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X-ray phase-contrast imaging is a powerful imaging modality for non-destructive visualisation of weakly-absorbing materials inside an object. We present here a two-directional beam-tracking approach for phase-contrast imaging in a laboratory setup. A single absorption mask is used to modulate the polychromatic x-ray beam, and the divergence of the beam is exploited to analyse the beamlets with detector pixels comparable in size to the mask pitch. The method gives access to two orthogonal phase gradients, which allows for robust phase integration. Two implementations are demonstrated: one with a low-noise photon-counting device for radiography, and the other with an indirect conversion flat-panel detector for phase-contrast tomography. Finally, images of biological specimens are presented to show the potential of the approach for biomedical applications. [ABSTRACT FROM AUTHOR]

When solving the problems of producing high-quality seeds and grains, it is necessary to study the mechanisms of their production when grown using various agricultural technologies. For its implementation, it is most effective to use the method of digital radiography, estimating the content in the batch of the proportion of seeds with various types of hidden defects when conducting precision experiments, when selecting high-quality grain batches in industrial grain production, it is necessary to develop regulatory documents for the permissible level of latent injury. This methodological approach will allow ranking different varieties according to the degree of latent injury of seed material, as well as correcting technological regimes in the production of grain in order to minimize the indicator of latent defects that affect the economic suitability of seeds and grain. [ABSTRACT FROM AUTHOR]

To ensure the high quality of the resulting image, a radiographic device must be tested for suitability by an exposure test with the aim of achieving calibration. The X-ray radiographic exposure test is very important. X-rays have large ionizing and penetrating powers so X-ray radiation is very dangerous for the body. Therefore the use of phantoms is very important in the exposure test of a radiographic device that uses X-rays so as not to directly experiment with humans. Making phantoms in the medical world is quite expensive, so resin-based phantoms are used which are easily available in the market. Therefore, it is necessary to know the effectiveness of resin with different density substances as a substitute for human soft tissue phantom in the detection of low contrast objects. Phantom resin with exposed fill is for testing using X-ray radiographic modality. The image obtained is then analyzed. Obtained the higher the current used, the higher the value of contrast and the resulting CNR. Increase in contrast occurs in all objects. This shows that the material used as a resin maker can be stable in changing currents. From the results obtained, the phantoms made are sufficient to be used for low contrast tests on radiographs. [ABSTRACT FROM AUTHOR]

When a patient is exposed to ionizing radiation from X-rays generated by an ionizing radiation generator, there is a known diagnostic dose guide. Ionizing radiation given to patients in diagnostic and interventional radiology activities must also follow the rules or guidelines given according to the standards of radiation protection and safety principles. In accordance with the optimization principle in radiation protection and safety, we should always try to keep the dose received by the patient as low as possible without compromising the image quality by considering social and economic factors. To enforce optimization in the use of ionizing radiation, especially in the fields of diagnostic and interventional radiology, cooperation from all relevant stakeholders, both the Regulatory Agency and the permit holder (PI) is required. In addition, there are several media that can be used to assist in implementing optimization efforts. Currently, one of the effective tools recommended by the International Atomic Energy Agency (IAEA) in enforcing optimization for patients is to establish and implement a Diagnostic Reference Level (DRL) both at the local and national levels. Based on the literature it is known that the guidelines for diagnostic radiology were first found in the Decree of the Head of BAPETEN Number 01-P/Ka-BAPETEN/I-03 concerning Guidelines for Radiodiagnostic Patient Doses. Then the value of the guide developed and became available in the Regulation of the Head of BAPETEN Number 8 of 2011 concerning Radiation Safety in the Use of Diagnostic and Interventional Radiology X-Rays, and finally we have our own level of diagnostic guidance in accordance with national resources and infrastructure as stipulated in BAPETEN Decree Number 1211/K/V/2021 concerning the Indonesian Diagnostic Reference Level Assessment for CT-Scan and General Radiography X-Ray Modalities. The availability of the value of the diagnostic guide level is one of the efforts of the Indonesian state in applying the principles of radiation protection and safety. One of the principles of radiation protection and safety is optimization of radiation protection carried out on patients for several types of diagnostic radiological examinations. [ABSTRACT FROM AUTHOR]

This work is aimed at evaluating the organs doses for adult patients undergoing chest radiographic examination (PA) in Al Najaf chosen hospitals (Iraq). The organs doses were evaluated for 83 patients of undergoing PA chest radiography by utilizing CALDOSE computing program. The organ dose calculations were relied on the output of the X-ray tube measurements and exposure parameters data. Four X-ray units were considered to estimate the patients' organs doses. Four hospitals were considered in this research (i.e. Al-Sadder hospital (ASH), Al-Hakeem hospital (AHH), Al-Furat hospital (AFH) and Al-Zahra hospital (AZH)). The tube potential (kVp) set for PA chest X-ray was ranged from 72.35±9.83 kVp in AZH to 82.05 ± 9.67 kVp in AHH; tube loading (mAs) was ranged from 1.55±0.87 mAs in ASH to 26.72±2.8 mAs in AZH, while the SID range was between 143.14±3.29 cm and 164.47±11.4 cm. The corresponding can be seen that the highest average organ dose was 0.16 mGy the lungs received in AZH, while the lungs was received the lowest dose at 0.012 mGy in AHH across hospitals. A clear variation for the organ's doses were noticed across different hospitals even with using similar facilities reflecting variable radiographic practice for the same examination. In AZH, organs doses were generally higher than those other X-ray units of this study; and were comparable to those published by some states (e.g. USA and Brazil). Finally, achieving a regular quality control (QC) investigation with dose audit is largely required. [ABSTRACT FROM AUTHOR]

It is shown that internal defects of food grains can be determined by X-ray. A methodology for microfocus radiography using modern equipment has been developed. The methodology makes it possible to identify and quantify defective grain with internal (hidden) defects in wheat lots. [ABSTRACT FROM AUTHOR]

The paper demonstrates the features of software development for CCD-lines X-CARD DE & SE manufactured by Detection Technology. The modes of operation of it in various states and their description are given. The article demonstrates the ability to create an X-ray detector based on the above CCD arrays. [ABSTRACT FROM AUTHOR]

Various methods of diagnostics of their quality are used for evaluation of biological completeness of economic suitability of individual seeds in precision experiments, as well as for selection of household-suitable lots of seeds in controlled industrial seed production, including method of soft-beam microfocus X-ray radiography. Existing traditional approaches (testing of germination in laboratory conditions) do not allow to assess the economic suitability of seeds in field conditions, as for this purpose it is necessary to use a comprehensive assessment of the quality of seed material taking into account its hidden damage. [ABSTRACT FROM AUTHOR]

X-ray multi-energy adaptive security radiography and computed tomography inspection techniques have superior performance compared to conventional dual-energy methods where two image slices are acquired by alternating energies. This new technique allows improving the quality of radiographic and CT images, expanding the range of areal densities of the interrogated objects over which effective discrimination of materials by atomic number is possible, eliminating artifacts in the image of boundaries of different densities, and reducing the time of inspection and the required dose. For this new inspection technology, RadiaBeam Technologies is developing several new types of x-ray sources that are based on linear electron accelerators. To provide an adaptive mode of operation of inspection systems, such accelerators use fast feedback from the detector array. Depending on the application, the range of the electron energy can vary from 180 keV up to 9 MeV. In this paper, we discuss the requirements for such linear accelerators, some details about their designs, and present the results of high-power and beam testing of the S- and X- band accelerators. [ABSTRACT FROM AUTHOR]

Historians and librarians are interested in watermarks and mould surface patterns in historic papers, because they represent the “fingerprints” of antique papers. However, these features are usually covered or hidden by printing, writing or other media. Different techniques have been developed to extract the watermarks in the paper while avoiding interference from media on the paper. Beta radiography provides good results, but this method cannot be widely used because of radiation safety regulations and the long exposure times required due to weak isotope sources employed. In this work, two promising methods are compared which can be used to extract digital high-resolution images for paper watermarks and these are electron radiography and low energy X-ray radiography. For electron radiography a “sandwich” of a lead sheet, the paper object, and a film in a dark cassette, is formed and it is exposed at higher X-ray potentials (> 300 kV). The photoelectrons escaping from the lead sheet penetrate the paper and expose the film. After development, the film captures the watermark and mould surface pattern images for the paper being investigated. These images are then digitized using an X-ray film digitizer. The film employed could potentially be replaced by a special type of imaging plate with a very thin protection layer to directly generate digital images using computed radiography (CR). For the second method, a low energy X-ray source is used with the specimen paper placed on a digital detector array (DDA). This method directly generates a low energy digital radiography (DR) image. Both methods provide high quality images without interference from the printing media, and provide the potential to generate a “fingerprint” database for historical papers. There were nevertheless found to be differences in the images obtained using the two methods. The second method, using a low energy X-ray source, has the potential to be integrated in a portable device with a small footprint incorporating user safety requirements. Differences obtained using the two methods are shown and discussed. [ABSTRACT FROM AUTHOR]

Radiography is the basis for the diagnosis of infants with extremely low body weight, but none of the existing types of X-ray machines cannot fully meet all the requirements for technical means of X-ray diagnostics in the non-specialized conditions. In this paper results of the work to create a method of X-ray diagnostic studies in non-specialized conditions, including the development of X-ray optical imaging scheme, methods of laying the patient during X-ray photography, as well as technical means of X-ray are described. [ABSTRACT FROM AUTHOR]

Digital Detector Arrays (DDA) are increasingly replacing film in radiography applications. Standards exist for characterizing the performance of these detectors, and for using them in specific inspections. We have observed that the selection of the x-ray source to use with these detectors can also have a significant influence on the performance. We look at differences between standard, and micro-focus x-ray tubes, and end-window vs. side-window micro-focus tubes. We find that for best results, one must calibrate the DDA for the source settings used during an inspection. This is particularly true for variable-focus sources. [ABSTRACT FROM AUTHOR]

Often a newborn presents breathing problems during the early days of life, i.e. bronchopneumonia, wich are caused in most of cases, by aspirating a mixture of meconium and amniotic fluid. In these cases, it is necessary to make use of a radiograph, requested by the physician to reach a diagnosis. This paper seeks to evaluate the absorbed doses in neonates undergoing a radiograph. For this reason we try to simulate the real conditions in a X-ray room from Lima hospitals. With this finality we perform a simulation made according a questionnaire related to technical data of X-ray equipment, distance between the source and the neonate, and its position to be irradiated. The information obtained has been used to determine the absorbed dose by infants, using the MCNP code. Finally, the results are compared with reference values of international health agencies. [ABSTRACT FROM AUTHOR]

We describe a technique for measuring the pressure and density of a metallic solid, shocklessly compressed to multi-megabar pressure, through x-ray radiography of a magnetically driven, cylindrical liner implosion. Shockless compression of the liner produces material states that correspond approximately to the principal compression isentrope (quasi-isentrope). This technique is used to determine the principal quasi-isentrope of solid beryllium to a peak pressure of 2.4 Mbar from x-ray images of a high current (20 MA), fast (~100 ns) liner implosion. [ABSTRACT FROM AUTHOR]

“X-Ray Astronomy 2009,” a gathering of high-energy astrophysicists from around the world, rightly celebrates a rich and productive scientific discipline spanning some 50-odd years. The participants include everyone from the pioneers of X-ray astronomy to young scientists just starting out. The data described in this meeting come from hundreds of projects by citizens from dozens of countries. By any measure, X-ray astronomy has been and continues to be an important field with strong impact on our understanding of the cosmos. [ABSTRACT FROM AUTHOR]

Multilayer Laue Lenses (MLLs) were developed by us using dynamic diffraction effects to efficiently focus hard x-rays to very small spots. Using a partial MLL we were able to focus 19.5-keV hard x-rays to a line focus of 16 nm with an efficiency of 31%. A full MLL is a complete linear MLL structure. It can be fabricated by bonding two partial MLL wafers, or by growing the full structure using magnetron sputtering without bonding. A 40-μm full MLL, with a total of 5166 layers of WSi2 and Si, has been successfully grown by sputter deposition. The layer thicknesses gradually vary from 4 nm to ∼400 nm and then back to 4 nm. Two coating runs were used to grow the full structure, one for each half. It took over 56 h for each run. A 100-μm nearly-full MLL was constructed by bonding. Each 50-μm half-structure has 1788 WSi2 and Si layers with 12-nm to ∼32-nm thicknesses and ∼32-μm total thickness, followed by a thick WSi2 layer of ∼17 μm, and an AuSn layer of ∼1 μm. Both full MLL structures survived dicing and polishing. The primary results demonstrate the feasibility and potential of a full MLL with a doubled numerical aperture and large beam acceptance for hard x-rays. [ABSTRACT FROM AUTHOR]

In this paper, possibility of creation of three-dimensional crack models, both random type and based on real-life radiographic images is discussed. Method for storing cracks in a number of two-dimensional matrices, as well algorithm for their reconstruction into three-dimensional objects is presented. Also the possibility of using iterative algorithm for matching simulated images of cracks to real-life radiographic images is discussed. [ABSTRACT FROM AUTHOR]

We present the results of a study on the optical and X-ray variability properties of eight Seyfert galaxies NGC 5548, NGC 7469, NGC 4051, NGC 4151, NGC 3227, Ark 564, Mrk 509, Mrk 79. Two objects, NGC 5548 and NGC 4051, show the highest probability for the positive lag (i.e., optical variations lag behind the X-ray) at about 97% confidence level. The lag is found to be 2.8-1.0+3.7 days for NGC 5548 and 2.1-0.4+3.9 days for NGC 4051 that testifies in favor of the re-radiation mechanism by Compton upscattering. Two objects, NGC 5548 and NGC 7469, show the highest degree of correlation between optical and X-ray fluxes, though this correlation is lower for other objects, and completely absent for Ark 564. The width of the auto-correlation function and the slope of the structure function are greater for the optic light curves than for X-ray light curves. It means the rapid flux variations are manifested better in the X-rays, while the long-term variations are manifested better in optical bands. We discuss also the first results of studying the kinematic and photometric properties of AGNs selected from the new 2 MIG (2-Micron Isolated Galaxies) catalogue for estimating environmental influence in case of AGNs with companions. [ABSTRACT FROM AUTHOR]

Digital Speckle Radiography (DSR) is a technique allowing full field displacement maps in a plan within an opaque material to be determined. The displacements are determined by tracking the motions of small sub-sections of a deforming speckle pattern, produced by seeding an internal layer of lead and taking flash x-ray images. An improved DSR algorithm is discussed which can improve the often poor contrast in DSR images, such that the mean and variance of the speckle pattern is uniform. This considerably improves the correlation success relative to other similar algorithms for DSR experiments. A series of experiments involving the penetration of granular media by long-rod projectiles, and the improved correlation achieved using this new algorithm, are discussed. [ABSTRACT FROM AUTHOR]

The evolution of a thermally-initiated explosion is studied using a multiple-image x-ray system. HMX-based PBX 9501 is used in this work, enabling direct comparison to recently-published data obtained with proton radiography [1]. Multiple x-ray images of the explosion are obtained with image spacing of ten microseconds or more. The explosion is simultaneously characterized with a high-speed camera using an interframe spacing of 11 μs. X-ray and camera images were both initiated passively by signals from an embedded thermocouple array, as opposed to being actively triggered by a laser pulse or other external source. X-ray images show an accelerating reacting front within the explosive, and also show unreacted explosive at the time the containment vessel bursts. High-speed camera images show debris ejected from the vessel expanding at 800–2100 m/s in the first tens of μs after the container wall failure. The effective center of the initiation volume is about 6 mm from the geometric center of the explosive. [ABSTRACT FROM AUTHOR]

To understand the so-called excess noise, we measured the complex impedance of a TES microcalorimeter, and derived the hernial sensitivity α, current sensitivity β, and heat capacity C. Making use of the obtained parameters, we found that the excess noise can be represented by two types of extra noise having similar spectra as Johnson and phonon noise. The contribution of the Johnson-like, usually expressed by the M factor, depended on α [formula] which is consistent with the behavior of the excess noise studied in other groups. Pursuing the better energy resolution, we suppressed the dominant noise components by introducing a Si collimator to irradiate X-rays only to the Au absorber, increasing the ADC resolution, and improving the temperature stability. So far, the energy resolution has been improved from 4.8 eV to 2.8 eV (FWHM). [ABSTRACT FROM AUTHOR]

An X-pinch device and the related diagnostics of x-ray emission from X-pinch were briefly described. The time-resolved x-ray measurements with photoconducting diodes show that the x-ray pulse usually consists of two subnanosecond peaks with a time interval of about 0.5 ns. Being consistent with these two peaks of the x-ray pulse, two point x-ray sources of size ranging from 100 μm to 5 μm and depending on cut-off x-ray photon energy were usually observed on the pinhole pictures. The x-pinch was used as x-ray source for backlighting of the electrical explosion of single wire and the evolution of X-pinch, and for phase-contrast imaging of soft biological objects such as a small shrimp and a mosquito. [ABSTRACT FROM AUTHOR]

Four new technologies have been developed for use in non-intrusive inspection systems to detect nuclear materials, explosives and contraband. Nuclear Resonance Fluorescence (NRF) provides a three dimensional image of the isotopic content of a container. NRF determines the isotopic composition of a region and specifies the isotopic structure of the neighboring regions, thus providing the detailed isotopic composition of any threat. In transmission mode, NRF provides a two dimensional projection of the isotopic content of a container, much as standard X-ray radiography provides for density. The effective-Z method (EZ-3D™) uses electromagnetic scattering processes to yield a three-dimensional map of the effective-Z and the density in a container. The EZ-3D™ method allows for a rapid discrimination based on effective Z and mass of materials such as those with high Z, as well as specifying regions of interest for other contraband. The energy spectrum of prompt neutrons from photon induced fission (PNPF) provides a unique identification of the presence of actinides and SNM. These four new technologies can be used independently or together to automatically determine the presence of hazardous materials or contraband. They can also be combined with other technologies to provide added specificity. [ABSTRACT FROM AUTHOR]

The detection and interdiction of concealed special nuclear material (SNM) in all modes of transport is one of the most critical security issues facing the United States and the rest of the world. In principle, detection of nuclear materials is relatively easy because of their unique properties: all of them are radioactive and all emit some characteristic gamma rays. A few emit neutrons as well. These signatures are the basis for passive non-intrusive detection of nuclear materials. The low energy of the radiations necessitates additional means of detection and validation. These are provided by high-energy x-ray radiography and by active inspection based on inducing nuclear reactions in the nuclear materials. Positive confirmation that a nuclear material is present or absent can be provided by interrogation of the inspected object with penetrating probing radiation, such as neutrons and photons. The radiation induces specific reactions in the nuclear material yielding, in turn, penetrating signatures which can be detected outside the inspected object. The “conventional” signatures are first and foremost fission signatures: prompt and delayed neutrons and gamma rays. Their intensity (number per fission) and the fact that they have broad energy (non-discrete, though unique) distributions and certain temporal behaviors are key to their use. The “non- conventional” signatures are not related to the fission process but to the unique nuclear structure of each element or isotope in nature. This can be accessed through the excitation of isotopic nuclear levels (discrete and continuum) by neutron inelastic scattering or gamma resonance fluorescence. Finally there is an atomic signature, namely the high atomic number (Z>74), which obviously includes all the nuclear materials and their possible shielding. The presence of such high-Z elements can be inferred by techniques using high-energy x rays. The conventional signatures have been addressed in another article. Non-conventional signatures and some of their current or potential uses will be discussed here. [ABSTRACT FROM AUTHOR]

We are studying the use of 0.1–1.0 GeV laser-accelerated electron beams as active interrogation probes for long-standoff radiography or nuclear activation of concealed special nuclear material. Use of beams in this energy range is largely unexplored, but such beams could provide notable advantages over lower-energy beams and x-rays. High-energy laser-accelerated electrons exhibit large penetration range through air and solids, and low beam divergence for both direct beams and secondary Bremsstrahlung x-rays. We present laboratory measurements of radiography and activation, using the high-power Diodes laser system at the University of Nebraska, as well as MCNP and GEANT Monte Carlo simulation results used to aid experiment design and interpretation. [ABSTRACT FROM AUTHOR]

Diffraction and transmission synchrotron imaging methods have proven to be highly suitable for investigations in materials research and non-destructive evaluation. The high flux and spatial coherence of X-rays from modern synchrotron light sources allows one to work using high resolution and different contrast modalities. This article gives a short overview of different transmission and diffraction imaging methods with high potential for industrial applications, now available for commercial access via the German light source ANKA (Forschungszentrum Karlsruhe) and its new department ANKA Commercial Service (ANKA COS, http://www.anka-cos.de). [ABSTRACT FROM AUTHOR]

The methods of nondestructive testing (NDT) are generally ultrasonic, neutron, eddy-current and X-rays, NDT by using X-rays, in particular, is the most useful inspection technique having high resolution. We can especially evaluate corroded pipes of petrochemical complex, nuclear and thermal-power plants by the high energy X-ray NDT system. We develop a portable X-ray NDT system with X-band linac and magnetron. This system can generate a 950 keV electron beam. We are able to get X-ray images of samples with 1 mm spatial resolution. This system has application to real time impeller inspection because linac based X-ray sources are able to generate pulsed X-rays. So, we can inspect the rotating impeller if the X-ray pulse rate is synchronized with the impeller rotation rate. This system has application in condition based maintenance (CBM) of nuclear plants, for example. However, 950 keV X-ray source can only be used for thin tubes with 20 mm thickness. We have started design of a 3.95 MeV X-band linac for broader X-ray NDT application. We think that this X-ray NDT system will be useful for corrosion wastage and cracking in thicker tubes at nuclear plants and impeller of larger pumps. This system consists of X-band linac, thermionic cathode electron gun, magnetron and waveguide components. For achieving higher electric fields the 3.95 MeV X-band linac structure has the side-coupled acceleration structure. This structure has more efficient acceleration than the 950 keV linac with alternating periodic structure (APS). We adopt a 1.3 MW magnetron for the RF source. This accelerator system is about 30 cm long. The beam current is about 150 mA, and X-ray dose rate is 10 Gy@1 m/500 pps. In this paper, the detail of the whole system concept and the electromagnetic field of designed linac structure will be reported. [ABSTRACT FROM AUTHOR]

The laser accelerator provides us not only ultra high field, but also extremely short pulse radiation sources, the laser-produced X-rays. Using a 1.2 TW table-top Ti:sap laser, we are pursuing the activities for the industrial application. First we proposed a new injection acceleration scheme using the ultra short beat-wave accelerator for the economical radiation source. Then we proposed two applications both on the backward see-through vision of distant objects using the laser X-rays, and on the X-ray illumination on Aspergillus awamori spores, which is 100 times effective of the current X-ray tube cases. [ABSTRACT FROM AUTHOR]

An overview of the plasma based sources of energetic photons, ranging from UV to hard X-rays, developed in GREMI is proposed. Each source principle is shortly described and applications of these specially designed sources are documented. The possibility of producing energetic photons over a very broad wavelength domain, together with the versatility of the mode of operations allow for a very large range of applications. The matching of the photon energy, the pulse repetition rate, the short duration, of a few nanosecond, of photon pulses offer for instance unique possibility for fast dynamic study, low Z element spray characterization, X-ray fluorescence of dense targets, lithography issues, and UV VUV radiating plasma optimization. [ABSTRACT FROM AUTHOR]

Using a white x-ray synchrotron beam, we have dynamically studied radiation-induced decomposition in single crystalline PETN and TATB. By monitoring the integrated intensity of selected diffraction spots via a CCD x-ray camera as a function of time, we have found that the decomposition rate varies dramatically depending upon the orientation of the crystalline axes relative to polarized x-ray beam and for differing diffracting conditions (spots) within the same crystalline orientation. We suggest that this effect is due to Compton scattering of the polarized x-rays with electron clouds that is dependent upon their relative orientation. This novel effect may yield valuable insight regarding anisotropic detonation sensitivity in energetic materials such as PETN. [ABSTRACT FROM AUTHOR]

Three new capabilities have recently been commissioned at the proton radiography [1] facility at Los Alamos. A powder gun driver system has been installed and commissioned and a series of demonstration measurements have been completed. This powder gun is now regularly used to drive dynamic experiments. A new CMOS hybrid camera technology has been developed and fielded resulting in dramatic improvements in quantum efficiency as well as providing eight additional radiographic images per dynamic event. A proton x3 magnifier was designed, built and commissioned to provide improved radiographic resolution for 800 MeV proton radiography experiments. Details of these new capabilities will be presented along with data from recent experiments which utilized these new capabilities. [ABSTRACT FROM AUTHOR]

Modelling of off-Hugoniot states in an expanding interface subjected to a shock reveals the importance of a chemically complete description of the materials. Hydrodynamic experiments typically rely on pre-shot target characterization to predict how initial perturbations will affect the late-time hydrodynamic mixing. However, it is the condition of these perturbations at the time of shock arrival that dominates their eventual late-time evolution. In some cases these perturbations are heated prior to the arrival of the main shock. Correctly modelling how temperature and density gradients will develop in the pre-heated material requires an understanding of the equation-of-state. In the experiment modelled, an epoxy/foam layered package was subjected to tin L-shell radiation, producing an expanding assembly at a well-defined temperature. This assembly was then subjected to a controlled shock, and the evolution of the epoxy-foam interface imaged with x-ray radiography. Modelling of the data with the hydrodynamics code RAGE was unsuccessful under certain shock conditions, unless condensation of chemical species from the plasma is explicitly included. The EOS code Cheetah was used to prepare suitable EOS for input into the hydrodynamics modelling. [ABSTRACT FROM AUTHOR]

XMM-Newton and Chandra observations of quasars suggest the presence of high-velocity outfiows of ionized absorbing material with mass-outflow rates of up to a few M⊙ yr-1 that are considerably higher than those based on the wind properties derived from UV BALs. Quasar winds might be more powerful than what we previously thought. X-ray absorption lines produced by outfiowing material detected in several quasars are possibly probing a highly ionized and high velocity component of the accretion disk wind that appears to be distinct from the absorbers detected in the optical and UV wavebands. We present X-ray absorption line diagnostics that allow us to constraint the properties of the outfiowing wind in quasars. [ABSTRACT FROM AUTHOR]

High-energy x-ray backlighters will be valuable for radiography experiments at the National Ignition Facility (NIF), and for radiography of imploded inertial confinement fusion cores using Compton scattering to observe cold, dense plasma. Key considerations are the available backlight brightness, and the backlight size. To quantify these parameters we have characterized the emission from low- and high-Z planar foils irradiated by intense picosecond and femtosecond laser pulses from the TITAN laser facility at Lawrence Livermore National Laboratory. Spectra generated by a sequence of elements from Mo to Pb, spanning the x-ray energy range from 17 keV to 75 keV, have been recorded using a Charged Coupled Device (CCD) in single hit regime and a Dual Crystal Spectrometer (DCS). High-resolution point-projection 2D radiographs have also been recorded on Fuji BaFBr:Eu2 image plates using calibrated resolution grids. We discuss the results in light of the requirements for applications at NIF. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We briefly review currently practiced methods of X-ray phase contrast imaging and consider some of their relative features, especially in regard to applicability to clinical medical studies. Various related technological issues and promising future areas of development are also briefly discussed. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Improving the quality of radiographic images involves several aspects: the X ray source, the device used to obtain the image, the optical array in the process and the image manipulation. We give a brief and general view of these different aspects and new techniques for radiography. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present initial results from experiments performed to characterize plastic capsules using a compact x-pinch pulser with a floor space < 1m2. The pulser produces 80 kA current with a rise time of 40 ns. Various wire materials including tungsten, molybdenum and aluminum were used. X-pinch length was varied to obtain maximum x-ray yield and photon energies. X-rays in 5–9 keV energy range were used for the phase contrast radiography of plastic shells. Results with plastic capsules (1 mm diameter, 20 μm thick wall) show a phase contrast effect at the edges of the wall. The sharpness of the image reveals source size of less than 3 μm. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Several pinch related experiment, their drivers and related diagnostics are being developed in our laboratory. The first set of experiments is to investigate various aspects of magnetized target fusion (MTF/MAGO). To drive the liner, in Z or theta pinch configuration, a 1.2 MJ, 3.6 MA capacitor bank is developed. For liner diagnostics flash radiography, VISAR and pyrometery are being developed. To produce magnetized (target) plasma a 120 kJ, 3 MA and several other banks are developed. Hot magnetized Plasma will be diagnosed by optical schlieren, interferometery and X-Ray spectrometry. A terra-watt system consisting of a Marx bank and water line delivering 800 kA at 1.6 MV will be commissioned, soon. The device will be used to study different pinch (wire array) configurations for production of electro-magnetic radiations. Smaller pulsed power systems, consisting of 1MV/500 kV Marx bank/tesla transformer and than water or solid state (cables) pulse forming network (coax) are also being developed for capillary discharge and other experiments. Two plasma foci experiments are also being conducted. The effort is produce a repetitively operating compact plasma focus. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Backpropagation type artificial neural networks (ANN) were used to estimate the thickness of two overlapping materials by inspecting two X-ray images obtained at different x-ray tube voltage settings. Radiographic images of overlapping aluminum and brass wedges were simulated by using the X-ray radiography simulation program XRSIM. Simulated images were used for training and testing of the ANNs. The average estimation error was less than 4% and 7% on the training and test data respectively. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The technique of Digital Speckle Radiography (DSR) has been shown to be widely applicable to the field of ballistics through its ability to measure internal displacement fields to a high precision. In a DSR experiment, a flat plane, typically 500 μm thick, of X-ray opaque filings are introduced into the sample during manufacture. Flash X-rays can then be used to image the plane, both before and during an impact event, to produce random speckled images on an X-ray film. Small sub-regions of the images can be tracked relative to each other using a Digital Speckle Photography (DSP) correlation algorithm. This produces a displacement field within the specimen on the seeded plane. By repeating an experiment with identical specimens, but varying the delay of the X-ray exposure, a full time history of the impact event can be obtained. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

A variety of new types of digital x-ray detectors are being used in inspection applications. It is often desirable to compare the relative performance of different detectors for a particular problem and choose the one that will produce the best results. We have developed computer simulation models that can be used to assist in this comparison. These models are used in conjunction with the general x-ray inspection simulation code (XRSIM) that was developed previously at CNDE. In this paper we describe a general procedure for determining the parameters needed to model a generic digital detector. We then show the results of applying this procedure to model amorphous silicon and image intensifier/CCD camera systems. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Industrial X-ray radiography is often done using a broad band energy source and always a broad band energy detector. There exist several major advantages in the use of narrow band sources and or detectors, one of which is the separation of scattered radiation from primary radiation. ARDEC has developed a large detector array system in which every detector element acts like a multi-channel analyzer. A radiographic image is created from the number of photons detected in each detector element, rather than from the total energy absorbed in the elements. For high energies, 25 KeV to 4 MeV, used in radiography, energy discriminating detectors have been limited to less than 20,000 photons per second per detector element. This rate is much too slow for practical radiography. Our detector system processes over two million events per second per detector pixel, making radiographic imaging practical. This paper expounds on the advantages of the ARDEC radiographic imaging process. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this work, we introduce a new technique to perform densitometric and multielemental analysis of samples at the same time using a simple detector with heavy ion micro-beams. It consists in the simultaneous analysis of X-rays induced in the sample and in a secondary target arranged behind the specimen. The X-rays originated in the secondary target are attenuated when crossing the specimen producing a radiographic image with a monochromatic source. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Many high-energy sources exhibit variable optical emission which can be analysed over prolonged time intervals with reasonable sampling by means af astronomical archival plates. Few selected examples are shown and discussed. [ABSTRACT FROM AUTHOR]

Biological samples are of great interest for many imaging techniques. The samples usually contain small structures and weak absorption properties. The combinations of weak signals with overlying structures make feature recognition difficult in many cases. In the x-ray regime, a relatively new imaging technique Diffraction Enhanced Imaging (DEI) has superior tissue contrast over conventional radiography and is proven to be very sensitive method. Multiple images taken by DEI are called Multiple Image Radiography (MIR). The purpose of this study is to validate the potential application of the method and to show that MIR-DEI method may give more information about the sample. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We measured coherent x-ray diffraction (CXD), an emerging technique to obtain three-dimensional internal and external images of crystals, on ZSM-5 zeolite microcrystals to get internal density distribution and to map deformation field of strain. The experiments were performed at the beamline 34-ID-C in Advanced Photon Source at Argonne National Laboratory in the US. The CXD patterns of ZSM-5 zeolite microcrystals with sizes of 2 μm by monochromatic coherent x-rays with energy of 9 keV were obtained under continuously surrounding and Bragg conditions as a function of temperature. The oversampled diffraction patterns are inverted to obtain three-dimensional images of the shapes and internal strain fields of zeolite microcrystals using phase retrieval algorithms of error reduction and a hybrid input-output method. The internal density and strain distribution as a function of temperature are discussed. [ABSTRACT FROM AUTHOR]

TLD-100 (thermoluminescent dosimeter) cards (chips) were calibrated using X-rays with energies of 25–250 kV produced by a Cs-137 source. The energy responses of lithium fluoride crystals for different energies of X-rays were studied. QA/QC was then performed in the Albanian Ionizing Radiation Metrology Laboratory. Based on the QA/QC results, the chips were used to study the doses to different organs in diagnostic radiology. Organ dose was evaluated after calculation of e dose in air (Kair), using an ionizing chamber. [ABSTRACT FROM AUTHOR]