and power can be minimized while reliability for a space application is maximized and precise real-time operation is achieved. This design requires a low-noise, charge-sensitive preamplifier; a highspeed analog to digital converter (ADC); and an x-ray detector with a cathode terminal. It functions by computing a sum of differences for time-samples whose difference exceeds a programmable threshold. A state machine advances through states as a programmable number of consecutive samples exceeds or fails to exceed this threshold. The pulse height is recorded as the accumulated sum. The track length is also measured based on the time from the start to the end of accumulation. For track lengths longer than a certain length, the algorithm estimates the barycenter of charge deposit by comparing the accumulator value at the midpoint to the final accumulator value. The design also employs a number of techniques for rejecting background events. This innovation enables the function to be performed in space where it can operate autonomously with a rapid response time. This implementation combines advantages of computing system-based approaches with those of pure analog approaches. The result is an implementation that is highly reliable, performs in real-time, rejects background events, and consumes minimal power.

  2. Note: Tangential x-ray diagnosis for investigating fast MHD events in EAST tokamak.

    Science.gov (United States)

    Li, Erzhong; Hu, Liqun; Chen, Kaiyun; Zhang, Jizong; Chen, Yiebin; Zhou, Ruijie; Gan, Kaifu; Liu, Yong

    2010-10-01

    A tangential x-ray diagnosis has been installed in the experimental advanced superconducting tokamakvacuum vessel for the study of fast magnetohydrodynamics (MHD) events. This system is based on absolute x-ray ultraviolet detectors with a collimator which is processed by laser machine. The first experimental results have proved its ability to measure the small-scale and transient MHD perturbations.

  3. Development of a 3-D X-ray system

    Science.gov (United States)

    Evans, James Paul Owain

    The interpretation of standard two-dimensional x-ray images by humans is often very difficult. This is due to the lack of visual cues to depth in an image which has been produced by transmitted radiation. The solution put forward in this research is to introduce binocular parallax, a powerful physiological depth cue, into the resultant shadowgraph x-ray image. This has been achieved by developing a binocular stereoscopic x-ray imaging technique, which can be used for both visual inspection by human observers and also for the extraction of three-dimensional co-ordinate information. The technique is implemented in the design and development of two experimental x-ray systems and also the development of measurement algorithms. The first experimental machine is based on standard linear x-ray detector arrays and was designed as an optimum configuration for visual inspection by human observers. However, it was felt that a combination of the 3-D visual inspection capability together with a measurement facility would enhance the usefulness of the technique. Therefore, both a theoretical and an empirical analysis of the co-ordinate measurement capability of the machine has been carried out. The measurement is based on close-range photogrammetric techniques. The accuracy of the measurement has been found to be of the order of 4mm in x, 3mm in y and 6mm in z. A second experimental machine was developed and based on the same technique as that used for the first machine. However, a major departure has been the introduction of a dual energy linear x-ray detector array which will allow, in general, the discrimination between organic and inorganic substances. The second design is a compromise between ease of visual inspection for human observers and optimum three-dimensional co-ordinate measurement capability. The system is part of an on going research programme into the possibility of introducing psychological depth cues into the resultant x-ray images. The research presented in

  4. Cryotomography x-ray microscopy state

    Science.gov (United States)

    Le Gros, Mark; Larabell, Carolyn A.

    2010-10-26

    An x-ray microscope stage enables alignment of a sample about a rotation axis to enable three dimensional tomographic imaging of the sample using an x-ray microscope. A heat exchanger assembly provides cooled gas to a sample during x-ray microscopic imaging.

  5. Center for X-ray Optics, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1989-04-01

    This report briefly reviews the following topics: soft-x-ray imaging; reflective optics for hard x-rays; coherent XUV sources; spectroscopy with x-rays; detectors for coronary artery imaging; synchrotron-radiation optics; and support for the advanced light source.

  6. X-Ray Exam: Scoliosis (For Parents)

    Science.gov (United States)

    ... for Educators Search English Español X-Ray Exam: Scoliosis KidsHealth / For Parents / X-Ray Exam: Scoliosis What's in this article? What It Is Why ... You Have Questions Print What It Is A scoliosis X-ray is a relatively safe and painless ...

  7. Techniques in X-ray Astronomy

    Indian Academy of Sciences (India)

    ray telescopes in space, leading to a veritable revolution. Stich telescopes require distortion free focusing of X-rays and the use of position sensitive X- ray detectors. In this article I shall describe the importance of X-ray imaging, the optical ...

  8. Ancient administrative handwritten documents: X-ray analysis and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Albertin, F., E-mail: fauzia.albertin@epfl.ch [Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Astolfo, A. [Paul Scherrer Institut (PSI), Villigen (Switzerland); Stampanoni, M. [Paul Scherrer Institut (PSI), Villigen (Switzerland); ETHZ, Zürich (Switzerland); Peccenini, Eva [University of Ferrara (Italy); Technopole of Ferrara (Italy); Hwu, Y. [Academia Sinica, Taipei, Taiwan (China); Kaplan, F. [Ecole Polytechnique Fédérale de Lausanne (EPFL) (Switzerland); Margaritondo, G. [Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2015-01-30

    The heavy-element content of ink in ancient administrative documents makes it possible to detect the characters with different synchrotron imaging techniques, based on attenuation or refraction. This is the first step in the direction of non-interactive virtual X-ray reading. Handwritten characters in administrative antique documents from three centuries have been detected using different synchrotron X-ray imaging techniques. Heavy elements in ancient inks, present even for everyday administrative manuscripts as shown by X-ray fluorescence spectra, produce attenuation contrast. In most cases the image quality is good enough for tomography reconstruction in view of future applications to virtual page-by-page ‘reading’. When attenuation is too low, differential phase contrast imaging can reveal the characters from refractive index effects. The results are potentially important for new information harvesting strategies, for example from the huge Archivio di Stato collection, objective of the Venice Time Machine project.

  9. Theory and Modelling of Ultrafast X-ray Imaging of Dynamical Non-equilibrium Systems

    DEFF Research Database (Denmark)

    Lorenz, Ulf

    Over the next few years, a new generation of x-ray sources is going online. These freeelectron lasers will provide extremely bright subpicosecond x-ray pulses. Traditionally, x-ray diraction has the advantage of directly determining the atomic positions within a sample. With these new machines......, it becomes feasible to exploit this concept for ultrafast processes; in eect, we can study chemical reactions as they occur. This thesis deals with theoretical aspect of ultrafast time-resolved x-ray diraction (TRXD).We derive general formulas for calculating the diraction signal that are closely related...

  10. Development of a 3-D x-ray system

    CERN Document Server

    Evans, J P O

    1993-01-01

    major departure has been the introduction of a dual energy linear x-ray detector array which will allow, in general, the discrimination between organic and inorganic substances. The second design is a compromise between ease of visual inspection for human observers and optimum three-dimensional co-ordinate measurement capability. The system is part of an on going research programme into the possibility of introducing psychological depth cues into the resultant x-ray images. The research presented in this thesis was initiated to enhance the visual interpretation of complex x-ray images, specifically in response to problems encountered in the routine screening of freight by HM. Customs and Excise. This phase of the work culminated in the development of the first experimental machine. During this work the security industry was starting to adopt a new type of x-ray detector, namely the dual energy x-ray sensor. The Department of Transport made available funding to the Police Scientific Development Branch (P.S.D.B...

  11. X-ray total reflection mirrors for coherent illumination

    CERN Document Server

    Ishikawa, T; Yabashi, M; Souvorov, A; Yamauchi, K; Yamamura, K; Mimura, H; Saito, A; Mori, Y

    2002-01-01

    X-ray mirrors for coherent illumination demand much higher surface quality than is achievable with the conventional polishing techniques. Plasma chemical vaporization machining (CVM) and elastic emission machining (EEM) have been applied for x-ray mirror manufacturing. Figure error of a flat silicon single crystal mirrors made with CVM+EEM process was reduced to 2.0 nm peak-to-valley and 0.2 nm RMS. The machining process was also applied to make elliptical mirrors. One-dimensional focusing with a single elliptical mirror showed diffraction-limited properties with the focal width of 200 nm. Two-dimensional focusing with Kirkpatric-Baez configuration gave a focal spot size of 200 nm x 200 nm. (author)

  12. Method for spatially modulating X-ray pulses using MEMS-based X-ray optics

    Science.gov (United States)

    Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

    2015-03-10

    A method and apparatus are provided for spatially modulating X-rays or X-ray pulses using microelectromechanical systems (MEMS) based X-ray optics. A torsionally-oscillating MEMS micromirror and a method of leveraging the grazing-angle reflection property are provided to modulate X-ray pulses with a high-degree of controllability.

  13. NIKOLA TESLA AND THE X-RAY

    OpenAIRE

    Rade R. Babic

    2005-01-01

    After professor Wilhelm Konrad Röntgen published his study of an x-ray discovery (Academy Bulletin, Berlin, 08. 11. 1895.), Nikola Tesla published his first study of an x-ray on the 11th of March in 1896. (X-ray, Electrical Review). Until the 11th of August in 1897 he had published ten studies on this subject. All Tesla,s x-ray studies were experimental, which is specific to his work. Studying the nature of the x-ray, he established a new medical branch-radiology. He wrote:” There’s no doubt...

  14. X-ray Spectroscopy of Cooling Cluster

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, J.R.; /SLAC; Fabian, A.C.; /Cambridge U., Inst. of Astron.

    2006-01-17

    We review the X-ray spectra of the cores of clusters of galaxies. Recent high resolution X-ray spectroscopic observations have demonstrated a severe deficit of emission at the lowest X-ray temperatures as compared to that expected from simple radiative cooling models. The same observations have provided compelling evidence that the gas in the cores is cooling below half the maximum temperature. We review these results, discuss physical models of cooling clusters, and describe the X-ray instrumentation and analysis techniques used to make these observations. We discuss several viable mechanisms designed to cancel or distort the expected process of X-ray cluster cooling.

  15. Toward active x-ray telescopes II

    Science.gov (United States)

    O'Dell, Stephen L.; Aldcroft, Thomas L.; Atkins, Carolyn; Button, Timothy W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peter; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Johnson-Wilke, Raegan L.; Kolodziejczak, Jeffery J.; Lillie, Charles F.; Michette, Alan G.; Ramsey, Brian D.; Reid, Paul B.; Rodriguez Sanmartin, Daniel; Saha, Timo T.; Schwartz, Daniel A.; Trolier-McKinstry, Susan E.; Ulmer, Melville P.; Wilke, Rudeger H. T.; Willingale, Richard; Zhang, William W.

    2012-10-01

    In the half century since the initial discovery of an astronomical (non-solar) x-ray source, the observation time required to achieve a given sensitivity has decreased by eight orders of magnitude. Largely responsible for this dramatic progress has been the refinement of the (grazing-incidence) focusing x-ray telescope, culminating with the exquisite subarcsecond imaging performance of the Chandra X-ray Observatory. The future of x-ray astronomy relies upon the development of x-ray telescopes with larger aperture areas (technologically challenging—requiring precision fabrication, alignment, and assembly of large areas (x-ray optics. This paper discusses relevant programmatic and technological issues and summarizes current progress toward active x-ray telescopes.

  16. On stellar X-ray emission

    Science.gov (United States)

    Rosner, R.; Golub, L.; Vaiana, G. S.

    1985-01-01

    Stellar X-ray astronomy represents an entirely new astronomical discipline which has emerged during the past five years. It lies at the crossroads of solar physics, stellar physics, and general astrophysics. The present review is concerned with the main physical problems which arise in connection with a study of the stellar X-ray data. A central issue is the extent to which the extrapolation from solar physics is justified and the definition (if possible) of the limits to such extrapolation. The observational properties of X-ray emission from stars are considered along with the solar analogy and the modeling of X-ray emission from late-type stars, the modeling of X-ray emission from early-type stars, the physics of stellar X-ray emission, stellar X-ray emission in the more general astrophysical context, and future prospects.

  17. Full-field transmission x-ray imaging with confocal polycapillary x-ray optics

    OpenAIRE

    Sun, Tianxi; MacDonald, C.A.

    2013-01-01

    A transmission x-ray imaging setup based on a confocal combination of a polycapillary focusing x-ray optic followed by a polycapillary collimating x-ray optic was designed and demonstrated to have good resolution, better than the unmagnified pixel size and unlimited by the x-ray tube spot size. This imaging setup has potential application in x-ray imaging for small samples, for example, for histology specimens.

  18. Full-field transmission x-ray imaging with confocal polycapillary x-ray optics.

    Science.gov (United States)

    Sun, Tianxi; Macdonald, C A

    2013-02-07

    A transmission x-ray imaging setup based on a confocal combination of a polycapillary focusing x-ray optic followed by a polycapillary collimating x-ray optic was designed and demonstrated to have good resolution, better than the unmagnified pixel size and unlimited by the x-ray tube spot size. This imaging setup has potential application in x-ray imaging for small samples, for example, for histology specimens.

  19. Some properties of six different types of dental x-ray unit

    NARCIS (Netherlands)

    Trouerbach, W.Th.; Aken, J. van

    1965-01-01

    Forty-four x-ray machines were tested for reliability of timer and for output. A distinction was made between different types of errors, and large differences between these categories of errors were found.

  20. Diffractive X-Ray Telescopes

    Science.gov (United States)

    Skinner, Gerald K.

    2010-01-01

    Diffractive X-ray telescopes, using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution many orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted spacetime in the immediate vicinity of the super-massive black holes in the center of active galaxies. What then is precluding their immediate adoption? Extremely long focal lengths, very limited bandwidth, and difficulty stabilizing the image are the main problems. The history, and status of the development of such lenses is reviewed here and the prospects for managing the challenges that they present are discussed.

  1. The X-ray corona of Procyon

    Science.gov (United States)

    Schmitt, J. H. M. M.; Harnden, F. R., Jr.; Rosner, R.; Peres, G.; Serio, S.

    1985-01-01

    X-ray emission from the nearby system Procyon A/B (F5 IV + DF) was detected, using the IPC (Imaging Proportional Counter) on board the Einstein Observatory. Analysis of the X-ray pulse height spectrum suggests that the observed X-ray emission originates in Procyon A rather than in the white dwarf companion Procyon B, since the derived X-ray temperature, log T = 6.2, agrees well with temperatures found for quiescent solar X-ray emission. Modeling Procyon's corona with loops characterized by some apex temperature Tmax and emission length scale L, it is found that Tmax is well constrained, but L, and consequently the filling factor of the X-ray emitting gas, are essentially unconstrained even when EUV emission from the transition region is included in the analysis.

  2. Handbook of X-Ray Data

    CERN Document Server

    Zschornack, Günter

    2007-01-01

    This sourcebook is intended as an X-ray data reference for scientists and engineers working in the field of energy or wavelength dispersive X-ray spectrometry and related fields of basic and applied research, technology, or process and quality controlling. In a concise and informative manner, the most important data connected with the emission of characteristic X-ray lines are tabulated for all elements up to Z = 95 (Americium). This includes X-ray energies, emission rates and widths as well as level characteristics such as binding energies, fluorescence yields, level widths and absorption edges. The tabulated data are characterized and, in most cases, evaluated. Furthermore, all important processes and phenomena connected with the production, emission and detection of characteristic X-rays are discussed. This reference book addresses all researchers and practitioners working with X-ray radiation and fills a gap in the available literature.

  3. X-ray microdiffraction of biominerals.

    Science.gov (United States)

    Tamura, Nobumichi; Gilbert, Pupa U P A

    2013-01-01

    Biominerals have complex and heterogeneous architectures, hence diffraction experiments with spatial resolutions between 500 nm and 10 μm are extremely useful to characterize them. X-ray beams in this size range are now routinely produced at many synchrotrons. This chapter provides a review of the different hard X-ray diffraction and scattering techniques, used in conjunction with efficient, state-of-the-art X-ray focusing optics. These include monochromatic X-ray microdiffraction, polychromatic (Laue) X-ray microdiffraction, and microbeam small-angle X-ray scattering. We present some of the most relevant discoveries made in the field of biomineralization using these approaches. © 2013 Elsevier Inc. All rights reserved.

  4. Radiation safety in X-ray facilities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-01

    The guide specifies the radiation safety requirements for structural shielding and other safety arrangements used in X-ray facilities in medical and veterinary X-ray activities and in industry, research and education. The guide is also applicable to premises in which X-ray equipment intended for radiation therapy and operating at a voltage of less than 25 kV is used. The guide applies to new X-ray facilities in which X-ray equipment that has been used elsewhere is transferred. The radiation safety requirements for radiation therapy X-ray devices operating at a voltage exceeding 25 kV, and for the premices in which such devices are used, are set out in Guide ST 2.2.

  5. Handbook of X-ray Astronomy

    Science.gov (United States)

    Arnaud, Keith; Smith, Randall; Siemiginowska, Aneta; Ellis, Richard; Huchra, John; Kahn, Steve; Rieke, George; Stetson, Peter B.

    2011-11-01

    Practical guide to X-ray astronomy for graduate students, professional astronomers and researchers. Presenting X-ray optics, basic detector physics and data analysis. It introduces the reduction and calibration of X-ray data, scientific analysis, archives, statistical issues and the particular problems of highly extended sources. The appendices provide reference material often required during data analysis. The handbook web page contains figures and tables: http://xrayastronomyhandbook.com/

  6. Sandia Mark II X-Ray System

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, L.W.

    1979-11-01

    The Sandia Mark II X-Ray System was designed and developed to provide an intense source of mononergetic, ultra-soft x rays with energies between 0.282 and 1.486 keV. The x-ray tube design is similar to one developed by B.L. Henke and incorporates modifications made by Tom Ellsberry. An operations manual section is incorporated to help the experimenter/operator.

  7. X-ray data booklet. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, D. (ed.)

    1986-04-01

    A compilation of data is presented. Included are properties of the elements, electron binding energies, characteristic x-ray energies, fluorescence yields for K and L shells, Auger energies, energy levels for hydrogen-, helium-, and neonlike ions, scattering factors and mass absorption coefficients, and transmission bands of selected filters. Also included are selected reprints on scattering processes, x-ray sources, optics, x-ray detectors, and synchrotron radiation facilities. (WRF)

  8. Symbiotic Stars in X-rays

    Science.gov (United States)

    Luna, G. J. M.; Sokoloski, J. L.; Mukai, K.; Nelson, T.

    2014-01-01

    Until recently, symbiotic binary systems in which a white dwarf accretes from a red giant were thought to be mainly a soft X-ray population. Here we describe the detection with the X-ray Telescope (XRT) on the Swift satellite of 9 white dwarf symbiotics that were not previously known to be X-ray sources and one that was previously detected as a supersoft X-ray source. The 9 new X-ray detections were the result of a survey of 41 symbiotic stars, and they increase the number of symbiotic stars known to be X-ray sources by approximately 30%. Swift/XRT detected all of the new X-ray sources at energies greater than 2 keV. Their X-ray spectra are consistent with thermal emission and fall naturally into three distinct groups. The first group contains those sources with a single, highly absorbed hard component, which we identify as probably coming from an accretion-disk boundary layer. The second group is composed of those sources with a single, soft X-ray spectral component, which likely arises in a region where low-velocity shocks produce X-ray emission, i.e. a colliding-wind region. The third group consists of those sources with both hard and soft X-ray spectral components. We also find that unlike in the optical, where rapid, stochastic brightness variations from the accretion disk typically are not seen, detectable UV flickering is a common property of symbiotic stars. Supporting our physical interpretation of the two X-ray spectral components, simultaneous Swift UV photometry shows that symbiotic stars with harder X-ray emission tend to have stronger UV flickering, which is usually associated with accretion through a disk. To place these new observations in the context of previous work on X-ray emission from symbiotic stars, we modified and extended the alpha/beta/gamma classification scheme for symbiotic-star X-ray spectra that was introduced by Muerset et al. based upon observations with the ROSAT satellite, to include a new sigma classification for sources with

  9. Ultrashort X-ray pulse science

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Alan Hap [Univ. of California, Berkeley, CA (US). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    1998-05-01

    A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90° Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ~ 300 fs, 30 keV (0.4 Å) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has been demonstrated as a

  10. X-ray Observations at Gaisberg Tower

    Directory of Open Access Journals (Sweden)

    Pasan Hettiarachchi

    2018-01-01

    Full Text Available We report the occurrence of X-rays at ground level due to cloud-to-ground flashes of upward-initiated lightning from Gaisberg Tower, in Austria, which is located at an altitude of 1300 m. This is the first observation of X-ray emissions from upward lightning from a tower top located at high altitude. Measurements were carried out using scintillation detectors installed close to the tower top in two phases from 2011 to 2015. X-rays were recorded in three subsequent strokes of three flashes out of the total of 108 flashes recorded in the system during both phases. In contrast to the observations from downward natural or triggered lightning, X-rays were observed only within 10 µs before the subsequent return stroke. This shows that X-rays were emitted when the dart leader was in the vicinity of the tower top, hence during the most intense phase of the dart leader. Both the detected energy and the fluence of X-rays are far lower compared to X-rays from downward natural or rocket-triggered lightning. In addition to the above 108 flashes, an interesting observation of X-rays produced by a nearby downward flash is also presented. The shorter length of dart-leader channels in Gaisberg is suggested as a possible cause of this apparently weaker X-ray production.

  11. X-ray laser microscope apparatus

    Science.gov (United States)

    Suckewer, Szymon; DiCicco, Darrell S.; Hirschberg, Joseph G.; Meixler, Lewis D.; Sathre, Robert; Skinner, Charles H.

    1990-01-01

    A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

  12. Detector development for x-ray imaging

    Science.gov (United States)

    Mentzer, M. A.; Herr, D. A.; Brewer, K. J.; Ojason, N.; Tarpine, H. A.

    2010-02-01

    X-ray imaging requires unique optical detector system configuration for optimization of image quality, resolution, and contrast ratio. A system is described whereby x-ray photons from multiple anode sources create a series of repetitive images on fast-decay scintillator screens, from which an intensified image is transferred to a fast phosphor on a GEN II image intensifier and collected as a cineradiographic video with high speed digital imagery. The work addresses scintillator material formulation, flash x-ray implementation, image intensification, and high speed video processing and display. Novel determination of optimal scintillator absorption, x-ray energy and dose relationships, contrast ratio determination, and test results are presented.

  13. X-ray Observations of "Recycled" Pulsars

    Science.gov (United States)

    Bogdanov, Slavko

    2014-11-01

    The Chandra X-ray Observatory has been instrumental in establishing the X-ray properties of the Galactic population of rotation-powered ("recycled") millisecond pulsars. In this talk I will provide a summary of deep X-ray studies of globular cluster millisecond pulsars, as well as several nearby field millisecond pulsars. These include thermally-emitting recycled pulsars that may provide stringent constraints on the elusive neutron star equation of state, and so-called "redback" binary pulsars, which seem to sporadically revert to an X-ray binary-like state.

  14. X-ray spectrometry using polycapillary X-ray optics and position sensitive detector.

    Science.gov (United States)

    Ding, X; Xie, J; He, Y; Pan, Q; Yan, Y

    2000-10-02

    Polycapillary X-ray optics (capillary X-ray lens) are now popular in X-ray fluorescence (XRF) analysis. Such an X-ray lens can collect X-rays emitted from an X-ray source in a large solid angle and form a very intense X-ray microbeam which is very convenient for microbeam X-ray fluorescence (MXRF) analysis giving low minimum detection limits (MDLs) in energy dispersive X-ray fluorescence (EDXRF). A new method called position sensitive X-ray spectrometry (PSXS) which combines an X-ray lens used to form an intense XRF source and a position sensitive detector (PSD) used for wavelength dispersive spectrometry (WDS) measurement was developed recently in the X-ray Optics Laboratory of Institute of Low Energy Nuclear Physics (ILENP) at Beijing Normal University. Such a method can give high energy and spacial resolution and high detection efficiency simultaneously. A short view of development of both the EDXRF using a capillary X-ray lens and the new PSXS is given in this paper.

  15. Contribuição ao estudo da quilovoltagem nominal preconizada e do tempo de exposição de diferentes modelos de aparelhos de raios X odontológicos A contribution to the study of nominal kilovoltage preconized and time of exposure for different models of dental X-ray machines

    Directory of Open Access Journals (Sweden)

    Frab Norberto BOSCOLO

    1997-01-01

    Full Text Available O presente trabalho teve o propósito de avaliar o desempenho de aparelhos de raios X odontológicos com relação aos fatores ©tempo de exposiçãoª e ©quilovoltagemª. Foram estudados 127aparelhos da região Sul de Minas Gerais, comercializados pelas firmas Funk e Dabi Atlante. Os valores obtidos, tanto do tempo de exposição quanto da quilovoltagem para cada modelo de aparelho de raios X estudado, foram organizados em tabelas de distribuição de freqüência e apresentados em histogramas. Os resultados obtidos, após serem trabalhados, apontaram um desempenho para o tempo de exposição pouco satisfatório para o modelo X-10, da Funk, enquanto que os aparelhos da firma Dabi Atlante, modelos Spectro II, Trophy e Spectro 1070, mostraram desempenho satisfatório quando comparados o tempo de exposição real e o tempo de exposição nominal. Esses mesmos aparelhos tiveram a sua quilovoltagem nominal pesquisada e mostraram, no geral, uma quilovoltagem menor do que a preconizada, apontando com isso um desempenho aquém do esperado. Para tentar sanar, pelo menos em parte, as deficiências apresentadas pelos aparelhos, recomenda-se aos profissionais sua manutenção periódicaThis study intended to assess the performance of dental X-ray machines as regards time of exposure and kilovoltage with an analysis of 127 X-ray machines sold by Funk and Dabi Atlante in the South of Minas Gerais State. The values obtained, both time of exposure and kilovoltage for each model of X-ray machine studied, were organized into frequency distribution tables and presented in histograms. Results obtained, once processed, were indicative of an exposure time performance that was unsatisfactory for Funk Model X-10, whereas the Dabi Atlante machines Models Spectro II, Trophy, and Spectro 1070, proved satisfactory as to performance in a comparison of real exposure and nominal exposure times. We examined the nominal kilovoltage of these same machines and, as a whole, they

  16. Diffraction leveraged modulation of X-ray pulses using MEMS-based X-ray optics

    Science.gov (United States)

    Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

    2016-08-09

    A method and apparatus are provided for implementing Bragg-diffraction leveraged modulation of X-ray pulses using MicroElectroMechanical systems (MEMS) based diffractive optics. An oscillating crystalline MEMS device generates a controllable time-window for diffraction of the incident X-ray radiation. The Bragg-diffraction leveraged modulation of X-ray pulses includes isolating a particular pulse, spatially separating individual pulses, and spreading a single pulse from an X-ray pulse-train.

  17. X-ray Emission from Solar Flares

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Solar X-ray Spectrometer (SOXS), the first space-borne solar astronomy experiment of India was designed to improve our current understanding of X-ray emission from the Sun in general and solar flares in particular. SOXS mission is composed of two solid state detectors, viz., Si and CZT semiconductors ...

  18. Low Energy X-Ray Diagnostics - 1981.

    Science.gov (United States)

    1981-01-01

    ray Analysis, 18, 26 (1975). practicA !ity of thermal recording of intense x-rays. 2. R.P. Godwin, Adv. in X-rays Analysis, 19, 533 Many optical...the 15. T. W. Barbee Jr., in "National Science Foundation behavior of LSM dispersion elements. - Twenty Sixth Annual Report for Fiscal Year Extension

  19. Instrumental technique in X-ray astronomy

    Science.gov (United States)

    Peterson, L. E.

    1975-01-01

    A detailed review of the development of instruments for X-ray astronomy is given with major emphasis on nonfocusing high-sensitivity counter techniques used to detect cosmic photons in the energy range between 0.20 and 300 keV. The present status of X-ray astronomy is summarized together with significant results of the Uhuru observations, and photon interactions of importance for the detection of X-rays in space are noted. The three principal devices used in X-ray astronomy (proportional, scintillation, and solid-state counters) are described in detail, data-processing systems for these devices are briefly discussed, and the statistics of nuclear counting as applied to X-ray astronomy is outlined analytically. Effects of the near-earth X-ray environment and atmospheric gamma-ray production on X-ray detection by low-orbit satellites are considered. Several contemporary instruments are described (proportional-counter systems, scintillation-counter telescopes, modulation collimators), and X-ray astronomical satellite missions are tabulated.

  20. X-ray Galaxy Clusters & Cosmology

    Science.gov (United States)

    Ettori, Stefano

    2011-09-01

    I present a summary of the four lectures given on these topics: (i) Galaxy Clusters in a cosmological context: an introduction; (ii) Galaxy Clusters in X-ray: how and what we observe, limits and prospects; (iii) X-ray Galaxy Clusters and Cosmology: total mass, gas mass & systematics; (iv) Properties of the ICM: scaling laws and metallicity.

  1. Accelerator-driven X-ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-09

    After an introduction which mentions x-ray tubes and storage rings and gives a brief review of special relativity, the subject is treated under the following topics and subtopics: synchrotron radiation (bending magnet radiation, wiggler radiation, undulator radiation, brightness and brilliance definition, synchrotron radiation facilities), x-ray free-electron lasers (linac-driven X-ray FEL, FEL interactions, self-amplified spontaneous emission (SASE), SASE self-seeding, fourth-generation light source facilities), and other X-ray sources (energy recovery linacs, Inverse Compton scattering, laser wakefield accelerator driven X-ray sources. In summary, accelerator-based light sources cover the entire electromagnetic spectrum. Synchrotron radiation (bending magnet, wiggler and undulator radiation) has unique properties that can be tailored to the users’ needs: bending magnet and wiggler radiation is broadband, undulator radiation has narrow spectral lines. X-ray FELs are the brightest coherent X-ray sources with high photon flux, femtosecond pulses, full transverse coherence, partial temporal coherence (SASE), and narrow spectral lines with seeding techniques. New developments in electron accelerators and radiation production can potentially lead to more compact sources of coherent X-rays.

  2. The Beginnings of X-ray Crystallography

    Indian Academy of Sciences (India)

    IAS Admin

    Those were the days when Science was hovering around the wave–particle duality. William. Henry Bragg was toying with the idea that X-rays are particles and the observation made by Max von Laue that X-rays are diffracted by crystals could indeed lead to the understanding of crystal structures. On the other hand, his son, ...

  3. X-ray Measurements of Black Hole X-ray Binary Source GRS 1915+ ...

    Indian Academy of Sciences (India)

    tribpo

    X-ray Measurements of Black Hole X-ray Binary Source GRS. 1915+105 and the Evolution of Hard X-ray Spectrum. R. K. Manchanda, Tata Institute of Fundamental Research, Mumbai 400 005, India,. Received 1999 December 28; accepted 2000 February 9. Abstract. We report the spectral measurement of GRS 1915+105 ...

  4. The X-ray imager on AXO

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Carl; Kuvvetli, Irfan; Westergaard, Niels Jørgen Stenfeldt

    2001-01-01

    DSRI has initiated a development program of CZT X-ray and gamma-ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as the so-called drift detectors. For the electronic readout, modern ASIC chips were investigated....... Modular design and the low-power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed. One such detector system has been proposed for future space missions: the X-Ray Imager (XRI) on the Atmospheric X-ray...... Observatory (AXO), which is a mission proposed to the Danish Small Satellite Program and is dedicated to observations of X-ray generating processes in the Earth's atmosphere. Of special interest will be simultaneous optical and X-ray observations of sprites that are flashes appearing directly above an active...

  5. Hybrid scintillators for x-ray imaging

    Science.gov (United States)

    Bueno, Clifford; Rairden, Richard L.; Betz, Robert A.

    1996-04-01

    The objective of this effort is to improve x-ray absorption and light production while maintaining high spatial resolution in x-ray imaging phosphor screens. Our current target is to improve screen absorption efficiency and screen brightness by factors of 2 or greater over existing screens that have 10-1p/mm resolution. In this program, commercial phosphor screens are combined with highly absorbing, high-resolution scintillating fiber-optic (SFO) face plates to provide a hybrid sensor that exhibits superior spatial resolution, x-ray absorption, and brightness values over the phosphor material alone. These characteristics of hybrid scintillators can be adjusted to meet specific x-ray imaging requirements over a wide range of x-ray energy. This paper discusses the design, fabrication, and testing of a new series of hybrid scintillators.

  6. X-ray modeling for SMILE

    Science.gov (United States)

    Sun, T.; Wang, C.; Wei, F.; Liu, Z. Q.; Zheng, J.; Yu, X. Z.; Sembay, S.; Branduardi-Raymont, G.

    2016-12-01

    SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) is a novel mission to explore the coupling of the solar wind-magnetosphere-ionosphere system via providing global images of the magnetosphere and aurora. As the X-ray imaging is a brand new technique applied to study the large scale magnetopause, modeling of the solar wind charge exchange (SWCX) X-ray emissions in the magnetosheath and cusps is vital in various aspects: it helps the design of the Soft X-ray Imager (SXI) on SMILE, selection of satellite orbits, as well as the analysis of expected scientific outcomes. Based on the PPMLR-MHD code, we present the simulation results of the X-ray emissions in geospace during storm time. Both the polar orbit and the Molniya orbit are used. From the X-ray images of the magnetosheath and cusps, the magnetospheric responses to an interplanetary shock and IMF southward turning are analyzed.

  7. Synchrotron X-Ray Radiation and Deformation Studies

    DEFF Research Database (Denmark)

    Fæster Nielsen, Søren

    machining. The conical slit has six 25µm thick conically shaped openings matching six of the Debye-Scherrer cones from a fcc powder. By combining the conical slit with a micro-focused incoming beam of hard X-rays an embedded gauge volume is defined. Using a 2D detector, fast and complete information can...... the embedded grains within thick samples in three dimensions. All essential features like the position, volume, orien-tation, stress-state of individual grains can be determined, including the morphology of the grain boundaries. The first results obtained by using the novel tracking technique are presented...... in combination with synchrotron X-ray tomography in order to gain new in-formation on the wetting kinetics of liquid gallium in aluminium grain boundaries. Finally, an electron microscopy investigation was carried out in order to describe the lattice rotations and texture evolution in uniaxially compressed...

  8. X-Ray Background from Early Binaries

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    What impact did X-rays from the first binary star systems have on the universe around them? A new study suggests this radiation may have played an important role during the reionization of our universe.Ionizing the UniverseDuring the period of reionization, the universe reverted from being neutral (as it was during recombination, the previous period)to once again being ionized plasma a state it has remained in since then. This transition, which occurred between 150 million and one billion years after the Big Bang (redshift of 6 z 20), was caused by the formation of the first objects energetic enough to reionize the universes neutral hydrogen.ROSAT image of the soft X-ray background throughout the universe. The different colors represent different energy bands: 0.25 keV (red), 0.75 keV (green), 1.5 keV (blue). [NASA/ROSAT Project]Understanding this time period in particular, determining what sources caused the reionization, and what the properties were of the gas strewn throughout the universe during this time is necessary for us to be able to correctly interpret cosmological observations.Conveniently, the universe has provided us with an interesting clue: the large-scale, diffuse X-ray background we observe all around us. What produced these X-rays, and what impact did this radiation have on the intergalactic medium long ago?The First BinariesA team of scientists led by Hao Xu (UC San Diego) has suggested that the very first generation of stars might be an important contributor to these X-rays.This hypothetical first generation, Population III stars, are thought to have formed before and during reionization from large clouds of gas containing virtually no metals. Studies suggest that a large fraction of Pop III stars formed in binaries and when those stars ended their lives as black holes, ensuing accretion from their companions could produceX-ray radiation.The evolution with redshift of the mean X-ray background intensities. Each curve represents a different

  9. Toward Adaptive X-Ray Telescopes

    Science.gov (United States)

    O'Dell, Stephen L.; Atkins, Carolyn; Button, Tim W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peer; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.; Kolodziejczak, Jeffrey J.; hide

    2011-01-01

    Future x-ray observatories will require high-resolution (less than 1 inch) optics with very-large-aperture (greater than 25 square meter) areas. Even with the next generation of heavy-lift launch vehicles, launch-mass constraints and aperture-area requirements will limit the surface areal density of the grazing-incidence mirrors to about 1 kilogram per square meter or less. Achieving sub-arcsecond x-ray imaging with such lightweight mirrors will require excellent mirror surfaces, precise and stable alignment, and exceptional stiffness or deformation compensation. Attaining and maintaining alignment and figure control will likely involve adaptive (in-space adjustable) x-ray optics. In contrast with infrared and visible astronomy, adaptive optics for x-ray astronomy is in its infancy. In the middle of the past decade, two efforts began to advance technologies for adaptive x-ray telescopes: The Generation-X (Gen-X) concept studies in the United States, and the Smart X-ray Optics (SXO) Basic Technology project in the United Kingdom. This paper discusses relevant technological issues and summarizes progress toward adaptive x-ray telescopes.

  10. Multiple beam x-ray diffraction tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kewish, C.M.; Davis, J.R.; Coyle, R.A. [Monash University, Clayton, VIC (Australia). Department of Physics

    1999-12-01

    Full text: X-ray diffraction computed tomography (XDT) is an imaging modality that utilises scattered x-rays to reconstruct an image. Since its inception in 1985, various detection scenarios and imaging techniques have been developed to demonstrate the accuracy and applicability of XDT. Many of the previous methods for measuring the scattered x-rays from an object utilise detectors that accept x-rays scattered from the entire length of the raypath through the object. The detector apertures must therefore have dimensions similar to the largest width of the scanned object. This creates a situation where the detected x-rays are not derived from a single scattering angle. A new method of scanning the x-rays scattered from an object is presented which allows quantitative determination of the spatial distribution of differential scattering cross section within a cross-sectional plane of the object. The new method incorporates a position sensitive detector and an arrangement of Soller slits. The acquired data represents both spatial and angular information. For each raypath through the object, a partial diffraction projection is measured at the off-axis detector and a set of diffraction projections is assembled by combining the diffracted signal from all rays through the object. A reconstruction strategy that accounts for attenuation of the primary beam and the scattered beam allows us to reconstruct a map of the differential scattering cross section in the sample for a given angle. Copyright (1999) Australian X-ray Analytical Association Inc. 3 refs.

  11. X- rays and matter- the basic interactions

    DEFF Research Database (Denmark)

    Als-Nielsen, Jens

    2008-01-01

    In this introductory article we attempt to provide the theoretical basis for developing the interaction between X-rays and matter, so that one can unravel properties of matter by interpretation of X-ray experiments on samples. We emphasize that we are dealing with the basics, which means that we...... shall limit ourselves to a discussion of the interaction of an X-ray photon with an isolated atom, or rather with a single electron in a Hartree-Fock atom. Subsequent articles in this issue deal with more complicated - and interesting - forms of matter encompassing many atoms or molecules. To cite...

  12. X-ray Emission from Millisecond Pulsars

    Science.gov (United States)

    Zavlin, Vyacheslav

    2006-01-01

    Isolated (solitary or non-accreting) millisecond pulsars with observed X-ray emission can be divided in two distinct groups: those emitting nonthermal (magnetospheric) radiation and pulsars with the bulk of X-rays of a thermal origin, presumably emitted from small hot spots around the magnetic poles on the neutron star surface (polar caps). I will discuss properties of X-ray emission detected with Chandra and XMM-Newton from a number of millisecond pulsars, with emphasis on those of the thermal component, and compare them with predictions of radio pulsar models.

  13. Two-dimensional x-ray diffraction

    CERN Document Server

    He, Bob B

    2009-01-01

    Written by one of the pioneers of 2D X-Ray Diffraction, this useful guide covers the fundamentals, experimental methods and applications of two-dimensional x-ray diffraction, including geometry convention, x-ray source and optics, two-dimensional detectors, diffraction data interpretation, and configurations for various applications, such as phase identification, texture, stress, microstructure analysis, crystallinity, thin film analysis and combinatorial screening. Experimental examples in materials research, pharmaceuticals, and forensics are also given. This presents a key resource to resea

  14. Materials for refractive x-ray optics.

    Science.gov (United States)

    Lund, M W

    1997-01-01

    An X-ray lens using refraction has been proposed by Tomie, and demonstrated for 14 keV X-rays by Snigirev et al. This type of lens is made from a series of very weak lens elements. I calculate the properties of such lenses constructed of various chemical elements and compounds over the range of 1 to 30 keV. In general, I find that X-ray optics made from low density, low Z materials have the widest useful apertures, but require more lens elements than denser and higher Z materials.

  15. The Future of X-Ray Optics

    Science.gov (United States)

    Weisskopf, Martin C.

    2013-01-01

    The most important next step is the development of X-ray optics comparable to (or better than) Chandra in angular resolution that far exceed Chandra s effective area. Use the long delay to establish an adequately funded, competitive technology program along the lines I have recommended. Don't be diverted from this objective, except for Explorer-class missions. Progress in X-ray optics, with emphasis on the angular resolution, is central to the paradigm-shifting discoveries and the contributions of X-ray astronomy to multiwavelength astrophysics over the past 51 years.

  16. The ROSAT X-ray Background Dipole

    OpenAIRE

    Plionis, M.; Georgantopoulos, I.

    1998-01-01

    We estimate the dipole of the diffuse 1.5 keV X-ray background from the ROSAT all-sky survey map of Snowden et al (1995). We first subtract the diffuse Galactic emission by fitting to the data an exponential scale height, finite radius, disk model. We further exclude regions of low galactic latitudes, of local X-ray emission (eg the North Polar Spur) and model them using two different methods. We find that the ROSAT X-ray background (XRB) dipole points towards $(l,b) ~ (288, 25) \\pm 19 degree...

  17. Two methods for studying the X-ray variability

    NARCIS (Netherlands)

    Yan, Shu-Ping; Ji, Li; Méndez, Mariano; Wang, Na; Liu, Siming; Li, Xiang-Dong

    2016-01-01

    The X-ray aperiodic variability and quasi-periodic oscillation (QPO) are the important tools to study the structure of the accretion flow of X-ray binaries. However, the origin of the complex X-ray variability from X-ray binaries remains yet unsolved. We proposed two methods for studying the X-ray

  18. Settling time of dental x-ray tube head after positioning

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Suk Ja; Kang, Byung Cheol [Department of Oral and Maxillofacial Radiology, Chonnam National University, Gwangju (Korea, Republic of); Wang, Se Myung; Koh, Chang Sung [Department of Mechatronics, Kwangju Institute of Science and Technology, Gwangju (Korea, Republic of)

    2002-09-15

    The aim of this study was to introduce a method of obtaining the oscillation graphs of the dental x-ray tube heads relative to time using an accelerometer. An Accelerometer, Piezotron type 8704B25 (Kistler Instrument Co., Amherst, NY, USA) was utilized to measure the horizontal oscillation of the x-ray tube head immediately after positioning the tube head for an intraoral radiograph. The signal from the sensor was transferred to a dynamic signal analyzer, which displayed the magnitude of the acceleration on the Y-axis and time lapse on the X-axis. The horizontal oscillation of the tube head was measured relative to time, and the settling time was also determined on the basis of the acceleration graphs for 6 wall type, 5 floor-fixed type, and 4 mobile type dental x-ray machines. The oscillation graphs showed that tube head movement decreased rapidly over time. The settling time varied with x-ray machine types. Wall-type x-ray machines had a settling time of up to 6 seconds, 5 seconds for fixed floor-types, and 11 seconds for the mobile-types. Using an accelerometer, we obtained the oscillation graphs of the dental x-ray tube head relative to time. The oscillation graph with time can guide the operator to decide upon the optimum exposure moment after xray tube head positioning for better radiographic resolution.

  19. Insights from soft X-rays

    DEFF Research Database (Denmark)

    Raaf, Jennifer; Issinger, Olaf-Georg; Niefind, Karsten

    2008-01-01

    The diffraction pattern of a protein crystal is normally a product of the interference of electromagnetic waves scattered by electrons of the crystalline sample. The diffraction pattern undergoes systematic changes in case additionally X-ray absorption occurs, meaning if the wavelength of the pri......The diffraction pattern of a protein crystal is normally a product of the interference of electromagnetic waves scattered by electrons of the crystalline sample. The diffraction pattern undergoes systematic changes in case additionally X-ray absorption occurs, meaning if the wavelength...... of the primary X-ray beam is relatively close to the absorption edge of selected elements of the sample. The resulting effects are summarized as "anomalous dispersion" and can be always observed with "soft" X-rays (wavelength around 2 A) since they match the absorption edges of sulfur and chlorine...

  20. Demonstration of X-ray talbot interferometry

    CERN Document Server

    Momose, A; Kawamoto, S; Hamaishi, Y; Takai, K; Suzuki, Y

    2003-01-01

    First Talbot interferometry in the hard X-ray region was demonstrated using a pair of transmission gratings made by forming gold stripes on glass plates. By aligning the gratings on the optical axis of X-rays with a separation that caused the Talbot effect by the first grating, moire fringes were produced inclining one grating slightly against the other around the optical axis. A phase object placed in front of the first grating was detected by moire-fringe bending. Using the technique of phase-shifting interferometry, the differential phase corresponding to the phase object could also be measured. This result suggests that X-ray Talbot interferometry is a novel and simple method for phase-sensitive X-ray radiography. (author)

  1. Center for X-ray Optics (CXRO)

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for X-Ray Optics at Lawrence Berkeley National Laboratory works to further science and technology using short wavelength optical systems and techniques....

  2. Chest X-Ray (Chest Radiography)

    Science.gov (United States)

    ... Lung tissue absorbs little radiation and will appear dark on the image. Until recently, x-ray images ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  3. Microfabrication of hard x-ray lenses

    DEFF Research Database (Denmark)

    Stöhr, Frederik

    This thesis deals with the development of silicon compound refractive lenses (Si-CRLs) for shaping hard x-ray beams. The CRLs are to be fabricated using state of the art microfabrication techniques. The primary goal of the thesis work is to produce Si-CRLs with considerably increased structure...... developed. Inverse replica molding in PDMS of the CRLs was established as an effective way to circumvent the limitations AFM probes have when concave surfaces need to be characterized, e.g. due to the finite lengths of AFM probes. Four different x-ray optical components have been designed, manufactured...... of space for sample surroundings and ensure low-divergent and wide x-ray beams with narrow waists. Both results are substantial improvements to what was available at the start of this thesis work. The challenge of making x-ray objectives in silicon by interdigitation of lenslets alternately focusing...

  4. X-ray Optics Development at MSFC

    Science.gov (United States)

    Sharma, Dharma P.

    2017-01-01

    Development of high resolution focusing telescopes has led to a tremendous leap in sensitivity, revolutionizing observational X-ray astronomy. High sensitivity and high spatial resolution X-ray observations have been possible due to use of grazing incidence optics (paraboloid/hyperboloid) coupled with high spatial resolution and high efficiency detectors/imagers. The best X-ray telescope flown so far is mounted onboard Chandra observatory launched on July 23,1999. The telescope has a spatial resolution of 0.5 arc seconds with compatible imaging instruments in the energy range of 0.1 to 10 keV. The Chandra observatory has been responsible for a large number of discoveries and has provided X-ray insights on a large number of celestial objects including stars, supernova remnants, pulsars, magnetars, black holes, active galactic nuclei, galaxies, clusters and our own solar system.

  5. Silicon Wafer X-ray Mirror Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this one year research project, we propose to do the following four tasks; (1) Design the silicon wafer X-ray mirror demo unit and develop a ray-tracing code to...

  6. Tuberculosis, advanced - chest x-rays (image)

    Science.gov (United States)

    Tuberculosis is an infectious disease that causes inflammation, the formation of tubercules and other growths within tissue, ... death. These chest x-rays show advanced pulmonary tuberculosis. There are multiple light areas (opacities) of varying ...

  7. Nonrelativistic quantum X-ray physics

    CERN Document Server

    Hau-Riege, Stefan P

    2015-01-01

    Providing a solid theoretical background in photon-matter interaction, Nonrelativistic Quantum X-Ray Physics enables readers to understand experiments performed at XFEL-facilities and x-ray synchrotrons. As a result, after reading this book, scientists and students will be able to outline and perform calculations of some important x-ray-matter interaction processes. Key features of the contents are that the scope reaches beyond the dipole approximation when necessary and that it includes short-pulse interactions. To aid the reader in this transition, some relevant examples are discussed in detail, while non-relativistic quantum electrodynamics help readers to obtain an in-depth understanding of the formalisms and processes. The text presupposes a basic (undergraduate-level) understanding of mechanics, electrodynamics, and quantum mechanics. However, more specialized concepts in these fields are introduced and the reader is directed to appropriate references. While primarily benefiting users of x-ray light-sou...

  8. Experimental X-Ray Ghost Imaging.

    Science.gov (United States)

    Pelliccia, Daniele; Rack, Alexander; Scheel, Mario; Cantelli, Valentina; Paganin, David M

    2016-09-09

    We report an experimental proof of principle for ghost imaging in the hard-x-ray energy range. We use a synchrotron x-ray beam that is split using a thin crystal in Laue diffraction geometry. With an ultrafast imaging camera, we are able to image x rays generated by isolated electron bunches. At this time scale, the shot noise of the synchrotron emission process is measurable as speckles, leading to speckle correlation between the two beams. The integrated transmitted intensity from a sample located in the first beam is correlated with the spatially resolved intensity measured in the second, empty, beam to retrieve the shadow of the sample. The demonstration of ghost imaging with hard x rays may open the way to protocols to reduce radiation damage in medical imaging and in nondestructive structural characterization using free electron lasers.

  9. X-ray induced optical reflectivity

    Directory of Open Access Journals (Sweden)

    Stephen M. Durbin

    2012-12-01

    Full Text Available The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity. Optical absorption associated with band filling and band gap narrowing is shown to explain the basic features found in recent measurements on an insulator (silicon nitride, Si3N4, a semiconductor (gallium arsenide, GaAs, and a metal (gold, Au, obtained with ∼100 fs x-ray pulses at 500-2000 eV and probed with 800 nm laser pulses. In particular GaAs exhibits an abrupt drop in reflectivity, persisting only for a time comparable to the x-ray excitation pulse duration, consistent with prompt band gap narrowing.

  10. Milli X-Ray Fluorescence Spectrometer

    Data.gov (United States)

    Federal Laboratory Consortium — The Eagle III Micro XRF unit is similar to a traditional XRF unit, with the primary difference being that the X-rays are focused by a polycapillary optic into a spot...

  11. Silicon Wafer X-ray Mirror Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this one year research project, we propose to do the following four tasks;(1) Design the silicon wafer X-ray mirror demo unit and develop a ray-tracing code to...

  12. Quantum optics with X-rays

    Science.gov (United States)

    Kuznetsova, Elena; Kocharovskaya, Olga

    2017-11-01

    The demonstration of strong coupling between two nuclear polariton modes in the X-ray spectral region using two coupled cavities each containing a thin layer of iron brings new opportunities for exploring quantum science.

  13. X-ray diffraction contrast tomography (DCT) system, and an X-ray diffraction contrast tomography (DCT) method

    DEFF Research Database (Denmark)

    2012-01-01

    Source: US2012008736A An X-ray diffraction contrast tomography system (DCT) comprising a laboratory X-ray source (2), a staging device (5) rotating a polycrystalline material sample in the direct path of the X-ray beam, a first X-ray detector (6) detecting the direct X-ray beam being transmitted...

  14. Linking Jet Emission, X-Ray States, and Hard X-Ray Tails in the Neutron Star X-Ray Binary GX 17+2

    NARCIS (Netherlands)

    Migliari, S.; Miller-Jones, J.C.A.; Fender, R.P.; Homan, J.; di Salvo, T.; Rothschild, R.E.; Rupen, M.P.; Tomsick, J.A.; Wijnands, R.; van der Klis, M.

    2007-01-01

    We present the results of simultaneous radio (VLA) and X-ray (RXTE) observations of the Z-type neutron star X-ray binary GX 17+2. The aim is to assess the coupling between X-ray and radio properties throughout its three rapidly variable X-ray states and during the time-resolved transitions. These

  15. Capacitor discharges, magnetohydrodynamics, X-rays, ultrasonics

    CERN Document Server

    Früngel, Frank B A

    1965-01-01

    High Speed Pulse Technology, Volume 1: Capacitor Discharges - Magnetohydrodynamics - X-Rays - Ultrasonics deals with the theoretical and engineering problems that arise in the capacitor discharge technique.This book discusses the characteristics of dielectric material, symmetrical switch tubes with mercury filling, and compensation conductor forms. The transformed discharge for highest current peaks, ignition transformer for internal combustion engines, and X-ray irradiation of subjects in mechanical motion are also elaborated. This text likewise covers the transformed capacitor discharge in w

  16. Parametric X-rays at FAST

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Tanaji [Fermilab

    2016-06-01

    We discuss the generation of parametric X-rays (PXR) in the photoinjector at the new FAST facility at Fermilab. Detailed calculations of the intensity spectrum, energy and angular widths and spectral brilliance with a diamond crystal are presented. We also report on expected results with PXR generated while the beam is channeling. The low emittance electron beam makes this facility a promising source for creating brilliant X-rays.

  17. Nanofocusing Refractive X-Ray Lenses

    OpenAIRE

    Boye, Pit

    2010-01-01

    This thesis is concerned with the optimization and development of the production of nanofocusing refractive x-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution x-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. ...

  18. Lacquer polishing of x-ray optics.

    Science.gov (United States)

    Catura, R C; Joki, E G; Roethig, D T; Brookover, W J

    1987-04-15

    Techniques for polishing figured x-ray optics by a lacquer-coating process are described. This acrylic lacquer coating has been applied with an optical quality of an eighth wave in red light and very effectively covers surface roughness with spatial wavelengths less than ~0.2 mm. Tungsten films have been deposited on the lacquer coatings to provide highly efficient x-ray reflectivity.

  19. X-Ray Emission from Compact Sources

    Energy Technology Data Exchange (ETDEWEB)

    Cominsky, L

    2004-03-23

    This paper presents a review of the physical parameters of neutron stars and black holes that have been derived from X-ray observations. I then explain how these physical parameters can be used to learn about the extreme conditions occurring in regions of strong gravity, and present some recent evidence for relativistic effects seen in these systems. A glossary of commonly used terms and a short tutorial on the names of X-ray sources are also included.

  20. Monochromatic Mammographic Imaging Using X-ray Polycapillary Optics

    National Research Council Canada - National Science Library

    Sugiro, Francisca

    2000-01-01

    .... Monochromatic x rays can be used to produce higher contrast images. Polycapillary x-ray optics technology can produce a highly parallel, monochromatic, x-ray beam from a conventional radiographic source...

  1. Optics Developments for X-Ray Astronomy

    Science.gov (United States)

    Ramsey, Brian

    2014-01-01

    X-ray optics has revolutionized x-ray astronomy. The degree of background suppression that these afford, have led to a tremendous increase in sensitivity. The current Chandra observatory has the same collecting area (approx. 10(exp 3)sq cm) as the non-imaging UHURU observatory, the first x-ray observatory which launched in 1970, but has 5 orders of magnitude more sensitivity due to its focusing optics. In addition, its 0.5 arcsec angular resolution has revealed a wealth of structure in many cosmic x-ray sources. The Chandra observatory achieved its resolution by using relatively thick pieces of Zerodur glass, which were meticulously figured and polished to form the four-shell nested array. The resulting optical assembly weighed around 1600 kg, and cost approximately $0.5B. The challenge for future x-ray astronomy missions is to greatly increase the collecting area (by one or more orders of magnitude) while maintaining high angular resolution, and all within realistic mass and budget constraints. A review of the current status of US optics for x-ray astronomy will be provided along with the challenges for future developments.

  2. X-ray emission from normal stars

    Science.gov (United States)

    Rosner, Robert

    1990-01-01

    The paper addresses the potential for future X-ray missions to determine the fundamental cause of stellar X-ray emissions based on available results and existing analyses. The determinants of stellar X-ray emission are listed, and the relation of stellar X-ray emissions to the 'universal' activity-rotation connection is discussed. The specific rotation-activity connection for evolved stars is mentioned, and the 'decay' of stellar activity at the low-mass end of the main sequence is related to observational data. The data from Einstein and EXOSAT missions that correspond to these issues are found to be sparse, and more observational work is found to be necessary. Also, it is concluded that some issues need to be addressed, such as the X-ray dividing line in evolved stars and the absence of X-ray emission from dA stars. The related observational requirements and instrumental capabilities are given for each significant research focus.

  3. X-ray Studies of Planetary Nebulae

    Science.gov (United States)

    Montez, Rodolfo

    2017-10-01

    X-ray emission from planetary nebulae (PNe) provides unique insight on the formation and evolution of PNe. Past observations and the ongoing Chandra Planetary Nebulae Survey (ChanPlaNS) provide a consensus on the two types of X-ray emission detected from PNe: extended and compact point-like sources. Extended X-ray emission arises from a shocked ``hot bubble'' plasma that resides within the nebular shell. Cooler than expected hot bubble plasma temperatures spurred a number of potential solutions with one emerging as the likely dominate process. The origin of X-ray emission from compact sources at the location of the central star is less clear. These sources might arise from one or combinations of the following processes: self-shocking stellar winds, spun-up binary companions, and/or accretion, perhaps from mass transfer, PN fallback, or debris disks. In the discovery phase, X-ray studies of PNe have mainly focused on the origin of the various emission processes. New directions incorporate multi-wavelength observations to study the influence of X-ray emission on the rest of the electromagnetic spectrum.

  4. The universe in X-rays

    CERN Document Server

    Hasinger, Günther

    2008-01-01

    In the last 45 years, X-ray astronomy has become an integral part of modern astrophysics and cosmology. There is a wide range of astrophysical objects and phenomena, where X-rays provide crucial diagnostics. In particular they are well suited to study hot plasmas and matter under extreme physical conditions in compact objects. This book summarizes the present status of X-ray astronomy in terms of observational results and their astrophysical interpretation. It is written for students, astrophysicists as well a growing community of physicists interested in the field. An introduction including historical material is followed by chapters on X-ray astronomical instrumentation. The next two parts summarize in 17 chapters the present knowledge on various classes of X-ray sources in the galactic and extragalactic realm. While the X-ray astronomical highlights discussed in this book are mainly based on results from ROSAT, ASCA, RXTE, BeppoSAX, Chandra and XMM-Newton, a final chapter provides an outlook on observation...

  5. X-rays as a probe of the Universe

    Indian Academy of Sciences (India)

    Table of contents. X-rays as a probe of the Universe · Probing the Universe ….. Flux = sT4 umax = 1011 T (in Kelvin) · History of x-ray astronomy · X-ray Production · X-ray spectra · Celestial sphere as seen by UHURU (1970) · Slide 8 · X-rays from accreting binary systems · Slide 10 · Neutron stars: Black Hole: · Primary X-ray ...

  6. [X-ray hardening correction for ICT in testing workpiece].

    Science.gov (United States)

    Peng, Guang-han; Cai, Xin-hua; Han, Zhong; Yang, Xue-heng

    2008-06-01

    Since energy spectrum of X-ray is polychromatic source in X-ray industrial computerized tomography, the variation of attenuation coefficient with energy leads to the lower energy of X-ray radiation being absorbed preferentially when X-ray is transmitting the materials. And the higher the energy of X-ray, the lower the attenuation coefficient of X-ray. With the increase in the X-ray transmission thickness, it becomes easier for the X-ray to transmit the matter. Thus, the phenomenon of energy spectrum hardening of X-ray takes place, resulting from the interaction between X-ray and the materials. This results in false images in the reconstruction of X-ray industrial computerized tomography. Therefore, hardening correction of energy spectrum of X-ray has to be done. In the present paper, not only is the hardening phenomenon of X-ray transmitting the materials analyzed, but also the relation between the X-ray beam sum and the transmission thickness of X-ray is discussed. And according to the Beer law and the characteristics of interaction when X-ray is transmitting material, and by getting the data of X-ray beam sum, the relation equation is fitted between the X-ray beam sum and X-ray transmission thickness. Then, the relation and the method of equivalence are carried out for X-ray beam sum being corrected. Finally, the equivalent and monochromatic attenuation coefficient fitted value for X-ray transmitting the material is reasoned out. The attenuation coefficient fitted value is used for product back-projection image reconstruction in X-ray industrial computerized tomography. Thus, the effect caused by X-ray beam hardening is wiped off effectively in X-ray industrial computerized tomography.

  7. Fabrication of large area X-ray diffraction grating for X-ray phase imaging

    Science.gov (United States)

    Noda, Daiji; Tokuoka, Atsushi; Katori, Megumi; Minamiyama, Yasuto; Yamashita, Kenji; Nishida, Satoshi; Hattori, Tadashi

    2012-07-01

    X-ray lithography, which uses highly directional synchrotron radiation, is one of the technologies that can be used for fabricating micrometer-sized structures. In X-ray lithography, the accuracy of the fabricated structure depends largely on the accuracy of the X-ray mask. Since X-ray radiation is highly directional, a micro-fabrication technology that produces un-tapered and high aspect ratio highly absorbent structures on a low absorbent membrane is required. Conventionally, a resin material is used as the support membrane for large area X-ray masks. However, resin membranes have the disadvantage that they can sag after several cycles of X-ray exposure due to the heat generated by the X-rays. Therefore, we proposed and used thin carbon wafers for the membrane material because carbon has an extremely small thermal expansion coefficient. We fabricated new carbon membrane X-ray masks, and these results of X-ray lithography demonstrate the superior performance.

  8. Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free Electron Laser

    DEFF Research Database (Denmark)

    Lemke, Henrik T.; Bressler, Christian; Chen, Lin X.

    2013-01-01

    X-ray free electron lasers (XFELs) deliver short (hard X-rays, making them excellent sources for time-resolved studies. Here we show that, despite the inherent instabilities of current (SASE based) XFELs, they can be used for measuring high......-quality X-ray absorption data and we report femtosecond time-resolved X-ray absorption near-edge spectroscopy (XANES) measurements of a spin-crossover system, iron(II) tris(2,2'-bipyridine) in water. The data indicate that the low-spin to high-spin transition can be modeled by single-exponential kinetics...

  9. Dual Energy X-Ray CT by Compton Scattering Hard X-Ray Source

    CERN Document Server

    Uesaka, Mitsuru; Kaneyasu, Tatsuo; Torikoshi, Masami

    2005-01-01

    We have developed a compact Compton scattering hard X-ray source at Nuclear Engineering Research Laboratory, University of Tokyo. The compact hard X-ray source can produce tunable monochromatic hard X-rays. The monochromatic hard X-rays are required in large field of medical and biological applications. We are planning to perform dual-energy X-ray CT, which enables us to measure atomic number Z distribution and electron density re distribution in a material. The hard X-ray source has an advantage to perform dual-energy X-ray CT. The X-ray energy can be changed quickly by introducing a fundamental frequency and a second harmonic frequency lasers. This quick energy change is indispensable to medical imaging and very difficult in a large SR light source and others. The information on the atomic number and electron density will be used for treatment plan in radiotherapy as well as for identification of materials in a nondestructive test. We examined applicability of the dual-energy X-ray CT for atomic number meas...

  10. Ultrafast x-ray-induced nuclear dynamics in diatomic molecules using femtosecond x-ray-pump–x-ray-probe spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, C. S.; Picón, A.; Bostedt, C.; Rudenko, A.; Marinelli, A.; Moonshiram, D.; Osipov, T.; Rolles, D.; Berrah, N.; Bomme, C.; Bucher, M.; Doumy, G.; Erk, B.; Ferguson, K. R.; Gorkhover, T.; Ho, P. J.; Kanter, E. P.; Krässig, B.; Krzywinski, J.; Lutman, A. A.; March, A. M.; Ray, D.; Young, L.; Pratt, S. T.; Southworth, S. H.

    2016-07-01

    The availability at x-ray free electron lasers of generating two intense, femtosecond x-ray pulses with controlled time delay opens the possibility of performing time-resolved experiments for x-ray induced phenomena. We have applied this capability to molecular dynamics. In diatomic molecules composed of low-Z elements, K-shell ionization creates a core-hole state in which the main decay is an Auger process involving two electrons in the valence shell. After Auger decay, the nuclear wavepackets of the transient two-valence-hole states continue evolving on the femtosecond timescale, leading either to separated atomic ions or long-lived quasi-bound states. By using an x-ray pump and an x-ray probe pulse tuned above the K-shell ionization threshold of the nitrogen molecule, we are able to observe ion dissociation in progress by measuring the time-dependent kinetic energy releases of different breakup channels. We simulated the measurements on N2 with a molecular dynamics model that accounts for K-shell ionization, Auger decay, and time evolution of the nuclear wavepackets. In addition to explaining the time-dependent feature in the measured kinetic energy release distributions from the dissociative states, the simulation also reveals the contributions of quasi-bound states.

  11. Flash X-Ray Generator At High Energy: GREC

    Science.gov (United States)

    Buchet, J.; Biero, H.; Fourrier, G.

    1983-08-01

    GREC, an acronym for "Generateur de Radiographie EClair" was designed for visualisation, measurements and studies on dynamic behavior of materials under high explosive loading. GREC was built in 1974 by Physics International for the CEA. Since the first operating time, 1975, this facility has been improving, taking advantage of progress in the techniques involved, especialy focusing and transport of intense electron beams. In this paper, we describe the X-ray machine and give some details on the image detection device. The pulse generator, a 80 stages Marx Generator can deliver a peak voltage of 9 MV in 1.2/us by series erection of 2 x 80 capacitors charged at + 60 kV. The Hulse-forming network, a tri-axial Blumlein, delivers a 80 ns-pulse via a 26 ohms impedance transmission line to the transport section. This transport section is a 24 cm diameter, 2 meters long, magnetic-insulated coaxial line. At the end, the X-ray radiation is emitted by bremstrahlung of the electrons impinging the tantalum anode of the dis-charge diode. The main specifications are : - electrical : 7 -MV - 180 kA - 30 ns - X-ray : Diode 1 : 400 R at 1 meter ; spot size : 20 mm Diode 2 : 100 - 300 R at 1 meter ; spot size : 4-8 mm The image acouisition device has been designed for X-raying of objects under loading of un to 50 kg of high explosives. In the paper, we give some details on the exnerimental arrangement used. Despite the severe environmental shock constraints, reasonable measurements of line-integrated density are possible.

  12. Handbook of X-Ray Astronomy

    Science.gov (United States)

    Arnaud, Keith A. (Editor); Smith, Randall K.; Siemiginowska, Aneta

    2011-01-01

    X-ray astronomy was born in the aftermath of World War II as military rockets were repurposed to lift radiation detectors above the atmosphere for a few minutes at a time. These early flights detected and studied X-ray emission from the Solar corona. The first sources beyond the Solar System were detected during a rocket flight in 1962 by a team headed by Riccardo Giaccom at American Science and Engineering, a company founded by physicists from MIT. The rocket used Geiger counters with a system designed to reduce non-X-ray backgrounds and collimators limiting the region of sky seen by the counters. As the rocket spun, the field of view (FOV) happened to pass over what was later found to be the brightest non-Solar X-ray source; later designated See X-1. It also detected a uniform background glow which could not be resolved into individual sources. A follow-up campaign using X-ray detectors with better spatial resolution and optical telescopes identified See X-1 as an interacting binary with a compact (neutron star) primary. This success led to further suborbital rocket flights by a number of groups. More X-ray binaries were discovered, as well as X-ray emission from supernova remnants, the radio galaxies M87 and Cygnus-A, and the Coma cluster. Detectors were improved and Geiger counters were replaced by proportional counters, which provided information about energy spectra of the sources. A constant challenge was determining precise positions of sources as only collimators were available.

  13. X-Ray Point-source Populations Constituting the Galactic Ridge X-Ray Emission

    Science.gov (United States)

    Morihana, Kumiko; Tsujimoto, Masahiro; Yoshida, Tessei; Ebisawa, Ken

    2013-03-01

    Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of X-ray astronomy; this is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray observations have shown that numerous X-ray point sources account for a large fraction of the GRXE in the hard band (2-8 keV). However, the nature of these sources is poorly understood. Using the deepest X-ray observations made in the Chandra bulge field, we present the result of a coherent photometric and spectroscopic analysis of individual X-ray point sources for the purpose of constraining their nature and deriving their fractional contributions to the hard-band continuum and Fe K line emission of the GRXE. Based on the X-ray color-color diagram, we divided the point sources into three groups: A (hard), B (soft and broad spectrum), and C (soft and peaked spectrum). The group A sources are further decomposed spectrally into thermal and non-thermal sources with different fractions in different flux ranges. From their X-ray properties, we speculate that the group A non-thermal sources are mostly active galactic nuclei and the thermal sources are mostly white dwarf (WD) binaries such as magnetic and non-magnetic cataclysmic variables (CVs), pre-CVs, and symbiotic stars, whereas the group B and C sources are X-ray active stars in flares and quiescence, respectively. In the log N-log S curve of the 2-8 keV band, the group A non-thermal sources are dominant above ≈10-14 erg cm-2 s-1, which is gradually taken over by Galactic sources in the fainter flux ranges. The Fe Kα emission is mostly from the group A thermal (WD binaries) and the group B (X-ray active stars) sources.

  14. X-Ray Calorimeter Arrays for Astrophysics

    Science.gov (United States)

    Kilbourne, Caroline A.

    2009-01-01

    High-resolution x-ray spectroscopy is a powerful tool for studying the evolving universe. The grating spectrometers on the XMM and Chandra satellites started a new era in x-ray astronomy, but there remains a need for instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band (around 6 keV) and can enable imaging spectroscopy of extended sources, such as supernova remnants and galaxy clusters. The instrumentation needed is a broad-band imaging spectrometer - basically an x-ray camera that can distinguish tens of thousands of x-ray colors. The potential benefits to astrophysics of using a low-temperature calorimeter to determine the energy of an incident x-ray photon via measurement of a small change in temperature was first articulated by S. H. Moseley over two decades ago. In the time since, technological progress has been steady, though full realization in an orbiting x-ray telescope is still awaited. A low-temperature calorimeter can be characterized by the type of thermometer it uses, and three types presently dominate the field. The first two types are temperature-sensitive resistors - semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a paramagnetic thermometer. These types can be considered the three generations of x-ray calorimeters; by now each has demonstrated a resolving power of 2000 at 6 keV, but only a semiconductor calorimeter system has been developed to spaceflight readiness. The Soft X-ray Spectrometer on Astro-H, expected to launch in 2013, will use an array of silicon thermistors with I-IgTe x-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays, kilo-pixel arrays of the superconducting calorimeters are just now being produced, and it is anticipated that much larger arrays will require the non-dissipative advantage of magnetic thermometers.

  15. Radiation exposure during chest X-ray examinations in a premature intensive care unit: phantom studies

    Energy Technology Data Exchange (ETDEWEB)

    Duetting, T.; Foerste, B.; Darge, K.; Troeger, J. [Heidelberg Univ. (Germany). Dept. of Paediatric Radiology; Knoch, T. [Heidelberg Univ. (Germany). Central Radiation Protection

    1999-03-01

    Background. There are few reports on the radiation dose received by infants, their family and radiographers exposed to scatter radiation in a premature baby intensive care unit. Objective. To evaluate the degree of radiation exposure from diagnostic X-ray examinations with mobile X-ray machines in a premature intensive care unit. Materials and methods. The radiation exposure of an adjacent newborn, the radiographer and other persons in the room was simulated using phantoms during X-ray examination of the chest using vertical and horizontal beams. Results. Most of the measured doses were below the registration limit of the measuring apparatus and had to be extrapolated by multiple exposures. Without exception, the maximal doses were significantly lower than the permitted limit for persons not professionally exposed to X-rays. Conclusions. Recommendations to avoid unnecessary radiation exposure are given. (orig.) With 2 figs., 3 tabs., 10 refs.

  16. X-ray detectors for digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yaffe, M.J.; Rowlands, J.A. [Imaging Research Program, Sunnybrook Health Science Centre, University of Toronto, Toronto, ON (Canada)

    1997-01-01

    Digital radiography offers the potential of improved image quality as well as providing opportunities for advances in medical image management, computer-aided diagnosis and teleradiology. Image quality is intimately inked to the precise and accurate acquisition of information from the x-ray beam transmitted by the patient, i.e. to the performance of the x-ray detector. Detectors for digital radiography must meet the needs of the specific radiological procedure where they will be used. Key parameters are partial resolution, uniformity of response, contrast sensitivity, dynamic range, acquisition speed and frame rate. The underlying physical considerations defining the performance of x-ray detectors for radiography will be reviewed. Some of the more promising existing and experimental detector technologies which may be suitable for digital radiography will be considered. Devices that can be employed in full-area detectors and also those more appropriate for scanning x-ray systems will be discussed. These include various approaches based on phosphor x-ray converters, where light quanta are produced as an intermediate stage, as well as direct -ray-to-charge conversion materials such as zinc cadmium telluride, amorphous selenium and crystalline silicon. (author)

  17. X-ray optics of gold nanoparticles.

    Science.gov (United States)

    Letfullin, Renat R; Rice, Colin E W; George, Thomas F

    2014-11-01

    Gold nanoparticles have been investigated as contrast agents for traditional x-ray medical procedures, utilizing the strong absorption characteristics of the nanoparticles to enhance the contrast of the detected x-ray image. Here we use the Kramers-Kronig relation for complex atomic scattering factors to find the real and imaginary parts of the index of refraction for the medium composed of single-element materials or compounds in the x-ray range of the spectrum. These complex index of refraction values are then plugged into a Lorenz-Mie theory to calculate the absorption efficiency of various size gold nanoparticles for photon energies in the 1-100 keV range. Since the output from most medical diagnostic x-ray devices follows a wide and filtered spectrum of photon energies, we introduce and compute the effective intensity-absorption-efficiency values for gold nanoparticles of radii varying from 5 to 50 nm, where we use the TASMIP model to integrate over all spectral energies generated by typical tungsten anode x-ray tubes with kilovolt potentials ranging from 50 to 150 kVp.

  18. X-ray spectroscopy an introduction

    CERN Document Server

    Agarwal, Bipin K

    1979-01-01

    Rontgen's discovery of X-rays in 1895 launched a subject which became central to the development of modern physics. The verification of many of the predic­ tions of quantum theory by X-ray spectroscopy in the early part of the twen­ tieth century stimulated great interest in thi's area, which has subsequently influenced fields as diverse as chemical physics, nuclear physics, and the study of the electronic properties of solids, and led to the development of techniques such as Auger, Raman, and X-ray photoelectron spectroscopy. The improvement of the theoretical understanding of the physics underlying X-ray spectroscopy has been accompanied by advances in experimental techniques, and the subject provides an instructive example of how progress on both these fronts can be mutually beneficial. This book strikes a balance between his­ torical description, which illustrates this symbiosis, and the discussion of new developments. The application of X-ray spectroscopic methods to the in­ vestigation of chemical b...

  19. Globular cluster X-ray sources

    Science.gov (United States)

    Pooley, D.

    We know from observations that globular clusters are very efficient catalysts in forming unusual binary systems, such as low-mass X-ray binaries (LMXBs), cataclysmic variables (CVs), and millisecond pulsars (MSPs), with formation rates per unit mass exceeding those in the Galactic disk by orders of magnitude. The high stellar densities in globular clusters trigger various dynamical interactions: exchange encounters, direct collisions, destruction of binaries, and tidal capture. This binary population is, in turn, critical to the stabilization of globular clusters against gravitational collapse; the long-term stability of a cluster is thought to depend on tapping into the gravitational binding energy of such close binaries. I will present an overview of the current state of globular cluster X-ray observations, as well as our work on deep Chandra observations of M4, where we reach some of the lowest X-ray luminosities in any globular cluster (comparable to the deep observations of 47 Tuc and NGC 6397). One of M4 X-ray sources previously classified as a white dwarf binary is likely a neutron star binary, and another X-ray source is a sub-subgiant, the nature of which is still unclear. skip=3pt

  20. X-ray irradiation of yeast cells

    Science.gov (United States)

    Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

    1997-10-01

    Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

  1. Review of X-ray Tomography and X-ray Fluorescence Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Shear, Trevor A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-16

    This literature review will focus on both laboratory and synchrotron based X-ray tomography of materials and highlight the inner workings of these instruments. X-ray fluorescence spectroscopy will also be reviewed and applications of the tandem use of these techniques will be explored. The real world application of these techniques during the internship will also be discussed.

  2. X-ray photoelectron spectroscopy, high-resolution X-ray diffraction ...

    Indian Academy of Sciences (India)

    Powder X-ray diffraction studies were carried out on doped lithium niobate for phase identification. High-resolution X-ray diffraction technique was used to study the crystalline quality through full-width at half-maximum values. The refractive index values are more for doped samples than for pure sample as determined by ...

  3. X-ray optics developments at ESA

    DEFF Research Database (Denmark)

    Bavdaz, M.; Wille, E.; Wallace, K.

    2013-01-01

    Future high energy astrophysics missions will require high performance novel X-ray optics to explore the Universe beyond the limits of the currently operating Chandra and Newton observatories. Innovative optics technologies are therefore being developed and matured by the European Space Agency (ESA......) in collaboration with research institutions and industry, enabling leading-edge future science missions. Silicon Pore Optics (SPO) [1 to 21] and Slumped Glass Optics (SGO) [22 to 29] are lightweight high performance X-ray optics technologies being developed in Europe, driven by applications in observatory class...... reflective coatings [30 to 35]. In addition, the progress with the X-ray test facilities and associated beam-lines is discussed [36]. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only....

  4. The quantum X-ray radiology apparatus

    CERN Document Server

    Hilt, B; Prevot, G

    2000-01-01

    The paper entitled 'New Quantum Detection System for Very Low Dose X-ray Radiology', presented at the talk session, discusses the preliminary data obtained using a new quantum X-ray radiology system with a high-efficiency solid-state detector and highly sensitive electronics, making it possible to reduce significantly the dose administered to a patient in X-ray radiology examinations. The present paper focuses more on the technological aspects of the apparatus, such as the integration of the detector with the two Asics, and the computer system. Namely, it is shown how the computer system calibrates the detection system, acquires the data in real time, and controls the scan parameters and image filtering process.

  5. X-ray optics of tapered capillaries.

    Science.gov (United States)

    Balaic, D X; Nugent, K A

    1995-11-01

    The optics of x-ray concentration by tapered glass capillaries is analyzed in terms of a phase-space construction describing their transmission efficiency. The parameters defining the intensity gain are given in terms of parameters describing the x-ray source used, the capillary taper profile, and glass characteristics. We introduce some key concepts in understanding these devices: the extreme ray and a phase-space description of sources and optics. They are used to develop an analytical formulation for the optimum gain characteristics of generalized tapers for use with synchrotrons and other low-divergence sources. This general solution is solved further for the case of conical taper profile. The predictions of this theory are compared with the results of three-dimensional, ray-tracing simulations of x-ray concentration efficiency for conical and paraboloidal tapers.

  6. Bone diagnosis by X-ray techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lima, I. [Nuclear Engineering Program/COPPE/UFRJ, P.O. Box 68509, Av. Horacio Macedo, 2030, Sala I-133, Cidade Universitaria, Zip Code: 21941-972 Rio de Janeiro, RJ (Brazil)], E-mail: inaya@lin.ufrj.br; Anjos, M.J. [Nuclear Engineering Program/COPPE/UFRJ, P.O. Box 68509, Av. Horacio Macedo, 2030, Sala I-133, Cidade Universitaria, Zip Code: 21941-972 Rio de Janeiro, RJ (Brazil); Physics Institute, UERJ (Brazil); Farias, M.L.F. [University Hospital, UFRJ (Brazil); Parcegoni, N.; Rosenthal, D. [Biophysics Institute, UFRJ (Brazil); Duarte, M.E.L. [Histologic and Embriology Department, UFRJ (Brazil); Lopes, R.T. [Nuclear Engineering Program/COPPE/UFRJ, P.O. Box 68509, Av. Horacio Macedo, 2030, Sala I-133, Cidade Universitaria, Zip Code: 21941-972 Rio de Janeiro, RJ (Brazil)

    2008-12-15

    In this work, two X-ray techniques used were 3D microcomputed tomography (micro-CT) and X-ray microfluorescence (micro-XRF) in order to investigate the internal structure of the bone samples. Those two techniques work together, e.g. as a complement to each other, to characterize bones structure and composition. Initially, the specimens were used to do the scan procedure in the microcomputer tomography system and the second step consists of doing the X-ray microfluorescence analysis. The results show that both techniques are powerful methods for analyzing, inspecting and characterizing bone samples: they are alternative procedures for examining bone structures and compositions and they are complementary.

  7. X-ray reflectivity imager with 15 W power X-ray source.

    Science.gov (United States)

    Jiang, Jinxing; Sakurai, Kenji

    2016-09-01

    X-ray reflectivity is usually used for the routine analysis of layered structures of uniform thin films. So far, the technique has some limitations in the application to more practical inhomogeneous/patterned samples. X-ray reflectivity imaging is recently developed technique and can give the reconstructed image from many X-ray reflection projections. The present article gives the instrumental details of the compact X-ray reflectivity imager. Though the power of X-ray source is only 15 W, it works well. The calibration of the system has been discussed, because it is particularly important for the present grazing incidence geometry. We also give a visualization example of the buried interface, physical meaning of the reconstructed image, and discussions about possibilities for improvement.

  8. Differential phase contrast X-ray imaging system and components

    Energy Technology Data Exchange (ETDEWEB)

    Stutman, Daniel; Finkenthal, Michael

    2017-11-21

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  9. Differential phase contrast X-ray imaging system and components

    Science.gov (United States)

    Stutman, Daniel; Finkenthal, Michael

    2017-01-31

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  10. Soft X-ray focusing Telescope aboard AstroSat

    DEFF Research Database (Denmark)

    Singh, K. P.; Dewangan, G. C.; Chandra, S.

    2017-01-01

    The Soft X-ray focusing Telescope (SXT) is a moderateresolution X-ray imaging spectrometer supplementing the ultraviolet and hard X-ray payloads for broadband studies of cosmic sources with AstroSat. Well suited for observing bright X-ray sources, SXT observations of nearby active galactic nuclei...

  11. Grazing Incidence X-ray Scattering and Diffraction

    Indian Academy of Sciences (India)

    ... Journals; Resonance – Journal of Science Education; Volume 19; Issue 12. Grazing Incidence X-ray Scattering and Diffraction. Jaydeep K Basu. General Article Volume 19 Issue 12 December ... Keywords. X-ray reflectivity; X-ray diffuse scattering; grazing incident diffraction; grazing incident; small angle X-ray scattering.

  12. XRASE: The X-Ray Spectroscopic Explorer

    DEFF Research Database (Denmark)

    Schnopper, H.W.; Silver, E.; Murray, S.

    2001-01-01

    The X-Ray Spectroscopic Explorer (XRASE) has a unique combination of features that will make it possible to address many of NASA's scientific goals. These include how galaxy clusters form, the physics and chemistry of the ISM, the heating of stellar coronae, the amount and content of intergalactic...... eV at 6 keV) and efficiency with a field-of-view of 26 arcmin(2) . A deep orbit allows for long, continuous observations. Monitoring instruments in the optical (WOM-X), UV (TAUVEX) and hard X-RAY (GRAM) bands will offer exceptional opportunities to make simultaneous multi-wavelength observations....

  13. Tantalum/Copper X-Ray Targets

    Science.gov (United States)

    Waters, William J.; Edmonds, Brian

    1993-01-01

    Lewis Research Center developed unique solution to subsidiary problem of fabrication of x-ray target. Plasma spraying enabled fabrication of lightweight, high-performance targets. Power settings, atmosphere-control settings, rate of deposition, and other spraying parameters developed. Thin coats of tantalum successfully deposited on copper targets. Targets performed successfully in tests and satisfied all criteria expressed in terms of critical parameters. Significantly reduces projected costs of fabrication of targets and contributes to development of improved, long-lived, lightweight x-ray system.

  14. Studying Microquasars with X-Ray Polarimetry

    Directory of Open Access Journals (Sweden)

    Giorgio Matt

    2018-03-01

    Full Text Available Microquasars are Galactic black hole systems in which matter is transferred from a donor star and accretes onto a black hole of, typically, 10–20 solar masses. The presence of an accretion disk and a relativistic jet made them a scaled down analogue of quasars—thence their name. Microquasars feature prominently in the scientific goals of X-ray polarimeters, because a number of open questions, which are discussed in this paper, can potentially be answered: the geometry of the hot corona believed to be responsible for the hard X-ray emission; the role of the jet; the spin of the black hole.

  15. Hard X-ray Laue monochromator

    Science.gov (United States)

    Kocharyan, V. R.; Gogolev, A. S.; Kiziridi, A. A.; Batranin, A. V.; Muradyan, T. R.

    2016-06-01

    Experimental studies of X-ray diffraction from reflecting atomic planes (10¯11) of X-cut quartz single crystal in Laue geometry influenced by the temperature gradient were carried out. It is shown that by using the temperature gradient it is possible to reflect a hard X- ray beam with photon energy near the 100 keV with high efficiency. It has been experimentally proved that the intensity of the reflected beam can be increased by more than order depending on the value of the temperature gradient.

  16. Radiobiological studies using gamma and x rays.

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Charles Augustus; Longley, Susan W.; Scott, Bobby R.; Lin, Yong; Wilder, Julie; Hutt, Julie A.; Padilla, Mabel T.; Gott, Katherine M.

    2013-02-01

    There are approximately 500 self-shielded research irradiators used in various facilities throughout the U.S. These facilities use radioactive sources containing either 137Cs or 60Co for a variety of biological investigations. A report from the National Academy of Sciences[1] described the issues with security of particular radiation sources and the desire for their replacement. The participants in this effort prepared two peer-reviewed publications to document the results of radiobiological studies performed using photons from 320-kV x rays and 137Cs on cell cultures and mice. The effectiveness of X rays was shown to vary with cell type.

  17. Single Particle X-ray Diffractive Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bogan, M J; Benner, W H; Boutet, S; Rohner, U; Frank, M; Seibert, M; Maia, F; Barty, A; Bajt, S; Riot, V; Woods, B; Marchesini, S; Hau-Riege, S P; Svenda, M; Marklund, E; Spiller, E; Hajdu, J; Chapman, H N

    2007-10-01

    In nanotechnology, strategies for the creation and manipulation of nanoparticles in the gas phase are critically important for surface modification and substrate-free characterization. Recent coherent diffractive imaging with intense femtosecond X-ray pulses has verified the capability of single-shot imaging of nanoscale objects at sub-optical resolutions beyond the radiation-induced damage threshold. By intercepting electrospray-generated particles with a single 15 femtosecond soft-X-ray pulse, we demonstrate diffractive imaging of a nanoscale specimen in free flight for the first time, an important step toward imaging uncrystallized biomolecules.

  18. Applications and measurements of polycapillary x-ray optics.

    Science.gov (United States)

    Macdonald, C A

    1996-01-01

    The recent invention of Kumakhov polycapillary x-ray and neutron optics has expanded the ways x-ray beams can be controlled. X rays incident on the interior of glass tubes at small angles can be guided down the tubes by total external reflection. Now, arrays of curved tapered capillaries can be used to focus, collimate, and filter x-ray radiation. Extensive research is being conducted on the performance and potential applications of these optics. Potential medical applications include mammography, digital energy subtraction angiography, and focused beam therapy. Other applications are x-ray lithography, x-ray astronomy, crystal diffraction, x-ray fluorescence, and neutron prompt gamma analysis.

  19. Image quality assessment and medical physics evaluation of different portable dental X-ray units.

    Science.gov (United States)

    Pittayapat, Pisha; Oliveira-Santos, Christiano; Thevissen, Patrick; Michielsen, Koen; Bergans, Niki; Willems, Guy; Debruyckere, Deborah; Jacobs, Reinhilde

    2010-09-10

    Recently developed portable dental X-ray units increase the mobility of the forensic odontologists and allow more efficient X-ray work in a disaster field, especially when used in combination with digital sensors. This type of machines might also have potential for application in remote areas, military and humanitarian missions, dental care of patients with mobility limitation, as well as imaging in operating rooms. To evaluate radiographic image quality acquired by three portable X-ray devices in combination with four image receptors and to evaluate their medical physics parameters. Images of five samples consisting of four teeth and one formalin-fixed mandible were acquired by one conventional wall-mounted X-ray unit, MinRay 60/70 kVp, used as a clinical standard, and three portable dental X-ray devices: AnyRay 60 kVp, Nomad 60 kVp and Rextar 70 kVp, in combination with a phosphor image plate (PSP), a CCD, or a CMOS sensor. Three observers evaluated images for standard image quality besides forensic diagnostic quality on a 4-point rating scale. Furthermore, all machines underwent tests for occupational as well as patient dosimetry. Statistical analysis showed good quality imaging for all system, with the combination of Nomad and PSP yielding the best score. A significant difference in image quality between the combination of the four X-ray devices and four sensors was established (p1m: Rextar <0.2 microGy, MinRay <0.1 microGy). The present study demonstrated the feasibility of three portable X-ray systems to be used for specific indications, based on acceptable image quality and sufficient accuracy of the machines and following the standard guidelines for radiation hygiene. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  20. X-ray shout echoing through space

    Science.gov (United States)

    2004-01-01

    a flash of X-rays hi-res Size hi-res: 3991 Kb Credits: ESA, S. Vaughan (University of Leicester) EPIC camera shows the expanding rings caused by a flash of X-rays XMM-Newton's X-ray EPIC camera shows the expanding rings caused by a flash of X-rays scattered by dust in our Galaxy. The X-rays were produced by a powerful gamma-ray burst that took place on 3 December 2003. The slowly fading afterglow of the gamma-ray burst is at the centre of the expanding rings. Other, unrelated, X-ray sources can also be seen. The time since the gamma-ray explosion is shown in each panel in hours. At their largest size, the rings would appear in the sky about five times smaller than the full moon. a flash of X-rays hi-res Size hi-res: 2153 Kb Credits: ESA, S. Vaughan (University of Leicester) EPIC camera shows the expanding rings caused by a flash of X-rays (Please choose "hi-res" version for animation) XMM-Newton's X-ray EPIC camera shows the expanding rings caused by a flash of X-rays scattered by dust in our Galaxy. The X-rays were produced by a powerful gamma-ray burst that took place on 3 December 2003. The slowly fading afterglow of the gamma-ray burst is at the centre of the expanding rings. Other, unrelated, X-ray sources can also be seen. The time since the gamma-ray explosion is shown in each panel in seconds. At their largest size, the rings would appear in the sky about five times smaller than the full moon. This echo forms when the powerful radiation of a gamma-ray burst, coming from far away, crosses a slab of dust in our Galaxy and is scattered by it, like the beam of a lighthouse in clouds. Using the expanding rings to precisely pin-point the location of this dust, astronomers can identify places where new stars and planets are likely to form. On 3 December 2003 ESA's observatory, Integral, detected a burst of gamma rays, lasting about 30 seconds, from the direction of a distant galaxy. Within minutes of the detection, thanks to a sophisticated alert network, many

  1. X-ray insights into star and planet formation

    OpenAIRE

    Feigelson, Eric D.

    2010-01-01

    Although stars and planets form in cold environments, X-rays are produced in abundance by young stars. This review examines the implications of stellar X-rays for star and planet formation studies, highlighting the contributions of NASA’s (National Aeronautics and Space Administration) Chandra X-ray Observatory. Seven topics are covered: X-rays from protostellar outflow shocks, X-rays from the youngest protostars, the stellar initial mass function, the structure of young stellar clusters, the...

  2. X-ray Chirped Pulse Amplification: towards GW Soft X-ray Lasers

    Directory of Open Access Journals (Sweden)

    Marta Fajardo

    2013-07-01

    Full Text Available Extensive modeling of the seeding of plasma-based soft X-ray lasers is reported in this article. Seminal experiments on amplification in plasmas created from solids have been studied in detail and explained. Using a transient collisional excitation scheme, we show that a 18 µJ, 80 fs fully coherent pulse is achievable by using plasmas pumped by a compact 10 Hz laser. We demonstrate that direct seeding of plasmas created by nanosecond lasers is not efficient. Therefore, we propose and fully study the transposition to soft X-rays of the Chirped Pulse Amplification (CPA technique. Soft X-ray pulses with energy of 6 mJ and 200 fs duration are reachable by seeding plasmas pumped by compact 100 J, sub-ns, 1 shot/min lasers. These soft X-ray lasers would reach GW power, corresponding to an increase of 100 times as compared to the highest peak power achievable nowadays in the soft X-ray region (30 eV–1 keV. X-ray CPA is opening new horizon for soft x-ray ultra-intense sources.

  3. Global Properties of X-Ray Flashes and X-Ray-Rich GRBs Observed by Swift

    Science.gov (United States)

    Sakamoto, T.; Yamazaki, R.; Cummings, J.; Krimm, H.; Parsons, A.; Hullinger, D.; Barbier, L.; Fenimore, E.; Markwardt, C.; Tueller, J.; hide

    2007-01-01

    We describe and discuss the spectral and temporal characteristics of the prompt emission and X-ray afterglow emission of X-ray flashes (XRFs) detected and observed by Swift between December 2005 and September 2006. We compare these characteristics to a sample of X-ray rich gamma-ray bursts (XRRs) and conventional classical gamma-ray bursts (C-GRBs)observed during the same period. We confirm the correlation between Epeak and fluence noted by others and find further evidence that XRFs and C-GRBs form a continuum. We also confirmed that our known redshift samples are consistent with the correlation between the peak energy (Epeak) and the isotropic radiated energy (Eiso), so called the Epeak-Eiso relation. The spectral properties of X-ray afterglows are similar to those of gamma-ray burst afterglows, but the temporal properties of the two classes are quite different. We found that the light curves of C-GRBs afterglow show a break to steeper indices (shallow-to-steep break) at much earlier times than do XRF afterglows. Moreover, the overall luminosity of X-ray afterglows of XRFs are systematically smaller by a factor of two or more compared with that of C-GRBs. These distinct differences in the X-ray afterglow between XRFs and C-GRBs are key to understanding not only a mysterious shallow-to-steep phase in the X-ray afterglow but also the unique nature of XRFs.

  4. Compact stellar X-ray sources

    NARCIS (Netherlands)

    Lewin, W.H.G.; van der Klis, M.

    2006-01-01

    X-ray astronomy is the prime available window on astrophysical compact objects: black holes, neutron stars and white dwarfs. In the last ten years new observational opportunities have led to an explosion of knowledge in this field. This book provides a comprehensive overview of the astrophysics of

  5. ROSAT: X ray survey of compact groups

    NARCIS (Netherlands)

    van Gorkom, Jacqueline

    1993-01-01

    This is the final technical report on grant NAG5-1954, which was awarded under the NASA ROSAT Guest Investigator Program to Columbia University. This grant was awarded for a number of projects on two rather different topics: (1) an x-ray survey of compact groups of galaxies; and (2) the fate of gas

  6. Fourier techniques in X-ray timing

    NARCIS (Netherlands)

    van der Klis, M.

    1988-01-01

    Basic principles of Fourier techniques often used in X-ray time series analysis are reviewed. The relation between the discrete Fourier transform and the continuous Fourier transform is discussed to introduce the concepts of windowing and aliasing. The relation is derived between the power spectrum

  7. A microcapillary lens for X-rays

    CERN Document Server

    Dudchik, Y I

    1999-01-01

    A new design of a compound refractive lens for X-rays is proposed. The lens is made as a set of glue microlenses placed in a glass capillary. The technique of lens fabrication is described. Results of ray tracing calculations for 8 and 15 keV photons are represented.

  8. X-ray optics for axion helioscopes

    DEFF Research Database (Denmark)

    Jakobsen, Anders Clemen; Pivovaroff, Michael J.; Christensen, Finn Erland

    2013-01-01

    A method of optimizing grazing incidence x-ray coatings in ground based axion helioscopes is presented. Software has been been developed to find the optimum coating when taking both axion spectrum and Micromegas detector quantum efficiency into account. A comparison of the relative effective area...... of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only....

  9. Exploring subluminous X-ray binaries

    NARCIS (Netherlands)

    Degenaar, N.D.

    2010-01-01

    Halfway the twentieth century, technological developments made it possible to carry detection instruments outside the absorbing layers of the Earth’s atmosphere onboard rockets and satellites. This opened up the opportunity to detect the emission from celestial objects at X-ray wavelengths, thereby

  10. Techniques in X-ray Astronomy

    Indian Academy of Sciences (India)

    Kulinder Pal Singh is in the Department of. Astronomy and Astro- physics of the Tata. Institute of Fundamental. Research, Mumbai. His primary fields of research are X-ray studies of hot plasmas in stars, super- nova remnants, galaxies, intergalactic medium in clusters of galaxies, active galactic nuclei, cataclys- mic variables ...

  11. Supernova remnants: the X-ray perspective

    NARCIS (Netherlands)

    Vink, J.

    2012-01-01

    Supernova remnants are beautiful astronomical objects that are also of high scientific interest, because they provide insights into supernova explosion mechanisms, and because they are the likely sources of Galactic cosmic rays. X-ray observations are an important means to study these objects. And

  12. Reconstructing misaligned x-ray CT data

    Energy Technology Data Exchange (ETDEWEB)

    Divin, C. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-24

    Misalignment errors for x-ray computed tomography (CT) systems can manifest as artifacts and a loss of spatial and contrast resolution. To mitigate artifacts, significant effort is taken to determine the system geometry and minimizing any residual error in the system alignment. This project improved our ability to post-correct data which was acquired on a misaligned CT system.

  13. X-ray signals in renal osteopathy

    Energy Technology Data Exchange (ETDEWEB)

    Rieden, K.

    1984-10-01

    Chronic renal insufficiency is associated with metabolic disturbances which ultimately lead to typical, partly extremely painful changes in the skeletal system the longer the disease persists. Regular X-ray control of certain skeletal segments allows early detection of renal oesteopathy if the radiological findings described in this article are carefully scrutinised and interpreted.

  14. X-ray Studies of Flaring Plasma

    Indian Academy of Sciences (India)

    We present some methods of X-ray data analysis employed in our laboratory for deducing the physical parameters of flaring plasma. For example, we have used a flare well observed with Polish instrument RESIK aboard Russian CORONAS-F satellite. Based on a careful instrument calibration, the absolute fluxes in a ...

  15. X-ray microscopy of human malaria

    Energy Technology Data Exchange (ETDEWEB)

    Magowan, C.; Brown, J.T.; Mohandas, N.; Meyer-Ilse, W. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Associations between intracellular organisms and host cells are complex and particularly difficult to examine. X-ray microscopy provides transmission images of subcellular structures in intact cells at resolutions superior to available methodologies. The spatial resolution is 50-60nm with a 1 micron depth of focus, superior to anything achievable with light microscopy. Image contrast is generated by differences in photoelectric absorption by the atoms in different areas (i.e. subcellular structures) throughout the full thickness of the sample. Absorption due to carbon dominates among all the elements in the sample at 2.4 nm x-ray wavelength. Thus images show features or structures, in a way not usually seen by other types of microscopy. The authors used soft x-ray microscopy to investigate structural development of Plasmodium falciparum malaria parasites in normal and genetically abnormal erythrocytes, and in infected erythrocytes treated with compounds that have anti-malarial effects. X-ray microscopy showed newly elaborated structures in the cytosol of unstained, intact erythrocytes, redistribution of mass (carbon) in infected erythrocytes, and aberrant parasite morphology. Better understanding of the process of intracellular parasite maturation and the interactions between the parasite and its host erythrocyte can help define new approaches to the control of this deadly disease.

  16. X-Ray Exam: Cervical Spine

    Science.gov (United States)

    ... open mouth (odontoid view). Occasionally, additional pictures like flexion and extension views of the cervical spine might be needed. continue Why It's Done A cervical spine X-ray can help find the cause of symptoms such as neck, shoulder, upper back, or arm pain, as well ...

  17. X-Ray Exam: Femur (Upper Leg)

    Science.gov (United States)

    ... leg, and an image is recorded on special film or a computer. This image shows the soft tissues and the bone in the upper leg, which is called the femur. The X-ray image is black and white. Dense body parts that block the passage of the X- ...

  18. PREPARATION, SPECTROSCOPIC STUDIES AND X-RAY ...

    African Journals Online (AJOL)

    These complexes have been characterized by analysis, molar conductance, magnetic measurements, infrared spectral studies and X-ray diffraction. The analytical data showed 1:3 (metal:ligand) stoichiometry. Molar conductance measurements in dmf indicate 1:3 electrolytes in all cases. Magnetic moment values are close ...

  19. Kinematic X-Ray Analysis Apparatus

    NARCIS (Netherlands)

    Koningsberger, D.C.; Brinkgreve, P.

    1983-01-01

    In an X-ray analysis apparatus, a moving mechanism is provided by a main guide member along which a main slide device can be displaced. Rotatably connected with the main slide device is a detector guide member along which a detection slide device is displaced. The main slide device, as well as the

  20. X-ray spectroscopy of manganese clusters

    Energy Technology Data Exchange (ETDEWEB)

    Grush, M.M. [Univ. of California, Davis, CA (United States). Dept. of Applied Science]|[Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

    1996-06-01

    Much of this thesis represents the groundwork necessary in order to probe Mn clusters more productively than with conventional Mn K-edge XAS and is presented in Part 1. Part 2 contains the application of x-ray techniques to Mn metalloproteins and includes a prognosis at the end of each chapter. Individual Mn oxidation states are more readily distinguishable in Mn L-edge spectra. An empirical mixed valence simulation routine for determining the average Mn oxidation state has been developed. The first Mn L-edge spectra of a metalloprotein were measured and interpreted. The energy of Mn K{beta} emission is strongly correlated with average Mn oxidation state. K{beta} results support oxidation states of Mn(III){sub 2}(IV){sub 2} for the S{sub 1} state of Photosystem II chemical chemically reduced preparations contain predominantly Mn(II). A strength and limitation of XAS is that it probes all of the species of a particular element in a sample. It would often be advantageous to selectively probe different forms of the same element. The first demonstration that chemical shifts in x-ray fluorescence energies can be used to obtain oxidation state-selective x-ray absorption spectra is presented. Spin-dependent spectra can also be used to obtain a more simplified picture of local structure. The first spin-polarized extended x-ray absorption fine structure using Mn K{beta} fluorescence detection is shown.

  1. Harmonic lasing in X-ray FELs

    Energy Technology Data Exchange (ETDEWEB)

    Schneidmiller, E.A.; Yurkov, M.V.

    2012-05-15

    Harmonic lasing in a free electron laser with a planar undulator (under the condition that the fundamental frequency is suppressed) might be a cheap and efficient way of extension of wavelength ranges of existing and planned X-ray FEL facilities. Contrary to nonlinear harmonic generation, harmonic lasing can provide much more intense, stable, and narrow-band FEL beam which is easier to handle due to the suppressed fundamental frequency. In this paper we perform a parametrization of the solution of the eigenvalue equation for lasing at odd harmonics, and present an explicit expression for FEL gain length, taking into account all essential effects. We propose and discuss methods for suppression of the fundamental harmonic. We also suggest a combined use of harmonic lasing and lasing at the retuned fundamental wavelength in order to reduce bandwidth and to increase brilliance of X-ray beam at saturation. Considering 3rd harmonic lasing as a practical example, we come to the conclusion that it is much more robust than usually thought, and can be widely used in the existing or planned X-ray FEL facilities. In particular, LCLS after a minor modification can lase to saturation at the 3rd harmonic up to the photon energy of 25-30 keV providing multi-gigawatt power level and narrow bandwidth. As for the European XFEL, harmonic lasing would allow to extend operating range (ultimately up to 100 keV), to reduce FEL bandwidth and to increase brilliance, to enable two-color operation for pump-probe experiments, and to provide more flexible operation at different electron energies. Similar improvements can be realized in other X-ray FEL facilities with gap-tunable undulators like FLASH II, SACLA, LCLS II, etc. Harmonic lasing can be an attractive option for compact X-ray FELs (driven by electron beams with a relatively low energy), allowing the use of the standard undulator technology instead of small-gap in-vacuum devices. Finally, in this paper we discover that in a part of the

  2. Mystery of Cometary X-Rays Solved

    Science.gov (United States)

    2000-07-01

    On July 14, 2000 NASA's Chandra X-ray Observatory imaged Comet C/1999 S4 (LINEAR) and detected X-rays from oxygen and nitrogen ions. The details of the X-ray emission, as recorded on Chandra's Advanced CCD Imaging Spectrometer, show that they are produced by collisions of ions racing away from the Sun with gas in the comet. "This observation solves one mystery. It proves how comets produce X-rays," said Dr. Carey Lisse of the Space Telescope Science Institute (STScI) leader of a team of scientists from STScI, NASA's Goddard Space Flight Center, Max Planck Institute in Germany, Johns Hopkins University, the University of California, Berkeley, and the Harvard-Smithsonian Center for Astrophysics. "With an instrument like Chandra, we can now study the chemistry of the solar wind, and observe the X-ray glow from the atmospheres of comets as well as planets such as Venus. It may even be possible to observe other, nearby solar systems." Comets, which resemble "dirty snow balls" a few miles in diameter, were thought to be too cold for such energetic emission, so the detection of X-rays by the ROSAT observatory from comet Hyakutake in 1996 was a surprise. Several explanations were suggested, but the source of cometary X-ray emission remained a puzzle until the Chandra observation of Comet C/1999 S4 (LINEAR). Chandra's imaging spectrometer revealed a strong X-ray signal from oxygen and nitrogen ions, clinching the case for the production of X-rays due to the exchange of electrons in collisions between nitrogen and oxygen ions in the solar wind and electrically neutral elements (predominantly hydrogen) in the comets atmosphere. The Chandra observation was taken with the Advanced CCD Imaging Spectrometer (ACIS) on July 14, 2000 for a total of 2 ½ hours. The comet will be re-observed with Chandra during the weeks of July 29 - Aug 13. Comet C/1999 S4 (LINEAR) was discovered in September 1999 by the Lincoln Near Earth Asteroid Research (LINEAR) project, which is operated by the

  3. Machine learning for cardiac ultrasound time series data

    Science.gov (United States)

    Yuan, Baichuan; Chitturi, Sathya R.; Iyer, Geoffrey; Li, Nuoyu; Xu, Xiaochuan; Zhan, Ruohan; Llerena, Rafael; Yen, Jesse T.; Bertozzi, Andrea L.

    2017-03-01

    We consider the problem of identifying frames in a cardiac ultrasound video associated with left ventricular chamber end-systolic (ES, contraction) and end-diastolic (ED, expansion) phases of the cardiac cycle. Our procedure involves a simple application of non-negative matrix factorization (NMF) to a series of frames of a video from a single patient. Rank-2 NMF is performed to compute two end-members. The end members are shown to be close representations of the actual heart morphology at the end of each phase of the heart function. Moreover, the entire time series can be represented as a linear combination of these two end-member states thus providing a very low dimensional representation of the time dynamics of the heart. Unlike previous work, our methods do not require any electrocardiogram (ECG) information in order to select the end-diastolic frame. Results are presented for a data set of 99 patients including both healthy and diseased examples.

  4. Development of a Wolter Optic X-ray Imager on Z

    Science.gov (United States)

    Fein, Jeffrey R.; Ampleford, David J.; Vogel, Julia K.; Kozioziemski, Bernie; Walton, Christopher C.; Wu, Ming; Ayers, Jay; Ball, Chris J.; Bourdon, Chris J.; Maurer, Andrew; Pivovaroff, Mike; Ramsey, Brian; Romaine, Suzanne

    2017-10-01

    A Wolter optic x-ray imager is being developed for the Z Machine to study the dynamics of warm x-ray sources with energies above 10 keV. The optic is adapted from observational astronomy and uses multilayer-coated, hyperbolic and parabolic x-ray mirrors to form a 2D image with predicted 100- μm resolution over a 5x5-mm field of view. The imager is expected to have several advantages over a simple pinhole camera. In particular, it can form quasi mono-energetic images due to the inherent band-pass nature of the x-ray mirrors from Bragg diffraction. As well, its larger collection solid angle can lead to an overall increase in efficiency for the x-rays in the desirable energy band. We present the design of the imaging system, which is initially optimized to view Mo K-alpha x-rays (17.5 keV). In addition, we will present preliminary measurements of the point-spread function as well as the spectral sensitivity of the instrument. Sandia National Laboratories is a multimission laboratory managed and operated by NTESS, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE's NNSA under contract DE-NA-0003525.

  5. Principles of femtosecond X-ray/optical cross-correlation with X-ray induced transient optical reflectivity in solids

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, S., E-mail: sebastian.eckert@helmholtz-berlin.de, E-mail: martin.beye@helmholtz-berlin.de; Beye, M., E-mail: sebastian.eckert@helmholtz-berlin.de, E-mail: martin.beye@helmholtz-berlin.de; Pietzsch, A.; Quevedo, W.; Hantschmann, M. [Institute for Methods and Instrumentation in Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Ochmann, M.; Huse, N. [Institute for Nanostructure and Solid State Physics, University of Hamburg, Jungiusstr. 11, 20355 Hamburg, Germany and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg (Germany); Ross, M.; Khalil, M. [Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195 (United States); Minitti, M. P.; Turner, J. J.; Moeller, S. P.; Schlotter, W. F.; Dakovski, G. L. [LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Föhlisch, A. [Institute for Methods and Instrumentation in Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Potsdam (Germany)

    2015-02-09

    The discovery of ultrafast X-ray induced optical reflectivity changes enabled the development of X-ray/optical cross correlation techniques at X-ray free electron lasers worldwide. We have now linked through experiment and theory the fundamental excitation and relaxation steps with the transient optical properties in finite solid samples. Therefore, we gain a thorough interpretation and an optimized detection scheme of X-ray induced changes to the refractive index and the X-ray/optical cross correlation response.

  6. Neutron and X-ray Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Carini, Gabriella [SLAC National Accelerator Lab., Menlo Park, CA (United States); Denes, Peter [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gruener, Sol [Cornell Univ., Ithaca, NY (United States); Lessner, Elianne [Dept. of Energy (DOE), Washington DC (United States). Office of Science Office of Basic Energy Sciences

    2012-08-01

    The Basic Energy Sciences (BES) X-ray and neutron user facilities attract more than 12,000 researchers each year to perform cutting-edge science at these state-of-the-art sources. While impressive breakthroughs in X-ray and neutron sources give us the powerful illumination needed to peer into the nano- to mesoscale world, a stumbling block continues to be the distinct lag in detector development, which is slowing progress toward data collection and analysis. Urgently needed detector improvements would reveal chemical composition and bonding in 3-D and in real time, allow researchers to watch “movies” of essential life processes as they happen, and make much more efficient use of every X-ray and neutron produced by the source The immense scientific potential that will come from better detectors has triggered worldwide activity in this area. Europe in particular has made impressive strides, outpacing the United States on several fronts. Maintaining a vital U.S. leadership in this key research endeavor will require targeted investments in detector R&D and infrastructure. To clarify the gap between detector development and source advances, and to identify opportunities to maximize the scientific impact of BES user facilities, a workshop on Neutron and X-ray Detectors was held August 1-3, 2012, in Gaithersburg, Maryland. Participants from universities, national laboratories, and commercial organizations from the United States and around the globe participated in plenary sessions, breakout groups, and joint open-discussion summary sessions. Sources have become immensely more powerful and are now brighter (more particles focused onto the sample per second) and more precise (higher spatial, spectral, and temporal resolution). To fully utilize these source advances, detectors must become faster, more efficient, and more discriminating. In supporting the mission of today’s cutting-edge neutron and X-ray sources, the workshop identified six detector research challenges

  7. Forensics, radiology, society. X-rays. Tool and document

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Beatrice; Vogel, Hermann [Hamburg Univ. (Germany). Inst. of Forensic Medicine

    2014-07-01

    During the last years, the individual specialities of forensic medicine and diagnostic imaging have increasingly cooperated to create the interdisciplinary entity of forensic radiology. The book demonstrates the potential of this speciality: It has become evident that the combination of diagnostic imaging and forensic medicine solves more cases of death of unknown cause than each alone, and that a radiograph can be read like a document describing forces of modern time and its effects on current society. The posters of 6 exhibitions demonstrate the actual cause of death and its preceding violence. They aim at the medical as well as the interested lay-public: Causes of natural and of violent death become visible. For instance, stab- and gunshot wounds into a person's rear are contradictory of self-defence. Stab wounds with penetration of ribs indicate great force and, therefore, intentional homicide. The same is valid for multiple stabs, stabs through silicon prosthesis of a mammoplasty, and stabs into the breast cage of a defenceless toddler. X-rays of the living can indicate preceding torture. X-rays are part of the security technology employed at airports and countries' borders. They help to detect drugs, explosives, and human stow-aways. The x-ray examination of the deceased visualises success and failure of the preceding therapy. After reanimation, the position of a tracheal tube, the effects of a vascular puncture, and potential fractures of the breast cage can be evaluated. After cardiac and aortic interventions, the procedure of choice and its effects can be seen. Concerning general or intensive care, diagnostic imaging shows the position of urinary catheters, gastric tubes and vascular catheters. Prenatal diagnostic imaging can determine the sex of the foetus and possible malformations; and in peri- and postnatal death, it may show the effects of iatrogenic actions, and later on, of child-abuse.

  8. Influence by x-ray facula on dimension measurement

    Science.gov (United States)

    Qin, Xulei; Li, Ye; Duanmu, Qingduo; Zhao, Peng

    2015-03-01

    Based on the imaging features of the original image intensifier of X-ray, the light halo caused by X-ray projective halation is analyzed, the result shows the stray X-ray energy is lower than the direct X-ray energy. The screen brightness generated by the image intensifier of X-ray stimulated by the stray X-ray energy is weaker than that generated by the direct X-ray energy. In addition the projector facula reflected from the direct X-ray is focused on the central region of X-ray image intensifier, therefore a toroidal ring similar to the solar halation is formed around the projector halation. The results of the theoretical analysis and experimental discovery show this phenomenon caused by X-ray tube on X-ray image intensifier can not be eliminated and in the system of X-ray size detection composed of them the X-ray halation will reduce the detection accuracy resulting in measurement results' deviation dispersion under given conditions. This kind of nonlinear system error can not be canceled out by the segmented modification of coefficient compensation but it can be restrained through the adjustment of correction coefficients. After the physical testing and comparison of the physical normal size the accuracy of 0.1mm of the compensated X-ray measurement results after the adjustment of correction coefficient has been reached. The results are highly reproducible and the method of the segmented coefficient compensation has been improved.

  9. X-ray scattering measurements from thin-foil x-ray mirrors

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; BYRNAK, BP; Hornstrup, Allan

    1992-01-01

    Thin foil X-ray mirrors are to be used as the reflecting elements in the telescopes of the X-ray satellites Spectrum-X-Gamma (SRG) and ASTRO-D. High resolution X-ray scattering measurements from the Au coated and dip-lacquered Al foils are presented. These were obtained from SRG mirrors positioned...... in a test quadrant of the telescope structure and from ASTRO-D foils held in a simple fixture. The X-ray data is compared with laser data and other surface structure data such as STM, atomic force microscopy (AFM), TEM, and electron micrography. The data obtained at Cu K-alpha(1), (8.05 keV) from all...

  10. X-ray optics the diffraction of X-rays by finite and imperfect crystals

    CERN Document Server

    Wilson, Arthur J C

    1949-01-01

    This fascinating text contains a detailed treatise on the use of X-Ray optics in the taxonomy of minerals and gem stones. An interesting and informative book on the subject, X-Ray Optics - The Diffraction of X-Rays by Finite and Imperfect Crystals is a must-have for anyone with an interest the study of crystals and constitutes a great addition to any gemmological collection. Arthur James Cochran Wilson (28 November 1914 - 1 July 1995) was a Canadian crystallographer, most famous for his contributions to X-ray crystallography and elected as a Fellow of the Royal Society in 1963. This book has been elected for republication now due to its immense educational value, and is proudly republished here complete with a new introduction to the subject.

  11. X-Ray Optics on a Chip: Guiding X Rays in Curved Channels.

    Science.gov (United States)

    Salditt, T; Hoffmann, S; Vassholz, M; Haber, J; Osterhoff, M; Hilhorst, J

    2015-11-13

    We study the propagation of hard x rays in single curved x-ray waveguide channels and observe waveguide effects down to surprisingly small radii of curvature R≃10  mm and a large contour length s≃5  mm, deflecting beams up to 30°. At these high angles, about 2 orders of magnitude above the critical angle of total reflection θ(c), most radiation modes are lost by "leaking" into the cladding, while certain "survivor" modes persist. This may open up a new form of integrated x-ray optics "on a chip," requiring curvatures mostly well below the extreme values studied here, e.g., to split and to delay x-ray pulses.

  12. Soft X-ray Absorbers Enabling Study of the Diffuse X-ray Background Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Absorbers for soft x-rays need to be made thinner and with larger area, to collect more photons, and with minimal number of support stems. However, the structure is...

  13. Calculation of x-ray scattering patterns from nanocrystals at high x-ray intensity

    Directory of Open Access Journals (Sweden)

    Malik Muhammad Abdullah

    2016-09-01

    Full Text Available We present a generalized method to describe the x-ray scattering intensity of the Bragg spots in a diffraction pattern from nanocrystals exposed to intense x-ray pulses. Our method involves the subdivision of a crystal into smaller units. In order to calculate the dynamics within every unit, we employ a Monte-Carlo-molecular dynamics-ab-initio hybrid framework using real space periodic boundary conditions. By combining all the units, we simulate the diffraction pattern of a crystal larger than the transverse x-ray beam profile, a situation commonly encountered in femtosecond nanocrystallography experiments with focused x-ray free-electron laser radiation. Radiation damage is not spatially uniform and depends on the fluence associated with each specific region inside the crystal. To investigate the effects of uniform and non-uniform fluence distribution, we have used two different spatial beam profiles, Gaussian and flattop.

  14. X-Ray Scattering Applications Using Pulsed X-Ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Larson, B.C.

    1999-05-23

    Pulsed x-ray sources have been used in transient structural phenomena investigations for over fifty years; however, until the advent of synchrotrons sources and the development of table-top picosecond lasers, general access to ligh temporal resolution x-ray diffraction was relatively limited. Advances in diffraction techniques, sample excitation schemes, and detector systems, in addition to IncEased access to pulsed sources, have ld tO what is now a diverse and growing array of pulsed-source measurement applications. A survey of time-resolved investigations using pulsed x-ray sources is presented and research opportunities using both present and planned pulsed x-ray sources are discussed.

  15. Behavior of characteristic X-rays from a partial-transmission-type X-ray target.

    Science.gov (United States)

    Raza, Hamid Saeed; Kim, Hyun Jin; Ha, Jun Mok; Cho, Sung Oh

    2013-10-01

    The angular distribution of characteristic X-rays using a partial-transmission tungsten target was analyzed. Twenty four tallies were modeled to cover a 360° envelope around the target. The Monte Carlo N-Particle (MCNP5) simulation results revealed that the characteristic X-ray flux is not always isotropic around the target. Rather, the flux mainly depends on the target thickness and the energy of the incident electron beam. A multi-energy photon generator is proposed to emit high-energy characteristic X-rays, where the target acts as a filter for the low-energy characteristic X-rays. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Quality control assessment of diagnostic X-ray facilities in Ghana ...

    African Journals Online (AJOL)

    Twenty-three X-ray machines located at 20 different hospitals in Ghana were assessed for quality assurance and control. The radiographic parameters evaluated were tube voltage and current, tube output consistency variation with kilovoltage (kV) and current-time (mAs) factor, exposure time accuracy and beam quality as ...

  17. Study of runaway electrons with Hard X-ray spectrometry of tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Shevelev, A.; Chugunov, I.; Khilkevitch, E.; Gin, D.; Doinikov, D.; Naidenov, V. [Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Polytechnicheskaya 26, St. Petersburg, 194021 (Russian Federation); Kiptily, V. [EURATOM / CCFE Fusion Association, Abingdon, OX14 3DB (United Kingdom); Plyusnin, V. [Instituto de Plasmas e Fusão Nuclear, Associação EURATOM-IST, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Collaboration: EFDA-JET Contributors

    2014-08-21

    Hard-X-ray spectrometry is a tool widely used for diagnostic of runaway electrons in existing tokamaks. In future machines, ITER and DEMO, HXR spectrometry will be useful providing information on runaway electron energy, runaway beam current and its profile during disruption.

  18. Monolithic CMOS imaging x-ray spectrometers

    Science.gov (United States)

    Kenter, Almus; Kraft, Ralph; Gauron, Thomas; Murray, Stephen S.

    2014-07-01

    The Smithsonian Astrophysical Observatory (SAO) in collaboration with SRI/Sarnoff is developing monolithic CMOS detectors optimized for x-ray astronomy. The goal of this multi-year program is to produce CMOS x-ray imaging spectrometers that are Fano noise limited over the 0.1-10keV energy band while incorporating the many benefits of CMOS technology. These benefits include: low power consumption, radiation "hardness", high levels of integration, and very high read rates. Small format test devices from a previous wafer fabrication run (2011-2012) have recently been back-thinned and tested for response below 1keV. These devices perform as expected in regards to dark current, read noise, spectral response and Quantum Efficiency (QE). We demonstrate that running these devices at rates ~> 1Mpix/second eliminates the need for cooling as shot noise from any dark current is greatly mitigated. The test devices were fabricated on 15μm, high resistivity custom (~30kΩ-cm) epitaxial silicon and have a 16 by 192 pixel format. They incorporate 16μm pitch, 6 Transistor Pinned Photo Diode (6TPPD) pixels which have ~40μV/electron sensitivity and a highly parallel analog CDS signal chain. Newer, improved, lower noise detectors have just been fabricated (October 2013). These new detectors are fabricated on 9μm epitaxial silicon and have a 1k by 1k format. They incorporate similar 16μm pitch, 6TPPD pixels but have ~ 50% higher sensitivity and much (3×) lower read noise. These new detectors have undergone preliminary testing for functionality in Front Illuminated (FI) form and are presently being prepared for back thinning and packaging. Monolithic CMOS devices such as these, would be ideal candidate detectors for the focal planes of Solar, planetary and other space-borne x-ray astronomy missions. The high through-put, low noise and excellent low energy response, provide high dynamic range and good time resolution; bright, time varying x-ray features could be temporally and

  19. X-RAY POLARIZATION FROM HIGH-MASS X-RAY BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Kallman, T. [NASA/GSFC, Code 662, Greenbelt, MD 20771 (United States); Dorodnitsyn, A. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Blondin, J. [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States)

    2015-12-10

    X-ray astronomy allows study of objects that may be associated with compact objects, i.e., neutron stars or black holes, and also may contain strong magnetic fields. Such objects are categorically nonspherical, and likely noncircular when projected on the sky. Polarization allows study of such geometric effects, and X-ray polarimetry is likely to become feasible for a significant number of sources in the future. Potential targets for future X-ray polarization observations are the high-mass X-ray binaries (HMXBs), which consist of a compact object in orbit with an early-type star. In this paper we show that X-ray polarization from HMXBs has a distinct signature that depends on the source inclination and orbital phase. The presence of the X-ray source displaced from the star creates linear polarization even if the primary wind is spherically symmetric whenever the system is viewed away from conjunction. Direct X-rays dilute this polarization whenever the X-ray source is not eclipsed; at mid-eclipse the net polarization is expected to be small or zero if the wind is circularly symmetric around the line of centers. Resonance line scattering increases the scattering fraction, often by large factors, over the energy band spanned by resonance lines. Real winds are not expected to be spherically symmetric, or circularly symmetric around the line of centers, owing to the combined effects of the compact object gravity and ionization on the wind hydrodynamics. A sample calculation shows that this creates polarization fractions ranging up to tens of percent at mid-eclipse.

  20. ZBLAN-based x-ray storage phosphors and scintillators for digital x-ray imaging

    Science.gov (United States)

    Chen, Gang; Johnson, Jacqueline A.; Weber, Richard; Schweizer, Stefan; MacFarlane, Douglas; Woodford, John; De Carlo, Francesco

    2005-04-01

    X-ray storage phosphors have several advantages over traditional films as well as digital X-ray detectors based on thin-film transistors (TFT). Commercially used storage phosphors do not have high resolution due to light scattering from powder grains. To solve this problem, we have developed storage phosphor plates based on modified fluorozirconate (ZBLAN) glasses. The newly developed imaging plates are "grainless" and, therefore, can significantly reduce light scattering and improve image resolution. To study the structure and image performance of the novel storage phosphor plates, we conducted X-ray diffraction (XRD) and X-ray imaging analyses at the Advanced Photon Source, Argonne National Laboratory. The XRD results show that BaCl2 crystallites are embedded in the glass matrix. These crystallites enlarge and are under residual stress after heat treatment. The X-ray imaging study shows that these storage phosphor plates have a much better resolution than a commercially used storage phosphor screen. The results also show that some of the glass ceramics are high-resolution scintillators. Our study demonstrates that these fluorozirconate-based glass ceramics are a promising candidate for high-resolution digital X-ray detectors for both medical and scientific research purposes.

  1. HERMES: a soft X-ray beamline dedicated to X-ray microscopy.

    Science.gov (United States)

    Belkhou, Rachid; Stanescu, Stefan; Swaraj, Sufal; Besson, Adrien; Ledoux, Milena; Hajlaoui, Mahdi; Dalle, Didier

    2015-07-01

    The HERMES beamline (High Efficiency and Resolution beamline dedicated to X-ray Microscopy and Electron Spectroscopy), built at Synchrotron SOLEIL (Saint-Auban, France), is dedicated to soft X-ray microscopy. The beamline combines two complementary microscopy methods: XPEEM (X-ray Photo Emitted Electron Microscopy) and STXM (Scanning Transmission X-ray Microscopy) with an aim to reach spatial resolution below 20 nm and to fully exploit the local spectroscopic capabilities of the two microscopes. The availability of the two methods within the same beamline enables the users to select the appropriate approach to study their specific case in terms of sample environment, spectroscopy methods, probing depth etc. In this paper a general description of the beamline and its design are presented. The performance and specifications of the beamline will be reviewed in detail. Moreover, the article is aiming to demonstrate how the beamline performances have been specifically optimized to fulfill the specific requirements of a soft X-ray microscopy beamline in terms of flux, resolution, beam size etc. Special attention has been dedicated to overcome some limiting and hindering problems that are usually encountered on soft X-ray beamlines such as carbon contamination, thermal stability and spectral purity.

  2. X-Ray Polarization Measurements with the EXIST Hard X-Ray Survey Telescope

    Science.gov (United States)

    Krawczynski, Henric; Garson, A., III; Hong, J.; Grindlay, J. E.

    2009-01-01

    The Energetic X-ray Imaging Survey Telescope (EXIST) is a proposed NASA mission for scanning the entire sky in intermediate and hard X-rays. The EXIST mission includes a wide field of view High Energy Telescope (HET) covering the 5-600 keV energy range, and an infrared telescope. The HET has the capability to measure the energy dependent X-ray polarization properties of moderately bright and bright X-ray sources. Here we report on a study of the polarization sensitivity of EXIST as a function of the integration time. Broadband X-ray polarization measurements with EXIST have the potential to make important contributions to our understanding of a number of astrophysical source types including binary black holes, accreting neutron stars, magnetars, pulsar wind nebulae, active galactic nuclei and gamma-ray bursts. EXIST observations of the X-rays from binary black holes can be used to constrain the spins of black holes. Last but not least, EXIST observations of active galactic nuclei and gamma-ray bursts can be used for extremely sensitive Lorentz Invariance tests.

  3. X-ray bursts observed with JEM-X

    DEFF Research Database (Denmark)

    Brandt, Søren Kristian; Chenevez, Jérôme; Lund, Niels

    2006-01-01

    We report on the search for X-ray bursts in the JEM-X X-ray monitor on INTEGRAL during the first two years of operations. More than 350 bursts from 25 different type-I X-ray burst sources were found.......We report on the search for X-ray bursts in the JEM-X X-ray monitor on INTEGRAL during the first two years of operations. More than 350 bursts from 25 different type-I X-ray burst sources were found....

  4. A soft X-ray image of the moon

    Science.gov (United States)

    Schmitt, J. H. M. M.; Aschenbach, B.; Hasinger, G.; Pfeffermann, E.; Snowden, S. L.

    1991-01-01

    A soft X-ray image of the moon obtained by the Roentgen Observatory Satellite ROSAT clearly shows a sunlit crescent, demonstrating that the moon's X-ray luminosity arises from backscattering of solar X-rays. The moon's optically dark side is also X-ray dark, and casts a distinct shadow on the diffuse cosmic X-ray background. Unexpectedly, the dark side seems to emit X-rays at a level about one percent of that of the bright side; this emission very probably results from energetic solar-wind electrons striking the moon's surface.

  5. X-ray radiography for container inspection

    Science.gov (United States)

    Katz, Jonathan I [Clayton, MO; Morris, Christopher L [Los Alamos, NM

    2011-06-07

    Arrangements of X-ray inspection systems are described for inspecting high-z materials in voluminous objects such as containers. Inspection methods may involve generating a radiographic image based on detected attenuation corresponding to a pulsed beams of radiation transmitted through a voluminous object. The pulsed beams of radiation are generated by a high-energy source and transmitted substantially downward along an incident angle, of approximately 1.degree. to 30.degree., to a vertical axis extending through the voluminous object. The generated radiographic image may be analyzed to detect on localized high attenuation representative of high-z materials and to discriminate high-z materials from lower and intermediate-z materials on the basis of the high density and greater attenuation of high-z material for higher energy (3-10 MeV) X-rays, and the compact nature of threatening masses of fissionable materials.

  6. Soft X-ray multilayers and filters

    CERN Document Server

    Wang Zhan Shan; Tang Wei Xing; Qin Shuji; Zhou Bing; Chen Ling Ya

    2002-01-01

    The periodic and non-periodic multilayers were designed by using a random number to change each layer and a suitable merit function. Ion beam sputtering and magnetron sputtering were used to fabricate various multilayers and beam splitters in soft X-ray range. The characterization of multilayers by small angle X-ray diffraction, Auger electron spectroscopy, Rutherford back scattering spectroscopy and reflectivity illustrated the multilayers had good structures and smooth interlayers. The reflectivity and transmission of a beam splitter is about 5%. The fabrication and transmission properties of Ag, Zr were studied. The Rutherford back scattering spectroscopy and auger electron spectroscopy were used to investigate the contents and distributions of impurities and influence on qualities of filters. The attenuation coefficients were corrected by the data obtained by measurements

  7. Neutron and X-ray Spectroscopy

    CERN Document Server

    Hippert, Françoise; Hodeau, Jean Louis; Lelièvre-Berna, Eddy; Regnard, Jean-René

    2006-01-01

    Neutron and X-Ray Spectroscopy delivers an up-to-date account of the principles and practice of inelastic and spectroscopic methods available at neutron and synchrotron sources, including recent developments. The chapters are based on a course of lectures and practicals (the HERCULES course) delivered to young scientists who require these methods in their professional careers. Each chapter, written by a leading specialist in the field, introduces the basic concepts of the technique and provides an overview of recent work. This volume, which focuses on spectroscopic techniques in synchrotron radiation and inelastic neutron scattering, will be a primary source of information for physicists, chemists and materials scientists who wish to acquire a basic understanding of these techniques and to discover the possibilities offered by them. Emphasizing the complementarity of the neutron and X-ray methods, this tutorial will also be invaluable to scientists already working in neighboring fields who seek to extend thei...

  8. X-Ray Polarimetry with GEMS

    Science.gov (United States)

    Strohmayer, Tod

    2011-01-01

    The polarization properties of cosmic X-ray sources are still largely unexplored. The Gravity and Extreme Magnetism SMEX (GEMS) will carry out the first sensitive X-ray polarization survey of a wide range of sources including; accreting compact objects (black holes and neutron stars), AGN, supernova remnants, magnetars and rotation-powered pulsars. GEMS employs grazing-incidence foil mirrors and novel time-projection chamber (TPC) polarimeters leveraging the photoelectric effect to achieve high polarization sensitivity in the 2 - 10 keV band. I will provide an update of the project status, illustrate the expected performance with several science examples, and provide a brief overview of the data analysis challenges

  9. High precision x ray lithographic masks

    Science.gov (United States)

    Pease, R. F.; Browning, R.

    1992-09-01

    This contract period was first concerned with winding up the projects on the embedded X-ray Mask structure and on the 'quantum lithography' idea. As a result of developments elsewhere it became clear that among the most critical issues in achieving high precision X-ray masks were those associated with achieving high precision in both feature size and feature placement in electron beam lithography. Most of the effort in this reporting period was aimed at achieving precision in feature size; notably an attack on the problem of proximity effects. There were two approaches: (1) A short term approach aimed at correcting effects in existing electron beam pattern generators (notably the ETEC MEBES 3 and 4) for feature sizes down 500 nm; and (2) A long term approach aimed at avoiding proximity effects by employing low energy electron exposure for feature size below 500 nm.

  10. X-ray Winds from Black Holes

    Science.gov (United States)

    Miller, Jon M.

    2017-08-01

    Across the mass scale, high-resolution X-ray spectroscopy has transformed our view of accretion onto black holes. The ionized disk winds observed from stellar-mass black holes may sometimes eject more mass than is able to accrete onto the black hole. It is possible that these winds can probe the fundamental physics that drive disk accretion. The most powerful winds from accretion onto massive black holes may play a role in feedback, seeding host bulges with hot gas and halting star formation. The lessons and techniques emerging from these efforts can also reveal the accretion flow geometry in tidal disruption events (TDEs), an especially rich discovery space. This talk will review some recent progress enabled by high-resolution X-ray spectroscopy, and look at the potential of gratings spectrometers and microcalorimeters in the years ahead.

  11. The microchannel x-ray telescope status

    Science.gov (United States)

    Götz, D.; Meuris, A.; Pinsard, F.; Doumayrou, E.; Tourrette, T.; Osborne, J. P.; Willingale, R.; Sykes, J. M.; Pearson, J. F.; Le Duigou, J. M.; Mercier, K.

    2016-07-01

    We present design status of the Microchannel X-ray Telescope, the focussing X-ray telescope on board the Sino- French SVOM mission dedicated to Gamma-Ray Bursts. Its optical design is based on square micro-pore optics (MPOs) in a Lobster-Eye configuration. The optics will be coupled to a low-noise pnCCD sensitive in the 0.2{10 keV energy range. With an expected point spread function of 4.5 arcmin (FWHM) and an estimated sensitivity adequate to detect all the afterglows of the SVOM GRBs, MXT will be able to provide error boxes smaller than 60 (90% c.l.) arc sec after five minutes of observation.

  12. Two-channel X-ray reflectometer

    CERN Document Server

    Touryanski, A G; Pirshin, I V

    2000-01-01

    The two-channel X-ray reflectometer is proposed providing an increase in accuracy and sensitivity especially to nanoscale oxide layers. The reflectometer has two independent measuring channels controlled by a processor and the beam-splitting and spectral selection device based on a row of semitransparent plates of pyrolitic graphite. Results of reflection curve measurements in a relative mode are presented for an Ni film and GaAs monocrystal.

  13. X-ray microimaging by diffractive techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kirz, Janos; Jacobsen, Chris

    2001-07-31

    The report summarizes the development of soft x-ray microscopes at the National Synchrotron Light Source X-1A beamline. We have developed a soft x-ray microscopy beamline (X-1A) at the National Synchrotron Light Source at Brookhaven National Laboratory. This beamline has been upgraded recently to provide two endstations dedicated to microscopy experiments. One endstation hosts a brand new copy of the redesigned room temperature scanning x-ray microscope (STXM), and the other end station hosts a cryo STXM and the original redesigned room temperature microscope, which has been commissioned and has started operation. Cryo STXM and the new microscope use the same new software package, running under the LINUX operating system. The new microscope is showing improved image resolution and extends spectromicroscopy to the nitrogen, oxygen and iron edges. These microscopes are used by us, and by users of the facility, to image hydrated specimens at 50 nm or better spatial resolution and with 0.1-0.5 eV energy resolution. This allows us to carry out chemical state mapping in biological, materials science, and environmental and colloidal science specimens. In the cryo microscope, we are able to do chemical state mapping and tomography of frozen hydrated specimens, and this is of special importance for radiation-sensitive biological specimens. for spectromicroscopic analysis, and methods for obtaining real-space images from the soft x-ray diffraction patterns of non-crystalline specimens. The user program provides opportunities for collaborators and other groups to exploit the techniques available and to develop them further. We have also developed new techniques such as an automated method for acquiring ''stacks'' of images.

  14. Axion mass limits from pulsar x rays

    Energy Technology Data Exchange (ETDEWEB)

    Morris, D.E.

    1984-12-01

    Axions thermally emitted by a neutron star would be converted into x rays in the strong magnetic field surrounding the star. An improvement in the observational upper limit of pulsed x rays from the Vela pulsar (PSR 0833-45) by a factor of 12 would constrain the axion mass M/sub a/ < 2 x 10/sup -3/eV if the core is non-superfluid and at temperature T/sub c/ greater than or equal to 2 x 10/sup 8/K. If the core is superfluid throughout, an improvement factor of 240 would be needed to provide the same constraint on the axion mass, while in the absence of superfluidity, an improvement factor of 200 could constrain M/sub a/ < 6 x 10/sup -4/eV. A search for modulated hard x rays from PSR 1509-58 or other young pulsars at presently attainable sensitivities may enable the setting of an upper limit for the axion mass. Observation of hard x rays from a very young hot pulsar with T/sub c/ greater than or equal to 7 x 10/sup 8/K could set a firm bound on the axion mass, since neutron superfluidity is not expected above this temperature. The remaining axion mass range 6 x 10/sup -4/eV > M/sub a/ > 10/sup -5/eV (the cosmological lower bound) can be covered by an improved Sikivie type laboratory cavity detector for relic axions constituting the galactic halo. 48 refs.

  15. Early x-ray diagnosis of coxarthrosis

    Energy Technology Data Exchange (ETDEWEB)

    Lingg, G.; Nebel, G.

    Radiological and pathological comparisons on specimen of femur head and neck at autopsy have shown a statistical relationship between osteophytosis of the femoral head and ulcerations of the joint cartilage. Especially, there are highly significant relationships between the length of osteophytes and the diameter of the ulcera. The 'plaque'-sign is shown to be a very sensitive indicator of early arthrosis. So there exist semiquantitative parameters for the X-ray diagnosis of early coxarthrosis.

  16. Clustering of X-Ray-Selected AGN

    Directory of Open Access Journals (Sweden)

    N. Cappelluti

    2012-01-01

    that galaxy mergers may constitute the main AGN-triggering mechanism. However, detailed analysis of observational data, acquired with modern telescopes, and the use of the new halo occupation formalism has revealed that the triggering of an AGN could also be attributed to phenomena-like tidal disruption or disk instability and to galaxy evolution. This paper reviews results from 1988 to 2011 in the field of X-ray-selected AGN clustering.

  17. Monitoring Instrument for X-Ray Box

    CERN Document Server

    Cifuentes Ospina, Alberto; Kuehn, Susanne; Schaepe, Steffen; CERN. Geneva. EP Department

    2017-01-01

    A humidity and temperature readout instrument has been designed and implemented in order to monitor the X-Ray Box used for testing the silicon detectors prototypes of the ITk. The sensors are connected to an Arduino Mega board equipped with 16 analog inputs and a serial port to a computer. A user-friendly software has been also designed in order to give an easy access to all measurements.

  18. Basic of X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Giacovazzo, C. [Bari Univ. (Italy). Dip. Geomineralogico

    1996-09-01

    The basic concepts of X-ray diffraction may be more easily understood if it is made preliminary use of a mathematical background. In these pages the authors will first define the delta function and its use for the representation of a lattice. Then the concepts of Fourier transform and convolution are given. At the end of this talk one should realize that a crystal is the convolution of the lattice with a function representing the content of the unit cell.

  19. Wide band focusing x-ray spectrograph with spatial resolution.

    Science.gov (United States)

    Pikuz, S A; Douglass, J D; Shelkovenko, T A; Sinars, D B; Hammer, D A

    2008-01-01

    A new, wide spectral bandwidth x-ray spectrograph, the wide-bandwidth focusing spectrograph with spatial resolution (WB-FSSR), based on spherically bent mica crystals, is described. The wide bandwidth is achieved by combining three crystals to form a large aperture dispersive element. Since the WB-FSSR covers a wide spectral band, it is very convenient for application as a routine diagnostic tool in experiments in which the desired spectral coverage is different from one test to the next. The WB-FSSR has been tested in imploding wire-array experiments on a 1 MA pulsed power machine, and x-ray spectra were recorded in the 1-20 A spectral band using different orders of mica crystal reflection. Using a two mirror-symmetrically placed WB-FSSR configuration, it was also possible to distinguish between a real spectral shift and a shift of recorded spectral lines caused by the spatial distribution of the radiating plasma. A spectral resolution of about 2000 was demonstrated and a spatial resolution of approximately 100 microm was achieved in the spectral band of 5-10 A in second order of mica reflection. A simple method of numerical analysis of spectrograph capability is proposed.

  20. X-ray computed tomography applied to investigate ancient manuscripts

    Science.gov (United States)

    Bettuzzi, Matteo; Albertin, Fauzia; Brancaccio, Rosa; Casali, Franco; Pia Morigi, Maria; Peccenini, Eva

    2017-03-01

    I will describe in this paper the first results of a series of X-ray tomography applications, with different system setups, running on some ancient manuscripts containing iron-gall ink. The purpose is to verify the optimum measurement conditions with a laboratory instrumentation -that is also in fact portable- in order to recognize the text from the inside of the documents, without opening them. This becomes possible by exploiting the X-rays absorption contrast of iron-based ink and the three-dimensional reconstruction potential provided by computed tomography that overcomes problems that appear in simple radiograph practice. This work is part of a larger project of EPFL (Ecole Polytechnique Fédérale de Lausanne, Switzerland), the "Venice Time Machine" project (EPEL, Digital Heritage Venice, http://dhvenice.eu/, 2015) aimed at digitizing, transcribing and sharing in an open database all the information of the State Archives of Venice, exploiting traditional digitization technologies and innovative methods of acquisition. In this first measurement campaign I investigated a manuscript of the seventeenth century made of a folded sheet; a couple of unopened ancient wills kept in the State Archives in Venice and a handwritten book of several hundred pages of notes of Physics of the nineteenth century.

  1. The research of mandibular foramen in panorex X-ray.

    Science.gov (United States)

    Jalili, Mohammad Reza

    2010-11-01

    In the present investigation position of mandibular foramen of the mandible in relation to other landmarks were studied. Panoramic x-ray of 103 females and 94 males who come to above mentioned clinic selected by available sampling. All samples were Iranian with the age above 18 years old. X-ray machine and method were same for all samples. Special landmarks in right side of mandible were identified and their distance from mandibular foramen were recorded by millimetric ruler. The measured landmarks were as follow: Mandibular angle, Coronoid process, Mandibular notch, Head of mandible, Posterior border of ramus of mandible, Anterior border of the ramus, External oblique line, Mylohyoid line, Occlusal plane: mandibular angle were measured by protractor. Results between male and female were compared by Mann Whitney U test. The average of both sexes ages were 34.7 years. Difference between distance of mandibular foramen from following landmarks between male and females were significant: (1) Mandibular angle, (2) Head of mandible, (3) Posterior border of ramus, (4) Mylohyoid and (5) Occlusal plane. Present investigation revealed position variation of M.F. in relation to other landmarks and differences between male and female, we suggest kind of investigation individual under 18 years old.

  2. X-ray nanoprobe project at Taiwan Photon Source

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Gung-Chian, E-mail: gcyin@nsrrc.org.tw; Chang, Shih-Hung; Chen, Bo-Yi; Chen, Huang-Yeh; Lin, Bi-Hsuan; Tseng, Shao-Chin; Lee, Chien-Yu; Wu, Jian-Xing; Tang, Mau-Tsu [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Wu, Shao-Yun [National Tsing-Hua University, Hsinchu 30076, Taiwan (China)

    2016-07-27

    The hard X-ray nanoprobe facility at Taiwan Photon Source (TPS) provides versatile X-ray analysis techniques, with tens of nanometer resolution, including XRF, XAS, XEOL, projection microscope, CDI, etc. Resulting from the large numerical aperture obtained by utilizing Montel KB mirrors, the beamline with a moderate length 75 meters can conduct similar performance with those beamlines longer than 100 meters. The two silica-made Montel mirrors are 45 degree cut and placed in a V-shape to eliminate the gap loss and the deformation caused by gravity. The slope error of the KB mirror pair is less than 0.04 µrad accomplished by elastic emission machining (EEM) method. For the beamline, a horizontal DCM and two-stage focusing in horizontal direction is applied. For the endstation, a combination of SEM for quickly positioning the sample, a fly scanning system with laser interferometers, a precise temperature control system, and a load lock transfer system will be implemented. In this presentation, the design and construction progress of the beamline and endstation is reported. The endstation is scheduled to be in commissioning phase in 2016.

  3. Doses Received by Patients during Thorax X-Ray Examinations

    Directory of Open Access Journals (Sweden)

    Nsikan U. Esen

    2013-03-01

    Full Text Available Introduction Radiation exposures from diagnostic medical examinations are generally low and are almost always justified by the benefits of accurate diagnosis of possible disease conditions. Therefore, entrance skin dose (ESD, body organ dose (BOD, and effective dose (ED from adult patients undergoing routine thorax posterior-anterior (PA and thorax right lateral (RLAT were estimated in University Hospital, Port Harcourt, Southern Nigeria. Materials and Methods Totally, 102 patients were considered in this work. Using software packages to carry out ESD, BOD, and ED is a recent resource in dosimetry and is being widely used in hospitals. The software used in this work was  CALDose_X 5.0. The software makes use of the technical exposure parameters and the tube output of the X-ray machine. Results The estimated ESD median values were 0.96 and 1.85 mGy for thorax posterior anterior (PA and right lateral (RLAT, respectively. The highest BOD was in the adrenals (270 µGy for thorax PA and Liver (263 µGy for thorax RLAT. Similarly, ED for thorax PA and RLAT examination were 0.068 and 0.107 mGy, respectively. Conclusion It could be observed that examinations that imparted the highest ESD were thorax PA when compared with the established dose level. Therefore, these results call for quality assurance program (QAP in diagnostic X-ray units in Nigeria hospitals.

  4. The X-ray Telescope of CAST

    CERN Document Server

    Kuster, M.; Cebrian, S.; Davenport, M.; Elefteriadis, C.; Englhauser, J.; Fischer, H.; Franz, J.; Friedrich, P.; Hartmann, R.; Heinsius, F.H.; Hoffmann, D.H.H.; Hoffmeister, G.; Joux, J.N.; Kang, D.; Konigsmann, Kay; Kotthaus, R.; Papaevangelou, T.; Lasseur, C.; Lippitsch, A.; Lutz, G.; Morales, J.; Rodriguez, A.; Struder, L.; Vogel, J.; Zioutas, K.

    2007-01-01

    The Cern Axion Solar Telescope (CAST) is in operation and taking data since 2003. The main objective of the CAST experiment is to search for a hypothetical pseudoscalar boson, the axion, which might be produced in the core of the sun. The basic physics process CAST is based on is the time inverted Primakoff effect, by which an axion can be converted into a detectable photon in an external electromagnetic field. The resulting X-ray photons are expected to be thermally distributed between 1 and 7 keV. The most sensitive detector system of CAST is a pn-CCD detector combined with a Wolter I type X-ray mirror system. With the X-ray telescope of CAST a background reduction of more than 2 orders off magnitude is achieved, such that for the first time the axion photon coupling constant g_agg can be probed beyond the best astrophysical constraints g_agg < 1 x 10^-10 GeV^-1.

  5. X-raying galaxies: a Chandra legacy.

    Science.gov (United States)

    Wang, Q Daniel

    2010-04-20

    This presentation reviews Chandra's major contribution to the understanding of nearby galaxies. After a brief summary on significant advances in characterizing various types of discrete x-ray sources, the presentation focuses on the global hot gas in and around galaxies, especially normal ones like our own. The hot gas is a product of stellar and active galactic nuclear feedback--the least understood part in theories of galaxy formation and evolution. Chandra observations have led to the first characterization of the spatial, thermal, chemical, and kinetic properties of the gas in our galaxy. The gas is concentrated around the galactic bulge and disk on scales of a few kiloparsec. The column density of chemically enriched hot gas on larger scales is at least an order magnitude smaller, indicating that it may not account for the bulk of the missing baryon matter predicted for the galactic halo according to the standard cosmology. Similar results have also been obtained for other nearby galaxies. The x-ray emission from hot gas is well correlated with the star formation rate and stellar mass, indicating that the heating is primarily due to the stellar feedback. However, the observed x-ray luminosity of the gas is typically less than a few percent of the feedback energy. Thus the bulk of the feedback (including injected heavy elements) is likely lost in galaxy-wide outflows. The results are compared with simulations of the feedback to infer its dynamics and interplay with the circumgalactic medium, hence the evolution of galaxies.

  6. Healing X-ray scattering images.

    Science.gov (United States)

    Liu, Jiliang; Lhermitte, Julien; Tian, Ye; Zhang, Zheng; Yu, Dantong; Yager, Kevin G

    2017-07-01

    X-ray scattering images contain numerous gaps and defects arising from detector limitations and experimental configuration. We present a method to heal X-ray scattering images, filling gaps in the data and removing defects in a physically meaningful manner. Unlike generic inpainting methods, this method is closely tuned to the expected structure of reciprocal-space data. In particular, we exploit statistical tests and symmetry analysis to identify the structure of an image; we then copy, average and interpolate measured data into gaps in a way that respects the identified structure and symmetry. Importantly, the underlying analysis methods provide useful characterization of structures present in the image, including the identification of diffuse versus sharp features, anisotropy and symmetry. The presented method leverages known characteristics of reciprocal space, enabling physically reasonable reconstruction even with large image gaps. The method will correspondingly fail for images that violate these underlying assumptions. The method assumes point symmetry and is thus applicable to small-angle X-ray scattering (SAXS) data, but only to a subset of wide-angle data. Our method succeeds in filling gaps and healing defects in experimental images, including extending data beyond the original detector borders.

  7. Healing X-ray scattering images

    Directory of Open Access Journals (Sweden)

    Jiliang Liu

    2017-07-01

    Full Text Available X-ray scattering images contain numerous gaps and defects arising from detector limitations and experimental configuration. We present a method to heal X-ray scattering images, filling gaps in the data and removing defects in a physically meaningful manner. Unlike generic inpainting methods, this method is closely tuned to the expected structure of reciprocal-space data. In particular, we exploit statistical tests and symmetry analysis to identify the structure of an image; we then copy, average and interpolate measured data into gaps in a way that respects the identified structure and symmetry. Importantly, the underlying analysis methods provide useful characterization of structures present in the image, including the identification of diffuse versus sharp features, anisotropy and symmetry. The presented method leverages known characteristics of reciprocal space, enabling physically reasonable reconstruction even with large image gaps. The method will correspondingly fail for images that violate these underlying assumptions. The method assumes point symmetry and is thus applicable to small-angle X-ray scattering (SAXS data, but only to a subset of wide-angle data. Our method succeeds in filling gaps and healing defects in experimental images, including extending data beyond the original detector borders.

  8. Active Galactic Nuclei and X-ray Ovservations

    Science.gov (United States)

    Vasylenko, A. A.; Zhdanov, V. I.; Fedorova, E. V.

    2016-11-01

    Active galactic nuclei (AGN) are the brightest objects in the Universe and their brightness is mainly caused by accretion of m atter onto supermassive black holes (SMBH). This is the common reason of the AGN activity. However, every AGN has differences and fine features, which are the subject of an intensive investigation. The occurrence of such highly-relativistic objects as SMBH residing at the AGN core makes them an excellent laboratory for testing the fundamental physical theories. The X-rays and gamma-rays generated in a corona of an accretion disc around SMBH yield valuable information for these tests, the radiation in the range of 1-100 keV being at present the most informative source. However, there are a number of obstacles for such a study due to different physical processes that complicate the interpretation of observations in different bands of the electromagnetic radiation. In this paper, we review the current concepts concerning the structure of AGNs with a focus on the central part of these objects th at require relativistic theories for their understanding. The basic notions of the unified AGN schemes are considered; some modifications are reviewed. The paper contains the following sections. I. Introduction; II. Observational manifestations and classification of galaxies with active nuclei (II.A. Optical observations; II.B. Radio observations; II.C. X-ray data; II.D Infrared data; II.E. AGN anatomy with multywave data); III. AGN "central machine"; III.A. Black holes; III.B. Accretion disc types; III.C. Corona; III.D. AGN unified scheme); IV. Simulation X-ray AGN spectra (IV.A. The power-law contimuum and the exponential cut-off; IV.B. The absorption of X-rays; IV.C. Reflection; IV.D. Fe K a line; IV.E. Spin paradigm); V. AGN as a laboratory to test the fundamental interactions (V.A. Strong gravitational fields; V.B. Dynamic dark energy near compact astrophysical objects

  9. Reabsorption of soft x-ray emission at high x-ray free-electron laser fluences.

    Science.gov (United States)

    Schreck, Simon; Beye, Martin; Sellberg, Jonas A; McQueen, Trevor; Laksmono, Hartawan; Kennedy, Brian; Eckert, Sebastian; Schlesinger, Daniel; Nordlund, Dennis; Ogasawara, Hirohito; Sierra, Raymond G; Segtnan, Vegard H; Kubicek, Katharina; Schlotter, William F; Dakovski, Georgi L; Moeller, Stefan P; Bergmann, Uwe; Techert, Simone; Pettersson, Lars G M; Wernet, Philippe; Bogan, Michael J; Harada, Yoshihisa; Nilsson, Anders; Föhlisch, Alexander

    2014-10-10

    We report on oxygen K-edge soft x-ray emission spectroscopy from a liquid water jet at the Linac Coherent Light Source. We observe significant changes in the spectral content when tuning over a wide range of incident x-ray fluences. In addition the total emission yield decreases at high fluences. These modifications result from reabsorption of x-ray emission by valence-excited molecules generated by the Auger cascade. Our observations have major implications for future x-ray emission studies at intense x-ray sources. We highlight the importance of the x-ray pulse length with respect to the core-hole lifetime.

  10. Development of a Direct Fabrication Technique for Full-Shell X-Ray Optics

    Science.gov (United States)

    Gubarev, M.; Kolodziejczak, J. K.; Griffith, C.; Roche, J.; Smith, W. S.; Kester, T.; Atkins, C.; Arnold, W.; Ramsey, B.

    2016-01-01

    Future astrophysical missions will require fabrication technology capable of producing high angular resolution x-ray optics. A full-shell direct fabrication approach using modern robotic polishing machines has the potential for producing high resolution, light-weight and affordable x-ray mirrors that can be nested to produce large collecting area. This approach to mirror fabrication, based on the use of the metal substrates coated with nickel phosphorous alloy, is being pursued at MSFC. The design of the polishing fixtures for the direct fabrication, the surface figure metrology techniques used and the results of the polishing experiments are presented.

  11. A Review of X-ray Free-Electron Laser Theory

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhirong; /SLAC; Kim, Kwang-Je; /ANL, APS

    2006-12-18

    High-gain free-electron lasers (FELs) are being developed as extremely bright sources for a next-generation x-ray facility. In this paper, we review the basic theory of the startup, the exponential growth, and the saturation of the high-gain process, emphasizing the self-amplified spontaneous emission (SASE). The radiation characteristics of an x-ray FEL, including its transverse coherence, temporal characteristics, and harmonic content, are discussed. FEL performance in the presence of machine errors and undulator wakefields is examined. Various enhancement schemes through seeding and beam manipulations are summarized.

  12. Karl Jaspers' phenomenology in the light of histological and X-ray metaphors.

    Science.gov (United States)

    Vlasova, Olga Alexandrovna; Beveridge, Allan

    2014-03-01

    The study considers the origins of Karl Jaspers' phenomenology. What did phenomenology mean to Jaspers and what was his personal perspective? What metaphors did he associate with it? This paper describes his phenomenological method by using the metaphors of histology and the X-ray. This perspective enables a better understanding, not only of the origins and essence of his phenomenology but also of its value for Jaspers himself. In Jaspers' daily life, he would have been familiar with microscopes and X-ray machines.

  13. K-Edge Subtraction Angiography with Synchrotron X-Rays

    CERN Document Server

    Giacomini, J C

    1996-01-01

    The purpose of this project was to utilize dual energy, monochromatic X-rays produced from synchrotrons radiation in order to obtain noninvasive medical imaging. The application of synchrotrons radiation to medical imaging is based on the principle of iodine dichromography, first described by Bertil Jacobson of the Karolinska Institute in 1953. Medical imaging using synchrotrons radiation and K-edge dichromography was pioneered at Stanford University under the leadership of Dr. Ed Rubenstein, and the late Nobel Laureate in Physics, Dr. Robert Hofstadter. With progressive refinements in hardware, clinical-quality images were obtained of human coronary arteries utilizing peripheral injections of iodinated contrast agent. These images even now are far superior to those being presented by investigators using MRI as an imaging tool for coronary arteries. However, new supplies and instruments in the cardiac catheterization laboratory have served to transform coronary angiography into an outpatient procedure, with r...

  14. Occupational exposure to medical X rays in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Jankowski, J.; Nowak, B.; Liniecki, J. (Inst. of Occupational Medicine, Lodz (Poland))

    1991-01-01

    Personal dosimetry in Poland indicates that exposure to X rays of workers engaged in surgical radiology is higher than that among other radiologists and auxiliary personnel, 0.9 as against 0.4 mSv per annum. This information, however, does not provide detailed insight into the exposures. To study this problem, the exposure of personnel employed in operating theatres and utilising fluoroscopy was investigated. With TL dosemeters, the distribution of doses to the body was measured on the surface of protective aprons and on the forehead, the wrist and the shoulder. The study embraced 20 centres in Poland engaged in cardiac pacemaker insertion, haemodynamic examinations of the heart, transcutaneous removal of kidney stones, radiological control of biliary routes and orthopaedic surgery. The results enable one to assess the average annual effective dose equivalent H{sub E} for workers and the corresponding dose equivalents H to the lens of the eye and the hands. (author).

  15. The hard X-ray perspective on the soft X-ray excess

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevan, Ranjan V.; Mushotzky, Richard F.; Reynolds, Christopher S.; Lohfink, Anne M.; Zoghbi, Abderahmen [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Fabian, Andrew C. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Gallo, Luigi C. [Department of Astronomy and Physics, Saint Mary' s University, 923 Robie Street, Halifax, Nova Scotia B3H 3C3 (Canada); Walton, Dominic, E-mail: ranjan@astro.umd.edu [Cahill Centre for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States)

    2014-04-10

    The X-ray spectra of many active galactic nuclei exhibit a 'soft excess' below 1 keV, whose physical origin remains unclear. Diverse models have been suggested to account for it, including ionized reflection of X-rays from the inner part of the accretion disk, ionized winds/absorbers, and Comptonization. The ionized reflection model suggests a natural link between the prominence of the soft excess and the Compton reflection hump strength above 10 keV, but it has not been clear what hard X-ray signatures, if any, are expected from the other soft X-ray candidate models. Additionally, it has not been possible up until recently to obtain high-quality simultaneous measurements of both soft and hard X-ray emission necessary to distinguish these models but upcoming joint XMM-NuSTAR programs provide precisely this opportunity. In this paper, we present an extensive analysis of simulations of XMM-NuSTAR observations, using two candidate soft excess models as inputs, to determine whether such campaigns can disambiguate between them by using hard and soft X-ray observations in tandem. The simulated spectra are fit with the simplest 'observer's model' of a blackbody and neutral reflection to characterize the strength of the soft and hard excesses. A plot of the strength of the hard excess against the soft excess strength provides a diagnostic plot which allows the soft excess production mechanism to be determined in individual sources and samples using current state-of-the-art and next generation hard X-ray enabled observatories. This approach can be straightforwardly extended to other candidate models for the soft excess.

  16. X-Rays: MedlinePlus Health Topic

    Science.gov (United States)

    ... Do I Need X-Rays? (Academy of General Dentistry) Videos and Tutorials Chest X-Ray (American College ... of Radiologic Technologists) - PDF - In English and Spanish Pediatric Voiding Cystourethrogram (American College of Radiology, Radiological Society ...

  17. Exploration of Monoenergetic X-Ray Mammography with Syncrotron Radiation

    National Research Council Canada - National Science Library

    Johnston, Richard

    1998-01-01

    .... Specifically developed as part of our x-ray mammography program utilizing monochromatic x-rays from a synchrotron source, this technique has produced images of test objects and tissue whose contrast...

  18. Improved intensifying screen reduces X-ray exposure

    Science.gov (United States)

    Buchanan, R. A.

    1972-01-01

    X-ray intensifying screen may make possible radiographic procedures where detection speed and X-ray tube power have been the limiting factors. Device will reduce total population exposure to harmful radiation in the United States.

  19. Improving Object Classification in X-ray Luggage Inspection

    OpenAIRE

    SHI, XINHUA

    2000-01-01

    X-ray detection methods have increasingly been used as an effective means for the automatic detection of explosives. While a number of devices are now commercially available, most of these technologies are not yet mature. The purpose of this research has been to investigate methods for using x-ray dual-energy transmission and scatter imaging technologies more effectively. Followed by an introduction and brief overview of x-ray detection technologies, a model for a prototype x-ray scanning ...

  20. Laser Holder Aids Centering of X-Ray Head

    Science.gov (United States)

    Bulthuis, D. V.; Kettering, D. D.

    1986-01-01

    Laser holder used when alining X-ray head makes procedure safer and more reliable. Laser holder assembly attached to X-ray head to enable head to be alined optically before X-ray exposure. When laser in operating position laser beam shines on spot later illuminated with X-rays. New holder grips laser securely, maintains alinement, does not interfere with head placement, and requires only one 110-V power cord.

  1. Ultrashort X-ray pulse generation using subpicosecond electron linac

    CERN Document Server

    Harano, H; Yoshii, K; Ueda, T; Okita, S; Uesaka, M

    2000-01-01

    As a promising tool for ultrafast material analyses, we propose to utilize the X-ray pulse which may be generated in a quite simple manner using subpicosecond electron linacs. The properties of the X-ray were numerically studied with the EGS4 code. Verification of the X-ray generation was also conducted at the Nuclear Engineering Research Laboratory (NERL) linac and clear diffraction patterns of characteristic X-ray were obtained for typical single crystals.

  2. Fabricating High-Resolution X-Ray Collimators

    Science.gov (United States)

    Appleby, Michael; Atkinson, James E.; Fraser, Iain; Klinger, Jill

    2008-01-01

    A process and method for fabricating multi-grid, high-resolution rotating modulation collimators for arcsecond and sub-arcsecond x-ray and gamma-ray imaging involves photochemical machining and precision stack lamination. The special fixturing and etching techniques that have been developed are used for the fabrication of multiple high-resolution grids on a single array substrate. This technology has application in solar and astrophysics and in a number of medical imaging applications including mammography, computed tomography (CT), single photon emission computed tomography (SPECT), and gamma cameras used in nuclear medicine. This collimator improvement can also be used in non-destructive testing, hydrodynamic weapons testing, and microbeam radiation therapy.

  3. Electrophysiologic and cellular characteristics of cardiomyocytes after X-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Frieß, Johannes L., E-mail: johannes.friess@h-ab.de [University for Applied Sciences Aschaffenburg, biomems lab, Würzburger Straße 45, 63743 Aschaffenburg (Germany); Heselich, Anja [Technische Universität Darmstadt, Developmental Biology and Neurogenetics, Schnittspahnstraße 13, 64287 Darmstadt (Germany); Ritter, Sylvia [Helmholtz Institute for Heavy Ion Research (GSI), Biophysics Department, Planckstraße 1, 64291 Darmstadt (Germany); Haber, Angelina; Kaiser, Nicole; Layer, Paul G. [Technische Universität Darmstadt, Developmental Biology and Neurogenetics, Schnittspahnstraße 13, 64287 Darmstadt (Germany); Thielemann, Christiane [University for Applied Sciences Aschaffenburg, biomems lab, Würzburger Straße 45, 63743 Aschaffenburg (Germany)

    2015-07-15

    Highlights: • Electrophysiologic and cellular effects of X-rays on primary cardiac cell cultures. • X-ray doses between 0.5 and 7 Gy. • Higher beat rate at reduced field action potential durations 7 days after exposure. • More increased cell cycle checkpoint arrest in G2/M than in G1/S phase. • Induced DSBs were mostly repaired within 24 h after irradiation. - Abstract: The aim of this study was to investigate possible effects of ionizing irradiation on the electrophysiological functionality of cardiac myocytes in vitro. Primary chicken cardiomyocytes with spontaneous beating activity were irradiated with X-rays (dose range of 0.5–7 Gy). Functional alterations of cardiac cell cultures were evaluated up to 7 days after irradiation using microelectrode arrays. As examined endpoints, cell proliferation, apoptosis, reactive oxygen species (ROS) and DNA damage were evaluated. The beat rate of the cardiac networks increased in a dose-dependent manner over one week. The duration of single action potentials was slightly shortened. Additionally, we observed lower numbers of mitotic and S-phase cells at certain time points after irradiation. Also, the number of cells with γH2AX foci increased as a function of the dose. No significant changes in the level of ROS were detected. Induction of apoptosis was generally negligibly low. This is the first report to directly show alterations in cardiac electrophysiology caused by ionizing radiation, which were detectable up to one week after irradiation.

  4. X-ray inspection of arduous welds in rocket and space technology with the use of a microfocus X-ray apparatus

    Science.gov (United States)

    Potrakhov, N. N.; Potrakhov, E. N.; Usachev, E. Y.; Gnedin, M. M.; Voroschuk, D. V.; Shavrina, I. M.

    2017-07-01

    The article presents the design of a specialized X-ray machine to perform circumferential weld inspections various structural elements of air and space technology. Shows the main specifications of the device and describes a particular application of the apparatus. The results of the use of the device in conditions of real production on one of the local engine companies in the aircraft and space industry.

  5. High-resolution x-ray characterization of mosaic crystals for hard x-ray astronomy

    Science.gov (United States)

    Ferrari, Claudio; Buffagni, Elisa; Marchini, Laura; Zappettini, Andrea

    2012-04-01

    GaAs, Cu, CdTe, and CdZnTe crystals have been studied as optical elements for lenses for hard x-ray astronomy. High-resolution x-ray diffraction at 8 keV in Bragg geometry and at synchrotron at energies up to 500 keV in Laue geometry has been used. A good agreement was found between the mosaicity evaluated in Bragg geometry at 8 keV with x-ray penetration of the order of few tens of micrometers and that derived at synchrotron in transmission Laue geometry at higher x-ray energies. Mosaicity values in a range between a few to 150 arcsec were found in all the samples but, due to the presence of crystal grains in the cm range, CdTe and CdZnTe crystals were found not suitable. Cu crystals exhibit a mosaicity of the order of several arcmin; they indeed were found to be severely affected by cutting damage which could only be removed with a very deep etching. The full width at half maximum of the diffraction peaks decreased at higher x-ray energies showing that the peak broadening is affected by crystallite size. GaAs crystals grown by Czochralski method showed a mosaic spread up to 30 arcsec and good diffraction efficiency up to energies of 500 keV. The use of thermal treatments as a possible method to increase the mosaic spread was also evaluated.

  6. Characterization of Metalloproteins and Biomaterials by X-ray Absorption Spectroscopy and X-ray Diffraction

    DEFF Research Database (Denmark)

    Frankær, Christian Grundahl

    This thesis presents thework on combining complementary X-rays techniques for studying the structures of proteins and other biomaterials, and consists of three different projects: (i) Characterization of protein powders with X-ray powder diffraction (XRPD). (ii) The combination of X-ray crystallo......This thesis presents thework on combining complementary X-rays techniques for studying the structures of proteins and other biomaterials, and consists of three different projects: (i) Characterization of protein powders with X-ray powder diffraction (XRPD). (ii) The combination of X......, nickel and copper, and their XRD crystal structures were solved to 1.90 Å, 1.50 Å and 1.45 Å resolution, respectively. As the affinity to iron is low, iron insulin crystals were grown in presence of small amounts of zinc. The two metal sites in the XRD structure thus contained respectively one Fe2......+ and one Zn2+ ion, with respectively tetrahedral and octahedral coordination geometry. The metal sites in nickel and copper insulin were studied by XAS. Coordination distances were refined from EXAFS showing a very regular octahedral coordination of Ni2+, which was further verified by calculated XANES...

  7. ``Soft X-ray transient'' outbursts which are not soft

    NARCIS (Netherlands)

    Brocksopp, C.; Bandyopadhyay, R.M.; Fender, R.P.

    2004-01-01

    We have accumulated multiwavelength (X-ray, optical, radio) lightcurves for the eight black hole X-ray binaries which have been observed to enter a supposed `soft X-ray transient' outburst, but remained in the low/hard state throughout the outburst. Comparison of the lightcurve morphologies,

  8. Orbital Evolution Measurement of the Accreting Millisecond X-ray ...

    Indian Academy of Sciences (India)

    powered millisecond X-ray pulsar SAX J1808.4–3658 using. X-ray data obtained during four outbursts of this source. Extensive obser- vations were made with the proportional counter array of the Rossi X-ray. Timing Explorer (RXTE) during the four ...

  9. Digital enhancement of X-rays for NDT

    Science.gov (United States)

    Butterfield, R. L.

    1980-01-01

    Report is "cookbook" for digital processing of industrial X-rays. Computer techniques, previously used primarily in laboratory and developmental research, have been outlined and codified into step by step procedures for enhancing X-ray images. Those involved in nondestructive testing should find report valuable asset, particularly is visual inspection is method currently used to process X-ray images.

  10. 14th International Conference on X-Ray Lasers

    CERN Document Server

    Menoni, Carmen; Marconi, Mario

    2016-01-01

    These proceedings comprise invited and contributed papers presented at the 14th International Conference on X-Ray Lasers (ICXRL 2014). This conference is part of a continuing series dedicated to recent developments and applications of x-ray lasers and other coherent x-ray sources with attention to supporting technologies and instrumentation. New results in the generation of intense, coherent x-rays and progress toward practical devices and their applications in numerous fields are reported. Areas of research in plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generation, and other x-ray generation schemes are covered.  The scope of ICXRL 2014 included, but was not limited to: Laser-pumped X-ray lasers Discharge excitation and other X-ray laser pumping methods Injection/seeding of X-ray amplifiers New lasing transitions and novel X-ray laser schemes High Harmonic sources-Free-electron laser generation in the XUV and X-ray range Novel schemes for coherent XUV and X-ray ge...

  11. X-Rays from Saturn and its Rings

    Science.gov (United States)

    Bhardwaj, Anil; Elsner, Ron F.; Waite, J. Hunter; Gladstone, G. Randall; Cravens, Tom E.; Ford, Peter G.

    2005-01-01

    In January 2004 Saturn was observed by Chandra ACIS-S in two exposures, 00:06 to 11:00 UT on 20 January and 14:32 UT on 26 January to 01:13 UT on 27 January. Each continuous observation lasted for about one full Saturn rotation. These observations detected an X-ray flare from the Saturn's disk and indicate that the entire Saturnian X-ray emission is highly variable -- a factor of $\\sim$4 variability in brightness in a week time. The Saturn X-ray flare has a time and magnitude matching feature with the solar X-ray flare, which suggests that the disk X-ray emission of Saturn is governed by processes happening on the Sun. These observations also unambiguously detected X-rays from Saturn's rings. The X-ray emissions from rings are present mainly in the 0.45-0.6 keV band centered on the atomic OK$\\alpha$ fluorescence line at 525 eV: indicating the production of X-rays due to oxygen atoms in the water icy rings. The characteristics of X-rays from Saturn's polar region appear to be statistically consistent with those from its disk X-rays, suggesting that X-ray emission from the polar cap region might be an extension of the Saturn disk X-ray emission.

  12. On the ultimate x-ray detector for angiography

    NARCIS (Netherlands)

    Slump, Cornelis H.; Flynn, M.J.; Kauffman, J.A.

    2005-01-01

    The purpose of our research is to describe the ultimate X-ray detector for angiography. Angiography is a well established X-ray imaging technique for the examination of blood vessels. Contrast agent is injected followed by X-ray exposures and possible obstructions in the blood vessels can be

  13. Synchrotron radiation X-ray microfluorescence techniques and ...

    Indian Academy of Sciences (India)

    Synchrotron X-ray imaging systems with fluorescence techniques was developed for biomedical researches in Brazilian Synchrotron Laboratory. An X-ray fluorescence microtomography system was implemented to analyse human prostate and breast samples and an X-ray microfluorescence system was implemented to ...

  14. Resonant inelastic x-ray scattering studies of elementary excitations

    NARCIS (Netherlands)

    Ament, Lucas Johannes Peter (Luuk)

    2010-01-01

    Resonant Inelastic X-ray Scattering (RIXS) is an X-ray in, X-ray out technique that enables one to study the dispersion of excitations in solids. In this thesis, we investigated how various elementary excitations of transition metal oxides show up in RIXS spectra.

  15. Resonant x-ray scattering in correlated systems

    CERN Document Server

    Ishihara, Sumio

    2017-01-01

    The research and its outcomes presented here is devoted to the use of x-ray scattering to study correlated electron systems and magnetism. Different x-ray based methods are provided to analyze three dimensional electron systems and the structure of transition-metal oxides. Finally the observation of multipole orderings with x-ray diffraction is shown.

  16. Resonant X-ray scattering in correlated systems

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Youichi [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan). Inst. of Materials Structure Science; Ishihara, Sumio (ed.) [Tohoku Univ., Sendai, Miyagi (Japan). Dept. of Physics

    2017-03-01

    The research and its outcomes presented here is devoted to the use of X-ray scattering to study correlated electron systems and magnetism. Different X-ray based methods are provided to analyze three dimensional electron systems and the structure of transition-metal oxides. Finally the observation of multipole orderings with X-ray diffraction is shown.

  17. X-Ray Exam: Lower Leg (Tibia and Fibula)

    Science.gov (United States)

    ... recorded on a computer or special X-ray film. This image shows the bones (tibia and fibula) and soft tissues of the lower leg. The X-ray image is black and white. Dense structures that block the passage of the X-ray beam through the body, such as the tibia and fibula, appear white ...

  18. Orbital Evolution Measurement of the Accreting Millisecond X-ray ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... We present results from a pulse timing analysis of the accretion-powered millisecond X-ray pulsar SAX J1808.4–3658 using X-ray data obtained during four outbursts of this source. Extensive observations were made with the proportional counter array of the Rossi X-ray Timing Explorer (RXTE) during the ...

  19. Spectroscopic Studies of X-Ray Binary Pulsars

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Abstract. Several new features of X-ray binary pulsars are revealed from recent observations with ASCA, RXTE, BeppoSAX and other X- ray observatories. Among these, I will review in this paper some recent progress in spectroscopic studies of accreting X-ray pulsars in binary sys- tems (XBPs). First, I will discuss soft ...

  20. Improved spatial resolution by MOSFET dosimetry of an x-ray microbeam.

    Science.gov (United States)

    Kaplan, G I; Rosenfeld, A B; Allen, B J; Booth, J T; Carolan, M G; Holmes-Siedle, A

    2000-01-01

    Measurement of the lateral profile of the dose distribution across a narrow x-ray microbeam requires a dosimeter with a micron resolution. We investigated the use of a MOSFET dosimeter in an "edge-on" orientation with the gate insulating oxide layer parallel to the direction of the beam. We compared results using this technique to Gafchromic film measurements of a 200 micrometer wide planar x-ray microbeam. The microbeam was obtained by using a vernier micrometer-driven miniature collimator attached to a Therapax DXT300 x-ray machine operated at 100 kVp. The "edge-on" application allows utilization of the ultra thin sensitive volume of the MOSFET detector. Spatial resolution of both the MOSFET and Gafchromic film dosimeters appeared to be of about 1 micrometer. The MOSFET dosimeter appeared to provide more uniform dose profiles with the advantage of on-line measurements.

  1. Preliminary investigation of changes in x-ray multilayer optics subjected to high radiation flux

    Energy Technology Data Exchange (ETDEWEB)

    Hockaday, M.P.; Blake, R.L.; Grosso, J.S.; Selph, M.M.; Klein, M.M.; Matuska, W. Jr.; Palmer, M.A.; Liefeld, R.J.

    1985-01-01

    A variety of metal multilayers was exposed to high x-ray flux using Sandia National Laboratories' PROTO II machine in the gas puff mode. Fluxes incident on the multilayers above 700 MW/cm/sup 2/ in total radiation, in nominal 20 ns pulses, were realized. The neon hydrogen- and helium-like resonance lines were used to probe the x-ray reflectivity properties of the multilayers as they underwent change of state during the heating pulse. A fluorescer-fiber optic-streak camera system was used to monitor the changes in x-ray reflectivity as a function of time and irradiance. Preliminary results are presented for a W/C multilayer. Work in progress to model the experiment is discussed. 13 refs., 4 figs.

  2. Stig Sundell at the bent crystal X-ray spectrometer for the X-ray shift experiment.

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The bent crystal X-ray spectrometer is being used to measure small shifts in the frequencies of X-rays emitted from the lower electron energy levels, in order to learn about the size of the nuclei concerned

  3. X-ray framing camera for pulsed, high current, electron beam x-ray sources

    CERN Document Server

    Failor, B H; Riordan, j c; Lojewski, D Y

    2007-01-01

    High power x-ray sources built for nuclear weapons effects testing are evolving toward larger overall diameters and smaller anode cathode gaps. We describe a framing camera developed to measure the time-evolution of these 20-50 ns pulsed x-ray sources produced by currents in the 1.5-2.5 MA range and endpoint voltages between 0.2 and 1.5 MV. The camera has up to 4 frames with 5 ns gate widths; the frames are separated by 5 ns. The image data are recorded electronically with a gated intensified CCD camera and the data are available immediately following a shot. A fast plastic scintillator (2.1 ns decay time) converts the x-rays to visible light and, for high sensitivity, a fiber optic imaging bundle carries the light to the CCD input. Examples of image data are shown.

  4. X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Bitter, Manfred L.; Fraekel, Benjamin; Gorman, James L.; Hill, Kenneth W.; Roquemore, Lane A.; Stodiek, Wolfgang; Goeler, Schweickhard von

    1999-05-01

    Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokamak fusion experiment to provide spatially and temporally resolved data on plasma parameters such as ion temperature, toroidal and poloidal rotation, electron temperature, impurity ion charge-state distributions, and impurity transport. The imaging properties of these spherically or toroidally curved crystals provide both spectrally and spatially resolved X-ray data from the plasma using only one small spherically or toroidally curved crystal, thus eliminating the requirement for a large array of crystal spectrometers and the need to cross-calibrate the various crystals.

  5. Observing Solvation Dynamics with Simultaneous Femtosecond X-ray Emission Spectroscopy and X-ray Scattering

    DEFF Research Database (Denmark)

    Haldrup, Kristoffer; Gawelda, Wojciech; Abela, Rafael

    2016-01-01

    In liquid phase chemistry dynamic solute solvent interactions often govern the path, ultimate outcome, and efficiency of chemical reactions. These steps involve many-body movements on subpicosecond time scales and thus ultrafast structural tools capable of capturing both intramolecular electronic......, confirming previous ab initio molecular dynamics simulations. Structural changes in the aqueous solvent associated with density and temperature changes occur with similar to 1 ps time constants, characteristic for structural dynamics in water. This slower time scale of the solvent response allows us...... rearrangement of the solute with X-ray emission spectroscopy, thus establishing time zero for the ensuing X-ray diffuse scattering analysis. The simultaneously recorded X-ray diffuse scattering atterns reveal slower subpicosecond dynamics triggered by the intramolecular structural dynamics of the photoexcited...

  6. X-ray Cryogenic Facility (XRCF) Handbook

    Science.gov (United States)

    Kegley, Jeffrey R.

    2016-01-01

    The X-ray & Cryogenic Facility (XRCF) Handbook is a guide for planning operations at the facility. A summary of the capabilities, policies, and procedures is provided to enhance project coordination between the facility user and XRCF personnel. This handbook includes basic information that will enable the XRCF to effectively plan and support test activities. In addition, this handbook describes the facilities and systems available at the XRCF for supporting test operations. 1.2 General Facility Description The XRCF was built in 1989 to meet the stringent requirements associated with calibration of X-ray optics, instruments, and telescopes and was subsequently modified in 1999 & 2005 to perform the challenging cryogenic verification of Ultraviolet, Optical, and Infrared mirrors. These unique and premier specialty capabilities, coupled with its ability to meet multiple generic thermal vacuum test requirements for large payloads, make the XRCF the most versatile and adaptable space environmental test facility in the Agency. XRCF is also recognized as the newest, most cost effective, most highly utilized facility in the portfolio and as one of only five NASA facilities having unique capabilities. The XRCF is capable of supporting and has supported missions during all phases from technology development to flight verification. Programs/projects that have benefited from XRCF include Chandra, Solar X-ray Imager, Hinode, and James Webb Space Telescope. All test programs have been completed on-schedule and within budget and have experienced no delays due to facility readiness or failures. XRCF is currently supporting Strategic Astrophysics Technology Development for Cosmic Origins. Throughout the years, XRCF has partnered with and continues to maintain positive working relationships with organizations such as ATK, Ball Aerospace, Northrop Grumman Aerospace, Excelis (formerly Kodak/ITT), Smithsonian Astrophysical Observatory, Goddard Space Flight Center, University of Alabama

  7. Early X-Ray Flares in GRBs

    Science.gov (United States)

    Ruffini, R.; Wang, Y.; Aimuratov, Y.; Barres de Almeida, U.; Becerra, L.; Bianco, C. L.; Chen, Y. C.; Karlica, M.; Kovacevic, M.; Li, L.; Melon Fuksman, J. D.; Moradi, R.; Muccino, M.; Penacchioni, A. V.; Pisani, G. B.; Primorac, D.; Rueda, J. A.; Shakeri, S.; Vereshchagin, G. V.; Xue, S.-S.

    2018-01-01

    We analyze the early X-ray flares in the GRB “flare–plateau–afterglow” (FPA) phase observed by Swift-XRT. The FPA occurs only in one of the seven GRB subclasses: the binary-driven hypernovae (BdHNe). This subclass consists of long GRBs with a carbon–oxygen core and a neutron star (NS) binary companion as progenitors. The hypercritical accretion of the supernova (SN) ejecta onto the NS can lead to the gravitational collapse of the NS into a black hole. Consequently, one can observe a GRB emission with isotropic energy {E}{iso}≳ {10}52 erg, as well as the associated GeV emission and the FPA phase. Previous work had shown that gamma-ray spikes in the prompt emission occur at ∼ {10}15{--}{10}17 cm with Lorentz Gamma factors {{Γ }}∼ {10}2{--}{10}3. Using a novel data analysis, we show that the time of occurrence, duration, luminosity, and total energy of the X-ray flares correlate with E iso. A crucial feature is the observation of thermal emission in the X-ray flares that we show occurs at radii ∼1012 cm with {{Γ }}≲ 4. These model-independent observations cannot be explained by the “fireball” model, which postulates synchrotron and inverse-Compton radiation from a single ultrarelativistic jetted emission extending from the prompt to the late afterglow and GeV emission phases. We show that in BdHNe a collision between the GRB and the SN ejecta occurs at ≃1010 cm, reaching transparency at ∼1012 cm with {{Γ }}≲ 4. The agreement between the thermal emission observations and these theoretically derived values validates our model and opens the possibility of testing each BdHN episode with the corresponding Lorentz Gamma factor.

  8. AXIS - Advanced X-ray Imaging Sarellite

    Science.gov (United States)

    Loewenstein, Michael; AXIS Team

    2018-01-01

    We present an overview of the Advanced X-ray Imaging Satellite (AXIS), a probe mission concept under study to the 2020 Decadal survey. AXIS follows in the footsteps of the spectacularly successful Chandra X-ray Observatory with similar or higher angular resolution and an order of magnitude more collecting area in the 0.3-10 keV band over a 15' field of view. These capabilities are designed to attain a wide range of science goals such as (i) measuring the event horizon scale structure in AGN accretion disks and the spin of supermassive black holes through monitoring of gravitationally microlensed quasars; (ii) understanding AGN and starburst feedback in galaxies and galaxy clusters through direct imaging of winds and interaction of jets and via spatially resolved imaging of galaxies at high-z; (iii) probing the fueling of AGN by resolving the SMBH sphere of influence in nearby galaxies; (iv) investigating hierarchical structure formation and the SMBH merger rate through measurement of the occurrence rate of dual AGN and occupation fraction of SMBHs; (v) advancing SNR physics and galaxy ecology through large detailed samples of SNR in nearby galaxies; (vi) measuring the Cosmic Web through its connection to cluster outskirts. With a nominal 2028 launch, AXIS benefits from natural synergies with LSST, ELTs, ALMA, WFIRST and ATHENA, and will be a valuable precursor to Lynx. AXIS utilizes breakthroughs in the construction of light-weight X-ray optics from mono-crystalline silicon blocks, and developments in the fabrication of large format, small pixel, high readout detectors.

  9. High Resolution X-ray Views of Solar System Objects

    Science.gov (United States)

    Branduardi-Raymont, Graziella

    2011-05-01

    Over the last decade Chandra, and XMM-Newton, have revealed the beauty and multiplicity of X-ray emissions in our solar system: high resolution data, in both spectral and spatial domains, have been crucial in disentangling the physical processes at work. The talk will review the main findings in this area at the boundary between astrophysics and planetary science, and will show how the solar system offers `next door’ examples of widespread astrophysical phenomena. Jupiter shows bright X-ray aurorae, arising from the interactions of local and/or solar wind ions, and electrons, with its powerful magnetic environment: the ions undergo charge exchange with atmospheric neutrals and generate soft X-ray line emission, and the electrons give rise to bremsstrahlung X-rays. Chandra's unparalleled spatial resolution has shown how the X-ray footprints of the electrons in the aurorae coincide with the bright FUV auroral oval, indicating that the same electron population is likely to be at the origin of both emissions. Moreover, Jupiter's disk scatters solar X-rays, displaying a spectrum that closely resembles that of solar flares. Saturn has not revealed X-ray aurorae (yet), but its disk X-ray brightness, like Jupiter's, is strictly correlated with the Sun's X-ray output. A bright X-ray spot has also been resolved by Chandra on the eastern ansa of Saturn's rings, and its spectrum suggests an origin in the fluorescent scattering of solar X-rays on the rings icy particles. Both Mars and Venus have X-ray emitting disks and exospheres, which can be clearly resolved at high spectral and spatial resolution. And the Earth has bright X-ray aurorae that have been targets of Chandra observations. Finally, comets, with their extended neutral comae and extremely line-rich X-ray spectra, are spectacular X-ray sources, and ideal probes of the conditions of the solar wind in the Sun's proximity.

  10. X-ray characterisation of nanostructured materials

    DEFF Research Database (Denmark)

    Oddershede, Jette

    ¯brous structure. The study was initiated based on the need for a reliable crystallinity determination from XRPD. It was shown that for future crystallinity determinations a new method based on Rietveld re¯nements should be preferred. If additional in- formation about particle shape, size or size distribution......X-ray powder di®raction (XRPD) is an excellent tool for characterising the bulk structure of crystalline materials. Along with the growing interest in exploiting materials with decreasing particle sizes and increasing number of defects, factors that complicate the traditional interpretation...... using a combination of Debye simulations and param- eterised Principal Component Analysis (PCA)....

  11. Next-Generation X-Ray Astronomy

    Science.gov (United States)

    White, Nicholas E.

    2011-01-01

    The future timing capabilities in X-ray astronomy will be reviewed. This will include reviewing the missions in implementation: Astro-H, GEMS, SRG, and ASTROSAT; those under study: currently ATHENA and LOFT; and new technologies that may enable future missions e.g. Lobster eye optics. These missions and technologies will bring exciting new capabilities across the entire time spectrum from micro-seconds to years that e.g. will allow us to probe close to the event horizon of black holes and constrain the equation of state of neutron stars.

  12. BXA: Bayesian X-ray Analysis

    Science.gov (United States)

    Buchner, Johannes

    2016-10-01

    BXA connects the nested sampling algorithm MultiNest (ascl:1109.006) to the X-ray spectral analysis environments Xspec/Sherpa for Bayesian parameter estimation and model comparison. It provides parameter estimation in arbitrary dimensions and plotting of spectral model vs. the data for best fit, posterior samples, or each component. BXA allows for model selection; it computes the evidence for the considered model, ready for use in computing Bayes factors and is not limited to nested models. It also visualizes deviations between model and data with Quantile-Quantile (QQ) plots, which do not require binning and are more comprehensive than residuals.

  13. Hard X-ray laue monochromator

    OpenAIRE

    Kocharian, Vagan Rashidovich; Gogolev, Aleksey Sergeevich; Kiziridi, A. A.; Batranin, Andrey Viktorovich; Muradyan, T. R.

    2016-01-01

    Experimental studies of X-ray diffraction from reflecting atomic planes (1011) of X-cut quartz single crystal in Laue geometry influenced by the temperature gradient were carried out. It is shown that by using the temperature gradient it is possible to reflect a hard Xray beam with photon energy near the 100 keV with high efficiency. It has been experimentally proved that the intensity of the reflected beam can be increased by more than order depending on the value of the temperature gradient.

  14. Ultraluminous supersoft X-ray sources

    Science.gov (United States)

    Liu, Jifeng; Bai, Yu; Wang, Song; Justham, Stephen; Lu, You-Jun; Gu, Wei-Min; Liu, Qing-Zhong; di Stefano, Rosanne; Guo, Jin-Cheng; Cabrera-Lavers, Antonio; Álvarez, Pedro; Cao, Yi; Kulkarni, Shri

    2017-06-01

    While ultraluminous supersoft X-ray sources (ULSs) bear features for intermediate mass black holes or very massive white dwarfs possibly close to Chandrasekhar mass limit, our recent discovery of processing relativistic baryonic jets from a prototype ULS in M81 demonstrate that they are not IMBHs or WDs, but black holes accreting at super-Eddington rates. This discovery strengthens the recent ideas that ULXs are stellar black holes with supercritical accretion, and provides a vivid manifestation of what happens when a black hole devours too much, that is, it will generate thick disk winds and fire out sub-relativistic baryonic jets along the funnel as predicted by recent numerical simulations.

  15. Coherent methods in X-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Gorobtsov, Oleg

    2017-05-15

    X-ray radiation has been used to study structural properties of materials for more than a hundred years. Construction of extremely coherent and bright X-ray radiation sources such as free electron lasers (FELs) and latest generationstorage rings led to rapid development of experimental methods relying on high radiation coherence. These methods allow to perform revolutionary studies in a wide range of fields from solid state physics to biology. In this thesis I focus on several important problems connected with the coherent methods. The first part considers applications of dynamical diffraction theory on crystals to studies with coherent X-ray radiation. It presents the design of a high-resolution spectrometer for free electron lasers that should allow to resolve spectral structure of individual FEL pulses. The spectrometer is based on the principle of dynamical diffraction focusing. The knowledge of individual FEL pulse spectra is necessary for understanding FEL longitudinal coherence. In the same part I present quasi-kinematical approximation to dynamical theory which allows to treat analytically phase effects observed in X-ray coherent imaging on nanocrystals. These effects may play a big role when methods such as ptychography are used to study crystalline samples. The second part deals with measurements of FEL coherence properties using intensity - intensity interferometry. Results of several experiments performed at FELs FLASH and LCLS are revealed in this section. I have developed models and theories to explain the behavior observed in experiments on FLASH. These models allowed to extract information about external positional jitter of FEL pulses and secondary beams present in FEL radiation. In the LCLS experiment the Hanbury Brown and Twiss type interferometry was performed on Bragg peaks from colloidal crystal. This did not require additional measurements without the sample and information was extracted directly from diffraction patterns. Therefore intensity

  16. Elements of modern X-ray physics

    CERN Document Server

    Als-Nielsen, Jens

    2011-01-01

    Eagerly awaited, this second edition of a best-selling text comprehensively describes from a modern perspective the basics of x-ray physics as well as the completely new opportunities offered by synchrotron radiation. Written by internationally acclaimed authors, the style of the book is to develop the basic physical principles without obscuring them with excessive mathematics. The second edition differs substantially from the first edition, with over 30% new material, including: A new chapter on non-crystalline diffraction - designed to appeal to the large community wh

  17. X-ray morphology after vagotomy

    Energy Technology Data Exchange (ETDEWEB)

    Beeger, R.; Vogel, H.

    1983-12-01

    Vagotomy is often followed by changes in the shape and motoric function of the stomach which usually return to normal in the course of a few months. The morphological changes which are typical for the different surgical techniques are described on the basis of references and the authors' own findings. X-ray examination contributes towards distinguishing regular postoperative changes from complications. The necessary long-term follow-ups to discover any possible recurrence of ulcers should be supplemented by gastroscopy.

  18. Glancing angle synchrotron X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Cernik, R.J. [Daresbury Lab., Warrington, WA (United States)

    1996-09-01

    This paper describes in basic detail some of the techniques that can be used to study thin films and surfaces. These are all in the X-ray region and cover reflectivity, diffraction form polycrystalline films, textured films and single crystal films. Other effects such as fluorescence and diffuse scattering are mentioned but not discussed in detail. Two examples of the reflectivity from multilayers and the diffraction from iron oxide films are discussed. The advantages of the synchrotron for these studies is stressed and the experimental geometries that can be employed are described i detail. A brief bibliography is provided at the end to accompany this part of the 1996 Frascati school.

  19. Bone age assessment by dual-energy X-ray absorptiometry in children: An alternative for X-ray?

    NARCIS (Netherlands)

    D.H.M. Heppe (Denise); H.R. Taal (Rob); G.D.S. Ernst (Gesina); E.L.T. van den Akker (Erica); M.H. Lequin (Maarten); A.C.S. Hokken-Koelega (Anita); J.J.M. Geelhoed (Miranda); V.W.V. Jaddoe (Vincent)

    2012-01-01

    textabstractObjective: The aim of the study was to validate dual-energy X-ray absorptiometry (DXA) as a method to assess bone age in children. Methods: Paired dual-energy X-ray absorptiometry (DXA) scans and X-rays of the left hand were performed in 95 children who attended the paediatric

  20. The color of X-rays: Spectral X-ray computed tomography using energy sensitive pixel detectors

    NARCIS (Netherlands)

    Schioppa, E.J.

    2014-01-01

    Energy sensitive X-ray imaging detectors are produced by connecting a semiconductor sensor to a spectroscopic pixel readout chip. In this thesis, the applicability of such detectors to X-ray Computed Tomography (CT) is studied. A prototype Medipix based silicon detector is calibrated using X-ray

  1. Characterizing X-Ray and Radio Emission in the Black Hole X-Ray Binary V404 Cygni During Quiescence

    DEFF Research Database (Denmark)

    Rana, Vikram; Loh, Alan; Corbel, Stephane

    2016-01-01

    We present results from multi-wavelength simultaneous X-ray and radio observations of the black hole X-ray binary V404 Cyg in quiescence. Our coverage with NuSTAR provides the very first opportunity to study the X-ray spectrum of V404 Cyg at energies above 10 keV. The unabsorbed broadband (0...

  2. X-Ray and Near-Infrared Spectroscopy of Dim X-Ray Point Sources Constituting the Galactic Ridge X-Ray Emission

    Directory of Open Access Journals (Sweden)

    Kumiko Morihana

    2014-12-01

    Full Text Available We present the results of X-ray and Near-Infrared observations of the Galactic Ridge X-ray Emission (GRXE. We extracted 2,002 X-ray point sources in the Chandra Bulge Field (l =0°.113, b = 1°.424 down to ~10-14.8 ergscm-2s-1 in 2-8 keV band with the longest observation (900 ks of the GRXE. Based on X-ray brightness and hardness, we classied the X-ray point sources into three groups: A (hard, B (soft and broad spectrum, and C (soft and peaked spectrum. In order to know populations of the X-ray point sources, we carried out NIR imaging and spectroscopy observation. We identied 11% of X-ray point sources with NIR and extracted NIR spectra for some of them. Based on X-ray and NIR properties, we concluded that non-thermal sources in the group A are mostly active galactic nuclei and the thermal sources are mostly white dwarf binaries such as cataclysmic variables (CVs and Pre-CVs. We concluded that the group B and C sources are X-ray active stars in flare and quiescence, respectively.

  3. Development of X-Ray Optics for the International X-Ray Observatory (IXO)

    Science.gov (United States)

    Zhang, William W.; Bolognese, J.; Byron, G.; Caldwell, D.; Chan, K.; Content, D. A.; Gubarev, M.; Davis, W.; Freeman, M.; Hadjimichael, T. J.; hide

    2009-01-01

    The International X-ray Observatory requires mirror assemblies with unprecedented characteristics that cannot be provided by existing optical technologies. In the past several years, the project has supported a vigorous mirror technology development program. This program includes the fabrication of lightweight mirror segments by slumping commercially available thin glass sheets, the support and mounting of these thin mirror segments for accurate metrology, the mounting and attachment of these mirror segments for the purpose of X-ray tests, and development of methods for aligning and integrating these mirror segments into mirror assemblies. This paper describes our efforts and developments in these areas.

  4. Proceedings of the workshop on X-ray computed microtomography

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    This report consists of vugraphs from the nine presentations at the conference. Titles of the presentations are: CMT: Applications and Techniques; Computer Microtomography Using X-rays from Third Generation Synchrotron X-ray; Approaches to Soft-X-ray Nanotomography; Diffraction Enhanced Tomography; X-ray Computed Microtomography Applications at the NSLS; XCMT Applications in Forestry and Forest Products; 3DMA: Investigating Three Dimensional Pore Geometry from High Resolution Images; X-ray Computed Microtomography Studies of Volcanic Rock; and 3-D Visualization of Tomographic Volumes.

  5. Soft X-Ray Emissions from Planets and Moons

    Science.gov (United States)

    Bhardwaj, A.; Gladstone, G. R.; Elsner, R. F.; Waite, J. H., Jr.; Grodent, D.; Lewis, W. S.; Crary, F. J.; Weisskopf, M. C.; Howell, R. R.; Johnson, R. E.; hide

    2002-01-01

    The soft x-ray energy band (less than 4 keV) is an important spectral regime for planetary remote sensing, as a wide variety of solar system objects are now known to shine at these wavelengths. These include Earth, Jupiter, comets, moons, Venus, and the Sun. Earth and Jupiter, as magnetic planets, are observed to emanate strong x-ray emissions from their auroral (polar) regions, thus providing vital information on the nature of precipitating particles and their energization processes in planetary magnetospheres. X rays from low latitudes have also been observed on these planets, resulting largely from atmospheric scattering and fluorescence of solar x-rays. Cometary x-rays are now a well established phenomena, more than a dozen comets have been observed at soft x-ray energies, with the accepted production mechanism being charge-exchange between heavy solar wind ions and cometary neutrals. Also, Lunar x-rays have been observed and are thought to be produced by scattering and fluorescence of solar x-rays from the Moon's surface. With the advent of sophisticated x-ray observatories, e.g., Chandra and XMM-Newton, the field of planetary x-ray astronomy is advancing at a much faster pace. The Chandra X-ray Observatory (CXO) has recently captured soft x-rays from Venus. Venusian x-rays are most likely produced through fluorescence of solar x-rays by C and O atoms in the upper atmosphere. Very recently, using CXO we have discovered soft x-rays from the moons of Jupiter-Io, Europa, and probably Ganymede. The plausible source of the x-rays from the Galilean satellites is bombardment of their surfaces by energetic (greater than 10 KeV) ions from the inner magnetosphere of Jupiter. The Io plasma Torus (IPT) is also discovered by CXO to be a source of soft x-rays by CXO have revealed a mysterious pulsating (period approx. 45 minutes) x-ray hot spot is fixed in magnetic latitude and longitude and is magnetically connected to a region in the outer magnetosphere of Jupiter. These

  6. Fundamentals of energy dispersive X-ray analysis

    CERN Document Server

    Russ, John C; Kiessling, R; Charles, J

    1984-01-01

    Fundamentals of Energy Dispersive X-ray Analysis provides an introduction to the fundamental principles of dispersive X-ray analysis. It presents descriptions, equations, and graphs to enable the users of these techniques to develop an intuitive and conceptual image of the physical processes involved in the generation and detection of X-rays. The book begins with a discussion of X-ray detection and measurement, which is accomplished by one of two types of X-ray spectrometer: energy dispersive or wavelength dispersive. The emphasis is on energy dispersive spectrometers, given their rather wid

  7. XMM-Newton X-Ray Observation of Jupiter

    Science.gov (United States)

    Waite, J. Hunter

    2005-01-01

    Soft X-ray emission has been observed from the disk of both Jupiter and Saturn as well as from the auroral regions of these planets. The low-latitude disk emission as observed by ROSAT, the Chandra X-Ray Observatory, and XMM-Newton appears to be uniformly distributed across the disk and to be correlated with solar activity. These characteristics suggest that the disk x-rays are produced by: (1) the elastic scattering of solar X-rays by atmospheric neutrals and (2) the absorption of solar X-rays in the carbon K-shell followed by fluorescent emission. The carbon atoms are found in methane molecules located below the homopause. In this paper we present the results of calculations of the scattering albedo for soft x-rays. We also show the calculated x-ray intensity for a range of atmospheric abundances for Jupiter and Saturn and for a number of solar irradiance spectra. The model calculations are compared with recent x-ray observations of Jupiter and Saturn. We conclude that the emission of soft x-rays from the disks of Jupiter and Saturn can be largely explained by the scattering and fluorescence of soft x-rays. We suggest that measured x-ray intensities from the disk regions of Jupiter

  8. Test facility for astronomical x-ray optics

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Lewis, Robert A.; Bordas, J.

    1990-01-01

    Grazing incidence x-ray optics for x-ray astronomical applications are used outside the earth's atmosphere. These devices require a large collection aperture and the imaging of an x-ray source that is essentially placed at infinity. The ideal testing system for these optical elements has...... to approximate that encountered under working conditions; however, the testing of these optical elements is notoriously difficult with conventional x-ray generators. Synchrotron radiation (SR) sources are sufficiently brilliant to produce a nearly perfect parallel beam over a large area while still retaining...... a flux considerably higher than that available from conventional x-ray generators. A facility designed for the testing of x-ray optics, particularly in connection with x-ray telescopes, is described. It is proposed that this facility will be accommodated at the Synchrotron Radiation Source...

  9. A Test Facility For Astronomical X-Ray Optics

    DEFF Research Database (Denmark)

    Lewis, R. A.; Bordas, J.; Christensen, Finn Erland

    1989-01-01

    Grazing incidence x-ray optics for x-ray astronomical applications are used outside the earths atmosphere. These devices require a large collection aperture and the imaging of an x-ray source which is essentially placed at infinity. The ideal testing system for these optical elements has...... to approximate that encountered under working conditions, however the testing of these optical elements is notoriously difficult with conventional x-ray generators. Synchrotron Radiation (SR) sources are sufficiently brilliant to produce a nearly perfect parallel beam over a large area whilst still retaining...... a flux considerably higher than that available from conventional x-ray generators. A facility designed for the testing of x-ray optics, particularly in connection with x-ray telescopes is described below. It is proposed that this facility will be accommodated at the Synchrotron Radiation Source...

  10. Characterization of a triboelectric x-ray spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Moya-Sanchez, E. Ulises; Romo-Espejel, J. A.; Aceves-Aldrete, F. J. [Departamento de Fisica, CUCEI, Universidad de Guadalajara (Mexico)

    2012-10-23

    Low-energy X-ray imaging system has been useful in medical diagnostic in order to obtain high contrast in soft tissue. Recently, Camara et al. and most recently Hird et al. have produced low-energy X-rays using a triboelectric effect. The main aim of this work is to characterize the penetration (beam quality) of a triboelectric X-ray source in terms of the computed Half Value Layer (HVL). Additionally, the computed HVL of the triboelectric X-ray source has been compared with the HVL of X-ray tube Mo-anode (Apogee 5000). According to our computations the triboelectric X-ray source has a similar penetration such as a X-ray tube source.

  11. Technology development for soft X-ray spectroscopy

    Science.gov (United States)

    Törmä, P. T.; Sipilä, H. J.; Koskinen, T.; Mattila, M.

    2016-05-01

    X-ray spectroscopy instruments lose part of their performance due to the lack of suitable components for soft X-ray region below 1 keV. Therefore, in the analysis of low atomic number elements including lithium, beryllium, boron and carbon instrument sensitivity is often limited. In this work we describe how the performance of the spectroscopy of soft X-rays is significantly improved when all devices integrated in the spectroscopic instrument are suitable for both soft and hard X-rays. This concept is based on utilizing ultra-thin SiN X-ray windows with proven performance not only as a detector window but also as an X-ray source window. By including a soft-X-ray-sensitive silicon drift detector with efficient surface charge collection in this concept the sensitivity and performance of the instrument is significantly increased.

  12. X-Ray Optics: Past, Present, and Future

    Science.gov (United States)

    Zhang, William W.

    2010-01-01

    X-ray astronomy started with a small collimated proportional counter atop a rocket in the early 1960s. It was immediately recognized that focusing X-ray optics would drastically improve both source location accuracy and source detection sensitivity. In the past 5 decades, X-ray astronomy has made significant strides in achieving better angular resolution, large photon collection area, and better spectral and timing resolutions, culminating in the three currently operating X-ray observatories: Chandra, XMM/Newton, and Suzaku. In this talk I will give a brief history of X-ray optics, concentrating on the characteristics of the optics of these three observatories. Then I will discuss current X-ray mirror technologies being developed in several institutions. I will end with a discussion of the optics for the International X-ray Observatory that I have been developing at Goddard Space Flight Center.

  13. X-ray polarimetry an upcoming 'new' tool in Astronomy

    Science.gov (United States)

    Soffitta, P.

    2017-10-01

    Sensitive X-ray polarimetry promises to solve many different issues in X-ray Astronomy: from disentangling physics from geometry removing degeneracies in models of magnetars and X-ray binaries hosting neutron stars, to mapping ordered magnetic fields in Supernova Remnants and Pulsar Wind Nebulae. It constrains emission mechanisms in blazars and solves the mistery of X-ray emission from cold molecular clouds in the galactic center. Moreover it can answer to questions of fundamental physics. XIPE the X-ray Imaging Polarimetry Explorer accomplished phase A as an ESA M4 candidate and IXPE the Imaging X-ray Polarimetry explorer was selected as next SMEX mission by NASA for a flight in late 2020. In this talk I will describe both missions and their ability to make energy, time and angle resolved polarimetry thanks to a detector developed at this aim and to X-ray optics with a large effective area.

  14. X-ray diffraction imaging of material microstructures

    KAUST Repository

    Varga, Laszlo

    2016-10-20

    Various examples are provided for x-ray imaging of the microstructure of materials. In one example, a system for non-destructive material testing includes an x-ray source configured to generate a beam spot on a test item; a grid detector configured to receive x- rays diffracted from the test object; and a computing device configured to determine a microstructure image based at least in part upon a diffraction pattern of the x-rays diffracted from the test object. In another example, a method for determining a microstructure of a material includes illuminating a beam spot on the material with a beam of incident x-rays; detecting, with a grid detector, x-rays diffracted from the material; and determining, by a computing device, a microstructure image based at least in part upon a diffraction pattern of the x-rays diffracted from the material.

  15. Observation and theory of X-ray mirages.

    Science.gov (United States)

    Magnitskiy, Sergey; Nagorskiy, Nikolay; Faenov, Anatoly; Pikuz, Tatiana; Tanaka, Mamoko; Ishino, Masahiko; Nishikino, Masaharu; Fukuda, Yuji; Kando, Masaki; Kawachi, Tetsuya; Kato, Yoshiaki

    2013-01-01

    The advent of X-ray lasers allowed the realization of compact coherent soft X-ray sources, thus opening the way to a wide range of applications. Here we report the observation of unexpected concentric rings in the far-field beam profile at the output of a two-stage plasma-based X-ray laser, which can be considered as the first manifestation of a mirage phenomenon in X-rays. We have developed a method of solving the Maxwell-Bloch equations for this problem, and find that the experimentally observed phenomenon is due to the emergence of X-ray mirages in the plasma amplifier, appearing as phase-matched coherent virtual point sources. The obtained results bring a new insight into the physical nature of amplification of X-ray radiation in laser-induced plasma amplifiers and open additional opportunities for X-ray plasma diagnostics and extreme ultraviolet lithography.

  16. Food Irradiation Using Electron Beams and X-Rays

    Science.gov (United States)

    Miller, Bruce

    2003-04-01

    mass throughput (dM/dt in kg/s) of an accelerator-based system is proportional to the average beam power (P in kW), and inversely proportional to the minimum required dose (Dm in kGy, with 1 kGy = 1 kJ/kg). The constant of proportionality is the mass throughput efficiency. Throughput efficiencies of 0.4 or better are typical of electron beam installations, but are only 0.025-0.035 for x-ray installations, primarily because of the inefficiency of bremsstrahlung generation at 5 MeV (about 8an axially-coupled, standing-wave, L-band linac with an average power in excess of 100 kW to achieve reasonable throughput rates with x-ray processing. Various design aspects of this new machine will be presented.

  17. Enhanced dynamic range x-ray imaging.

    Science.gov (United States)

    Haidekker, Mark A; Morrison, Logan Dain-Kelley; Sharma, Ajay; Burke, Emily

    2017-03-01

    X-ray images can suffer from excess contrast. Often, image exposure is chosen to visually optimize the region of interest, but at the expense of over- and underexposed regions elsewhere in the image. When image values are interpreted quantitatively as projected absorption, both over- and underexposure leads to the loss of quantitative information. We propose to combine multiple exposures into a composite that uses only pixels from those exposures in which they are neither under- nor overexposed. The composite image is created in analogy to visible-light high dynamic range photography. We present the mathematical framework for the recovery of absorbance from such composite images and demonstrate the method with biological and non-biological samples. We also show with an aluminum step-wedge that accurate recovery of step thickness from the absorbance values is possible, thereby highlighting the quantitative nature of the presented method. Due to the higher amount of detail encoded in an enhanced dynamic range x-ray image, we expect that the number of retaken images can be reduced, and patient exposure overall reduced. We also envision that the method can improve dual energy absorptiometry and even computed tomography by reducing the number of low-exposure ("photon-starved") projections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Microwave calorimetry using X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Nicula, R., E-mail: radu.nicula@empa.ch [Empa, Swiss Federal Laboratories for Materials Science and Technology, Advanced Materials Processing, Feuerwerkerstr. 39, CH-3602 Thun (Switzerland); Stir, M. [Empa, Swiss Federal Laboratories for Materials Science and Technology, Advanced Materials Processing, Feuerwerkerstr. 39, CH-3602 Thun (Switzerland); Wurm, A. [University of Rostock, Institute of Physics, Wismarsche Str. 43-45, 18051 Rostock (Germany); Catala-Civera, J.M. [Universidad Politecnica de Valencia, Camino Vera s/n, E-46022 Valencia (Spain); Ishizaki, K.; Vaucher, S. [Empa, Swiss Federal Laboratories for Materials Science and Technology, Advanced Materials Processing, Feuerwerkerstr. 39, CH-3602 Thun (Switzerland); Zhuravlev, E.; Schick, C. [University of Rostock, Institute of Physics, Wismarsche Str. 43-45, 18051 Rostock (Germany)

    2011-11-10

    Highlights: Black-Right-Pointing-Pointer New approach for microwave calorimetry using synchrotron radiation powder diffraction. Black-Right-Pointing-Pointer In situ monitoring of the magnetostructural transformation of Co under magnetic microwave heating at 2.45 GHz. Black-Right-Pointing-Pointer Magnetic heat capacity of Co due to the spin-reorientation transition at microwave frequencies. - Abstract: An alternative approach for microwave calorimetry is proposed which relies on the synchrotron radiation powder diffraction technique as well as on the Grueneisen formalism for the analysis of thermal expansion. Cobalt was selected as suitable magnetic material for the present evaluation of the method. First results are reported concerning the calorimetric assessment of the HCP (hexagonal close-packed) to FCC (face centered cubic) transition of cobalt from in situ time-resolved X-ray diffraction experiments performed during magnetic (H-field) microwave heating. The X-ray calorimetry method yields specific heat capacity estimations that compare well with results from conventional differential scanning calorimetry measurements. In the presence of the 2.45 GHz microwave H-field, an 'anomalous' behaviour of the heat capacity across the structural phase transition is detected, which can be correlated with the magnetic spin reorientation transition of cobalt in the same temperature range.

  19. Multilayer X-ray optics at CHESS.

    Science.gov (United States)

    Kazimirov, Alexander; Smilgies, Detlef M; Shen, Qun; Xiao, Xianghui; Hao, Quan; Fontes, Ernest; Bilderback, Donald H; Gruner, Sol M; Platonov, Yuriy; Martynov, Vladimir V

    2006-03-01

    Almost half of the X-ray beamlines at the Cornell High Energy Synchrotron Source (CHESS) are based on multilayer optics. ;Traditional' multilayers with an energy resolution of DeltaE/E approximately 2% are routinely used to deliver X-ray flux enhanced by a factor of 10(2) in comparison with standard Si(111) optics. Sagittal-focusing multilayers with fixed radius provide an additional factor of 10 gain in flux density. High-resolution multilayer optics with DeltaE/E approximately 0.2% are now routinely used by MacCHESS crystallographers. New wide-bandpass multilayers with DeltaE/E = 5% and 10% have been designed and tested for potential applications in macromolecular crystallography. Small d-spacing multilayers with d < or = 20 A have been successfully used to extend the energy range of multilayer optics. Analysis of the main characteristics of the Mo/B4C and W/B4C small d-spacing multilayer optics shows enhancement in their performance at higher energies. Chemical vapour deposited SiC, with a bulk thermal conductivity of a factor of two higher than that of silicon, has been successfully introduced as a substrate material for multilayer optics. Characteristics of different types of multilayer optics at CHESS beamlines and their applications in a variety of scattering, diffraction and imaging techniques are discussed.

  20. SphinX x-ray spectrophotometer

    Science.gov (United States)

    Kowaliński, Mirosław

    2012-05-01

    This paper presents assumptions to a PhD thesis. The thesis will be based on the construction of Solar Photometer in X-rays (SphinX). SphinX was an instrument developed to detect the soft X-rays from the Sun. It was flown on board the Russian CORONAS-Photon satellite from January 30, 2009 to the end of November, 2009. During 9 months in orbit SphinX provided an excellent and unique set of observations. It revealed about 750 flares and brightenings. The instrument observed in energy range 1.0 - 15.0 keV with resolution below ~0.5 keV. Here, the SphinX instrument objectives, design, performance and operation principle are described. Below results of mechanical and thermal - vacuum tests necessary to qualify the instrument to use in space environment are presented. Also the calibration results of the instrument are discussed. In particular detail it is described the Electrical Ground Support Equipment (EGSE) for SphinX. The EGSE was used for all tests of the instrument. At the end of the paper results obtained from the instrument during operation in orbit are discussed. These results are compared with the other similar measurements performed from the separate spacecraft instruments. It is suggested design changes in future versions of SphinX.

  1. Hard X-ray Footpoint Source Sizes

    Science.gov (United States)

    Dennis, Brian R.; Kontar, E. P.; Gopie, A. A.; Tolbert, A. K.; Schwartz, R. A.

    2010-05-01

    RHESSI has detected compact hard (25 - 100 keV) X-ray sources that are ɜ arcseconds (FWHM) in extent for certain flares (Dennis and Pernak (2009). These sources are believed to be at magnetic loop footpoints that are known from observations at other wavelengths to be very small. Flare ribbons seen in the UV with TRACE, for example, are 1 arcsecond in width, and white light flares show structure at the 1 arcsecond level. However, Kontar and Jeffrey (2010) have shown that the measured extent should be >6 arcseconds, even if the X-ray emitting thick-target source is point-like. This is because of the strong albedo contribution in the measured energy range for a source located at the expected altitude of 1 Mm near the top of the chromosphere. This discrepancy between observations and model predictions may indicate that the source altitude is significantly lower than assumed or that the RHESSI image reconstruction procedures are not sensitive to the more diffuse albedo patch in the presence of a strong compact source. Results will be presented exploring the latter possibility using the Pixon image reconstruction procedure and other methods based on visibilities. Dennis, B. R. and Pernak, R. L., 2009, ApJ, 698, 2131-2143. Kontar, E. P. and Jeffrey, N. L. S., 2010, A&A, in press.

  2. Hard X-Ray Footprint Source Sized

    Science.gov (United States)

    Dennis, Brian R.; Kontar, E. P.

    2010-01-01

    RHESSI has detected compact hard (25 - 100 keV) X-ray sources that are Pernak (2009). These sources are believed to be at magnetic loop footpoints that are known from observations at other wavelengths to be very small. Flare ribbons seen in the W with TRACE, for example, are approx. 1 arcsecond in width, and white light flares show structure at the approx. 1 arcsecond level. However, Kontar and Jeffrey (2010) have shown that the measured extent should be >6 arcseconds, even if the X-ray emitting thick-target source is point-like. This is because of the strong albedo contribution in the measured energy range for a source located at the expected altitude of 1 Mm near the top of the chromosphere. This discrepancy between observations and model predictions may indicate that the source altitude is significantly lower than assumed or that the RHESSI image reconstruction procedures are not sensitive to the more diffuse albedo patch in the presence of a strong compact source. Results will be presented exploring the latter possibility using the Pixon image reconstruction procedure and other methods based on visibilities.

  3. X-ray tomography on TCV

    Energy Technology Data Exchange (ETDEWEB)

    Anton, M.; Weisen, H.; Dutch, M.J.; Buhlmann, F.; Chavan, R.; Marletaz, B.; Marmillod, P.; Paris, P. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1996-04-01

    The TCV Tokamak offers an outstanding variability of the plasma shape. Using X-ray tomography, the shape of the inner flux surfaces of a poloidal cross section of the plasma can be reconstructed, including fast variations due to MHD activity. The hardware as well as the software of the 200 channel system developed for TCV is described. A new, `dynamical` calibration is used. The actual plasma temperature and some global profile parameters serve to determine the spectrum-dependent efficiency of the photodiodes. Compared to a `static` calibration with constant calibration factors, an enhanced quality of the reconstructed images is observed. The tomographic inversion is performed using a variety of methods such as Maximum Entropy, linear Regularisation and a new method making use of the Fisher information of the emissivity distribution. The merits of the different algorithms which have been implemented as MATLAB functions are compared. The tomographic inversion results are analysed with the help of the biorthogonal decomposition, allowing e.g. identification of MHD modes without using any a priori information on the poloidal mode structure. Recent results on the dependence of sawtooth activity on the plasma triangularity are presented to demonstrate the performance of the soft X-ray tomography system. (author) 14 figs., 2 tabs., 26 refs.

  4. Thermoluminescent response of CaSO{sub 4}:Dy+PTFE induced by X-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, L. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694 C.P. 11500 Mexico D.F. (Mexico); Rivera, T., E-mail: trivera@ipn.mx [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694 C.P. 11500 Mexico D.F. (Mexico); Jimenez, Y.; Alvarez, R.; Zeferino, J.; Vazquez, A. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-Legaria, IPN. Av. Legaria 694 C.P. 11500 Mexico D.F. (Mexico); Azorin, J. [Universidad Autonoma Metropolitana-Iztapalapa. Av. San Rafael Atlixco 186, C.P. 09340 Mexico D.F. (Mexico)

    2012-07-15

    The aim of the present work was to evaluate the feasibility of the utilization of CaSO{sub 4}:Dy pellets for X-ray measurements in a general radiology department. Thermoluminescence (TL) response of CaSO{sub 4}:Dy+PTFE was compared to the TL response of commercial LiF:Mg,Ti (TLD-100) samples. TL pellets were exposed to X-ray beam from X-ray machine CMR for clinical diagnosis purpose. The calibration curve of CaSO{sub 4}:Dy+PTFE was obtained and it showed a linear response as a function of absorbed dose in air at the studied dose interval. Despite this fact, this material can be used for X-ray beams measurements if appropriate calibration procedures are performed. - Highlights: Black-Right-Pointing-Pointer Developing of CaSO{sub 4}:Dy to quasimono-energetic X-ray low energy dosimetry. Black-Right-Pointing-Pointer Thermoluminescent response of caSO{sub 4}:Dy to X-ray low dose. Black-Right-Pointing-Pointer TL characteristics of CaSO{sub 4}:Dy for X-ray beam quality control.

  5. Femtosecond X-ray magnetic circular dichroism absorption spectroscopy at an X-ray free electron laser

    Science.gov (United States)

    Higley, Daniel J.; Hirsch, Konstantin; Dakovski, Georgi L.; Jal, Emmanuelle; Yuan, Edwin; Liu, Tianmin; Lutman, Alberto A.; MacArthur, James P.; Arenholz, Elke; Chen, Zhao; Coslovich, Giacomo; Denes, Peter; Granitzka, Patrick W.; Hart, Philip; Hoffmann, Matthias C.; Joseph, John; Le Guyader, Loïc; Mitra, Ankush; Moeller, Stefan; Ohldag, Hendrik; Seaberg, Matthew; Shafer, Padraic; Stöhr, Joachim; Tsukamoto, Arata; Nuhn, Heinz-Dieter; Reid, Alex H.; Dürr, Hermann A.; Schlotter, William F.

    2016-03-01

    X-ray magnetic circular dichroism spectroscopy using an X-ray free electron laser is demonstrated with spectra over the Fe L3,2-edges. The high brightness of the X-ray free electron laser combined with high accuracy detection of incident and transmitted X-rays enables ultrafast X-ray magnetic circular dichroism studies of unprecedented sensitivity. This new capability is applied to a study of all-optical magnetic switching dynamics of Fe and Gd magnetic sublattices in a GdFeCo thin film above its magnetization compensation temperature.

  6. Femtosecond X-ray magnetic circular dichroism absorption spectroscopy at an X-ray free electron laser.

    Science.gov (United States)

    Higley, Daniel J; Hirsch, Konstantin; Dakovski, Georgi L; Jal, Emmanuelle; Yuan, Edwin; Liu, Tianmin; Lutman, Alberto A; MacArthur, James P; Arenholz, Elke; Chen, Zhao; Coslovich, Giacomo; Denes, Peter; Granitzka, Patrick W; Hart, Philip; Hoffmann, Matthias C; Joseph, John; Le Guyader, Loïc; Mitra, Ankush; Moeller, Stefan; Ohldag, Hendrik; Seaberg, Matthew; Shafer, Padraic; Stöhr, Joachim; Tsukamoto, Arata; Nuhn, Heinz-Dieter; Reid, Alex H; Dürr, Hermann A; Schlotter, William F

    2016-03-01

    X-ray magnetic circular dichroism spectroscopy using an X-ray free electron laser is demonstrated with spectra over the Fe L(3,2)-edges. The high brightness of the X-ray free electron laser combined with high accuracy detection of incident and transmitted X-rays enables ultrafast X-ray magnetic circular dichroism studies of unprecedented sensitivity. This new capability is applied to a study of all-optical magnetic switching dynamics of Fe and Gd magnetic sublattices in a GdFeCo thin film above its magnetization compensation temperature.

  7. Femtosecond X-ray magnetic circular dichroism absorption spectroscopy at an X-ray free electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Higley, Daniel J., E-mail: dhigley@stanford.edu; Yuan, Edwin [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Hirsch, Konstantin; Dakovski, Georgi L.; Jal, Emmanuelle; Lutman, Alberto A.; Coslovich, Giacomo; Hart, Philip; Hoffmann, Matthias C.; Mitra, Ankush; Moeller, Stefan; Ohldag, Hendrik; Seaberg, Matthew; Stöhr, Joachim; Nuhn, Heinz-Dieter; Reid, Alex H.; Dürr, Hermann A.; Schlotter, William F. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Liu, Tianmin; MacArthur, James P. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Physics, Stanford University, Stanford, California 94305 (United States); and others

    2016-03-15

    X-ray magnetic circular dichroism spectroscopy using an X-ray free electron laser is demonstrated with spectra over the Fe L{sub 3,2}-edges. The high brightness of the X-ray free electron laser combined with high accuracy detection of incident and transmitted X-rays enables ultrafast X-ray magnetic circular dichroism studies of unprecedented sensitivity. This new capability is applied to a study of all-optical magnetic switching dynamics of Fe and Gd magnetic sublattices in a GdFeCo thin film above its magnetization compensation temperature.

  8. X-ray reflection in oxygen-rich accretion discs of ultracompact X-ray binaries

    DEFF Research Database (Denmark)

    Madej, O. K.; Garcia, Jeronimo; Jonker, P. G.

    2014-01-01

    . The donor star in these sources is a carbon-oxygen or oxygen-neon-magnesium white dwarf. Hence, the accretion disc is enriched with oxygen which makes the O viii Ly alpha line particularly strong. Modelling the X-ray reflection off a carbon- and oxygen-enriched, hydrogen- and helium-poor disc with models...

  9. Parabolic refractive X-ray lenses: a breakthrough in X-ray optics

    CERN Document Server

    Lengeler, B; Benner, B; Guenzler, T F; Kuhlmann, M; Tümmler, J; Simionovici, A S; Drakopoulos, M; Snigirev, A; Snigireva, I

    2001-01-01

    Refractive X-ray lenses, considered for a long time as unfeasible, have been realized with a rotational parabolic profile at our institute: The main features of the new lenses are: they focus in two directions and are free of spherical aberration. By varying the number of individual lenses in the stack the focal length can be chosen in a typical range from 0.5 to 2 m for photon energies between about 6 and 60 keV. The aperture of the lens is about 1 mm matching the angular divergence of undulator beams at 3d generation synchrotron radiation sources. They cope without problems with the heat load from the white beam of an undulator. Finally, they are easy to align and to operate. Refractive X-ray lenses can be used with hard X-rays in the same way as glass lenses can be used for visible light, if it is take into account that the numerical aperture is small (of the order 10 sup - sup 4). Being high-quality optical elements, the refractive X-ray lenses can be used for generating a focal spot in the mu m range wit...

  10. Enhancement of coherent X-ray diffraction from nanocrystals by introduction of X-ray optics.

    Science.gov (United States)

    Robinson, Ian; Pfeiffer, Franz; Vartanyants, Ivan; Sun, Yugang; Xia, Younan

    2003-09-22

    Coherent X-ray Diffraction is applied to investigate the structure of individual nanocrystalline silver particles in the 100nm size range. In order to enhance the available signal, Kirkpatrick-Baez focusing optics have been introduced in the 34-ID-C beamline at APS. Concerns about the preservation of coherence under these circumstances are addressed through experiment and by calculations.

  11. Optical and X-ray luminosities of expanding nebulae around ultraluminous X-ray sources

    Science.gov (United States)

    Siwek, Magdalena; Sądowski, Aleksander; Narayan, Ramesh; Roberts, Timothy P.; Soria, Roberto

    2017-09-01

    We have performed a set of simulations of expanding, spherically symmetric nebulae inflated by winds from accreting black holes in ultraluminous X-ray sources (ULXs). We implemented a realistic cooling function to account for free-free and bound-free cooling. For all model parameters we considered, the forward shock in the interstellar medium becomes radiative at a radius ˜100 pc. The emission is primarily in optical and UV, and the radiative luminosity is about 50 per cent of the total kinetic luminosity of the wind. In contrast, the reverse shock in the wind is adiabatic so long as the terminal outflow velocity of the wind vw ≳ 0.003c. The shocked wind in these models radiates in X-rays, but with a luminosity of only ˜1035 erg s-1. For wind velocities vw ≲ 0.001c, the shocked wind becomes radiative, but it is no longer hot enough to produce X-rays. Instead it emits in optical and UV, and the radiative luminosity is comparable to 100 per cent of the wind kinetic luminosity. We suggest that measuring the optical luminosities and putting limits on the X-ray and radio emission from shock-ionized ULX bubbles may help in estimating the mass outflow rate of the central accretion disc and the velocity of the outflow.

  12. Interferometric X-Ray Imaging of Breast Cancer Specimens at 51 keV X-Ray Energy

    Science.gov (United States)

    Takeda, Tohoru; Wu, Jin; Tsuchiya, Yoshinori; Yoneyama, Akio; Lwin, Thet Thet; Aiyoshi, Yuji; Zeniya, Tsutomu; Hyodo, Kazuyuki; Ueno, Ei

    2004-08-01

    The feasibility of the interferometric X-ray imaging technique is examined for revealing the features of breast cancer specimens. The interferometric X-ray imaging system consisted of an asymmetrically cut silicon crystal, a monolithic X-ray interferometer, a phase-shifter, an object cell, and an X-ray CCD camera. Ten 10-mm-thick formalin-fixed breast cancer specimens were imaged at 51 keV, and these images were compared with absorption-contrast X-ray images obtained at 18 keV monochromatic synchrotron X-ray. The interferometric X-ray images clearly depicted the essential features of the breast cancer such as microcalcification down to a size of 0.036 mm, spiculation, and detailed inner soft tissue structures closely matched with histopathological morphology, while the absorption-contrast X-ray images obtained using nearly the same X-ray dose only resolved microcalcification down to a size of 0.108 mm and spiculation. The interferometric X-ray imaging technique can be considered to be an innovative technique for the early and accurate diagnosis of breast cancer using an extremely low X-ray dose.

  13. System for calibration of instruments of x-ray measurement (CIR-X) applying the PGCS; Sistema para calibracion de instrumentos de medicion de rayos X (CIR-X) aplicando el PGCS

    Energy Technology Data Exchange (ETDEWEB)

    Gaytan G, E.; Rivero G, T.; Cruz E, P.; Tovar M, V.M.; Vergara M, F.J. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: egg@nuclear.inin.mx

    2007-07-01

    The Department of Metrology of Ionizing Radiations of the ININ carries out calibration of instruments for X-ray measurement that determine the operation parameters in X-ray diagnostic machines of the health and private sectors. To facilitate this task, the Department of Automation and Instrumentation developed a system for acquisition and signals processing coming from a reference voltage divider with traceability at NIST that is connected directly to the X-rays tube. The system is integrated by the X-ray unit, the X-ray measurement equipment Dynalizer IIIU of RADCAL, a data acquisition card, a personal computer and the acquisition software and signals processing. (Author)

  14. The very soft X-ray emission of X-ray-faint early-type galaxies

    Science.gov (United States)

    Pellegrini, S.; Fabbiano, G.

    1994-01-01

    A recent reanaylsis of Einstein data, and new ROSAT observations, have revealed the presence of at least two components in the X-ray spectra of X-ray faint early-type galaxies: a relatively hard component (kT greater than 1.5 keV), and a very soft component (kT approximately 0.2-0.3 keV). In this paper we address the problem of the nature of the very soft component and whether it can be due to a hot interstellar medium (ISM), or is most likely originated by the collective emission of very soft stellar sources. To this purpose, hydrodynamical evolutionary sequences for the secular behavior of gas flows in ellipticals have been performed, varying the Type Ia supernovae rate of explosion, and the dark matter amount and distribution. The results are compared with the observational X-ray data: the average Einstein spectrum for six X-ray faint early-type galaxies (among which are NGC 4365 and NGC 4697), and the spectrum obtained by the ROSAT pointed observation of NGC 4365. The very soft component could be entirely explained with a hot ISM only in galaxies such as NGC 4697, i.e., when the depth of the potential well-on which the average ISM temperature strongly depends-is quite shallow; in NGC 4365 a diffuse hot ISM would have a temperature larger than that of the very soft component, because of the deeper potential well. So, in NGC 4365 the softest contribution to the X-ray emission comes certainly from stellar sources. As stellar soft X-ray emitters, we consider late-type stellar coronae, supersoft sources such as those discovered by ROSAT in the Magellanic Clouds and M31, and RS CVn systems. All these candidates can be substantial contributors to the very soft emission, though none of them, taken separately, plausibly accounts entirely for its properties. We finally present a model for the X-ray emission of NGC 4365, to reproduce in detail the results of the ROSAT pointed observation, including the Position Sensitive Proportional Counter (PSPC) spectrum and radial

  15. The Correlation between Hard X-Ray Peak Flux and Soft X-Ray Peak Flux in the Outburst Rise of Low-Mass X-Ray Binaries

    NARCIS (Netherlands)

    Yu, W.; van der Klis, M.; Fender, R.P.

    2004-01-01

    We have analyzed Rossi X-Ray Timing Explorer pointed observations of the outbursts of black hole and neutron star soft X-ray transients in which an initial low/hard state, or ``island'' state, followed by a transition to a softer state was observed. In three sources-the black hole transient XTE

  16. Hard X-rays in–soft X-rays out: An operando piggyback view deep into a charging lithium ion battery with X-ray Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Artur, E-mail: artur.braun@alumni.ethz.ch [Laboratory for High Performance Ceramics. Empa, Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Nordlund, Dennis [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94720 (United States); Song, Seung-Wan [Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Huang, Tzu-Wen [Laboratory for High Performance Ceramics. Empa, Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Sokaras, Dimosthenis [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94720 (United States); Liu, Xiasong; Yang, Wanli [Advanced Light Source, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Weng, Tsu-Chien [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94720 (United States); Liu, Zhi [Advanced Light Source, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2015-04-15

    Graphical abstract: - Abstract: For lithium intercalation battery electrodes, understanding of the electronic structure of bulk and surface is essential for their operation and functionality. Soft X-rays are excellent probes for such electronic structure information, but soft X-rays are predominantly surface sensitive and thus cannot probe the bulk. Moreover, soft X-rays hardly permit meaningful in situ and operando studies in battery assemblies. We show here how we penetrate with hard X-rays (>10 keV) in situ a lithium cell, containing a manganite-based cathode. Through X-ray Raman spectroscopy we extract the Mn 2p multiplet from the entire cathode material, thus obtaining bulk-sensitive electronic structure information during battery charging and discharging.

  17. Subgroup report on hard x-ray microprobes

    Energy Technology Data Exchange (ETDEWEB)

    Ice, G.E. [Oak Ridge National Lab., TN (United States); Barbee, T.; Bionta, R. [Lawrence Livermore National Lab., CA (United States); Howells, M.; Thompson, A.C. [Lawrence Berkeley Lab., CA (United States); Yun, W. [Argonne National Lab., IL (United States)

    1994-09-01

    The increasing availability of synchrotron x-ray sources has stimulated the development of advanced hard x-ray (E{>=}5 keV) microprobes. New x-ray optics have been demonstrated which show promise for achieving intense submicron hard x-ray probes. These probes will be used for extraordinary elemental detection by x-ray fluorescence/absorption and for microdiffraction to identify phase and strain. The inherent elemental and crystallographic sensitivity of an x-ray microprobe and its inherently nondestructive and penetrating nature makes the development of an advanced hard x-ray microprobe an important national goal. In this workshop state-of-the-art hard x-ray microprobe optics were described and future directions were discussed. Gene Ice, Oak Ridge National Laboratory (ORNL), presented an overview of the current status of hard x-ray microprobe optics and described the use of crystal spectrometers to improve minimum detectable limits in fluorescent microprobe experiments. Al Thompson, Lawrence Berkeley Laboratory (LBL), described work at the Center for X-ray Optics to develop a hard x-ray microprobe based on Kirkpatrick-Baez (KB) optics. Al Thompson also showed the results of some experimental measurements with their KB optics. Malcolm Howells presented a method for bending elliptical mirrors and Troy Barbee commented on the use of graded d spacings to achieve highest efficiency in KB multilayer microfocusing. Richard Bionta, Lawrence Livermore National Laboratory (LLNL), described the development of the first hard x-ray zone plates and future promise of so called {open_quotes}jelly roll{close_quotes} or sputter slice zone plates. Wenbing Yun, Argonne National Laboratory (ANL), described characterization of jelly roll and lithographically produced zone plates and described the application of zone plates to focus extremely narrow bandwidths by nuclear resonance. This report summarizes the presentations of the workshop subgroup on hard x-ray microprobes.

  18. Calculation of characteristics of X-ray devices

    Directory of Open Access Journals (Sweden)

    Orobinskyi A. N.

    2015-12-01

    Full Text Available Actuality of this work is related to human radiation safety during tuning and regulation of X-ray devices in the process of their development and production. The more precise the calculations for the device are, the less time is required for its tuning and regulation, and thus people are less exposed to radiation. When developing an X-ray device, it is necessary to choose an X-ray tube and filters taking into account the application domain of the device. In order to do this, one should know anode voltage, X-ray tube anode current, material and thickness of filters, i.e. to calculate these characteristics at the set quality of X-ray radiation. The known published studies do not give any solution to this problem. The scientific novelty of this work is that it establishes the interdependence between main characteristics of the X-ray device: the function of the device defines the quality of X-ray radiation (mean photon energy and air kerma power; mean photon energy depends on the X-ray anode tube voltage and spectral resolution; air kerma power depends on anode tube voltage, current of X-ray tube anode, spectral resolution, thicknesses of the filters and their materials; spectral resolution depends on thicknesses of filters and their materials; thickness of filters depends on the material of the filter (the linear coefficient of weakening of X-ray radiation. Knowledge of interdependence of basic characteristics of the X-ray devices allowes developing simple algorithm for their calculation at the values of homogeneity coefficient from 0,8 to 1, which makes it possible to choose an X-ray tube and filters with the purpose of obtaining X-ray radiation of the set quality.

  19. Advanced in X-ray fluorescence holography

    CERN Document Server

    Hayashi, K

    2002-01-01

    X-ray fluorescence holography (XFH) can resolve 'phase problem' in crystal diffraction and therefore it provides 3D atomic images around specific elements. Since first demonstration of the XFH in 1996, view of atoms has been improved rapidly with the refinement of the hologram data collection method. The present performance of the XFH makes it possible to apply to impurity, thin film and quasicrystal, and opens a way to practical tool for determination of local structure. In this paper, theory including solutions for twin image problem, advanced experimental systems and application to Si sub 0 sub . sub 9 sub 9 sub 9 Ge sub 0 sub . sub 0 sub 0 sub 1 are discussed. (author)

  20. X-ray absorption spectroscopy of semiconductors

    CERN Document Server

    Ridgway, Mark

    2015-01-01

    X-ray Absorption Spectroscopy (XAS) is a powerful technique with which to probe the properties of matter, equally applicable to the solid, liquid and gas phases. Semiconductors are arguably our most technologically-relevant group of materials given they form the basis of the electronic and photonic devices that now so widely permeate almost every aspect of our society. The most effective utilisation of these materials today and tomorrow necessitates a detailed knowledge of their structural and vibrational properties. Through a series of comprehensive reviews, this book demonstrates the versatility of XAS for semiconductor materials analysis and presents important research activities in this ever growing field. A short introduction of the technique, aimed primarily at XAS newcomers, is followed by twenty independent chapters dedicated to distinct groups of materials. Topics span dopants in crystalline semiconductors and disorder in amorphous semiconductors to alloys and nanometric material as well as in-sit...

  1. Space Optic Manufacturing - X-ray Mirror

    Science.gov (United States)

    1998-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. This image shows a lightweight replicated x-ray mirror with gold coatings applied.

  2. Polishing X-ray Mirror Mandrel

    Science.gov (United States)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. MSFC's Space Optics Manufacturing Technology Center (SOMTC) has grinding and polishing equipment ranging from conventional spindles to custom-designed polishers. These capabilities allow us to grind precisely and polish a variety of optical devices, including x-ray mirror mandrels. This image shows Charlie Griffith polishing the half-meter mandrel at SOMTC.

  3. Composite materials for x-ray protection

    Energy Technology Data Exchange (ETDEWEB)

    Yaffe, M.J.; Mawdsley, G.E.; Lilley, M.; Servant, R.; Reh, G. (Univ. of Toronto, Ontario, (Canada))

    1991-05-01

    We have developed and tested a radiation protection material that provides similar attenuation for diagnostic x-ray spectra to that of conventional Pb apron materials with approximately 30% reduced weight. By combining a number of elements with different K absorption energies, such as Ba, W, and Pb, energy attenuation for given spectra can be optimized with respect to total cross-sectional mass loading. Alternatively, garments with much higher protective factors at equivalent weight to conventional garments could be produced. The reduction in the amount of Pb used also reduces problems associated with the toxicity of the material during manufacture and disposal. Back strain can be reduced for personnel performing special radiological procedures that require wearing protective garments for long periods of time.

  4. Structure determination by X-ray crystallography

    CERN Document Server

    Ladd, M F C

    1995-01-01

    X-ray crystallography provides us with the most accurate picture we can get of atomic and molecular structures in crystals. It provides a hard bedrock of structural results in chemistry and in mineralogy. In biology, where the structures are not fully crystalline, it can still provide valuable results and, indeed, the impact here has been revolutionary. It is still an immense field for young workers, and no doubt will provide yet more striking develop­ ments of a major character. It does, however, require a wide range of intellectual application, and a considerable ability in many fields. This book will provide much help. It is a very straightforward and thorough guide to every aspect of the subject. The authors are experienced both as research workers themselves and as teachers of standing, and this is shown in their clarity of exposition. There are plenty of iliustrations and worked examples to aid the student to obtain a real grasp of the subject.

  5. Hard x-ray telescope mission

    DEFF Research Database (Denmark)

    Gorenstein, P.; Worrall, D.; Joensen, K.D.

    1996-01-01

    The Hard X-Ray Telescope was selected for study as a possible new intermediate size mission for the early 21st century. Its principal attributes are: (1) multiwavelength observing with a system of focussing telescopes that collectively observe from the UV to over 1 MeV, (2) much higher sensitivity...... and much better angular resolution in the 10 - 100 keV band, and (3) higher sensitivity for detecting gamma ray lines of known energy in the 100 keV to 1 MeV band. This paper emphasizes the mission aspects of the concept study such as the payload configuration and launch vehicle. An engineering team...... at the Marshall Space Center is participating in these two key aspects of the study....

  6. Optical, x-ray and microwave diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Tudisco, S.; Mascali, D.; Altana, C.; Anzalone, A.; Gammino, S.; Musumarra, A.; Musumeci, F.; Scordino, A. [INFN-LNS Via S. Sofia 62, 95123 Catania (Italy); Romano, F. P. [INFN-LNS Via S. Sofia 62, 95123 Catania (Italy); IBAM-CNR, Via Biblioteca 4, 95100 Catania (Italy); Tramontana, A. [INFN-LNS Via S. Sofia 62, 95123 Catania (Italy); Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy)

    2013-07-26

    Laser-driven ion acceleration is a new approach for the particles acceleration, which allows obtaining ion beams with unique properties, such as short burst duration, large particle number, small size source size, low transverse emittance. Currently, two main acceleration mechanisms have been identified and investigated: target normal sheath acceleration (TNSA) and radiation pressure acceleration (RPA). Electrons dynamics and energies are strongly coupled to these acceleration mechanisms and they can be investigated with optical and X-ray techniques. The main aim of these studies are the identification of few physical observables that can be directly correlated to the proton emission obtained (in terms of reproducibility and intensity) in operations with different target material and structure and laser-target interaction parameters.

  7. Dosimetry at X ray examinations of scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Hallen, S.; Martling, K.; Mattsson, S. (Lund Univ. (Sweden). Dept. of Radiation Physics Malmoe General Hospital (Sweden))

    1992-01-01

    Scoliosis is the deformity of the spine that occurs among children, mostly girls, at the age of 10-16 years. The mean absorbed dose to patient examined for scoliosis at three hospitals has been studied in order to determine the radiation risk. The differences in dose between the hospitals are large (a factor of 10 between the mean values and a factor of 100 between highest and lowest patient dose). According to BEIR V (1989), the risk of death from radiation induced cancer for a 15 year old girl is 1.6% per 0.1 Sv. This means 0.2-2 deaths per 1000 scoliosis patients depending on which X ray examination technique is used. (author).

  8. X-ray diffraction with novel geometry

    Energy Technology Data Exchange (ETDEWEB)

    Prokopiou, Danae [Department of Engineering and Applied Science Cranfield University, Shrivenham Campus, Swindon (United Kingdom); Rogers, Keith, E-mail: k.d.rogers@cranfield.ac.uk [Department of Engineering and Applied Science Cranfield University, Shrivenham Campus, Swindon (United Kingdom); Evans, Paul; Godber, Simon [Imaging Science Group, School of Science and Technology, Nottingham Trent University Clifton Campus, Nottingham (United Kingdom); Shackel, James [Department of Engineering and Applied Science Cranfield University, Shrivenham Campus, Swindon (United Kingdom); Dicken, Anthony [Imaging Science Group, School of Science and Technology, Nottingham Trent University Clifton Campus, Nottingham (United Kingdom)

    2014-01-21

    An innovative geometry for high efficiency harvesting of diffracted X-rays is explored. Further to previous work where planar samples were fixed normal to the primary axis, this work extends focal construct geometry (FCG), to samples randomly oriented with respect to the incident beam. The effect of independent sample rotation around two axes upon the scattering distributions was investigated in analytical, simulation and empirical manners. It was found that, although the profile of Bragg maxima were modified when the sample was rotated, high intensity diffraction data was still acquired. Modelling produced a good match to the empirical data and it was shown that the distortions caused by sample rotation were not severe and predictable even when sample rotations were large. The implications for this are discussed.

  9. Multimodal x-ray scatter imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bunk, O; Menzel, A [Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Bech, M; Pfeiffer, F [Department Physik (E17), Technische Universitaet Muenchen, James-Franck-Strausse, 85748 Garching (Germany); Jensen, T H; Feidenhans' l, R [Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark); Binderup, T [Rigshospitalet and Faculty of Health Science, University of Copenhagen, 2100 Copenhagen (Denmark)], E-mail: oliver.bunk@psi.ch

    2009-12-15

    We describe a small-angle x-ray scattering-based imaging technique that reveals the distribution and orientation of nano-scale structures over extended areas. By combining two measurement and analysis schemes, complementary structural information is available which renders the technique suitable for a broad range of applications, e.g. in materials science and bio-imaging. Through a combination of current techniques and on-line analysis schemes, measurements with a so far unprecedented combination of speed, dynamic range and point density became feasible. This is illustrated by data recorded for a section of a mouse soleus muscle visualizing fine muscle and Achilles tendon structures down to the 10 nm range over a 10 mm{sup 2} sample area.

  10. X-ray Studies of Nano Composites

    Science.gov (United States)

    Hexemer, Alexander

    Nano composite materials are an exciting and fast expanding field. X-ray scattering has been used in order to study the structure properties relation. During the last few years the field has expanded more towards the field of thin films where there's been a dramatic increase in the use of grazing incidence small angle X-ray scattering (GISAXS). The main issue of GISAXS has been the complex analysis framework necessary for simulating and fitting. In addition, existing software has restricted the scientist in systems that can be simulated and the speed to analyze large amounts of data. Over the last few years we have worked closely with our computational research and supercomputer division to enable the use of supercomputers to simulate at scattering data. We have developed a comprehensive analysis framework to simulate and fit a wide variety of materials and morphologies. The framework is designed to supply scientists with close to real-time feedback during beam times. Therefore, HipGISAXS (High Performance GISAXS) has been developed to run simulations on massively parallel platforms such as the Oak Ridge Supercomputer Titan (OLCF). Further, with inverse modeling algorithms for fitting available in HipGISAXS, such as particle swarm optimization, it can handle a large number of parameters during the structure fitting process. In September of 2014, HipGISAXS was used in a real time demonstration that married the SAXS/WAXS beamline at the ALS with the data handling and processing capabilities at NERSC, and simulation capabilities of running at-scale simulations on Titan at OLCF. Doe Early Carrier Award, SPOT and CAMERA.

  11. Novel 6MV X-ray photoneutron detection and dosimetry of medical accelerators.

    Science.gov (United States)

    Sohrabi, Mehdi; Hakimi, Amir

    2017-04-01

    Dosimetry of fast, epithermal and thermal photoneutrons in 6MV X-ray beams of two medical accelerators were studied by novel dosimetry methods. A Siemens ONCOR and an Elekta COMPACT medical accelerators were used. Fast, epithermal and thermal photoneutron dose equivalents in 10cm×10cm 6MV X-rays fields were determined in air and on surface of a polyethylene phantom in X and Y directions. Polycarbonate dosimeters as bare or with enriched 10B convertors (with or without cadmium covers) were used applying a 50Hz-HV electrochemical etching method. Fast, epithermal and thermal photoneutron dose equivalents were efficiently determined respectively as ∼1145.8, ∼45.3 and ∼170.6μSv in air and ∼1888.5, ∼96.1 and ∼640.6μSv on phantom per 100Gy X-rays at the isocenter of Siemens ONCOR accelerator in air. The dose equivalent is maximum at the isocenter which decreases as distance from it increases reaching a constant level. Tissue-to-air ratios are constants up to 15cm from the isocenter. No photoneutrons was detected in the Elekta COMPACT accelerator. Fast, epithermal and thermal photoneutron dosimetry of 6MV X-rays were made by novel dosimetry methods in a Siemens ONCOR accelerator with sum dose equivalent per Gy of ∼0.0014% μSv with ∼0.21MeV mean energy at the isocenter; i.e. ∼150 times smaller than that of 18MV X-rays. This observation assures clinical safety of 6MV X-rays in particular in single-mode machines like Elekta COMPACT producing no photoneutrons due to no "beryllium exit window" in the head structure. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  12. Identifying Bright X-Ray Beasts

    Science.gov (United States)

    Kohler, Susanna

    2017-10-01

    Ultraluminous X-ray sources (ULXs) are astronomical sources of X-rays that, while dimmer than active galactic nuclei, are nonetheless brighter than any known stellar process. What are these beasts and why do they shine so brightly?Exceeding the LimitFirst discovered in the 1980s, ULXs are rare sources that have nonetheless been found in all types of galaxies. Though the bright X-ray radiation seems likely to be coming from compact objects accreting gas, theres a problem with this theory: ULXs outshine the Eddington luminosity for stellar-mass compact objects. This means that a stellar-mass object couldnt emit this much radiation isotropically without blowing itself apart.There are two alternative explanations commonly proposed for ULXs:Rather than being accreting stellar-mass compact objects, they are accreting intermediate-mass black holes. A hypothetical black hole of 100 solar masses or more would have a much higher Eddington luminosity than a stellar-mass black hole, making the luminosities that we observe from ULXs feasible.An example of one of the common routes the authors find for a binary system to become a ULX. In this case, the binary begins as two main sequence stars. As one star evolves off the main sequence, the binary undergoes a common envelope phase and a stage of mass transfer. The star ends its life as a supernova, and the resulting neutron star then accretes matter from the main sequence star as a ULX. [Wiktorowicz et al. 2017]They are ordinary X-ray binaries (a stellar-mass compact object accreting matter from a companion star), but they are undergoing a short phase of extreme accretion. During this time, their emission is beamed into jets, making them appear brighter than the Eddington luminosity.Clues from a New DiscoveryA few years ago, a new discovery shed some light on ULXs: M82 X-2, a pulsing ULX. Two more pulsing ULXs have been discovered since then, demonstrating that at least some ULXs contain pulsars i.e., neutron stars as the

  13. Identifying wrist fracture patients with high accuracy by automatic categorization of X-ray reports.

    Science.gov (United States)

    de Bruijn, Berry; Cranney, Ann; O'Donnell, Siobhan; Martin, Joel D; Forster, Alan J

    2006-01-01

    The authors performed this study to determine the accuracy of several text classification methods to categorize wrist x-ray reports. We randomly sampled 751 textual wrist x-ray reports. Two expert reviewers rated the presence (n = 301) or absence (n = 450) of an acute fracture of wrist. We developed two information retrieval (IR) text classification methods and a machine learning method using a support vector machine (TC-1). In cross-validation on the derivation set (n = 493), TC-1 outperformed the two IR based methods and six benchmark classifiers, including Naive Bayes and a Neural Network. In the validation set (n = 258), TC-1 demonstrated consistent performance with 93.8% accuracy; 95.5% sensitivity; 92.9% specificity; and 87.5% positive predictive value. TC-1 was easy to implement and superior in performance to the other classification methods.

  14. Effect of X-ray exposure on the pharmaceutical quality of drug tablets using X-ray inspection equipment.

    Science.gov (United States)

    Uehara, Kazuaki; Tagami, Tatsuaki; Miyazaki, Itaru; Murata, Norikazu; Takahashi, Yoshifumi; Ohkubo, Hiroshi; Ozeki, Tetsuya

    2015-06-01

    X-ray inspection equipment is widely used to detect missing materials and defective goods in opaque containers. Its application has been expanded to the pharmaceutical industry to detect the presence of drug tablets in aluminum foil press-through packaging. However, the effect of X-rays on the pharmaceutical quality of drug tablets is not well known. In this study, the effect of X-rays on the pharmaceutical quality of drug tablets was investigated. Exposure of acetaminophen, loxoprofen and mefenamic acid tablets to X-ray doses of 0.34 mGy (thrice the dose by X-ray scanning) to 300 Gy (maximum dose from our X-ray equipment) was demonstrated, and the samples were evaluated by formulation tests. Exposure to X-rays did not affect the pharmaceutical quality of the drug content. The samples exposed to X-rays exhibited almost the same profile in formulation tests (dissolution test, disintegrating test and hardness test) as control samples (0 Gy). The combination of X-ray exposure with accelerated temperature and humidity tests (six months) also did not affect the pharmaceutical quality. The color change of light-sensitive drugs (nifedipine and furosemide tablets) after X-ray exposure was negligible (drug tablets.

  15. X-rays and photocarcinogenesis in hairless mice

    DEFF Research Database (Denmark)

    Lerche, Catharina M; Philipsen, Peter A; Wulf, Hans Christian

    2013-01-01

    It is well known that excessive X-ray radiation can cause non-melanoma skin cancers. With the increased incidence of sun-related skin cancer there is a need to investigate the combination of sunlight and X-rays. Immunocompetent C3.Cg/TifBomTac mice (n = 298) were divided into 12 groups. Mice were...... irradiated with 12, 29 or 50 kV X-rays. The mice received a total dose of 45 Gy. They were irradiated with 3 SED simulated solar radiation (SSR) either before or after irradiation with X-rays. The groups irradiated with X-rays alone, 0, 3, 9 and 10 mice (0, 12, 29 and 50 kV, respectively) developed squamous...... cell carcinoma. In the groups irradiated with SSR after X-rays the development of tumours was significantly faster in the 50 kV group than in the corresponding control group (175 vs. 194 days, p...

  16. Fabrication process for a gradient index x-ray lens

    Science.gov (United States)

    Bionta, Richard M.; Makowiecki, Daniel M.; Skulina, Kenneth M.

    1995-01-01

    A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

  17. The Beginnings of Stellar X-Ray Astronomy

    Science.gov (United States)

    Rosner, R.

    2000-09-01

    I review the beginnings of the field of stellar X-ray astronomy, concentrating on the period immediately preceeding, and immediately following, the launch of the Einstein Observatory. The wealth of data was such that, within the first two years following launch, major discoveries were made by scientists from both the Einstein Observatory PI groups and Einstein Observatory Guest Observers which established stellar X-ray astronomy as a new astronomical discipline: Discovery of early and late-type stars, as well as young protostars, as soft X-ray sources; discovery of the "dividing line" separating X-ray emitting and X-ray quiet giant and supergiant stars; and establishment of the "solar-stellar connection" as a paradigm for understanding X-ray emission from late-type stars.

  18. Adjustable Grazing-Incidence X-Ray Optics

    Science.gov (United States)

    O'Dell, Stephen L.; Reid, Paul B.

    2015-01-01

    With its unique subarcsecond imaging performance, NASA's Chandra X-ray Observatory illustrates the importance of fine angular resolution for x-ray astronomy. Indeed, the future of x-ray astronomy relies upon x-ray telescopes with comparable angular resolution but larger aperture areas. Combined with the special requirements of nested grazing-incidence optics, mass, and envelope constraints of space-borne telescopes render such advances technologically and programmatically challenging. The goal of this technology research is to enable the cost-effective fabrication of large-area, lightweight grazing-incidence x-ray optics with subarcsecond resolution. Toward this end, the project is developing active x-ray optics using slumped-glass mirrors with thin-film piezoelectric arrays for correction of intrinsic or mount-induced distortions.

  19. Application of kinoform lens for X-ray reflectivity analysis.

    Science.gov (United States)

    Tiwari, M K; Alianelli, L; Dolbnya, I P; Sawhney, K J S

    2010-03-01

    In this paper the first practical application of kinoform lenses for the X-ray reflectivity characterization of thin layered materials is demonstrated. The focused X-ray beam generated from a kinoform lens, a line of nominal size approximately 50 microm x 2 microm, provides a unique possibility to measure the X-ray reflectivities of thin layered materials in sample scanning mode. Moreover, the small footprint of the X-ray beam, generated on the sample surface at grazing incidence angles, enables one to measure the absolute X-ray reflectivities. This approach has been tested by analyzing a few thin multilayer structures. The advantages achieved over the conventional X-ray reflectivity technique are discussed and demonstrated by measurements.

  20. Dark field X-ray microscopy for studies of recrystallization

    DEFF Research Database (Denmark)

    Ahl, Sonja Rosenlund; Simons, Hugh; Jakobsen, Anders Clemen

    2015-01-01

    We present the recently developed technique of Dark Field X-Ray Microscopy that utilizes the diffraction of hard X-rays from individual grains or subgrains at the (sub)micrometre- scale embedded within mm-sized samples. By magnifying the diffracted signal, 3D mapping of orientations and strains...... external influences. The capabilities of Dark Field X- Ray Microscopy are illustrated by examples from an ongoing study of recrystallization of 50% cold-rolled Al1050 specimens....