[Diffraction gratings used in x-ray spectroscopy]: Final report

International Nuclear Information System (INIS)

Smith, H.I.

1988-01-01

This subcontract was initiated in order to facilitate the development at MIT of technologies for fabricating the very fine diffraction grating required in x-ray spectroscopy at Lawrence Livermore Laboratory (LLL). These gratings are generally gold transmission gratings with spatial periods of 200 nm or less. The major focus of our efforts was to develop a means of fabricating gratings of 100 nm period. We explored two approaches: e-beam fabrication of x-ray lithography masks, and achromatic holographic lithography. This work was pursued by Erik Anderson as a major component of his Ph.D. thesis. Erik was successful in both the e-beam and holographic approaches. However, the e-beam method proved to be highly impractical: exposure times of about 115 days would be required to cover an area of 1 cm 2 . The achromatic holography, on the other hand, should be capable of exposing areas well in excess of 1 cm 2 in times under 1 hour. Moreover, 100 nm-period gratings produced by achromatic holography are coherent over their entire area whereas gratings produced by e-beam lithography are coherent only over areas /approximately/100 μm. The remainder of this report consists of portions excerpted from Erik Anderson's thesis. These contain all the details of our work on 100 nm period gratings. 26 refs., 17 figs

A Soft X-ray Spectrometer using a Highly Dispersive Multilayer Grating

International Nuclear Information System (INIS)

Warwick, Tony; Padmore, Howard; Voronov, Dmitriy; Yashchuk, Valeriy

2010-01-01

There is a need for higher resolution spectrometers as a tool for inelastic x-ray scattering. Currently, resolving power around R = 10,000 is advertised. Measured RIXS spectra are often limited by this instrumental resolution and higher resolution spectrometers using conventional gratings would be prohibitively large. We are engaged in a development program to build blazed multilayer grating structures for diffracting soft x-rays in high order. This leads to spectrometers with dispersion much higher than is possible using metal coated-gratings. The higher dispersion then provides higher resolution and the multilayer gratings are capable of operating away from grazing incidence as required. A spectrometer design is presented with a total length 3.8 m and capable of 10 5 resolving power.

A Soft X-ray Spectrometer using a Highly Dispersive Multilayer Grating

International Nuclear Information System (INIS)

Warwick, Tony; Padmore, Howard; Voronov, Dmitriy; Yashchuk, Valeriy

2010-01-01

There is a need for higher resolution spectrometers as a tool for inelastic x-ray scattering. Currently, resolving power around R = 10,000 is advertised. Measured RIXS spectra are often limited by this instrumental resolution and higher resolution spectrometers using conventional gratings would be prohibitively large. We are engaged in a development program to build blazed multilayer grating structures for diffracting soft x-rays in high order. This leads to spectrometers with dispersion much higher than is possible using metal coated-gratings. The higher dispersion then provides higher resolution and the multilayer gratings are capable of operating away from grazing incidence as required. A spectrometer design is presented with a total length 3.8m and capable of 10 5 resolving power.

Innovative diffraction gratings for high-resolution resonant inelastic soft x-ray scattering spectroscopy

International Nuclear Information System (INIS)

Voronov, D.L.; Warwick, T.; Gullikson, E. M.; Salmassi, F.; Padmore, H. A.

2016-01-01

High-resolution Resonant Inelastic X-ray Scattering (RIXS) requires diffraction gratings with very exacting characteristics. The gratings should provide both very high dispersion and high efficiency which are conflicting requirements and extremely challenging to satisfy in the soft x-ray region for a traditional grazing incidence geometry. To achieve high dispersion one should increase the groove density of a grating; this however results in a diffraction angle beyond the critical angle range and results in drastic efficiency loss. The problem can be solved by use of multilayer coated blazed gratings (MBG). In this work we have investigated the diffraction characteristics of MBGs via numerical simulations and have developed a procedure for optimization of grating design for a multiplexed high resolution imaging spectrometer for RIXS spectroscopy to be built in sector 6 at the Advanced Light Source (ALS). We found that highest diffraction efficiency can be achieved for gratings optimized for 4"t"h or 5"t"h order operation. Fabrication of such gratings is an extremely challenging technological problem. We present a first experimental prototype of these gratings and report its performance. High order and high line density gratings have the potential to be a revolutionary new optical element that should have great impact in the area of soft x-ray RIXS.

Hard-x-ray phase-imaging microscopy using the self-imaging phenomenon of a transmission grating

International Nuclear Information System (INIS)

Yashiro, Wataru; Harasse, Sebastien; Momose, Atsushi; Takeuchi, Akihisa; Suzuki, Yoshio

2010-01-01

We report on a hard-x-ray imaging microscope consisting of a lens, a sample, and a transmission grating. After the theoretical framework of self-imaging phenomenon by the grating in the system is presented, equations for the electric field on the image plane are derived for ideal and real lenses and an equation for the intensity on the image plane for partially coherent illumination is derived. The equations are simple and similar to those applying to a projection microscope consisting of a transmission grating except that there is no defocusing effect, regardless of whether the grating is in front of or behind the lens. This means that x-ray phase-imaging microscopy can be done without the defocusing effect. It is also shown that, by resolving the self-image on the image plane, high-sensitive x-ray phase-imaging microscopy can be attained without degradation in the spatial resolution due to diffraction by the grating. Experimental results obtained using partially coherent illumination from a synchrotron x-ray source confirm that hard-x-ray phase-imaging microscopy can be quantitatively performed with high sensitivity and without the spatial resolution degradation.

Trochoidal X-ray Vector Radiography: Directional dark-field without grating stepping

Science.gov (United States)

Sharma, Y.; Bachche, S.; Kageyama, M.; Kuribayashi, M.; Pfeiffer, F.; Lasser, T.; Momose, A.

2018-03-01

X-ray Vector Radiography (XVR) is an imaging technique that reveals the orientations of sub-pixel sized structures within a sample. Several dark-field radiographs are acquired by rotating the sample around the beam propagation direction and stepping one of the gratings to several positions for every pose of the sample in an X-ray grating interferometry setup. In this letter, we present a method of performing XVR of a continuously moving sample without the need of any grating motion. We reconstruct the orientations within a sample by analyzing the change in the background moire fringes caused by the sample moving and simultaneously rotating in plane (trochoidal trajectory) across the detector field-of-view. Avoiding the motion of gratings provides significant advantages in terms of stability and repeatability, while the continuous motion of the sample makes this kind of system adaptable for industrial applications such as the scanning of samples on a conveyor belt. Being the first step in the direction of utilizing advanced sample trajectories to replace grating motion, this work also lays the foundations for a full three dimensional reconstruction of scattering function without grating motion.

Characterization of diffraction gratings by use of a tabletop soft-x-ray laser

International Nuclear Information System (INIS)

Seminario, Max; Rocca, Jorge J.; Depine, Ricardo A.; Bach, Benny; Bach, Bernie

2001-01-01

We have demonstrated the use of a high-repetition-rate 46.9-mm tabletop laser to characterize diffraction gratings designed for grazing-incidence operation in the soft-x-ray spectral region. The efficiencies for various diffraction orders were measured as a function of angle of incidence and compared with the results of model simulations. This measurement technique provides benchmarks with which to improve electromagnetic codes used in the design of soft-x-ray diffraction gratings. The results illustrate the potential of compact tabletop soft-x-ray lasers for use as a new tool for characterization of short-wavelength optics at the manufacturer's site

Integrated X-ray testing of the electro-optical breadboard model for the XMM reflection grating spectrometer

Energy Technology Data Exchange (ETDEWEB)

Bixler, J.V.; Craig, W.; Decker, T. [Lawrence Livermore National Lab., CA (United States); Aarts, H.; Boggende, T. den; Brinkman, A.C. [Space Research Organization Netherlands, Utrecht (Netherlands); Burkert, W.; Brauninger, H. [Max-Planck Institute fur Extraterrestische Physik, Testanlage (Germany); Branduardi-Raymont, G. [Univ. College London (United Kingdom); Dubbeldam, L. [Space Research Organization Netherlands, Leiden (Netherlands)] [and others

1994-07-12

X-ray calibration of the Electro-Optical Breadboard Model (EOBB) of the XXM Reflection Grating Spectrometer has been carried out at the Panter test facility in Germany. The EOBB prototype optics consisted of a four-shell grazing incidence mirror module followed by an array of eight reflection gratings. The dispersed x-rays were detected by an array of three CCDs. Line profile and efficiency measurements where made at several energies, orders, and geometric configurations for individual gratings and for the grating array as a whole. The x-ray measurements verified that the grating mounting method would meet the stringent tolerances necessary for the flight instrument. Post EOBB metrology of the individual gratings and their mountings confirmed the precision of the grating boxes fabrication. Examination of the individual grating surface`s at micron resolution revealed the cause of anomalously wide line profiles to be scattering due to the crazing of the replica`s surface.

The recent development of an X-ray grating interferometer at Shanghai Synchrotron Radiation Facility

Energy Technology Data Exchange (ETDEWEB)

Sun Haohua; Kou Bingquan; Xi Yan; Qi Juncheng; Sun Jianqi; Mohr, Juergen; Boerner, Martin; Zhao Jun; Xu, Lisa X.; Xiao Tiqiao; Wang Yujie [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China) and Med-X Research Institute, Shanghai Jiao Tong University, Shanghai 200040 (China); Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Karlsruhe Institute of Technology (KIT), Institute for Microstructure Technology (IMT), Hermannvon-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2012-07-31

An X-ray grating interferometer has been installed at Shanghai Synchrotron Radiation Facility (SSRF). Three sets of phase gratings were designed to cover the wide X-ray energy range needed for biological and soft material imaging capabilities. The performance of the grating interferometer has been evaluated by a tomography study of a PMMA particle packing and a new born mouse chest. In the mouse chest study, the carotid artery and carotid vein inside the mouse can be identified in situ without contrast agents.

The recent development of an X-ray grating interferometer at Shanghai Synchrotron Radiation Facility

International Nuclear Information System (INIS)

Sun Haohua; Kou Bingquan; Xi Yan; Qi Juncheng; Sun Jianqi; Mohr, Jürgen; Börner, Martin; Zhao Jun; Xu, Lisa X.; Xiao Tiqiao; Wang Yujie

2012-01-01

An X-ray grating interferometer has been installed at Shanghai Synchrotron Radiation Facility (SSRF). Three sets of phase gratings were designed to cover the wide X-ray energy range needed for biological and soft material imaging capabilities. The performance of the grating interferometer has been evaluated by a tomography study of a PMMA particle packing and a new born mouse chest. In the mouse chest study, the carotid artery and carotid vein inside the mouse can be identified in situ without contrast agents.

Revisiting Bragg's X-ray microscope: Scatter based optical transient grating detection of pulsed ionising radiation

International Nuclear Information System (INIS)

Fullagar, Wilfred K.; Paganin, David M.; Hall, Chris J.

2011-01-01

Transient optical gratings for detecting ultrafast signals are routine for temporally resolved photochemical investigations. Many processes can contribute to the formation of such gratings; we indicate use of optically scattering centres that can be formed with highly variable latencies in different materials and devices using ionising radiation. Coherent light scattered by these centres can form the short-wavelength-to-optical-wavelength, incoherent-to-coherent basis of a Bragg X-ray microscope, with inherent scope for optical phasing. Depending on the dynamics of the medium chosen, the way is open to both ultrafast pulsed and integrating measurements. For experiments employing brief pulses, we discuss high-dynamic-range short-wavelength diffraction measurements with real-time optical reconstructions. Applications to optical real-time X-ray phase-retrieval are considered. -- Research highlights: → It is timely that the concept of Bragg's X-ray microscope be revisited. → Transient gratings can be used for X-ray all-optical information processing. → Applications to optical real-time X-ray phase-retrieval are considered.

X-ray phase radiography and tomography with grating interferometry and the reverse projection technique

International Nuclear Information System (INIS)

Wang, Zhili; Gao, Kun; Ge, Xin; Wu, Zhao; Chen, Heng; Wang, Shenghao; Wu, Ziyu; Zhu, Peiping; Yuan, Qingxi; Huang, Wanxia; Zhang, Kai

2013-01-01

X-ray grating interferometry provides substantially increased contrast over conventional absorption-based imaging methods, and therefore new and complementary information. Compared with other phase-contrast imaging techniques, x-ray grating interferometry can overcome some of the problems that have impaired the applications of x-ray phase-contrast radiography and phase tomography. Recently, special attention has been paid to the development of quantitative phase retrieval methods, which is mandatory to perform x-ray phase tomography, to achieve material identification, to differentiate distinct tissues, etc. Typically, the phase-stepping approach has been utilized for phase retrieval in grating interferometry. This method requires a grating scanning and acquisition of multiple radiographic projections, and therefore is disadvantageous in terms of imaging speed and radiation damage. Here we present an innovative, highly sensitive approach, dubbed ‘reverse projection’ (RP), for quantitative phase retrieval. Compared with the phase-stepping approach, the present RP method abandons grating scanning completely, and thus is advantageous due to its much higher efficiency and the reduced radiation dose, without the degradation of reconstruction quality. This review presents a detailed explanation of the principle of the RP method. Both radiography and phase tomography experiments are performed to validate the RP method. We believe that this new technique will find widespread applications in biomedical imaging and in vivo studies. (paper)

Contextual Multivariate Segmentation of Pork Tissue from Grating-Based Multimodal X-Ray Tomography

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Nielsen, Mikkel S.; Ersbøll, Bjarne Kjær

2013-01-01

have made novel X-ray image modalities available, where the refraction and scattering of X-rays is obtained simultaneously with the absorption properties, providing enhanced contrast for soft biological tissues. This paper demonstrates how data obtained from grating-based imaging can be segmented...

Design and fabrication of an active polynomial grating for soft-X-ray monochromators and spectrometers

CERN Document Server

Chen, S J; Perng, S Y; Kuan, C K; Tseng, T C; Wang, D J

2001-01-01

An active polynomial grating has been designed for use in synchrotron radiation soft-X-ray monochromators and spectrometers. The grating can be dynamically adjusted to obtain the third-order-polynomial surface needed to eliminate the defocus and coma aberrations at any photon energy. Ray-tracing results confirm that a monochromator or spectrometer based on this active grating has nearly no aberration limit to the overall spectral resolution in the entire soft-X-ray region. The grating substrate is made of a precisely milled 17-4 PH stainless steel parallel plate, which is joined to a flexure-hinge bender shaped by wire electrical discharge machining. The substrate is grounded into a concave cylindrical shape with a nominal radius and then polished to achieve a roughness of 0.45 nm and a slope error of 1.2 mu rad rms. The long trace profiler measurements show that the active grating can reach the desired third-order polynomial with a high degree of figure accuracy.

A soft X-Ray flat field grating spectrograph and its experimental applications

International Nuclear Information System (INIS)

Ni Yuanlong; Mao Chusheng

2001-01-01

The principle, structure, and application results of a flat field grating spectrograph for X-ray laser research is presented. There are two kinds of the spectrograph. One uses a varied space grating with nominal line spacing 1200 l/mm, the spectral detection range is 5 - 50 nm, and another uses a 2400 l/mm varied line space grating, detection range is 1 - 10 nm. The experimental results of the former is introduced only. Both experimental results of this instrument using the soft X-ray film and a streak camera as the detecting elements are given. The spectral resolutions are 0.01 nm and 0.05 nm, respectively. The temporal resolution is 30 ps. Finally, the stigmatic structure of the spectrograph is introduced, which uses cylindrical mirror and spherical mirror as a focusing system. The magnification is 5, spatial resolution is 25 μm. The experimental results are given as well

Grating-based X-ray tomography of 3D food structures

DEFF Research Database (Denmark)

Miklos, Rikke; Nielsen, Mikkel Schou; Einarsdottir, Hildur

2016-01-01

A novel grating based X-ray phase-contrast tomographic method has been used to study how partly substitution of meat proteins with two different types of soy proteins affect the structure of the formed protein gel in meat emulsions. The measurements were performed at the Swiss synchrotron radiati...

X-ray phase microtomography with a single grating for high-throughput investigations of biological tissue.

Science.gov (United States)

Zdora, Marie-Christine; Vila-Comamala, Joan; Schulz, Georg; Khimchenko, Anna; Hipp, Alexander; Cook, Andrew C; Dilg, Daniel; David, Christian; Grünzweig, Christian; Rau, Christoph; Thibault, Pierre; Zanette, Irene

2017-02-01

The high-throughput 3D visualisation of biological specimens is essential for studying diseases and developmental disorders. It requires imaging methods that deliver high-contrast, high-resolution volumetric information at short sample preparation and acquisition times. Here we show that X-ray phase-contrast tomography using a single grating can provide a powerful alternative to commonly employed techniques, such as high-resolution episcopic microscopy (HREM). We present the phase tomography of a mouse embryo in paraffin obtained with an X-ray single-grating interferometer at I13-2 Beamline at Diamond Light Source and discuss the results in comparison with HREM measurements. The excellent contrast and quantitative density information achieved non-destructively and without staining using a simple, robust setup make X-ray single-grating interferometry an optimum candidate for high-throughput imaging of biological specimens as an alternative for existing methods like HREM.

High-energy x-ray grating-based phase-contrast radiography of human anatomy

Science.gov (United States)

Horn, Florian; Hauke, Christian; Lachner, Sebastian; Ludwig, Veronika; Pelzer, Georg; Rieger, Jens; Schuster, Max; Seifert, Maria; Wandner, Johannes; Wolf, Andreas; Michel, Thilo; Anton, Gisela

2016-03-01

X-ray grating-based phase-contrast Talbot-Lau interferometry is a promising imaging technology that has the potential to raise soft tissue contrast in comparison to conventional attenuation-based imaging. Additionally, it is sensitive to attenuation, refraction and scattering of the radiation and thus provides complementary and otherwise inaccessible information due to the dark-field image, which shows the sub-pixel size granularity of the measured object. Until recent progress the method has been mainly limited to photon energies below 40 keV. Scaling the method to photon energies that are sufficient to pass large and spacious objects represents a challenging task. This is caused by increasing demands regarding the fabrication process of the gratings and the broad spectra that come along with the use of polychromatic X-ray sources operated at high acceleration voltages. We designed a setup that is capable to reach high visibilities in the range from 50 to 120 kV. Therefore, spacious and dense parts of the human body with high attenuation can be measured, such as a human knee. The authors will show investigations on the resulting attenuation, differential phase-contrast and dark-field images. The images experimentally show that X-ray grating-based phase-contrast radiography is feasible with highly absorbing parts of the human body containing massive bones.

Grating Oriented Line-Wise Filtration (GOLF) for Dual-Energy X-ray CT

Science.gov (United States)

Xi, Yan; Cong, Wenxiang; Harrison, Daniel; Wang, Ge

2017-12-01

In medical X-ray Computed Tomography (CT), the use of two distinct X-ray source spectra (energies) allows dose-reduction and material discrimination relative to that achieved with only one source spectrum. Existing dual-energy CT methods include source kVp-switching, double-layer detection, dual-source gantry, and two-pass scanning. Each method suffers either from strong spectral correlation or patient-motion artifacts. To simultaneously address these problems, we propose to improve CT data acquisition with the Grating Oriented Line-wise Filtration (GOLF) method, a novel X-ray filter that is placed between the source and patient. GOLF uses a combination of absorption and filtering gratings that are moved relative to each other and in synchronization with the X-ray tube kVp-switching process and/or the detector view-sampling process. Simulation results show that GOLF can improve the spectral performance of kVp-switching to match that of dual-source CT while avoiding patient motion artifacts and dual imaging chains. Although significant flux is absorbed by this pre-patient filter, the proposed GOLF method is a novel path for cost-effectively extracting dual-energy or multi-energy data and reducing radiation dose with or without kVp switching.

Development and Characterization of Two-Dimensional Gratings for Single-Shot X-ray Phase-Contrast Imaging

Directory of Open Access Journals (Sweden)

Margarita Zakharova

2018-03-01

Full Text Available Single-shot grating-based phase-contrast imaging techniques offer additional contrast modalities based on the refraction and scattering of X-rays in a robust and versatile configuration. The utilization of a single optical element is possible in such methods, allowing the shortening of the acquisition time and increasing flux efficiency. One of the ways to upgrade single-shot imaging techniques is to utilize customized optical components, such as two-dimensional (2D X-ray gratings. In this contribution, we present the achievements in the development of 2D gratings with UV lithography and gold electroplating. Absorption gratings represented by periodic free-standing gold pillars with lateral structure sizes from 5 µm to 25 µm and heights from 5 µm to 28 µm have shown a high degree of periodicity and defect-free patterns. Grating performance was tested in a radiographic setup using a self-developed quality assessment algorithm based on the intensity distribution histograms. The algorithm allows the final user to estimate the suitability of a specific grating to be used in a particular setup.

Imaging properties of high aspect ratio absorption gratings for use in preclinical x-ray grating interferometry.

Science.gov (United States)

Trimborn, Barbara; Meyer, Pascal; Kunka, Danays; Zuber, Marcus; Albrecht, Frederic; Kreuer, Sascha; Volk, Thomas; Baumbach, Tilo; Koenig, Thomas

2016-01-21

X-ray grating interferometry is one among various methods that allow extracting the so-called phase and visibility contrasts in addition to the well-known transmission images. Crucial to achieving a high image quality are the absorption gratings employed. Here, we present an in-depth analysis of how the grating type and lamella heights influence the final images. Benchmarking gratings of two different designs, we show that a frequently used proxy for image quality, a grating's so-called visibility, is insufficient to predict contrast-to-noise ratios (CNRs). Presenting scans from an excised rat lung, we demonstrate that the CNRs obtained for transmission and visibility images anti-correlate. This is explained by the stronger attenuation implied by gratings that are engineered to provide high visibilities by means of an increased lamella height. We show that even the visibility contrast can suffer from this effect when the associated reduced photon flux on the detector is not outweighed by a corresponding gain in visibility. Resulting in an inevitable trade-off between the quality of the two contrasts, the question of how an optimal grating should be designed can hence only be answered in terms of Pareto optimality.

Analytic theory of soft x-ray diffraction by lamellar multilayer gratings

NARCIS (Netherlands)

Kozhevnikov, I.V.; van der Meer, R.; Bastiaens, Hubertus M.J.; Boller, Klaus J.; Bijkerk, Frederik

2011-01-01

An analytic theory describing soft x-ray diffraction by Lamellar Multilayer Gratings (LMG) has been developed. The theory is derived from a coupled waves approach for LMGs operating in the single-order regime, where an incident plane wave can only excite a single diffraction order. The results from

A user-friendly LabVIEW software platform for grating based X-ray phase-contrast imaging.

Science.gov (United States)

Wang, Shenghao; Han, Huajie; Gao, Kun; Wang, Zhili; Zhang, Can; Yang, Meng; Wu, Zhao; Wu, Ziyu

2015-01-01

X-ray phase-contrast imaging can provide greatly improved contrast over conventional absorption-based imaging for weakly absorbing samples, such as biological soft tissues and fibre composites. In this study, we introduced an easy and fast way to develop a user-friendly software platform dedicated to the new grating-based X-ray phase-contrast imaging setup at the National Synchrotron Radiation Laboratory of the University of Science and Technology of China. The control of 21 motorized stages, of a piezoelectric stage and of an X-ray tube are achieved with this software, it also covers image acquisition with a flat panel detector for automatic phase stepping scan. Moreover, a data post-processing module for signals retrieval and other custom features are in principle available. With a seamless integration of all the necessary functions in one software package, this platform greatly facilitate users' activities during experimental runs with this grating based X-ray phase contrast imaging setup.

Quantitative Analysis of Micro-Structure in Meat Emulsions from Grating-Based Multimodal X-Ray Tomography

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Nielsen, Mikkel Schou; Miklos, Rikke

2013-01-01

Using novel X-ray techniques, based on grating-interferometry, new imaging modalities can be obtained simultaneously with absorption computed tomography (CT). These modalities, called phase contrast and dark field imaging, measure the electron density and the diffusion length of the sample....... Enhanced contrast capabilities of this X-ray technique makes studies on materials with similar attenuation properties possible. In this paper the focus is set on processing grating-based X-ray tomograms of meat emulsions to quantitatively measure micro-structural changes due to heat treatment. The emulsion...... samples were imaged both in a raw and cooked state. Additionally, different fat types were used in the emulsions in order to compare micro-structural differences when either pork fat or sunflower oil was used. From the reconstructed tomograms the different ingredients in the emulsions were segmented using...

Large-area full field x-ray differential phase-contrast imaging using 2D tiled gratings

Science.gov (United States)

Schröter, Tobias J.; Koch, Frieder J.; Kunka, Danays; Meyer, Pascal; Tietze, Sabrina; Engelhardt, Sabine; Zuber, Marcus; Baumbach, Tilo; Willer, Konstantin; Birnbacher, Lorenz; Prade, Friedrich; Pfeiffer, Franz; Reichert, Klaus-Martin; Hofmann, Andreas; Mohr, Jürgen

2017-06-01

Grating-based x-ray differential phase-contrast imaging (DPCI) is capable of acquiring information based on phase-shift and dark-field signal, in addition to conventional x-ray absorption-contrast. Thus DPCI gives an advantage to investigate composite materials with component wise similar absorption properties like soft tissues. Due to technological challenges in fabricating high quality gratings over a large extent, the field of view (FoV) of the imaging systems is limited to a grating area of a couple of square centimeters. For many imaging applications (e.g. in medicine), however, a FoV that ranges over several ten centimeters is needed. In this manuscript we propose to create large area gratings of theoretically any extent by assembling a number of individual grating tiles. We discuss the precision needed for alignment of each microstructure tile in order to reduce image artifacts and to preserve minimum 90% of the sensitivity obtainable with a monolithic grating. To achieve a reliable high precision alignment a semiautomatic assembly system consisting of a laser autocollimator, a digital microscope and a force sensor together with positioning devices was built. The setup was used to tile a first four times four analyzer grating with a size of 200 mm  ×  200 mm together with a two times two phase grating. First imaging results prove the applicability and quality of the tiling concept.

A new method for information retrieval in two-dimensional grating-based X-ray phase contrast imaging

International Nuclear Information System (INIS)

Wang Zhi-Li; Gao Kun; Chen Jian; Ge Xin; Tian Yang-Chao; Wu Zi-Yu; Zhu Pei-Ping

2012-01-01

Grating-based X-ray phase contrast imaging has been demonstrated to be an extremely powerful phase-sensitive imaging technique. By using two-dimensional (2D) gratings, the observable contrast is extended to two refraction directions. Recently, we have developed a novel reverse-projection (RP) method, which is capable of retrieving the object information efficiently with one-dimensional (1D) grating-based phase contrast imaging. In this contribution, we present its extension to the 2D grating-based X-ray phase contrast imaging, named the two-dimensional reverse-projection (2D-RP) method, for information retrieval. The method takes into account the nonlinear contributions of two refraction directions and allows the retrieval of the absorption, the horizontal and the vertical refraction images. The obtained information can be used for the reconstruction of the three-dimensional phase gradient field, and for an improved phase map retrieval and reconstruction. Numerical experiments are carried out, and the results confirm the validity of the 2D-RP method

Hard synchrotron radiation scattering from a nonideal surface grating from multilayer X-ray mirrors

International Nuclear Information System (INIS)

Punegov, V.I.; Nesterets, Ya.I.; Mytnichenko, S.V.; Kovalenko, N.V.; Chernov, V.A.

2003-01-01

The hard synchrotron radiation scattering from a multilayer surface grating is theoretically and experimentally investigated. The numerical calculations of angular distribution of scattering intensity from X-ray mirror Ni/C are executed with use of recurrence formulae and statistical dynamical theory of diffraction. It is shown, that the essential role in formation of a diffraction pattern plays a diffuse scattering caused by structure imperfection of a multilayer grating [ru

Low-dose multiple-information retrieval algorithm for X-ray grating-based imaging

International Nuclear Information System (INIS)

Wang Zhentian; Huang Zhifeng; Chen Zhiqiang; Zhang Li; Jiang Xiaolei; Kang Kejun; Yin Hongxia; Wang Zhenchang; Stampanoni, Marco

2011-01-01

The present work proposes a low dose information retrieval algorithm for X-ray grating-based multiple-information imaging (GB-MII) method, which can retrieve the attenuation, refraction and scattering information of samples by only three images. This algorithm aims at reducing the exposure time and the doses delivered to the sample. The multiple-information retrieval problem in GB-MII is solved by transforming a nonlinear equations set to a linear equations and adopting the nature of the trigonometric functions. The proposed algorithm is validated by experiments both on conventional X-ray source and synchrotron X-ray source, and compared with the traditional multiple-image-based retrieval algorithm. The experimental results show that our algorithm is comparable with the traditional retrieval algorithm and especially suitable for high Signal-to-Noise system.

Investigation on the properties of a laminar grating as a soft x-ray beam splitter

International Nuclear Information System (INIS)

Liu Ying; Fuchs, Hans-Joerg; Liu Zhengkun; Chen Huoyao; He Shengnan; Fu Shaojun; Kley, Ernst-Bernhard; Tuennermann, Andreas

2010-01-01

Laminar-type gratings as soft x-ray beam splitters for interferometry are presented. Gold-coated grating beam splitters with 1000 lines/mm are designed for grazing incidence operation at 13.9nm. They are routinely fabricated using electron beam lithography and ion etching techniques. The laminar grating is measured to have almost equal absolute efficiencies of about 20% in the zeroth and -1st orders, which enables a fringe visibility up to 0.99 in the interferometer. The discrepancy of the grating profiles between the optimized theoretical and the experimental results is analyzed according to the comparison of the optimized simulation results and the measurement realization of the grating efficiencies. By a precise control of the grating profile, the grating efficiency in the -1st order and the fringe visibility could be improved to 25% and 1, respectively.

Revisiting Bragg's X-ray microscope: scatter based optical transient grating detection of pulsed ionising radiation.

Science.gov (United States)

Fullagar, Wilfred K; Paganin, David M; Hall, Chris J

2011-06-01

Transient optical gratings for detecting ultrafast signals are routine for temporally resolved photochemical investigations. Many processes can contribute to the formation of such gratings; we indicate use of optically scattering centres that can be formed with highly variable latencies in different materials and devices using ionising radiation. Coherent light scattered by these centres can form the short-wavelength-to-optical-wavelength, incoherent-to-coherent basis of a Bragg X-ray microscope, with inherent scope for optical phasing. Depending on the dynamics of the medium chosen, the way is open to both ultrafast pulsed and integrating measurements. For experiments employing brief pulses, we discuss high-dynamic-range short-wavelength diffraction measurements with real-time optical reconstructions. Applications to optical real-time X-ray phase-retrieval are considered. Copyright © 2010 Elsevier B.V. All rights reserved.

Diagnosing and mapping pulmonary emphysema on X-ray projection images: incremental value of grating-based X-ray dark-field imaging.

Science.gov (United States)

Meinel, Felix G; Schwab, Felix; Schleede, Simone; Bech, Martin; Herzen, Julia; Achterhold, Klaus; Auweter, Sigrid; Bamberg, Fabian; Yildirim, Ali Ö; Bohla, Alexander; Eickelberg, Oliver; Loewen, Rod; Gifford, Martin; Ruth, Ronald; Reiser, Maximilian F; Pfeiffer, Franz; Nikolaou, Konstantin

2013-01-01

To assess whether grating-based X-ray dark-field imaging can increase the sensitivity of X-ray projection images in the diagnosis of pulmonary emphysema and allow for a more accurate assessment of emphysema distribution. Lungs from three mice with pulmonary emphysema and three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Median signal intensities of transmission (T), dark-field (V) and a combined parameter (normalized scatter) were compared between emphysema and control group. To determine the diagnostic value of each parameter in differentiating between healthy and emphysematous lung tissue, a receiver-operating-characteristic (ROC) curve analysis was performed both on a per-pixel and a per-individual basis. Parametric maps of emphysema distribution were generated using transmission, dark-field and normalized scatter signal and correlated with histopathology. Transmission values relative to water were higher for emphysematous lungs than for control lungs (1.11 vs. 1.06, pemphysema provides color-coded parametric maps, which show the best correlation with histopathology. In a murine model, the complementary information provided by X-ray transmission and dark-field images adds incremental diagnostic value in detecting pulmonary emphysema and visualizing its regional distribution as compared to conventional X-ray projections.

Grating-based x-ray differential phase contrast imaging with twin peaks in phase-stepping curves—phase retrieval and dewrapping

Energy Technology Data Exchange (ETDEWEB)

Yang, Yi; Xie, Huiqiao; Tang, Xiangyang, E-mail: xiangyang.tang@emory.edu [Imaging and Medical Physics, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1701 Uppergate Dr., C-5018, Atlanta, Georgia 30322 (United States); Cai, Weixing [Department of Radiation Oncology, Brigham and Women’s Hospital Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115 (United States); Mao, Hui [Laboratory of Functional and Molecular Imaging and Nanomedicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1841 Clifton Road NE, Atlanta, Georgia 30329 (United States)

2016-06-15

Purpose: X-ray differential phase contrast CT implemented with Talbot interferometry employs phase-stepping to extract information of x-ray attenuation, phase shift, and small-angle scattering. Since inaccuracy may exist in the absorption grating G{sub 2} due to an imperfect fabrication, the effective period of G{sub 2} can be as large as twice the nominal period, leading to a phenomenon of twin peaks that differ remarkably in their heights. In this work, the authors investigate how to retrieve and dewrap the phase signal from the phase-stepping curve (PSC) with the feature of twin peaks for x-ray phase contrast imaging. Methods: Based on the paraxial Fresnel–Kirchhoff theory, the analytical formulae to characterize the phenomenon of twin peaks in the PSC are derived. Then an approach to dewrap the retrieved phase signal by jointly using the phases of the first- and second-order Fourier components is proposed. Through an experimental investigation using a prototype x-ray phase contrast imaging system implemented with Talbot interferometry, the authors evaluate and verify the derived analytic formulae and the proposed approach for phase retrieval and dewrapping. Results: According to theoretical analysis, the twin-peak phenomenon in PSC is a consequence of combined effects, including the inaccuracy in absorption grating G{sub 2}, mismatch between phase grating and x-ray source spectrum, and finite size of x-ray tube’s focal spot. The proposed approach is experimentally evaluated by scanning a phantom consisting of organic materials and a lab mouse. The preliminary data show that compared to scanning G{sub 2} over only one single nominal period and correcting the measured phase signal with an intuitive phase dewrapping method that is being used in the field, stepping G{sub 2} over twice its nominal period and dewrapping the measured phase signal with the proposed approach can significantly improve the quality of x-ray differential phase contrast imaging in both

Effectiveness of X-ray grating interferometry for non-destructive inspection of packaged devices

Science.gov (United States)

Uehara, Masato; Yashiro, Wataru; Momose, Atsushi

2013-10-01

It is difficult to inspect packaged devices such as IC packages and power modules because the devices contain various components, such as semiconductors, metals, ceramics, and resin. In this paper, we demonstrated the effectiveness of X-ray grating interferometry (XGI) using a laboratory X-ray tube for the industrial inspection of packaged devices. The obtained conventional absorption image showed heavy-elemental components such as metal wires and electrodes, but the image did not reveal the defects in the light-elemental components. On the other hand, the differential phase-contrast image obtained by XGI revealed microvoids and scars in the encapsulant of the samples. The visibility contrast image also obtained by XGI showed some cracks in the ceramic insulator of power module sample. In addition, the image showed the silicon plate surrounded by the encapsulant having the same X-ray absorption coefficient. While these defects and components are invisible in the conventional industrial X-ray imaging, XGI thus has an attractive potential for the industrial inspection of the packaged devices.

High efficiency multilayer blazed gratings for EUV and soft X-rays: Recent developments

International Nuclear Information System (INIS)

Voronov, Dmitriy; Ahn, Minseung; Anderson, Erik; Cambie, Rossana; Chang, Chih-Hao; Goray, Leonid; Gullikson, Eric; Heilmann, Ralf; Salmassi, Farhad; Schattenburg, Mark; Warwick, Tony; Yashchuk, Valeriy; Padmore, Howard

2011-01-01

Multilayer coated blazed gratings with high groove density are the best candidates for use in high resolution EUV and soft x-ray spectroscopy. Theoretical analysis shows that such a grating can be potentially optimized for high dispersion and spectral resolution in a desired high diffraction order without significant loss of diffraction efficiency. In order to realize this potential, the grating fabrication process should provide a perfect triangular groove profile and an extremely smooth surface of the blazed facets. Here we report on recent progress achieved at the Advanced Light Source (ALS) in fabrication of high quality multilayer coated blazed gratings. The blazed gratings were fabricated using scanning beam interference lithography followed by wet anisotropic etching of silicon. A 200 nm period grating coated with a Mo/Si multilayer composed with 30 bi-layers demonstrated an absolute efficiency of 37.6percent in the 3rd diffraction order at 13.6 nm wavelength. The groove profile of the grating was thoroughly characterized with atomic force microscopy before and after the multilayer deposition. The obtained metrology data were used for simulation of the grating efficiency with the vector electromagnetic PCGrate-6.1 code. The simulations showed that smoothing of the grating profile during the multilayer deposition is the main reason for efficiency losses compared to the theoretical maximum. Investigation of the grating with cross-sectional transmission electron microscopy revealed a complex evolution of the groove profile in the course of the multilayer deposition. Impact of the shadowing and smoothing processes on growth of the multilayer on the surface of the sawtooth substrate is discussed.

Optimization of planar metallic nonrefracting transmission-grating profiles for M/sup th/-order intensity maximization in the soft x-ray range

International Nuclear Information System (INIS)

Tatchyn, R.; Csonka, P.L.; Lindau, I.

1982-01-01

In this paper, we derive the thickness profiles of metallic transmission-grating bars which maximize either the power throughput into the m/sup th/ diffracted order or the ratio of the m/sup th/-order diffracted power to the total output power (in the soft x-ray range). The derivation is performed for both general and symmetric bar shapes and for the two physically important cases of continuous gratings and gratings with integral bars. The solutions derived are shown to be valid for cases where the optical constants are generalized to be functions of position in a direction perpendicular to the grating bars. Examples of some optimum profiles for gold in the soft x-ray range are computed on the basis of the presented analysis and tabulated for convenient reference. 18 references

X-ray grating observations of recurrent nova T Pyxidis during the 2011 outburst

Energy Technology Data Exchange (ETDEWEB)

Tofflemire, Benjamin M.; Orio, Marina [Astronomy Department, University of Wisconsin-Madison, 475 N. Charter St., WI 53711 (United States); Page, Kim L.; Osborne, Julian P. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Ciroi, Stefano; Cracco, Valentina; Di Mille, Francesco [Department of Physics and Astronomy, Padova University, Vicolo dell' Osservatorio 3, I-35122 Padova (Italy); Maxwell, Michael [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom)

2013-12-10

The recurrent nova T Pyx was observed with the X-ray gratings of Chandra and XMM-Newton, 210 and 235 days, respectively, after the discovery of the 2011 April 14 outburst. The X-ray spectra show prominent emission lines of C, N, and O, with broadening corresponding to an FWHM of ∼2000-3000 km s{sup –1}, and line ratios consistent with high-density plasma in collisional ionization equilibrium. On day 210 we also measured soft X-ray continuum emission that appears to be consistent with a white dwarf (WD) atmosphere at a temperature ∼420,000 K, partially obscured by anisotropic, optically thick ejecta. The X-ray continuum emission is modulated with the photometric and spectroscopic period observed in quiescence. The continuum at day 235 indicated a WD atmosphere at a consistent effective temperature of 25 days earlier, but with a lower flux. The effective temperature indicates a mass of ∼1 M {sub ☉}. The conclusion of partial WD obscuration is supported by the complex geometry of non-spherically symmetric ejecta confirmed in recent optical spectra obtained with the Southern African Large Telescope in November and December of 2012. These spectra exhibited prominent [O III] nebular lines with velocity structures typical of bipolar ejecta.

Grating monochromator for soft X-ray self-seeding the European XFEL

Energy Technology Data Exchange (ETDEWEB)

Serkez, Svitozar; Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany)

2013-02-15

Self-seeding is a promising approach to significantly narrow the SASE bandwidth of XFELs to produce nearly transform-limited pulses. The implementation of this method in the soft X-ray wavelength range necessarily involves gratings as dispersive elements. We study a very compact self-seeding scheme with a grating monochromator originally designed at SLAC, which can be straightforwardly installed in the SASE3 type undulator beamline at the European XFEL. The monochromator design is based on a toroidal VLS grating working at a fixed incidence angle mounting without entrance slit. It covers the spectral range from 300 eV to 1000 eV. The optical system was studied using wave optics method (in comparison with ray tracing) to evaluate the performance of the self-seeding scheme. Our wave optics analysis takes into account the actual beam wavefront of the radiation from the coherent FEL source, third order aberrations, and errors from each optical element. Wave optics is the only method available, in combination with FEL simulations, for the design of a self-seeding monochromator without exit slit. We show that, without exit slit, the self-seeding scheme is distinguished by the much needed experimental simplicity, and can practically give the same resolving power (about 7000) as with an exit slit. Wave optics is also naturally applicable to calculations of the self-seeding scheme efficiency, which include the monochromator transmittance and the effect of the mismatching between seed beam and electron beam. Simulations show that the FEL power reaches 1 TW and that the spectral density for a TW pulse is about two orders of magnitude higher than that for the SASE pulse at saturation.

Grating monochromator for soft X-ray self-seeding the European XFEL

International Nuclear Information System (INIS)

Serkez, Svitozar; Kocharyan, Vitali; Saldin, Evgeni; Geloni, Gianluca

2013-02-01

Self-seeding is a promising approach to significantly narrow the SASE bandwidth of XFELs to produce nearly transform-limited pulses. The implementation of this method in the soft X-ray wavelength range necessarily involves gratings as dispersive elements. We study a very compact self-seeding scheme with a grating monochromator originally designed at SLAC, which can be straightforwardly installed in the SASE3 type undulator beamline at the European XFEL. The monochromator design is based on a toroidal VLS grating working at a fixed incidence angle mounting without entrance slit. It covers the spectral range from 300 eV to 1000 eV. The optical system was studied using wave optics method (in comparison with ray tracing) to evaluate the performance of the self-seeding scheme. Our wave optics analysis takes into account the actual beam wavefront of the radiation from the coherent FEL source, third order aberrations, and errors from each optical element. Wave optics is the only method available, in combination with FEL simulations, for the design of a self-seeding monochromator without exit slit. We show that, without exit slit, the self-seeding scheme is distinguished by the much needed experimental simplicity, and can practically give the same resolving power (about 7000) as with an exit slit. Wave optics is also naturally applicable to calculations of the self-seeding scheme efficiency, which include the monochromator transmittance and the effect of the mismatching between seed beam and electron beam. Simulations show that the FEL power reaches 1 TW and that the spectral density for a TW pulse is about two orders of magnitude higher than that for the SASE pulse at saturation.

Metrology of variable-line-spacing x-ray gratings using the APS Long Trace Profiler

Science.gov (United States)

Sheung, Janet; Qian, Jun; Sullivan, Joseph; Thomasset, Muriel; Manton, Jonathan; Bean, Sunil; Takacs, Peter; Dvorak, Joseph; Assoufid, Lahsen

2017-09-01

As resolving power targets have increased with each generation of beamlines commissioned in synchrotron radiation facilities worldwide, diffraction gratings are quickly becoming crucial optical components for meeting performance targets. However, the metrology of variable-line-spacing (VLS) gratings for high resolution beamlines is not widespread; in particular, no metrology facility at any US DOE facility is currently equipped to fully characterize such gratings. To begin to address this issue, the Optics Group at the Advanced Photon Source at Argonne, in collaboration with SOLEIL and with support from Brookhaven National Laboratory (BNL), has developed an alternative beam path addition to the Long Trace Profiler (LTP) at Argonne's Advanced Photon Source. This significantly expands the functionality of the LTP not only to measure mirrors surface slope profile at normal incidence, but also to characterize the groove density of VLS diffraction gratings in the Littrow incidence up to 79°, which covers virtually all diffraction gratings used at synchrotrons in the first order. The LTP light source is a 20mW HeNe laser, which yields enough signal for diffraction measurements to be performed on low angle blazed gratings optimized for soft X-ray wavelengths. We will present the design of the beam path, technical requirements for the optomechanics, and our data analysis procedure. Finally, we discuss challenges still to be overcome and potential limitations with use of the LTP to perform metrology on diffraction gratings.

Hard-x-ray phase-difference microscopy with a low-brilliance laboratory x-ray source

International Nuclear Information System (INIS)

Kuwabara, Hiroaki; Yashiro, Wataru; Harasse, Sebastien; Momose, Atsushi; Mizutani, Haruo

2011-01-01

We have developed a hard-X-ray phase-imaging microscopy method using a low-brilliance X-ray source. The microscope consists of a sample, a Fresnel zone plate, a transmission grating, and a source grating creating an array of mutually incoherent X-ray sources. The microscope generates an image exhibiting twin features of the sample with opposite signs separated by a distance, which is processed to generate a phase image. The method is quantitative even for non-weak-phase objects that are difficult to be quantitatively examined by the widely used Zernike phase-contrast microscopy, and it has potentially broad applications in the material and biological science fields. (author)

Synchrotron radiation calibration for soft X-ray detector

International Nuclear Information System (INIS)

Ning, Jiamin; Guo, Cun; Xu, Rongkun; Jiang, Shilun; Xu, Zeping; Chen, Jinchuan; Xia, Guangxin; Xue, Feibiao; Qin, Yi

2009-04-01

The calibration experiments were carried out to X-ray film, scintillator and transmission grating by employing the soft X-ray station at 3W1B beam-line in Beijing synchrotron Radiation Facility. The experiments presented the black intensity curve and energy response curve of soft X-ray film. And the experimental results can be used in diagnosis of X-ray radiation characterization of Z-pinch, such as in the measurement of soft X-ray Power Meter, grating spectrometer, pinhole camera and one-dimension imaging system which can ensure precision of Z-pinch results. (authors)

Measurements and simulations analysing the noise behaviour of grating-based X-ray phase-contrast imaging

Energy Technology Data Exchange (ETDEWEB)

Weber, T., E-mail: thomas.weber@physik.uni-erlangen.de [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Bartl, P.; Durst, J. [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Haas, W. [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); University of Erlangen-Nuremberg, Pattern Recognition Lab, Martensstr. 3, 91058 Erlangen (Germany); Michel, T.; Ritter, A.; Anton, G. [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany)

2011-08-21

In the last decades, phase-contrast imaging using a Talbot-Lau grating interferometer is possible even with a low-brilliance X-ray source. With the potential of increasing the soft-tissue contrast, this method is on its way into medical imaging. For this purpose, the knowledge of the underlying physics of this technique is necessary. With this paper, we would like to contribute to the understanding of grating-based phase-contrast imaging by presenting results on measurements and simulations regarding the noise behaviour of the differential phases. These measurements were done using a microfocus X-ray tube with a hybrid, photon-counting, semiconductor Medipix2 detector. The additional simulations were performed by our in-house developed phase-contrast simulation tool 'SPHINX', combining both wave and particle contributions of the simulated photons. The results obtained by both of these methods show the same behaviour. Increasing the number of photons leads to a linear decrease of the standard deviation of the phase. The number of used phase steps has no influence on the standard deviation, if the total number of photons is held constant. Furthermore, the probability density function (pdf) of the reconstructed differential phases was analysed. It turned out that the so-called von Mises distribution is the physically correct pdf, which was also confirmed by measurements. This information advances the understanding of grating-based phase-contrast imaging and can be used to improve image quality.

X-ray hot plasma diagnostics

International Nuclear Information System (INIS)

Cojocaru, E.

1984-11-01

X-ray plasma emission study is powerful diagnostic tool of hot plasmas. In this review article the main techniques of X-ray plasma emission measurement are shortly presented: X-ray spectrometry using absorbent filters, crystal and grating spectrometers, imaging techniques using pinhole cameras, X-ray microscopes and Fresnel zone plate cameras, X-ray plasma emission calorimetry. Advances in these techniques with examples for different hot plasma devices are also presentes. (author)

Noise analysis of grating-based x-ray differential phase-contrast imaging with angular signal radiography

International Nuclear Information System (INIS)

Faiz, Wali; Gao Kun; Wu Zhao; Wei Chen-Xi; Zan Gui-Bin; Tian Yang-Chao; Bao Yuan; Zhu Pei-Ping

2017-01-01

X-ray phase-contrast imaging is one of the novel techniques, and has potential to enhance image quality and provide the details of inner structures nondestructively. In this work, we investigate quantitatively signal-to-noise ratio (SNR) of grating-based x-ray phase contrast imaging (GBPCI) system by employing angular signal radiography (ASR). Moreover, photon statistics and mechanical error that is a major source of noise are investigated in detail. Results show the dependence of SNR on the system parameters and the effects on the extracted absorption, refraction and scattering images. Our conclusions can be used to optimize the system design for upcoming practical applications in the areas such as material science and biomedical imaging. (paper)

X-ray wavefront characterization using a rotating shearing interferometer technique.

Science.gov (United States)

Wang, Hongchang; Sawhney, Kawal; Berujon, Sébastien; Ziegler, Eric; Rutishauser, Simon; David, Christian

2011-08-15

A fast and accurate method to characterize the X-ray wavefront by rotating one of the two gratings of an X-ray shearing interferometer is described and investigated step by step. Such a shearing interferometer consists of a phase grating mounted on a rotation stage, and an absorption grating used as a transmission mask. The mathematical relations for X-ray Moiré fringe analysis when using this device are derived and discussed in the context of the previous literature assumptions. X-ray beam wavefronts without and after X-ray reflective optical elements have been characterized at beamline B16 at Diamond Light Source (DLS) using the presented X-ray rotating shearing interferometer (RSI) technique. It has been demonstrated that this improved method allows accurate calculation of the wavefront radius of curvature and the wavefront distortion, even when one has no previous information on the grating projection pattern period, magnification ratio and the initial grating orientation. As the RSI technique does not require any a priori knowledge of the beam features, it is suitable for routine characterization of wavefronts of a wide range of radii of curvature. © 2011 Optical Society of America

Design of a compact high-energy setup for x-ray phase-contrast imaging

Science.gov (United States)

Schüttler, Markus; Yaroshenko, Andre; Bech, Martin; Potdevin, Guillaume; Malecki, Andreas; Chabior, Michael; Wolf, Johannes; Tapfer, Arne; Meiser, Jan; Kunka, Danays; Amberger, Maximilian; Mohr, Jürgen; Pfeiffer, Franz

2014-03-01

The main shortcoming of conventional biomedical x-ray imaging is the weak soft-tissue contrast caused by the small differences in the absorption coefficients between different materials. This issue can be addressed by x-ray phasesensitive imaging approaches, e.g. x-ray Talbot-Lau grating interferometry. The advantage of the three-grating Talbot-Lau approach is that it allows to acquire x-ray phase-contrast and dark-field images with a conventional lab source. However, through the introduction of the grating interferometer some constraints are imposed on the setup geometry. In general, the grating pitch and the mean x-ray energy determine the setup dimensions. The minimal length of the setup increases linearly with energy and is proportional to p2, where p is the grating pitch. Thus, a high-energy (100 keV) compact grating-based setup for x-ray imaging can be realized only if gratings with aspect-ratio of approximately 300 and a pitch of 1-2 μm were available. However, production challenges limit the availability of such gratings. In this study we consider the use of non-binary phase-gratings as means of designing a more compact grating interferometer for phase-contrast imaging. We present simulation and experimental data for both monochromatic and polychromatic case. The results reveal that phase-gratings with triangular-shaped structures yield visibilities that can be used for imaging purposes at significantly shorter distances than binary gratings. This opens the possibility to design a high-energy compact setup for x-ray phase-contrast imaging. Furthermore, we discuss different techniques to achieve triangular-shaped phase-shifting structures.

X-ray phase imaging-From static observation to dynamic observation-

International Nuclear Information System (INIS)

Momose, A.; Yashiro, W.; Olbinado, M. P.; Harasse, S.

2012-01-01

We are attempting to expand the technology of X-ray grating phase imaging/tomography to enable dynamic observation. X-ray phase imaging has been performed mainly for static cases, and this challenge is significant since properties of materials (and hopefully their functions) would be understood by observing their dynamics in addition to their structure, which is an inherent advantage of X-ray imaging. Our recent activities in combination with white synchrotron radiation for this purpose are described. Taking advantage of the fact that an X-ray grating interferometer functions with X-rays of a broad energy bandwidth (and therefore high flux), movies of differential phase images and visibility images are obtained with a time resolution of a millisecond. The time resolution of X-ray phase tomography can therefore be a second. This study is performed as a part of a project to explore X-ray grating interferometry, and our other current activities are also briefly outlined.

Design and optimization of the grating monochromator for soft X-ray self-seeding FELs

Energy Technology Data Exchange (ETDEWEB)

Serkez, Svitozar

2015-10-15

The emergence of Free Electron Lasers (FEL) as a fourth generation of light sources is a breakthrough. FELs operating in the X-ray range (XFEL) allow one to carry out completely new experiments that probably most of the natural sciences would benefit. Self-amplified spontaneous emission (SASE) is the baseline FEL operation mode: the radiation pulse starts as a spontaneous emission from the electron bunch and is being amplified during an FEL process until it reaches saturation. The SASE FEL radiation usually has poor properties in terms of a spectral bandwidth or, on the other side, longitudinal coherence. Self-seeding is a promising approach to narrow the SASE bandwidth of XFELs significantly in order to produce nearly transformlimited pulses. It is achieved by the radiation pulse monochromatization in the middle of an FEL amplification process. Following the successful demonstration of the self-seeding setup in the hard X-ray range at the LCLS, there is a need for a self-seeding extension into the soft X-ray range. Here a numerical method to simulate the soft X-ray self seeding (SXRSS) monochromator performance is presented. It allows one to perform start-to-end self-seeded FEL simulations along with (in our case) GENESIS simulation code. Based on this method, the performance of the LCLS self-seeded operation was simulated showing a good agreement with an experiment. Also the SXRSS monochromator design developed in SLAC was adapted for the SASE3 type undulator beamline at the European XFEL. The optical system was studied using Gaussian beam optics, wave optics propagation method and ray tracing to evaluate the performance of the monochromator itself. Wave optics analysis takes into account the actual beam wavefront of the radiation from the coherent FEL source, third order aberrations and height errors from each optical element. The monochromator design is based on a toroidal VLS grating working at a fixed incidence angle mounting without both entrance and exit

Design and optimization of the grating monochromator for soft X-ray self-seeding FELs

International Nuclear Information System (INIS)

Serkez, Svitozar

2015-10-01

The emergence of Free Electron Lasers (FEL) as a fourth generation of light sources is a breakthrough. FELs operating in the X-ray range (XFEL) allow one to carry out completely new experiments that probably most of the natural sciences would benefit. Self-amplified spontaneous emission (SASE) is the baseline FEL operation mode: the radiation pulse starts as a spontaneous emission from the electron bunch and is being amplified during an FEL process until it reaches saturation. The SASE FEL radiation usually has poor properties in terms of a spectral bandwidth or, on the other side, longitudinal coherence. Self-seeding is a promising approach to narrow the SASE bandwidth of XFELs significantly in order to produce nearly transformlimited pulses. It is achieved by the radiation pulse monochromatization in the middle of an FEL amplification process. Following the successful demonstration of the self-seeding setup in the hard X-ray range at the LCLS, there is a need for a self-seeding extension into the soft X-ray range. Here a numerical method to simulate the soft X-ray self seeding (SXRSS) monochromator performance is presented. It allows one to perform start-to-end self-seeded FEL simulations along with (in our case) GENESIS simulation code. Based on this method, the performance of the LCLS self-seeded operation was simulated showing a good agreement with an experiment. Also the SXRSS monochromator design developed in SLAC was adapted for the SASE3 type undulator beamline at the European XFEL. The optical system was studied using Gaussian beam optics, wave optics propagation method and ray tracing to evaluate the performance of the monochromator itself. Wave optics analysis takes into account the actual beam wavefront of the radiation from the coherent FEL source, third order aberrations and height errors from each optical element. The monochromator design is based on a toroidal VLS grating working at a fixed incidence angle mounting without both entrance and exit

Quantitative breast tissue characterization using grating-based x-ray phase-contrast imaging

Science.gov (United States)

Willner, M.; Herzen, J.; Grandl, S.; Auweter, S.; Mayr, D.; Hipp, A.; Chabior, M.; Sarapata, A.; Achterhold, K.; Zanette, I.; Weitkamp, T.; Sztrókay, A.; Hellerhoff, K.; Reiser, M.; Pfeiffer, F.

2014-04-01

X-ray phase-contrast imaging has received growing interest in recent years due to its high capability in visualizing soft tissue. Breast imaging became the focus of particular attention as it is considered the most promising candidate for a first clinical application of this contrast modality. In this study, we investigate quantitative breast tissue characterization using grating-based phase-contrast computed tomography (CT) at conventional polychromatic x-ray sources. Different breast specimens have been scanned at a laboratory phase-contrast imaging setup and were correlated to histopathology. Ascertained tumor types include phylloides tumor, fibroadenoma and infiltrating lobular carcinoma. Identified tissue types comprising adipose, fibroglandular and tumor tissue have been analyzed in terms of phase-contrast Hounsfield units and are compared to high-quality, high-resolution data obtained with monochromatic synchrotron radiation, as well as calculated values based on tabulated tissue properties. The results give a good impression of the method’s prospects and limitations for potential tumor detection and the associated demands on such a phase-contrast breast CT system. Furthermore, the evaluated quantitative tissue values serve as a reference for simulations and the design of dedicated phantoms for phase-contrast mammography.

Development of full-field x-ray phase-tomographic microscope based on laboratory x-ray source

Science.gov (United States)

Takano, H.; Wu, Y.; Momose, A.

2017-09-01

An X-ray phase tomographic microscope that can quantitatively measure the refractive index of a sample in three dimensions with a high spatial resolution was developed by installing a Lau interferometer consisting of an absorption grating and a π/2 phase grating into the optics of an X-ray microscope. The optics comprises a Cu rotating anode X-ray source, capillary condenser optics, and a Fresnel zone plate for the objective. The microscope has two optical modes: a large-field-of-view mode (field of view: 65 μm x 65 μm) and a high-resolution mode (spatial resolution: 50 nm). Optimizing the parameters of the interferometer yields a self-image of the phase grating with 60% visibility. Through the normal fringe-scanning measurement, a twin phase image, which has an overlap of two phase image of opposite contrast with a shear distance much larger than system resolution, is generated. Although artifacts remain to some extent currently when a phase image is calculated from the twin phase image, this system can obtain high-spatial-resolution images resolving 50-nm structures. Phase tomography with this system has also been demonstrated using a phase object.

Fabrication and characterization of free-standing, high-line-density transmission gratings for the vacuum UV to soft X-ray range

NARCIS (Netherlands)

Goh, S.J.; Bastiaens, Hubertus M.J.; Vratzov, B.; Huang, Qiushi; Bijkerk, Frederik; Boller, Klaus J.

2015-01-01

We present state-of-the-art high resolution transmission gratings, applicable for spectroscopy in the vacuum ultraviolet (VUV) and the soft X-ray (SRX) wavelength range, fabricated with a novel process using ultraviolet based nano imprint lithography (UV-NIL). Free-standing, high-line-density

Broadband transmission masks, gratings and filters for extreme ultraviolet and soft X-ray lithography

International Nuclear Information System (INIS)

Brose, S.; Danylyuk, S.; Juschkin, L.; Dittberner, C.; Bergmann, K.; Moers, J.; Panaitov, G.; Trellenkamp, St.; Loosen, P.; Grützmacher, D.

2012-01-01

Lithography and patterning on a nanometre scale with extreme ultraviolet (EUV) and soft X-ray radiation allow creation of high resolution, high density patterns independent of a substrate type. To realize the full potential of this method, especially for EUV proximity printing and interference lithography, a reliable technology for manufacturing of the transmission masks and gratings should be available. In this paper we present a development of broadband amplitude transmission masks and gratings for extreme ultraviolet and soft X-ray lithography based on free-standing niobium membranes. In comparison with a standard silicon nitride based technology the transmission masks demonstrate high contrast not only for in-band EUV (13.5 nm) radiation but also for wavelengths below Si L-absorption edge (12.4 nm). The masks and filters with free standing areas up to 1000 × 1000 μm 2 and 100 nm to 300 nm membrane thicknesses are shown. Electron beam structuring of an absorber layer with dense line and dot patterns with sub-50 nm structures is demonstrated. Diffractive and filtering properties of obtained structures are examined with EUV radiation from a gas discharge plasma source. - Highlights: ► Broadband transmission masks for EUV proximity and interference lithography. ► Technology for free standing niobium membranes with areas up to 1 mm 2 . ► High density patterns with periods of 100 nm and structure sizes below 40 nm. ► Measured diffraction efficiency at 11 nm is in agreement with the theory. ► Produced masks can be effectively used with wavelengths between 6 nm and 17 nm.

The simulated spectrum of the OGRE X-ray EM-CCD camera system

Science.gov (United States)

Lewis, M.; Soman, M.; Holland, A.; Lumb, D.; Tutt, J.; McEntaffer, R.; Schultz, T.; Holland, K.

2017-12-01

The X-ray astronomical telescopes in use today, such as Chandra and XMM-Newton, use X-ray grating spectrometers to probe the high energy physics of the Universe. These instruments typically use reflective optics for focussing onto gratings that disperse incident X-rays across a detector, often a Charge-Coupled Device (CCD). The X-ray energy is determined from the position that it was detected on the CCD. Improved technology for the next generation of X-ray grating spectrometers has been developed and will be tested on a sounding rocket experiment known as the Off-plane Grating Rocket Experiment (OGRE). OGRE aims to capture the highest resolution soft X-ray spectrum of Capella, a well-known astronomical X-ray source, during an observation period lasting between 3 and 6 minutes whilst proving the performance and suitability of three key components. These three components consist of a telescope made from silicon mirrors, gold coated silicon X-ray diffraction gratings and a camera that comprises of four Electron-Multiplying (EM)-CCDs that will be arranged to observe the soft X-rays dispersed by the gratings. EM-CCDs have an architecture similar to standard CCDs, with the addition of an EM gain register where the electron signal is amplified so that the effective signal-to-noise ratio of the imager is improved. The devices also have incredibly favourable Quantum Efficiency values for detecting soft X-ray photons. On OGRE, this improved detector performance allows for easier identification of low energy X-rays and fast readouts due to the amplified signal charge making readout noise almost negligible. A simulation that applies the OGRE instrument performance to the Capella soft X-ray spectrum has been developed that allows the distribution of X-rays onto the EM-CCDs to be predicted. A proposed optical model is also discussed which would enable the missions minimum success criteria's photon count requirement to have a high chance of being met with the shortest possible

Quantitative x-ray dark-field computed tomography

International Nuclear Information System (INIS)

Bech, M; Pfeiffer, F; Bunk, O; Donath, T; David, C; Feidenhans'l, R

2010-01-01

The basic principles of x-ray image formation in radiology have remained essentially unchanged since Roentgen first discovered x-rays over a hundred years ago. The conventional approach relies on x-ray attenuation as the sole source of contrast and draws exclusively on ray or geometrical optics to describe and interpret image formation. Phase-contrast or coherent scatter imaging techniques, which can be understood using wave optics rather than ray optics, offer ways to augment or complement the conventional approach by incorporating the wave-optical interaction of x-rays with the specimen. With a recently developed approach based on x-ray optical gratings, advanced phase-contrast and dark-field scatter imaging modalities are now in reach for routine medical imaging and non-destructive testing applications. To quantitatively assess the new potential of particularly the grating-based dark-field imaging modality, we here introduce a mathematical formalism together with a material-dependent parameter, the so-called linear diffusion coefficient and show that this description can yield quantitative dark-field computed tomography (QDFCT) images of experimental test phantoms.

Development of soft x-ray optical elements at the advanced photon research center

International Nuclear Information System (INIS)

Ishino, Masahiko; Yoda, Osamu; Koike, Masato; Sano, Kazuo; Iwasaki, Hiroshi

2003-01-01

We have been developing soft X-ray optical elements such as diffraction gratings and multilayer mirrors to applied to X-ray plasma sources and X-ray lasers and so on. In the field of the development of diffraction gratings, the laminar-type holographic gratings for flat-field spectrographs were found to be very effective in suppressing the higher orders and stray-light level. The fabricated holographic grating has a comparable spectral resolution to the replica commercial grating. In the development of the soft X-ray multilayer mirrors, the improvement of the heat stability of the Mo/Si multilayer was carried out. We have found that the Mo/SiO 2 /Si/SiO 2 multilayer having the SiO 2 layer thicknesses of 0.5 nm at the Si-on-Mo interface and of 1.5 nm at the Mo-on-Si interface has thermally stable structure up to 500degC and maintains high soft X-ray reflectivity after annealing at 400degC. In addition, we have developed an evaluation system capable of measuring the wavelength and angular characteristics of the reflectivity and diffraction efficiency of soft X-ray optical elements. (author)

X-Ray Spectrometer For ROSAT II (SPECTROSAT)

Science.gov (United States)

Predehl, Peter; Brauninger, Heinrich

1986-01-01

The objective transmission grating was one of the earliest inventions in the field of X-ray astronomy and has been incorporated into Skylab, HERO-P, and EXOTAT. In recent years there have been advances in grating technology and spectrometer design. A high precision mechanical ruling and replication process for manufacturing large self-supporting transmission gratings has been developed by an industrial manufacturer in cooperation with the Max-Planck-Institute (MPI). Theoretical analyses have determined the optimum configuration of the grating facets and the grating surface in order to correct third order aberations and obtain maximum resolving power. We have verified experimentally that the predicted efficiencies may be achieved. In addition, an experimental study of large grating assemblies for space telescopes was made in industry with scientific guidance by MPI. Main objectives of this study were the determination of mechanical loads during launch, as well as the design, construction and fabrication of a representative model of a ROSAT grating ring. Performancy studies including instrument pro-perties as well as the simulated radiation from hot plasmas have shown the ability of SPECTROSAT to perform high efficiency, high resolution line-spectroscopy on a wide variety of cosmic X-ray sources.

Soft x-ray spectrographs for solar observations

International Nuclear Information System (INIS)

Bruner, M.E.

1988-01-01

This paper surveys some of the recent advances in the state of the art of soft X-ray spectrometers, particularly as they might be applied to Solar Observations. The discussions center on the windowless region from roughly 1 to 100 A, and covers both grating and crystal instruments. The author begins with a short discussion of the solar soft X-ray spectrum and its interpretation, followed by a few general comments on problems peculiar to soft X-ray instruments. The paper reviews of recent developments in spectrometer optical design, which has been a lively field during the last dozen years. This is particularly true in the case of grating spectrometers. The paper concludes with a short section on telescope considerations, and some remarks on future flight opportunities

Determination of the Modulation Transfer Function of Screen-Film Combinations in X-ray photography by the grating method

International Nuclear Information System (INIS)

Hoeschen, D.

1987-01-01

An intercomparison experiment concerning the determination of the Modulation Transfer Function (MTF) of Screen-Film Combinations in x-ray photography by the grating method was made. Six laboratories located in four countries participated. Each laboratory has used its own, individually developed measurement procedure. The results have shown a surprisingly good agreement, the standard deviation (1 σ value) of MTF values reported by the different laboratories was about ± 0.02

Differential phase contrast setup for a non coherent beamline at HASYLAB using hard X-ray grating interferometer

Energy Technology Data Exchange (ETDEWEB)

Herzen, Julia; Beckmann, Felix; Haibel, Astrid; Schreyer, Andreas [GKSS Research Centre, Geesthacht (Germany); Donath, Tilman; David, Christian; Gruenzweig, Christian [Paul Scherrer Institute, Villigen PSI (Switzerland); Pfeiffer, Franz [Paul Scherrer Institute, Villigen PSI (Switzerland); EPF Lausanne, Lausanne (Switzerland)

2009-07-01

Phase-contrast imaging is a common technique to visualize soft tissue with much higher contrast than the conventional absorption-contrast imaging. Differential phase contrast (DPC), developed at PSI, Switzerland, makes use of a hard x-ray grating interferometer and allows for phase-contrast imaging with high brilliance synchrotron sources as well as with conventional x-ray tubes. It is recently reported also to provide dark field information that is very sensitive to micro structures like porosity within the materials. Here we present the plans to adopt the DPC technique to the HARWI-II materials science beamline, operated by GKSS Research Centre, in cooperation with DESY, Hamburg. This will offer an amount of new applications especially in the field of materials science like for example characterizing new light weight materials like magnesium and studying its corrosion as implant material.

Quantitative phase imaging using quadri-wave lateral shearing interferometry. Application to X-ray domain

International Nuclear Information System (INIS)

Rizzi, Julien

2013-01-01

Since Roentgen discovered X-rays, X-ray imaging systems are based on absorption contrast. This technique is inefficient for weakly absorbing objects. As a result, X-ray standard radiography can detect bones lesions, but cannot detect ligament lesions. However, phase contrast imaging can overcome this limitation. Since the years 2000, relying on former works of opticians, X-ray scientists are developing phase sensitive devices compatible with industrial applications such as medical imaging or non destructive control. Standard architectures for interferometry are challenging to implement in the X-ray domain. This is the reason why grating based interferometers became the most promising devices to envision industrial applications. They provided the first x-ray phase contrast images of living human samples. Nevertheless, actual grating based architectures require the use of at least two gratings, and are challenging to adapt on an industrial product. So, the aim of my thesis was to develop a single phase grating interferometer. I demonstrated that such a device can provide achromatic and propagation invariant interference patterns. I used this interferometer to perform quantitative phase contrast imaging of a biological fossil sample and x-ray at mirror metrology. (author)

X-ray Talbot interferometry with capillary plates

International Nuclear Information System (INIS)

Momose, Atsushi; Kawamoto, Shinya

2006-01-01

An X-ray Talbot interferometer consisting of two capillary plates, which were used as X-ray amplitude gratings, was evaluated for X-ray phase imaging. A theoretical aspect of capillary X-ray Talbot interferometry is presented with a preliminary operation result using synchrotron radiation. A two-dimensional X-ray Talbot effect, or self-imaging effect, which was the basis of Talbot interferometry, was observed with the capillary plate, and moire images formed by the X-ray Talbot interferometer exhibited contrasts corresponding to the differential phase shift caused by phase objects placed in front of the interferometer. Finally, the possibility of quantitative phase measurement with a fringe scanning technique is discussed. (author)

X-ray phase scanning setup for non-destructive testing using Talbot-Lau interferometer

Science.gov (United States)

Bachche, S.; Nonoguchi, M.; Kato, K.; Kageyama, M.; Koike, T.; Kuribayashi, M.; Momose, A.

2016-09-01

X-ray grating interferometry has a great potential for X-ray phase imaging over conventional X-ray absorption imaging which does not provide significant contrast for weakly absorbing objects and soft biological tissues. X-ray Talbot and Talbot-Lau interferometers which are composed of transmission gratings and measure the differential X-ray phase shifts have gained popularity because they operate with polychromatic beams. In X-ray radiography, especially for nondestructive testing in industrial applications, the feasibility of continuous sample scanning is not yet completely revealed. A scanning setup is frequently advantageous when compared to a direct 2D static image acquisition in terms of field of view, exposure time, illuminating radiation, etc. This paper demonstrates an efficient scanning setup for grating-based Xray phase imaging using laboratory-based X-ray source. An apparatus consisting of an X-ray source that emits X-rays vertically, optical gratings and a photon-counting detector was used with which continuously moving objects across the field of view as that of conveyor belt system can be imaged. The imaging performance of phase scanner was tested by scanning a long continuous moving sample at a speed of 5 mm/s and absorption, differential-phase and visibility images were generated by processing non-uniform moire movie with our specially designed phase measurement algorithm. A brief discussion on the feasibility of phase scanner with scanning setup approach including X-ray phase imaging performance is reported. The successful results suggest a breakthrough for scanning objects those are moving continuously on conveyor belt system non-destructively using the scheme of X-ray phase imaging.

High efficiency spectro graphs for the EUV and soft x-rays

International Nuclear Information System (INIS)

Cash, W.

1983-01-01

A basic need of modern UV and x-ray astronomy is the capability to perform high resolution spectroscopy of faint stars. The use of modern grazing incidence optics can be coupled to high blaze angle reflection gratings used in the conical diffraction mount to offer a versatile, efficient approach to the design problem. The authors discuss two designs of interest: an echelle spectrograph for use longward of 100 A, and an Objective Reflection Grating Spectrograph for use in the soft x-rays. General design considerations and measurements of grating efficiencies are also presented

Comment on ‘A new method for fusion, denoising and enhancement of x-ray images retrieved from Talbot–Lau grating interferometry’

International Nuclear Information System (INIS)

Scholkmann, Felix; Revol, Vincent; Kaufmann, Rolf; Kottler, Christian

2015-01-01

In a recent paper (Scholkamm et al 2014 Phys. Med. Biol. 59 1425–40) we presented a new image denoising, fusion and enhancement framework for combining and optimal visualization of x-ray attenuation contrast, differential phase contrast and dark-field contrast images retrieved from x-ray Talbot–Lau grating interferometry. In this comment we give additional information and report about the application of our framework to breast cancer tissue which we presented in our paper as an example. The applied procedure is suitable for a qualitative comparison of different algorithms. For a quantitative juxtaposition original data would however be needed as an input. (comment and reply)

Optical and X-ray studies of Compact X-ray Binaries in NGC 5904

Science.gov (United States)

Bhalotia, Vanshree; Beck-Winchatz, Bernhard

2018-06-01

Due to their high stellar densities, globular cluster systems trigger various dynamical interactions, such as the formation of compact X-ray binaries. Stellar collisional frequencies have been correlated to the number of X-ray sources detected in various clusters and we hope to measure this correlation for NGC 5904. Optical fluxes of sources from archival HST images of NGC 5904 have been measured using a DOLPHOT PSF photometry in the UV, optical and near-infrared. We developed a data analysis pipeline to process the fluxes of tens of thousands of objects using awk, python and DOLPHOT. We plot color magnitude diagrams in different photometric bands in order to identify outliers that could be X-ray binaries, since they do not evolve the same way as singular stars. Aligning previously measured astrometric data for X-ray sources in NGC 5904 from Chandra with archival astrometric data from HST will filter out the outlier objects that are not X-ray producing, and provide a sample of compact binary systems that are responsible for X-ray emission in NGC 5904. Furthermore, previously measured X-ray fluxes of NGC 5904 from Chandra have also been used to measure the X-ray to optical flux ratio and identify the types of compact X-ray binaries responsible for the X-ray emissions in NGC 5904. We gratefully acknowledge the support from the Illinois Space Grant Consortium.

Image Analysis for X-ray Imaging of Food

DEFF Research Database (Denmark)

Einarsdottir, Hildur

for quality and safety evaluation of food products. In this effort the fields of statistics, image analysis and statistical learning are combined, to provide analytical tools for determining the aforementioned food traits. The work demonstrated includes a quantitative analysis of heat induced changes......X-ray imaging systems are increasingly used for quality and safety evaluation both within food science and production. They offer non-invasive and nondestructive penetration capabilities to image the inside of food. This thesis presents applications of a novel grating-based X-ray imaging technique...... and defect detection in food. Compared to the complex three dimensional analysis of microstructure, here two dimensional images are considered, making the method applicable for an industrial setting. The advantages obtained by grating-based imaging are compared to conventional X-ray imaging, for both foreign...

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility.

Science.gov (United States)

Reverdin, Charles; Thais, Frédéric; Loisel, Guillaume; Busquet, M; Bastiani-Ceccotti, S; Blenski, T; Caillaud, T; Ducret, J E; Foelsner, W; Gilles, D; Gilleron, F; Pain, J C; Poirier, M; Serres, F; Silvert, V; Soullie, G; Turck-Chieze, S; Villette, B

2012-10-01

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ∼ 50. It has been used at the LULI-2000 laser facility at École Polytechnique (France) to measure the Δn = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility

International Nuclear Information System (INIS)

Reverdin, Charles; Caillaud, T.; Gilleron, F.; Pain, J. C.; Silvert, V.; Soullie, G.; Villette, B.; Thais, Frédéric; Loisel, Guillaume; Blenski, T.; Poirier, M.; Busquet, M.; Bastiani-Ceccotti, S.; Serres, F.; Ducret, J. E.; Foelsner, W.; Gilles, D.; Turck-Chieze, S.

2012-01-01

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ∼ 50. It has been used at the LULI-2000 laser facility at École Polytechnique (France) to measure the Δn = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility

Energy Technology Data Exchange (ETDEWEB)

Reverdin, Charles; Caillaud, T.; Gilleron, F.; Pain, J. C.; Silvert, V.; Soullie, G.; Villette, B. [CEA, DAM, DIF, 91297 Arpajon (France); Thais, Frederic; Loisel, Guillaume; Blenski, T.; Poirier, M. [CEA, DSM, IRAMIS, Service Photons, Atomes et Molecules, 91191 Gif-sur-Yvette (France); Busquet, M. [ARTEP Inc, Ellicott City, Maryland 21042 (United States); Bastiani-Ceccotti, S.; Serres, F. [LULI, Ecole Polytechnique, CNRS, CEA, UPMC, route de Saclay, 91128 Palaiseau (France); Ducret, J. E. [CELIA, UMR5107, CEA, CNRS, Universite de Bordeaux, 33400 Talence (France); Foelsner, W. [Max Planck Instituet fuer Quantum Optik, 85748 Garching (Germany); Gilles, D.; Turck-Chieze, S. [CEA, DSM, IRFU, Service d' astrophysique, 91191 Gif-sur-Yvette (France)

2012-10-15

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution {approx} 50. It has been used at the LULI-2000 laser facility at Ecole Polytechnique (France) to measure the {Delta}n = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

Soft X-Ray amplification in laser plasmas

International Nuclear Information System (INIS)

Louis-Jacquet, M.

1988-01-01

The principles, experiments and theoretical models of soft x-ray, amplification, produced in laser plasmas, are studied. In the discussion of the principles, the laser plasma medium, the definition of the gain, the population inversions, saturation and superradiance are described. The results concerning recombination and collisional excitation experiments, as well as experimental devices are shown. A complete physical simulation to design and interpret x-ray laser experiments is given. Applications of x-ray lasers in grating production techniques, in contact microscopy and holography are considered

Soft X-ray spectrographs for solar observations

Science.gov (United States)

Bruner, M. E.

1988-01-01

Recent advances in soft X-ray spectrometery are reviewed, with emphasis on techniques for studying the windowless region from roughly 1-100 A. Recent technological developments considered include multilayer mirrors, large-format CCD detectors which are sensitive to X-rays, position-sensitive photon counting detectors, new kinds of X-ray films, and optical systems based on gratings with nonuniform ruling spacings. Improvements in the extent and accuracy of the atomic physics data sets on which the analysis of spectroscopic observatons depend are also discussed.

An introduction to the water recovery x-ray rocket

Science.gov (United States)

Miles, Drew M.; McEntaffer, Randall L.; Schultz, Ted B.; Donovan, Benjamin D.; Tutt, James H.; Yastishock, Daniel; Steiner, Tyler; Hillman, Christopher R.; McCoy, Jake A.; Wages, Mitchell; Hull, Sam; Falcone, Abe; Burrows, David N.; Chattopadhyay, Tanmoy; Anderson, Tyler; McQuaide, Maria

2017-08-01

The Water Recovery X-ray Rocket (WRXR) is a sounding rocket payload that will launch from the Kwajalein Atoll in April 2018 and seeks to be the first astrophysics sounding rocket payload to be water recovered by NASA. WRXR's primary instrument is a grating spectrometer that consists of a mechanical collimator, X-ray reflection gratings, grazing-incidence mirrors, and a hybrid CMOS detector. The instrument will obtain a spectrum of the diffuse soft X-ray emission from the northern part of the Vela supernova remnant and is optimized for 3rd and 4th order OVII emission. Utilizing a field of view of 3.25° × 3.25° and resolving power of λ/δλ ≍40-50 in the lines of interest, the WRXR spectrometer aims to achieve the most highly-resolved spectrum of Vela's diffuse soft X-ray emission. This paper presents introductions to the payload and the science target.

Single order soft X-ray diffraction with quasi-random radius pinhole array spectroscopic photon sieves

International Nuclear Information System (INIS)

Zhang Qiang-Qiang; Wei Lai; Yang Zu-Hua; Qian Feng; Fan Quan-Ping; Zhang Bo; Gu Yu-Qiu; Cao Lei-Feng

2014-01-01

A novel single order diffraction grating in the soft X-ray region, called quasi-random radius pinhole array spectroscopic photon sieves (QRSPS), is proposed in this paper. This new grating is composed of pinholes on a substrate, whose radii are quasi-random, while their centers are regular. Analysis proves that its transmittance function across the grating bar is similar to that of sinusoidal transmission gratings. Simulation results show that the QRSPS can suppress higher-order diffraction effectively. And the QRSPS would still retain its characteristic of single order diffraction when we take the effect of X-ray penetration into account. These properties indicate that the QRSPS can be used in the soft X-ray spectra measurement. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

Phase-space evolution of x-ray coherence in phase-sensitive imaging.

Science.gov (United States)

Wu, Xizeng; Liu, Hong

2008-08-01

X-ray coherence evolution in the imaging process plays a key role for x-ray phase-sensitive imaging. In this work we present a phase-space formulation for the phase-sensitive imaging. The theory is reformulated in terms of the cross-spectral density and associated Wigner distribution. The phase-space formulation enables an explicit and quantitative account of partial coherence effects on phase-sensitive imaging. The presented formulas for x-ray spectral density at the detector can be used for performing accurate phase retrieval and optimizing the phase-contrast visibility. The concept of phase-space shearing length derived from this phase-space formulation clarifies the spatial coherence requirement for phase-sensitive imaging with incoherent sources. The theory has been applied to x-ray Talbot interferometric imaging as well. The peak coherence condition derived reveals new insights into three-grating-based Talbot-interferometric imaging and gratings-based x-ray dark-field imaging.

SMART-X: Square Meter, Arcsecond Resolution Telescope for X-rays

Science.gov (United States)

Vikhlinin, Alexey; SMART-X Collaboration

2013-04-01

SMART-X is a concept for a next-generation X-ray observatory with large-area, 0.5" angular resolution grazing incidence adjustable X-ray mirrors, high-throughput critical angle transmission gratings, and X-ray microcalorimeter and CMOS-based imager in the focal plane. High angular resolution is enabled by new technology based on controlling the shape of mirror segments using thin film piezo actuators deposited on the back surface. Science applications include observations of growth of supermassive black holes since redshifts of ~10, ultra-deep surveys over 10's of square degrees, galaxy assembly at z=2-3, as well as new opportunities in the high-resolution X-ray spectroscopy and time domains. We also review the progress in technology development, tests, and mission design over the past year.

The advantages of soft X-rays and cryogenic spectrometers for measuring chemical speciation by X-ray spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Drury, Owen B. [Lawrence Livermore National Laboratory, Advanced Detector Group, 7000 East Ave., L-270, Livermore, CA 94550 (United States); UC Davis, Biophysics Graduate Group, 1 Shields Ave, CA 95616 (United States); LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States); Friedrich, Stephan [Lawrence Livermore National Laboratory, Advanced Detector Group, 7000 East Ave., L-270, Livermore, CA 94550 (United States) and LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States)]. E-mail: friedrich1@llnl.gov; George, Simon J. [LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States); Cramer, Stephen P. [UC Davis, Biophysics Graduate Group, 1 Shields Ave, CA 95616 (United States); LBNL, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, MS 6-2100, Berkeley, CA 92720 (United States)

2006-04-15

We have built a 36-pixel high-resolution superconducting tunnel junction (STJ) soft X-ray spectrometer for chemical analysis of dilute metals by fluorescence-detected X-ray absorption spectroscopy (XAS) at the Advanced Light Source synchrotron. Soft X-ray absorption edges are preferred over traditional hard X-ray spectroscopy at the K-edges, since they have narrower natural linewidths and exhibit stronger chemical shifts. STJ detectors are preferred in the soft X-ray band over traditional Ge or grating spectrometers, since they have sufficient energy resolution to resolve transition metal L and M lines from light element K emission, and sufficient detection efficiency to measure the weak lines of dilute specimens within an acceptable time. We demonstrate the capabilities of our STJ spectrometer for chemical analysis with soft XAS measurements of molybdenum speciation on the Mo M{sub 4,5}-edges.

Diagnostics for an XUV/soft x-ray laser

International Nuclear Information System (INIS)

Kauffman, R.L.; Matthews, D.L.; Ceglio, N.; Medecki, H.

1984-01-01

We have begun investigating the production of an XUV/soft x-ray laser, using our high-powered glass lasers as drivers. A major diagnostic for lasing is the measure of the absolute power produced in the lasing line. I have developed a spectrograph to time-resolved lasing lines in the energy range from 50 eV to greater than 200 eV. the spectrograph combines a transmission grating and x-ray streak camera to produce a flat field instrument. A cylindrical mirror is used in front of the grating to image the source and act as a collecting optic. The efficiency of the components is calibrated so that absolute intensities can be measured. I will compare the performance of this instrument with reflection grating systems. I will also discuss planned improvements to the system which should increase total throughput, image quality, and resolving power

Some observational aspects of compact galactic X-ray sources

International Nuclear Information System (INIS)

Heise, J.

1982-01-01

This thesis contains the following observations of compact galactic X-ray sources: i) the X-ray experiments onboard the Astronomical Netherlands Satellite ANS, ii) a rocket-borne ultra soft X-ray experiment and iii) the Objective Grating Spectrometer onboard the EINSTEIN observatory. In Chapter I the various types of compact galactic X-ray sources are reviewed and put into the perspective of earlier and following observations. In Chapter II the author presents some of the observations of high luminosity X-ray sources, made with ANS, including the detection of soft X-rays from the compact X-ray binary Hercules X-1 and the ''return to the high state'' of the black hole candidate Cygnus X-1. Chapter III deals with transient X-ray phenomena. Results on low luminosity galactic X-ray sources are collected in Chapter IV. (Auth.)

ON THE X-RAY BALDWIN EFFECT IN ACTIVE GALACTIC NUCLEI OBSERVED BY THE CHANDRA HIGH-ENERGY GRATING

International Nuclear Information System (INIS)

Shu, X. W.; Wang, J. X.; Jiang, P.; Zhou, Y. Y.; Yaqoob, T.

2012-01-01

Using Chandra high-energy grating (HEG) observations of 32 active galactic nuclei (AGNs), we present a systematic study of the X-ray Baldwin effect (XBE; i.e., the anti-correlation between the narrow Fe Kα line equivalent width (EW) and X-ray continuum luminosity for AGN samples) with the highest spectral resolution currently available. We have previously reported an anti-correlation with EW∝L –0.22 2-10keV in an HEG sample, and the correlation is much weaker after averaging multiple observations of individual AGNs (EW∝L –0.13 2-10keV ). This indicates that rapid variation in the X-ray continuum plays an important role in producing the XBE, and such an effect should also be visible in individual AGNs. In this Letter, by normalizing the line EWs and continuum luminosities to the time-averaged values for each AGN in our sample with multiple HEG observations, we find a strong anti-correlation between EW and L X (EW/(EW)∝(L/(L)) –0.82±0.10 ), consistent with the XBE expected in an individual AGN if the narrow line flux remains constant while the continuum varies. This is first observational evidence that the Fe Kα line flux in a large sample of AGNs lacks a corresponding response to the continuum variation, supporting the fact that the narrow Fe-K line emission originates from a region far from the nucleus. We then performed Monte Carlo simulations to address whether the global XBE can be produced by X-ray continuum variation solely, and found that such an interpretation of the XBE cannot be ruled out statistically. One should thus be very cautious before drawing any scientific conclusion based on an observed XBE.

Transmission Grating and Optics Technology Development for the Arcus Explorer Mission

Science.gov (United States)

Heilmann, Ralf; Arcus Team

2018-01-01

Arcus is a high-resolution x-ray spectroscopy MIDEX mission selected for a Phase A concept study. It is designed to explore structure formation through measurements of hot baryon distributions, feedback from black holes, and the formation and evolution of stars, disks, and exoplanet atmospheres. The design provides unprecedented sensitivity in the 1.2-5 nm wavelength band with effective area above 450 sqcm and spectral resolution R > 2500. The Arcus technology is based on 12 m-focal length silicon pore optics (SPO) developed for the European Athena mission, and critical-angle transmission (CAT) x-ray diffraction gratings and x-ray CCDs developed at MIT. The modular design consists of four parallel channels, each channel holding an optics petal, followed by a grating petal. CAT gratings are lightweight, alignment insensitive, high-efficiency x-ray transmission gratings that blaze into high diffraction orders, leading to high spectral resolution. Each optics petal represents an azimuthal sub-aperture of a full Wolter optic. The sub-aperturing effect increases spectral resolving power further. Two CCD readout strips receive photons from each channel, including higher-energy photons in 0th order. Each optics petal holds 34 SPO modules. Each grating petal holds 34 grating windows, and each window holds 4-6 grating facets. A grating facet consists of a silicon grating membrane, bonded to a flexure frame that interfaces with the grating window. We report on a sequence of tests with increasing complexity that systematically increase the Technology Readiness Level (TRL) for the combination of CAT gratings and SPOs towards TLR 6. CAT gratings have been evaluated in x rays for diffraction efficiency (> 30% at 2.5 nm) and for resolving power (R> 10,000). A CAT grating/SPO combination was measured at R ~ 3100 at blaze angles smaller than design values, exceeding Arcus requirements. Efficiency and resolving power were not impacted by vibration and thermal testing of gratings. A

The Marshall Grazing Incidence X-ray Spectrometer

Science.gov (United States)

Kobayashi, Ken; Winebarger, Amy R.; Savage, Sabrina; Champey, Patrick; Cheimets, Peter N.; Hertz, Edward; Bruccoleri, Alexander R.; Golub, Leon; Ramsey, Brian; Ranganathan, Jaganathan; Marquez, Vanessa; Allured, Ryan; Parker, Theodore; Heilmann, Ralf K.; Schattenburg, Mark L.

2017-08-01

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a NASA sounding rocket instrument designed to obtain spatially resolved soft X-ray spectra of the solar atmosphere in the 6-24 Å (0.5-2.0 keV) range. The instrument consists of a single shell Wolter Type-I telescope, a slit, and a spectrometer comprising a matched pair of grazing incidence parabolic mirrors and a planar varied-line space diffraction grating. The instrument is designed to achieve a 50 mÅ spectral resolution and 5 arcsecond spatial resolution along a +/-4-arcminute long slit, and launch is planned for 2019. We report on the status and our approaches for fabrication and alignment for this novel optical system. The telescope and spectrometer mirrors are replicated nickel shells, and are currently being fabricated at the NASA Marshall Space Flight Center. The diffraction grating is currently under development by the Massachusetts Institute of Technology (MIT); because of the strong line spacing variation across the grating, it will be fabricated through e-beam lithography.

Mechanical design and performance evaluation for plane grating monochromator in a soft X-ray microscopy beamline at SSRF.

Science.gov (United States)

Gong, Xuepeng; Lu, Qipeng

2015-01-01

A new monochromator is designed to develop a high performance soft X-ray microscopy beamline at Shanghai Synchrotron Radiation Facility (SSRF). But owing to its high resolving power and high accurate spectrum output, there exist many technical difficulties. In the paper presented, as two primary design targets for the monochromator, theoretical energy resolution and photon flux of the beamline are calculated. For wavelength scanning mechanism, primary factors affecting the rotary angle errors are presented, and the measuring results are 0.15'' and 0.17'' for plane mirror and plane grating, which means that it is possible to provide sufficient scanning precision to specific wavelength. For plane grating switching mechanism, the repeatabilities of roll, yaw and pitch angles are 0.08'', 0.12'' and 0.05'', which can guarantee the high accurate switch of the plane grating effectively. After debugging, the repeatability of light spot drift reaches to 0.7'', which further improves the performance of the monochromator. The commissioning results show that the energy resolving power is higher than 10000 at Ar L-edge, the photon flux is higher than 1 × 108 photons/sec/200 mA, and the spatial resolution is better than 30 nm, demonstrating that the monochromator performs very well and reaches theoretical predictions.

Low Energy X-Ray Diagnostics - 1981.

Science.gov (United States)

1981-01-01

41MEAS) Opt. Comm., 9, 246, (1973); also Phys. Rev. A, ( MODELED ) .01 11, 989, (1975). 13. R. Thack, H. Mahr, C. L. Tang, and P. L. Hartman , Phys. Rev...Transmission Gratings: R. Tatchyn and I. Lindau 301 Analysis and Modeling Results Holographic X-Ray Gratings to be Produced at P.L. Csonka and R...orbit. The degree of polarization depends on the Calfonia ad CSR an8 eVstorage ring at Cornell electron energy, wavelength, and vertical viewing Univrsit

Pulse-front tilt caused by the use of a grating monochromator and self-seeding of soft X-ray FELs

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2012-03-15

Self-seeding is a promising approach to significantly narrow the SASE bandwidth of XFELs to produce nearly transform-limited pulses. The development of such schemes in the soft X-ray wavelength range necessarily involves gratings as dispersive elements. These introduce, in general, a pulse-front tilt, which is directly proportional to the angular dispersion. Pulse-front tilt may easily lead to a seed signal decrease by a factor two or more. Suggestions on how to minimize the pulse-front tilt effect in the self-seeding setup are given. (orig.)

Pulse-front tilt caused by the use of a grating monochromator and self-seeding of soft X-ray FELs

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

2012-03-01

Self-seeding is a promising approach to significantly narrow the SASE bandwidth of XFELs to produce nearly transform-limited pulses. The development of such schemes in the soft X-ray wavelength range necessarily involves gratings as dispersive elements. These introduce, in general, a pulse-front tilt, which is directly proportional to the angular dispersion. Pulse-front tilt may easily lead to a seed signal decrease by a factor two or more. Suggestions on how to minimize the pulse-front tilt effect in the self-seeding setup are given. (orig.)

Novelty detection of foreign objects in food using multi-modal X-ray imaging

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Emerson, Monica Jane; Clemmensen, Line Katrine Harder

2016-01-01

In this paper we demonstrate a method for novelty detection of foreign objects in food products using grating-based multimodal X-ray imaging. With this imaging technique three modalities are available with pixel correspondence, enhancing organic materials such as wood chips, insects and soft...... plastics not detectable by conventional X-ray absorption radiography. We conduct experiments, where several food products are imaged with common foreign objects typically found in the food processing industry. To evaluate the benefit from using this multi-contrast X-ray technique over conventional X......-ray absorption imaging, a novelty detection scheme based on well known image- and statistical analysis techniques is proposed. The results show that the presented method gives superior recognition results and highlights the advantage of grating-based imaging....

High sensitivity phase retrieval method in grating-based x-ray phase contrast imaging

Energy Technology Data Exchange (ETDEWEB)

Wu, Zhao; Gao, Kun; Chen, Jian; Wang, Dajiang; Wang, Shenghao; Chen, Heng; Bao, Yuan; Shao, Qigang; Wang, Zhili, E-mail: wangnsrl@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Zhang, Kai [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Zhu, Peiping; Wu, Ziyu, E-mail: wuzy@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China and Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

2015-02-15

Purpose: Grating-based x-ray phase contrast imaging is considered as one of the most promising techniques for future medical imaging. Many different methods have been developed to retrieve phase signal, among which the phase stepping (PS) method is widely used. However, further practical implementations are hindered, due to its complex scanning mode and high radiation dose. In contrast, the reverse projection (RP) method is a novel fast and low dose extraction approach. In this contribution, the authors present a quantitative analysis of the noise properties of the refraction signals retrieved by the two methods and compare their sensitivities. Methods: Using the error propagation formula, the authors analyze theoretically the signal-to-noise ratios (SNRs) of the refraction images retrieved by the two methods. Then, the sensitivities of the two extraction methods are compared under an identical exposure dose. Numerical experiments are performed to validate the theoretical results and provide some quantitative insight. Results: The SNRs of the two methods are both dependent on the system parameters, but in different ways. Comparison between their sensitivities reveals that for the refraction signal, the RP method possesses a higher sensitivity, especially in the case of high visibility and/or at the edge of the object. Conclusions: Compared with the PS method, the RP method has a superior sensitivity and provides refraction images with a higher SNR. Therefore, one can obtain highly sensitive refraction images in grating-based phase contrast imaging. This is very important for future preclinical and clinical implementations.

High sensitivity phase retrieval method in grating-based x-ray phase contrast imaging

International Nuclear Information System (INIS)

Wu, Zhao; Gao, Kun; Chen, Jian; Wang, Dajiang; Wang, Shenghao; Chen, Heng; Bao, Yuan; Shao, Qigang; Wang, Zhili; Zhang, Kai; Zhu, Peiping; Wu, Ziyu

2015-01-01

Purpose: Grating-based x-ray phase contrast imaging is considered as one of the most promising techniques for future medical imaging. Many different methods have been developed to retrieve phase signal, among which the phase stepping (PS) method is widely used. However, further practical implementations are hindered, due to its complex scanning mode and high radiation dose. In contrast, the reverse projection (RP) method is a novel fast and low dose extraction approach. In this contribution, the authors present a quantitative analysis of the noise properties of the refraction signals retrieved by the two methods and compare their sensitivities. Methods: Using the error propagation formula, the authors analyze theoretically the signal-to-noise ratios (SNRs) of the refraction images retrieved by the two methods. Then, the sensitivities of the two extraction methods are compared under an identical exposure dose. Numerical experiments are performed to validate the theoretical results and provide some quantitative insight. Results: The SNRs of the two methods are both dependent on the system parameters, but in different ways. Comparison between their sensitivities reveals that for the refraction signal, the RP method possesses a higher sensitivity, especially in the case of high visibility and/or at the edge of the object. Conclusions: Compared with the PS method, the RP method has a superior sensitivity and provides refraction images with a higher SNR. Therefore, one can obtain highly sensitive refraction images in grating-based phase contrast imaging. This is very important for future preclinical and clinical implementations

The X-ray Variability of Eta Car, 1996-2010

Science.gov (United States)

Corcoran, Michael F.; Hamaguchi, K.; Gull, T.; Owocki, S.; Pittard, J.

2010-01-01

X-ray photometry in the 2-10 keY band of the the supermassive binary star Eta Car has been measured with the Rossi X-ray Timing Explorer from 1996-2010. The ingress to X-ray minimum is consistent with a period of 2024 days. The 2009 X-ray minimum began on January 162009 and showed an unexpectedly abrupt recovery starting after 12 Feb 2009. The X-ray colors become harder about half-way through all three minima and continue until flux recovery. The behavior of the fluxes and X-ray colors for the most recent X-ray minimum, along with Chandra high resolution grating spectra at key phases suggests a significant change in the inner wind of Eta Car, a possible indicator that the star is entering a new unstable phase of mass loss.

Interferogram conditioning for improved Fourier analysis and application to X-ray phase imaging by grating interferometry.

Science.gov (United States)

Montaux-Lambert, Antoine; Mercère, Pascal; Primot, Jérôme

2015-11-02

An interferogram conditioning procedure, for subsequent phase retrieval by Fourier demodulation, is presented here as a fast iterative approach aiming at fulfilling the classical boundary conditions imposed by Fourier transform techniques. Interference fringe patterns with typical edge discontinuities were simulated in order to reveal the edge artifacts that classically appear in traditional Fourier analysis, and were consecutively used to demonstrate the correction efficiency of the proposed conditioning technique. Optimization of the algorithm parameters is also presented and discussed. Finally, the procedure was applied to grating-based interferometric measurements performed in the hard X-ray regime. The proposed algorithm enables nearly edge-artifact-free retrieval of the phase derivatives. A similar enhancement of the retrieved absorption and fringe visibility images is also achieved.

Absolutely calibrated, time-resolved measurements of soft x rays using transmission grating spectrometers at the Nike Laser Facility

International Nuclear Information System (INIS)

Weaver, J.L.; Feldman, U.; Seely, J.F.; Holland, G.; Serlin, V.; Klapisch, M.; Columbant, D.; Mostovych, A.

2001-01-01

Accurate simulation of pellet implosions for direct drive inertial confinement fusion requires benchmarking the codes with experimental data. The Naval Research Laboratory (NRL) has begun to measure the absolute intensity of radiation from laser irradiated targets to provide critical information for the radiatively preheated pellet designs developed by the Nike laser group. Two main diagnostics for this effort are two spectrometers incorporating three detection systems. While both spectrometers use 2500 lines/mm transmission gratings, one instrument is coupled to a soft x-ray streak camera and the other is coupled to both an absolutely calibrated Si photodiode array and a charge coupled device (CCD) camera. Absolute calibration of spectrometer components has been undertaken at the National Synchrotron Light Source at Brookhaven National Laboratories. Currently, the system has been used to measure the spatially integrated soft x-ray flux as a function of target material, laser power, and laser spot size. A comparison between measured and calculated flux for Au and CH targets shows reasonable agreement to one-dimensional modeling for two laser power densities

Computer-aided diagnosis of pulmonary diseases using x-ray darkfield radiography

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Yaroshenko, Andre; Velroyen, Astrid

2015-01-01

In this work we develop a computer-aided diagnosis (CAD) scheme for classification of pulmonary disease for grating-based x-ray radiography. In addition to conventional transmission radiography, the grating-based technique provides a dark-field imaging modality, which utilizes the scattering...... properties of the x-rays. This modality has shown great potential for diagnosing early stage emphysema and fibrosis in mouse lungs in vivo. The CAD scheme is developed to assist radiologists and other medical experts to develop new diagnostic methods when evaluating grating-based images. The scheme consists...... of three stages: (i) automatic lung segmentation; (ii) feature extraction from lung shape and dark-field image intensities; (iii) classification between healthy, emphysema and fibrosis lungs. A study of 102 mice was conducted with 34 healthy, 52 emphysema and 16 fibrosis subjects. Each image was manually...

The Water Recovery X-ray Rocket (WRX-R)

Science.gov (United States)

Miles, Drew

2017-08-01

The Water Recovery X-ray Rocket (WRX-R) is a diffuse soft X-ray spectrometer that will launch on a sounding rocket from the Kwajalein Atoll. WRX-R has a field of view of >10 deg2 and will observe the Vela supernova remnant. A mechanical collimator, state-of-the-art off-plane reflection grating array and hybrid CMOS detector will allow WRX to achieve the most highly-resolved spectrum of the Vela SNR ever recorded. In addition, this payload will fly a hard X-ray telescope that is offset from the soft X-ray spectrometer in order to observe the pulsar at the center of the remnant. We present here an introduction to the instrument, the expected science return, and an update on the state of the payload as we work towards launch.

Energy weighted x-ray dark-field imaging.

Science.gov (United States)

Pelzer, Georg; Zang, Andrea; Anton, Gisela; Bayer, Florian; Horn, Florian; Kraus, Manuel; Rieger, Jens; Ritter, Andre; Wandner, Johannes; Weber, Thomas; Fauler, Alex; Fiederle, Michael; Wong, Winnie S; Campbell, Michael; Meiser, Jan; Meyer, Pascal; Mohr, Jürgen; Michel, Thilo

2014-10-06

The dark-field image obtained in grating-based x-ray phase-contrast imaging can provide information about the objects' microstructures on a scale smaller than the pixel size even with low geometric magnification. In this publication we demonstrate that the dark-field image quality can be enhanced with an energy-resolving pixel detector. Energy-resolved x-ray dark-field images were acquired with a 16-energy-channel photon-counting pixel detector with a 1 mm thick CdTe sensor in a Talbot-Lau x-ray interferometer. A method for contrast-noise-ratio (CNR) enhancement is proposed and validated experimentally. In measurements, a CNR improvement by a factor of 1.14 was obtained. This is equivalent to a possible radiation dose reduction of 23%.

Soft X-ray radiation damage in EM-CCDs used for Resonant Inelastic X-ray Scattering

Science.gov (United States)

Gopinath, D.; Soman, M.; Holland, A.; Keelan, J.; Hall, D.; Holland, K.; Colebrook, D.

2018-02-01

Advancement in synchrotron and free electron laser facilities means that X-ray beams with higher intensity than ever before are being created. The high brilliance of the X-ray beam, as well as the ability to use a range of X-ray energies, means that they can be used in a wide range of applications. One such application is Resonant Inelastic X-ray Scattering (RIXS). RIXS uses the intense and tuneable X-ray beams in order to investigate the electronic structure of materials. The photons are focused onto a sample material and the scattered X-ray beam is diffracted off a high resolution grating to disperse the X-ray energies onto a position sensitive detector. Whilst several factors affect the total system energy resolution, the performance of RIXS experiments can be limited by the spatial resolution of the detector used. Electron-Multiplying CCDs (EM-CCDs) at high gain in combination with centroiding of the photon charge cloud across several detector pixels can lead to sub-pixel spatial resolution of 2-3 μm. X-ray radiation can cause damage to CCDs through ionisation damage resulting in increases in dark current and/or a shift in flat band voltage. Understanding the effect of radiation damage on EM-CCDs is important in order to predict lifetime as well as the change in performance over time. Two CCD-97s were taken to PTB at BESSY II and irradiated with large doses of soft X-rays in order to probe the front and back surfaces of the device. The dark current was shown to decay over time with two different exponential components to it. This paper will discuss the use of EM-CCDs for readout of RIXS spectrometers, and limitations on spatial resolution, together with any limitations on instrument use which may arise from X-ray-induced radiation damage.

Diamond x-ray optics: Transparent, resilient, high-resolution, and wavefront preserving

International Nuclear Information System (INIS)

Shvyd’ko, Yuri; Blank, Vladimir; Terentyev, Sergey

2017-01-01

Diamond features a unique combination of outstanding physical properties perfect for numerous x-ray optics applications, where traditional materials such as silicon fail to perform. In the last two decades, impressive progress has been achieved in synthesizing diamond with high crystalline perfection, in manufacturing efficient, resilient, high-resolution, wavefront-preserving diamond optical components, and in implementing them in cutting-edge x-ray instruments. Diamond optics are essential for tailoring x-rays to the most challenging needs of x-ray research. Furthermore, they are becoming vital for the generation of fully coherent hard x-rays by seeded x-ray free-electron lasers. In this article, we review progress in manufacturing flawless diamond crystal components and their applications in diverse x-ray optical devices, such as x-ray monochromators, beam splitters, high-reflectance backscattering mirrors, lenses, phase plates, diffraction gratings, bent-crystal spectrographs, and windows.

A Three-Year Program of Micro- and Nano-System Technology Development for X-Ray Astronomy

Science.gov (United States)

Canizares, Claude R.

1997-01-01

For many years the work at MIT aimed at the development of new concepts and technologies for space experiments in high-energy astrophysics, but not explicitly supported by flight programs, has been supported. This work has yielded new devices and techniques for X-ray astronomy, primarily low-noise, deep-depletion charge-coupled devices (CCDS) for spectrally-resolved X-ray imaging, and high-performance transmission gratings for high-resolution X-ray spectroscopy. Among the most significant recent achievements have been the development by G. Ricker and associates of the X-ray CCD camera flying on ASCA, and currently in development for AXAF and Astro-E, and the development by C. Canizares and associates of thick, 200 nm-period transmission gratings employing the phenomenon of phase shifting for high-resolution X-ray spectroscopy up to energies of 8- 1 0 keV that is essential for the operation of the AXAF High Energy Transmission Grating Spectrometer (HETGS). Through the current SR&T grant, the latter technology is now being extended successfully to the fabrication of 100 nm-period transmission gratings, which have twice the dispersion of the AXAF gratings. We note that, among other outcomes, the modest investments of past SR&T Grants at MIT resulted in the development of the key technologies for fully one-half of the scientific instrumentation on AXAF. In addition, NASA flight programs that have benefited from previous SR&T support at MIT include the SAS 3 X-ray Observatory, which carried the first rotation modulation collimator, the Focal Plane Crystal Spectrometer (FPCS) on the Einstein Observatory, the CCD cameras on ASCA and planned for Astro-E, the High Energy Transient Experiment (HETE), the Solar EUV Monitor on the Solar and Heliospheric Observatory (SOHO), the Medium Energy Neutral Atom imager (MENA) on the Image for Magnetopause-to-aurora Global Exploration (IMAGE) mission, and the recently-approved Two Wide-Angle Imaging Neutral-atom Spectrometers (TWINS

Arcsecond and Sub-arcsedond Imaging with X-ray Multi-Image Interferometer and Imager for (very) small sattelites

Science.gov (United States)

Hayashida, K.; Kawabata, T.; Nakajima, H.; Inoue, S.; Tsunemi, H.

2017-10-01

The best angular resolution of 0.5 arcsec is realized with the X-ray mirror onborad the Chandra satellite. Nevertheless, further better or comparable resolution is anticipated to be difficult in near future. In fact, the goal of ATHENA telescope is 5 arcsec in the angular resolution. We propose a new type of X-ray interferometer consisting simply of an X-ray absorption grating and an X-ray spectral imaging detector, such as X-ray CCDs or new generation CMOS detectors, by stacking the multi images created with the Talbot interferenece (Hayashida et al. 2016). This system, now we call Multi Image X-ray Interferometer Module (MIXIM) enables arcseconds resolution with very small satellites of 50cm size, and sub-arcseconds resolution with small sattellites. We have performed ground experiments, in which a micro-focus X-ray source, grating with pitch of 4.8μm, and 30 μm pixel detector placed about 1m from the source. We obtained the self-image (interferometirc fringe) of the grating for wide band pass around 10keV. This result corresponds to about 2 arcsec resolution for parrallel beam incidence. The MIXIM is usefull for high angular resolution imaging of relatively bright sources. Search for super massive black holes and resolving AGN torus would be the targets of this system.

New Constraints on the Geometry and Kinematics of Matter Surrounding the Accretion Flow in X-Ray Binaries from Chandra High-energy Transmission Grating X-Ray Spectroscopy

Science.gov (United States)

Tzanavaris, P.; Yaqoob, T.

2018-03-01

The narrow, neutral Fe Kα fluorescence emission line in X-ray binaries (XRBs) is a powerful probe of the geometry, kinematics, and Fe abundance of matter around the accretion flow. In a recent study it has been claimed, using Chandra High-Energy Transmission Grating (HETG) spectra for a sample of XRBs, that the circumnuclear material is consistent with a solar-abundance, uniform, spherical distribution. It was also claimed that the Fe Kα line was unresolved in all cases by the HETG. However, these conclusions were based on ad hoc models that did not attempt to relate the global column density to the Fe Kα line emission. We revisit the sample and test a self-consistent model of a uniform, spherical X-ray reprocessor against HETG spectra from 56 observations of 14 Galactic XRBs. We find that the model is ruled out in 13/14 sources because a variable Fe abundance is required. In two sources a spherical distribution is viable, but with nonsolar Fe abundance. We also applied a solar-abundance Compton-thick reflection model, which can account for the spectra that are inconsistent with a spherical model, but spectra with a broader bandpass are required to better constrain model parameters. We also robustly measured the velocity width of the Fe Kα line and found FWHM values of up to ∼5000 km s‑1. Only in some spectra was the Fe Kα line unresolved by the HETG.

New Constraints on the Geometry and Kinematics of Matter Surrounding the Accretion Flow in X-Ray Binaries from Chandra High-Energy Transmission Grating X-Ray Spectroscopy

Science.gov (United States)

Tzanavaris, P.; Yaqoob, T.

2018-01-01

The narrow, neutral Fe Ka fluorescence emission line in X-ray binaries (XRBs) is a powerful probe of the geometry, kinematics, and Fe abundance of matter around the accretion flow. In a recent study it has been claimed, using Chandra High-Energy Transmission Grating (HETG) spectra for a sample of XRBs, that the circumnuclear material is consistent with a solar-abundance, uniform, spherical distribution. It was also claimed that the Fe Ka line was unresolved in all cases by the HETG. However, these conclusions were based on ad hoc models that did not attempt to relate the global column density to the Fe Ka line emission. We revisit the sample and test a self-consistent model of a uniform, spherical X-ray reprocessor against HETG spectra from 56 observations of 14 Galactic XRBs. We find that the model is ruled out in 13/14 sources because a variable Fe abundance is required. In two sources a spherical distribution is viable, but with nonsolar Fe abundance. We also applied a solar-abundance Compton-thick reflection model, which can account for the spectra that are inconsistent with a spherical model, but spectra with a broader bandpass are required to better constrain model parameters. We also robustly measured the velocity width of the Fe Ka line and found FWHM values of up to approx. 5000 km/s. Only in some spectra was the Fe Ka line unresolved by the HETG.

An ultra-high-vacuum multiple grating chamber and scan drive with improved grating change

International Nuclear Information System (INIS)

Hulbert, S.L.; Holly, D.J.; Middleton, F.H.; Wallace, D.J.; Wisconsin Univ., Stoughton, WI; Wisconsin Univ., Stoughton, WI

1989-01-01

We describe a new grating chamber and scan drive which has been designed, built, and tested by Physical Sciences Laboratory of the University of Wisconsin for the new high flux, high-resolution spectroscopy branch line of the TOK hybrid wiggler/undulator on the NSLS VUV ring. The chamber will contain spherical gratings to be used in the Spherical Grating Monochromator (SGM) configuration introduced by Chen and Sette. The grating chamber houses five 180 mm x 35 mm x 30 mm gratings capable of scanning a range of 12 degree (-14 degree to +8 degree with respect to the incoming beam direction) for VUV and soft X-ray diffraction. The gratings can be switched and precisely indexed while under ultra-high vacuum (UHV) at any scan angle and are mechanically isolated from the vacuum chamber to prevent inaccuracies due to chamber distortions. The gratings can separately be adjusted for height, yaw, pitch, and roll, with the latter three performed while in vacuo. The scan drive provides a resolution of 0.03 arc sec with linearity over the 12 degree range of ∼1.5 arc sec and absolute reproducibility of 1 arc sec. 5 refs., 5 figs

Oxygen, Neon, and Iron X-Ray Absorption in the Local Interstellar Medium

Science.gov (United States)

Gatuzz, Efrain; Garcia, Javier; Kallman, Timothy R.; Mendoza, Claudio

2016-01-01

We present a detailed study of X-ray absorption in the local interstellar medium by analyzing the X-ray spectra of 24 galactic sources obtained with the Chandra High Energy Transmission Grating Spectrometer and the XMM-Newton Reflection Grating Spectrometer. Methods. By modeling the continuum with a simple broken power-law and by implementing the new ISMabs X-ray absorption model, we have estimated the total H, O, Ne, and Fe column densities towards the observed sources. Results. We have determined the absorbing material distribution as a function of source distance and galactic latitude longitude. Conclusions. Direct estimates of the fractions of neutrally, singly, and doubly ionized species of O, Ne, and Fe reveal the dominance of the cold component, thus indicating an overall low degree of ionization. Our results are expected to be sensitive to the model used to describe the continuum in all sources.

Investigation on diagnostic techniques of X-ray radiation characteristic from slit target

International Nuclear Information System (INIS)

Cheng Jinxiu; Miao Wenyong; Sun Kexu; Wang Hongbin; Cao Leifeng; Yang Jiamin; Chen Zhenglin

2001-01-01

On the Xingguang-II facility, X-ray transport process in a cavity target was simulated in a long cylindrical cavity with slits. High temporally and spatially resolved Microchannel Plate (MCP) gated X-ray picosecond frame camera and soft X-ray steak camera were used to investigate the temporal and spatial distribution of the soft X-ray emitted from the cavity wall through the slit. X-ray transport velocity, X-ray emission time and amount of intensity decay was obtained. X-ray CCD pinhole transmission grating spectrometer was used to investigate the spectrum change of the emitted X-ray versus its location. The change characteristic of the spectrum of X-ray absorbed and emitted again and again in transport was obtained. X-ray diodes and Dante spectrometer were used to measure X-ray flux and radiation temperature in the slit, the source and the transport end, respectively. The typical results in the experiment were given. A brief and essential analysis and discussion were made

Highly efficient blazed grating with multilayer coating for tender X-ray energies

NARCIS (Netherlands)

Senf, F.; Bijkerk, Frederik; Eggenstein, F.; Gwalt, G.; Huang, Qiushi; van de Kruijs, Robbert Wilhelmus Elisabeth; Kutz, O.; Lemke, S.; Louis, Eric; Mertin, M.; Packe, I.; Rudolph, I.; Schafers, F.; Siewert, F.; Sokolov, A.; Sturm, Jacobus Marinus; Waberski, C.; Wang, Z.; Wolf, J.; Zeschke, T.; Erko, A.

2016-01-01

For photon energies of 1 – 5 keV, blazed gratings with multilayer coating are ideally suited for the suppression of stray and higher orders light in grating monochromators. We developed and characterized a blazed 2000 lines/mm grating coated with a 20 period Cr/C- multilayer. The multilayer

A combined scanning tunnelling microscope and x-ray interferometer

Science.gov (United States)

Yacoot, Andrew; Kuetgens, Ulrich; Koenders, Ludger; Weimann, Thomas

2001-10-01

A monolithic x-ray interferometer made from silicon and a scanning tunnelling microscope have been combined and used to calibrate grating structures with periodicities of 100 nm or less. The x-ray interferometer is used as a translation stage which moves in discrete steps of 0.192 nm, the lattice spacing of the silicon (220) planes. Hence, movements are traceable to the definition of the metre and the nonlinearity associated with the optical interferometers used to measure displacement in more conventional metrological scanning probe microscopes (MSPMs) removed.

Study on talbot pattern for grating interferometer

Energy Technology Data Exchange (ETDEWEB)

Kim, Young Ju; Oh, Oh Sung; Lee, Seung Wook [Dept. of School of Mechanical Engineering, Pusan National University, Busan (Korea, Republic of); Kim, Jong Yul [Neutron Instrument Division, Korea Atomic Energy Reserch Institute, Daejeon (Korea, Republic of)

2015-04-15

One of properties which X-ray and Neutron can be applied nondestructive test is penetration into the object with interaction leads to decrease in intensity. X-ray interaction with the matter caused by electrons, Neutron caused by atoms. They share applications in nondestructive test area because of their similarities of interaction mechanism. Grating interferometer is the one of applications produces phase contrast image and dark field image. It is defined by Talbot interferometer and Talbot-Lau interferometer according to Talbot effect and Talbot-Lau effect respectively. Talbot interferometer works with coherence beam like X-ray, and Talbot-Lau has an effect with incoherence beam like Neutron. It is important to expect the interference in grating interferometer compared normal nondestructive system. In this paper, simulation works are conducted according to Talbot and Talbot-Lau interferometer in case of X-ray and Neutron. Variation of interference intensity with X-ray and Neutron based on wave theory is constructed and calculate elements consist the system. Additionally, Talbot and Talbot-Lau interferometer is simulated in different kinds of conditions.

Directional x-ray dark-field imaging of strongly ordered systems

Science.gov (United States)

Jensen, Torben Haugaard; Bech, Martin; Zanette, Irene; Weitkamp, Timm; David, Christian; Deyhle, Hans; Rutishauser, Simon; Reznikova, Elena; Mohr, Jürgen; Feidenhans'L, Robert; Pfeiffer, Franz

2010-12-01

Recently a novel grating based x-ray imaging approach called directional x-ray dark-field imaging was introduced. Directional x-ray dark-field imaging yields information about the local texture of structures smaller than the pixel size of the imaging system. In this work we extend the theoretical description and data processing schemes for directional dark-field imaging to strongly scattering systems, which could not be described previously. We develop a simple scattering model to account for these recent observations and subsequently demonstrate the model using experimental data. The experimental data includes directional dark-field images of polypropylene fibers and a human tooth slice.

ON NEUTRAL ABSORPTION AND SPECTRAL EVOLUTION IN X-RAY BINARIES

International Nuclear Information System (INIS)

Miller, J. M.; Cackett, E. M.; Reis, R. C.

2009-01-01

Current X-ray observatories make it possible to follow the evolution of transient and variable X-ray binaries across a broad range in luminosity and source behavior. In such studies, it can be unclear whether evolution in the low-energy portion of the spectrum should be attributed to evolution in the source, or instead to evolution in neutral photoelectric absorption. Dispersive spectrometers make it possible to address this problem. We have analyzed a small but diverse set of X-ray binaries observed with the Chandra High Energy Transmission Grating Spectrometer across a range in luminosity and different spectral states. The column density in individual photoelectric absorption edges remains constant with luminosity, both within and across source spectral states. This finding suggests that absorption in the interstellar medium strongly dominates the neutral column density observed in spectra of X-ray binaries. Consequently, evolution in the low-energy spectrum of X-ray binaries should properly be attributed to evolution in the source spectrum. We discuss our results in the context of X-ray binary spectroscopy with current and future X-ray missions.

An x-ray backlit Talbot-Lau deflectometer for high-energy-density electron density diagnostics

Science.gov (United States)

Valdivia, M. P.; Stutman, D.; Stoeckl, C.; Theobald, W.; Mileham, C.; Begishev, I. A.; Bromage, J.; Regan, S. P.

2016-02-01

X-ray phase-contrast techniques can measure electron density gradients in high-energy-density plasmas through refraction induced phase shifts. An 8 keV Talbot-Lau interferometer consisting of free standing ultrathin gratings was deployed at an ultra-short, high-intensity laser system using K-shell emission from a 1-30 J, 8 ps laser pulse focused on thin Cu foil targets. Grating survival was demonstrated for 30 J, 8 ps laser pulses. The first x-ray deflectometry images obtained under laser backlighting showed up to 25% image contrast and thus enabled detection of electron areal density gradients with a maximum value of 8.1 ± 0.5 × 1023 cm-3 in a low-Z millimeter sized sample. An electron density profile was obtained from refraction measurements with an error of x-ray source-size, similar to conventional radiography.

Analysis of micro-structure in raw and heat treated meat emulsions from multimodal X-ray microtomography

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Nielsen, Mikkel Schou; Miklos, Rikke

2014-01-01

This study presents a novel non-destructive X-ray technique for analyzing meat emulsions before and after heat treatment. The method is based on X-ray grating-interferometry where three complementary imaging modalities are obtained simultaneously measuring the absorption, refraction and scatterin...

Bi-directional x-ray phase-contrast mammography.

Directory of Open Access Journals (Sweden)

Kai Scherer

Full Text Available Phase-contrast x-ray imaging is a promising improvement of conventional absorption-based mammography for early tumor detection. This potential has been demonstrated recently, utilizing structured gratings to obtain differential phase and dark-field scattering images. However, the inherently anisotropic imaging sensitivity of the proposed mono-directional approach yields only insufficient diagnostic information, and has low diagnostic sensitivity to highly oriented structures. To overcome these limitations, we present a two-directional x-ray phase-contrast mammography approach and demonstrate its advantages by applying it to a freshly dissected, cancerous mastectomy breast specimen. We illustrate that the two-directional scanning procedure overcomes the insufficient diagnostic value of a single scan, and reliably detects tumor structures, independently from their orientation within the breast. Our results indicate the indispensable diagnostic necessity and benefit of a multi-directional approach for x-ray phase-contrast mammography.

The Off-plane Grating Rocket Experiment

Science.gov (United States)

Donovan, Benjamin

2018-01-01

The next generation of X-ray spectrometers necessitate significant increases in both resolution and effective area to achieve the science goals set forth in the 2010 Decadal Survey and the 2013 Astrophysics Roadmap. The Off-plane Grating Rocket Experiment (OGRE), an X-ray spectroscopy suborbital rocket payload currently scheduled for launch in Q3 2020, will serve as a testbed for several key technologies which can help achieve the desired performance increases of future spectrometers. OGRE will be the first instrument to fly mono-crystalline silicon X-ray mirrors developed at NASA Goddard Space Flight Center. The payload will also utilize an array of off-plane gratings manufactured at The Pennsylvania State University. Additionally, the focal plane will be populated with an array of four electron-multiplying CCDs developed by the Open University and XCAM Ltd. With these key technologies, OGRE hopes to achieve the highest resolution on-sky soft X-ray spectrum to date. We discuss the optical design, expected performance, and the current status of the payload.

Line spread functions of blazed off-plane gratings operated in the Littrow mounting

Science.gov (United States)

DeRoo, Casey T.; McEntaffer, Randall L.; Miles, Drew M.; Peterson, Thomas J.; Marlowe, Hannah; Tutt, James H.; Donovan, Benjamin D.; Menz, Benedikt; Burwitz, Vadim; Hartner, Gisela; Allured, Ryan; Smith, Randall K.; Günther, Ramses; Yanson, Alex; Vacanti, Giuseppe; Ackermann, Marcelo

2016-04-01

Future soft x-ray (10 to 50 Å) spectroscopy missions require higher effective areas and resolutions to perform critical science that cannot be done by instruments on current missions. An x-ray grating spectrometer employing off-plane reflection gratings would be capable of meeting these performance criteria. Off-plane gratings with blazed groove facets operating in the Littrow mounting can be used to achieve excellent throughput into orders achieving high resolutions. We have fabricated two off-plane gratings with blazed groove profiles via a technique that uses commonly available microfabrication processes, is easily scaled for mass production, and yields gratings customized for a given mission architecture. Both fabricated gratings were tested in the Littrow mounting at the Max Planck Institute for Extraterrestrial Physics (MPE) PANTER x-ray test facility to assess their performance. The line spread functions of diffracted orders were measured, and a maximum resolution of 800±20 is reported. In addition, we also observe evidence of a blaze effect from measurements of relative efficiencies of the diffracted orders.

Advances in indirect detector systems for ultra high-speed hard X-ray imaging with synchrotron light

Science.gov (United States)

Olbinado, M. P.; Grenzer, J.; Pradel, P.; De Resseguier, T.; Vagovic, P.; Zdora, M.-C.; Guzenko, V. A.; David, C.; Rack, A.

2018-04-01

We report on indirect X-ray detector systems for various full-field, ultra high-speed X-ray imaging methodologies, such as X-ray phase-contrast radiography, diffraction topography, grating interferometry and speckle-based imaging performed at the hard X-ray imaging beamline ID19 of the European Synchrotron—ESRF. Our work highlights the versatility of indirect X-ray detectors to multiple goals such as single synchrotron pulse isolation, multiple-frame recording up to millions frames per second, high efficiency, and high spatial resolution. Besides the technical advancements, potential applications are briefly introduced and discussed.

Mechanical design aspects of a soft X-ray plane grating monochromator

CERN Document Server

Vasina, R; Dolezel, P; Mynar, M; Vondracek, M; Chab, V; Slezak, J A; Comicioli, C; Prince, K C

2001-01-01

A plane grating monochromator based on the SX-700 concept has been constructed for the Materials Science Beamline, Elettra, which is attached to a bending magnet. The tuning range is from 35 to 800 eV with calculated spectral resolving power epsilon/DELTA epsilon better than 4000 in the whole range. The optical elements consist of a toroidal prefocusing mirror, polarization aperture, entrance slit, plane pre-mirror, single plane grating (blazed), spherical mirror, exit slit and toroidal refocusing mirror. The plane grating is operated in the fixed focus mode with C sub f sub f =2.4. Energy scanning is performed by rotation of the plane grating and simultaneous translation and rotation of the plane pre-mirror. A novel solution is applied for the motion of the plane pre-mirror, namely by a translation and mechanically coupling the rotation by a cam. The slits have no moving parts in vacuum to reduce cost and increase ruggedness, and can be fully closed without risk of damage. In the first tests, a resolving pow...

A ``perfect'' Late Phase Flare Loop: X-ray And Radio Studies

Science.gov (United States)

Bain, Hazel; Fletcher, L.

2009-05-01

We present observations of a GOES X3.1 class flare which occurred on the 24th August 2002. The event was observed by a number of instruments including RHESSI, TRACE and NoRH. This flare is particularly interesting due to its position and orientation on the west limb of the Sun. The flare appears to be perpendicular to the line of sight making it possible to ascertain the geometrical parameters of the post flare arcade loops. We investigate the decay phase of the flare by comparing X-ray and radio observations of the post flare arcade loops with models of soft x-ray and thermal gyrosynchrotron emission to characterise the electron distribution present within the loop. HMB gratefully acknowledges the support of an SPD and STFC studentship. LF gratefully acknowledges the support of an STFC Rolling Grant, and financial support by the European Commission through the SOLAIRE Network (MTRN-CT_2006-035484)

X-Ray Fluorescence Spectrometry. II. Determination of Uranium in ores

International Nuclear Information System (INIS)

Bermudez Polonio, J.; Crus Castillo, F. de la; Fernandez Cellini, R.

1961-01-01

A method of analysis of uranium in ores by X-ray spectrometry was developed, using the internal standard technique. Strontium was found to be the most suitable internal standard for general use. A Norelco Philips X-ray fluorescent spectrometer was used in this work, equipped with a lithium fluoride crystal acting as a diffraction grating analyzer. The intensity of the uranium-L α 1 spectral line is calculated and related to corresponding strontium-K α spectral line, both detected with a Scintillation Counter. (Author) 31 refs

X-ray quality assessment by MTF analysis

International Nuclear Information System (INIS)

Gais, P.; Burger, G.; Drexler, G.; Rappl, M.; Bunde, E.; Lissner, J.; Schaetzl, M.

1985-01-01

In a previous study a lucite phantom with several physical elements embedded, such as lead gratings with varying line widths, etc., was exposed at 200 X-ray installations in Bavaria, Federal Republic of Germany, by a conventional diagnostic standard technique. One of the parameters investigated was the local resolution achieved, determined visually by examination of the grating images. The same radiographs have now been used in a retrospective comparative study, based upon a quantitative analysis of TV images of the films. The films were positioned on a commercial illuminator screen and looked at by a TV camera through a simple magnifying optical system. The video signals were digitised, resulting in a pixel distance of 50 μm. In a first approach the edges of the broad frames of the lead gratings were adjusted vertically and the normalised sum of all 256 TV scanning lines taken as the edge function f(x). This was differentiated and suitably Fourier-transformed, delivering the modulation transfer function (MTF). The MTF can be analysed in several ways to describe quantitatively the maximum local resolution achievable. Correlation of some frequency measurements with the visually determined line resolution is generally good. (author)

Low-Energy Microfocus X-Ray Source for Enhanced Testing Capability in the Stray Light Facility

Science.gov (United States)

Gaskin, Jessica; O'Dell, Stephen; Kolodziejczak, Jeff

2015-01-01

Research toward high-resolution, soft x-ray optics (mirrors and gratings) necessary for the next generation large x-ray observatories requires x-ray testing using a low-energy x-ray source with fine angular size (energy microfocus (approximately 0.1 mm spot) x-ray source from TruFocus Corporation that mates directly to the Stray Light Facility (SLF). MSFC X-ray Astronomy team members are internationally recognized for their expertise in the development, fabrication, and testing of grazing-incidence optics for x-ray telescopes. One of the key MSFC facilities for testing novel x-ray instrumentation is the SLF. This facility is an approximately 100-m-long beam line equipped with multiple x-ray sources and detectors. This new source adds to the already robust compliment of instrumentation, allowing MSFC to support additional internal and community x-ray testing needs.

LCLS in—photon out: fluorescence measurement of neon using soft x-rays

Science.gov (United States)

Obaid, Razib; Buth, Christian; Dakovski, Georgi L.; Beerwerth, Randolf; Holmes, Michael; Aldrich, Jeff; Lin, Ming-Fu; Minitti, Michael; Osipov, Timur; Schlotter, William; Cederbaum, Lorenz S.; Fritzsche, Stephan; Berrah, Nora

2018-02-01

We measured the fluorescence photon yield of neon upon soft x-ray ionization (∼1200 eV) from the x-ray free-electron laser at Linac Coherent Light Source, and demonstrated the usage of a grazing incidence spectrometer with a variable line spacing grating to perform x-ray fluorescence spectroscopy on a gas phase system. Our measurements also allowed us to estimate the focal size of the beam from the theoretical description developed, in terms of the rate equation approximation accounting for photoionization shake off of neutral neon and double auger decay of single core holes.

Grating-based X-ray Dark-field Computed Tomography of Living Mice.

Science.gov (United States)

Velroyen, A; Yaroshenko, A; Hahn, D; Fehringer, A; Tapfer, A; Müller, M; Noël, P B; Pauwels, B; Sasov, A; Yildirim, A Ö; Eickelberg, O; Hellbach, K; Auweter, S D; Meinel, F G; Reiser, M F; Bech, M; Pfeiffer, F

2015-10-01

Changes in x-ray attenuating tissue caused by lung disorders like emphysema or fibrosis are subtle and thus only resolved by high-resolution computed tomography (CT). The structural reorganization, however, is of strong influence for lung function. Dark-field CT (DFCT), based on small-angle scattering of x-rays, reveals such structural changes even at resolutions coarser than the pulmonary network and thus provides access to their anatomical distribution. In this proof-of-concept study we present x-ray in vivo DFCTs of lungs of a healthy, an emphysematous and a fibrotic mouse. The tomographies show excellent depiction of the distribution of structural - and thus indirectly functional - changes in lung parenchyma, on single-modality slices in dark field as well as on multimodal fusion images. Therefore, we anticipate numerous applications of DFCT in diagnostic lung imaging. We introduce a scatter-based Hounsfield Unit (sHU) scale to facilitate comparability of scans. In this newly defined sHU scale, the pathophysiological changes by emphysema and fibrosis cause a shift towards lower numbers, compared to healthy lung tissue.

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.

Performance testing of an off-plane reflection grating and silicon pore optic spectrograph at PANTER

Science.gov (United States)

Marlowe, Hannah; McEntaffer, Randall L.; Allured, Ryan; DeRoo, Casey T.; Donovan, Benjamin D.; Miles, Drew M.; Tutt, James H.; Burwitz, Vadim; Menz, Benedikt; Hartner, Gisela D.; Smith, Randall K.; Cheimets, Peter; Hertz, Edward; Bookbinder, Jay A.; Günther, Ramses; Yanson, Alex; Vacanti, Giuseppe; Ackermann, Marcelo

2015-10-01

An x-ray spectrograph consisting of aligned, radially ruled off-plane reflection gratings and silicon pore optics (SPO) was tested at the Max Planck Institute for Extraterrestrial Physics PANTER x-ray test facility. SPO is a test module for the proposed Arcus mission, which will also feature aligned off-plane reflection gratings. This test is the first time two off-plane gratings were actively aligned to each other and with an SPO to produce an overlapped spectrum. We report the performance of the complete spectrograph utilizing the aligned gratings module and plans for future development.

Phase-contrast imaging and tomography at 60 keV using a conventional x-ray tube source

International Nuclear Information System (INIS)

Donath, Tilman; Bunk, Oliver; Groot, Waldemar; Bednarzik, Martin; Gruenzweig, Christian; David, Christian; Pfeiffer, Franz; Hempel, Eckhard; Popescu, Stefan; Hoheisel, Martin

2009-01-01

Phase-contrast imaging at laboratory-based x-ray sources using grating interferometers has been developed over the last few years for x-ray energies of up to 28 keV. Here, we show first phase-contrast projection and tomographic images recorded at significantly higher x-ray energies, produced by an x-ray tube source operated at 100 kV acceleration voltage. We find our measured tomographic phase images in good agreement with tabulated data. The extension of phase-contrast imaging to this significantly higher x-ray energy opens up many applications of the technique in medicine and industrial nondestructive testing.

The X-ray microscopy project at saga SLS

International Nuclear Information System (INIS)

Yasumoto, M.; Ishiguro, E.; Takemoto, K.; Kihara, H.; Kamijo, N.; Tomimasu, T.; Tsurushima, T.; Takahara, A.; Hara, K.; Chikaura, Y.

2002-01-01

A new high resolution X-ray microscopy project has been proposed at Saga synchrotron light source, which is a third generation synchrotron light facility in Japan. Two microscopy beamlines are planned for this project. One is a scanning microscope in the water window region, and the other is a full-field imaging microscope in the multi-keV X-ray energy region. To demonstrate the feasibility of the project, the optical layout of the scanning microscope was designed. The beamline mainly consists of a 3.5 cm periodical undulator, a varied line-spacing plane grating monochromator (600 lines/mm) and an end-station including a zone plate. Thus, the calculated X-ray properties focused on the sample position are as follows: the spot size is ∼ 70 nm, the monochromaticity is ∼2000, and the photon flux is 10 9 ∼ 10 10 photons/sec. (authors)

Linac Coherent Light Source soft x-ray materials science instrument optical design and monochromator commissioning

Czech Academy of Sciences Publication Activity Database

Heimann, P.; Krupin, O.; Schlotter, W.F.; Turner, J.; Krzywinski, J.; Sorgenfrei, F.; Messerschmidt, M.; Bernstein, D.; Chalupský, Jaromír; Hájková, Věra; Hau-Riege, S.; Holmes, M.; Juha, Libor; Kelez, N.; Lüning, J.; Nordlund, D.; Perea, M.F.; Scherz, A.; Soufli, R.; Wurth, W.; Rowen, M.

2011-01-01

Roč. 82, č. 9 (2011), 093104/1-093104/8 ISSN 0034-6748 R&D Projects: GA MŠk(CZ) ME10046 Institutional research plan: CEZ:AV0Z10100523 Keywords : diffraction gratings * light sources * linear accelerators * optical materials * x-ray monochromators * x-ray optics Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.367, year: 2011

X-Ray Absorption Near-Edge Structure (XANES) of Calcium L3,2 Edges of Various Calcium Compounds and X-Ray Excited Optical Luminescence (XEOL) Studies of Luminescent Calcium Compounds

International Nuclear Information System (INIS)

Ko, J. Y. Peter; Zhou Xingtai; Sham, T.-K.; Heigl, Franziskus; Regier, Tom; Blyth, Robert

2007-01-01

X-ray absorption at calcium L3,2 edges of various calcium compounds were measured using a high resolution Spherical Grating Monochromator (SGM) at the Canadian Light Source (CLS). We observe that each compound has its unique fine structure of L3,2 edges. This uniqueness is due to differences in local structure of compounds. We also performed (X-ray Excited Optical Luminescence) XEOL of selected luminescent calcium compounds to investigate their optical properties. XEOL is a photon-in-photon-out technique in which the optical luminescence that is excited by tunable x-rays from a synchrotron light source is monitored. Depending on excitation energy of the x-ray, relative intensities of luminescence peaks vary. Recent findings of the results will be presented here

Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula

Science.gov (United States)

Weisskopf, Martin C.; Hester, J. Jeff; Tennant, Allyn F.; Elsner, Ronald F.; Schulz, Norbert S.; Marshall, Herman L.; Karovska, Margarita; Nichols, Joy S.; Swartz, Douglas A.; Kolodziejczak, Jeffery J.

2000-01-01

The Chandra X-Ray Observatory observed the Crab Nebula and pulsar during orbital calibration. Zeroth-order images with the High-Energy Transmission Grating (HETG) readout by the Advanced Charge Coupled Devices (CCD) Imaging Spectrometer spectroscopy array (ACIS-S) show a striking richness of X-ray structure at a resolution comparable to that of the best ground-based visible-light observations. The HETG-ACIS-S images reveal, for the first time, an X-ray inner ring within the X-ray torus, the suggestion of a hollow-tube structure for the torus, and X-ray knots along the inner ring and (perhaps) along the inward extension of the X-ray jet. Although complicated by instrumental effects and the brightness of the Crab Nebula, the spectrometric analysis shows systematic variations of the X-ray spectrum throughout the nebula.

Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula.

Science.gov (United States)

Weisskopf; Hester; Tennant; Elsner; Schulz; Marshall; Karovska; Nichols; Swartz; Kolodziejczak; O'Dell

2000-06-20

The Chandra X-Ray Observatory observed the Crab Nebula and pulsar during orbital calibration. Zeroth-order images with the High-Energy Transmission Grating (HETG) readout by the Advanced CCD Imaging Spectrometer spectroscopy array (ACIS-S) show a striking richness of X-ray structure at a resolution comparable to that of the best ground-based visible-light observations. The HETG-ACIS-S images reveal, for the first time, an X-ray inner ring within the X-ray torus, the suggestion of a hollow-tube structure for the torus, and X-ray knots along the inner ring and (perhaps) along the inward extension of the X-ray jet. Although complicated by instrumental effects and the brightness of the Crab Nebula, the spectrometric analysis shows systematic variations of the X-ray spectrum throughout the nebula.

X-ray directional dark-field contrast for sub-pixel resolution imaging of bone microstructures

Energy Technology Data Exchange (ETDEWEB)

Biernath, Thomas; Malecki, Andreas; Potdevin, Guillaume; Bech, Martin; Pfeiffer, Franz [Department of Physics (E17) and Institute of Medical Engineering (IMETUM), Technische Universitaet Muenchen (Germany); Jensen, Torben [Niels Bohr Institute, University of Copenhagen (Denmark)

2011-07-01

The basic principles of X-ray image formation in radiography have remained essentially unchanged since Roentgen first discovered X-rays over a hundred years ago. The conventional approach relies on X-ray absorption as the sole source of contrast and thus gives an information about the density changes in the sample. The recently introduced X-ray dark field imaging technique (DFI) yields a fundamentally different signal: DFI is a measure of the sample small angle scattering signal and thus yields information about the sample microstructure. Such measurements can be effectively performed thanks to a Laue-Talbot grating interferometer. This presentation shows recent experimental directional dark-field imaging results of various samples both from synchrotron and classical X-ray tube sources.

High-energy synchrotron X-ray radiography of shock-compressed materials

Science.gov (United States)

Rutherford, Michael E.; Chapman, David J.; Collinson, Mark A.; Jones, David R.; Music, Jasmina; Stafford, Samuel J. P.; Tear, Gareth R.; White, Thomas G.; Winters, John B. R.; Drakopoulos, Michael; Eakins, Daniel E.

2015-06-01

This presentation will discuss the development and application of a high-energy (50 to 250 keV) synchrotron X-ray imaging method to study shock-compressed, high-Z samples at Beamline I12 at the Diamond Light Source synchrotron (Rutherford-Appleton Laboratory, UK). Shock waves are driven into materials using a portable, single-stage gas gun designed by the Institute of Shock Physics. Following plate impact, material deformation is probed in-situ by white-beam X-ray radiography and complimentary velocimetry diagnostics. The high energies, large beam size (13 x 13 mm), and appreciable sample volumes (~ 1 cm3) viable for study at Beamline I12 compliment existing in-house pulsed X-ray capabilities and studies at the Dynamic Compression Sector. The authors gratefully acknowledge the ongoing support of Imperial College London, EPSRC, STFC and the Diamond Light Source, and AWE Plc.

Soft x-ray microscope using Fourier transform holography

International Nuclear Information System (INIS)

McNulty, I.; Kirz, J.; Jacobsen, C.; Anderson, E.; Howells, M.R.; Rarback, H.

1989-01-01

A Fourier transform holographic microscope with an anticipated resolution of better than 100 nm has been built. Extensive testing of the apparatus has begun. Preliminary results include the recording of interference fringes using 3.6 nm x-rays. The microscope employs a charge-coupled device (CCD) detector array of 576 x 384 elements. The system is illuminated by soft x-rays from a high brightness undulator. The reference point source is formed by a Fresnel zone plate with a finest outer zone width of 50 nm. Sufficient temporal coherence for hologram formation is obtained by a spherical grating monochromator. The x-ray hologram intensities at the recording plane are to be collected, digitized and reconstructed by computer. Data acquisition is under CAMAC control, while image display and off-line processing takes place on a VAX graphics workstation. Computational models of Fourier transform hologram synthesis, and reconstruction in the presence of noise, have demonstrated the feasibility of numerical methods in two dimensions, and that three-dimensional information is potentially recoverable. 13 refs., 3 figs

Role of the Chandra X-Ray Observatory Observations for the Study of Ionized Plasmas

Science.gov (United States)

Weisskopf, Martin C.

2010-01-01

The Chandra X-Ray Observatory, launched in 1999, is now beginning its 12-th year of operation. Chandra, the X-ray component of NASA s Great Observatory program, continues to operate efficiently, somewhat remarkable considering that the Observatory was designed for three years of operation with a goal of five. The Observatory features X-ray optics with sub-arcsecond angular resolution and a small suite of instruments, including transmission gratings, which allow for high-resolution spectroscopy of point sources. We will detail the capabilities of the Observatory for making such spectroscopic measurements and discuss a number of examples of what has been learned about the astrophysical plasmas capable of producing bright X-ray emission.

Performance testing of a novel off-plane reflection grating and silicon pore optic spectrograph at PANTER

Science.gov (United States)

Marlowe, Hannah; McEntaffer, Randall L.; Allured, Ryan; DeRoo, Casey; Miles, Drew M.; Donovan, Benjamin D.; Tutt, James H.; Burwitz, Vadim; Menz, Benedikt; Hartner, Gisela D.; Smith, Randall K.; Günther, Ramses; Yanson, Alex; Vacanti, Giuseppe; Ackermann, Marcelo

2015-05-01

An X-ray spectrograph consisting of aligned, radially ruled off-plane reflection gratings and silicon pore optics (SPO) was tested at the Max Planck Institute for extraterrestrial Physics PANTER X-ray test facility. The SPO is a test module for the proposed Arcus mission, which will also feature aligned off-plane reflection gratings. This test is the first time two off-plane gratings were actively aligned to each other and with a SPO to produce an overlapped spectrum. We report the performance of the complete spectrograph utilizing the aligned gratings module and plans for future development.

Soft x-ray spectroscopy undulator beamline at the Advanced Photon Source

Energy Technology Data Exchange (ETDEWEB)

Randall, K.J.; Xu, Z.; Moore, J.F.; Gluskin, E.

1997-09-01

Construction of the high-resolution soft x ray spectroscopy undulator beamline, 2ID-C, at the Advanced Photon Source (APS) has been completed. The beamline, one of two soft x ray beamlines at the APS, will cover the photon energy range from 500 to 3,000 eV, with a maximum resolving power between 7,000 and 14,000. The optical design is based on a spherical grating monochromator (SGM) giving both high resolution and high flux throughput. Photon flux is calculated to be approximately 10{sup 12}--10{sup 13} photons per second with a beam size of approximately 1 x 1 mm{sup 2} at the sample.

Short-wavelength soft-x-ray laser pumped in double-pulse single-beam non-normal incidence

International Nuclear Information System (INIS)

Zimmer, D.; Ros, D.; Guilbaud, O.; Habib, J.; Kazamias, S.; Zielbauer, B.; Bagnoud, V.; Ecker, B.; Aurand, B.; Kuehl, T.; Hochhaus, D. C.; Neumayer, P.

2010-01-01

We demonstrated a 7.36 nm Ni-like samarium soft-x-ray laser, pumped by 36 J of a neodymium:glass chirped-pulse amplification laser. Double-pulse single-beam non-normal-incidence pumping was applied for efficient soft-x-ray laser generation. In this case, the applied technique included a single-optic focusing geometry for large beam diameters, a single-pass grating compressor, traveling-wave tuning capability, and an optimized high-energy laser double pulse. This scheme has the potential for even shorter-wavelength soft-x-ray laser pumping.

Development of an x-ray Talbot-Lau moire deflectometer for fast density profile measurements of dense plasmas generated by beam-target interactions

Energy Technology Data Exchange (ETDEWEB)

Clayton, Dan [National Security Technol., LLC, Los Alamos, NM (United States); Berninger, M; Meidinger, A; Stutman, Dan; Valdivia, Maria Pia

2015-05-01

For the first time an x-ray Talbot-Lau moire deflectometer is being developed that will use a flash tube source and fast detector for dynamic density gradient measurements. In Talbot-Lau moire deflectometry, an x-ray grating makes an image of itself on a second grating (the Talbot effect) to produce a moire pattern on a detector. The test object is placed between these gratings, with variations in index of refraction changing the pattern. A third grating in front of an incoherent x-ray source produces an array of coherent sources. With a 150 kV x-ray flash tube as the source, the gratings are placed in a glancing angle setup for performance at ~60 keV. The detector is a gated CCD with a fast scintillator for x-ray conversion. This diagnostic, designed for the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT) at Los Alamos National Laboratory, measures the density profile of dense plasma plumes ejected from beam-target interactions. DARHT has two high-current, pulsed, inductive linear electron accelerators with bremsstrahlung targets at the end of each beam line to create 2-D radiographic images of hydrodynamic tests. One multi-pulse accelerator has up to four beam pulses striking the same target within 2 μs. Computer simulations that model target evolution and ejected material between pulses are used to design these targets for optimal radiographic performance; the x-ray deflectometer will directly measure density gradients in the ejected plumes and provide the first experimental constraints to these models. During the first year, currently underway, the diagnostic systems are being designed. In year two, the flash tube and fast detector will be deployed at DARHT for radiographic imaging while the deflectometer is built and tested on the bench with a continuous source. Finally, in year three, the fast deflectometer will be installed on DARHT and density measurements will be performed.

Direct intensity calibration of X-ray grazing-incidence microscopes with home-lab source

Science.gov (United States)

Li, Yaran; Xie, Qing; Chen, Zhiqiang; Xin, Qiuqi; Wang, Xin; Mu, Baozhong; Wang, Zhanshan; Liu, Shenye; Ding, Yongkun

2018-01-01

Direct intensity calibration of X-ray grazing-incidence microscopes is urgently needed in quantitative studies of X-ray emission from laser plasma sources in inertial confinement fusion. The existing calibration methods for single reflecting mirrors, crystals, gratings, filters, and X-ray detectors are not applicable for such X-ray microscopes due to the specific optical structure and the restrictions of object-image relation. This article presents a reliable and efficient method that can be performed using a divergent X-ray source and an energy dispersive Si-PIN (silicon positive-intrinsic-negative) detector in an ordinary X-ray laboratory. The transmission theory of X-ray flux in imaging diagnostics is introduced, and the quantities to be measured are defined. The calibration method is verified by a W/Si multilayer-coated Kirkpatrick-Baez microscope with a field of view of ˜95 μm at 17.48 keV. The mirror reflectance curve in the 1D coordinate is drawn with a peak value of 20.9% and an uncertainty of ˜6.0%.

Optical technologies for extreme-ultraviolet and soft X-ray coherent sources

International Nuclear Information System (INIS)

Canova, Federico; Poletto, Luca

2015-01-01

The book reviews the most recent achievements in optical technologies for XUV and X-ray coherent sources. Particular attention is given to free-electron-laser facilities, but also to other sources available at present, such as synchrotrons, high-order laser harmonics and X-ray lasers. The optical technologies relevant to each type of source are discussed. In addition, the main technologies used for photon handling and conditioning, namely multilayer mirrors, adaptive optics, crystals and gratings are explained. Experiments using coherent light received during the last decades a lot of attention for the X-ray regime. Strong efforts were taken for the realization of almost fully coherent sources, e.g. the free-electron lasers, both as independent sources in the femtosecond and attosecond regimes and as seeding sources for free-electron-lasers and X-ray gas lasers. In parallel to the development of sources, optical technologies for photon handling and conditioning of such coherent and intense X-ray beams advanced. New problems were faced for the realization of optical components of beamlines demanding to manage coherent X-ray photons, e.g. the preservation of coherence and time structure of ultra short pulses.

X-ray Optics for BES Light Source Facilities

Energy Technology Data Exchange (ETDEWEB)

Mills, Dennis [Argonne National Lab. (ANL), Argonne, IL (United States); Padmore, Howard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lessner, Eliane [Dept. of Energy (DOE), Washington DC (United States). Office of Science

2013-03-27

potentially revolutionary science involves soft excitations such as magnons and phonons; in general, these are well below the resolution that can be probed by today’s optical systems. The study of these low-energy excitations will only move forward if advances are made in high-resolution gratings for the soft X-ray energy region, and higher-resolution crystal analyzers for the hard X-ray region. In almost all the forefront areas of X-ray science today, the main limitation is our ability to focus, monochromate, and manipulate X-rays at the level required for these advanced measurements. To address these issues, the U.S. Department of Energy (DOE) Office of Basic Energy Sciences (BES) sponsored a workshop, X-ray Optics for BES Light Source Facilities, which was held March 27–29, 2013, near Washington, D.C. The workshop addressed a wide range of technical and organizational issues. Eleven working groups were formed in advance of the meeting and sought over several months to define the most pressing problems and emerging opportunities and to propose the best routes forward for a focused R&D program to solve these problems. The workshop participants identified eight principal research directions (PRDs), as follows: Development of advanced grating lithography and manufacturing for high-energy resolution techniques such as soft X-ray inelastic scattering. Development of higher-precision mirrors for brightness preservation through the use of advanced metrology in manufacturing, improvements in manufacturing techniques, and in mechanical mounting and cooling. Development of higher-accuracy optical metrology that can be used in manufacturing, verification, and testing of optomechanical systems, as well as at wavelength metrology that can be used for quantification of individual optics and alignment and testing of beamlines. Development of an integrated optical modeling and design framework that is designed and maintained specifically for X-ray optics. Development of

X-ray Optics for BES Light Source Facilities

International Nuclear Information System (INIS)

Mills, Dennis; Padmore, Howard; Lessner, Eliane

2013-01-01

and potentially revolutionary science involves soft excitations such as magnons and phonons; in general, these are well below the resolution that can be probed by today's optical systems. The study of these low-energy excitations will only move forward if advances are made in high-resolution gratings for the soft X-ray energy region, and higher-resolution crystal analyzers for the hard X-ray region. In almost all the forefront areas of X-ray science today, the main limitation is our ability to focus, monochromate, and manipulate X-rays at the level required for these advanced measurements. To address these issues, the U.S. Department of Energy (DOE) Office of Basic Energy Sciences (BES) sponsored a workshop, X-ray Optics for BES Light Source Facilities, which was held March 27-29, 2013, near Washington, D.C. The workshop addressed a wide range of technical and organizational issues. Eleven working groups were formed in advance of the meeting and sought over several months to define the most pressing problems and emerging opportunities and to propose the best routes forward for a focused R&D program to solve these problems. The workshop participants identified eight principal research directions (PRDs), as follows: Development of advanced grating lithography and manufacturing for high-energy resolution techniques such as soft X-ray inelastic scattering. Development of higher-precision mirrors for brightness preservation through the use of advanced metrology in manufacturing, improvements in manufacturing techniques, and in mechanical mounting and cooling. Development of higher-accuracy optical metrology that can be used in manufacturing, verification, and testing of optomechanical systems, as well as at wavelength metrology that can be used for quantification of individual optics and alignment and testing of beamlines. Development of an integrated optical modeling and design framework that is designed and maintained specifically for X-ray optics. Development of

Synchrotron hard X-ray imaging of shock-compressed metal powders

Science.gov (United States)

Rutherford, Michael E.; Chapman, David J.; Collinson, Mark A.; Jones, David R.; Music, Jasmina; Stafford, Samuel J. P.; Tear, Gareth R.; White, Thomas G.; Winters, John B. R.; Drakopoulos, Michael; Eakins, Daniel E.

2015-06-01

This poster will present the application of a new, high-energy (50 to 250 keV) synchrotron X-ray radiography technique to the study of shock-compressed granular materials. Following plate-impact loading, transmission radiography was used to quantitatively observe the compaction and release processes in a range of high-Z metal powders (e.g. Fe, Ni, Cu). By comparing the predictions of 3D numerical models initialized from X-ray tomograms-captured prior to loading-with experimental results, this research represents a new approach to refining mesoscopic compaction models. The authors gratefully acknowledge the ongoing support of Imperial College London, EPSRC, STFC and the Diamond Light Source, and AWE Plc.

The Wide Field Imager of the International X-ray Observatory

Energy Technology Data Exchange (ETDEWEB)

Stefanescu, A., E-mail: astefan@hll.mpg.d [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Johannes Gutenberg-Universitaet, Inst. f. anorganische und analytische Chemie, 55099 Mainz (Germany); Bautz, M.W. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Burrows, D.N. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Bombelli, L.; Fiorini, C. [Politecnico di Milano, Dipartimento di Elettronica e Informazione, Milano (Italy); INFN Sezione di Milano, Milano (Italy); Fraser, G. [Space Research Centre, Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Heinzinger, K. [PNSensor GmbH, Roemerstr. 28, 80803 Muenchen (Germany); Herrmann, S. [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstr., 85748 Garching (Germany); Kuster, M. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Schlossgartenstr. 9, 64289 Darmstadt (Germany); Lauf, T. [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstr., 85748 Garching (Germany); Lechner, P. [PNSensor GmbH, Roemerstr. 28, 80803 Muenchen (Germany); Lutz, G. [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Max-Planck-Institut fuer Physik, Foehringer Ring 6, 80805 Muenchen (Germany); Majewski, P. [PNSensor GmbH, Roemerstr. 28, 80803 Muenchen (Germany); Meuris, A. [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstr., 85748 Garching (Germany); Murray, S.S. [Harvard/Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

2010-12-11

The International X-ray Observatory (IXO) will be a joint X-ray observatory mission by ESA, NASA and JAXA. It will have a large effective area (3 m{sup 2} at 1.25 keV) grazing incidence mirror system with good angular resolution (5 arcsec at 0.1-10 keV) and will feature a comprehensive suite of scientific instruments: an X-ray Microcalorimeter Spectrometer, a High Time Resolution Spectrometer, an X-ray Polarimeter, an X-ray Grating Spectrometer, a Hard X-ray Imager and a Wide-Field Imager. The Wide Field Imager (WFI) has a field-of-view of 18 ftx18 ft. It will be sensitive between 0.1 and 15 keV, offer the full angular resolution of the mirrors and good energy resolution. The WFI will be implemented as a 6 in. wafer-scale monolithical array of 1024x1024 pixels of 100x100{mu}m{sup 2} size. The DEpleted P-channel Field-Effect Transistors (DEPFET) forming the individual pixels are devices combining the functionalities of both detector and amplifier. Signal electrons are collected in a potential well below the transistor's gate, modulating the transistor current. Even when the device is powered off, the signal charge is collected and kept in the potential well below the gate until it is explicitly cleared. This makes flexible and fast readout modes possible.

Discovery of X-Ray Emission from the Crab Pulsar at Pulse Minimum

Science.gov (United States)

Tennant, Allyn F.; Becker, Werner; Juda, Michael; Elsner, Ronald F.; Kolodziejczak, Jeffery J.; Murray, Stephen S.; ODell, Stephen L.; Paerels, Frits; Swartz, Douglas A.

2001-01-01

The Chandra X-Ray Observatory observed the Crab pulsar using the Low-Energy Transmission Grating with the High-Resolution Camera. Time-resolved zeroth-order images reveal that the pulsar emits X-rays at all pulse phases. Analysis of the flux at minimum - most likely non-thermal in origin - places an upper limit (T(sub infinity) < 2.1 MK) on the surface temperature of the underlying neutron star. In addition, analysis of the pulse profile establishes that the error in the Chandra-determined absolute time is quite small, -0.2 +/- 0.1 ms.

Rockets for Extended Source Soft X-ray Spectroscopy

Science.gov (United States)

McEntaffer, Randall

The soft X-ray background surrounds our local galactic environment yet very little is known about the physical characteristics of this plasma. A high-resolution spectrum could unlock the properties of this million degree gas but the diffuse, low intensity nature of the background have made it difficult to observe, especially with a dispersive spectrograph. Previous observations have relied on X-ray detector energy resolution which produces poorly defined spectra that are poorly fit by complex plasma models. Here we propose a series of suborbital rocket flights that will begin the characterization of this elusive source through high-resolution X-ray grating spectroscopy. The rocket-based spectrograph can resolve individual emission lines over the soft X-ray band and place tight constraints on the temperature, density, abundance, ionization state and age of the plasma. These payloads will draw heavily from the heritage gained from previous rocket missions, while also benefiting from related NASA technology development programs. The Pennsylvania State University (PSU) team has a history of designing and flying spectrometer components onboard rockets while also being scientific leaders in the field of diffuse soft X-ray astronomy. The PSU program will provide hands-on training of young scientists in the techniques of instrumental and observational X-ray astronomy. The proposed rocket program will also expose these researchers to a full experiment cycle: design, fabrication, tolerance analysis, assembly, flight-qualification, calibration, integration, launch, and data analysis; using a combination of technologies suitable for adaptation to NASA's major missions. The PSU program in suborbital X-ray astronomy represents an exciting mix of compelling science, heritage, cutting-edge technology development, and training of future scientists.

Simulation and optimization of the SIRIUS IPE soft x-ray beamline

Science.gov (United States)

Meyer, Bernd C.; Rocha, Tulio C. R.; Luiz, Sergio A. L.; C. Pinto, Artur; Westfahl, Harry

2017-08-01

The soft X-ray beamline IPE is one of the first phase SIRIUS beamlines at the LNLS, Brazil. Divided into two branches, IPE is designed to perform ambient pressure X-ray photo-electron spectroscopy (AP-XPS) and high resolution resonant inelastic X-ray scattering (RIXS) for samples in operando/environmental conditions inside cells and liquid jets. The aim is to maximize the photon flux in the energy range 200-1400 eV generated by an elliptically polarizing undulator source (EPU) and focus it to a 1 μm vertical spot size at the RIXS station and 10 μm at the AP-XPS station. In order to achieve the required resolving power (40.000 at 930 eV) for RIXS both the dispersion properties of the plane grating monochromator (PGM) and the thermal deformation of the optical elements need special attention. The grating parameters were optimized with the REFLEC code to maximize the efficiency at the required resolution. Thermal deformation of the PGM plane mirror limits the possible range of cff parameters depending of the photon energy used. Hence, resolution of the PGM and thermal deformation effects define the boundary conditions of the optical concept and the simulations of the IPE beamline. We compare simulations performed by geometrical ray-tracing (SHADOW) and wave front propagation (SRW) and show that wave front diffraction effects (apertures, optical surface error profiles) has a small effect on the beam spot size and shape.

ISMabs: A COMPREHENSIVE X-RAY ABSORPTION MODEL FOR THE INTERSTELLAR MEDIUM

Energy Technology Data Exchange (ETDEWEB)

Gatuzz, E.; Mendoza, C. [Centro de Física, Instituto Venezolano de Investigaciones Científicas (IVIC), P.O. Box 20632, Caracas 1020A (Venezuela, Bolivarian Republic of); García, J. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, 02138 (United States); Kallman, T. R. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Gorczyca, T. W., E-mail: egatuzz@ivic.gob.ve, E-mail: claudio@ivic.gob.ve, E-mail: javier@head.cfa.harvard.edu, E-mail: timothy.r.kallman@nasa.gov, E-mail: thomas.gorczyca@wmich.edu [Department of Physics, Western Michigan University, Kalamazoo, MI 49008 (United States)

2015-02-10

We present an X-ray absorption model for the interstellar medium, to be referred to as ISMabs, that takes into account both neutral and ionized species of cosmically abundant elements, and includes the most accurate atomic data available. Using high-resolution spectra from eight X-ray binaries obtained with the Chandra High Energy Transmission Grating Spectrometer, we proceed to benchmark the atomic data in the model particularly in the neon K-edge region. Compared with previous photoabsorption models, which solely rely on neutral species, the inclusion of ions leads to improved spectral fits. Fit parameters comprise the column densities of abundant contributors that allow direct estimates of the ionization states. ISMabs is provided in the appropriate format to be implemented in widely used X-ray spectral fitting packages such as XSPEC, ISIS, and SHERPA.

High resolution krypton M/sub 4,5/ x-ray emission spectra

International Nuclear Information System (INIS)

Perera, R.C.C.; Hettrick, M.C.; Lindle, D.W.

1987-10-01

High resolution M/sub 4,5/ (3d → 4p) x-ray emission spectra from a krypton plasma were measured using a recently developed grazing-incidence reflection-grating monochromator/spectrometer with very high flux rates at extreme ultraviolet and soft x-ray wave lengths. The nominal resolving power of the instrument, E/ΔE, is about 300 in this energy range (∼80 eV). Three dipole-allowed 3d → 4p emission lines were observed at 80.98 eV, 80.35 eV and 79.73 eV. A broad peak at about 82.3 eV is tentatively assigned to transitions resulting from Kr 2+ , and effects of excitation energy on M/sub 4,5/ x-ray emission were observed. 9 refs., 3 figs., 1 tab

The Einstein objective grating spectrometer survey of galactic binary X-ray sources

Science.gov (United States)

Vrtilek, S. D.; Mcclintock, J. E.; Seward, F. D.; Kahn, S. M.; Wargelin, B. J.

1991-01-01

The results of observations of 22 bright Galactic X-ray point sources are presented, and the most reliable measurements to date of X-ray column densities to these sources are derived. The results are consistent with the idea that some of the objects have a component of column density intrinsic to the source in addition to an interstellar component. The K-edge absorption due to oxygen is clearly detected in 10 of the sources and the Fe L and Ne K edges are detected in a few. The spectra probably reflect emission originating in a collisionally excited region combined with emission from a photoionized region excited directly by the central source.

Spectral tailoring of nanoscale EUV and soft x-ray multilayer optics

Science.gov (United States)

Huang, Qiushi; Medvedev, Viacheslav; van de Kruijs, Robbert; Yakshin, Andrey; Louis, Eric; Bijkerk, Fred

2017-03-01

Extreme ultraviolet and soft X-ray (XUV) multilayer optics have experienced significant development over the past few years, particularly on controlling the spectral characteristics of light for advanced applications like EUV photolithography, space observation, and accelerator- or lab-based XUV experiments. Both planar and three dimensional multilayer structures have been developed to tailor the spectral response in a wide wavelength range. For the planar multilayer optics, different layered schemes are explored. Stacks of periodic multilayers and capping layers are demonstrated to achieve multi-channel reflection or suppression of the reflective properties. Aperiodic multilayer structures enable broadband reflection both in angles and wavelengths, with the possibility of polarization control. The broad wavelength band multilayer is also used to shape attosecond pulses for the study of ultrafast phenomena. Narrowband multilayer monochromators are delivered to bridge the resolution gap between crystals and regular multilayers. High spectral purity multilayers with innovated anti-reflection structures are shown to select spectrally clean XUV radiation from broadband X-ray sources, especially the plasma sources for EUV lithography. Significant progress is also made in the three dimensional multilayer optics, i.e., combining micro- and nanostructures with multilayers, in order to provide new freedom to tune the spectral response. Several kinds of multilayer gratings, including multilayer coated gratings, sliced multilayer gratings, and lamellar multilayer gratings are being pursued for high resolution and high efficiency XUV spectrometers/monochromators, with their advantages and disadvantages, respectively. Multilayer diffraction optics are also developed for spectral purity enhancement. New structures like gratings, zone plates, and pyramids that obtain full suppression of the unwanted radiation and high XUV reflectance are reviewed. Based on the present achievement

Linear information retrieval method in X-ray grating-based phase contrast imaging and its interchangeability with tomographic reconstruction

Science.gov (United States)

Wu, Z.; Gao, K.; Wang, Z. L.; Shao, Q. G.; Hu, R. F.; Wei, C. X.; Zan, G. B.; Wali, F.; Luo, R. H.; Zhu, P. P.; Tian, Y. C.

2017-06-01

In X-ray grating-based phase contrast imaging, information retrieval is necessary for quantitative research, especially for phase tomography. However, numerous and repetitive processes have to be performed for tomographic reconstruction. In this paper, we report a novel information retrieval method, which enables retrieving phase and absorption information by means of a linear combination of two mutually conjugate images. Thanks to the distributive law of the multiplication as well as the commutative law and associative law of the addition, the information retrieval can be performed after tomographic reconstruction, thus simplifying the information retrieval procedure dramatically. The theoretical model of this method is established in both parallel beam geometry for Talbot interferometer and fan beam geometry for Talbot-Lau interferometer. Numerical experiments are also performed to confirm the feasibility and validity of the proposed method. In addition, we discuss its possibility in cone beam geometry and its advantages compared with other methods. Moreover, this method can also be employed in other differential phase contrast imaging methods, such as diffraction enhanced imaging, non-interferometric imaging, and edge illumination.

Comparison of contrast-to-noise ratios of transmission and dark-field signal in grating-based X-ray imaging for healthy murine lung tissue

International Nuclear Information System (INIS)

Schwab, Felix; Schleede, Simone; Hahn, Dieter

2013-01-01

Purpose: An experimental comparison of the contrast-to-noise ratio (CNR) between transmission and dark-field signals in grating-based X-ray imaging for ex-vivo murine lung tissue. Materials and Methods: Lungs from three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Background noise of transmission and dark-field signal was quantified by measuring the standard deviation in a region of interest (ROI) placed in a homogeneous area outside the specimen. Image contrast was quantified by measuring the signal range in rectangular ROIs placed in central and peripheral lung parenchyma. The relative contrast gain (RCG) of dark-field over transmission images was calculated as CNRDF / CNRT. Results: In all images, there was a trend for contrast-to-noise ratios of dark-field images (CNRDF) to be higher than for transmission images (CNRT) for all ROIs (median 61 vs. 38, p = 0.10), but the difference was statistically significant only for peripheral ROIs (61 vs. 32, p = 0.03). Median RCG was >1 for all ROIs (1.84). RCG values were significantly smaller for central ROIs than for peripheral ROIs (1.34 vs. 2.43, p = 0.03). Conclusion: The contrast-to-noise ratio of dark-field images compares more favorably to the contrast-to-noise ratio of transmission images for peripheral lung regions as compared to central regions. For any specific specimen, a calculation of the RCG allows comparing which X-ray modality (dark-field or transmission imaging) produces better contrast-to-noise characteristics in a well-defined ROI. (orig.)

Design of compressors for FEL pulses using deformable gratings

Science.gov (United States)

Bonora, Stefano; Fabris, Nicola; Frassetto, Fabio; Giovine, Ennio; Miotti, Paolo; Quintavalla, Martino; Poletto, Luca

2017-06-01

We present the optical layout of soft X-rays compressors using reflective grating specifically designed to give both positive or negative group-delay dispersion (GDD). They are tailored for chirped-pulse-amplification experiments with FEL sources. The optical design originates from an existing compressor with plane gratings already realized and tested at FERMI, that has been demonstrated capable to introduce tunable negative GDD. Here, we discuss two novel designs for compressors using deformable gratings capable to give both negative and positive GDD. Two novel designs are discussed: 1) a design with two deformable gratings and an intermediate focus between the twos, that is demonstrated capable to introduce positive GDD; 2) a design with one deformable grating giving an intermediate focus, followed by a concave mirror and a plane grating, that is capable to give both positive and negative GDD depending on the distance between the second mirror and the second grating. Both the designs are tunable in wavelength and GDD, by acting on the deformable gratings, that are rotated to tune the wavelength and the GDD and deformed to introduce the radius required to keep the spectral focus. The deformable gratings have a laminar profile and are ruled on a thin silicon plane substrate. A piezoelectric actuator is glued on the back of the substrate and is actuated to give a radius of curvature that is varying from infinite (plane) to few meters. The ruling procedure, the piezoelectric actuator and the efficiency measurements in the soft X-rays will be presented. Some test cases are discussed for wavelengths shorter than 12 nm.

Recent X-ray hybrid CMOS detector developments and measurements

Science.gov (United States)

Hull, Samuel V.; Falcone, Abraham D.; Burrows, David N.; Wages, Mitchell; Chattopadhyay, Tanmoy; McQuaide, Maria; Bray, Evan; Kern, Matthew

2017-08-01

The Penn State X-ray detector lab, in collaboration with Teledyne Imaging Sensors (TIS), have progressed their efforts to improve soft X-ray Hybrid CMOS detector (HCD) technology on multiple fronts. Having newly acquired a Teledyne cryogenic SIDECARTM ASIC for use with HxRG devices, measurements were performed with an H2RG HCD and the cooled SIDECARTM. We report new energy resolution and read noise measurements, which show a significant improvement over room temperature SIDECARTM operation. Further, in order to meet the demands of future high-throughput and high spatial resolution X-ray observatories, detectors with fast readout and small pixel sizes are being developed. We report on characteristics of new X-ray HCDs with 12.5 micron pitch that include in-pixel CDS circuitry and crosstalk-eliminating CTIA amplifiers. In addition, PSU and TIS are developing a new large-scale array Speedster-EXD device. The original 64 × 64 pixel Speedster-EXD prototype used comparators in each pixel to enable event driven readout with order of magnitude higher effective readout rates, which will now be implemented in a 550 × 550 pixel device. Finally, the detector lab is involved in a sounding rocket mission that is slated to fly in 2018 with an off-plane reflection grating array and an H2RG X-ray HCD. We report on the planned detector configuration for this mission, which will increase the NASA technology readiness level of X-ray HCDs to TRL 9.

Quantitative measurements with x-ray microscopes in laser-fusion experiments

International Nuclear Information System (INIS)

Marshall, F.J.; Su, Q.

1995-01-01

X-ray imaging of laser-fusion target implosions has been performed on the University of Rochester's OMEGA laser system by means of grazing-incidence optical imaging with Kirkpatrick--Baez (KB) microscopes. High spatial resolution imaging (∼5 μm) of hard x-ray emission (up to ∼7 keV) has been achieved. New grazing-incidence optics are currently being fabricated for the OMEGA Upgrade experimental laser-fusion facility. Projected performance indicates that resolution may be increased to ∼2 μm at the center of the field of view and sensitivity extended to ∼8 keV. Uses of KB microscopes on the OMEGA Upgrade will include hard x-ray imaging, grating-dispersed imaged spectroscopy, and framed imaging. A novel technique for monochromatic imaging with KB microscopes has also been demonstrated enabling images of target emission in a narrow energy band (10 to 20 eV) to be obtained

Investigating the interaction of x-ray free electron laser radiation with grating structure

NARCIS (Netherlands)

Gaudin, J.; Ozkan, C.; Chalupsky, J.; Bajt, S.; Burian, T.; Vysin, L.; Coppola, N.; Farahani, S. D.; Chapman, H. N.; Galasso, G.; Hajkova, V.; Harmand, M.; Juha, L.; Jurek, M.; Loch, R. A.; Möller, S.; Nagasono, M.; Stormer, M.; Sinn, H.; Saksl, K.; Sobierajski, R.; Schulz, J.; Sovak, P.; Toleikis, S.; Tiedtke, K.; Tschentscher, T.; Krzywinski, J.

2012-01-01

The interaction of free electron laser pulses with grating structure is investigated using 4.6 +/- 0.1 nm radiation at the FLASH facility in Hamburg. For fluences above 63.7 +/- 8.7 mJ/cm(2), the interaction triggers a damage process starting at the edge of the grating structure as evidenced by

High-speed X-ray phase tomography with Talbot interferometer and fringe scanning method

International Nuclear Information System (INIS)

Kibayashi, Shunsuke; Harasse, Sébastien; Yashiro, Wataru; Momose, Atsushi

2012-01-01

High-speed X-ray phase tomography based on the Fourier-transform method has been demonstrated with an X-ray Talbot interferometer using white synchrotron radiation. We report the experimental results of high-speed X-ray phase tomography with fringe-scanning method instead of Fourier-transform method to improve spatial resolution without a considerable increase of scan time. To apply fringe-scanning method to high speed tomography, we tested a scan that is a synchronous combination of one-way continuous movements of the sample rotation and the grating displacement. When this scanning method was combined with X-ray phase tomography, we were able to obtain a scan time of 5 s. A comparison of the image quality derived with the conventional approach and with the proposed approach using the fringe-scanning method showed that the latter had better spatial resolution.

CHANDRA AND XMM-NEWTON X-RAY OBSERVATIONS OF THE HYPERACTIVE T TAURI STAR RY TAU

Energy Technology Data Exchange (ETDEWEB)

Skinner, Stephen L. [Center for Astrophysics and Space Astronomy (CASA), Univ. of Colorado, Boulder, CO 80309-0389 (United States); Audard, Marc [Dept. of Astronomy, University of Geneva, Ch. d’Ecogia 16, CH-1290 Versoix (Switzerland); Güdel, Manuel, E-mail: stephen.skinner@colorado.edu, E-mail: marc.audard@unige.ch, E-mail: manuel.guedel@univie.ac.at [Dept. of Astrophysics, Univ. of Vienna, Türkenschanzstr. 17, A-1180 Vienna (Austria)

2016-07-20

We present results of pointed X-ray observations of the accreting jet-driving T Tauri star RY Tau using Chandra and XMM-Newton . We obtained high-resolution grating spectra and excellent-quality CCD spectra and light curves with the objective of identifying the physical mechanisms underlying RY Tau’s bright X-ray emission. Grating spectra reveal numerous emission lines spanning a broad range of temperature superimposed on a hot continuum. The X-ray emission measure distribution is dominated by very hot plasma at T {sub hot} ∼ 50 MK, but higher temperatures were present during flares. A weaker cool plasma component is also present as revealed by low-temperature lines such as O viii. X-ray light curves show complex variability consisting of short-duration (∼hours) superhot flares accompanied by fluorescent Fe emission at 6.4 keV superimposed on a slowly varying (∼one day) component that may be tied to stellar rotation. The hot flaring component is undoubtedly of magnetic (e.g., coronal) origin. Soft- and hard-band light curves undergo similar slow variability implying that at least some of the cool plasma shares a common magnetic origin with the hot plasma. Any contribution to the X-ray emission from cool shocked plasma is small compared to the dominant hot component but production of individual low-temperature lines such as O viii in an accretion shock is not ruled out.

A Technology Development Roadmap for a Near-Term Probe-Class X-ray Astrophysics Mission

Science.gov (United States)

Daelemans, Gerard J.; Petre, Robert; Bookbinder, Jay; Ptak, Andrew; Smith, Randall

2013-01-01

This document presents a roadmap, including proposed budget and schedule, for maturing the instrumentation needed for an X-ray astrophysics Probe-class mission. The Physics of the Cosmos (PCOS) Program Office was directed to create this roadmap following the December 2012 NASA Astrophysics Implementation Plan (AIP). Definition of this mission is called for in the AIP, with the possibility of selection in 2015 for a start in 2017. The overall mission capabilities and instrument performance requirements were defined in the 2010 Astronomy and Astrophysics Decadal Survey report, New Worlds, New Horizons in Astronomy and Astrophysics (NWNH), in connection with the highly ranked International X-ray Observatory (IXO). In NWNH, recommendations were provided regarding the size of, and instrumentation needed by, the next large X-ray observatory. Specifically, the key instrumental capability would be an X-ray calorimeter spectrometer at the focus of a large mirror with angular resolution of 10 arc seconds (arcsec) or better. If possible, a grating spectrometer should also be incorporated into the instrument complement. In response to these recommendations, four instrumentation technologies are included in this roadmap. Three of these are critical for an X-ray mission designed to address NWNH questions: segmented X-ray mirrors, transition edge sensor calorimeters, and gratings. Two approaches are described for gratings, which represent the least mature technology and thus most in need of a parallel path for risk reduction. Also, while current CCD detectors would likely meet the mission needs for grating spectrum readout, specific improvements are included as an additional approach for achieving the grating system effective area requirement. The technical steps needed for these technologies to attain technology readiness levels (TRL) of 5 and 6 are described, as well as desirable modest risk reduction steps beyond TRL-6. All of the technology development efforts are currently

Absolute Soft X-ray Emission Measurements at the Nike Laser

Science.gov (United States)

Weaver, J.; Atkin, R.; Boyer, C.; Colombant, D.; Feldman, U.; Fielding, D.; Gardner, J.; Holland, G.; Klapisch, M.; Mostovych, A. N.; Obenscain, S.; Seely, J. F.

2002-11-01

Recent experiments at the Nike laser facility have demonstrated that, when a low intensity prepulse ( 2main laser intensity) is used to heat a thin Au or Pd coating on a planar CH target, the growth of non-uniformities due to laser imprint can be reduced from the growth observed for an uncoated CH target. The absolute radiation intensity in the soft x-ray region (0.1-1 keV) has a important role in the energy balance for layered targets. There is an ongoing effort to characterize the soft x-ray emission using an absolutely calibrated transmission grating spectrometer and filtered diode modules. Measurements of the angular distribution of the emission from unlayered solid targets (Au, Pd, CH) have recently been made using an array of moveable filtered diode modules. The data from the angular distribution studies will be presented. A new absolutely calibrated, time-resolving transmission grating spectrometer has been installed at the Nike. The new version has improved spectral resolution, selectable transmission filters, and the potential for simultaneous temporal, spatial, and spectral resolution. Preliminary data from the new spectrometer will be presented and future experiments will be briefly discussed. *Work was supported by DoE

Quadratic grating apodized photon sieves for simultaneous multiplane microscopy

Science.gov (United States)

Cheng, Yiguang; Zhu, Jiangping; He, Yu; Tang, Yan; Hu, Song; Zhao, Lixin

2017-10-01

We present a new type of imaging device, named quadratic grating apodized photon sieve (QGPS), used as the objective for simultaneous multiplane imaging in X-rays. The proposed QGPS is structured based on the combination of two concepts: photon sieves and quadratic gratings. Its design principles are also expounded in detail. Analysis of imaging properties of QGPS in terms of point-spread function shows that QGPS can image multiple layers within an object field onto a single image plane. Simulated and experimental results in visible light both demonstrate the feasibility of QGPS for simultaneous multiplane imaging, which is extremely promising to detect dynamic specimens by X-ray microscopy in the physical and life sciences.

Time-resolved soft x-ray spectra from laser-produced Cu plasma

International Nuclear Information System (INIS)

Cone, K.V.; Dunn, J.; Baldis, H.A.; May, M.J.; Purvis, M.A.; Scott, H.A.; Schneider, M.B.

2012-01-01

The volumetric heating of a thin copper target has been studied with time resolved x-ray spectroscopy. The copper target was heated from a plasma produced using the Lawrence Livermore National Laboratory's Compact Multipulse Terrawatt (COMET) laser. A variable spaced grating spectrometer coupled to an x-ray streak camera measured soft x-ray emission (800-1550 eV) from the back of the copper target to characterize the bulk heating of the target. Radiation hydrodynamic simulations were modeled in 2-dimensions using the HYDRA code. The target conditions calculated by HYDRA were post-processed with the atomic kinetics code CRETIN to generate synthetic emission spectra. A comparison between the experimental and simulated spectra indicates the presence of specific ionization states of copper and the corresponding electron temperatures and ion densities throughout the laser-heated copper target.

At-wavelength metrology of x-ray optics at Diamond Light Source

Science.gov (United States)

Wang, Hongchang; Berujon, Sebastien; Sutter, John; Alcock, Simon G.; Sawhney, Kawal

2014-09-01

Modern, third-generation synchrotron radiation sources provide coherent and extremely bright beams of X-ray radiation. The successful exploitation of such beams depends to a significant extent on imperfections and misalignment of the optics employed on the beamlines. This issue becomes even more critical with the increasing use of active optics, and the desire to achieve diffraction-limited and coherence-preserving X-ray beams. In recent years, significant progress has been made to improve optic testing and optimization techniques, especially those using X-rays for so-called atwavelength metrology. These in-situ and at-wavelength metrology methods can be used not only to optimize the performance of X-ray optics, but also to correct and minimize the collective distortions of upstream beamline optics, including monochromators, and transmission windows. An overview of at-wavelength metrology techniques implemented at Diamond Light Source is presented, including grating interferometry and X-ray near-field speckle based techniques. Representative examples of the application of these techniques are also given, including in-situ and atwavelength calibration and optimization of: active, piezo bimorph mirrors; Kirkpatrick-Baez (KB) mirrors; and refractive optics such as compound refractive lenses.

Grating-based tomography applications in biomedical engineering

Science.gov (United States)

Schulz, Georg; Thalmann, Peter; Khimchenko, Anna; Müller, Bert

2017-10-01

For the investigation of soft tissues or tissues consisting of soft and hard tissues on the microscopic level, hard X-ray phase tomography has become one of the most suitable imaging techniques. Besides other phase contrast methods grating interferometry has the advantage of higher sensitivity than inline methods and the quantitative results. One disadvantage of the conventional double-grating setup (XDGI) compared to inline methods is the limitation of the spatial resolution. This limitation can be overcome by removing the analyser grating resulting in a single-grating setup (XSGI). In order to verify the performance of XSGI concerning contrast and spatial resolution, a quantitative comparison of XSGI and XDGI tomograms of a human nerve was performed. Both techniques provide sufficient contrast to allow for the distinction of tissue types. The spatial resolution of the two-fold binned XSGI data set is improved by a factor of two in comparison to XDGI which underlies its performance in tomography of soft tissues. Another application for grating-based X-ray phase tomography is the simultaneous visualization of soft and hard tissues of a plaque-containing coronary artery. The simultaneous visualization of both tissues is important for the segmentation of the lumen. The segmented data can be used for flow simulations in order to obtain information about the three-dimensional wall shear stress distribution needed for the optimization of mechano-sensitive nanocontainers used for drug delivery.

SOFT X-RAY IRRADIATION OF SILICATES: IMPLICATIONS FOR DUST EVOLUTION IN PROTOPLANETARY DISKS

Energy Technology Data Exchange (ETDEWEB)

Ciaravella, A.; Cecchi-Pestellini, C.; Jiménez-Escobar, A. [INAF—Osservatorio Astronomico di Palermo, P.za Parlamento 1, I-90134 Palermo (Italy); Chen, Y.-J.; Huang, C.-H. [Department of Physics, National Central University, Jhongli City, Taoyuan County 32054, Taiwan (China); Muñoz Caro, G. M. [Centro de Astrobiología (INTA-CSIC), Carretera de Ajalvir, km 4, Torrejón de Ardoz, E-28850 Madrid (Spain); Venezia, A. M., E-mail: aciaravella@astropa.unipa.it [ISMN—CNR, Via Ugo La Malfa 153, I-90146 Palermo (Italy)

2016-09-01

The processing of energetic photons on bare silicate grains was simulated experimentally on silicate films submitted to soft X-rays of energies up to 1.25 keV. The silicate material was prepared by means of a microwave assisted sol–gel technique. Its chemical composition reflects the Mg{sub 2}SiO{sub 4} stoichiometry with residual impurities due to the synthesis method. The experiments were performed using the spherical grating monochromator beamline at the National Synchrotron Radiation Research Center in Taiwan. We found that soft X-ray irradiation induces structural changes that can be interpreted as an amorphization of the processed silicate material. The present results may have relevant implications in the evolution of silicate materials in X-ray-irradiated protoplanetary disks.

X-ray phase-contrast CT of a pancreatic ductal adenocarcinoma mouse model.

Directory of Open Access Journals (Sweden)

Arne Tapfer

Full Text Available To explore the potential of grating-based x-ray phase-contrast computed tomography (CT for preclinical research, a genetically engineered mouse model of pancreatic ductal adenocarcinoma (PDAC was investigated. One ex-vivo mouse specimen was scanned with different grating-based phase-contrast CT imaging setups covering two different settings: i high-resolution synchrotron radiation (SR imaging and ii dose-reduced imaging using either synchrotron radiation or a conventional x-ray tube source. These experimental settings were chosen to assess the potential of phase-contrast imaging for two different types of application: i high-performance imaging for virtual microscopy applications and ii biomedical imaging with increased soft-tissue contrast for in-vivo applications. For validation and as a reference, histological slicing and magnetic resonance imaging (MRI were performed on the same mouse specimen. For each x-ray imaging setup, attenuation and phase-contrast images were compared visually with regard to contrast in general, and specifically concerning the recognizability of lesions and cancerous tissue. To quantitatively assess contrast, the contrast-to-noise ratios (CNR of selected regions of interest (ROI in the attenuation images and the phase images were analyzed and compared. It was found that both for virtual microscopy and for in-vivo applications, there is great potential for phase-contrast imaging: in the SR-based benchmarking data, fine details about tissue composition are accessible in the phase images and the visibility of solid tumor tissue under dose-reduced conditions is markedly superior in the phase images. The present study hence demonstrates improved diagnostic value with phase-contrast CT in a mouse model of a complex endogenous cancer, promoting the use and further development of grating-based phase-contrast CT for biomedical imaging applications.

Design of MiSolFA Hard X-Ray Imager

Science.gov (United States)

Lastufka, Erica; Casadei, Diego

2017-08-01

Advances in the study of coronal electron-accelerating regions have so far been limited by the dynamic range of X-ray instruments. A quick and economical alternative to desirable focusing optics technology is stereo observation. The micro-satellite MiSolFA (Micro Solar-Flare Apparatus) is designed both as a stand-alone X-ray imaging spectrometer and a complement to the Spectrometer/Telescope for Imaging X-rays (STIX) mission. These instruments will be the first pair of cross-calibrated X-ray imaging spectrometers to look at solar flares from very different points of view. MiSolFA will achieve indirect imaging between 10 and 60 keV and provide spectroscopy up to 100 keV, equipped with grids producing moiré patterns in a similar way to STIX. New manufacturing techniques produce gold gratings on a graphite or silicon substrate, with periods ranging from 15 to 225 micrometers, separated by a distance of 15.47 cm, to achieve a spatial resolutions from 10" to 60" (as compared to RHESSI's separation of 150 cm and 1" resolution). We present the progress of the imager design, the performance of the first prototypes, and reach out to the community for further scientific objectives to consider in optimizing the final design.

Analysis of the 3C 445 soft X-ray spectrum as observed by Chandra high-energy gratings

Science.gov (United States)

Dong, Fu-Tong; Shao, Shu-Hua; Cheng, Yan; Zeng, Jiao-Long

2018-05-01

We present a detailed analysis of the soft X-ray emission of 3C 445 using an archival Chandra High Energy Transmission Grating (HETG) spectrum. Highly-ionized H- and He-like Mg, Si and S lines, as well as a resolved low-ionized Si Kα line, are detected in the high resolution spectrum. The He-like triplets of Mg and Si are resolved into individual lines, and the calculated R ratios indicate a high density for the emitter. The low values of G ratios indicate the lines originate from collisionally ionized plasmas. However, the detection of a resolved narrow Ne X radiative recombination continua (RRC) feature in the spectrum seems to prefer a photoionized environment. The spectrum is subsequently modeled with a photoionization model, and the results are compared with those of a collisional model. Through a detailed analysis of the spectrum, we exclude a collisional origin for these emission lines. A one-component photoionization model provides a great fit to the emission features. The best-fit parameters are {log} ξ ={3.3}-0.3+0.4 erg cm s‑1, {n}{{H}}={5}-4.5+15× {10}10 cm‑3 and {N}{{H}}={2.5}-1.7+3.8× {10}20 cm‑2. According to the calculated high density for the emitter, the measured velocity widths of the emission lines and the inferred radial distance (6 × 1014 – 8 × 1015 cm), we suggest the emission lines originating from matter are located in the broad line region (BLR).

X-ray filter for x-ray powder diffraction

Science.gov (United States)

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.

X-ray phase-contrast computed tomography visualizes the microstructure and degradation profile of implanted biodegradable scaffolds after spinal cord injury

Energy Technology Data Exchange (ETDEWEB)

Takashima, Kenta, E-mail: takashima-k@med.tohoku.ac.jp [Tohoku University Graduate School of Medicine, Sendai (Japan); University of Tokyo, Tokyo (Japan); Hoshino, Masato; Uesugi, Kentaro; Yagi, Naoto [SPring-8, Hyogo (Japan); Matsuda, Shojiro [Gunze Limited, Shiga (Japan); Nakahira, Atsushi [Osaka Prefecture University, Osaka (Japan); Osumi, Noriko; Kohzuki, Masahiro [Tohoku University Graduate School of Medicine, Sendai (Japan); Onodera, Hiroshi [University of Tokyo, Tokyo (Japan)

2015-01-01

X-ray phase-contrast computed tomography imaging based on the Talbot grating interferometer is described, and the way it can visualize the polyglycolic acid scaffold, including its microfibres, after implantation into the injured spinal cord is shown. Tissue engineering strategies for spinal cord repair are a primary focus of translational medicine after spinal cord injury (SCI). Many tissue engineering strategies employ three-dimensional scaffolds, which are made of biodegradable materials and have microstructure incorporated with viable cells and bioactive molecules to promote new tissue generation and functional recovery after SCI. It is therefore important to develop an imaging system that visualizes both the microstructure of three-dimensional scaffolds and their degradation process after SCI. Here, X-ray phase-contrast computed tomography imaging based on the Talbot grating interferometer is described and it is shown how it can visualize the polyglycolic acid scaffold, including its microfibres, after implantation into the injured spinal cord. Furthermore, X-ray phase-contrast computed tomography images revealed that degradation occurred from the end to the centre of the braided scaffold in the 28 days after implantation into the injured spinal cord. The present report provides the first demonstration of an imaging technique that visualizes both the microstructure and degradation of biodegradable scaffolds in SCI research. X-ray phase-contrast imaging based on the Talbot grating interferometer is a versatile technique that can be used for a broad range of preclinical applications in tissue engineering strategies.

X-ray fluorescence imaging with polycapillary X-ray optics

International Nuclear Information System (INIS)

Yonehara, Tasuku; Yamaguchi, Makoto; Tsuji, Kouichi

2010-01-01

X-ray fluorescence spectrometry imaging is a powerful tool to provide information about the chemical composition and elemental distribution of a specimen. X-ray fluorescence spectrometry images were conventionally obtained by using a μ-X-ray fluorescence spectrometry spectrometer, which requires scanning a sample. Faster X-ray fluorescence spectrometry imaging would be achieved by eliminating the process of sample scanning. Thus, we developed an X-ray fluorescence spectrometry imaging instrument without sample scanning by using polycapillary X-ray optics, which had energy filter characteristics caused by the energy dependence of the total reflection phenomenon. In the present paper, we show that two independent straight polycapillary X-ray optics could be used as an energy filter of X-rays for X-ray fluorescence. Only low energy X-rays were detected when the angle between the two optical axes was increased slightly. Energy-selective X-ray fluorescence spectrometry images with projection mode were taken by using an X-ray CCD camera equipped with two polycapillary optics. It was shown that Fe Kα (6.40 keV) and Cu Kα (8.04 keV) could be discriminated for Fe and Cu foils.

Polarized high-brilliance and high-resolution soft x-ray source at ELETTRA: The performance of beamline BACH

International Nuclear Information System (INIS)

Zangrando, M.; Zacchigna, M.; Finazzi, M.; Cocco, D.; Rochow, R.; Parmigiani, F.

2004-01-01

BACH, a soft x-ray beamline for polarization-dependent experiments at the Italian synchrotron radiation facility ELETTRA, was recently completed and characterized. Its performance, in terms of energy resolution, flux and polarization, is presented. Based on two APPLE II undulators, BACH covers the energy range between 35 and 1600 eV with the control of the light polarization. The monochromator is equipped with four gratings and allows one to work either in a high resolution or in a high flux mode. After the monochromator, the beamline is split into two branches with different refocusing properties. One is optimized to exploit the performance of the soft x-ray spectrometer (ComIXS) available at the beamline. Resolving powers between 12000 at 90 eV photon energy and 6600 near 867 eV were achieved using the high-resolution gratings and the smallest available slit width (10 μm). For the high-brilliance grating, which works between 290 and 1600 eV, resolving powers between 7000 at 400 eV and 2200 at 867 eV were obtained. The flux in the experimental chamber, measured with the high-resolution gratings for linearly polarized light at the best achievable resolution, ranges between 4x10 11 photons/s at 125 eV and 2x10 10 photons/s between 900 and 1250 eV. In circularly polarized mode the flux is two times larger for energies up to 380 eV. A gain of nearly one order of magnitude is obtained for the high-brilliance grating, in accordance with theoretical predictions. Flux beyond 1.3x10 11 photons/s was measured up to 1300 eV, and thus over nearly the complete energy range covered by this high-brilliance grating, with a maximum of 1.6x10 11 photons/s between 800 and 1100 eV. First results from polarization measurements confirm a polarization above 99.7% for both linearly and circularly polarized modes at low energies. Circular dichroism experiments indicate a circular polarization beyond 90% at the Fe L 2 /L 3 edge near 720 eV

A DEEP X-RAY VIEW OF THE BARE AGN ARK 120. I. REVEALING THE SOFT X-RAY LINE EMISSION

Energy Technology Data Exchange (ETDEWEB)

Reeves, J. N.; Braito, V. [Center for Space Science and Technology, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States); Porquet, D. [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Nardini, E. [Astrophysics Group, School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire, ST5 5BG (United Kingdom); Lobban, A. [Dept of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Turner, T. J., E-mail: jreeves@umbc.edu, E-mail: j.n.reeves@keele.ac.uk [Department of Physics, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States)

2016-09-10

The Seyfert 1 galaxy Ark 120 is a prototype example of the so-called class of bare nucleus active galactic nuclei (AGNs), whereby there is no known evidence for the presence of ionized gas along the direct line of sight. Here deep (>400 ks exposure), high-resolution X-ray spectroscopy of Ark 120 is presented from XMM-Newton observations that were carried out in 2014 March, together with simultaneous Chandra /High Energy Transmission Grating exposures. The high-resolution spectra confirmed the lack of intrinsic absorbing gas associated with Ark 120, with the only X-ray absorption present originating from the interstellar medium (ISM) of our own Galaxy, with a possible slight enhancement of the oxygen abundance required with respect to the expected ISM values in the solar neighborhood. However, the presence of several soft X-ray emission lines are revealed for the first time in the XMM-Newton RGS spectrum, associated with the AGN and arising from the He- and H-like ions of N, O, Ne, and Mg. The He-like line profiles of N, O, and Ne appear velocity broadened, with typical FWHMs of ∼5000 km s{sup −1}, whereas the H-like profiles are unresolved. From the clean measurement of the He-like triplets, we deduce that the broad lines arise from a gas of density n {sub e} ∼ 10{sup 11} cm{sup −3}, while the photoionization calculations infer that the emitting gas covers at least 10% of 4 π steradian. Thus the broad soft X-ray profiles appear coincident with an X-ray component of the optical–UV broad-line region on sub-parsec scales, whereas the narrow profiles originate on larger parsec scales, perhaps coincident with the AGN narrow-line region. The observations show that Ark 120 is not intrinsically bare and substantial X-ray-emitting gas exists out of our direct line of sight toward this AGN.

X-Ray Absorption with Transmission X-Ray Microscopes

NARCIS (Netherlands)

de Groot, F.M.F.

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

X-ray Binaries in the Central Region of M31

Science.gov (United States)

Trudolyubov, Sergey P.; Priedhorsky, W. C.; Cordova, F. A.

2006-09-01

We present the results of the systematic survey of X-ray sources in the central region of M31 using the data of XMM-Newton observations. The spectral properties and variability of 124 bright X-ray sources were studied in detail. We found that more than 80% of sources observed in two or more observations show significant variability on the time scales of days to years. At least 50% of the sources in our sample are spectrally variable. The fraction of variable sources in our survey is much higher than previously reported from Chandra survey of M31, and is remarkably close to the fraction of variable sources found in M31 globular cluster X-ray source population. We present spectral distribution of M31 X-ray sources, based on the spectral fitting with a power law model. The distribution of spectral photon index has two main peaks at 1.8 and 2.3, and shows clear evolution with source luminosity. Based on the similarity of the properties of M31 X-ray sources and their Galactic counterparts, we expect most of X-ray sources in our sample to be accreting binary systems with neutron star and black hole primaries. Combining the results of X-ray analysis (X-ray spectra, hardness-luminosity diagrams and variability) with available data at other wavelengths, we explore the possibility of distinguishing between bright neutron star and black hole binary systems, and identify 7% and 25% of sources in our sample as a probable black hole and neutron star candidates. Finally, we compare the M31 X-ray source population to the source populations of normal galaxies of different morphological type. Support for this work was provided through NASA Grant NAG5-12390. Part of this work was done during a summer workshop ``Revealing Black Holes'' at the Aspen Center for Physics, S. T. is grateful to the Center for their hospitality.

Mechanical design aspects of a soft X-ray plane grating monochromator

Czech Academy of Sciences Publication Activity Database

Vašina, R.; Kolařík, V.; Doležel, P.; Mynář, M.; Vondráček, Martin; Cháb, Vladimír; Slezák, Jiří; Comicioli, C.; Prince, K. C.

467-468, 467-468 (2001), s. 561-564 ISSN 0168-9002 R&D Projects: GA ČR GV202/98/K002 Grant - others:-(XE) CIPA-CT94-0217 Institutional research plan: CEZ:AV0Z2041904 Keywords : synchrotron radiation * monochromator * plane grating Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.026, year: 2001

Image fusion in x-ray differential phase-contrast imaging

Science.gov (United States)

Haas, W.; Polyanskaya, M.; Bayer, F.; Gödel, K.; Hofmann, H.; Rieger, J.; Ritter, A.; Weber, T.; Wucherer, L.; Durst, J.; Michel, T.; Anton, G.; Hornegger, J.

2012-02-01

Phase-contrast imaging is a novel modality in the field of medical X-ray imaging. The pioneer method is the grating-based interferometry which has no special requirements to the X-ray source and object size. Furthermore, it provides three different types of information of an investigated object simultaneously - absorption, differential phase-contrast and dark-field images. Differential phase-contrast and dark-field images represent a completely new information which has not yet been investigated and studied in context of medical imaging. In order to introduce phase-contrast imaging as a new modality into medical environment the resulting information about the object has to be correctly interpreted. The three output images reflect different properties of the same object the main challenge is to combine and visualize these data in such a way that it diminish the information explosion and reduce the complexity of its interpretation. This paper presents an intuitive image fusion approach which allows to operate with grating-based phase-contrast images. It combines information of the three different images and provides a single image. The approach is implemented in a fusion framework which is aimed to support physicians in study and analysis. The framework provides the user with an intuitive graphical user interface allowing to control the fusion process. The example given in this work shows the functionality of the proposed method and the great potential of phase-contrast imaging in medical practice.

X-ray astronomy

International Nuclear Information System (INIS)

Giacconi, R.; Gursky, H.

1974-01-01

This text contains ten chapters and three appendices. Following an introduction, chapters two through five deal with observational techniques, mechanisms for the production of x rays in a cosmic setting, the x-ray sky and solar x-ray emission. Chapters six through ten include compact x-ray sources, supernova remnants, the interstellar medium, extragalactic x-ray sources and the cosmic x-ray background. Interactions of x rays with matter, units and conversion factors and a catalog of x-ray sources comprise the three appendices. (U.S.)

X-ray optics, a vital aspect of work with synchrotron radiation

International Nuclear Information System (INIS)

Bilderback, D.H.

1986-01-01

The kind of optical components that have been developed over the centuries to make use of visible light won't work for x-rays. New ways must be found to manipulate the much shorter-wavelength x-ray beams to produce effects similar to those achieved with such familiar devices as mirrors, lenses, prisms, and gratings. This is the province of the field of x-ray optics. One challenge is to design optical elements that can focus, disperse, or reflect beams in the x-ray region of the electromagnetic spectrum, where wavelengths are about a thousand times shorter than those in the region of visible light. A second problem is encountered in using the intense, high-energy x-radiation from a synchrotron: how to make the desired beam accessible to a user who is conducting an experiment in a shielded enclosure many meters away from the synchrotron storage ring. Depending on the application, one might want to pick out a single wavelength from the broad spectrum available from the synchrotron, or isolate a narrow band of wavelengths. Then the beam must be collimated. When samples to be exposed are of millimeter dimension or smaller, it may be desirable to increase the intensity by focusing the x-ray beam horizontally and vertically. All these manipulations are analogous to those done with visible light, but the shape and form of the optical components can be quite different

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

Atomic Physics Measurements in Support of X-ray Astronomy

Science.gov (United States)

Beiersdorfer, Peter; Brown, G. V.; Kelley, R. E.; Kilbourne, C. A.; Leutenegger, M.; Porter, F. S.; Obst, M.; Lepson, J. K.; Desai, P.; Gu, M. F.

2010-10-01

X-ray astronomy has been a voracious consumer of atomic data, especially after the launch of the Chandra and XMM-Newton X-ray Observatories, which have produced very high-resolution grating spectra of point sources. One of the important issues has been to understand the physics underlying the Fe L-shell spectra, and the Fe XVII spectrum in particular. A lot of progress has been made, including measurements of the electron-impact and resonance excitation cross sections, which now provides a rather clear picture of the production mechanism of the Fe XVII spectrum. Recent measurements of the radiative rates provide additional information on the deexcitation channels, while investigations of dielectronic satellite transitions provide a measure of the electron temperature. Many questions, however, still remain. Work at LLNL was performed under the auspices of DOE under contract DE-AC53-07NA27344 and supported by NASA's APRA program under contracts NNH07AF81I and NNG06WF08I. Part of this work was supported by Chandra Cycle 10 Award AR9-0002X.

Flash X-ray

International Nuclear Information System (INIS)

Sato, Eiichi

2003-01-01

Generation of quasi-monochromatic X-ray by production of weakly ionized line plasma (flash X-ray), high-speed imaging by the X-ray and high-contrast imaging by the characteristic X-ray absorption are described. The equipment for the X-ray is consisted from the high-voltage power supply and condenser, turbo molecular pump, and plasma X-ray tube. The tube has a long linear anticathode to produce the line plasma and flash X-ray at 20 kA current at maximum. X-ray spectrum is measured by the imaging plate equipped in the computed radiography system after diffracted by a LiF single crystal bender. Cu anticathode generates sharp peaks of K X-ray series. The tissue images are presented for vertebra, rabbit ear and heart, and dog heart by X-ray fluoroscopy with Ce anticathode. Generation of K-orbit characteristic X-ray with extremely low bremsstrahung is to be attempted for medical use. (N.I.)

X-Ray Fluorescence Spectrometry. II Determination of Uranium in ores; Espectrometria de fluorescencia de Rayos X. II-Aplicacion a la determinacion de uranio en minerales

Energy Technology Data Exchange (ETDEWEB)

Bermudez Polonio, J; Crus Castillo, F. de la; Fernandez Cellini, R

1961-07-01

A method of analysis of uranium in ores by X-ray spectrometry was developed, using the internal standard technique. Strontium was found to be the most suitable internal standard for general use. A Norelco Philips X-ray fluorescent spectrometer was used in this work, equipped with a lithium fluoride crystal acting as a diffraction grating analyzer. The intensity of the uranium-L {alpha}{sub 1} spectral line is calculated and related to corresponding strontium-K{sub {alpha}} spectral line, both detected with a Scintillation Counter. (Author) 31 refs.

Preliminary comparison of grating-based and in-line phase contrast X-ray imaging with synchrotron radiation for mouse kidney at TOMCAT

International Nuclear Information System (INIS)

Sun, J; Liu, P; Xu, L X; Irvine, S; Pinzer, B; Stampanoni, M

2013-01-01

Phase contrast imaging has been demonstrated to be advantageous in revealing detailed structures inside biological specimens without contrast agents. Grating-based differential phase contrast (DPC) and in-line phase contrast (ILPC) X-ray imaging are the two modalities frequently used at the beamline of TOmographic Microscopy and Coherent rAdiology experimenTs (TOMCAT) at the Swiss Light Source (SLS). In this paper, we preliminarily compared the abilities of two types of phase contrast imaging in distinguishing micro structures in mouse kidneys. The 3D reconstructions showed that the microstructures in kidney, such as micro vessels and renal tubules, were displayed clearly with both imaging modalities. The two techniques may be viewed as complementary. For larger features with very small density variations DPC is the desirable method. In cases where dose and time limits may prohibit the multiple steps required for DPC, and when the focus is on finer features, the ILPC method may be considered as a more viable alternative. Moreover, high resolution ILPC images are comparable with histological results.

Observation of sagittal X-ray diffraction by surface acoustic waves in Bragg geometry.

Science.gov (United States)

Vadilonga, Simone; Zizak, Ivo; Roshchupkin, Dmitry; Evgenii, Emelin; Petsiuk, Andrei; Leitenberger, Wolfram; Erko, Alexei

2017-04-01

X-ray Bragg diffraction in sagittal geometry on a Y-cut langasite crystal (La 3 Ga 5 SiO 14 ) modulated by Λ = 3 µm Rayleigh surface acoustic waves was studied at the BESSY II synchrotron radiation facility. Owing to the crystal lattice modulation by the surface acoustic wave diffraction, satellites appear. Their intensity and angular separation depend on the amplitude and wavelength of the ultrasonic superlattice. Experimental results are compared with the corresponding theoretical model that exploits the kinematical diffraction theory. This experiment shows that the propagation of the surface acoustic waves creates a dynamical diffraction grating on the crystal surface, and this can be used for space-time modulation of an X-ray beam.

X-Ray

Science.gov (United States)

... enema. What you can expect During the X-ray X-rays are performed at doctors' offices, dentists' offices, ... as those using a contrast medium. Your child's X-ray Restraints or other techniques may be used to ...

X-ray phase-contrast tomosynthesis for improved breast tissue discrimination

International Nuclear Information System (INIS)

Schleede, Simone; Bech, Martin; Grandl, Susanne; Sztrókay, Aniko; Herzen, Julia; Mayr, Doris; Stockmar, Marco; Potdevin, Guillaume

2014-01-01

Purpose: Attenuation-based tomosynthesis has proven to successfully resolve the glandular tissue overlap present in mammography. However, the ability of tomosynthesis to differentiate tumorous and glandular tissue remains limited, due to the small differences in X-ray attenuation in breast tissue. One possibility to overcome this limitation and to further increase the diagnostic value of tomosynthesis exams, is the application of recently developed grating-based phase-contrast methods, which provide complementary information on the phase shift and the local scattering power of the sample. In this study, we report on first phase-contrast breast tomosynthesis results of a mastectomy sample slice with an invasive ductal carcinoma. Material and methods: A slice of a mastectomy sample with histologically proven invasive ductal cancer was imaged at the synchrotron radiation source ESRF (Grenoble, France). We used a two-grating interferometer setup at the ninth fractional Talbot distance and with an X-ray energy of 23 keV. In grating interferometry absorption, differential phase, and scattering images are recorded simultaneously. The tomosynthesis scan comprises 61 projections. Multimodal tomosynthesis results were reconstructed using a standard filtered back-projection approach. Our findings are supported by a comparison of tomographic views to histopathology. Results: Phase-contrast tomosynthesis combines the advantage of improved soft-tissue discrimination in phase-contrast imaging with the ability of tomosynthesis to provide a third dimension so that improved feature visibility is not hampered by superposition artifacts. Our results indicate superior diagnostic value due to the depth resolution supplied in tomosynthesis imaging; a region of necrotic tissue that is obscured in a projection image can clearly be depicted in one single tomosynthesis slice. Compared to absorption tomosynthesis alone, soft tissue contrast is significantly enhanced in phase

X-ray phase-contrast tomosynthesis for improved breast tissue discrimination.

Science.gov (United States)

Schleede, Simone; Bech, Martin; Grandl, Susanne; Sztrókay, Aniko; Herzen, Julia; Mayr, Doris; Stockmar, Marco; Potdevin, Guillaume; Zanette, Irene; Rack, Alexander; Weitkamp, Timm; Pfeiffer, Franz

2014-03-01

Attenuation-based tomosynthesis has proven to successfully resolve the glandular tissue overlap present in mammography. However, the ability of tomosynthesis to differentiate tumorous and glandular tissue remains limited, due to the small differences in X-ray attenuation in breast tissue. One possibility to overcome this limitation and to further increase the diagnostic value of tomosynthesis exams, is the application of recently developed grating-based phase-contrast methods, which provide complementary information on the phase shift and the local scattering power of the sample. In this study, we report on first phase-contrast breast tomosynthesis results of a mastectomy sample slice with an invasive ductal carcinoma. A slice of a mastectomy sample with histologically proven invasive ductal cancer was imaged at the synchrotron radiation source ESRF (Grenoble, France). We used a two-grating interferometer setup at the ninth fractional Talbot distance and with an X-ray energy of 23 keV. In grating interferometry absorption, differential phase, and scattering images are recorded simultaneously. The tomosynthesis scan comprises 61 projections. Multimodal tomosynthesis results were reconstructed using a standard filtered back-projection approach. Our findings are supported by a comparison of tomographic views to histopathology. Phase-contrast tomosynthesis combines the advantage of improved soft-tissue discrimination in phase-contrast imaging with the ability of tomosynthesis to provide a third dimension so that improved feature visibility is not hampered by superposition artifacts. Our results indicate superior diagnostic value due to the depth resolution supplied in tomosynthesis imaging; a region of necrotic tissue that is obscured in a projection image can clearly be depicted in one single tomosynthesis slice. Compared to absorption tomosynthesis alone, soft tissue contrast is significantly enhanced in phase-contrast tomosynthesis views, where fibrous structures

X-ray phase laminography with a grating interferometer using iterative reconstruction

International Nuclear Information System (INIS)

Harasse, Sébastien; Yashiro, Wataru; Momose, Atsushi

2012-01-01

X-ray phase computed laminography is performed using a Talbot interferometer and synchrotron radiation. An iterative reconstruction algorithm which includes prior information about limited support, range of values and sparsity of the imaged object has been developped. It allows the reconstruction of objects with an improved resolution of the unsampled frequencies, compared to the classical filtered backprojection. The imaging method, demonstrated for a nylon mesh sample and a leaf sample, shows promising results for the imaging of flat, laterally extended objects made of low absorbing elements.

Ronchi test for characterization of nanofocusing optics at a hard x-ray free-electron laser.

Science.gov (United States)

Nilsson, Daniel; Uhlén, Fredrik; Holmberg, Anders; Hertz, Hans M; Schropp, Andreas; Patommel, Jens; Hoppe, Robert; Seiboth, Frank; Meier, Vivienne; Schroer, Christian G; Galtier, Eric; Nagler, Bob; Lee, Hae Ja; Vogt, Ulrich

2012-12-15

We demonstrate the use of the classical Ronchi test to characterize aberrations in focusing optics at a hard x-ray free-electron laser. A grating is placed close to the focus and the interference between the different orders after the grating is observed in the far field. Any aberrations in the beam or the optics will distort the interference fringes. The method is simple to implement and can provide single-shot information about the focusing quality. We used the Ronchi test to measure the aberrations in a nanofocusing Fresnel zone plate at the Linac Coherent Light Source at 8.194 keV.

Synchrotron x-ray microbeam characteristics for x-ray fluorescence analysis

International Nuclear Information System (INIS)

Iida, Atsuo; Noma, Takashi

1995-01-01

X-ray fluorescence analysis using a synchrotron x-ray microprobe has become an indispensable technique for non-destructive micro-analysis. One of the most important parameters that characterize the x-ray microbeam system for x-ray fluorescence analysis is the beam size. For practical analysis, however, the photon flux, the energy resolution and the available energy range are also crucial. Three types of x-ray microbeam systems, including monochromatic and continuum excitation systems, were compared with reference to the sensitivity, the minimum detection limit and the applicability to various types of x-ray spectroscopic analysis. 16 refs., 5 figs

Lifting the veil on the X-ray universe

Science.gov (United States)

1999-11-01

. A multi-spectral space telescope The spacecraft carries three sets of science instruments, not only capable of making images of an X-ray source but also able to precisely distinguish the "colour" of the X-rays being viewed. At the prime focus of each of the telescopes are three European Photon Imaging Cameras. With silicon chips that can register extremely weak X-ray radiation, these advanced cameras are capable of detecting rapid variations in the intensity of a source. Grating structures at the exit of two mirror modules will reflect about half the incoming rays to a secondary focus, with its own cameras. This Reflection Grating Spectrometer will "fan out" the various wavelengths (much like a prism with visible light), and indicate in more detail the presence of individual elements, such as oxygen and iron. The third instrument aboard XMM is a conventional but very sensitive optical telescope. It will observe simultaneously the same regions as the X-ray telescopes but in the ultraviolet and visible wavelengths, giving astronomers complementary data about the X-ray sources being studied. In orbit, this 30-cm telescope will be as sensitive as a 4-m instrument on the Earth's surface. The mysteries of the X-ray sky XMM will explore the hidden depths of the Universe, its violent hotspots where stars and galaxies are formed, and where worlds and matter itself disappear. Much as the colour of a street lamp can indicate which gas it uses, the science instruments on board XMM will reveal the deepest secrets of X-ray objects, their chemical composition and temperatures - clues to the physical processes that are taking place. Astronomers will use XMM to resolve the mysteries of stars that exploded long ago as supernovae and whose remnants, glowing with X-rays, may be supplying material for new planets and stars. They will study regions of supernova remnants that are still hot and may hold the key to understanding the origin of the enigmatic cosmic rays that pervade the

X-ray sky

International Nuclear Information System (INIS)

Gruen, M.; Koubsky, P.

1977-01-01

The history is described of the discoveries of X-ray sources in the sky. The individual X-ray detectors are described in more detail, i.e., gas counters, scintillation detectors, semiconductor detectors, and the principles of X-ray spectrometry and of radiation collimation aimed at increased resolution are discussed. Currently, over 200 celestial X-ray sources are known. Some were identified as nebulae, in some pulsations were found or the source was identified as a binary star. X-ray bursts of novae were also observed. The X-ray radiation is briefly mentioned of spherical star clusters and of extragalactic X-ray sources. (Oy)

Novel X-ray phase-contrast tomography method for quantitative studies of heat induced structural changes in meat

DEFF Research Database (Denmark)

Miklos, Rikke; Nielsen, Mikkel Schou; Einarsdottir, Hildur

2014-01-01

The objective of this study was to evaluate the use of X-ray phase-contrast tomography combined with 3D image segmentation to investigate the heat induced structural changes in meat. The measurements were performed at the Swiss synchrotron radiation light source using a grating interferometric...... and separated into a water phase and a gel phase formed by the sarcoplasmic proteins in the exudate. The results show that X-ray phase contrast tomography offers unique possibilities in studies both the meat structure and the different meat component such as water, fat, connective tissue and myofibrils...

X-ray reflectivity of cobalt and titanium in the vicinity of the Lsub(2,3) absorption edges

International Nuclear Information System (INIS)

Bremer, J.; Kaihola, L.; Keski-Kuha, R.

1980-01-01

X-ray reflectivity across cobalt and titanium Lsub(2,3) absorption edges was measured as a function of energy by means of continuous radiation from a tungsten anode in a grating spectrometer. The real and imaginary parts of the refractive index were obtained from the absorption curves and an exact Kramers-Kronig analysis. A measured fine structure in the reflected intensities was interpreted as an effect of white lines in the absorption spectra. The x-ray intensity was calculated as a function of energy by means of the Fresnel formula. (author)

X-ray astronomy

International Nuclear Information System (INIS)

Culhane, J.L.; Sanford, P.W.

1981-01-01

X-ray astronomy has been established as a powerful means of observing matter in its most extreme form. The energy liberated by sources discovered in our Galaxy has confirmed that collapsed stars of great density, and with intense gravitational fields, can be studied by making observations in the X-ray part of the electromagnetic spectrum. The astronomical objects which emit detectable X-rays include our own Sun and extend to quasars at the edge of the Universe. This book describes the history, techniques and results obtained in the first twenty-five years of exploration. Space rockets and satellites are essential for carrying the instruments above the Earth's atmosphere where it becomes possible to view the X-rays from stars and nebulae. The subject is covered in chapters, entitled: the birth of X-ray astronomy; the nature of X-radiation; X-rays from the Sun; solar-flare X-rays; X-rays from beyond the solar system; supernovae and their remnants; X-rays from binary stars; white dwarfs and neutron stars; black holes; X-rays from galaxies and quasars; clusters of galaxies; the observatories of the future. (author)

Rocket Experiment Demonstration of a Soft X-ray Polarimeter

Science.gov (United States)

Marshall, Herman

This proposal is the lead proposal. Boston University will submit, via NSPIRES, a Co-I proposal, per instructions for Suborbital proposals for multiple-award. Our scientific goal of the Rocket Experiment Demonstration of a Soft X-ray Polarimeter (REDSoX Polarimeter) is to make the first measurement of the linear X-ray polarization of an extragalactic source in the 0.2-0.8 keV band. The first flight of the REDSoX Polarimeter would target Mk 421, which is commonly modeled as a highly relativistic jet aimed nearly along the line of sight. Such sources are likely to be polarized at a level of 30-60%, so the goal is to obtain a significant detection even if it is as low as 10%. Significant revisions to the models of jets emanating from black holes at the cores of active galaxies would be required if the polarization fraction lower than 10%. We employ multilayer-coated mirrors as Bragg reflectors at the Brewster angle. By matching to the dispersion of a spectrometer, one may take advantage of high multilayer reflectivities and achieve polarization modulation factors over 90%. Using replicated foil mirrors from MSFC and gratings made at MIT, we construct a spectrometer that disperses to three laterally graded multilayer mirrors (LGMLs). The lateral grading changes the wavelength of the Bragg peak for 45 degree reflections linearly across the mirror, matching the dispersion of the spectrometer. By dividing the entrance aperture into six equal sectors, pairs of blazed gratings from opposite sectors are oriented to disperse to the same LGML. The position angles for the LGMLs are 120 degrees to each other. CCD detectors then measure the intensities of the dispersed spectra after reflection and polarizing by the LGMLs, giving the three Stokes parameters needed to determine the source polarization. We will rely on components whose performance has been verified in the laboratory or in space. The CCD detectors are based on Chandra and Suzaku heritage. The mirror fabrication team

On-board event processing algorithms for a CCD-based space borne X-ray spectrometer

International Nuclear Information System (INIS)

Chun, H.J.; Bowles, J.A.; Branduardi-Raymont, G.; Gowen, R.A.

1996-01-01

This paper describes two alternative algorithms which are applied to reduce the telemetry requirements for a Charge Coupled Device (CCD) based, space-borne, X-ray spectrometer by on-board reconstruction of the X-ray events split over two or more adjacent pixels. The algorithms have been developed for the Reflection Grating Spectrometer (RGS) on the X-ray multi-mirror (XMM) mission, the second cornerstone project in the European Space Agency's Horizon 2000 programme. The overall instrument and some criteria which provide the background of the development of the algorithms, implemented in Tartan ADA on an MA31750 microprocessor, are described. The on-board processing constraints and requirements are discussed, and the performances of the algorithms are compared. Test results are presented which show that the recursive implementation is faster and has a smaller executable file although it uses more memory because of its stack requirements. (orig.)

Visualization of neonatal lung injury associated with mechanical ventilation using x-ray dark-field radiography

Science.gov (United States)

Yaroshenko, Andre; Pritzke, Tina; Koschlig, Markus; Kamgari, Nona; Willer, Konstantin; Gromann, Lukas; Auweter, Sigrid; Hellbach, Katharina; Reiser, Maximilian; Eickelberg, Oliver; Pfeiffer, Franz; Hilgendorff, Anne

2016-04-01

Mechanical ventilation (MV) and supplementation of oxygen-enriched gas, often needed in postnatal resuscitation procedures, are known to be main risk factors for impaired pulmonary development in the preterm and term neonates. Unfortunately, current imaging modalities lack in sensitivity for the detection of early stage lung injury. The present study reports a new imaging approach for diagnosis and staging of early lung injury induced by MV and hyperoxia in neonatal mice. The imaging method is based on the Talbot-Lau x-ray grating interferometry that makes it possible to quantify the x-ray small-angle scattering on the air-tissue interfaces. This so-called dark-field signal revealed increasing loss of x-ray small-angle scattering when comparing images of neonatal mice undergoing hyperoxia and MV-O2 with animals kept at room air. The changes in the dark field correlated well with histologic findings and provided superior differentiation than conventional x-ray imaging and lung function testing. The results suggest that x-ray dark-field radiography is a sensitive tool for assessing structural changes in the developing lung. In the future, with further technical developments x-ray dark-field imaging could be an important tool for earlier diagnosis and sensitive monitoring of lung injury in neonates requiring postnatal oxygen or ventilator therapy.

Skull x-ray

Science.gov (United States)

X-ray - head; X-ray - skull; Skull radiography; Head x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

Neck x-ray

Science.gov (United States)

X-ray - neck; Cervical spine x-ray; Lateral neck x-ray ... There is low radiation exposure. X-rays are monitored so that the lowest amount of radiation is used to produce the image. Pregnant women and ...

High-Resolution X-Ray Spectroscopy of Galactic Supernova Remnants

Directory of Open Access Journals (Sweden)

Satoru Katsuda

2014-12-01

Full Text Available High-resolution X-ray spectroscopy of Galactic supernova remnants (SNRs, based on grating spectrometers onboard XMM-Newton and Chandra, has been revealing a variety of new astrophysical phenomena. Broadened oxygen lines for a northwestern compact knot in SN 1006 clearly show a high oxygen temperature of ~300 keV. The high temperature together with a lower electron temperature (kTe ~ 1 keV can be reasonably interpreted as temperature non-equilibration between electrons and oxygen behind a collisionless shock. An ejecta knot in the Puppis A SNR shows blueshifted line emission by ~ 1500kms-1. The line widths are fairly narrow in contrast to the SN 1006's knot; an upper limit of 0.9 eV is obtained for O VIII Lyα, which translates to an oxygen temperature of kTO < 30 keV. The low temperature suggests that the knot was heated by a reverse shock whose velocity is 4 times slower than that of a forward shock. Anomalous intensity ratios in O VII Heα lines, i.e., a stronger forbidden line than a resonance line, is found in a cloud-shock interaction region in Puppis A. The line ratio can be best explained by the charge-exchange emission that should arise at interfaces between the cold/warm clouds and the hot plasma. There are several other targets for which we plan to analyze high-quality grating data prior to the operation of the soft X-ray spectrometer onboard Astro-H.

X-ray filter for chest X-rays

International Nuclear Information System (INIS)

Ferlic, D.J.

1984-01-01

A description is given of an X-ray filter comprised of a sheet of radiation absorbing material with an opening corresponding to the spine and central portion of the heart. The upper portion of the filter exhibits a relatively narrow opening which becomes gradually wider toward the lower portion of the filter. This filter will permit an acceptable density level of x-ray exposure for the lungs while allowing a higher level of x-ray exposure for the mediastinum areas of the body. (author)

Time-resolved X-ray transmission microscopy on magnetic microstructures

International Nuclear Information System (INIS)

Puzic, Aleksandar

2007-01-01

Three excitation schemes were designed for stroboscopic imaging of magnetization dynamics with time-resolved magnetic transmission X-ray microscopy (TR-MTXM). These techniques were implemented into two types of X-ray microscopes, namely the imaging transmission X-ray microscope (ITXM) and the scanning transmission X-ray microscope (STXM), both installed at the electron storage ring of the Advanced Light Source in Berkeley, USA. Circular diffraction gratings (Fresnel zone plates) used in both microscopes as focusing and imaging elements presently allow for lateral resolution down to 30 nm. Magnetic imaging is performed by using the X-ray magnetic circular dichroism (XMCD) as element specific contrast mechanism. The developed methods have been successfully applied to the experimental investigation of magnetization dynamics in ferromagnetic microstructures. A temporal resolution well below 100 ps was achieved. A conventional pump-probe technique was implemented first. The dynamic response of the magnetization excited by a broadband pulsed magnetic field was imaged spatially resolved using focused X-ray flashes. As a complementary method, the spatially resolved ferromagnetic resonance (SR-FMR) technique was developed for experimental study of magnetization dynamics in the frequency domain. As a third excitation mode, the burst excitation was implemented. The performance and efficiency of the developed methods have been demonstrated by imaging the local magnetization dynamics in laterally patterned ferromagnetic thin-film elements and three-layer stacks. The existence of multiple eigenmodes in the excitation spectra of ferromagnetic microstructures has been verified by using the pump-probe technique. Magnetostatic spin waves were selectively excited and detected with a time resolution of 50 ps using the SR-FMR technique. Thorough analysis of 20 in most cases independently prepared samples has verified that vortices which exhibit a low-amplitude switching of their core

X-ray optics and X-ray microscopes: new challenges

International Nuclear Information System (INIS)

Susini, J.

2004-01-01

Soon after the discovery of X-rays in 1895 by W. Roentgen, it became rapidly clear that the methods traditionally used in the visible light regime, namely refraction, diffraction and reflection were difficult to apply for X-ray optics. The physical origins of these difficulties are closely linked to the very nature of interaction of X-rays with matter. The small deviation δ of the refractive index of condensed matter from unity makes it difficult to extend refraction-based optics from the optical spectral region to the X-ray region because the refraction angle is proportional to δ. Similarly it is very challenging to extend diffraction-based focusing techniques to X-rays because the diffraction angle scales inversely with wavelength. Finally, the use of reflection-based optics is also limited by the very small critical angle for total reflection. All those fundamental limitations prevented for almost one century, the development of X-ray microscopy whereas electron microscopy became a standard tool. In the past twenty years, interests for X-ray microscopy revived, mainly because of several major advances in X-ray sources and X-ray optics. X-ray microscopy techniques are now emerging as powerful and complementary tools for submicron investigations. Soft X-ray microscopes offer traditionally the possibility to form direct images of thick hydrated biological material in near-native environment, at a spatial resolution well beyond that achievable with visible light microscopy. Natural contrast is available in the soft X-ray region, in the so-called ''water-window'', due to the presence of absorption edges of the major constituents (C,N,O). Recent advances in manufacturing techniques have enlarged the accessible energy range of micro-focussing optics and offer new applications in a broad range of disciplines. X-ray microscopy in the 1 - 30 keV energy range is better suited for fluorescence to map trace elements, tomography for 3D imaging and micro-diffraction. The

X-ray filter for chest x-rays

International Nuclear Information System (INIS)

Ferlic, D.J.

1984-01-01

Filter for use in medical x-ray apparatus to permit higher intensity x-ray exposure in the heart and mediastinum area while maintaining a normal level of x-ray exposure in other areas of the body, particlarly in the lung area. The filter comprises a sheet of radiation absorbing material having an opening therein, said opening corresponding to the spine and central portion of the heart. Accordingly, the upper portion of the filter exhibits a relatively narrow opening which becomes gradually wider toward the lower portion of the filter

Design of scanning motion control system for high-energy X-ray industrial CT

International Nuclear Information System (INIS)

Duan Liming

2008-01-01

A scanning motion control system was developed for the high-energy X-ray industrial computerized tomography (CT). The system consists of an industrial control computer, a counter card, a control card, servo drivers, servo motors, working platforms, gratings and control software. Based on windows driver model(WDM) mode, the composition of the driver pro- gram for the system was studied. Took the motor control card as an example, the method to develop the driver program was researched, and the intercourse process between the device driver program and the user-program was analyzed. The real-time control of the system was implemented using the WDM driver. The real-time performance and reliability of the system can satisfy the requirement of high-energy X-ray industrial CT. (authors)

Computer-aided diagnosis of pulmonary diseases using x-ray darkfield radiography

International Nuclear Information System (INIS)

Einarsdóttir, Hildur; Larsen, Rasmus; Ersbøll, Bjarne Kjær; Yaroshenko, Andre; Velroyen, Astrid; Bech, Martin; Pfeiffer, Franz; Hellbach, Katharina; Auweter, Sigrid; Meinel, Felix G; Reiser, Maximilian; Yildirim, Önder; Eickelberg, Oliver

2015-01-01

In this work we develop a computer-aided diagnosis (CAD) scheme for classification of pulmonary disease for grating-based x-ray radiography. In addition to conventional transmission radiography, the grating-based technique provides a dark-field imaging modality, which utilizes the scattering properties of the x-rays. This modality has shown great potential for diagnosing early stage emphysema and fibrosis in mouse lungs in vivo. The CAD scheme is developed to assist radiologists and other medical experts to develop new diagnostic methods when evaluating grating-based images. The scheme consists of three stages: (i) automatic lung segmentation; (ii) feature extraction from lung shape and dark-field image intensities; (iii) classification between healthy, emphysema and fibrosis lungs. A study of 102 mice was conducted with 34 healthy, 52 emphysema and 16 fibrosis subjects. Each image was manually annotated to build an experimental dataset. System performance was assessed by: (i) determining the quality of the segmentations; (ii) validating emphysema and fibrosis recognition by a linear support vector machine using leave-one-out cross-validation. In terms of segmentation quality, we obtained an overlap percentage (Ω) 92.63  ±  3.65%, Dice Similarity Coefficient (DSC) 89.74  ±  8.84% and Jaccard Similarity Coefficient 82.39  ±  12.62%. For classification, the accuracy, sensitivity and specificity of diseased lung recognition was 100%. Classification between emphysema and fibrosis resulted in an accuracy of 93%, whilst the sensitivity was 94% and specificity 88%. In addition to the automatic classification of lungs, deviation maps created by the CAD scheme provide a visual aid for medical experts to further assess the severity of pulmonary disease in the lung, and highlights regions affected. (paper)

X-ray geometrical smoothing effect in indirect x-ray-drive implosion

International Nuclear Information System (INIS)

Mochizuki, Takayasu; Sakabe, Shuji; Yamanaka, Chiyoe

1983-01-01

X-ray geometrical smoothing effect in indirect X-ray drive pellet implosion for inertial confinement fusion has been numerically analyzed. Attainable X-ray driven ablation pressure has been found to be coupled with X-ray irradiation uniformity. (author)

Different X-ray spectral evolution for black hole X-ray binaries in dual tracks of radio-X-ray correlation

International Nuclear Information System (INIS)

Cao, Xiao-Feng; Wu, Qingwen; Dong, Ai-Jun

2014-01-01

Recently, an 'outlier' track of radio-X-ray correlation was found, which is much steeper than the former universal correlation, where dual tracks were speculated to be triggered by different accretion processes. In this work, we test this issue by exploring hard X-ray spectral evolution in four black-hole X-ray binaries with multiple, quasi-simultaneous radio and X-ray observations. First, we find that hard X-ray photon indices, Γ, are negatively and positively correlated with X-ray fluxes when the X-ray flux, F 3-9 keV , is below and above a critical flux, F X, crit , which are consistent with predictions of the advection-dominated accretion flow and the disk-corona model, respectively. Second, and most importantly, we find that the radio-X-ray correlations are also clearly different when the X-ray fluxes are higher and lower than the critical flux as defined by X-ray spectral evolution. The data points with F 3-9 keV ≳ F X, crit have a steeper radio-X-ray correlation (F X ∝F R b and b ∼ 1.1-1.4), which roughly forms the ''outlier'' track. However, the data points with anti-correlation of Γ – F 3-9 keV either stay in the universal track with b ∼ 0.61 or stay in the transition track (from the universal to 'outlier' tracks or vice versa). Therefore, our results support that the universal and ''outlier'' tracks of radio-X-ray correlations are regulated by radiatively inefficient and radiatively efficient accretion model, respectively.

Comparison of x-ray output of inverter-type x-ray equipment

International Nuclear Information System (INIS)

Asano, Hiroshi; Miyake, Hiroyuki; Yamamoto, Keiichi

2000-01-01

The x-ray output of 54 inverter-type x-ray apparatuses used at 18 institutions was investigated. The reproducibility and linearity of x-ray output and variations among the x-ray equipment were evaluated using the same fluorescence meter. In addition, the x-ray apparatuses were re-measured using the same non-invasive instrument to check for variations in tube voltage, tube current, and irradiation time. The non-invasive instrument was calibrated by simultaneously obtaining measurements with an invasive instrument, employing the tube voltage and current used for the invasive instrument, and the difference was calculated. Reproducibility of x-ray output was satisfactory for all x-ray apparatuses. The coefficient of variation was 0.04 or less for irradiation times of 5 ms or longer. In 84.3% of all x-ray equipment, variation in the linearity of x-ray output was 15% or less for an irradiation time of 5 ms. However, for all the apparatuses, the figure was 50% when irradiation time was the shortest (1 to 3 ms). Variation in x-ray output increased as irradiation time decreased. Variation in x-ray output ranged between 1.8 and 2.5 compared with the maximum and minimum values, excluding those obtained at the shortest irradiation time. The relative standard deviation ranged from ±15.5% to ±21.0%. The largest variation in x-ray output was confirmed in regions irradiated for the shortest time, with smaller variations observed for longer irradiation times. The major factor responsible for variation in x-ray output in regions irradiated for 10 ms or longer, which is a relatively long irradiation time, was variation in tube current. Variation in tube current was slightly greater than 30% at maximum, with an average value of 7% compared with the preset tube current. Variations in x-ray output in regions irradiated for the shortest time were due to photographic effects related to the rise and fall times of the tube voltage waveform. Accordingly, in order to obtain constant x-ray

Chest X-Ray

Medline Plus

Full Text Available ... about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed x-ray exams and use a very small dose of ... of the inside of the chest. A chest x-ray is used to evaluate the lungs, heart and ...

Design of a wideband multilayer grating spectrometer for the study of electronic structure of thin-film CIS solar cells

International Nuclear Information System (INIS)

Imazono, Takashi; Koike, Masato; Kuramoto, Satoshi; Nagano, Tetsuya; Koeda, Masaru; Moriya, Naoji

2014-01-01

A soft x-ray emission spectrometer equipped with a wideband Ni/C multilayer-coated laminar-type varied-line-spacing holographic grating is designed to analyze the electronic structure in thin-film copper indium selenide (CIS) solar cells nondestructively by soft x-ray emission spectroscopy. The spectrometer equipped with the multilayer grating thus designed allows us to detect the L emission lines of Cu, In, and Se simultaneously from a CIS absorber layer in the 1–3.5 keV range at a constant angle of incidence. (author)

SOFT X-RAY SPECTROSCOPY OF THE CYGNUS LOOP SUPERNOVA REMNANT

Energy Technology Data Exchange (ETDEWEB)

Oakley, Phil [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Ave., 37-582F, Cambridge, MA 02139 (United States); McEntaffer, Randall [Department of Physics and Astronomy, Van Allen Hall, University of Iowa, Iowa City, IA 52242 (United States); Cash, Webster, E-mail: Oakley@mit.edu [Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO 80309 (United States)

2013-03-20

We present the results of a suborbital rocket flight whose scientific target was the Cygnus Loop Supernova Remnant. The payload consists of wire grid collimators, off-plane grating arrays, and gaseous electron multiplier (GEM) detectors. The system is designed for spectral measurements in the 17-107 A bandpass with a resolution up to {approx}60 ({lambda}/{Delta}{lambda}). The Extended X-ray Off-plane Spectrometer (EXOS) was launched on a Terrier-Black Brant rocket on 2009 November 13 from White Sands Missile Range and obtained 340 s of useable scientific data. The X-ray emission is dominated by O VII and O VIII, including the He-like O VII triplet at {approx}22 A. Another emission feature at {approx}45 A is composed primarily of Si XI and Si XII. The best-fit model to this spectrum is an equilibrium plasma model at a temperature of log(T) = 6.4 (0.23 keV).

X-ray Tomographic Microscopy at TOMCAT

Energy Technology Data Exchange (ETDEWEB)

Marone, F; Hintermueller, C; McDonald, S; Abela, R; Mikuljan, G; Isenegger, A; Stampanoni, M, E-mail: federica.marone@psi.c [Swiss Light Source, Paul Scherrer Institut, 5232 Villigen (Switzerland)

2009-09-01

Synchrotron-based X-ray Tomographic Microscopy is a powerful technique for fast non-destructive, high resolution quantitative volumetric investigations on diverse samples. At the TOMCAT (TOmographic Microscopy and Coherent rAdiology experimenTs) beamline at the Swiss Light Source, synchrotron light is delivered by a 2.9 T superbend. The main optical component, a Double Crystal Multilayer Monochromator, covers an energy range between 8 and 45 keV. The standard TOMCAT detector offers field of views ranging from 0.75x0.75 mm{sup 2} up to 12.1x12.1 mm{sup 2} with a pixel size of 0.37 {mu}m and 5.92 {mu}m, respectively. In addition to routine measurements, which exploit the absorption contrast, the high coherence of the source also enables phase contrast tomography, implemented with two complementary techniques (Modified Transport of Intensity approach and Grating Interferometry). Typical acquisition times for a tomogram are in the order of few minutes, ensuring high throughput and allowing for semi-dynamical investigations. Raw data are automatically post-processed online and full reconstructed volumes are available shortly after a scan with minimal user intervention.

A Single-Element Plane Grating Monochromator

Directory of Open Access Journals (Sweden)

Michael C. Hettrick

2016-01-01

Full Text Available Concerted rotations of a self-focused varied line-space diffraction grating about its groove axis and surface normal define a new geometric class of monochromator. Defocusing is canceled, while the scanned wavelength is reinforced at fixed conjugate distances and horizontal deviation angle. This enables high spectral resolution over a wide band, and is of particular advantage at grazing reflection angles. A new, rigorous light-path formulation employs non-paraxial reference points to isolate the lateral ray aberrations, with those of power-sum ≤ 3 explicitly expanded for a plane grating. Each of these 14 Fermat equations agrees precisely with the value extracted from numerical raytrace simulations. An example soft X-ray design (6° deviation angle and 2 × 4 mrad aperture attains a resolving power > 25 , 000 over a three octave scan range. The proposed rotation scheme is not limited to plane surfaces or monochromators, providing a new degree of freedom in optical design.

Wide field X-ray telescopes: Detecting X-ray transients/afterglows related to gamma ray bursts

International Nuclear Information System (INIS)

Hudec, Rene; Pina, Ladislav; Inneman, Adolf; Gorenstein, Paul; Rezek, Tomas

1999-01-01

The recent discovery of X-ray afterglows of GRBs opens the possibility of analyses of GRBs by their X-ray detections. However, imaging X-ray telescopes in current use mostly have limited field of view. Alternative X-ray optics geometries achieving very large fields of view have been theoretically suggested in the 70ies but not constructed and used so far. We review the geometries and basic properties of the wide-field X-ray optical systems based on one- and two-dimensional lobster-eye geometry and suggest technologies for their development and construction. First results of the development of double replicated X-ray reflecting flats for use in one-dimensional X-ray optics of lobster eye type are presented and discussed. Optimum strategy for locating GRBs upon their X-ray counterparts is also presented and discussed

Diffraction efficiency of radially-profiled off-plane reflection gratings

Science.gov (United States)

Miles, Drew M.; Tutt, James H.; DeRoo, Casey T.; Marlowe, Hannah; Peterson, Thomas J.; McEntaffer, Randall L.; Menz, Benedikt; Burwitz, Vadim; Hartner, Gisela; Laubis, Christian; Scholze, Frank

2015-09-01

Future X-ray missions will require gratings with high throughput and high spectral resolution. Blazed off-plane reflection gratings are capable of meeting these demands. A blazed grating profile optimizes grating efficiency, providing higher throughput to one side of zero-order on the arc of diffraction. This paper presents efficiency measurements made in the 0.3 - 1.5 keV energy band at the Physikalisch-Technische Bundesanstalt (PTB) BESSY II facility for three holographically-ruled gratings, two of which are blazed. Each blazed grating was tested in both the Littrow configuration and anti-Littrow configuration in order to test the alignment sensitivity of these gratings with regard to throughput. This paper outlines the procedure of the grating experiment performed at BESSY II and discuss the resulting efficiency measurements across various energies. Experimental results are generally consistent with theory and demonstrate that the blaze does increase throughput to one side of zero-order. However, the total efficiency of the non-blazed, sinusoidal grating is greater than that of the blazed gratings, which suggests that the method of manufacturing these blazed profiles fails to produce facets with the desired level of precision. Finally, evidence of a successful blaze implementation from first diffraction results of prototype blazed gratings produce via a new fabrication technique at the University of Iowa are presented.

Takagi-Taupin description of x-ray dynamical diffraction from diffractive optics with large numerical aperture

International Nuclear Information System (INIS)

Yan Hanfei; Maser, Joerg; Macrander, Albert; Shen Qun; Vogt, Stefan; Stephenson, G. Brian; Kang, Hyon Chol

2007-01-01

We present a formalism of x-ray dynamical diffraction from volume diffractive optics with large numerical aperture and high aspect ratio, in an analogy to the Takagi-Taupin equations [Acta Crystallogr. 15, 1311 (1962); Bull. Soc. Fr. Mineral. Crystallogr. 87, 469 (1964)] for strained single crystals. We derive a set of basic equations for dynamical diffraction from volume diffractive optics, which enable us to study the focusing property of these optics with various grating profiles. We study volume diffractive optics that satisfy the Bragg condition to various degrees, namely, flat, tilted, and wedged geometries, and derive the curved geometries required for ultimate focusing. We show that the curved geometries satisfy both the Bragg condition everywhere and phase requirement for point focusing and effectively focus hard x rays to a scale close to the wavelength. Our calculations were made for an x-ray wavelength of 0.064 nm (19.5 keV)

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....

CHANDRA HIGH-ENERGY TRANSMISSION GRATING SPECTRUM OF AE AQUARII

International Nuclear Information System (INIS)

Mauche, Christopher W.

2009-01-01

The nova-like cataclysmic binary AE Aqr, which is currently understood to be a former supersoft X-ray binary and current magnetic propeller, was observed for over two binary orbits (78 ks) in 2005 August with the High-Energy Transmission Grating (HETG) on board the Chandra X-ray Observatory. The long, uninterrupted Chandra observation provides a wealth of details concerning the X-ray emission of AE Aqr, many of which are new and unique to the HETG. First, the X-ray spectrum is that of an optically thin multi-temperature thermal plasma; the X-ray emission lines are broad, with widths that increase with the line energy from σ ∼ 1 eV (510 km s -1 ) for O VIII to σ ∼ 5.5 eV (820 km s -1 ) for Si XIV; the X-ray spectrum is reasonably well fit by a plasma model with a Gaussian emission measure distribution that peaks at log T(K) = 7.16, has a width σ = 0.48, an Fe abundance equal to 0.44 times solar, and other metal (primarily Ne, Mg, and Si) abundances equal to 0.76 times solar; and for a distance d = 100 pc, the total emission measure EM = 8.0 x 10 53 cm -3 and the 0.5-10 keV luminosity L X = 1.1 x 10 31 erg s -1 . Second, based on the f/(i + r) flux ratios of the forbidden (f), intercombination (i), and recombination (r) lines of the Heα triplets of N VI, O VII, and Ne IX measured by Itoh et al. in the XMM-Newton Reflection Grating Spectrometer spectrum and those of O VII, Ne IX, Mg XI, and Si XIII in the Chandra HETG spectrum, either the electron density of the plasma increases with temperature by over three orders of magnitude, from n e ∼ 6 x 10 10 cm -3 for N VI [log T(K) ∼ 6] to n e ∼ 1 x 10 14 cm -3 for Si XIII [log T(K) ∼ 7], and/or the plasma is significantly affected by photoexcitation. Third, the radial velocity of the X-ray emission lines varies on the white dwarf spin phase, with two oscillations per spin cycle and an amplitude K ∼ 160 km s -1 . These results appear to be inconsistent with the recent models of Itoh et al., Ikhsanov, and

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.

Scanning transmission x-ray microscope for materials science spectromicroscopy at the ALS

Energy Technology Data Exchange (ETDEWEB)

Warwick, T.; Seal, S.; Shin, H. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

The brightness of the Advanced Light Source will be exploited by several new instruments for materials science spectromicroscopy over the next year or so. The first of these to become operational is a scanning transmission x-ray microscope with which near edge x-ray absorption spectra (NEXAFS) can be measured on spatial features of sub-micron size. Here the authors describe the instrument as it is presently implemented, its capabilities, some studies made to date and the developments to come. The Scanning Transmission X-ray Microscope makes use of a zone plate lens to produce a small x-ray spot with which to perform absorption spectroscopy through thin samples. The x-ray beam from ALS undulator beamline 7.0 emerges into the microscope vessel through a silicon nitride vacuum window 160nm thick and 300{mu}m square. The vessel is filled with helium at atmospheric pressure. The zone plate lens is illuminated 1mm downstream from the vacuum window and forms an image in first order of a pinhole which is 3m upstream in the beamline. An order sorting aperture passes the first order converging light and blocks the unfocused zero order. The sample is at the focus a few mm downstream of the zone plate and mounted from a scanning piezo stage which rasters in x and y so that an image is formed, pixel by pixel, by an intensity detector behind the sample. Absorption spectra are measured point-by-point as the photon energy is scanned by rotating the diffraction grating in the monochromator and changing the undulator gap.

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 ...

Bone X-Ray (Radiography)

Medline Plus

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

Bone X-Ray (Radiography)

Science.gov (United States)

... 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 ...

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 ...

CRL X-ray tube

International Nuclear Information System (INIS)

Kolchevsky, N.N.; Petrov, P.V.

2015-01-01

A novel types of X-ray tubes with refractive lenses are proposed. CRL-R X-ray tube consists of Compound Refractive Lens- CRL and Reflection X-ray tube. CRL acts as X-ray window. CRL-T X-ray consists of CRL and Transmission X-ray tube. CRL acts as target for electron beam. CRL refractive lens acts as filter, collimator, waveguide and focusing lens. Properties and construction of the CRL X-ray tube are discussed. (authors)

Bone X-Ray (Radiography)

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

Novel X-ray telescopes for wide-field X-ray monitoring

International Nuclear Information System (INIS)

Hudec, R.; Inneman, A.; Pina, L.; Sveda, L.

2005-01-01

We report on fully innovative very wide-field of view X-ray telescopes with high sensitivity as well as large field of view. The prototypes are very promising, allowing the proposals for space projects with very wide-field Lobster-eye X-ray optics to be considered. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study and to understand various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. The Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science

Advanced X-Ray Telescope Mirrors Provide Sharpest Focus Ever

Science.gov (United States)

1997-03-01

's science mission. "We will observe X-rays generated when stars are torn apart by the incredibly strong gravity around massive black holes in the centers of galaxies," added Tananbaum. On a larger scale, the telescope will play a vital role in answering fundamental questions about the universe. "The superior quality of the mirrors will allow us to see and measure the details of hot gas clouds in clusters of galaxies, giving us a much better idea of the age and size of the universe," said Dr. Leon Van Speybroeck, Telescope Scientist at the Smithsonian Observatory. "These same observations also will measure the amount of dark matter present, providing unique insight into one of nature's great puzzles," said Van Speybroeck. A second phase of testing is now underway at Marshall. Calibration of the observatory's science instruments began in mid-February. "This phase of testing," said Weisskopf, "includes two focal plane instruments and two sets of gratings used to analyze images and energy distributions from cosmic sources seen by the telescope." Working around the clock, test teams are taking measurements and studying results. "It is very exciting," said Weisskopf. "With more than 1,200 measurements taken, there is already a tremendous amount of information for study." The calibration process will end around late April. The mirror assembly then will be shipped to TRW Space and Electronics Group, Redondo Beach, CA -- NASA's prime contractor for the program -- for integration into the spacecraft. The science instruments will remain at Marshall for several more weeks of testing before being shipped to Ball Aerospace and Technologies Corporation in Boulder, CO, where they will be integrated into the science instrument module before being shipped to TRW. The Advanced X-ray Astrophysics Facility is scheduled for launch in August 1998 and will join NASA's Hubble Space Telescope and Compton Gamma-ray Observatory in exploring the universe. Marshall manages development of the observatory

Bone X-Ray (Radiography)

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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 ...

Perfect-crystal x-ray optics to treat x-ray coherence

International Nuclear Information System (INIS)

Yamazaki, Hiroshi; Ishikawa, Tetsuya

2007-01-01

X-ray diffraction of perfect crystals, which serve as x-ray monochromator and collimator, modifies coherence properties of x-ray beams. From the time-dependent Takagi-Taupin equations that x-ray wavefields obey in crystals, the reflected wavefield is formulated as an integral transform of a general incident wavefield with temporal and spatial inhomogeneity. A reformulation of rocking-curve profiles from the field solution of the Takagi-Taupin equations allows experimental evaluation of the mutual coherence function of x-ray beam. The rigorous relationship of the coherence functions between before and after reflection clarifies how the coherence is transferred by a crystal. These results will be beneficial to developers of beamline optics for the next generation synchrotron sources. (author)

X-ray spectrometer spectrograph telescope system. [for solar corona study

Science.gov (United States)

Bruner, E. C., Jr.; Acton, L. W.; Brown, W. A.; Salat, S. W.; Franks, A.; Schmidtke, G.; Schweizer, W.; Speer, R. J.

1979-01-01

A new sounding rocket payload that has been developed for X-ray spectroscopic studies of the solar corona is described. The instrument incorporates a grazing incidence Rowland mounted grating spectrograph and an extreme off-axis paraboloic sector feed system to isolate regions of the sun of order 1 x 10 arc seconds in size. The focal surface of the spectrograph is shared by photographic and photoelectric detection systems, with the latter serving as a part of the rocket pointing system control loop. Fabrication and alignment of the optical system is based on high precision machining and mechanical metrology techniques. The spectrograph has a resolution of 16 milliangstroms and modifications planned for future flights will improve the resolution to 5 milliangstroms, permitting line widths to be measured.

X-ray scattering in X-ray fluorescence spectra with X-ray tube excitation - Modelling, experiment, and Monte-Carlo simulation

International Nuclear Information System (INIS)

Hodoroaba, V.-D.; Radtke, M.; Vincze, L.; Rackwitz, V.; Reuter, D.

2010-01-01

X-ray scattering may contribute significantly to the spectral background of X-ray fluorescence (XRF) spectra. Based on metrological measurements carried out with a scanning electron microscope (SEM) having attached a well characterised X-ray source (polychromatic X-ray tube) and a calibrated energy dispersive X-ray spectrometer (EDS) the accuracy of a physical model for X-ray scattering is systematically evaluated for representative samples. The knowledge of the X-ray spectrometer efficiency, but also of the spectrometer response functions makes it possible to define a physical spectral background of XRF spectra. Background subtraction relying on purely mathematical procedures is state-of-the-art. The results produced by the analytical model are at least as reliable as those obtained by Monte-Carlo simulations, even without considering the very challenging contribution of multiple scattering. Special attention has been paid to Compton broadening. Relevant applications of the implementation of the analytical model presented in this paper are the prediction of the limits of detection for particular cases or the determination of the transmission of X-ray polycapillary lenses.

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.

X-ray diagnostic installation for X-ray tomographic images

International Nuclear Information System (INIS)

Haendle, J.; Sklebitz, H.

1984-01-01

An exemplary embodiment includes at least one x-ray tube for the generation of an x-ray beam, a patient support, an image detector, and a control generator-connected with the x-ray tube and the image detector-for the purpose of moving the x-ray beam, and in opposition thereto, the image field of the image detector. There is connected to the control generator a layer height computer which calculates the enlargement from the geometric data for the tomogram. The image detector has a circuit-connected with the layer height computer-for the purpose of fading-in a marking for the dimensions in the layer plane

X-ray emission spectroscopy. X-ray fluorescence

International Nuclear Information System (INIS)

Despujols, J.

1992-01-01

Principles of X-ray emission spectrometry are first recalled, then wave-length dispersive and energy dispersive X-ray fluorescence spectrometer are described. They are essentially designed for qualitative and quantitative analysis of elements (Z>10). Sample preparation, calibration, corrections, interferences, accuracy are reviewed. Examples of use in different industries are given. (71 refs.)

Providing x-rays

International Nuclear Information System (INIS)

Mallozzi, P.J.; Epstein, H.M.

1985-01-01

This invention provides an apparatus for providing x-rays to an object that may be in an ordinary environment such as air at approximately atmospheric pressure. The apparatus comprises: means (typically a laser beam) for directing energy onto a target to produce x-rays of a selected spectrum and intensity at the target; a fluid-tight enclosure around the target; means for maintaining the pressure in the first enclosure substantially below atmospheric pressure; a fluid-tight second enclosure adjoining the first enclosure, the common wall portion having an opening large enough to permit x-rays to pass through but small enough to allow the pressure reducing means to evacuate gas from the first enclosure at least as fast as it enters through the opening; the second enclosure filled with a gas that is highly transparent to x-rays; the wall of the second enclosure to which the x-rays travel having a portion that is highly transparent to x-rays (usually a beryllium or plastic foil), so that the object to which the x-rays are to be provided may be located outside the second enclosure and adjacent thereto and thus receive the x-rays substantially unimpeded by air or other intervening matter. The apparatus is particularly suited to obtaining EXAFS (extended x-ray fine structure spectroscopy) data on a material

Simultaneous broadband observations and high-resolution X-ray spectroscopy of the transitional millisecond pulsar PSR J1023+0038

Science.gov (United States)

Coti Zelati, F.; Campana, S.; Braito, V.; Baglio, M. C.; D'Avanzo, P.; Rea, N.; Torres, D. F.

2018-03-01

We report on the first simultaneous XMM-Newton, NuSTAR, and Swift observations of the transitional millisecond pulsar PSR J1023+0038 in the X-ray active state. Our multi-wavelength campaign allowed us to investigate with unprecedented detail possible spectral variability over a broad energy range in the X-rays, as well as correlations and lags among emissions in different bands. The soft and hard X-ray emissions are significantly correlated, with no lags between the two bands. On the other hand, the X-ray emission does not correlate with the UV emission. We refine our model for the observed mode switching in terms of rapid transitions between a weak propeller regime and a rotation-powered radio pulsar state, and report on a detailed high-resolution X-ray spectroscopy using all XMM-Newton Reflection Grating Spectrometer data acquired since 2013. We discuss our results in the context of the recent discoveries on the system and of the state of the art simulations on transitional millisecond pulsars, and show how the properties of the narrow emission lines in the soft X-ray spectrum are consistent with an origin within the accretion disc.

Self-seeding scheme for the soft X-ray line at the European XFEL

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

2012-02-01

This paper discusses the potential for enhancing the capabilities of the European FEL in the soft X-ray regime. A high longitudinal coherence will be the key to such performance upgrade. In order to reach this goal we study a very compact soft X-ray self-seeding scheme originally designed at SLAC. The scheme is based on a grating monochromator, and can be straightforwardly installed in the SASE3 undulator beamline at the European XFEL. For the European XFEL fully-coherent soft X-ray pulses are particularly valuable since they naturally support the extraction of more FEL power than at saturation by exploiting tapering in the tunable-gap SASE3 undulator. Tapering consists of a stepwise change of the undulator gap from segment to segment. Based on start-to-end simulations we show that soft X-ray FEL power reaches about 800 GW, that is about an order of magnitude higher than the SASE level at saturation (100 GW). The self-seeding setup studied in this work is extremely compact (about 5 m long), and cost-effective. This last characteristic may justify to consider it as a possible addition to the European XFEL capabilities from the very beginning of the operation phase. (orig.)

Self-seeding scheme for the soft X-ray line at the European XFEL

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2012-02-15

This paper discusses the potential for enhancing the capabilities of the European FEL in the soft X-ray regime. A high longitudinal coherence will be the key to such performance upgrade. In order to reach this goal we study a very compact soft X-ray self-seeding scheme originally designed at SLAC. The scheme is based on a grating monochromator, and can be straightforwardly installed in the SASE3 undulator beamline at the European XFEL. For the European XFEL fully-coherent soft X-ray pulses are particularly valuable since they naturally support the extraction of more FEL power than at saturation by exploiting tapering in the tunable-gap SASE3 undulator. Tapering consists of a stepwise change of the undulator gap from segment to segment. Based on start-to-end simulations we show that soft X-ray FEL power reaches about 800 GW, that is about an order of magnitude higher than the SASE level at saturation (100 GW). The self-seeding setup studied in this work is extremely compact (about 5 m long), and cost-effective. This last characteristic may justify to consider it as a possible addition to the European XFEL capabilities from the very beginning of the operation phase. (orig.)

LONG-TERM X-RAY STABILITY AND ULTRAVIOLET VARIABILITY OF THE IONIZED ABSORPTION IN NGC 3783

Energy Technology Data Exchange (ETDEWEB)

Scott, A. E.; Brandt, W. N. [Department of Astronomy and Astrophysics, 525 Davey Laboratory, Pennsylvania State University, University Park, PA 16802 (United States); Behar, E.; Kaspi, S. [Department of Physics, Technion, Haifa 32000 (Israel); Crenshaw, D. M. [Department of Physics and Astronomy, Georgia State University, 25 Park Place, Suite 605, Atlanta, GA 30303 (United States); Gabel, J. R. [Physics Department, Creighton University, Omaha, NE 68178 (United States); Gibson, R. R. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Kraemer, S. B. [Institute for Astrophysics and Computational Sciences, Department of Physics, The Catholic University of America, Washington, DC 20064 (United States); Turner, T. J., E-mail: amyscott@psu.edu [Department of Physics, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States)

2014-12-20

We present the results of recent Chandra High-Energy Transmission Grating Spectrometer and Hubble Space Telescope Cosmic Origins Spectrograph observations of the nearby Seyfert 1 galaxy NGC 3783, which show a strong, nonvarying X-ray warm absorber and physically related and kinematically varying UV absorption. We compare our new observations to high-resolution, high signal-to-noise archival data from 2001, allowing a unique investigation into the long-term variations of the absorption over a 12 yr period. We find no statistically significant changes in the physical properties of the X-ray absorber, but there is a significant drop of ∼40% in the UV and X-ray flux and a significant flattening of the underlying X-ray power-law slope. Large kinematic changes are seen in the UV absorbers, possibly due to radial deceleration of the material. Similar behavior is not observed in the X-ray data, likely due to its lower-velocity resolution, which shows an outflow velocity of v {sub out} ∼ –655 km s{sup –1} in both epochs. The narrow iron Kα emission line at 6.4 keV shows no variation between epochs, and its measured width places the material producing the line at a radial distance of ∼0.03 pc from the central black hole.

X-ray detector for a panoramic X-ray unit

Energy Technology Data Exchange (ETDEWEB)

Cowell, D; Ensslin, F H

1976-01-15

The discovery deals with an X-ray detector suitable for the controlling of panoramic X-ray systems. It consists of a fluorescent image screen and a semiconductor photo cell. The output signal of the detector is proportional to the intensity of the X-radiation and the response time is large enough to follow the change of amplitude of the contours of the modulated X radiation. The detector with band-pass filter regulates, via a control system, the moving rate of the X-ray source and of the film opposite it in dependence of the intensity, so that a uniform exposure is ensured.

X-ray imaging with compound refractive lens and microfocus X-ray tube

OpenAIRE

Pina, Ladislav; Dudchik, Yury; Jelinek, Vaclav; Sveda, Libor; Marsik, Jiri; Horvath, Martin; Petr, Ondrej

2008-01-01

Compound refractive lenses (CRL), consisting of a lot number in-line concave microlenses made of low-Z material were studied. Lenses with focal length 109 mm and 41 mm for 8-keV X-rays, microfocus X-ray tube and X-ray CCD camera were used in experiments. Obtained images show intensity distribution of magnified microfocus X-ray source focal spot. Within the experiments, one lens was also used as an objective lens of the X-ray microscope, where the copper anode X-ray microfocus tube served as a...

Abdominal x-ray

Science.gov (United States)

Abdominal film; X-ray - abdomen; Flat plate; KUB x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

On the Detectability of CO Molecules in the Interstellar Medium via X-Ray Spectroscopy

Science.gov (United States)

Joachimi, Katerine; Gatuzz, Efrain; Garcia, Javier; Kallman, Timothy R.

2016-01-01

We present a study of the detectability of CO molecules in the Galactic interstellar medium using high-resolution X-ray spectra obtained with the XMM-Newton Reflection Grating Spectrometer. We analysed 10 bright low mass X-ray binaries (LMXBs) to study the CO contribution in their line of sights. A total of 25 observations were fitted with the ISMabs X-ray absorption model which includes photoabsorption cross-sections for Oi, Oii, Oiii and CO. We performed a Monte Carlo (MC) simulation analysis of the goodness of fit in order to estimate the significance of the CO detection. We determine that the statistical analysis prevents a significant detection of CO molecular X-ray absorption features, except for the lines of sight towards XTE J1718-330 and 4U 1636-53. In the case of XTE J1817-330, this is the first report of the presence of CO along its line of sight. Our results reinforce the conclusion that molecules have a minor contribution to the absorption features in the O K-edge spectral region. We estimate a CO column density lower limit to perform a significant detection with XMM-Newton of N(CO) greater than 6 x 10(exp 16) per sq cm for typical exposure times.

X-ray spectroscopy and X-ray crystallography of metalloenzymes at XFELs

International Nuclear Information System (INIS)

Yano, Junko

2016-01-01

The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting crystallography data and X-ray emission spectra, using an energy dispersive spectrometer at ambient conditions. In addition, we have developed a way to collect metal L-edge data of dilute samples using soft X-rays at XFELs. The advantages and challenges of these methods will be described in this review. (author)

Chest X-Ray

Medline Plus

Full Text Available ... talk with you about chest radiography also known as chest x-rays. Chest x-rays are the ... treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray ...

The use of diagnostic x-ray among veterinarians. Results from a survey et guidance to regulations for veterinarian's use of diagnostic x-ray

International Nuclear Information System (INIS)

Solberg, M.

2010-12-01

The use of diagnostic X-ray equipment by veterinarians in Norway is regulated by the Radiation Protection Act (Stralevernloven) as well as the Regulation for Radiation Protection and Use of Radiation (Stralevernforskriften). A revised regulation was accepted by the Norwegian government 29/10/2010; revisions relevant to veterinarians will come to force 01/01/2011. Many X-ray machines are used in veterinary clinics in Norway, and the Norwegian Radiation Protection Authority (NRPA) has therefore undertaken a study to assess their use of X-ray equipment. The main objective has been to study occupational exposure to ionizing radiation. This report summarizes data collected during a web-based survey as well as data collected from 13 inspections at veterinary clinics, including in situ measurements of scattered radiation and measurements of compliance between light field and irradiation field at a selection of veterinary clinics. The report also includes guidance to regulations that are specific for the practice of radiology in veterinary medicine. The Norwegian organization for veterinarians (Den Norske Veterinarforening) is gratefully acknowledged for distributing the web-based survey among their members and thereby enabling a large number of responses to be collected. Of 441 completed surveys, 276 (63 %) confirmed that X-ray equipment was used in their clinic. The results from the survey and inspections generally show a good approach and satisfactory daily routines with regard to the use of X-ray machines, especially concerning occupational health aspects. However, nearly 50 % of the respondents were not familiar with the regulations. During the inspection round, certain regulatory requirements were found to be less than satisfactory in most clinics. Such requirements included reporting the use of X-ray machines to the NRPA and the proper use of radiation warning symbols in rooms where X-ray equipment was situated. About 50 % of the veterinary surgeons who used X -ray

Modern X-ray spectroscopy 3. X-ray fluorescence holography

International Nuclear Information System (INIS)

Hayashi, Kouichi

2008-01-01

X-ray fluorescence holography (XFH) provides three dimensional atomic images around specified elements. The XFH uses atoms as a wave source or monitor of interference field within a crystal sample, and therefore it can record both intensity and phase of scattered X-rays. Its current performance makes it possible to apply to ultra thin film, impurity and quasicrystal. In this article, I show the theory including solutions for twin image problem, advanced measuring system, data processing for reconstruction of the atomic images and for obtaining accurate atomic positions, applications using resonant X-ray scattering and X-ray excited optical luminescence, and an example of XFH result on the local structure around copper in silicon steal. (author)

X-ray holography: X-ray interactions and their effects

International Nuclear Information System (INIS)

London, R.A.; Trebes, J.E.; Rosen, M.D.

1988-01-01

The authors summarize a theoretical study of the interactions of x-rays with a biological sample during the creation of a hologram. The choice of an optimal wavelength for x-ray holography is discussed, based on a description of scattering by objects within an aqueous environment. The problem of the motion resulting from the absorption of x-rays during a short exposure is described. The possibility of using very short exposures in order to capture the image before motion can compromise the resolution is explored. The impact of these calculation on the question of the feasibility of using an x-ray laser for holography of biological structures is discussed. 12 refs., 2 figs

Development of confocal micro X-ray fluorescence instrument using two X-ray beams

International Nuclear Information System (INIS)

Tsuji, Kouichi; Nakano, Kazuhiko; Ding Xunliang

2007-01-01

A new confocal micro X-ray fluorescence instrument was developed. This instrument has two independent micro X-ray tubes with Mo targets. A full polycapillary X-ray lens was attached to each X-ray tube. Another half polycapillary lens was attached to a silicon drift X-ray detector (SDD). The focal spots of the three lenses were adjusted to a common position. The effects of the excitation of two X-ray beams were investigated. The instrument enabled highly sensitive three-dimensional X-ray fluorescence analysis. We confirmed that the X-ray fluorescence intensity from the sample increased by applying the two independent X-ray tubes in confocal configuration. Elemental depth profiling of black wheat was demonstrated with the result that each element in the surface coat of a wheat grain showed unique distribution

Modern X-ray difraction. X-ray diffractometry for material scientists, physicists, and chemicists

International Nuclear Information System (INIS)

Spiess, L.; Schwarzer, R.; Behnken, H.; Teichert, G.

2005-01-01

The book yields a comprehensive survey over the applications of X-ray diffraction in fields like material techniques, metallurgy, electrotechniques, machine engineering, as well as micro- and nanotechniques. The necessary fundamental knowledge on X-ray diffraction are mediated foundedly and illustratively. Thereby new techniques and evaluation procedures are presented as well as well known methods. The content: Production and properties of X radiation, diffraction of X radiation, hardware for X-ray diffraction, methods of X-ray diffraction, lattice-constant determination, phase analysis, X-ray profile analysis, crystal structure analysis, X-ray radiographic stress analysis, X-ray radiographic texture analysis, crystal orientation determination, pecularities at thin films, small angle scattering

X-Ray Exam: Pelvis

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Pelvis KidsHealth / For Parents / X-Ray Exam: ... Ray Exam: Hip Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

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...

X-ray examination apparatus

NARCIS (Netherlands)

2000-01-01

The invention relates to an X-ray apparatus which includes an adjustable X-ray filter. In order to adjust an intensity profile of the X-ray beam, an X-ray absorbing liquid is transported to filter elements of the X-ray filter. Such transport is susceptible to gravitational forces which lead to an

Development of x-ray laminography under an x-ray microscopic condition

International Nuclear Information System (INIS)

Hoshino, Masato; Uesugi, Kentaro; Takeuchi, Akihisa; Suzuki, Yoshio; Yagi, Naoto

2011-01-01

An x-ray laminography system under an x-ray microscopic condition was developed to obtain a three-dimensional structure of laterally-extended planar objects which were difficult to observe by x-ray tomography. An x-ray laminography technique was introduced to an x-ray transmission microscope with zone plate optics. Three prototype sample holders were evaluated for x-ray imaging laminography. Layered copper grid sheets were imaged as a laminated sample. Diatomite powder on a silicon nitride membrane was measured to confirm the applicability of this method to non-planar micro-specimens placed on the membrane. The three-dimensional information of diatom shells on the membrane was obtained at a spatial resolution of sub-micron. Images of biological cells on the membrane were also obtained by using a Zernike phase contrast technique.

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, ... you about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed ...

Six dimensional X-ray Tensor Tomography with a compact laboratory setup

Science.gov (United States)

Sharma, Y.; Wieczorek, M.; Schaff, F.; Seyyedi, S.; Prade, F.; Pfeiffer, F.; Lasser, T.

2016-09-01

Attenuation based X-ray micro computed tomography (XCT) provides three-dimensional images with micrometer resolution. However, there is a trade-off between the smallest size of the structures that can be resolved and the measurable sample size. In this letter, we present an imaging method using a compact laboratory setup that reveals information about micrometer-sized structures within samples that are several orders of magnitudes larger. We combine the anisotropic dark-field signal obtained in a grating interferometer and advanced tomographic reconstruction methods to reconstruct a six dimensional scattering tensor at every spatial location in three dimensions. The scattering tensor, thus obtained, encodes information about the orientation of micron-sized structures such as fibres in composite materials or dentinal tubules in human teeth. The sparse acquisition schemes presented in this letter enable the measurement of the full scattering tensor at every spatial location and can be easily incorporated in a practical, commercially feasible laboratory setup using conventional X-ray tubes, thus allowing for widespread industrial applications.

Microfocussing of synchrotron X-rays using X-ray refractive lens

Indian Academy of Sciences (India)

X-ray lenses are fabricated in polymethyl methacrylate using deep X-ray lithography beamline of Indus-2. The focussing performance of these lenses is evaluated using Indus-2 and Diamond Light Source Ltd. The process steps for the fabrication of X-ray lenses and microfocussing at 10 keV at moderate and low emittance ...

Grating-based phase contrast tomosynthesis imaging: Proof-of-concept experimental studies

International Nuclear Information System (INIS)

Li, Ke; Ge, Yongshuai; Garrett, John; Bevins, Nicholas; Zambelli, Joseph; Chen, Guang-Hong

2014-01-01

Purpose: This paper concerns the feasibility of x-ray differential phase contrast (DPC) tomosynthesis imaging using a grating-based DPC benchtop experimental system, which is equipped with a commercial digital flat-panel detector and a medical-grade rotating-anode x-ray tube. An extensive system characterization was performed to quantify its imaging performance. Methods: The major components of the benchtop system include a diagnostic x-ray tube with a 1.0 mm nominal focal spot size, a flat-panel detector with 96 μm pixel pitch, a sample stage that rotates within a limited angular span of ±30°, and a Talbot-Lau interferometer with three x-ray gratings. A total of 21 projection views acquired with 3° increments were used to reconstruct three sets of tomosynthetic image volumes, including the conventional absorption contrast tomosynthesis image volume (AC-tomo) reconstructed using the filtered-backprojection (FBP) algorithm with the ramp kernel, the phase contrast tomosynthesis image volume (PC-tomo) reconstructed using FBP with a Hilbert kernel, and the differential phase contrast tomosynthesis image volume (DPC-tomo) reconstructed using the shift-and-add algorithm. Three inhouse physical phantoms containing tissue-surrogate materials were used to characterize the signal linearity, the signal difference-to-noise ratio (SDNR), the three-dimensional noise power spectrum (3D NPS), and the through-plane artifact spread function (ASF). Results: While DPC-tomo highlights edges and interfaces in the image object, PC-tomo removes the differential nature of the DPC projection data and its pixel values are linearly related to the decrement of the real part of the x-ray refractive index. The SDNR values of polyoxymethylene in water and polystyrene in oil are 1.5 and 1.0, respectively, in AC-tomo, and the values were improved to 3.0 and 2.0, respectively, in PC-tomo. PC-tomo and AC-tomo demonstrate equivalent ASF, but their noise characteristics quantified by the 3D NPS

Grating-based phase contrast tomosynthesis imaging: Proof-of-concept experimental studies

Science.gov (United States)

Li, Ke; Ge, Yongshuai; Garrett, John; Bevins, Nicholas; Zambelli, Joseph; Chen, Guang-Hong

2014-01-01

Purpose: This paper concerns the feasibility of x-ray differential phase contrast (DPC) tomosynthesis imaging using a grating-based DPC benchtop experimental system, which is equipped with a commercial digital flat-panel detector and a medical-grade rotating-anode x-ray tube. An extensive system characterization was performed to quantify its imaging performance. Methods: The major components of the benchtop system include a diagnostic x-ray tube with a 1.0 mm nominal focal spot size, a flat-panel detector with 96 μm pixel pitch, a sample stage that rotates within a limited angular span of ±30°, and a Talbot-Lau interferometer with three x-ray gratings. A total of 21 projection views acquired with 3° increments were used to reconstruct three sets of tomosynthetic image volumes, including the conventional absorption contrast tomosynthesis image volume (AC-tomo) reconstructed using the filtered-backprojection (FBP) algorithm with the ramp kernel, the phase contrast tomosynthesis image volume (PC-tomo) reconstructed using FBP with a Hilbert kernel, and the differential phase contrast tomosynthesis image volume (DPC-tomo) reconstructed using the shift-and-add algorithm. Three inhouse physical phantoms containing tissue-surrogate materials were used to characterize the signal linearity, the signal difference-to-noise ratio (SDNR), the three-dimensional noise power spectrum (3D NPS), and the through-plane artifact spread function (ASF). Results: While DPC-tomo highlights edges and interfaces in the image object, PC-tomo removes the differential nature of the DPC projection data and its pixel values are linearly related to the decrement of the real part of the x-ray refractive index. The SDNR values of polyoxymethylene in water and polystyrene in oil are 1.5 and 1.0, respectively, in AC-tomo, and the values were improved to 3.0 and 2.0, respectively, in PC-tomo. PC-tomo and AC-tomo demonstrate equivalent ASF, but their noise characteristics quantified by the 3D NPS

A TEST OF THE NATURE OF THE FE K LINE IN THE NEUTRON STAR LOW-MASS X-RAY BINARY SERPENS X-1

Energy Technology Data Exchange (ETDEWEB)

Chiang, Chia-Ying; Cackett, Edward M. [Department of Physics and Astronomy, Wayne State University, 666 W. Hancock, Detroit, MI 48202 (United States); Miller, Jon M. [Department of Astronomy, The University of Michigan, 500 Church Street, Ann Arbor, MI48109-1046 (United States); Barret, Didier [Universite de Toulouse, UPS-OMP, Toulouse (France); Fabian, Andy C.; Parker, Michael L. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); D’Aì, Antonino [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Bhattacharyya, Sudip [Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, Mumbai 400005 (India); Burderi, Luciano [Dipartimento di Fisica, Università degli Studi di Cagliari, SP Monserrato-Sestu, KM 0.7, I-09042 Monserrato (Italy); Salvo, Tiziana Di; Iaria, Rosario [Dipartimento di Fisica e Chimica, Universitá di Palermo, via Archirafi 36, I-90123 Palermo (Italy); Egron, Elise [INAF-Osservatorio Astronomico di Cagliari, via della Scienza 5, I-09047 Selargius (Italy); Homan, Jeroen [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue 37-582D, Cambridge, MA 02139 (United States); Lin, Dacheng [Space Science Center, University of New Hampshire, Durham, NH 03824 (United States); Miller, M. Coleman, E-mail: ft8320@wayne.edu [Department of Astronomy and Joint Space-Science Institute, University of Maryland, College Park, MD 20742-2421 (United States)

2016-04-20

Broad Fe K emission lines have been widely observed in the X-ray spectra of black hole systems as well as in neutron star systems. The intrinsically narrow Fe K fluorescent line is generally believed to be part of the reflection spectrum originating in an illuminated accretion disk which is broadened by strong relativistic effects. However, the nature of the lines in neutron star low-mass X-ray binaries (LMXBs) has been a matter of debate. We therefore obtained the longest, high-resolution X-ray spectrum of a neutron star LMXB to date with a 300 ks Chandra High Energy Transmission Grating Spectrometer (HETGS) observation of Serpens X-1. The observation was taken under the “continuous clocking” mode, and thus was free of photon pile-up effects. We carry out a systematic analysis and find that the blurred reflection model fits the Fe line of Serpens X-1 significantly better than a broad Gaussian component does, implying that the relativistic reflection scenario is much preferred. Chandra HETGS also provides a highest spectral resolution view of the Fe K region and we find no strong evidence for additional narrow lines.

High-Resolution X-Ray Spectra of the Symbiotic Star SS73 17

Science.gov (United States)

Eze, R. N. C.; Luna, G. J. M.; Smith, R. K.

2010-01-01

SS73 17 was an innocuous Mira-type symbiotic star until the International Gamma-Ray Astrophysics Laboratory and Swift discovered its bright hard X-ray emission, adding it to the small class of "hard X-ray emitting symbiotics." Suzaku observations in 2006 then showed it emits three bright iron lines as well, with little to no emission in the 0.3-2.0 keV bandpass. We present here follow-up observations with the Chandra High Energy Transmission Grating and Suzaku that confirm the earlier detection of strong emission lines of Fe K(alpha) fluorescence, Fe XXV and Fe XXVI but also show significantly more soft X-ray emission. The high-resolution spectrum also shows emission lines of other highly ionized ions as Si xiv and possibly S XVI. In addition, a re-analysis of the 2006 Suzaku data using the latest calibration shows that the hard (15-50 keV) X-ray emission is brighter than previously thought and remains constant in both the 2006 and 2008 data. The G ratio calculated from the Fe xxv lines shows that these lines are thermal, not photoionized, in origin.With the exception of the hard X-ray emission, the spectra from both epochs can be fit using thermal radiation assuming a differential emission measure based on a cooling-flow model combined with a full and partial absorber. We show that acceptable fits can be obtained for all the data in the 1-10 keV band varying only the partial absorber. Based on the temperature and accretion rate, the thermal emission appears to be arising from the boundary layer between the accreting white dwarf and the accretion disk.

HIGH-RESOLUTION X-RAY SPECTRA OF THE SYMBIOTIC STAR SS73 17

International Nuclear Information System (INIS)

Eze, R. N. C.; Luna, G. J. M.; Smith, R. K.

2010-01-01

SS73 17 was an innocuous Mira-type symbiotic star until the International Gamma-Ray Astrophysics Laboratory and Swift discovered its bright hard X-ray emission, adding it to the small class of 'hard X-ray emitting symbiotics'. Suzaku observations in 2006 then showed it emits three bright iron lines as well, with little to no emission in the 0.3-2.0 keV bandpass. We present here follow-up observations with the Chandra High Energy Transmission Grating and Suzaku that confirm the earlier detection of strong emission lines of Fe Kα fluorescence, Fe XXV and Fe XXVI but also show significantly more soft X-ray emission. The high-resolution spectrum also shows emission lines of other highly ionized ions as Si XIV and possibly S XVI. In addition, a re-analysis of the 2006 Suzaku data using the latest calibration shows that the hard (15-50 keV) X-ray emission is brighter than previously thought and remains constant in both the 2006 and 2008 data. The G ratio calculated from the Fe XXV lines shows that these lines are thermal, not photoionized, in origin. With the exception of the hard X-ray emission, the spectra from both epochs can be fit using thermal radiation assuming a differential emission measure based on a cooling-flow model combined with a full and partial absorber. We show that acceptable fits can be obtained for all the data in the 1-10 keV band varying only the partial absorber. Based on the temperature and accretion rate, the thermal emission appears to be arising from the boundary layer between the accreting white dwarf and the accretion disk.

X-ray detector array

International Nuclear Information System (INIS)

Houston, J.M.

1980-01-01

The object of the invention (an ionization chamber X-ray detector array for use with high speed computerised tomographic imaging apparatus) is to reduce the time required to produce a tomographic image. The detector array described determines the distribution of X-ray intensities in one or more flat, coplanar X-ray beams. It comprises three flat anode sheets parallel to the X-ray beam, a plurality of rod-like cathodes between the anodes, a detector gas between the electrodes and a means for applying a potential between the electrodes. Each of the X-ray sources is collimated to give a narrow, planar section of X-ray photons. Sets of X-ray sources in the array are pulsed simultaneously to obtain X-ray transmission data for tomographic image reconstruction. (U.K.)

Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

Directory of Open Access Journals (Sweden)

L. Miaja-Avila

2015-03-01

Full Text Available We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

X-ray instrumentation in astronomy

International Nuclear Information System (INIS)

Cuhlane, J.L.

1985-01-01

This book presents the proceedings of a conference devoted to x-ray instrumentation in astronomy. Special sections are: AXAF X-Ray Optical Systems; Specialized X-Ray Systems; X-Ray Optical Systems I; X-Ray Optical Systems II; Gas Filled X-Ray Detectors II; The NASA Advanced X-Ray Astrophysics Facility; X-Ray and EUV Spectrometers; Microchannel Plates; and Solid State Detectors

Monte Carlo simulation of grating-based neutron phase contrast imaging at CPHS

International Nuclear Information System (INIS)

Zhang Ran; Chen Zhiqiang; Huang Zhifeng; Xiao Yongshun; Wang Xuewu; Wie Jie; Loong, C.-K.

2011-01-01

Since the launching of the Compact Pulsed Hadron Source (CPHS) project of Tsinghua University in 2009, works have begun on the design and engineering of an imaging/radiography instrument for the neutron source provided by CPHS. The instrument will perform basic tasks such as transmission imaging and computerized tomography. Additionally, we include in the design the utilization of coded-aperture and grating-based phase contrast methodology, as well as the options of prompt gamma-ray analysis and neutron-energy selective imaging. Previously, we had implemented the hardware and data-analysis software for grating-based X-ray phase contrast imaging. Here, we investigate Geant4-based Monte Carlo simulations of neutron refraction phenomena and then model the grating-based neutron phase contrast imaging system according to the classic-optics-based method. The simulated experimental results of the retrieving phase shift gradient information by five-step phase-stepping approach indicate the feasibility of grating-based neutron phase contrast imaging as an option for the cold neutron imaging instrument at the CPHS.

Panoramic Dental X-Ray

Science.gov (United States)

... Physician Resources Professions Site Index A-Z Panoramic Dental X-ray Panoramic dental x-ray uses a very small dose of ... x-ray , is a two-dimensional (2-D) dental x-ray examination that captures the entire mouth ...

Chest X-Ray

Medline Plus

Full Text Available ... I’d like to talk with you about chest radiography also known as chest x-rays. Chest x-rays are the most ... far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot org. Thank you for your time! ...

Miniature x-ray point source for alignment and calibration of x-ray optics

International Nuclear Information System (INIS)

Price, R.H.; Boyle, M.J.; Glaros, S.S.

1977-01-01

A miniature x-ray point source of high brightness similar to that of Rovinsky, et al. is described. One version of the x-ray source is used to align the x-ray optics on the Argus and Shiva laser systems. A second version is used to determine the spatial and spectral transmission functions of the x-ray optics. The spatial and spectral characteristics of the x-ray emission from the x-ray point source are described. The physical constraints including size, intensity and thermal limitations, and useful lifetime are discussed. The alignment and calibration techniques for various x-ray optics and detector combinations are described

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

X-Ray Exam: Forearm

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Forearm KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

X-Ray Exam: Foot

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Foot KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

X-Ray Exam: Wrist

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Wrist KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Thoracic spine x-ray

Science.gov (United States)

Vertebral radiography; X-ray - spine; Thoracic x-ray; Spine x-ray; Thoracic spine films; Back films ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

X-Ray Exam: Finger

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Finger KidsHealth / For Parents / X-Ray Exam: ... Muscles, and Joints Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Diffraction Efficiency Testing of Sinusoidal and Blazed Off-Plane Reflection Gratings

Science.gov (United States)

Tutt, James H.; McEntaffer, Randall L.; Marlowe, Hannah; Miles, Drew M.; Peterson, Thomas J.; Deroo, Casey T.; Scholze, Frank; Laubis, Christian

2016-09-01

Reflection gratings in the off-plane mount have the potential to enhance the performance of future high resolution soft X-ray spectrometers. Diffraction efficiency can be optimized through the use of blazed grating facets, achieving high-throughput on one side of zero-order. This paper presents the results from a comparison between a grating with a sinusoidally grooved profile and two gratings that have been blazed. The results show that the blaze does increase throughput to one side of zero-order; however, the total throughput of the sinusoidal gratings is greater than the blazed gratings, suggesting the method of manufacturing the blazed gratings does not produce precise facets. The blazed gratings were also tested in their Littrow and anti-Littrow configurations to quantify diffraction efficiency sensitivity to rotations about the grating normal. Only a small difference in the energy at which efficiency is maximized between the Littrow and anti-Littrow configurations is seen with a small shift in peak efficiency towards higher energies in the anti-Littrow case. This is due to a decrease in the effective blaze angle in the anti-Littrow mounting. This is supported by PCGrate-SX V6.1 modeling carried out for each blazed grating which predicts similar response trends in the Littrow and anti-Littrow orientations.

Soft x-ray lasers

International Nuclear Information System (INIS)

Matthews, D.L.; Rosen, M.D.

1988-01-01

One of the elusive dreams of laser physicists has been the development of an x-ray laser. After 25 years of waiting, the x-ray laser has at last entered the scientific scene, although those now in operation are still laboratory prototypes. They produce soft x rays down to about five nanometers. X-ray lasers retain the usual characteristics of their optical counterparts: a very tight beam, spatial and temporal coherence, and extreme brightness. Present x-ray lasers are nearly 100 times brighter that the next most powerful x-ray source in the world: the electron synchrotron. Although Lawrence Livermore National Laboratory (LLNL) is widely known for its hard-x-ray laser program which has potential applications in the Strategic Defense Initiative, the soft x-ray lasers have no direct military applications. These lasers, and the scientific tools that result from their development, may one day have a place in the design and diagnosis of both laser fusion and hard x-ray lasers. The soft x-ray lasers now in operation at the LLNL have shown great promise but are still in the primitive state. Once x-ray lasers become reliable, efficient, and economical, they will have several important applications. Chief among them might be the creation of holograms of microscopic biological structures too small to be investigated with visible light. 5 figs

Nano-metrology: The art of measuring X-ray mirrors with slope errors <100 nrad

Energy Technology Data Exchange (ETDEWEB)

Alcock, Simon G., E-mail: simon.alcock@diamond.ac.uk; Nistea, Ioana; Sawhney, Kawal [Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom)

2016-05-15

We present a comprehensive investigation of the systematic and random errors of the nano-metrology instruments used to characterize synchrotron X-ray optics at Diamond Light Source. With experimental skill and careful analysis, we show that these instruments used in combination are capable of measuring state-of-the-art X-ray mirrors. Examples are provided of how Diamond metrology data have helped to achieve slope errors of <100 nrad for optical systems installed on synchrotron beamlines, including: iterative correction of substrates using ion beam figuring and optimal clamping of monochromator grating blanks in their holders. Simulations demonstrate how random noise from the Diamond-NOM’s autocollimator adds into the overall measured value of the mirror’s slope error, and thus predict how many averaged scans are required to accurately characterize different grades of mirror.

Nano-metrology: The art of measuring X-ray mirrors with slope errors <100 nrad

International Nuclear Information System (INIS)

Alcock, Simon G.; Nistea, Ioana; Sawhney, Kawal

2016-01-01

We present a comprehensive investigation of the systematic and random errors of the nano-metrology instruments used to characterize synchrotron X-ray optics at Diamond Light Source. With experimental skill and careful analysis, we show that these instruments used in combination are capable of measuring state-of-the-art X-ray mirrors. Examples are provided of how Diamond metrology data have helped to achieve slope errors of <100 nrad for optical systems installed on synchrotron beamlines, including: iterative correction of substrates using ion beam figuring and optimal clamping of monochromator grating blanks in their holders. Simulations demonstrate how random noise from the Diamond-NOM’s autocollimator adds into the overall measured value of the mirror’s slope error, and thus predict how many averaged scans are required to accurately characterize different grades of mirror.

Nano-metrology: The art of measuring X-ray mirrors with slope errors <100 nrad.

Science.gov (United States)

Alcock, Simon G; Nistea, Ioana; Sawhney, Kawal

2016-05-01

We present a comprehensive investigation of the systematic and random errors of the nano-metrology instruments used to characterize synchrotron X-ray optics at Diamond Light Source. With experimental skill and careful analysis, we show that these instruments used in combination are capable of measuring state-of-the-art X-ray mirrors. Examples are provided of how Diamond metrology data have helped to achieve slope errors of <100 nrad for optical systems installed on synchrotron beamlines, including: iterative correction of substrates using ion beam figuring and optimal clamping of monochromator grating blanks in their holders. Simulations demonstrate how random noise from the Diamond-NOM's autocollimator adds into the overall measured value of the mirror's slope error, and thus predict how many averaged scans are required to accurately characterize different grades of mirror.

Soft x-ray emission from postpulse expanding laser-produced plasmas

International Nuclear Information System (INIS)

Weaver, J.L.; Feldman, U.; Mostovych, A.N.; Seely, J.F.; Colombant, D.; Holland, G.

2003-01-01

A diagnostic spectrometer has been developed at the Naval Research Laboratory to measure the time resolved absolute intensity of radiation emitted from targets irradiated by the Nike laser. The spectrometer consists of a dispersive transmission grating of 2500 lines/mm or 5000 lines/mm and a detection system consisting of an absolutely calibrated Si photodiode array and a charge coupled device camera. In this article, this spectrometer was used to study the spatial distribution of soft x-ray radiation from low Z elements (primarily carbon) that lasted tens of nanoseconds after the main laser illumination was over. We recorded soft x-ray emission as a function of the target material and target orientation with respect to the incoming laser beam and the spectrometer line of sight. While a number of spectral features have been identified in the data, the instrument's combined temporal and spatial resolution allowed observation of the plasma expansion from CH targets for up to ∼25 ns after the cessation of the main laser pulse. The inferred plasma expansion velocities are slightly higher than those previously reported

Soft x-ray emission from postpulse expanding laser-produced plasmas

Science.gov (United States)

Weaver, J. L.; Feldman, U.; Mostovych, A. N.; Seely, J. F.; Colombant, D.; Holland, G.

2003-12-01

A diagnostic spectrometer has been developed at the Naval Research Laboratory to measure the time resolved absolute intensity of radiation emitted from targets irradiated by the Nike laser. The spectrometer consists of a dispersive transmission grating of 2500 lines/mm or 5000 lines/mm and a detection system consisting of an absolutely calibrated Si photodiode array and a charge coupled device camera. In this article, this spectrometer was used to study the spatial distribution of soft x-ray radiation from low Z elements (primarily carbon) that lasted tens of nanoseconds after the main laser illumination was over. We recorded soft x-ray emission as a function of the target material and target orientation with respect to the incoming laser beam and the spectrometer line of sight. While a number of spectral features have been identified in the data, the instrument's combined temporal and spatial resolution allowed observation of the plasma expansion from CH targets for up to ˜25 ns after the cessation of the main laser pulse. The inferred plasma expansion velocities are slightly higher than those previously reported.

A full-field transmission x-ray microscope for time-resolved imaging of magnetic nanostructures

Energy Technology Data Exchange (ETDEWEB)

Ewald, J.; Nisius, T.; Abbati, G.; Baumbach, S.; Overbuschmann, J.; Wilhein, T. [Institute for X-Optics (IXO), Hochschule Koblenz, Joseph-Rovan-Allee 2, 53424 Remagen (Germany); Wessels, P.; Wieland, M.; Drescher, M. [The Hamburg Centre for Ultrafast Imaging (CUI), University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Institut für Experimentalphysik, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Vogel, A. [Institut für Angewandte Physik, University of Hamburg, Jungiusstraße 11, 20355 Hamburg (Germany); Viefhaus, J. [Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, 22607 Hamburg (Germany); Meier, G. [The Hamburg Centre for Ultrafast Imaging (CUI), University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg (Germany)

2016-01-28

Sub-nanosecond magnetization dynamics of small permalloy (Ni{sub 80}Fe{sub 20}) elements has been investigated with a new full-field transmission microscope at the soft X-ray beamline P04 of the high brilliance synchrotron radiation source PETRA III. The soft X-ray microscope generates a flat-top illumination field of 20 μm diameter using a grating condenser. A tilted nanostructured magnetic sample can be excited by a picosecond electric current pulse via a coplanar waveguide. The transmitted light of the sample plane is directly imaged by a micro zone plate with < 65 nm resolution onto a 2D gateable X-ray detector to select one particular bunch in the storage ring that probes the time evolution of the dynamic information successively via XMCD spectromicroscopy in a pump-probe scheme. In the experiments it was possible to generate a homogeneously magnetized state in patterned magnetic layers by a strong magnetic Oersted field pulse of 200 ps duration and directly observe the recovery to the initial flux-closure vortex patterns.

Frequency filter of seed x-ray by use of x-ray laser medium. Toward the generation of the temporally coherent x-ray laser

International Nuclear Information System (INIS)

Hasegawa, Noboru; Kawachi, Tetsuya; Kishimoto, Maki; Sukegawa, Kouta; Tanaka, Momoko; Ochi, Yoshihiro; Nishikino, Masaharu; Nagashima, Keisuke; Kato, Yoshiaki; Renzhong, Tai

2009-01-01

We evaluate the characteristics of a higher-order harmonics light as a seed X-ray amplified through a laser-produced X-ray amplifier. The narrow spectral bandwidth of the X-ray amplifier works as the frequency filter of the seed X-ray, resulting in that only the temporally coherent X-ray is amplified. Experimental investigation using the 29th-order harmonic light of the Ti:sapphire laser at a wavelength of 26.9 nm together with a neon-like manganese X-ray laser medium shows evident spectral narrowing of the seed X-ray and amplification without serious diffraction effects on the propagation of the amplified X-ray beam. This implies that the present combination is potential to realize temporally coherent X-ray lasers, with an expected duration of approximately 400 fs. (author)

Joint European x-ray monitor (JEM-X): x-ray monitor for ESA's

DEFF Research Database (Denmark)

Schnopper, H.W.; Budtz-Joergensen, C.; Westergaard, Niels Jørgen Stenfeldt

1996-01-01

JEM-X will extend the energy range of the gamma ray instruments on ESA's INTEGRAL mission (SPI, IBIS) to include the x-ray band. JEM-X will provide images with arcminute angular resolution in the 2 - 60 keV band. The baseline photon detection system consists of two identical, high pressure, imagi...

Wide field x-ray telescopes: Detecting x-ray transients/afterglows related to GRBs

International Nuclear Information System (INIS)

Hudec, Rene; Pina, Ladislav; Inneman, Adolf; Gorenstein, Paul

1998-01-01

The recent discovery of X-ray afterglows of GRBs opens the possibility of analyses of GRBs by their X-ray detections. However, imaging X-ray telescopes in current use mostly have limited fields of view. Alternative X-ray optics geometries achieving very large fields of view have been theoretically suggested in the 70's but not constructed and used so far. We review the geometries and basic properties of the wide-field X-ray optical systems based on one- and two-dimensional lobster-eye geometry and suggest technologies for their development and construction. First results of the development of double replicated X-ray reflecting flats for use in one-dimensional X-ray optics of lobster-eye type are presented and discussed. The optimum strategy for locating GRBs upon their X-ray counterparts is also presented and discussed

Status of Mirror Development for the Marshall Grazing Incidence X-ray Spectrometer (MaGIXS)

Science.gov (United States)

Champey, P. R.; Winebarger, A. R.; Kobayashi, K.; Savage, S. L.; Ramsey, B.; Kolodziejczak, J.; Speegle, C.; Young, M.; Kester, T.; Cheimets, P.; Hertz, E.

2017-12-01

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a NASA sounding rocket instrument designed to observe soft X-ray emissions at 0.5 - 2.0 keV energies (24 - 6 Å) from a solar active region. MaGIXS will, for the first time, obtain spatially resolved spectra of high-temperature, low-emission plasma within an active region core. The unique optical design includes a Wolter I telescope and a 3-optic grazing incidence spectrograph. The spectrograph consists of a finite conjugate, stigmatic mirror pair and a planar varied line space grating. The grazing incidence mirrors are being developed at NASA Marshall Space Flight Center (MSFC) and are produced using electroform nickel-replication techniques, employing the same facilities developed for HERO, FOXSI, ART-XC and IXPE. The MaGIXS mirror mandrels have been fabricated, figured, and have completed the first phase of polishing. A set of three test shells were replicated and exposed to X-rays in the Stray Light Facility (SLF) at MSFC. Here we present results from mandrel metrology and X-ray testing at the SLF. We also discuss the development of a new polishing technique for the MaGIXS mirror mandrels, where we plan to use the Zeeko polishing machine.

X rays and condensed matter

International Nuclear Information System (INIS)

Daillant, J.

1997-01-01

After a historical review of the discovery and study of X rays, the various interaction processes between X rays and matter are described: Thomson scattering, Compton scattering, X-photon absorption through photoelectric effect, and magnetic scattering. X ray sources such as the European Synchrotron Radiation Facility (ESRF) are described. The various X-ray applications are presented: imagery such as X tomography, X microscopy, phase contrast; X-ray photoelectron spectroscopy and X-ray absorption spectroscopy; X-ray scattering and diffraction techniques

Extending the methodology of X-ray crystallography to allow X-ray microscopy without X-ray optics

International Nuclear Information System (INIS)

Miao Jianwei; Kirz, Janos; Sayre, David; Charalambous, Pambos

2000-01-01

We demonstrate that the soft X-ray diffraction pattern from a micron-size noncrystalline specimen can be recorded and inverted to form a high-resolution image. The phase problem is overcome by oversampling the diffraction pattern. The image is obtained using an iterative algorithm. The technique provides a method for X-ray microscopy requiring no high-resolution X-ray optical elements or detectors. In the present work, a resolution of approximately 60 nm was obtained, but we believe that considerably higher resolution can be achieved

Dental X-ray apparatus

International Nuclear Information System (INIS)

Weiss, M.E.

1980-01-01

Intra-oral dental X-ray apparatus for panoramic radiography is described in detail. It comprises a tubular target carrier supporting at its distal end a target with an inclined forward face. Image definition is improved by positioning in the path of the X-rays a window of X-ray transmitting ceramic material, e.g. 90% oxide of Be, or Al, 7% Si0 2 . The target carrier forms a probe which can be positioned in the patient's mouth. X-rays are directed forwardly and laterally of the target to an X-ray film positioned externally. The probe is provided with a detachable sleeve having V-form arms of X-ray opaque material which serve to depress the tongue out of the radiation path and also shield the roof of the mouth and other regions of the head from the X-ray pattern. A cylindrical lead shield defines the X-ray beam angle. (author)

X-ray diagnostics for TFTR

International Nuclear Information System (INIS)

von Goeler, S.; Hill, K.W.; Bitter, M.

1982-12-01

A short description of the x-ray diagnostic preparation for the TFTR tokamak is given. The x-ray equipment consists of the limiter x-ray monitoring system, the soft x-ray pulse-height-analysis-system, the soft x-ray imaging system and the x-ray crystal spectrometer. Particular attention is given to the radiation protection of the x-ray systems from the neutron environment

X-ray beam generator

International Nuclear Information System (INIS)

Koller, T.J.; Randmer, J.A.

1977-01-01

A method of minimizing the preferential angular absorption of the divergent beam from an X-ray generator is described. The generator consists of an X-ray shielded housing with an X-ray transmissive window symmetrically placed in radial alignment with a focal spot area on a sloped target surface of an X-ray tube in the housing. The X-ray tube may be of the stationary anode type or of the rotating anode type. (U.K.)

An algebraic iterative reconstruction technique for differential X-ray phase-contrast computed tomography.

Science.gov (United States)

Fu, Jian; Schleede, Simone; Tan, Renbo; Chen, Liyuan; Bech, Martin; Achterhold, Klaus; Gifford, Martin; Loewen, Rod; Ruth, Ronald; Pfeiffer, Franz

2013-09-01

Iterative reconstruction has a wide spectrum of proven advantages in the field of conventional X-ray absorption-based computed tomography (CT). In this paper, we report on an algebraic iterative reconstruction technique for grating-based differential phase-contrast CT (DPC-CT). Due to the differential nature of DPC-CT projections, a differential operator and a smoothing operator are added to the iterative reconstruction, compared to the one commonly used for absorption-based CT data. This work comprises a numerical study of the algorithm and its experimental verification using a dataset measured at a two-grating interferometer setup. Since the algorithm is easy to implement and allows for the extension to various regularization possibilities, we expect a significant impact of the method for improving future medical and industrial DPC-CT applications. Copyright © 2012. Published by Elsevier GmbH.

The O VI Mystery: Mismatch between X-Ray and UV Column Densities

Science.gov (United States)

Mathur, S.; Nicastro, F.; Gupta, A.; Krongold, Y.; McLaughlin, B. M.; Brickhouse, N.; Pradhan, A.

2017-12-01

The UV spectra of Galactic and extragalactic sightlines often show O VI absorption lines at a range of redshifts, and from a variety of sources from the Galactic circumgalactic medium to active galactic nuclei (AGN) outflows. Inner shell O VI absorption is also observed in X-ray spectra (at λ =22.03 Å), but the column density inferred from the X-ray line was consistently larger than that from the UV line. Here we present a solution to this discrepancy for the z = 0 systems. The O II Kβ line {}4{S}0\\to {(}3D)3{p}4P at 562.40 eV (≡22.04 Å) is blended with the O VI Kα line in X-ray spectra. We estimate the strength of this O II line in two different ways, and show that in most cases the O II line accounts for the entire blended line. The small amount of O VI equivalent width present in some cases has column density entirely consistent with the UV value. This solution to the O VI discrepancy, however, does not apply to high column-density systems like AGN outflows. We discuss other possible causes to explain their UV/X-ray mismatch. The O VI and O II lines will be resolved by gratings on board the proposed mission Arcus and the concept mission Lynx, and would allow the detection of weak O VI lines not just at z = 0, but also at higher redshift.

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 ...

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...

X-ray apparatus

International Nuclear Information System (INIS)

Grady, J.K.

1985-01-01

X-ray apparatus is described which has a shutter between the X-ray source and the patient. The shutter controls the level of radiation to which the patient is exposed instead of merely discontinuing the electric power supplied to the source. When the shutter is opened a radiation sensor senses the level of X-radiation. When a preset quantity of X-radiation has been measured an exposure control closes the shutter. Instead of using the radiation sensor, the integrated power supplied to the anode of the X-ray source may be measured. (author)

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.

Measurement of picometre non-linearity in an optical grating encoder using x-ray interferometry

Science.gov (United States)

Yacoot, Andrew; Cross, Nigel

2003-01-01

X-ray interferometry has been used to characterize the non-linearity in an optical encoder displacement measuring system. Traceable measurements of the non-linearity have been made and an estimation of the uncertainty associated with the measurements is given. Cyclic errors with a magnitude of up to 50 pm and periodicity of the encoder system (128 nm) have been recorded.

CCD-based X-ray detectors for X-ray diffraction studies

International Nuclear Information System (INIS)

Ito, K.; Amemiya, Y.

1999-01-01

CCD-based X-ray detectors are getting to be used for X-ray diffraction studies especially in the studies where real time (automated) measurements and time-resolved measurements are required. Principles and designs of two typical types of CCD-based detectors are described; one is ths system in which x-ray image intensifiers are coupled to maximize the detective quantum efficiency for time-resolved measurements, and the other is the system in which tapered optical fibers are coupled for the reduction of the image into the CCD, which is optimized for automated measurements for protein crystallography. These CCD-based X-ray detectors have an image distortion and non-uniformity of response to be corrected by software. Correction schemes which we have developed are also described. (author)

Gratings for synchrotron and FEL beamlines: a project for the manufacture of ultra-precise gratings at Helmholtz Zentrum Berlin.

Science.gov (United States)

Siewert, F; Löchel, B; Buchheim, J; Eggenstein, F; Firsov, A; Gwalt, G; Kutz, O; Lemke, St; Nelles, B; Rudolph, I; Schäfers, F; Seliger, T; Senf, F; Sokolov, A; Waberski, Ch; Wolf, J; Zeschke, T; Zizak, I; Follath, R; Arnold, T; Frost, F; Pietag, F; Erko, A

2018-01-01

Blazed gratings are of dedicated interest for the monochromatization of synchrotron radiation when a high photon flux is required, such as, for example, in resonant inelastic X-ray scattering experiments or when the use of laminar gratings is excluded due to too high flux densities and expected damage, for example at free-electron laser beamlines. Their availability became a bottleneck since the decommissioning of the grating manufacture facility at Carl Zeiss in Oberkochen. To resolve this situation a new technological laboratory was established at the Helmholtz Zentrum Berlin, including instrumentation from Carl Zeiss. Besides the upgraded ZEISS equipment, an advanced grating production line has been developed, including a new ultra-precise ruling machine, ion etching technology as well as laser interference lithography. While the old ZEISS ruling machine GTM-6 allows ruling for a grating length up to 170 mm, the new GTM-24 will have the capacity for 600 mm (24 inch) gratings with groove densities between 50 lines mm -1 and 1200 lines mm -1 . A new ion etching machine with a scanning radiofrequency excited ion beam (HF) source allows gratings to be etched into substrates of up to 500 mm length. For a final at-wavelength characterization, a new reflectometer at a new Optics beamline at the BESSY-II storage ring is under operation. This paper reports on the status of the grating fabrication, the measured quality of fabricated items by ex situ and in situ metrology, and future development goals.

Simulation of transmitted X-rays in a polycapillary X-ray lens

Energy Technology Data Exchange (ETDEWEB)

Peng, Shiqi [The Key Laboratory of Beam Technology and Material Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Liu, Zhiguo, E-mail: liuzhiguo512@126.com [The Key Laboratory of Beam Technology and Material Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi; Wang, Kai; Yi, Longtao; Yang, Kui; Chen, Man; Wang, Jinbang [The Key Laboratory of Beam Technology and Material Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

2015-09-21

The geometrical description of capillary systems adjusted for the controlled guiding of X-rays and the basic theory of the transmission of X-rays are presented. A method of numerical calculation, based on Ray-Tracing theory, is developed to simulate the transmission efficiency of an X-ray parallel lens and the shape and size of the light spot gain from it. The simulation results for two half-lenses are in good agreement with the experimental results.

Microfocussing of synchrotron X-rays using X-ray refractive lens developed at Indus-2 deep X-ray lithography beamline

International Nuclear Information System (INIS)

Dhamgaye, V.P.; Tiwari, M.K.; Lodha, G.S.; Sawhney, K.J.S.

2014-01-01

X-ray lenses are fabricated in polymethyl methacrylate using deep X-ray lithography beamline of Indus-2. The focussing performance of these lenses is evaluated using Indus-2 and Diamond Light Source Ltd. The process steps for the fabrication of X-ray lenses and microfocussing at 10 keV at moderate and low emittance sources are compared. (author)

X pinch a point x-ray source

International Nuclear Information System (INIS)

Garg, A.B.; Rout, R.K.; Shyam, A.; Srinivasan, M.

1993-01-01

X ray emission from an X pinch, a point x-ray source has been studied using a pin-hole camera by a 30 kV, 7.2 μ F capacitor bank. The wires of different material like W, Mo, Cu, S.S.(stainless steel) and Ti were used. Molybdenum pinch gives the most intense x-rays and stainless steel gives the minimum intensity x-rays for same bank energy (∼ 3.2 kJ). Point x-ray source of size (≤ 0.5 mm) was observed using pin hole camera. The size of the source is limited by the size of the pin hole camera. The peak current in the load is approximately 150 kA. The point x-ray source could be useful in many fields like micro lithography, medicine and to study the basic physics of high Z plasmas. (author). 4 refs., 3 figs

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- ...

Compact X-ray sources: X-rays from self-reflection

Science.gov (United States)

Mangles, Stuart P. D.

2012-05-01

Laser-based particle acceleration offers a way to reduce the size of hard-X-ray sources. Scientists have now developed a simple scheme that produces a bright flash of hard X-rays by using a single laser pulse both to generate and to scatter an electron beam.

Phase-contrast X-ray imaging using an X-ray interferometer for biological imaging

Energy Technology Data Exchange (ETDEWEB)

Momose, Atsushi; Koyama, Ichiro [Tokyo Univ., Dept. of Applied Physics, Tokyo (Japan); Takeda, Tohoru; Itai, Yuji [Tsukuba Univ., Inst. of Clinical Medicine, Tsukuba, Ibaraki (Japan); Yoneyama, Akio [Hitachi Ltd., Advanced Research Laboratory, Saitama (Japan)

2002-04-01

The potential of phase-contrast X-ray imaging using an X-ray interferometer is discussed comparing with other phase-contrast X-ray imaging methods, and its principle of contrast generation is presented including the case of phase-contrast X-ray computed tomography. The status of current instrumentation is described and perspectives for practical applications are discussed. (author)

X-ray crystallography

Science.gov (United States)

2001-01-01

X-rays diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an X-ray crystallographer shines X-rays through the crystal. Unlike a single dental X-ray, which produces a shadow image of a tooth, these X-rays have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the X-rays after they diffract through the crystal. The X-rays bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.

Development of X-ray excitable luminescent probes for scanning X-ray microscopy

International Nuclear Information System (INIS)

Moronne, M.M.

1999-01-01

Transmission soft X-ray microscopy is now capable of achieving resolutions that are typically 5 times better than the best-visible light microscopes. With expected improvements in zone plate optics, an additional factor of two may be realized within the next few years. Despite the high resolution now available with X-ray microscopes and the high X-ray contrast provided by biological molecules in the soft X-ray region (λ=2-5 nm), molecular probes for localizing specific biological targets have been lacking. To circumvent this problem, X-ray excitable molecular probes are needed that can target unique biological features. In this paper we report our initial results on the development of lanthanide-based fluorescent probes for biological labeling. Using scanning luminescence X-ray microscopy (SLXM, Jacobsen et al., J. Microscopy 172 (1993) 121-129), we show that lanthanide organo-polychelate complexes are sufficiently bright and radiation resistant to be the basis of a new class of X-ray excitable molecular probes capable of providing at least a fivefold improvement in resolution over visible light microscopy. Lanthanide probes, able to bind 80-100 metal ions per molecule, were found to give strong luminescent signals with X-ray doses exceeding 10 8 Gy, and were used to label actin stress fibers and in vitro preparations of polymerized tubulin. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Projection-type X-ray microscope based on a spherical compound refractive X-ray lens

OpenAIRE

Dudchik, Yu. I.; Gary, C. K.; Park, H.; Pantell, R. H.; Piestrup, M. A.

2007-01-01

New projection- type X-ray microscope with a compound refractive lens as the optical element is presented. The microscope consists of an X-ray source that is 1-2 mm in diameter, compound X-ray lens and X-ray camera that are placed in-line to satisfy the lens formula. The lens forms an image of the X-ray source at camera sensitive plate. An object is placed between the X-ray source and the lens as close as possible to the source, and the camera shows a shadow image of the object. Spatial resol...

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.

Increasing the darkfield contrast-to-noise ratio using a deconvolution-based information retrieval algorithm in X-ray grating-based phase-contrast imaging.

Science.gov (United States)

Weber, Thomas; Pelzer, Georg; Bayer, Florian; Horn, Florian; Rieger, Jens; Ritter, André; Zang, Andrea; Durst, Jürgen; Anton, Gisela; Michel, Thilo

2013-07-29

A novel information retrieval algorithm for X-ray grating-based phase-contrast imaging based on the deconvolution of the object and the reference phase stepping curve (PSC) as proposed by Modregger et al. was investigated in this paper. We applied the method for the first time on data obtained with a polychromatic spectrum and compared the results to those, received by applying the commonly used method, based on a Fourier analysis. We confirmed the expectation, that both methods deliver the same results for the absorption and the differential phase image. For the darkfield image, a mean contrast-to-noise ratio (CNR) increase by a factor of 1.17 using the new method was found. Furthermore, the dose saving potential was estimated for the deconvolution method experimentally. It is found, that for the conventional method a dose which is higher by a factor of 1.66 is needed to obtain a similar CNR value compared to the novel method. A further analysis of the data revealed, that the improvement in CNR and dose efficiency is due to the superior background noise properties of the deconvolution method, but at the cost of comparability between measurements at different applied dose values, as the mean value becomes dependent on the photon statistics used.

The Mapping X-ray Fluorescence Spectrometer (MapX)

Science.gov (United States)

Sarrazin, P.; Blake, D. F.; Marchis, F.; Bristow, T.; Thompson, K.

2017-12-01

Many planetary surface processes leave traces of their actions as features in the size range 10s to 100s of microns. The Mapping X-ray Fluorescence Spectrometer (MapX) will provide elemental imaging at 100 micron spatial resolution, yielding elemental chemistry at a scale where many relict physical, chemical, or biological features can be imaged and interpreted in ancient rocks on planetary bodies and planetesimals. MapX is an arm-based instrument positioned on a rock or regolith with touch sensors. During an analysis, an X-ray source (tube or radioisotope) bombards the sample with X-rays or alpha-particles / gamma-rays, resulting in sample X-ray Fluorescence (XRF). X-rays emitted in the direction of an X-ray sensitive CCD imager pass through a 1:1 focusing lens (X-ray micro-pore Optic (MPO)) that projects a spatially resolved image of the X-rays onto the CCD. The CCD is operated in single photon counting mode so that the energies and positions of individual X-ray photons are recorded. In a single analysis, several thousand frames are both stored and processed in real-time. Higher level data products include single-element maps with a lateral spatial resolution of 100 microns and quantitative XRF spectra from ground- or instrument- selected Regions of Interest (ROI). XRF spectra from ROI are compared with known rock and mineral compositions to extrapolate the data to rock types and putative mineralogies. When applied to airless bodies and implemented with an appropriate radioisotope source for alpha-particle excitation, MapX will be able to analyze biogenic elements C, N, O, P, S, in addition to the cations of the rock-forming elements >Na, accessible with either X-ray or gamma-ray excitation. The MapX concept has been demonstrated with a series of lab-based prototypes and is currently under refinement and TRL maturation.

Combined optic system based on polycapillary X-ray optics and single-bounce monocapillary optics for focusing X-rays from a conventional laboratory X-ray source

Energy Technology Data Exchange (ETDEWEB)

Sun, Xuepeng; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stx@bnu.edu.cn [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Yi, Longtao; Sun, Weiyuan; Li, Fangzuo; Jiang, Bowen [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

2015-12-01

Two combined optic systems based on polycapillary X-ray optics and single-bounce monocapillary optics (SBMO) were designed for focusing the X-rays from a conventional laboratory X-ray source. One was based on a polycapillary focusing X-ray lens (PFXRL) and a single-bounce ellipsoidal capillary (SBEC), in which the output focal spot with the size of tens of micrometers of the PFXRL was used as the “virtual” X-ray source for the SBEC. The other system was based on a polycapillary parallel X-ray lens (PPXRL) and a single-bounce parabolic capillary (SBPC), in which the PPXRL transformed the divergent X-ray beam from an X-ray source into a quasi-parallel X-ray beam with the divergence of sever milliradians as the incident illumination of the SBPC. The experiment results showed that the combined optic systems based on PFXRL and SBEC with a Mo rotating anode X-ray generator with the focal spot with a diameter of 300 μm could obtain a focal spot with the total gain of 14,300 and focal spot size of 37.4 μm, and the combined optic systems based on PPXRL and SBPC with the same X-ray source mentioned above could acquire a focal spot with the total gain of 580 and focal spot size of 58.3 μm, respectively. The two combined optic systems have potential applications in micro X-ray diffraction, micro X-ray fluorescence, micro X-ray absorption near edge structure, full field X-ray microscopes and so on.

Wavelength dispersive X-ray absorption fine structure imaging by parametric X-ray radiation

International Nuclear Information System (INIS)

Inagaki, Manabu; Sakai, Takeshi; Sato, Isamu; Hayakawa, Yasushi; Nogami, Kyoko; Tanaka, Toshinari; Hayakawa, Ken; Nakao, Keisuke

2008-01-01

The parametric X-ray radiation (PXR) generator system at Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University is a monochromatic and coherent X-ray source with horizontal wavelength dispersion. The energy definition of the X-rays, which depends on the horizontal size of the incident electron beam on the generator target crystal, has been investigated experimentally by measuring the X-ray absorption near edge structure (XANES) spectra on Cu and CuO associated with conventional X-ray absorption imaging technique. The result demonstrated the controllability of the spectrum resolution of XANES by adjusting of the horizontal electron beam size on the target crystal. The XANES spectra were obtained with energy resolution of several eV at the narrowest case, which is in qualitative agreement with the energy definition of the PXR X-rays evaluated from geometrical consideration. The result also suggested that the wavelength dispersive X-ray absorption fine structure measurement associated with imaging technique is one of the promising applications of PXR. (author)

Commissioning of the soft x-ray undulator beamline at the Siam Photon Laboratory

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Hideki, E-mail: hideki@slri.or.th; Chaichuay, Sarunyu; Sudmuang, Porntip; Rattanasuporn, Surachet; Jenpiyapong, Watcharapon; Supruangnet, Ratchadaporn; Chanlek, Narong [Synchrotron Light Research Institute, Muang, Nakhon Ratchasima 30000 (Thailand); Songsiriritthigul, Prayoon [School of Physics, Suranaree University of Technology, Muang, Nakhon Ratchasima 30000 (Thailand)

2016-07-27

The synchrotron radiation from the first undulator at the Siam Photon Laboratory was characterized with the photon beam position monitors (BPMs) and grating monochromator. The soft x-ray undulator beamline employs a varied line-spacing plane grating monochromator with three interchangeable gratings. Since 2010, the beamline has delivered photons with energy of 40-160 and 220-1040 eV at the resolving power of 10,000 for user services at the two end- stations that utilize the photoemission electron spectroscopy and microscopy techniques. The undulator power-density distributions measured by the 0.05-mm wire-scan BPM were in good agreement with those in simulation. The flux-density distributions were evaluated in the red-shift measurements, which identify the central cone of radiation and its distribution. Since 2014, the operation of the other insertion devices in the storage ring has started, and consequently bought about the increases in the emittance from 41 to 61 nm·rad and the coupling constant from 4 to 11%. The local electron-orbit correction greatly improved the alignment of the electron beam in the undulator section resulting in the improvements of the photon flux and harmonics peaks of the undulator radiation.

Design of the soft x-ray tomography beamline at Taiwan photon source

Energy Technology Data Exchange (ETDEWEB)

Su, Yi-Jr, E-mail: su.yj@nsrrc.org.tw; Fu, Huang-Wen; Chung, Shih-Chun; Fung, Hok-Sum; Liu, Din-Goa; Huang, Liang-Jen; Yan, Hong-Yi; Chou, Yu-Ching; Yin, Gung-Chian; Lai, Lee-Jene [National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu, Taiwan (China)

2016-07-27

The optical design of the varied-line-spacing plane-grating monochromator for transmission full-field imaging of frozen-hydrated biological samples at NSRRC is presented. This monochromator consists of a plane mirror and three interchangeable gratings with groove densities 600, 1200 and 2400 l/mm to cover the energy range 260 – 2600 eV. The groove parameters of the varied-line-spacing plane gratings are designed to minimize the effect of coma and spherical aberration to maintain the exit slit in focus for any value of incident angle. All parameters of optical components at the beamline are verified with a ray-tracing method. In the beamline design, the calculated results from the ray-tracing codes and the expected performances are discussed.

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... are the limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray ( ... leg (shin), ankle or foot. top of page What are some common uses of the procedure? A ...

Bone X-Ray (Radiography)

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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 ...

Bone X-Ray (Radiography)

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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 ...

Bone X-Ray (Radiography)

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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 ...

Bone X-Ray (Radiography)

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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 ...

X-ray holography

International Nuclear Information System (INIS)

Faigel, G.; Tegze, M.; Belakhovsky, M.; Marchesini, S.; Bortel, G.

2003-01-01

In the last decade holographic methods using hard X-rays were developed. They are able to resolve atomic distances, and can give the 3D arrangement of atoms around a selected element. Therefore, hard X-ray holography has potential applications in chemistry, biology and physics. In this article we give a general description of these methods and discuss the developments in the experimental technique. The capabilities of hard X-ray holography are demonstrated by examples

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

Ultrashort X-ray pulse science

International Nuclear Information System (INIS)

Chin, A.H.; Lawrence Berkeley National Lab., CA

1998-01-01

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 o Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ∼ 300 fs, 30 keV (0.4 (angstrom)) 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

Anatomy of the AGN in NGC 5548. IX. Photoionized emission features in the soft X-ray spectra

Science.gov (United States)

Mao, Junjie; Kaastra, J. S.; Mehdipour, M.; Gu, Liyi; Costantini, E.; Kriss, G. A.; Bianchi, S.; Branduardi-Raymont, G.; Behar, E.; Di Gesu, L.; Ponti, G.; Petrucci, P.-O.; Ebrero, J.

2018-04-01

The X-ray narrow emission line region (NELR) of the archetypal Seyfert 1 galaxy NGC 5548 has been interpreted as a single-phase photoionized plasma that is absorbed by some of the warm absorber components. This scenario requires those overlaying warm absorber components to have larger distance (to the central engine) than the X-ray NELR, which is not fully consistent with the distance estimates found in the literature. Therefore, we reanalyze the high-resolution spectra obtained in 2013-2014 with the Reflection Grating Spectrometer (RGS) aboard XMM-Newton to provide an alternative interpretation of the X-ray narrow emission features. We find that the X-ray narrow emission features in NGC 5548 can be described by a two-phase photoionized plasma with different ionization parameters (logξ = 1.3 and 0.1) and kinematics (vout = -50 and -400 km s-1), and no further absorption by the warm absorber components. The X-ray and optical NELR might be the same multi-phase photoionized plasma. Both X-ray and optical NELR have comparable distances, asymmetric line profiles, and the underlying photoionized plasma is turbulent and compact in size. The X-ray NELR is not the counterpart of the UV/X-ray absorber outside the line of sight because their distances and kinematics are not consistent. In addition, X-ray broad emission features that we find in the spectrum can be accounted for by a third photoionized emission component. The RGS spectrum obtained in 2016 is analyzed as well, where the luminosity of most prominent emission lines (the O VII forbidden line and O VIII Lyα line) are the same (at a 1σ confidence level) as in 2013-2014.

Wide-area phase-contrast X-ray imaging using large X-ray interferometers

Energy Technology Data Exchange (ETDEWEB)

Momose, Atsushi E-mail: momose@exp.t.u-tokyo.ac.jp; Takeda, Tohoru; Yoneyama, Akio; Koyama, Ichiro; Itai, Yuji

2001-07-21

Large X-ray interferometers are developed for phase-contrast X-ray imaging aiming at medical applications. A monolithic X-ray interferometer and a separate one are studied, and currently a 25 mmx20 mm view area can be generated. This paper describes the strategy of our research program and some recent developments.

Wide-area phase-contrast X-ray imaging using large X-ray interferometers

Science.gov (United States)

Momose, Atsushi; Takeda, Tohoru; Yoneyama, Akio; Koyama, Ichiro; Itai, Yuji

2001-07-01

Large X-ray interferometers are developed for phase-contrast X-ray imaging aiming at medical applications. A monolithic X-ray interferometer and a separate one are studied, and currently a 25 mm×20 mm view area can be generated. This paper describes the strategy of our research program and some recent developments.

Bone X-Ray (Radiography)

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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 ...

Material Discriminated X-Ray CT System by Using New X-Ray Imager with Energy Discriminate Function

Directory of Open Access Journals (Sweden)

Toru Aoki

2008-04-01

Full Text Available Material discriminated X-ray CT system has been constructed by using conventional X-ray tube (white X-ray source and photon-counting X-ray imager as an application with energy band detection. We have already reported material identify X-ray CT using K-shell edge method elsewhere. In this report the principle of material discrimination was adapted the separation of electron-density and atomic number from attenuation coefficient mapping in X-ray CT reconstructed image in two wavelength X-ray CT method using white X-ray source and energy discriminated X-ray imager by using two monochrome X-ray source method. The measurement phantom was prepared as four kinds material rods (Carbon(C, Iron(Fe, Copper(Cu, Titanium(Ti rods of 3mm-diameter inside an aluminum(Al rod of 20mm-diameter. We could observed material discriminated X-ray CT reconstructed image, however, the discrimination properties were not good than two monochrome X-ray CT method. This results was could be explained because X-ray scattering, beam-hardening and so on based on white X-ray source, which could not observe in two monochrome X-ray CT method. However, since our developed CdTe imager can be detect five energy-bands at the same time, we can use multi-band analysis to decrease the least square error margin. We will be able to obtain more high separation in atomic number mapping in X-ray CT reconstructed image by using this system.

IMPLICATIONS OF X-RAY LINE VARIATIONS FOR 4U1822-371

International Nuclear Information System (INIS)

Ji, L.; Schulz, N. S.; Nowak, M. A.; Canizares, C. R.

2011-01-01

4U 1822-371 is one of the prototype accretion disk coronal sources with an orbital period of about 5.6 hr. The binary is viewed almost edge-on at a high inclination angle of 83 deg., which makes it a unique candidate to study binary orbital and accretion disk dynamics in high powered X-ray sources. We observed the X-ray source in 4U 1822-371 with the Chandra High Energy Transmission Grating Spectrometer for almost nine binary orbits. X-ray eclipse times provide an update of the orbital ephemeris. We find that our result follows the quadratic function implied by previous observations; however, it suggests a flatter trend. From the orbital line dynamics, we confirm the previous suggestion that recombination emission is located at the impact bulge of the accretion stream. Our observations show that the recombining plasma is confined to this region, and prove that it has to be a very thin layer on top of the accretion disk. Fe XXVI emission is detected at all phases and likely originates from the hot central corona which has optical depth <<1. The implied ionization parameters from both regions strongly suggest that the illuminating source is obscured with respect to the observer and is orders of magnitude brighter than what is actually observed. This is independently confirmed by the best fit of a flat power law with a high-energy cutoff and partial covering absorption with a covering fraction of about 50%. We discuss the implications of our findings with respect to the photoionized line emission and the spectral continuum on basic properties of the X-ray source.

GISAXS study of Au-coated light-induced polymer gratings

Energy Technology Data Exchange (ETDEWEB)

Castro-Colin, M., E-mail: miguel.castro-colin@bruker.com; Korolkov, D. [Bruker AXS, Rheinbrueckenstr. 49, 76187 Karlsruhe (Germany); Yadavalli, N. S. [Nanostructured Materials Lab, The University of Georgia, 30602 Athens, Georgia (United States); Mayorova, M.; Kentzinger, M. [Research Center Juelich, 52425 Juelich (Germany); Santer, S. [Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam (Germany)

2015-07-23

Surface Relief Gratings (SRGs) are inscribed in the Au-coated azobenzene containing photosensitive polymer films on a glass substrate. The structures consist of micrometer-period sinusoidal patterns of sub-micron amplitudes, formed by photo-isomerization and molecular reorientation processes in the polymer film during exposure to the light interference pattern that drove the formation of a SRG; the precursor is a stack sequence of Au, polymer, and glass. The SRG structures were exposed in GISAXS geometry to high-intensity X-ray radiation from a liquid Ga source (0.134 nm). Scattered photons were registered by a 2D detector, and their intensity distribution enabled us to characterize the structures. Analysis of the 2D patterns yielded information about the pitch of the gratings as well as the thickness of the films forming the gratings. The GISAXS experiments were carried out at the Research Center Juelich.

X-Pinch And Its Applications In X-ray Radiograph

International Nuclear Information System (INIS)

Zou Xiaobing; Wang Xinxin; Liu Rui; Zhao Tong; Zeng Naigong; Zhao Yongchao; Du Yanqiang

2009-01-01

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.

Chest X-Ray (Chest Radiography)

Science.gov (United States)

... Resources Professions Site Index A-Z X-ray (Radiography) - Chest Chest x-ray uses a very small dose ... Radiography? What is a Chest X-ray (Chest Radiography)? The chest x-ray is the most commonly performed diagnostic ...

X-ray luminescent glasses

International Nuclear Information System (INIS)

Takahashi, T.; Yamada, O.

1981-01-01

X-ray luminescent glasses comprising a divalent cation such as an alkaline earth metal or other divalent cations such as pb, cd, or zn, and certain rare earth metaphosphates are suitable as vitreous, x-ray phosphors or x-ray luminescent glass fibers in an x-ray intensifying screen. The glasses have the composition n(Mo X p2o5)((1-y)tb2o3 X yce2o3 X 3p2o5) wherein N is greater than zero but less than or equal to 16, M is an alkaline earth metal or other divalent cation such as pb, cd, or zn, and Y is greater than or equal to zero but less than one

X-ray electromagnetic application technology

International Nuclear Information System (INIS)

2011-01-01

The investigating committee aimed at research on electromagnetic fields in functional devices and X-ray fibers for efficient coherent X-ray generation and their material science, high-precision manufacturing, particularly for X-ray electromagnetic application technology from January 2006 to December 2008. In this report, we describe our research results, in particular, on the topics of synchrotron radiation and free-electron laser, Saga Synchrotron Project, X-ray waveguides and waveguide-based lens-less hard-X-ray imaging, X-ray nanofocusing for capillaries and zone plates, dispersion characteristics in photonics crystal consisting of periodic atoms for nanometer waveguides, electromagnetic characteristics of grid structures for scattering fields of nano-meter electromagnetic waves and X-rays, FDTD parallel computing of fundamental scattering and attenuation characteristics of X-ray for medical imaging diagnosis, orthogonal relations of electromagnetic fields including evanescent field in dispersive medium. (author)

Legal directives in the X-ray regulation for the field of X-ray diagnostics

International Nuclear Information System (INIS)

Huhn, Walter

2012-01-01

The operation of each X-ray device is subject to the requirements of the X-ray regulations (RoeV); for different operational modes or applications like curative diagnostics, X-ray serial examinations, X-ray radiotherapy and teleradiology different directives exist and have to be respected. The report discusses the issues licensing and notification procedures, radiation protection representative, requirements for the commissioning (teleradiology, serial X.ray examinations), technical qualification and radiation protection knowledge of physicians, technical qualification of the assistant personnel.

High-speed X-ray topography

International Nuclear Information System (INIS)

Eckers, W.; Oppolzer, H.

1977-01-01

The investigation of lattice defects in semiconductor crystals by conventional X-ray diffraction topography is very time-consuming. Exposure times can be reduced by using high-intensity X-rays and X-ray image intensifiers. The described system comprises a high-power rotating-anode X-ray tube, a remote-controlled X-ray topography camera, and a television system operating with an X-ray sensing VIDICON. System performance is demonstrated with reference to exploratory examples. The exposure time for photographic plates is reduced to 1/20 and for the X-ray TV system (resolution of the order of 30 μm) to 1/100 relative to that required when using a conventional topography system. (orig.) [de

13.1 micrometers hard X-ray focusing by a new type monocapillary X-ray optic designed for common laboratory X-ray source

Science.gov (United States)

Sun, Xuepeng; zhang, Xiaoyun; Zhu, Yu; Wang, Yabing; Shang, Hongzhong; Zhang, Fengshou; Liu, Zhiguo; Sun, Tianxi

2018-04-01

A new type of monocapillary X-ray optic, called 'two bounces monocapillary X-ray optics' (TBMXO), is proposed for generating a small focal spot with high power-density gain for micro X-ray analysis, using a common laboratory X-ray source. TBMXO is consists of two parts: an ellipsoidal part and a tapered part. Before experimental testing, the TBMXO was simulated by the ray tracing method in MATLAB. The simulated results predicted that the proposed TBMXO would produce a smaller focal spot with higher power-density gain than the ellipsoidal monocapillary X-ray optic (EMXO). In the experiment, the TBMXO performance was tested by both an optical device and a Cu target X-ray tube with focal spot of 100 μm. The results indicated that the TBMXO had a slope error of 57.6 μrad and a 13.1 μm focal spot and a 1360 gain in power density were obtained.

Effects of X-ray tube parameters on thickness measure precision in X-ray profile gauge

International Nuclear Information System (INIS)

Miao Jichen; Wu Zhifang; Xing Guilai

2011-01-01

Instantaneous profile gauge technology has been widely used in metallurgy industry because it can on-line get the profile of steel strip. It has characters of high measure precision and wide measure range, but the X-ray tube parameters only can be set few different values during measurement. The relations of thickness measure precision and X-ray tube current, X-ray tube voltage were analyzed. The results show that the X-ray tube current affects the thickness measure precision and the X-ray tube voltage determines the thickness measure range. The method of estimating the X-ray current by thickness measure precision was provided in the end. This method is the base of X-ray source selection and X-ray source parameter's setting in the instantaneous profile gauge. (authors)

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small ...

X-Ray Exam: Hip

Science.gov (United States)

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

X-Ray Exam: Ankle

Science.gov (United States)

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

Shield device for controlling the dose of x-rays applied in an x-ray machine

International Nuclear Information System (INIS)

Charrier, P.

1983-01-01

This invention provides an improved shield for use with an x-ray machine. The shield can control the dose of x-rays applied by the machine in different areas without affecting the power of the x-rays. This is achieved with a shield especially designed and positioned to intercept with x-rays for longer or shorter periods in different areas during the taking of the picture, but not for the whole period of time necessary for taking this picture. Each area of the subject being x-rayed is exposed to full power x-rays. However, owing to the shield, the areas that require smaller dose receive these full power x-rays for a shorter portion of the time required to take the picture while the other areas that require larger dose of x-rays, receive the full power x-rays for a longer portion of the full period of time required to take the picture. To ensure this differential exposure, the shield is placed through the path of the x-rays and rotated about an axis which is generally transverse to the direction of travel of the x-rays to cut out some of said x-rays for different portions of the period of time necessary for taking the picture. The shield is preferably shaped to intercept x-rays for a longer period in some areas than in others depending on the required doses. A plurality of differently shaped shields can be provided to suit different picture taking situations

X-Ray Exam: Cervical Spine

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español X-Ray Exam: Cervical Spine KidsHealth / For Parents / X-Ray ... MRI): Lumbar Spine Broken Bones Getting an X-ray (Video) X-Ray (Video) View more Partner Message About Us ...

Differences of X-ray exposure between X-ray diagnostics with a conventional X-ray screen-system and with an image-intensifier-television-unit

International Nuclear Information System (INIS)

Loehr, H.; Vogel, H.; Reinhart, J.; Jantzen, R.

1977-01-01

During X-ray diagnostics of patients in the II. Medizinische Poliklinik the X-ray exposure was determined. It corresponded to the data described in literature. Two groups were compared: 518 patients examined with a conventional X-ray screen-system and 642 patients examined with an image-intensifier-television-system. The results demonstrated that with exception of thoracical X-ray examination the replacing of the old system by the television system brought a remarkable increase of the X-ray exposure. The doses depended of the patients constitution to a high degree. (orig.) [de

Applications of phase-contrast x-ray imaging to medicine using an x-ray interferometer

Science.gov (United States)

Momose, Atsushi; Yoneyama, Akio; Takeda, Tohoru; Itai, Yuji; Tu, Jinhong; Hirano, Keiichi

1999-10-01

We are investigating possible medical applications of phase- contrast X-ray imaging using an X-ray interferometer. This paper introduces the strategy of the research project and the present status. The main subject is to broaden the observation area to enable in vivo observation. For this purpose, large X-ray interferometers were developed, and 2.5 cm X 1.5 cm interference patterns were generated using synchrotron X-rays. An improvement of the spatial resolution is also included in the project, and an X-ray interferometer designed for high-resolution phase-contrast X-ray imaging was fabricated and tested. In parallel with the instrumental developments, various soft tissues are observed by phase- contrast X-ray CT to find correspondence between the generated contrast and our histological knowledge. The observation done so far suggests that cancerous tissues are differentiated from normal tissues and that blood can produce phase contrast. Furthermore, this project includes exploring materials that modulate phase contrast for selective imaging.

X-ray spectral meter of high voltages for X-ray apparatuses

International Nuclear Information System (INIS)

Zubkov, I.P.; Larchikov, Yu.V.

1993-01-01

Design of the X-ray spectral meter of high voltages (XRSMHV) for medical X-ray apparatuses permitting to conduct the voltage measurements without connection to current circuits. The XRSMHV consists of two main units: the detector unit based on semiconductor detector and the LP4900B multichannel analyzer (Afora, Finland). The XRSMYV was tested using the pilot plant based on RUM-20 X-ray diagnostic apparatus with high-voltage regulator. It was shown that the developed XRSMHV could be certify in the range of high constant voltages form 40 up to 120 kV with the basic relative error limits ±0.15%. The XRSMHV is used at present as the reference means for calibration of high-voltage medical X-ray equipment

Feasibility of using continuous X-ray to simulate cable response under X-ray environment

International Nuclear Information System (INIS)

Ma Liang; Zhou Hui; Cheng Yinhui; Wu Wei; Li Jinxi; Zhao Mo; Guo Jinghai

2014-01-01

The mechanism and simulating method of cable response induced by X-ray were researched, and the relationship of cable response irradiated by continuous and pulsed X-ray was analyzed. A one-dimension model of strip line irradiation response of X-ray was given, which includes the gap between cable shield and dielectric, and induced conductivity in cable dielectric. The calculation result using the model indicates that the cable responses of continuous and rectangular-pulsed X-ray have the similar current waveform and the same gap voltages. Therefore, continuous X-ray can be used to research some cable responses of pulsed X-ray irradiation under the mechanism described in the one-dimension model. (authors)

X-ray cardiovascular examination apparatus

International Nuclear Information System (INIS)

1977-01-01

An X-ray source is mounted in an enclosure for angulating longitudinally about a horizontal axis. An X-ray-permeable, patient-supporting table is mounted on the top of the enclosure for executing lateral and longitudinal movements. An X-ray image-receiving device such as an X-ray image intensifier is mounted above the table on a vertically movable arm which is on a longitudinally movable carriage. Electric control means are provided for angulating the X-ray source and image intensifier synchronously as the image intensifier system is shifted longitudinally or vertically such that the central ray from the X-ray source is kept intensifier

Gaining efficiency and resolution in soft X-ray emission spectrometers thanks to directly illuminated CCD detectors

International Nuclear Information System (INIS)

Dinardo, M.E.; Piazzalunga, A.; Braicovich, L.; Bisogni, V.; Dallera, C.; Giarda, K.; Marcon, M.; Tagliaferri, A.; Ghiringhelli, G.

2007-01-01

The back-illuminated charge coupled devices (CCD) are suitable for soft X-ray photon detection. Their nominal performances suggest that they can boost both efficiency and resolving power of X-ray spectrometers based on diffraction gratings and two-dimensional position sensitive detectors. We tested the performances of two commercially available CCDs, intended to replace a more traditional microchannel plate (MCP) detector. Our tests show that the devices have excellent performances in terms of dark current, response linearity, detection efficiency and spatial resolution. We observed that the CCDs have better efficiency (more than 10 times) and better resolution (∼3 times) than the MCP. Moreover we found an intrinsic limit for the spatial resolution, which is almost independent of the detector pixel size and is estimated around 25 μm

Effect of Electric Voltage and Current of X-ray Chamber on the Element inthe Zirconium Alloy Analysis X-ray by X-ray Fluorescence

International Nuclear Information System (INIS)

Yusuf-Nampira; Narko-Wibowo, L; Rosika-Krisnawati; Nudia-Barenzani

2000-01-01

The using of x-ray fluorescence in the chemical analysis depend heavilyon the parameters of x-ray chamber, for examples : electric voltage andelectric current. That parameter give effect in the result of determine ofSn, Cr, Fe and Ni in the zirconium alloy. 20 kV electric voltages are used onthe Mo x-ray chamber shall product x-ray of zirconium in the sample materialcan give effect in the stability of the analysis result (deviation more than5%). The result of analysis of elements in the zirconium alloy shall givedeviation less than 5% when using of electric voltage of the x-ray chamberless than 19 kV. The sensitivity of analysis can be reached by step upelectric current of x-ray chamber. (author)

Compound refractive X-ray lens

International Nuclear Information System (INIS)

Nygren, D.R.; Cahn, R.; Cederstrom, B.; Danielsson, M.; Vestlund, J.

2000-01-01

An apparatus and method are disclosed for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point

Compound refractive X-ray lens

Science.gov (United States)

Nygren, David R.; Cahn, Robert; Cederstrom, Bjorn; Danielsson, Mats; Vestlund, Jonas

2000-01-01

An apparatus and method for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point.

X-ray diffraction device comprising cooling medium connections provided on the x-ray tube

NARCIS (Netherlands)

1996-01-01

An X-ray diffraction device comprises a water-cooled X-ray tube which exhibits a line focus as well as, after rotation through 90 DEG , a point focus. Contrary to customary X-ray tubes, the cooling water is not supplied via the housing (12) in which the X-ray tube is mounted, but the cooling water

Chest X-Ray

Medline Plus

Full Text Available ... some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to your health. While a chest x-ray use a ... posted: How to Obtain and Share ...

Soft x-ray streak cameras

International Nuclear Information System (INIS)

Stradling, G.L.

1988-01-01

This paper is a discussion of the development and of the current state of the art in picosecond soft x-ray streak camera technology. Accomplishments from a number of institutions are discussed. X-ray streak cameras vary from standard visible streak camera designs in the use of an x-ray transmitting window and an x-ray sensitive photocathode. The spectral sensitivity range of these instruments includes portions of the near UV and extends from the subkilovolt x- ray region to several tens of kilovolts. Attendant challenges encountered in the design and use of x-ray streak cameras include the accommodation of high-voltage and vacuum requirements, as well as manipulation of a photocathode structure which is often fragile. The x-ray transmitting window is generally too fragile to withstand atmospheric pressure, necessitating active vacuum pumping and a vacuum line of sight to the x-ray signal source. Because of the difficulty of manipulating x-ray beams with conventional optics, as is done with visible light, the size of the photocathode sensing area, access to the front of the tube, the ability to insert the streak tube into a vacuum chamber and the capability to trigger the sweep with very short internal delay times are issues uniquely relevant to x-ray streak camera use. The physics of electron imaging may place more stringent limitations on the temporal and spatial resolution obtainable with x-ray photocathodes than with the visible counterpart. Other issues which are common to the entire streak camera community also concern the x-ray streak camera users and manufacturers

Portable X-ray fluorescence analyzer of high sensitivity using X-ray tube excitation

International Nuclear Information System (INIS)

Vatai, E.; Ando, L.

1982-01-01

A review of the three main methods of X-ray fluorescence analysis and their problems is given. The attainable accuracy and effectiveness of each method are discussed. The main properties of portable X-ray analyzers required by the industry are described. The results and experiences of R and D activities in ATOMKI (Debrecen, Hungary) for developing portable X-ray analyzers are presented. The only way for increasing the accuracy and decreasing the measuring time is the application of X-ray tube excitation instead of radioactive sources. The new ATOMKI equipment presently under construction and patenting uses X-ray tube excitation; it will increase the accuracy of concentration determination by one order of magnitude. (D.Gy.)

X ray Production. Chapter 5

Energy Technology Data Exchange (ETDEWEB)

Nowotny, R. [Medical University of Vienna, Vienna (Austria)

2014-09-15

The differential absorption of X rays in tissues and organs, owing to their atomic composition, is the basis for the various imaging methods used in diagnostic radiology. The principles in the production of X rays have remained the same since their discovery. However, much refinement has gone into the design of X ray tubes to achieve the performance required for today’s radiological examinations. In this chapter, an outline of the principles of X ray production and a characterization of the radiation output of X ray tubes will be given. The basic processes producing X rays are dealt with in Section 1.4.

X-ray apparatus

International Nuclear Information System (INIS)

Sell, L.J.

1981-01-01

A diagnostic x-ray device, readily convertible between conventional radiographic and tomographic operating modes, is described. An improved drive system interconnects and drives the x-ray source and the imaging device through coordinated movements for tomography

X-ray astronomy 2000: Wide field X-ray monitoring with lobster-eye telescopes

International Nuclear Information System (INIS)

Inneman, A.; Hudec, R.; Pina, L.; Gorenstein, P.

2001-01-01

The recently available first prototypes of innovative very wide field X-ray telescopes of Lobster-Eye type confirm the feasibility to develop such flight instruments in a near future. These devices are expected to allow very wide field (more than 1000 square degrees) monitoring of the sky in X-rays (up to 10 keV and perhaps even more) with faint limits. We will discuss the recent status of the development of very wide field X-ray telescopes as well as related scientific questions including expected major contributions such as monitoring and study of X-ray afterglows of Gamma Ray Bursts

A laboratory-based hard x-ray monochromator for high-resolution x-ray emission spectroscopy and x-ray absorption near edge structure measurements

Energy Technology Data Exchange (ETDEWEB)

Seidler, G. T., E-mail: seidler@uw.edu; Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R. [Physics Department, University of Washington, Seattle, Washington 98195-1560 (United States)

2014-11-15

We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ∼5 keV to ∼10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10{sup 6}–10{sup 7} photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species.

Illumination system for X-ray lithography

International Nuclear Information System (INIS)

Buckley, W.D.

1989-01-01

An X-ray lithography system is described, comprising: a point source of X-Ray radiation; a wafer plane disposed in spaced relation to the point source of X-Ray radiation; a mask disposed between the point source of X-Ray radiation and the wafer plane whereby X-Ray radiation from the point source of X-ray radiation passes through the mask to the water plane; and X-Ray absorbent means mounted between the point source of X-Ray radiation and the wafer plane, the X-Ray absorbent means being of quadratically absorption from maximum absorption at the center to minimum absorption at the edge so as to have a radial absorption gradient profile to compensate for radial flux variation of the X-Ray radiation

An X-ray and optical study of the ultracompact X-ray binary A 1246-58

NARCIS (Netherlands)

in 't Zand, J.J.M.; Bassa, C.G.; Jonker, P.G.; Keek, L.; Verbunt, F.W.M.; Méndez, M.; Markwardt, C.B.

2008-01-01

Results are discussed of an X-ray and optical observation campaign of the low-mass X-ray binary A 1246-58 performed with instruments on Satellite per Astronomia X ("BeppoSAX"), the Rossi X-ray Timing Explorer (RXTE), the X-ray Multi-mirror Mission ("XMM-Newton"), the Swift mission, and the Very

X-ray - skeleton

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/003381.htm X-ray - skeleton To use the sharing features on this ... Degenerative bone conditions Osteomyelitis Risks There is low radiation exposure. X-rays machines are set to provide the smallest ...

Extremity x-ray

Science.gov (United States)

... page: //medlineplus.gov/ency/article/003461.htm Extremity x-ray To use the sharing features on this page, ... in the body Risks There is low-level radiation exposure. X-rays are monitored and regulated to provide the ...

Chest X-Ray

Medline Plus

Full Text Available ... X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey Rubin, a radiologist ... about chest x-rays, visit Radiology Info dot org. Thank you for your time! Spotlight Recently posted: ...

Bone X-Ray (Radiography)

Medline Plus

Full Text Available ... The x-ray tube is connected to a flexible arm that is extended over the patient while an x-ray film holder or image recording plate is placed beneath the patient. top of page How does the procedure work? X-rays are a form of radiation like ...

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.

X-ray filtration apparatus

International Nuclear Information System (INIS)

Thompson, G.

1992-01-01

This invention relates to an X-ray shielding support device. In spite of considerable development in X-ray taking techniques, a need still exists for effective shielding, inter alia, to compensate for variations in the thickness, density and the absorption properties of the object being studied. By appropriate shielding, the X-ray image produced is of sufficient detail, contrast and intensity over its entire area to constitute a useful diagnostic aid. It is also desirable to subject the patient to the smallest possible X-ray dosage. 4 figs

DETECTING THE WARM-HOT INTERGALACTIC MEDIUM THROUGH X-RAY ABSORPTION LINES

Energy Technology Data Exchange (ETDEWEB)

Yao Yangsen; Shull, J. Michael; Cash, Webster [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Wang, Q. Daniel, E-mail: yaoys@colorado.edu [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)

2012-02-20

The warm-hot intergalactic medium (WHIM) at temperatures 10{sup 5}-10{sup 7} K is believed to contain 30%-50% of the baryons in the local universe. However, all current X-ray detections of the WHIM at redshifts z > 0 are of low statistical significance ({approx}< 3{sigma}) and/or controversial. In this work, we aim to establish the detection limits of current X-ray observatories and explore requirements for next-generation X-ray telescopes for studying the WHIM through X-ray absorption lines. We analyze all available grating observations of Mrk 421 and obtain spectra with signal-to-noise ratios (S/Ns) of {approx}90 and 190 per 50 mA spectral bin from Chandra and XMM-Newton observations, respectively. Although these spectra are two of the best ever collected with Chandra and XMM-Newton, we cannot confirm the two WHIM systems reported by Nicastro et al. in 2005. Our bootstrap simulations indicate that spectra with such high S/N cannot constrain the WHIM with O VII column densities N{sub Ovii}{approx}10{sup 15} cm{sup -2} (corresponding to an equivalent width of 2.5 mA for a Doppler velocity of 50 km s{sup -1}) at {approx}> 3{sigma} significance level. The simulation results also suggest that it would take >60 Ms for Chandra and 140 Ms for XMM-Newton to measure the N{sub Ovii} at {>=}4{sigma} from a spectrum of a background QSO with flux of {approx}0.2 mCrab (1 Crab = 2 Multiplication-Sign 10{sup -8} erg s{sup -1} cm{sup -2} at 0.5-2 keV). Future X-ray spectrographs need to be equipped with spectral resolution R {approx} 4000 and effective area A {>=} 100 cm{sup 2} to accomplish the similar constraints with an exposure time of {approx}2 Ms and would require {approx}11 Ms to survey the 15 QSOs with flux {approx}> 0.2 mCrab along which clear intergalactic O VI absorbers have been detected.

Phase-contrast X-ray CT

Energy Technology Data Exchange (ETDEWEB)

Momose, Atsushi [Hitachi Ltd., Saitama (Japan). Advanced Research Laboratory; Takeda, Tohoru; Itai, Yuji

1995-12-01

Phase-contrast X-ray computed tomography (CT) enabling the observation of biological soft tissues without contrast enhancement has been developed. The X-ray phase shift caused by an object is measured and input to a standard CT reconstruction algorithm. A thousand times increase in the image sensitivity to soft tissues is achieved compared with the conventional CT using absorption contrast. This is because the X-ray phase shift cross section of light elements is about a thousand times larger than the absorption cross section. The phase shift is detected using an X-ray interferometer and computer analyses of interference patterns. Experiments were performed using a synchrotron X-ray source. Excellent image sensitivity is demonstrated in the observation of cancerous rabbit liver. The CT images distinguish cancer lesion from normal liver tissue and, moreover, visualize the pathological condition in the lesion. Although the X-ray energy employed and the present observation area size are not suitable for medical applications as they are, phase-contrast X-ray CT is promising for investigating the internal structure of soft tissue which is almost transparent for X-rays. The high sensitivity also provides the advantage of reducing X-ray doses. (author).

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

X-ray apparatus

International Nuclear Information System (INIS)

Bernstein, S.; Stagg, L.; Lambert, T.W.; Griswa, P.J.

1976-01-01

A patient support system for X-ray equipment in arteriographic studies of the heart is described in detail. The support system has been designed to overcome many of the practical problems encountered in using previous types of arteriographic X-ray equipment. The support system is capable of horizontal movement and, by a series of shafts attached to the main support system, the X-ray source and image intensifier or detector may be rotated through the same angle. The system is highly flexible and details are given of several possible operational modes. (U.K.)

Comparative study of radiation dose between digital panoramic X-ray unit and general panoramic X-ray unit

International Nuclear Information System (INIS)

Li Qingshan; Duan Tao; Wang Xiaoyun; Zhao Li; Dong Jian; Wei Lei

2010-01-01

Objective: To compare the actual dose of patients who receive the same medical practice by either digital panoramic X-ray unit and general panoramic X-ray unit and give evidence for better selection of oral X-ray examination method. Methods: Round sheet lithium fluoride (LiF) thermoluminescent dosimeters (TLD) were used. The experiment was divided into natural background contrast group, general panoramic X-ray children group, general panoramic X-ray adults group, digital panoramic X-ray children group and digital panoramic X-ray adults group. The dosimeter of natural background radiation was placed at the office of the doctor, the dosimeters of general panoramic X-ray children group and general panoramic X-ray adults group were irradiated by different conditions according to the clinical application of panoramic X-ray to children and adults, the dosimeters of digital panoramic X-ray children group and digital panoramic X-ray adults group were irradiated by different conditions according to the clinical application of digital panoramic X-ray to children and adults. The thermoluminescent dosimeter was used to count and calculate the exposure doses in various groups. Results: The dose of children exposed in general panoramic X-ray unit was 1.28 times of that in digital panoramic X-ray unit, there was significant difference (t=6.904, P<0.01). The dose of adults exposed in general panoramic X-ray unit was 1.55 times of that in the digital panoramic X-ray unit, there also was significant difference (t=-11.514. P< 0.01). Conclusion: The digital panoramic X-ray unit can reduce the dose of patients, so the digital panoramic X-ray unit should be used as far as possible. (authors)

A zone plate soft x-ray microscope using monochromatized undulator radiation at the beamline NE1B of the TRISTAN Accumulation Ring

International Nuclear Information System (INIS)

Wang, J.; Kagoshima, Y.; Miyahara, T.; Ando, M.; Aoki, S.; Anderson, E.; Attwood, D.; Kern, D.

1995-01-01

A soft x-ray microscope has been developed at the beamline NE1B of the 6.5-GeV TRISTAN Accumulation Ring (AR). It makes use of undulator radiation as its source and a zone plate with the outermost zone width of 50 nm as its imaging element. It has two main features. First, the undulator radiation is monochromatized by a grazing incidence grating monochromator to match to the monochromaticity requirement of the zone plate. Second, a visible light prefocus unit consisting of two objectives has been designed and installed in the x-ray microscope. The x-ray optical system of the microscope can be adjusted easily, quickly, and precisely by using this unit. The microscope can resolve 55-nm lines and spaces in a zone plate test pattern

Nanoparticle-Assisted Scanning Focusing X-Ray Therapy with Needle Beam X Rays.

Science.gov (United States)

Davidson, R Andrew; Guo, Ting

2016-01-01

In this work, we show a new therapeutic approach using 40-120 keV X rays to deliver a radiation dose at the isocenter located many centimeters below the skin surface several hundred times greater than at the skin and how this dose enhancement can be augmented with nanomaterials to create several thousand-fold total dose enhancement effect. This novel approach employs a needle X-ray beam directed at the isocenter centimeters deep in the body while continuously scanning the beam to cover a large solid angle without overlapping at the skin. A Monte Carlo method was developed to simulate an X-ray dose delivered to the isocenter filled with X-ray absorbing and catalytic nanoparticles in a water phantom. An experimental apparatus consisting of a moving plastic phantom irradiated with a stationary 1 mm needle X-ray beam was built to test the theoretical predictions. X-ray films were used to characterize the dose profiles of the scanning X-ray apparatus. Through this work, it was determined that the X-ray dose delivered to the isocenter in a treatment voxel (t-voxel) underneath a 5 cm deep high-density polyethylene (HDPE) phantom was 295 ± 48 times greater than the surface dose. This measured value was in good agreement with the theoretical predicted value of 339-fold. Adding X-ray-absorbing nanoparticles, catalytic nanoparticles or both into the t-voxel can further augment the dose enhancement. For example, we predicted that adding 1 weight percentage (wp) of gold into water could increase the effective dose delivered to the target by onefold. Dose enhancement using 1 mm X-ray beam could reach about 1,600-fold in the t-voxel when 7.5 wp of 88 nm diameter silica-covered gold nanoparticles were added, which we showed in a previously published study can create a dose enhancement of 5.5 ± 0.46-fold without scanning focusing enhancement. Based on the experimental data from that study, mixing 0.02 wp 2.5 nm diameter small tetrakis hydroxymethyl phosphonium chloride (THPC

X-ray astronomy

International Nuclear Information System (INIS)

Narayanan, M.S.

1976-01-01

The deployment of detectors outside the deleterious effects of the atmosphere by sending them in space vehicles, has been explained. This has thrown open the entire spectrum of the electromagnetic and particle radiation to direct observations, thus enlarging the vistas of the field of astronomy and astrophysics. The discovery of strong emitters of X-rays such as SCO X-1, NorX-2, transient sources such as Cen X-2, Cen X-4, Cen X-1, Supernova remnants Tan X-1, etc., are reported. The background of the X-ray spectrum as measured during two rocket flights over Thumba, India is presented. (K.B.)

Application of X-ray CCD camera in X-ray spot diagnosis of rod-pinch diode

International Nuclear Information System (INIS)

Song Yan; Zhou Ming; Song Guzhou; Ma Jiming; Duan Baojun; Han Changcai; Yao Zhiming

2015-01-01

The pinhole imaging technique is widely used in the measurement of X-ray spot of rod-pinch diode. The X-ray CCD camera, which was composed of film, fiber optic taper and CCD camera, was employed to replace the imaging system based on scintillator, lens and CCD camera in the diagnosis of X-ray spot. The resolution of the X-ray CCD camera was studied. The resolution is restricted by the film and is 5 lp/mm in the test with Pb resolution chart. The frequency is 1.5 lp/mm when the MTF is 0.5 in the test with edge image. The resolution tests indicate that the X-ray CCD camera can meet the requirement of the diagnosis of X-ray spot whose scale is about 1.5 mm when the pinhole imaging magnification is 0.5. At last, the image of X-ray spot was gained and the restoration was implemented in the diagnosis of X-ray spot of rod-pinch diode. (authors)

Scintillating ribbon x-ray detector

International Nuclear Information System (INIS)

Kinchen, B.E.; Rogers, A.

1995-01-01

A patent in the early 1970's by Aerojet Corporation in Sacramento, CA put forth the idea of using an array of scintillating fibers for x-ray detection and imaging. In about 1975, Pratt and Whitney Aircraft in East Hartford, CT designed and manufactured an imaging system based on the patent. The device was 1.75 in thick in the direction of the x-ray beam and about 4 in. by 4 in. square. The device was used with a 8 MeV x-ray source to image and measure internal clearances within operating aircraft, gas turbines engines. There are significant advantages of fiber optic detectors in x-ray detection. However, the advantages are often outweighed by the disadvantages. Two of the advantages of scintillating fiber optic x-ray detectors are: (1) high limiting spatial frequency -- between 20 and 25 lp/mm; and (2) excellent x-ray stopping power -- they can be made thick and retain spatial resolution. In traditional fiber optic detectors the x-rays are oriented parallel to the long axis of the fiber. For the scintillating ribbon x-ray sensor, the x-rays are oriented normal to the fiber long axis. This ribbon sensor technique has a number of advantages over the two current radiographic techniques digital x-radiography and x-ray film: The main advantage the ribbon has is size and shape. It can be as thin as 0.05 in., virtually any width or length, and flexible. Once positioned in a given location, 20 to 100 square inches of the object being inspected can be imaged with a single x-ray beam sweep. It is clear that conventional digital cameras do not lend themselves to placement between walls of aircraft structures or similar items requiring x-ray inspections. A prototype scintillating ribbon x-ray sensor has been fabricated and tested by Synergistic Detector Designs. Images were acquired on corrosion test panels of aluminum fabricated by Iowa State University

A Massive X-ray Outflow From The Quasar PDS 456

Science.gov (United States)

Reeves, J. N.; O'Brien, P. T.; Ward, M. J.

2003-01-01

We report on XMM-Newton spectroscopic observations of the luminous, radio-quiet quasar PDS 456. The hard X-ray spectrum of PDS 456 shows a deep absorption trough (constituting 50% of the continuum) at energies above 7 keV in the quasar rest frame, which can be attributed to a series of blue-shifted K-shell absorption edges due to highly ionized iron. The higher resolution soft X-ray grating RGS spectrum exhibits a broad absorption line feature near 1 keV, which can be modeled by a blend of L-shell transitions from highly ionized iron (Fe XVII - XXIV). An extreme outflow velocity of approx. 50000 km/s is required to model the K and L shell iron absorption present in the XMM-Newton data. Overall, a large column density (N(sub H) = 5 x 10(exp 23)/sq cm) of highly ionized gas (log xi = 2.5) is required in PDS 456. A large mass outflow rate of approx. 10 solar mass/year (assuming a conservative outflow covering factor of 0.1 steradian) is derived, which is of the same order as the overall mass accretion rate in PDS 456. This represents a substantial fraction (approx. 10%) of the quasar energy budget, whilst the large column and outflow velocity place PDS 456 towards the extreme end of the broad absorption line quasar population.

Center for X-Ray Optics, 1992

International Nuclear Information System (INIS)

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

JEM-X: The X-ray monitor on INTEGRAL

DEFF Research Database (Denmark)

Budtz-Jørgensen, Carl; Lund, Niels; Westergaard, Niels Jørgen Stenfeldt

2004-01-01

The INTEGRAL X-ray monitor, JEM-X, (together with the two gamma ray instruments, SPI and IBIS) provides simultaneous imaging with arcminute angular resolution in the 3-35 keV band. The good angular resolution and low energy response of JEM-X plays an important role in the detection and identifica......The INTEGRAL X-ray monitor, JEM-X, (together with the two gamma ray instruments, SPI and IBIS) provides simultaneous imaging with arcminute angular resolution in the 3-35 keV band. The good angular resolution and low energy response of JEM-X plays an important role in the detection...

X ray spectra of X Per. [oso-8 observations

Science.gov (United States)

Becker, R. H.; Boldt, E. A.; Holt, S. S.; Pravdo, S. H.; Robinson-Saba, J.; Serlemitsos, P. J.; Swank, J. H.

1978-01-01

The cosmic X-ray spectroscopy experiment on OSO-8 observed X Per for twenty days during two observations in Feb. 1976 and Feb. 1977. The spectrum of X Per varies in phase with its 13.9 min period, hardening significantly at X-ray minimum. Unlike other X-ray binary pulsar spectra, X Per's spectra do not exhibit iron line emission or strong absorption features. The data show no evidence for a 22 hour periodicity in the X-ray intensity of X Per. These results indicate that the X-ray emission from X Per may be originating from a neutron star in a low density region far from the optically identified Be star.

JEM-X: The X-ray monitor on INTEGRAL

DEFF Research Database (Denmark)

Lund, Niels; Budtz-Jørgensen, Carl; Westergaard, Niels Jørgen Stenfeldt

1999-01-01

and identification of gamma ray sources as well as in the analysis and scientific interpretation of the combined X-ray and gamma ray data. JEM-X is a coded aperture X-ray telescope consisting of two identical detectors. Each detector has a sensitive area of 500 cm(2), and views the sky (6.6 deg FOV, FWHM) through...

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.

Effects of X-Ray Dose On Rhizosphere Studies Using X-Ray Computed Tomography

Science.gov (United States)

Zappala, Susan; Helliwell, Jonathan R.; Tracy, Saoirse R.; Mairhofer, Stefan; Sturrock, Craig J.; Pridmore, Tony; Bennett, Malcolm; Mooney, Sacha J.

2013-01-01

X-ray Computed Tomography (CT) is a non-destructive imaging technique originally designed for diagnostic medicine, which was adopted for rhizosphere and soil science applications in the early 1980s. X-ray CT enables researchers to simultaneously visualise and quantify the heterogeneous soil matrix of mineral grains, organic matter, air-filled pores and water-filled pores. Additionally, X-ray CT allows visualisation of plant roots in situ without the need for traditional invasive methods such as root washing. However, one routinely unreported aspect of X-ray CT is the potential effect of X-ray dose on the soil-borne microorganisms and plants in rhizosphere investigations. Here we aimed to i) highlight the need for more consistent reporting of X-ray CT parameters for dose to sample, ii) to provide an overview of previously reported impacts of X-rays on soil microorganisms and plant roots and iii) present new data investigating the response of plant roots and microbial communities to X-ray exposure. Fewer than 5% of the 126 publications included in the literature review contained sufficient information to calculate dose and only 2.4% of the publications explicitly state an estimate of dose received by each sample. We conducted a study involving rice roots growing in soil, observing no significant difference between the numbers of root tips, root volume and total root length in scanned versus unscanned samples. In parallel, a soil microbe experiment scanning samples over a total of 24 weeks observed no significant difference between the scanned and unscanned microbial biomass values. We conclude from the literature review and our own experiments that X-ray CT does not impact plant growth or soil microbial populations when employing a low level of dose (<30 Gy). However, the call for higher throughput X-ray CT means that doses that biological samples receive are likely to increase and thus should be closely monitored. PMID:23840640

Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis

International Nuclear Information System (INIS)

Chen, J.R.; Gordon, B.M.; Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Chao, E.C.T.; Minkin, J.A.

1984-01-01

The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of synchrotron radiation include experiments in synchrotron x-ray fluorescence (SXRF) analysis and extended x-ray absorption fine structure (EXAFS) analysis. New synchrotron radiation x-ray microprobes for elemental analysis in the parts per billion range are under construction at several laboratories. 76 references, 24 figures

X-Rays, Pregnancy and You

Science.gov (United States)

... Emitting Products and Procedures Medical Imaging Medical X-ray Imaging X-Rays, Pregnancy and You Share Tweet Linkedin Pin it ... the decision with your doctor. What Kind of X-Rays Can Affect the Unborn Child? During most x- ...

Stellar X-ray sources

International Nuclear Information System (INIS)

Katz, J.I.; Washington Univ., St. Louis, MO

1988-01-01

I Review some of the salient accomplishments of X-rap studies of compact objects. Progress in this field has closely followed the improvement of observational methods, particularly in angular resolution and duration of exposure. Luminous compact X-ray sources are accreting neutron stars or black holes. Accreting neutron stars may have characteristic temporal signatures, but the only way to establish that an X-ray source is a black hole is to measure its mass. A rough phenomenological theory is succesful, but the transport of angular momentum in accretion flows is not onderstood. A number of interesting complications have been observed, including precessing accretion discs, X-ray bursts, and the acceleration of jets in SS433. Many puzzles remain unsolved, including the excitation of disc precession, the nature of the enigmatic A- and gamma-ray source Cyg X-3, the mechanism by which slowly spinning accreting neutron stars lose angular momentum, and the superabundance of X-ray sources in globular clusters. 41 refs.; 5 figs

Si K EDGE STRUCTURE AND VARIABILITY IN GALACTIC X-RAY BINARIES

Energy Technology Data Exchange (ETDEWEB)

Schulz, Norbert S.; Corrales, Lia; Canizares, Claude R. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2016-08-10

We survey the Si K edge structure in various absorbed Galactic low-mass X-ray binaries (LMXBs) to study states of silicon in the inter- and circum-stellar medium. The bulk of these LMXBs lie toward the Galactic bulge region and all have column densities above 10{sup 22} cm{sup −2}. The observations were performed using the Chandra High Energy Transmission Grating Spectrometer. The Si K edge in all sources appears at an energy value of 1844 ± 0.001 eV. The edge exhibits significant substructure that can be described by a near edge absorption feature at 1849 ± 0.002 eV and a far edge absorption feature at 1865 ± 0.002 eV. Both of these absorption features appear variable with equivalent widths up to several mÅ. We can describe the edge structure using several components: multiple edge functions, near edge absorption excesses from silicates in dust form, signatures from X-ray scattering optical depths, and a variable warm absorber from ionized atomic silicon. The measured optical depths of the edges indicate much higher values than expected from atomic silicon cross sections and interstellar medium abundances, and they appear consistent with predictions from silicate X-ray absorption and scattering. A comparison with models also indicates a preference for larger dust grain sizes. In many cases, we identify Si xiii resonance absorption and determine ionization parameters between log ξ = 1.8 and 2.8 and turbulent velocities between 300 and 1000 km s{sup −1}. This places the warm absorber in close vicinity of the X-ray binaries. In some data, we observe a weak edge at 1.840 keV, potentially from a lesser contribution of neutral atomic silicon.

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.;

Charge collection and absorption-limited x-ray sensitivity of pixellated x-ray detectors

International Nuclear Information System (INIS)

Kabir, M. Zahangir; Kasap, S.O.

2004-01-01

The charge collection and absorption-limited x-ray sensitivity of a direct conversion pixellated x-ray detector operating in the presence of deep trapping of charge carriers is calculated using the Shockley-Ramo theorem and the weighting potential of the individual pixel. The sensitivity of a pixellated x-ray detector is analyzed in terms of normalized parameters; (a) the normalized x-ray absorption depth (absorption depth/photoconductor thickness), (b) normalized pixel width (pixel size/thickness), and (c) normalized carrier schubwegs (schubweg/thickness). The charge collection and absorption-limited sensitivity of pixellated x-ray detectors mainly depends on the transport properties (mobility and lifetime) of the charges that move towards the pixel electrodes and the extent of dependence increases with decreasing normalized pixel width. The x-ray sensitivity of smaller pixels may be higher or lower than that of larger pixels depending on the rate of electron and hole trapping and the bias polarity. The sensitivity of pixellated detectors can be improved by ensuring that the carrier with the higher mobility-lifetime product is drifted towards the pixel electrodes

Exact bidirectional X -wave solutions in fiber Bragg gratings

Science.gov (United States)

Efremidis, Nikolaos K.; Nye, Nicholas S.; Christodoulides, Demetrios N.

2017-10-01

We find exact solutions describing bidirectional pulses propagating in fiber Bragg gratings. They are derived by solving the coupled-mode theory equations and are expressed in terms of products of modified Bessel functions with algebraic functions. Depending on the values of the two free parameters, the general bidirectional X -wave solution can also take the form of a unidirectional pulse. We analyze the symmetries and the asymptotic properties of the solutions and also discuss additional waveforms that are obtained by interference of more than one solution. Depending on their parameters, such pulses can create a sharp focus with high contrast.

X-ray interferometers

International Nuclear Information System (INIS)

Franks, A.

1980-01-01

An improved type of amplitude-division x-ray interferometer is described. The wavelength at which the interferometer can operate is variable, allowing the instrument to be used to measure x-ray wavelength, and the angle of inclination is variable for sample investigation. (U.K.)

The Cosmic History of Black Hole Accretion from Chandra X-ray Stacking

Science.gov (United States)

Treister, Ezequiel; Urry, C.; Schawinski, K.; Lee, N.; Natarajan, P.; Volonteri, M.; Sanders, D. B.

2012-05-01

In order to fully understand galaxy formation we need to know when in the cosmic history are black holes growing more intensively, in what type of galaxies this growth is happening and what fraction of these sources are invisible at most wavelengths due to obscuration. We take advantage of the rich multi-wavelength data available in the Chandra Deep Field South (CDF-S), including the 4 Msec Chandra observations (the deepest X-ray data to date), in order to measure the amount of black hole accretion as a function of cosmic history, from z 0 to z 6. We obtain stacked rest-frame X-ray spectra for samples of galaxies binned in terms of their IR luminosity, stellar mass and other galaxy properties. We find that the AGN fraction and their typical luminosities, and thus black hole accretion rates, increase with IR luminosity and stellar mass. The integrated intensity at high energies indicates that a significant fraction of the total black hole growth, 22%, occurs in heavily-obscured systems that are not individually detected in even the deepest X-ray observations. We find evidence for a strong connection between significant black hole growth events and major galaxy mergers from z 0 to z 3, while less spectacular but longer accretion episodes are most likely due to other (stochastic) processes. E.T. and K.S. gratefully acknowledges the support provided by NASA through Chandra Postdoctoral Fellowship Award Numbers PF8-90055 and PF9-00069, respectively issued by the Chandra X-ray Observatory Center. E.T. also thanks support by NASA through Chandra Award SP1-12005X Center of Excellence in Astrophysics and Associated Technologies (PFB 06). C. M. Urry acknowledges support from NSF Grants AST-0407295, AST-0449678, AST-0807570, and Yale University.

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