Diamond Light Source: status and perspectives.

PubMed

Materlik, Gerhard; Rayment, Trevor; Stuart, David I

2015-03-06

Diamond Light Source, a third-generation synchrotron radiation (SR) facility in the UK, celebrated its 10th anniversary in 2012. A private limited company was set up in April 2002 to plan, construct and operate the new user-oriented SR facility, called in brief Diamond. It succeeded the Synchrotron Radiation Source in Daresbury, a second-generation synchrotron that opened in 1980 as the world's first dedicated X-ray-providing facility, closing finally in 2008, by which time Diamond's accelerators and first beamlines were operating and user experiments were under way. This theme issue of Philosophical Transactions of the Royal Society A gives some examples of the rich diversity of research done in the initial five years, with some glimpses of activity up to 2014. Speakers at the 10 year anniversary symposium were drawn from a small number of major thematic areas and each theme was elaborated by a few speakers whose contributions were placed into a broader context by a leading member of the UK academic community in the role of rapporteur. This introduction gives a summary of the design choices and strategic planning of Diamond as a coherent user facility, a snapshot of its present status and some consideration of future perspectives. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

X-ray grating interferometer for materials-science imaging at a low-coherent wiggler source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herzen, Julia; Physics Department and Institute for Medical Engineering, Technische Universitaet Muenchen, 85748 Garching; Donath, Tilman

2011-11-15

X-ray phase-contrast radiography and tomography enable to increase contrast for weakly absorbing materials. Recently, x-ray grating interferometers were developed that extend the possibility of phase-contrast imaging from highly brilliant radiation sources like third-generation synchrotron sources to non-coherent conventional x-ray tube sources. Here, we present the first installation of a three grating x-ray interferometer at a low-coherence wiggler source at the beamline W2 (HARWI II) operated by the Helmholtz-Zentrum Geesthacht at the second-generation synchrotron storage ring DORIS (DESY, Hamburg, Germany). Using this type of the wiggler insertion device with a millimeter-sized source allows monochromatic phase-contrast imaging of centimeter sized objects withmore » high photon flux. Thus, biological and materials-science imaging applications can highly profit from this imaging modality. The specially designed grating interferometer currently works in the photon energy range from 22 to 30 keV, and the range will be increased by using adapted x-ray optical gratings. Our results of an energy-dependent visibility measurement in comparison to corresponding simulations demonstrate the performance of the new setup.« less

Pump–probe spectrometer for measuring x-ray induced strain

DOE PAGES

Loether, A.; Adams, B. W.; DiCharia, A.; ...

2016-04-20

A hard x-ray pump–probe spectrometer using a multi-crystal Bragg reflector is demonstrated at a third generation synchrotron source. This device derives both broadband pump and monochromatic probe pulses directly from a single intense, broadband x-ray pulse centered at 8.767 keV. In conclusion, we present a proof-of-concept experiment which directly measures x-ray induced crystalline lattice strain.

The penta-prism LTP: A long-trace-profiler with stationary optical head and moving penta prism (abstract)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qian, S.; Jark, W.; Takacs, P.Z.

1995-02-01

Metrology requirements for optical components for third generation synchrotron sources are taxing the state-of-the-art in manufacturing technology. We have investigated a number of effect sources in a commercial figure measurement instrument, the Long Trace Profiler II (LTP II), and have demonstrated that, with some simple modifications, we can significantly reduce the effect of error sources and improve the accuracy and reliability of the measurement. By keeping the optical head stationary and moving a penta prism along the translation stage, the stability of the optical system is greatly improved, and the remaining error signals can be corrected by a simple referencemore » beam subtraction. We illustrate the performance of the modified system by investigating the distortion produced by gravity on a typical synchrotron mirror and demonstrate the repeatability of the instrument despite relaxed tolerances on the translation stage.« less

The penta-prism LTP: A long-trace-profiler with stationary optical head and moving penta prism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qian, S.; Jark, W.; Takacs, P.Z.

1995-03-01

Metrology requirements for optical components for third-generation synchrotron sources are taxing the state of the art in manufacturing technology. We have investigated a number of error sources in a commercial figure measurement instrument, the Long-Trace-Profiler II, and have demonstrated that, with some simple modifications, we can significantly reduce the effect of error sources and improve the accuracy and reliability of the measurement. By keeping the optical head stationary and moving a penta prism along the translation stage, as in the original pencil-beam interferometer design of von Bieren, the stability of the optical system is greatly improved, and the remaining errormore » signals can be corrected by a simple reference beam subtraction. We illustrate the performance of the modified system by investigating the distortion produced by gravity on a typical synchrotron mirror and demonstrate the repeatability of the instrument despite relaxed tolerances on the translation stage.« less

Advanced Structural Analyses by Third Generation Synchrotron Radiation Powder Diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakata, M.; Aoyagi, S.; Ogura, T.

2007-01-19

Since the advent of the 3rd generation Synchrotron Radiation (SR) sources, such as SPring-8, the capabilities of SR powder diffraction increased greatly not only in an accurate structure refinement but also ab initio structure determination. In this study, advanced structural analyses by 3rd generation SR powder diffraction based on the Large Debye-Scherrer camera installed at BL02B2, SPring-8 is described. Because of high angular resolution and high counting statistics powder data collected at BL02B2, SPring-8, ab initio structure determination can cope with a molecular crystals with 65 atoms including H atoms. For the structure refinements, it is found that a kindmore » of Maximum Entropy Method in which several atoms are omitted in phase calculation become very important to refine structural details of fairy large molecule in a crystal. It should be emphasized that until the unknown structure is refined very precisely, the obtained structure by Genetic Algorithm (GA) or some other ab initio structure determination method using real space structural knowledge, it is not possible to tell whether the structure obtained by the method is correct or not. In order to determine and/or refine crystal structure of rather complicated molecules, we cannot overemphasize the importance of the 3rd generation SR sources.« less

Specific chemical and structural damage to proteins produced by synchrotron radiation.

PubMed

Weik, M; Ravelli, R B; Kryger, G; McSweeney, S; Raves, M L; Harel, M; Gros, P; Silman, I; Kroon, J; Sussman, J L

2000-01-18

Radiation damage is an inherent problem in x-ray crystallography. It usually is presumed to be nonspecific and manifested as a gradual decay in the overall quality of data obtained for a given crystal as data collection proceeds. Based on third-generation synchrotron x-ray data, collected at cryogenic temperatures, we show for the enzymes Torpedo californica acetylcholinesterase and hen egg white lysozyme that synchrotron radiation also can cause highly specific damage. Disulfide bridges break, and carboxyl groups of acidic residues lose their definition. Highly exposed carboxyls, and those in the active site of both enzymes, appear particularly susceptible. The catalytic triad residue, His-440, in acetylcholinesterase, also appears to be much more sensitive to radiation damage than other histidine residues. Our findings have direct practical implications for routine x-ray data collection at high-energy synchrotron sources. Furthermore, they provide a direct approach for studying the radiation chemistry of proteins and nucleic acids at a detailed, structural level and also may yield information concerning putative "weak links" in a given biological macromolecule, which may be of structural and functional significance.

Gas gun shock experiments with single-pulse x-ray phase contrast imaging and diffraction at the Advanced Photon Source

NASA Astrophysics Data System (ADS)

Luo, S. N.; Jensen, B. J.; Hooks, D. E.; Fezzaa, K.; Ramos, K. J.; Yeager, J. D.; Kwiatkowski, K.; Shimada, T.

2012-07-01

The highly transient nature of shock loading and pronounced microstructure effects on dynamic materials response call for in situ, temporally and spatially resolved, x-ray-based diagnostics. Third-generation synchrotron x-ray sources are advantageous for x-ray phase contrast imaging (PCI) and diffraction under dynamic loading, due to their high photon fluxes, high coherency, and high pulse repetition rates. The feasibility of bulk-scale gas gun shock experiments with dynamic x-ray PCI and diffraction measurements was investigated at the beamline 32ID-B of the Advanced Photon Source. The x-ray beam characteristics, experimental setup, x-ray diagnostics, and static and dynamic test results are described. We demonstrate ultrafast, multiframe, single-pulse PCI measurements with unprecedented temporal (<100 ps) and spatial (˜2 μm) resolutions for bulk-scale shock experiments, as well as single-pulse dynamic Laue diffraction. The results not only substantiate the potential of synchrotron-based experiments for addressing a variety of shock physics problems, but also allow us to identify the technical challenges related to image detection, x-ray source, and dynamic loading.

Soft-tissue and phase-contrast imaging at the Swiss Light Source

NASA Astrophysics Data System (ADS)

Schneider, Philipp; Mohan, Nishant; Stampanoni, Marco; Muller, Ralph

2004-05-01

Recent results show that bone vasculature is a major contributor to local tissue porosity, and therefore can be directly linked to the mechanical properties of bone tissue. With the advent of third generation synchrotron radiation (SR) sources, micro-computed tomography (μCT) with resolutions in the order of 1 μm and better has become feasible. This technique has been employed frequently to analyze trabecular architecture and local bone tissue properties, i.e. the hard or mineralized bone tissue. Nevertheless, less is known about the soft tissues in bone, mainly due to inadequate imaging capabilities. Here, we discuss three different methods and applications to visualize soft tissues. The first approach is referred to as negative imaging. In this case the material around the soft tissue provides the absorption contrast necessary for X-ray based tomography. Bone vasculature from two different mouse strains was investigated and compared qualitatively. Differences were observed in terms of local vessel number and vessel orientation. The second technique represents corrosion casting, which is principally adapted for imaging of vascular systems. The technique of corrosion casting has already been applied successfully at the Swiss Light Source. Using the technology we were able to show that pathological features reminiscent of Alzheimer"s disease could be distinguished in the brain vasculature of APP transgenic mice. The third technique discussed here is phase contrast imaging exploiting the high degree of coherence of third generation synchrotron light sources, which provide the necessary physical conditions for phase contrast. The in-line approach followed here for phase contrast retrieval is a modification of the Gerchberg-Saxton-Fienup type. Several measurements and theoretical thoughts concerning phase contrast imaging are presented, including mathematical phase retrieval. Although up-to-now only phase images have been computed, the approach is now ready to retrieve the phase for a large number of angular positions of the specimen allowing application of holotomography, which is the three-dimensional reconstruction of phase images.

Workshop on detectors for third-generation synchrotron sources: Proceedings

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1994-12-01

The aims of the workshop were (1) to acquaint APS users with current R and D being carried out on detectors, (2) to identify new detector systems possible during the next five years, (3) to identify new detectors theoretically possible in the future, (4) to stimulate interactions between user groups and detector developers, and (5) to obtain recommendations from expert panels on technical issues needing resolution. Development of detectors at ESRF, Spring-8, BNL, CERN and LBL are included.

Secure web book to store structural genomics research data.

PubMed

Manjasetty, Babu A; Höppner, Klaus; Mueller, Uwe; Heinemann, Udo

2003-01-01

Recently established collaborative structural genomics programs aim at significantly accelerating the crystal structure analysis of proteins. These large-scale projects require efficient data management systems to ensure seamless collaboration between different groups of scientists working towards the same goal. Within the Berlin-based Protein Structure Factory, the synchrotron X-ray data collection and the subsequent crystal structure analysis tasks are located at BESSY, a third-generation synchrotron source. To organize file-based communication and data transfer at the BESSY site of the Protein Structure Factory, we have developed the web-based BCLIMS, the BESSY Crystallography Laboratory Information Management System. BCLIMS is a relational data management system which is powered by MySQL as the database engine and Apache HTTP as the web server. The database interface routines are written in Python programing language. The software is freely available to academic users. Here we describe the storage, retrieval and manipulation of laboratory information, mainly pertaining to the synchrotron X-ray diffraction experiments and the subsequent protein structure analysis, using BCLIMS.

SESAME -- A third generation synchrotron light source for the Middle East

NASA Astrophysics Data System (ADS)

Winick, Herman

2012-03-01

Developed under the auspices of UNESCO and modeled on CERN, SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is an international research centre in construction in Jordan, enabling world-class research while promoting peace through scientific cooperation. Its centerpiece, a new 2.5 GeV 3rd Generation Electron Storage Ring (133m circumference, 26nm-rad emittance, 12 places for insertion devices), will provide intense light from infra-red to hard X-rays. Members of the Council (Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, Palestinian Authority,Turkey) provide the operations budget. Voluntary contributions by several Council Members that could amount to over 20 million over 5 years are now being finalized. This, plus funds from other sources, will enable acquisition of the technical components of the new ring and the upgrading of beamline equipment donated by several European and US labs. All concrete shielding is complete. The 0.8 GeV BESSY I injector system, a gift from Germany, is now being installed. A training program has been underway since 2000. SESAME is on track to start operation with four day-one beam lines in 2015.

Surface Structure as a Foundation of Nanotechnology

NASA Astrophysics Data System (ADS)

Robinson, Ian

2007-03-01

The three generations of synchrotron sources achieved to date, parasitic, dedicated and undulator-based, have each time revolutionized the field of X-ray diffraction. Surface structure determination, demonstrated (but very difficult) already with Coolidge tube sources, benefited from the enormous flux gain in the first generation, such as SSRL. Dedicated 2nd-generation sources, such as NSLS, allowed in-situ surface preparation and reliable steady beams to be available when a surface was ready to measure. Third generation sources, such as APS, enormously improved the brightness, hence coherence, and thus allowed access to the surfaces of nanoparticles. This talk will illustrate how these technological advances led to two significant scientific breakthroughs. The concept of crystal truncation rods (CTR) led to new views of how the surface is a modification of, but still an extension of the bulk crystal structure. The development of lensless coherent x-ray diffraction (CXD) imaging has allowed access to the structure of nanocrystalline materials by three-dimensional phase mapping of the particle interiors. The structural principles of these new nano materials are being investigated at present using these new methods.

Experimental setup for the study of resonant inelastic X-ray scattering of organometallic complexes in gas phase

NASA Astrophysics Data System (ADS)

Ismail, I.; Guillemin, R.; Marchenko, T.; Travnikova, O.; Ablett, J. M.; Rueff, J.-P.; Piancastelli, M.-N.; Simon, M.; Journel, L.

2018-06-01

A new setup has been designed and built to study organometallic complexes in gas phase at the third-generation Synchrotron radiation sources. This setup consists of a new homemade computer-controlled gas cell that allows us to sublimate solid samples by accurately controlling the temperature. This cell has been developed to be a part of the high-resolution X-ray emission spectrometer permanently installed at the GALAXIES beamline of the French National Synchrotron Facility SOLEIL. To illustrate the capabilities of the setup, the cell has been successfully used to record high-resolution Kα emission spectra of gas-phase ferrocene F e (C5H5) 2 and to characterize their dependence with the excitation energy. This will allow to extend resonant X-ray emission to different organometallic molecules.

Short x-ray pulse generation using deflecting cavities at the Advanced Photon Source.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sajaev, V.; Borland, M.; Chae, Y.-C.

2007-11-11

Storage-ring-based third-generation light sources can provide intense radiation pulses with durations as short as 100 ps. However, there is growing interest within the synchrotron radiation user community in performing experiments with much shorter X-ray pulses. Zholents et al. [Nucl. Instr. and Meth. A 425 (1999) 385] recently proposed using RF orbit deflection to generate sub-ps X-ray pulses. In this scheme, two deflecting cavities are used to deliver a longitudinally dependent vertical kick to the beam. An optical slit can then be used to slice out a short part of the radiation pulse. Implementation of this scheme is planned for onemore » APS beamline in the near future. In this paper, we summarize our feasibility study of this method and the expected X-ray beam parameters. We find that a pulse length of less than two picoseconds can be achieved.« less

Development of an X-ray imaging system to prevent scintillator degradation for white synchrotron radiation.

PubMed

Zhou, Tunhe; Wang, Hongchang; Connolley, Thomas; Scott, Steward; Baker, Nick; Sawhney, Kawal

2018-05-01

The high flux of the white X-ray beams from third-generation synchrotron light sources can significantly benefit the development of high-speed X-ray imaging, but can also bring technical challenges to existing X-ray imaging systems. One prevalent problem is that the image quality deteriorates because of dust particles accumulating on the scintillator screen during exposure to intense X-ray radiation. Here, this problem has been solved by embedding the scintillator in a flowing inert-gas environment. It is also shown that the detector maintains the quality of the captured images even after days of X-ray exposure. This modification is cost-efficient and easy to implement. Representative examples of applications using the X-ray imaging system are also provided, including fast tomography and multimodal phase-contrast imaging for biomedical and geological samples. open access.

Development of an X-ray imaging system to prevent scintillator degradation for white synchrotron radiation

PubMed Central

Zhou, Tunhe; Wang, Hongchang; Scott, Steward

2018-01-01

The high flux of the white X-ray beams from third-generation synchrotron light sources can significantly benefit the development of high-speed X-ray imaging, but can also bring technical challenges to existing X-ray imaging systems. One prevalent problem is that the image quality deteriorates because of dust particles accumulating on the scintillator screen during exposure to intense X-ray radiation. Here, this problem has been solved by embedding the scintillator in a flowing inert-gas environment. It is also shown that the detector maintains the quality of the captured images even after days of X-ray exposure. This modification is cost-efficient and easy to implement. Representative examples of applications using the X-ray imaging system are also provided, including fast tomography and multimodal phase-contrast imaging for biomedical and geological samples. PMID:29714191

Third user workshop on high-power lasers at the Linac Coherent Light Source

DOE PAGES

Bolme, Cynthia Anne; Glenzer, Sigfried; Fry, Alan

2016-03-24

On October 5–6, 2015, the third international user workshop focusing on high-power lasers at the Linac Coherent Light Source (LCLS) was held in Menlo Park, CA, USA [1 R. Falcone, S. Glenzer, and S. Hau-Riege, Synchrotron Radiation News 27(2), 56–58 (2014)., 2 P. Heimann and S. Glenzer, Synchrotron Radiation News 28(3), 54–56 (2015).]. Here, the workshop was co-organized by Los Alamos National Laboratory and SLAC National Accelerator Laboratory. More than 110 scientists attended from North America, Europe, and Asia to discuss high-energy-density (HED) science that is enabled by the unique combination of high-power lasers with the LCLS X-rays at themore » LCLS-Matter in Extreme Conditions (MEC) endstation.« less

Frontiers of X-ray research at the Advanced Photon Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dehmer, J.J.

1995-12-31

With providential timing, the Advanced Photon Source (APS) at Argonne National Laboratory has begun to produce x-rays during the centennial year of Wilhelm Rongtgen`s discovery of a {open_quotes}new kind of rays.{close_quotes} When complete, this third-generation, 7-GeV positron storage ring will produce nearly one hundred intense x-ray beams, with a major emphasis on the laser-like (highly collimated, locally coherent) beams from undulator sources. This talk will provide an overview of (1) the important properties of the synchrotron radiation to be produced by the APS, (2) the major classes of experimental approaches that use x-rays, and (3) some speculation on the impactsmore » of the APS on the materials, chemical, biological, and environmental sciences.« less

Quantitative performance measurements of bent crystal Laue analyzers for X-ray fluorescence spectroscopy.

PubMed

Karanfil, C; Bunker, G; Newville, M; Segre, C U; Chapman, D

2012-05-01

Third-generation synchrotron radiation sources pose difficult challenges for energy-dispersive detectors for XAFS because of their count rate limitations. One solution to this problem is the bent crystal Laue analyzer (BCLA), which removes most of the undesired scatter and fluorescence before it reaches the detector, effectively eliminating detector saturation due to background. In this paper experimental measurements of BCLA performance in conjunction with a 13-element germanium detector, and a quantitative analysis of the signal-to-noise improvement of BCLAs are presented. The performance of BCLAs are compared with filters and slits.

Basic design of a multi wire proportional counter using Garfield++ for ILSF

NASA Astrophysics Data System (ADS)

Ghahremani Gol, M.; Ashrafi, S.; Rahighi, J.

2016-12-01

The Iranian Light Source Facility (ILSF) is a new 3 GeV third generation synchrotron radiation facility in Middle East, which at the time being is in its design stage. An important aspect for the scientific success of this new source will be the availability of well adapted detectors. Position-sensitive X-ray detectors have played an important role in synchrotron radiation X-ray experiments for many years and are still in use. An operational one-dimensional multiwire position sensitive detector with delay line readout produced by ILSF showed a position resolution of 230 μm. In this paper, we introduce a 2-D position sensitive gas detector based on a multiwire proportional chamber which will be used in small/wide angle scattering and diffraction experiments with synchrotron radiation at the ILSF. The parameters of its components, including the gas filling, gas pressure, temperature, the geometry of anode and cathodes planes as well as the expected performance of the designed system will be described in the following. For the design and the simulation of MWPC the Elmer and Garfield++ codes have been employed. We have built and tested a MWPC as a prototype at ILSF. The results obtained so far show a good position sensing. After primary test the detector has been optimized and is now ready for test at Elettra.

A compact dispersive refocusing Rowland circle X-ray emission spectrometer for laboratory, synchrotron, and XFEL applications

DOE PAGES

Holden, William M.; Hoidn, Oliver R.; Ditter, Alexander S.; ...

2017-07-27

X-ray emission spectroscopy is emerging as an important complement to x-ray absorption fine structure spectroscopy, providing a characterization of the occupied electronic density of states local to the species of interest. Here, we present details of the design and performance of a compact x-ray emission spectrometer that uses a dispersive refocusing Rowland (DRR) circle geometry to achieve excellent performance for the 2-2.5 keV range, i.e., especially for the K-edge emission from sulfur and phosphorous. The DRR approach allows high energy resolution even for unfocused x-ray sources. This property enables high count rates in laboratory studies, approaching those of insertion-device beamlinesmore » at third-generation synchrotrons, despite use of only a low-powered, conventional x-ray tube. The spectrometer, whose overall scale is set by use of a 10-cm diameter Rowland circle and a new small-pixel complementary metal-oxide-semiconductor x-ray camera, is easily portable to synchrotron or x-ray free electron laser beamlines. Photometrics from measurements at the Advanced Light Source show excellent overall instrumental efficiency. In addition, the compact size of this instrument lends itself to future multiplexing to gain large factors in net collection efficiency or its implementation in controlled gas gloveboxes either in the lab or in an endstation.« less

PREFACE Preface

NASA Astrophysics Data System (ADS)

Sakurai, Kazuo; Takahara, Atsushi

2011-01-01

This special issue contains peer-reviewed invited and contributed papers that were presented at The International Symposium on 'Future Trend in Soft Material Research with Advanced Light Source: Interdisciplinary of Bio- & Synthetic- Materials and Industrial Transferring', which was held in SPring-8, Japan, on September 1-3, 2010. Advanced light sources including neutron and synchrotron are becoming increasingly critical to the study of soft materials. This cutting-edge analytical tool is expected to lead to the creation of new materials with revolutionary properties and functions. At SPring-8, a new beam line dedicated to soft materials has now been launched as one of the most powerful X-rays for scattering and diffraction. Additionally, the next-generation light source, XFEL (X-ray Free Electron Laser), facilities are currently being developed in several locations. In the near future, femto-second and coherent X-ray sources will be available in soft material research and should reveal the various new aspects of advanced soft material research and technology. On the occasion of the third fiscal year of the CREST (project leader: Kazuo Sakurai) and ERATO (project leader: Atsushi Takahara) projects, we organized this international symposium in order to accelerate the discussion among global-level researchers working on next-generation synchrotron radiation science, biophysics and supramolecular science, modern surface science in soft materials, and industrial applications of neutron and synchrotron radiation sources. In this symposium 21 oral presentations, including 8 invited speakers from abroad, and 40 poster presentations from USA, France, Korea, Taiwan, and Japan were presented during the three day symposium. The symposium chairs reviewed the poster presentations by young scientists, and eight young researchers received the Award for Best Poster Presentation. We sincerely hope that these proceedings will be beneficial in future applications of advanced light sources to soft materials science and technology, not only to our ERATO and CREST projects, but also to the research of all the participants, broadening our scientific horizons. Kazuo Sakurai & Atsushi TakaharaSymposium Chairs Symposium Organization and Committee Supported by: Japan Science and Technology Agency (JST) Japan Synchrotron Radiation Research Institute (JASRI) Co-sponsored by: Society of Japan Polymer Science Japanese Society of Synchrotron Radiation Research Advanced Softmaterial Beamline Consortium Symposium Chairs: Atsushi Takahara (Kyushu University, JST, ERATO) Kazuo Sakurai (Univ. Kitakyushu, JST, CREST) Organizing Committee: Yoshiyuki Amemiya (The Univ. of Tokyo, JST, CREST) Naoto Yagi (JASRI, JST, CREST) Masaki Takata (JASRI) Isamu Akiba (Univ. Kitakyushu, JST, CREST) Yuya Shinohara (The Univ. of Tokyo, JST, CREST) Taiki Hoshino (Kyushu University, JST, ERATO) Jun-ichi Imuta (Kyushu University, JST, ERATO) Moriya Kikuchi (Kyushu University, JST, ERATO) Motoyasu Kobayashi (Kyushu University, JST, ERATO) Group photograph Group photograph Lecture meeting Lecture meeting

Results from the RF BPM Upgrade Prototype at the Advanced Photon Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pietryla, Anthony; Lill, Robert; Norum, Eric

2006-11-20

The Advanced Photon Source (APS), a third-generation synchrotron light source, has been in operation for 10 years. The monopulse radio frequency (RF) beam position monitor (BPM) is one of three BPM types now employed in the storage ring at the APS. It is a broadband (10 MHz) system designed to measure single-turn and multi-turn beam positions, but it suffers from an aging data acquisition system. The replacement BPM system retains the existing monopulse receivers and replaces the data acquisition system with high-speed analog-to-digital converters (ADCs) and a field programmable gate array (FPGA) that performs the signal processing. A prototype systemmore » was constructed and is currently being evaluated. This paper presents the results obtained from laboratory and field tests of the prototype system.« less

Results from the RF BPM upgrade prototype at the Advanced Photon Source.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pietryla, A.; Lill, R.; Norum, E.

2006-01-01

The Advanced Photon Source (APS), a third-generation synchrotron light source, has been in operation for 10 years. The monopulse radio frequency (RF) beam position monitor (BPM) is one of three BPM types now employed in the storage ring at the APS. It is a broadband (10 MHz) system designed to measure single-turn and multi-turn beam positions, but it suffers from an aging data acquisition system. The replacement BPM system retains the existing monopulse receivers and replaces the data acquisition system with high-speed analog-to-digital converters (ADCs) and a field programmable gate array (FPGA) that performs the signal processing. A prototype systemmore » was constructed and is currently being evaluated. This paper presents the results obtained from laboratory and field tests of the prototype system.« less

Picosecond, tunable, high-brightness hard x-ray inverse Compton source at Duke storage ring

NASA Astrophysics Data System (ADS)

Litvinenko, Vladimir N.; Wu, Ying; Burnham, Bentley; Barnett, Genevieve A.; Madey, John M. J.

1995-09-01

We suggest a state-of-the art x-ray source using a compact electron storage ring with modest energy (less than 1 GeV) and a high power mm-wave as an undulator. A source of this type has x-ray energies and brightness comparable with third generation synchrotron light sources while it can be very compact and fit in a small university or industrial laboratory or hospital. We propose to operate an isochronous mm-wave FEL and a hard x-ray inverse Compton source at the Duke storage ring to test this concept. Resonant FEL conditions for the mm- wave will be provided by the off-axis interaction with an electromagnetic wave. A special optical resonator with holes for the e-beam is proposed for pumping a hard x-ray inverse Compton source with very high brightness. Simulation results of mm-wave FEL operation of the Duke storage ring are discussed. Expected performance of mm-wave FEL and hard x-ray inverse Compton source are presented.

WavePropaGator: interactive framework for X-ray free-electron laser optics design and simulations.

PubMed

Samoylova, Liubov; Buzmakov, Alexey; Chubar, Oleg; Sinn, Harald

2016-08-01

This article describes the WavePropaGator ( WPG ) package, a new interactive software framework for coherent and partially coherent X-ray wavefront propagation simulations. The package has been developed at European XFEL for users at the existing and emerging free-electron laser (FEL) facilities, as well as at the third-generation synchrotron sources and future diffraction-limited storage rings. The WPG addresses the needs of beamline scientists and user groups to facilitate the design, optimization and improvement of X-ray optics to meet their experimental requirements. The package uses the Synchrotron Radiation Workshop ( SRW ) C/C++ library and its Python binding for numerical wavefront propagation simulations. The framework runs reliably under Linux, Microsoft Windows 7 and Apple Mac OS X and is distributed under an open-source license. The available tools allow for varying source parameters and optics layouts and visualizing the results interactively. The wavefront history structure can be used for tracking changes in every particular wavefront during propagation. The batch propagation mode enables processing of multiple wavefronts in workflow mode. The paper presents a general description of the package and gives some recent application examples, including modeling of full X-ray FEL beamlines and start-to-end simulation of experiments.

High-resolution x-ray imaging for microbiology at the Advanced Photon Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lai, B.; Kemner, K. M.; Maser, J.

1999-11-02

Exciting new applications of high-resolution x-ray imaging have emerged recently due to major advances in high-brilliance synchrotrons sources and high-performance zone plate optics. Imaging with submicron resolution is now routine with hard x-rays: the authors have demonstrated 150 run in the 6--10 keV range with x-ray microscopes at the Advanced Photon Source (APS), a third-generation synchrotrons radiation facility. This has fueled interest in using x-ray imaging in applications ranging from the biomedical, environmental, and materials science fields to the microelectronics industry. One important application they have pursued at the APS is a study of the microbiology of bacteria and theirmore » associated extracellular material (biofilms) using fluorescence microanalysis. No microscopy techniques were previously available with sufficient resolution to study live bacteria ({approx}1 {micro}m x 4 {micro}m in size) and biofilms in their natural hydrated state with better than part-per-million elemental sensitivity and the capability of determining g chemical speciation. In vivo x-ray imaging minimizes artifacts due to sample fixation, drying, and staining. This provides key insights into the transport of metal contaminants by bacteria in the environment and potential new designs for remediation and sequestration strategies.« less

Next-generation materials for future synchrotron and free-electron laser sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Assoufid, Lahsen; Graafsma, Heinz

We show that the development of new materials and improvements of existing ones are at the root of the spectacular recent developments of new technologies for synchrotron storage rings and free-electron laser sources. This holds true for all relevant application areas, from electron guns to undulators, x-ray optics, and detectors. As demand grows for more powerful and efficient light sources, efficient optics, and high-speed detectors, an overview of ongoing materials research for these applications is timely. In this article, we focus on the most exciting and demanding areas of materials research and development for synchrotron radiation optics and detectors. Materialsmore » issues of components for synchrotron and free-electron laser accelerators are briefly discussed. Lastly, the articles in this issue expand on these topics.« less

Next-generation materials for future synchrotron and free-electron laser sources

DOE PAGES

Assoufid, Lahsen; Graafsma, Heinz

2017-06-09

We show that the development of new materials and improvements of existing ones are at the root of the spectacular recent developments of new technologies for synchrotron storage rings and free-electron laser sources. This holds true for all relevant application areas, from electron guns to undulators, x-ray optics, and detectors. As demand grows for more powerful and efficient light sources, efficient optics, and high-speed detectors, an overview of ongoing materials research for these applications is timely. In this article, we focus on the most exciting and demanding areas of materials research and development for synchrotron radiation optics and detectors. Materialsmore » issues of components for synchrotron and free-electron laser accelerators are briefly discussed. Lastly, the articles in this issue expand on these topics.« less

The contribution of synchrotron X-ray computed microtomography to understanding volcanic processes.

PubMed

Polacci, Margherita; Mancini, Lucia; Baker, Don R

2010-03-01

A series of computed microtomography experiments are reported which were performed by using a third-generation synchrotron radiation source on volcanic rocks from various active hazardous volcanoes in Italy and other volcanic areas in the world. The applied technique allowed the internal structure of the investigated material to be accurately imaged at the micrometre scale and three-dimensional views of the investigated samples to be produced as well as three-dimensional quantitative measurements of textural features. The geometry of the vesicle (gas-filled void) network in volcanic products of both basaltic and trachytic compositions were particularly focused on, as vesicle textures are directly linked to the dynamics of volcano degassing. This investigation provided novel insights into modes of gas exsolution, transport and loss in magmas that were not recognized in previous studies using solely conventional two-dimensional imaging techniques. The results of this study are important to understanding the behaviour of volcanoes and can be combined with other geosciences disciplines to forecast their future activity.

Perspectives of synchrotron radiation sources with superconductivity

NASA Astrophysics Data System (ADS)

Tanaka, Takashi

2007-10-01

The synchrotron radiation source is a magnetic device to generate a periodic magnetic field where a relativistic electron moves along a periodic trajectory and emits light called synchrotron radiation (SR), which has been used as a scientific probe for many years in various fields. Although permanent magnets (PMs) are usually used to generate the magnetic field in the SR source because of their cost-effectiveness and availability, a large number of SR sources with superconductors have been constructed for special uses, i.e., to obtain a strong magnetic field over 3 T, which cannot be achieved by using PMs alone. Most of these SR sources are composed of electromagnets with superconducting coils made of NbTi as in commercially available superconducting magnets. For stronger magnetic field, research on application of Nb3Sn is in progress. On the other hand, utilization of high Tc superconducting bulk magnets has been recently proposed and R&Ds toward realization are being carried out. This paper reviews the currents status of the SR sources with superconductivity and describes the future perspectives.

Status of the RF BPM upgrade at the Advanced Photon Source.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pietryla, A.; Bui, H.; Decker, G.

2008-01-01

The Advanced Photon Source (APS),a third-generation synchrotron light source, has been in operation for eleven years. The monopulse radio frequency (rf) beam position monitor (BPM) is one of three BPM types now employed in the storage ring at the APS. It is a broadband (10 MHz) system designed to measure single-turn and multi-turn beam positions, but it suffers from an aging data acquisition system. The replacement BPM system retains the existing monopulse receivers and replaces the data acquisition system with high-speed analog-to-digital converters (ADCs) and a field-programmable gate array (FPGA) that performs the signal processing. A first-article system has beenmore » constructed and is currently being evaluated. This paper presents the results of testing of the first-article system as well as the progress made in other areas of this upgrade effort.« less

NSLS-II storage ring insertion device and front-end commissioning and operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, G., E-mail: gwang@bnl.gov; Shaftan, T.; Amundsen, C.

The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source at Brookhaven National Laboratory. During spring/ summer of 2014, the storage ring was commissioned up to 50 mA without insertion devices. In the fall of 2014, we began commissioning of the project beamlines, which included seven insertion devices on six ID ports. Beamlines IXS, HXN, CSX-1, CSX-2, CHX, SRX, and XPD-1 consist of elliptically polarized undulator (EPU), damping wigglers (DW) and in-vacuum undulators (IVU) covering from VUV to hard x-ray range. In this paper, experience with commissioning and operation is discussed.more » We focus on reaching storage ring performance with IDs, including injection, design emittance, compensation of orbit distortions caused by ID residual field, source point stability, beam alignment and tools for control, monitoring and protection of the ring chambers from ID radiation.« less

1994 Activity Report, National Synchrotron Light Source. Annual report, October 1, 1993-September 30, 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rothman, E.Z.

1995-05-01

This report is a summary of activities carried out at the National Synchrotron Light Source during 1994. It consists of sections which summarize the work carried out in differing scientific disciplines, meetings and workshops, operations experience of the facility, projects undertaken for upgrades, administrative reports, and collections of abstracts and publications generated from work done at the facility.

Deciphering complex, functional structures with synchrotron-based absorption and phase contrast tomographic microscopy

NASA Astrophysics Data System (ADS)

Stampanoni, M.; Reichold, J.; Weber, B.; Haberthür, D.; Schittny, J.; Eller, J.; Büchi, F. N.; Marone, F.

2010-09-01

Nowadays, thanks to the high brilliance available at modern, third generation synchrotron facilities and recent developments in detector technology, it is possible to record volumetric information at the micrometer scale within few minutes. High signal-to-noise ratio, quantitative information on very complex structures like the brain micro vessel architecture, lung airways or fuel cells can be obtained thanks to the combination of dedicated sample preparation protocols, in-situ acquisition schemes and cutting-edge imaging analysis instruments. In this work we report on recent experiments carried out at the TOMCAT beamline of the Swiss Light Source [1] where synchrotron-based tomographic microscopy has been successfully used to obtain fundamental information on preliminary models for cerebral fluid flow [2], to provide an accurate mesh for 3D finite-element simulation of the alveolar structure of the pulmonary acinus [3] and to investigate the complex functional mechanism of fuel cells [4]. Further, we introduce preliminary results on the combination of absorption and phase contrast microscopy for the visualization of high-Z nanoparticles in soft tissues, a fundamental information when designing modern drug delivery systems [5]. As an outlook we briefly discuss the new possibilities offered by high sensitivity, high resolution grating interferomtery as well as Zernike Phase contrast nanotomography [6].

Bragg-Fresnel optics: New field of applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snigirev, A.

Bragg-Fresnel Optics shows excellent compatibility with the third generation synchrotron radiation sources such as ESRF and is capable of obtaining monochromatic submicron focal spots with 10{sup 8}-10{sup 9} photons/sec in an energy bandwidth of 10{sup -4}-10{sup -6} and in a photon energy range between 2-100 keV. New types of Bragg-Fresnel lenses like modified, ion implanted, bent and acoustically modulated were tested. Microprobe techniques like microdiffraction and microfluorescence based on Bragg-Fresnel optics were realised at the ESRF beamlines. Excellent parameters of the X-ray beam at the ESRF in terms of low emittance and quite small angular source size allow for Bragg-Fresnelmore » optics to occupy new fields of applications such as high resolution diffraction, holography, interferometry and phase contrast imaging.« less

Attosecond light sources in the water window

NASA Astrophysics Data System (ADS)

Ren, Xiaoming; Li, Jie; Yin, Yanchun; Zhao, Kun; Chew, Andrew; Wang, Yang; Hu, Shuyuan; Cheng, Yan; Cunningham, Eric; Wu, Yi; Chini, Michael; Chang, Zenghu

2018-02-01

As a compact and burgeoning alternative to synchrotron radiation and free-electron lasers, high harmonic generation (HHG) has proven its superiority in static and time-resolved extreme ultraviolet spectroscopy for the past two decades and has recently gained many interests and successes in generating soft x-ray emissions covering the biologically important water window spectral region. Unlike synchrotron and free-electron sources, which suffer from relatively long pulse width or large time jitter, soft x-ray sources from HHG could offer attosecond time resolution and be synchronized with their driving field to investigate time-resolved near edge absorption spectroscopy, which could reveal rich structural and dynamical information of the interrogated samples. In this paper, we review recent progresses on generating and characterizing attosecond light sources in the water window region. We show our development of an energetic, two-cycle, carrier-envelope phase stable laser source at 1.7 μm and our achievement in producing a 53 as soft x-ray pulse covering the carbon K-edge in the water window. Such source paves the ways for the next generation x-ray spectroscopy with unprecedented temporal resolution.

Development of Partially-Coherent Wavefront Propagation Simulation Methods for 3rd and 4th Generation Synchrotron Radiation Sources.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chubar O.; Berman, L; Chu, Y.S.

2012-04-04

Partially-coherent wavefront propagation calculations have proven to be feasible and very beneficial in the design of beamlines for 3rd and 4th generation Synchrotron Radiation (SR) sources. These types of calculations use the framework of classical electrodynamics for the description, on the same accuracy level, of the emission by relativistic electrons moving in magnetic fields of accelerators, and the propagation of the emitted radiation wavefronts through beamline optical elements. This enables accurate prediction of performance characteristics for beamlines exploiting high SR brightness and/or high spectral flux. Detailed analysis of radiation degree of coherence, offered by the partially-coherent wavefront propagation method, ismore » of paramount importance for modern storage-ring based SR sources, which, thanks to extremely small sub-nanometer-level electron beam emittances, produce substantial portions of coherent flux in X-ray spectral range. We describe the general approach to partially-coherent SR wavefront propagation simulations and present examples of such simulations performed using 'Synchrotron Radiation Workshop' (SRW) code for the parameters of hard X-ray undulator based beamlines at the National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory. These examples illustrate general characteristics of partially-coherent undulator radiation beams in low-emittance SR sources, and demonstrate advantages of applying high-accuracy physical-optics simulations to the optimization and performance prediction of X-ray optical beamlines in these new sources.« less

Pure-type superconducting permanent-magnet undulator.

PubMed

Tanaka, Takashi; Tsuru, Rieko; Kitamura, Hideo

2005-07-01

A novel synchrotron radiation source is proposed that utilizes bulk-type high-temperature superconductors (HTSCs) as permanent magnets (PMs) by in situ magnetization. Arrays of HTSC blocks magnetized by external magnetic fields are placed below and above the electron path instead of conventional PMs, generating a periodic magnetic field with an offset. Two methods are presented to magnetize the HTSCs and eliminate the field offset, enabling the HTSC arrays to work as a synchrotron radiation source. An analytical formula to calculate the peak field achieved in a device based on this scheme is derived in a two-dimensional form for comparison with synchrotron radiation sources using conventional PMs. Experiments were performed to demonstrate the principle of the proposed scheme and the results have been found to be very promising.

Electron beam ion sources for use in second generation synchrotrons for medical particle therapy

NASA Astrophysics Data System (ADS)

Zschornack, G.; Ritter, E.; Schmidt, M.; Schwan, A.

2014-02-01

Cyclotrons and first generation synchrotrons are the commonly applied accelerators in medical particle therapy nowadays. Next generation accelerators such as Rapid Cycling Medical Synchrotrons (RCMS), direct drive accelerators, or dielectric wall accelerators have the potential to improve the existing accelerator techniques in this field. Innovative accelerator concepts for medical particle therapy can benefit from ion sources which meet their special requirements. In the present paper we report on measurements with a superconducting Electron Beam Ion Source, the Dresden EBIS-SC, under the aspect of application in combination with RCMS as a well proven technology. The measurements indicate that this ion source can offer significant advantages for medical particle therapy. We show that a superconducting EBIS can deliver ion pulses of medically relevant ions such as protons, C4 + and C6 + ions with intensities and frequencies required for RCMS [S. Peggs and T. Satogata, "A survey of Hadron therapy accelerator technology," in Proceedings of PAC07, BNL-79826- 2008-CP, Albuquerque, New Mexico, USA, 2007; A. Garonna, U. Amaldi et al., "Cyclinac medical accelerators using pulsed C6 +/H+_2 ion sources," in Proceedings of EBIST 2010, Stockholm, Sweden, July 2010]. Ion extraction spectra as well as individual ion pulses have been measured. For example, we report on the generation of proton pulses with up to 3 × 109 protons per pulse and with frequencies of up to 1000 Hz at electron beam currents of 600 mA.

Toward a fourth-generation x-ray source.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Monction, D. E.

1999-05-19

The field of synchrotron radiation research has grown rapidly over the last 25 years due to both the push of the accelerator and magnet technology that produces the x-ray beams and the pull of the extraordinary scientific research that is possible with them. Three successive generations of synchrotrons radiation facilities have resulted in beam brilliances 11 to 12 orders of magnitude greater than the standard laboratory x-ray tube. However, greater advances can be easily imagined given the fact that x-ray beams from present-day facilities do not exhibit the coherence or time structure so familiar with the optical laser. Theoretical workmore » over the last ten years or so has pointed to the possibility of generating hard x-ray beams with laser-like characteristics. The concept is based on self-amplified spontaneous emission (SASE) in flee-electron lasers. A major facility of this type based upon a superconducting linac could produce a cost-effective facility that spans wave-lengths from the ultraviolet to the hard x-ray regime, simultaneously servicing large numbers experimenters from a wide range of disciplines. As with each past generation of synchrotrons facilities, immense new scientific opportunities would result from fourth-generation sources.« less

Mechanisms of lichen resistance to metallic pollution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarret, C.; Manceau, A.; Eybert-Berard, L.

1998-11-01

Some lichens have a unique ability to grow in heavily contaminated areas due to the development of adaptative mechanisms allowing a high tolerance to metals. Here the authors report on the chemical forms of Pb and Zn in the metal hyperaccumulator Diploschistes muscorum and of Pb in the metal tolerant lichen Xanthoria parietina. The speciation of Zn and Pb has been investigated by powder X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) spectroscopy using the advanced third-generation synchrotron radiation source of the European synchrotron radiation facility (ESRF in Grenoble). This study reveals that in both lichens cells aremore » protected from toxicity by complexation of heavy metals, but the strategies differ: in D. muscorum, Pb and Zn are accumulated through an enhanced synthesis of oxalate, which precipitates toxic elements as insoluble salts, whereas in X. parietina, Pb is complexed to carboxylic groups of the fungal cell walls. The authors conclude that hyperaccumulation of metals results from a reactive mechanism of organic acid production, whereas metallo-tolerance is achieved by a passive complexation to existing functional groups.« less

High resolution microdiffraction studies using synchrotron radiation

NASA Astrophysics Data System (ADS)

Spolenak, R.; Tamura, N.; Valek, B. C.; MacDowell, A. A.; Celestre, R. S.; Padmore, H. A.; Brown, W. L.; Marieb, T.; Batterman, B. W.; Patel, J. R.

2002-04-01

The advent of third generation synchrotron light sources in combination with x-ray focusing devices such as Kirkpatrick-Baez mirrors make Laue diffraction on a submicron length scale possible. Analysis of Laue images enables us to determine the deviatoric part of the 3D strain tensor to an accuracy of 2×10-4 in strain with a spatial resolution comparable to the grain size in our thin films. In this paper the application of x-ray microdiffraction to the temperature dependence of the mechanical behavior of a sputtered blanket Cu film and of electroplated damascene Cu lines will be presented. Microdiffraction reveals very large variations in the strain of a film or line from grain to grain. When the strain is averaged over a macroscopic region the results are in good agreement with direct macroscopic stress measurements. However, the strain variations are so large that in some cases in which the average stress is tensile there are some grains actually under compression. The full implications of these observations are still being considered, but it is clear that the mechanical properties of thin film materials are now accessible with new visibility.

Two year operational experience with the TPS vacuum system

NASA Astrophysics Data System (ADS)

Yang, Y. C.; Chan, C. K.; Sheng, I. C.; Huang, I. T.; Y Chung, J.; Liang, C. C.

2017-07-01

The Taiwan Photon Source (TPS), a 3-GeV third generation synchrotron light source, was commissioned in 2014 December and is now currently operated in top-up mode at 300mA for users. During the past two years, the machine was completed to meet design goals with among others the installation of superconducting cavities (SRF), the installation of insertion devices (ID) and the correction of vacuum chamber structure downstream from the IDs. The design goal of 500mA beam current was achieved with a total accumulated beam dose of more than 1000Ah, resulting in three orders of magnitude reduction of out-gassing. As the beam current was increased, a few vacuum problems were encountered, including vacuum leaks, unexpected pressure bursts, etc. Vacuum related issues including high pressure events, lessons learned and operational experience will be presented and discussed in this paper.

Optical design and simulation of a new coherence beamline at NSLS-II

NASA Astrophysics Data System (ADS)

Williams, Garth J.; Chubar, Oleg; Berman, Lonny; Chu, Yong S.; Robinson, Ian K.

2017-08-01

We will discuss the optical design for a proposed beamline at NSLS-II, a late-third generation storage ring source, designed to exploit the spatial coherence of the X-rays to extract high-resolution spatial information from ordered and disordered materials through Coherent Diffractive Imaging, executed in the Bragg- and forward-scattering geometries. This technique offers a powerful tool to image sub-10 nm spatial features and, within ordered materials, sub-Angstrom mapping of deformation fields. Driven by the opportunity to apply CDI to a wide range of samples, with sizes ranging from sub-micron to tens-of-microns, two optical designs have been proposed and simulated under a wide variety of optical configurations using the software package Synchrotron Radiation Workshop. The designs, their goals, and the results of the simulation, including NSLS-II ring and undulator source parameters, of the beamline performance as a function of its variable optical components is described.

Submicron x-ray diffraction and its applications to problems in materials and environmental science

NASA Astrophysics Data System (ADS)

Tamura, N.; Celestre, R. S.; MacDowell, A. A.; Padmore, H. A.; Spolenak, R.; Valek, B. C.; Meier Chang, N.; Manceau, A.; Patel, J. R.

2002-03-01

The availability of high brilliance third generation synchrotron sources together with progress in achromatic focusing optics allows us to add submicron spatial resolution to the conventional century-old x-ray diffraction technique. The new capabilities include the possibility to map in situ, grain orientations, crystalline phase distribution, and full strain/stress tensors at a very local level, by combining white and monochromatic x-ray microbeam diffraction. This is particularly relevant for high technology industry where the understanding of material properties at a microstructural level becomes increasingly important. After describing the latest advances in the submicron x-ray diffraction techniques at the Advanced Light Source, we will give some examples of its application in material science for the measurement of strain/stress in metallic thin films and interconnects. Its use in the field of environmental science will also be discussed.

Towards a 4{sup th} generation storage ring at the Canadian Light Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dallin, Les; Wurtz, Ward

2016-07-27

Demands from beamline scientists for more brilliant sources of synchrotron radiation have resulted in the emergence of 4{sup th} generation (diffraction-limited) storage rings. The practical development of the multi-bend achromat (MBA) concept by MAX IV lab has spurred many synchrotron light sources around the world to develop similar machines. For existing facilities two options are available: upgrading existing machines or building a new structure. The Canadian Light Source (CLS) has explored both options. For a new low emittance source in the existing CLS tunnel a decrease in electron energy would be required. A machine similar to the ALS upgrade couldmore » be contemplated. To achieve low emittance at our present energy of 2.9 GeV a new storage ring is desirable. Several options have been investigated. These designs use extremely strong focusing magnets to achieve extremely low emittances in compact lattice achromats.« less

Clustering procedures for the optimal selection of data sets from multiple crystals in macromolecular crystallography.

PubMed

Foadi, James; Aller, Pierre; Alguel, Yilmaz; Cameron, Alex; Axford, Danny; Owen, Robin L; Armour, Wes; Waterman, David G; Iwata, So; Evans, Gwyndaf

2013-08-01

The availability of intense microbeam macromolecular crystallography beamlines at third-generation synchrotron sources has enabled data collection and structure solution from microcrystals of <10 µm in size. The increased likelihood of severe radiation damage where microcrystals or particularly sensitive crystals are used forces crystallographers to acquire large numbers of data sets from many crystals of the same protein structure. The associated analysis and merging of multi-crystal data is currently a manual and time-consuming step. Here, a computer program, BLEND, that has been written to assist with and automate many of the steps in this process is described. It is demonstrated how BLEND has successfully been used in the solution of a novel membrane protein.

Clustering procedures for the optimal selection of data sets from multiple crystals in macromolecular crystallography

PubMed Central

Foadi, James; Aller, Pierre; Alguel, Yilmaz; Cameron, Alex; Axford, Danny; Owen, Robin L.; Armour, Wes; Waterman, David G.; Iwata, So; Evans, Gwyndaf

2013-01-01

The availability of intense microbeam macromolecular crystallography beamlines at third-generation synchrotron sources has enabled data collection and structure solution from microcrystals of <10 µm in size. The increased likelihood of severe radiation damage where microcrystals or particularly sensitive crystals are used forces crystallographers to acquire large numbers of data sets from many crystals of the same protein structure. The associated analysis and merging of multi-crystal data is currently a manual and time-consuming step. Here, a computer program, BLEND, that has been written to assist with and automate many of the steps in this process is described. It is demonstrated how BLEND has successfully been used in the solution of a novel membrane protein. PMID:23897484

Linking structural biology with genome research: Beamlines for the Berlin ``Protein Structure Factory'' initiative

NASA Astrophysics Data System (ADS)

Illing, Gerd; Saenger, Wolfram; Heinemann, Udo

2000-06-01

The Protein Structure Factory will be established to characterize proteins encoded by human genes or cDNAs, which will be selected by criteria of potential structural novelty or medical or biotechnological usefulness. It represents an integrative approach to structure analysis combining bioinformatics techniques, automated gene expression and purification of gene products, generation of a biophysical fingerprint of the proteins and the determination of their three-dimensional structures either by NMR spectroscopy or by X-ray diffraction. The use of synchrotron radiation will be crucial to the Protein Structure Factory: high brilliance and tunable wavelengths are prerequisites for fast data collection, the use of small crystals and multiwavelength anomalous diffraction (MAD) phasing. With the opening of BESSY II, direct access to a third-generation XUV storage ring source with excellent conditions is available nearby. An insertion device with two MAD beamlines and one constant energy station will be set up until 2001.

Projection x-ray topography system at 1-BM x-ray optics test beamline at the advanced photon source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoupin, Stanislav, E-mail: sstoupin@aps.anl.gov; Liu, Zunping; Trakhtenberg, Emil

2016-07-27

Projection X-ray topography of single crystals is a classic technique for the evaluation of intrinsic crystal quality of large crystals. In this technique a crystal sample and an area detector (e.g., X-ray film) collecting intensity of a chosen crystallographic reflection are translated simultaneously across an X-ray beam collimated in the diffraction scattering plane (e.g., [1, 2]). A bending magnet beamline of a third-generation synchrotron source delivering x-ray beam with a large horizontal divergence, and therefore, a large horizontal beam size at a crystal sample position offers an opportunity to obtain X-ray topographs of large crystalline samples (e.g., 6-inch wafers) inmore » just a few exposures. Here we report projection X-ray topography system implemented recently at 1-BM beamline of the Advanced Photon Source. A selected X-ray topograph of a 6-inch wafer of 4H-SiC illustrates capabilities and limitations of the technique.« less

BioSAXS Sample Changer: a robotic sample changer for rapid and reliable high-throughput X-ray solution scattering experiments

PubMed Central

Round, Adam; Felisaz, Franck; Fodinger, Lukas; Gobbo, Alexandre; Huet, Julien; Villard, Cyril; Blanchet, Clement E.; Pernot, Petra; McSweeney, Sean; Roessle, Manfred; Svergun, Dmitri I.; Cipriani, Florent

2015-01-01

Small-angle X-ray scattering (SAXS) of macromolecules in solution is in increasing demand by an ever more diverse research community, both academic and industrial. To better serve user needs, and to allow automated and high-throughput operation, a sample changer (BioSAXS Sample Changer) that is able to perform unattended measurements of up to several hundred samples per day has been developed. The Sample Changer is able to handle and expose sample volumes of down to 5 µl with a measurement/cleaning cycle of under 1 min. The samples are stored in standard 96-well plates and the data are collected in a vacuum-mounted capillary with automated positioning of the solution in the X-ray beam. Fast and efficient capillary cleaning avoids cross-contamination and ensures reproducibility of the measurements. Independent temperature control for the well storage and for the measurement capillary allows the samples to be kept cool while still collecting data at physiological temperatures. The Sample Changer has been installed at three major third-generation synchrotrons: on the BM29 beamline at the European Synchrotron Radiation Facility (ESRF), the P12 beamline at the PETRA-III synchrotron (EMBL@PETRA-III) and the I22/B21 beamlines at Diamond Light Source, with the latter being the first commercial unit supplied by Bruker ASC. PMID:25615861

X-Ray Structure determination of the Glycine Cleavage System Protein H of Mycobacterium tuberculosis Using An Inverse Compton Synchrotron X-Ray Source

PubMed Central

Abendroth, Jan; McCormick, Michael S.; Edwards, Thomas E.; Staker, Bart; Loewen, Roderick; Gifford, Martin; Rifkin, Jeff; Mayer, Chad; Guo, Wenjin; Zhang, Yang; Myler, Peter; Kelley, Angela; Analau, Erwin; Hewitt, Stephen Nakazawa; Napuli, Alberto J.; Kuhn, Peter; Ruth, Ronald D.; Stewart, Lance J.

2010-01-01

Structural genomics discovery projects require ready access to both X-ray and NMR instrumentation which support the collection of experimental data needed to solve large numbers of novel protein structures. The most productive X-ray crystal structure determination laboratories make extensive frequent use of tunable synchrotron X-ray light to solve novel structures by anomalous diffraction methods. This requires that frozen cryo-protected crystals be shipped to large government-run synchrotron facilities for data collection. In an effort to eliminate the need to ship crystals for data collection, we have developed the first laboratory-scale synchrotron light source capable of performing many of the state-of-the-art synchrotron applications in X-ray science. This Compact Light Source is a first-in-class device that uses inverse Compton scattering to generate X-rays of sufficient flux, tunable wavelength and beam size to allow high-resolution X-ray diffraction data collection from protein crystals. We report on benchmarking tests of X-ray diffraction data collection with hen egg white lysozyme, and the successful high-resolution X-ray structure determination of the Glycine cleavage system protein H from Mycobacterium tuberculosis using diffraction data collected with the Compact Light Source X-ray beam. PMID:20364333

Latest developments at the ALBA magnetic measurements laboratory

NASA Astrophysics Data System (ADS)

Marcos, J.; Massana, V.; García, L.; Campmany, J.

2018-02-01

ALBA is a third-generation synchrotron light source that has been in operation since 2012 near Barcelona. A magnetic measurements laboratory has been associated with the facility since its very early stages and has been active for the last 20 years. In the first part of this work, the different instruments available at the laboratory are described, and a brief overview of the measurement campaigns carried out during its 20 years of history is presented. In the second part, a more detailed description of the approach to Hall probe measurements adopted at ALBA is offered, with an explanation of the methods and ancillary equipment that have been developed along the years in order to improve the accuracy of the system. In the third part, a new concept of Hall probe bench devoted to the measurement of closed structures is presented. The in-house design and building of a prototype for such a bench is described, together with its mechanical and magnetic characterization. As a conclusion, the first results obtained with this bench are discussed.

The Bonn Electron Stretcher Accelerator ELSA: Past and future

NASA Astrophysics Data System (ADS)

Hillert, W.

2006-05-01

In 1953, it was decided to build a 500MeV electron synchrotron in Bonn. It came into operation 1958, being the first alternating gradient synchrotron in Europe. After five years of performing photoproduction experiments at this accelerator, a larger 2.5GeV electron synchrotron was built and set into operation in 1967. Both synchrotrons were running for particle physics experiments, until from 1982 to 1987 a third accelerator, the electron stretcher ring ELSA, was constructed and set up in a separate ring tunnel below the physics institute. ELSA came into operation in 1987, using the pulsed 2.5GeV synchrotron as pre-accelerator. ELSA serves either as storage ring producing synchrotron radiation, or as post-accelerator and pulse stretcher. Applying a slow extraction close to a third integer resonance, external electron beams with energies up to 3.5GeV and high duty factors are delivered to hadron physics experiments. Various photo- and electroproduction experiments, utilising the experimental set-ups PHOENICS, ELAN, SAPHIR, GDH and Crystal Barrel have been carried out. During the late 90's, a pulsed GaAs source of polarised electrons was constructed and set up at the accelerator. ELSA was upgraded in order to accelerate polarised electrons, compensating for depolarising resonances by applying the methods of fast tune jumping and harmonic closed orbit correction. With the experimental investigation of the GDH sum rule, the first experiment requiring a polarised beam and a polarised target was successfully performed at the accelerator. In the near future, the stretcher ring will be further upgraded to increase polarisation and current of the external electron beams. In addition, the aspects of an increase of the maximum energy to 5GeV using superconducting resonators will be investigated.

PEP as a synchrotron radiation source (invited)

NASA Astrophysics Data System (ADS)

Bienenstock, A.; Brown, G.; Wiedemann, H.; Winick, H.

1989-07-01

The 16-GeV storage ring PEP has characteristics which enable it to operate in modes with very low emittance and to accommodate very long undulators, producing synchrotron radiation at x-ray wavelengths with extremely high brightness and coherent power. Two beamlines, each illuminated by a 2-m long, 77-mm period undulator magnet, are now operational and others are planned. In parasitic operation during colliding-beam runs at 14.5 GeV, these beamlines provide photons above 10 keV with a peak brightness of about 1016 photons/(s mm2 mrad2 ) within a 0.1% bandwidth. In low-emittance tests at 7.1 GeV, horizontal emittances of about 5 nm rad were measured, which is about the same as that planned for the new third-generation x-ray sources. With a current of 15 mA at 7.1 GeV, the present undulators deliver photon beams from 2.7 to 14 keV with a peak brightness of about 1017 . Higher performance levels are expected with the implementation of longer undulators and shorter period undulators. In the longer term, because of its large circumference and long straight sections, PEP could be further developed to achieve even higher performance levels with an emittance below 1 nm rad, very long undulators and picosecond bunches, resulting in one to two orders of magnitude higher brightness and coherent power.

Geometrical and wave optics of paraxial beams.

PubMed

Meron, M; Viccaro, P J; Lin, B

1999-06-01

Most calculational techniques used to evaluate beam propagation are geared towards either fully coherent or fully incoherent beams. The intermediate partial-coherence regime, while in principle known for a long time, has received comparably little attention so far. The resulting shortage of adequate calculational techniques is currently being felt in the realm of x-ray optics where, with the advent of third generation synchrotron light sources, partially coherent beams become increasingly common. The purpose of this paper is to present a calculational approach which, utilizing a "variance matrix" representation of paraxial beams, allows for a straightforward evaluation of wave propagation through an optical system. Being capable of dealing with an arbitrary degree of coherence, this approach covers the whole range from wave to ray optics, in a seamless fashion.

Diffraction-Enhanced Computed Tomographic Imaging of Growing Piglet Joints by Using a Synchrotron Light Source

PubMed Central

Rhoades, Glendon W; Belev, George S; Chapman, L Dean; Wiebe, Sheldon P; Cooper, David M; Wong, Adelaine TF; Rosenberg, Alan M

2015-01-01

The objective of this project was to develop and test a new technology for imaging growing joints by means of diffraction-enhanced imaging (DEI) combined with CT and using a synchrotron radiation source. DEI–CT images of an explanted 4-wk-old piglet stifle joint were acquired by using a 40-keV beam. The series of scanned slices was later ‘stitched’ together, forming a 3D dataset. High-resolution DEI-CT images demonstrated fine detail within all joint structures and tissues. Striking detail of vasculature traversing between bone and cartilage, a characteristic of growing but not mature joints, was demonstrated. This report documents for the first time that DEI combined with CT and a synchrotron radiation source can generate more detailed images of intact, growing joints than can currently available conventional imaging modalities. PMID:26310464

Synchrotron Radiation Workshop (SRW)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chubar, O.; Elleaume, P.

2013-03-01

"Synchrotron Radiation Workshop" (SRW) is a physical optics computer code for calculation of detailed characteristics of Synchrotron Radiation (SR) generated by relativistic electrons in magnetic fields of arbitrary configuration and for simulation of the radiation wavefront propagation through optical systems of beamlines. Frequency-domain near-field methods are used for the SR calculation, and the Fourier-optics based approach is generally used for the wavefront propagation simulation. The code enables both fully- and partially-coherent radiation propagation simulations in steady-state and in frequency-/time-dependent regimes. With these features, the code has already proven its utility for a large number of applications in infrared, UV, softmore » and hard X-ray spectral range, in such important areas as analysis of spectral performances of new synchrotron radiation sources, optimization of user beamlines, development of new optical elements, source and beamline diagnostics, and even complete simulation of SR based experiments. Besides the SR applications, the code can be efficiently used for various simulations involving conventional lasers and other sources. SRW versions interfaced to Python and to IGOR Pro (WaveMetrics), as well as cross-platform library with C API, are available.« less

Additional Spitzer IRS Spectroscopy of Three Intermediate Polars: The Detection of a Mid-infrared Synchrotron Flare from V1223 Sagittarii

NASA Astrophysics Data System (ADS)

Harrison, Thomas E.; Bornak, Jillian; Rupen, Michael P.; Howell, Steve B.

2010-02-01

We present new Spitzer Infrared Spectrograph (IRS) observations of three intermediate polars: V1223 Sgr, EX Hya, and V603 Aql. We detected a strong, fading flare event from V1223 Sgr. During this event, the flux declined by a factor of 13 in 30 minutes. Given the similarity in the slope of its mid-infrared spectrum during this event to that of AE Aqr, we suggest that this event was caused by transient synchrotron emission. Thus, V1223 Sgr becomes the third cataclysmic variable known to be a synchrotron source. We were unable to confirm the mid-infrared excess noted by Harrison et al. (Paper I) for EX Hya, suggesting that this object is either not a synchrotron source, or is slightly variable. Due to a very high background, V603 Aql was not detected in the long-wavelength regions accessible to the IRS. Given the recent detection of SS Cygni at radio wavelengths during outburst, we extract archival Spitzer IRS spectra for this source obtained during two successive maxima. These spectra do not show a strong excess, but without simultaneous data at shorter wavelengths, it is not possible to determine whether there is any contribution to the mid-infrared fluxes from a synchrotron jet. Includes observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).

Ultra high-speed x-ray imaging of laser-driven shock compression using synchrotron light

NASA Astrophysics Data System (ADS)

Olbinado, Margie P.; Cantelli, Valentina; Mathon, Olivier; Pascarelli, Sakura; Grenzer, Joerg; Pelka, Alexander; Roedel, Melanie; Prencipe, Irene; Laso Garcia, Alejandro; Helbig, Uwe; Kraus, Dominik; Schramm, Ulrich; Cowan, Tom; Scheel, Mario; Pradel, Pierre; De Resseguier, Thibaut; Rack, Alexander

2018-02-01

A high-power, nanosecond pulsed laser impacting the surface of a material can generate an ablation plasma that drives a shock wave into it; while in situ x-ray imaging can provide a time-resolved probe of the shock-induced material behaviour on macroscopic length scales. Here, we report on an investigation into laser-driven shock compression of a polyurethane foam and a graphite rod by means of single-pulse synchrotron x-ray phase-contrast imaging with MHz frame rate. A 6 J, 10 ns pulsed laser was used to generate shock compression. Physical processes governing the laser-induced dynamic response such as elastic compression, compaction, pore collapse, fracture, and fragmentation have been imaged; and the advantage of exploiting the partial spatial coherence of a synchrotron source for studying low-density, carbon-based materials is emphasized. The successful combination of a high-energy laser and ultra high-speed x-ray imaging using synchrotron light demonstrates the potentiality of accessing complementary information from scientific studies of laser-driven shock compression.

Characterization and long term operation of a novel superconducting undulator with 15 mm period length in a synchrotron light source

NASA Astrophysics Data System (ADS)

Casalbuoni, S.; Cecilia, A.; Gerstl, S.; Glamann, N.; Grau, A. W.; Holubek, T.; Meuter, C.; de Jauregui, D. Saez; Voutta, R.; Boffo, C.; Gerhard, Th.; Turenne, M.; Walter, W.

2016-11-01

A new cryogen-free full scale (1.5 m long) superconducting undulator with a period length of 15 mm (SCU15) has been successfully tested in the ANKA storage ring. This represents a very important milestone in the development of superconducting undulators for third and fourth generation light sources carried on by the collaboration between the Karlsruhe Institute of Technology and the industrial partner Babcock Noell GmbH. SCU15 is the first full length device worldwide that with beam reaches a higher peak field than what expected with the same geometry (vacuum gap and period length) with an ideal cryogenic permanent magnet undulator built with the best material available PrFeB. After a summary on the design and main parameters of the device, we present here the characterization in terms of spectral properties and the long term operation of the SCU15 in the ANKA storage ring.

Differential phase contrast with a segmented detector in a scanning X-ray microprobe

PubMed Central

Hornberger, B.; de Jonge, M. D.; Feser, M.; Holl, P.; Holzner, C.; Jacobsen, C.; Legnini, D.; Paterson, D.; Rehak, P.; Strüder, L.; Vogt, S.

2008-01-01

Scanning X-ray microprobes are unique tools for the nanoscale investigation of specimens from the life, environmental, materials and other fields of sciences. Typically they utilize absorption and fluorescence as contrast mechanisms. Phase contrast is a complementary technique that can provide strong contrast with reduced radiation dose for weakly absorbing structures in the multi-keV range. In this paper the development of a segmented charge-integrating silicon detector which provides simultaneous absorption and differential phase contrast is reported. The detector can be used together with a fluorescence detector for the simultaneous acquisition of transmission and fluorescence data. It can be used over a wide range of photon energies, photon rates and exposure times at third-generation synchrotron radiation sources, and is currently operating at two beamlines at the Advanced Photon Source. Images obtained at around 2 keV and 10 keV demonstrate the superiority of phase contrast over absorption for specimens composed of light elements. PMID:18552427

Covariance mapping of two-photon double core hole states in C 2 H 2 and C 2 H 6 produced by an x-ray free electron laser

DOE PAGES

Mucke, M; Zhaunerchyk, V; Frasinski, L J; ...

2015-07-01

Few-photon ionization and relaxation processes in acetylene (C 2H 2) and ethane (C 2H 6) were investigated at the linac coherent light source x-ray free electron laser (FEL) at SLAC, Stanford using a highly efficient multi-particle correlation spectroscopy technique based on a magnetic bottle. The analysis method of covariance mapping has been applied and enhanced, allowing us to identify electron pairs associated with double core hole (DCH) production and competing multiple ionization processes including Auger decay sequences. The experimental technique and the analysis procedure are discussed in the light of earlier investigations of DCH studies carried out at the samemore » FEL and at third generation synchrotron radiation sources. In particular, we demonstrate the capability of the covariance mapping technique to disentangle the formation of molecular DCH states which is barely feasible with conventional electron spectroscopy methods.« less

APS Storage Ring Monopulse RF BPM Upgrade

NASA Astrophysics Data System (ADS)

Lill, R.; Pietryla, A.; Norum, E.; Lenkszus, F.

2004-11-01

The Advanced Photon Source (APS) is a third-generation synchrotron light source in its ninth year of operation. The storage ring monopulse radio frequency (rf) beam position monitor (BPM) was designed to measure single-turn and multi-turn beam positions for operations and machine physics studies. Many of the components used in the original design are obsolete and costly to replace. In this paper we present a proposal to upgrade the monopulse rf BPMs in which the existing system hardware is repartitioned and the aging data acquisition system is replaced. By replacing only the data acquisition system, we will demonstrate a cost-effective approach to improved beam stability, reliability, and enhanced postmortem capabilities. An eight-channel ADC/digitizer VXI board with sampling rate of up to 105 MHz (per channel) and 14-bit resolution coupled with a field-programmable gate array and embedded central processing will provide the flexibility to revitalize this system for another decade of operation. We will discuss the upgrade system specifications, design, and prototype test results.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolme, Cynthia Anne; Glenzer, Sigfried; Fry, Alan

On October 5–6, 2015, the third international user workshop focusing on high-power lasers at the Linac Coherent Light Source (LCLS) was held in Menlo Park, CA, USA [1 R. Falcone, S. Glenzer, and S. Hau-Riege, Synchrotron Radiation News 27(2), 56–58 (2014)., 2 P. Heimann and S. Glenzer, Synchrotron Radiation News 28(3), 54–56 (2015).]. Here, the workshop was co-organized by Los Alamos National Laboratory and SLAC National Accelerator Laboratory. More than 110 scientists attended from North America, Europe, and Asia to discuss high-energy-density (HED) science that is enabled by the unique combination of high-power lasers with the LCLS X-rays at themore » LCLS-Matter in Extreme Conditions (MEC) endstation.« less

Kalman-Predictive-Proportional-Integral-Derivative (KPPID) Temperature Control

NASA Astrophysics Data System (ADS)

Fluerasu, Andrei; Sutton, Mark

2003-09-01

With third generation synchrotron X-ray sources, it is possible to acquire detailed structural information about the system under study with time resolution orders of magnitude faster than was possible a few years ago. These advances have generated many new challenges for changing and controlling the state of the system on very short time scales, in a uniform and controlled manner. For our particular X-ray experiments [1] on crystallization or order-disorder phase transitions in metallic alloys, we need to change the sample temperature by hundreds of degrees as fast as possible while avoiding over or under shooting. To achieve this, we designed and implemented a computer-controlled temperature tracking system which combines standard Proportional-Integral-Derivative (PID) feedback, thermal modeling and finite difference thermal calculations (feedforward), and Kalman filtering of the temperature readings in order to reduce the noise. The resulting Kalman-Predictive-Proportional-Integral-Derivative (KPPID) algorithm allows us to obtain accurate control, to minimize the response time and to avoid over/under shooting, even in systems with inherently noisy temperature readings and time delays. The KPPID temperature controller was successfully implemented at the Advanced Photon Source at Argonne National Laboratories and was used to perform coherent and time-resolved X-ray diffraction experiments.

Expected thermal deformation and wavefront preservation of a cryogenic Si monochromator for Cornell ERL beamlines

PubMed Central

Huang, Rong; Bilderback, Donald H.; Finkelstein, Kenneth

2014-01-01

Cornell energy-recovery linac (ERL) beamlines will have higher power density and higher fractional coherence than those available at third-generation sources; therefore the capability of a monochromator for ERL beamlines has to be studied. A cryogenic Si monochromator is considered in this paper because the perfect atomic structure of Si crystal is needed to deliver highly coherent radiation. Since neither the total heat load nor the power density alone can determine the severity of crystal deformation, a metric called modified linear power density is used to gauge the thermal deformation. For all ERL undulator beamlines, crystal thermal deformation profiles are simulated using the finite-element analysis tool ANSYS, and wavefront propagations are simulated using Synchrotron Radiation Workshop. It is concluded that cryogenic Si monochromators will be suitable for ERL beamlines in general. PMID:24562557

Studies of beam injection with a compensated bump and uncompensated bump in a synchrotron

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akbar Fakhri, Ali; Prajapati, S. K.; Ghodke, A. D.

2013-08-15

Synchrotron radiation sources Indus-1 and Indus-2 have a synchrotron as the common injector. A three kicker compensated bump injection scheme was employed for beam injection into this synchrotron. The stored beam current in the synchrotron is higher, when all the three kickers are operated at the same current than when kickers are operated at currents required to generate compensated bump. Beam dynamics studies have been done to understand why this happens. Theoretical studies indicate that higher stored current in the later case is attributed to smaller residual oscillations of injected beam. These studies also reveal that if the angle ofmore » the injected beam during beam injection is kept varying, the performance could be further improved. This is experimentally confirmed by injecting the beam on rising part of the injection septum magnet current pulse.« less

A compact 500 MHz 4 kW Solid-State Power Amplifier for accelerator applications

NASA Astrophysics Data System (ADS)

Gaspar, M.; Pedrozzi, M.; Ferreira, L. F. R.; Garvey, T.

2011-05-01

We present the development of a compact narrow-band Solid-State Power Amplifier (SSPA). We foresee a promising application of solid-state amplifiers specifically in accelerators for new generation synchrotron light sources. Such a new technology has reached a competitive price/performance ratio and expected lifetime in comparison with klystron and IOT amplifiers. The increasing number of synchrotron light sources using 500 MHz as base frequency justifies the effort in the development of the proposed amplifier. Two different techniques are also proposed to improve the control and performance of these new distributed amplification systems which we call, respectively, complete distributed system and forced compression.

Fourth Generation Light Sources

NASA Astrophysics Data System (ADS)

Winick, Herman

1997-05-01

Concepts and designs are now being developed at laboratories around the world for light sources with performance levels that exceed present sources, including the very powerful and successful third generation synchrotron radiation sources that have come on line in the past few years. Workshops (M. Cornacchia and H. Winick (eds), Workshop on Fourth Generation Light Sources, Feb. 24-27, 1992, SSRL Report 92/02) (J.-L. Laclare (ed), ICFA Workshop on Fourth Generation Light Sources, Jan. 22-25, 1996, ESRF Report) have been held to review directions for future sources. A main thrust is to increase the brightness and coherence of the radiation using storage rings with lower electron-beam emittance or free-electron lasers (FELs). In the infra-red part of the spectrum very high brightness and coherence is already provided by FEL user facilities driven by linacs and storage rings. It now appears possible to extend FEL operation to the VUV, soft X-ray and even hard X-ray spectral range, to wavelengths down to the angstrom range, using high energy linacs equipped with high-brightness rf photoinjectors and bunch-length compressors. R&D to develop such sources is in progress at BNL, DESY, KEK, SLAC and other laboratories. In the absence of mirrors to form optical cavities, short wavelengths are reached in FEL systems in which a high peak current, low-emittance electron beam becomes bunch-density modulated at the optical wavelength in a single pass through a long undulator by self-amplified spontaneous emission (SASE); i.e.; startup from noise. A proposal to use the last kilometer of the three kilometer SLAC linac (the first two kilometers will be used for injection to the PEP II B-Factory) to provide 15 GeV electron beams to reach 1.5 Angstroms by SASE in a 100 m long undulator is in preparation.

RELATIVISTIC THOMSON SCATTERING EXPERIMENT AT BNL - STATUS REPORT.

DOE Office of Scientific and Technical Information (OSTI.GOV)

POGORELSKY,I.V.; BEN ZVI,I.; KUSCHE,K.

2001-12-03

1.7 x 10{sup 8} x-ray photons per 3.5 ps pulse have been produced in Thomson scattering by focusing CO{sub 2} laser pulse on counter-propagating relativistic electron beam. We explore a possibility of further enhancement of process efficiency by propagating both beams in a plasma capillary. Conventional synchrotron light sources based on using giga-electron-volt electron synchrotron accelerators and magnetic wigglers generate x-ray radiation for versatile application in multi-disciplinary research. An intense laser beam causes relativistic electron oscillations similar to a wiggler. However, because the laser wavelength is thousand times shorter than a wiggler period, very moderate electron energy is needed tomore » produce hard x-rays via Thomson scattering. This allows using relatively compact mega-electron-volt linear accelerators instead of giga-electron-volt synchrotrons. Another important advantage of Thomson sources is a possibility to generate femtosecond x-ray pulses whereas conventional synchrotron sources have typically {approx}300 ps pulse duration. This promises to revolutionize x-ray research in chemistry, physics, and biology expanding it to ultra-fast processes. Thomson sources do not compete in repetition rate and average intensity with conventional light sources that operate at the megahertz frequency. However, Thomson sources have a potential to produce much higher photon numbers per pulse. This may allow developing a single shot exposure important for structural analysis of live biological objects. The BNL Thomson source is a user's experiment conducted at the Accelerator Test Facility since 1998 by an international collaboration in High Energy Physics. Since inception, the ATF source produces the record peak x-ray yield, intensity and brightness among other similar proof-of-principle demonstrations attempted elsewhere. Note that this result is achieved with a moderate laser power of 15 GW. A key to this achievement is in choosing right apparatus and efficient interaction geometry. We use a CO{sub 2} laser that delivers 10 times more photons per unit energy than the 1-{micro}m laser, a high-brightness linac, and the most energy-efficient backscattering interaction geometry. The purpose of this report is to give an update on new results obtained during this year and our near-term plans.« less

'Taking X-ray phase contrast imaging into mainstream applications' and its satellite workshop 'Real and reciprocal space X-ray imaging'.

PubMed

Olivo, Alessandro; Robinson, Ian

2014-03-06

A double event, supported as part of the Royal Society scientific meetings, was organized in February 2013 in London and at Chicheley Hall in Buckinghamshire by Dr A. Olivo and Prof. I. Robinson. The theme that joined the two events was the use of X-ray phase in novel imaging approaches, as opposed to conventional methods based on X-ray attenuation. The event in London, led by Olivo, addressed the main roadblocks that X-ray phase contrast imaging (XPCI) is encountering in terms of commercial translation, for clinical and industrial applications. The main driver behind this is the development of new approaches that enable XPCI, traditionally a synchrotron method, to be performed with conventional laboratory sources, thus opening the way to its deployment in clinics and industrial settings. The satellite meeting at Chicheley Hall, led by Robinson, focused on the new scientific developments that have recently emerged at specialized facilities such as third-generation synchrotrons and free-electron lasers, which enable the direct measurement of the phase shift induced by a sample from intensity measurements, typically in the far field. The two events were therefore highly complementary, in terms of covering both the more applied/translational and the blue-sky aspects of the use of phase in X-ray research. 

Synchrotron Radiation Research--An Overview.

ERIC Educational Resources Information Center

Bienenstock, Arthur; Winick, Herman

1983-01-01

Discusses expanding user community seeking access to synchrotron radiation sources, properties/sources of synchrotron radiation, permanent-magnet technology and its impact on synchrotron radiation research, factors limiting power, the density of synchrotron radiation, and research results illustrating benefit of higher flux and brightness. Also…

452nd Brookhaven Lecture. Extreme Environments of Next-Generation Energy Systems and Materials: Can They Peacefully Co-Exist?

ScienceCinema

Simos, Nikolaos

2017-12-22

Nikolaos Simos of Brookhaven’s Energy Sciences and Technology Department and the National Synchrotron Light Source II Project presents, “Extreme Environments of Next-Generation Energy Systems and Materials: Can They Peacefully Co-Exist?”

Characterization of a next-generation piezo bimorph X-ray mirror for synchrotron beamlines

PubMed Central

Alcock, Simon G.; Nistea, Ioana; Sutter, John P.; Sawhney, Kawal; Fermé, Jean-Jacques; Thellièr, Christophe; Peverini, Luca

2015-01-01

Piezo bimorph mirrors are versatile active optics used on many synchrotron beamlines. However, many bimorphs suffer from the ‘junction effect’: a periodic deformation of the optical surface which causes major aberrations to the reflected X-ray beam. This effect is linked to the construction of such mirrors, where piezo ceramics are glued directly below the thin optical substrate. In order to address this problem, a next-generation bimorph with piezos bonded to the side faces of a monolithic substrate was developed at Thales-SESO and optimized at Diamond Light Source. Using metrology feedback from the Diamond-NOM, the optical slope error was reduced to ∼0.5 µrad r.m.s. for a range of ellipses. To maximize usability, a novel holder was built to accommodate the substrate in any orientation. When replacing a first-generation bimorph on a synchrotron beamline, the new mirror significantly improved the size and shape of the reflected X-ray beam. Most importantly, there was no evidence of the junction effect even after eight months of continuous beamline usage. It is hoped that this new design will reinvigorate the use of active bimorph optics at synchrotron and free-electron laser facilities to manipulate and correct X-ray wavefronts. PMID:25537582

Characterization of a next-generation piezo bimorph X-ray mirror for synchrotron beamlines.

PubMed

Alcock, Simon G; Nistea, Ioana; Sutter, John P; Sawhney, Kawal; Fermé, Jean Jacques; Thellièr, Christophe; Peverini, Luca

2015-01-01

Piezo bimorph mirrors are versatile active optics used on many synchrotron beamlines. However, many bimorphs suffer from the `junction effect': a periodic deformation of the optical surface which causes major aberrations to the reflected X-ray beam. This effect is linked to the construction of such mirrors, where piezo ceramics are glued directly below the thin optical substrate. In order to address this problem, a next-generation bimorph with piezos bonded to the side faces of a monolithic substrate was developed at Thales-SESO and optimized at Diamond Light Source. Using metrology feedback from the Diamond-NOM, the optical slope error was reduced to ∼ 0.5 µrad r.m.s. for a range of ellipses. To maximize usability, a novel holder was built to accommodate the substrate in any orientation. When replacing a first-generation bimorph on a synchrotron beamline, the new mirror significantly improved the size and shape of the reflected X-ray beam. Most importantly, there was no evidence of the junction effect even after eight months of continuous beamline usage. It is hoped that this new design will reinvigorate the use of active bimorph optics at synchrotron and free-electron laser facilities to manipulate and correct X-ray wavefronts.

SESAME-A 3rd Generation Synchrotron Light Source for the Middle East

NASA Astrophysics Data System (ADS)

Winick, Herman

2010-02-01

Developed under the auspices of UNESCO and modeled on CERN, SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is an international research center in construction in Jordan. It will enable world class research by scientists from the region, reversing the brain drain. It will also build bridges between diverse societies, contributing to a culture of peace through international cooperation in science. The centerpiece is a synchrotron light source originating from BESSY I, a gift by Germany. The upgraded machine, a 2.5 GeV 3rd Generation Light Source (133m circumference, 26nm-rad emittance and 12 places for insertion devices), will provide light from infra-red to hard X-rays, offering excellent opportunities to train local scientists and attract those working abroad to return. The SESAME Council meets twice each year and presently has nine Members (Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, Palestinian Authority, Turkey). Members have responsibility for the project and provide the annual operations budget (1.5M US dollars in 2009, expected to rise to about 5M when operation starts in 2012-13). Jordan provided the site, building, and infrastructure. A staff of 20 is installing the 0.8 GeV BESSY I injection system. The facility will have the capacity to serve 30 or more experiments operating simultaneously. See www.sesame.org.jo )

Structure determination of an integral membrane protein at room temperature from crystals in situ

DOE Office of Scientific and Technical Information (OSTI.GOV)

Axford, Danny; Foadi, James; Imperial College London, London SW7 2AZ

2015-05-14

The X-ray structure determination of an integral membrane protein using synchrotron diffraction data measured in situ at room temperature is demonstrated. The structure determination of an integral membrane protein using synchrotron X-ray diffraction data collected at room temperature directly in vapour-diffusion crystallization plates (in situ) is demonstrated. Exposing the crystals in situ eliminates manual sample handling and, since it is performed at room temperature, removes the complication of cryoprotection and potential structural anomalies induced by sample cryocooling. Essential to the method is the ability to limit radiation damage by recording a small amount of data per sample from many samplesmore » and subsequently assembling the resulting data sets using specialized software. The validity of this procedure is established by the structure determination of Haemophilus influenza TehA at 2.3 Å resolution. The method presented offers an effective protocol for the fast and efficient determination of membrane-protein structures at room temperature using third-generation synchrotron beamlines.« less

Characterization of polycrystalline materials using synchrotron X-ray imaging and diffraction techniques

NASA Astrophysics Data System (ADS)

Ludwig, W.; King, A.; Herbig, M.; Reischig, P.; Marrow, J.; Babout, L.; Lauridsen, E. M.; Proudhon, H.; Buffière, J. Y.

2010-12-01

The combination of synchrotron radiation x-ray imaging and diffraction techniques offers new possibilities for in-situ observation of deformation and damage mechanisms in the bulk of polycrystalline materials. Minute changes in electron density (i.e., cracks, porosities) can be detected using propagation based phase contrast imaging, a 3-D imaging mode exploiting the coherence properties of third generation synchrotron beams. Furthermore, for some classes of polycrystalline materials, one may use a 3-D variant of x-ray diffraction imaging, termed x-ray diffraction contrast tomography. X-ray diffraction contrast tomography provides access to the 3-D shape, orientation, and elastic strain state of the individual grains from polycrystalline sample volumes containing up to thousand grains. Combining both imaging modalities, one obtains a comprehensive description of the materials microstructure at the micrometer length scale. Repeated observation during (interrupted) mechanical tests provide unprecedented insight into crystallographic and grain microstructure related aspects of polycrystalline deformation and degradation mechanisms.

Laser Wakefield Accelerators: Next-Generation Light Sources

DOE PAGES

Albert, Felicie

2018-01-01

Here, a new breed of compact particle accelerators, capable of producing electron-beam energies in the GeV range, could soon bring some of the experimental power of synchrotrons and X-ray free-electron lasers to a tabletop near you.

Laser Wakefield Accelerators: Next-Generation Light Sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albert, Felicie

Here, a new breed of compact particle accelerators, capable of producing electron-beam energies in the GeV range, could soon bring some of the experimental power of synchrotrons and X-ray free-electron lasers to a tabletop near you.

Membrane protein structure determination — The next generation☆☆☆

PubMed Central

Moraes, Isabel; Evans, Gwyndaf; Sanchez-Weatherby, Juan; Newstead, Simon; Stewart, Patrick D. Shaw

2014-01-01

The field of Membrane Protein Structural Biology has grown significantly since its first landmark in 1985 with the first three-dimensional atomic resolution structure of a membrane protein. Nearly twenty-six years later, the crystal structure of the beta2 adrenergic receptor in complex with G protein has contributed to another landmark in the field leading to the 2012 Nobel Prize in Chemistry. At present, more than 350 unique membrane protein structures solved by X-ray crystallography (http://blanco.biomol.uci.edu/mpstruc/exp/list, Stephen White Lab at UC Irvine) are available in the Protein Data Bank. The advent of genomics and proteomics initiatives combined with high-throughput technologies, such as automation, miniaturization, integration and third-generation synchrotrons, has enhanced membrane protein structure determination rate. X-ray crystallography is still the only method capable of providing detailed information on how ligands, cofactors, and ions interact with proteins, and is therefore a powerful tool in biochemistry and drug discovery. Yet the growth of membrane protein crystals suitable for X-ray diffraction studies amazingly remains a fine art and a major bottleneck in the field. It is often necessary to apply as many innovative approaches as possible. In this review we draw attention to the latest methods and strategies for the production of suitable crystals for membrane protein structure determination. In addition we also highlight the impact that third-generation synchrotron radiation has made in the field, summarizing the latest strategies used at synchrotron beamlines for screening and data collection from such demanding crystals. This article is part of a Special Issue entitled: Structural and biophysical characterisation of membrane protein-ligand binding. PMID:23860256

Influence of synchrotron self-absorption on 21-cm experiments

NASA Astrophysics Data System (ADS)

Zheng, Qian; Wu, Xiang-Ping; Gu, Jun-Hua; Wang, Jingying; Xu, Haiguang

2012-08-01

The presence of spectral curvature resulting from the synchrotron self-absorption of extragalactic radio sources could break down the spectral smoothness feature. This leads to the premise that the bright radio foreground can be successfully removed in 21-cm experiments that search for the epoch of reionization (EoR). We present a quantitative estimate of the effect of the spectral curvature resulting from the synchrotron self-absorption of extragalactic radio sources on the measurement of the angular power spectrum of the low-frequency sky. We incorporate a phenomenological model, which is characterized by the fraction (f) of radio sources with turnover frequencies in the range of 100-1000 MHz and by a broken power law for the spectral transition around the turnover frequencies νm, into simulated radio sources over a small sky area of 10° × 10°. We compare statistically the changes in their residual maps with and without the inclusion of the synchrotron self-absorption of extragalactic radio sources after the bright sources of S150 MHz ≥100 mJy are excised. Furthermore, the best-fitting polynomials in the frequency domain on each pixel are subtracted. It has been shown that the effect of synchrotron self-absorption on the detection of the EoR depends sensitively on the spectral profiles of the radio sources around the turnover frequencies νm. A hard transition model, described by the broken power law with the turnover of spectral index at νm, would leave pronounced imprints on the residual background and would therefore cause serious confusion with the cosmic EoR signal. However, the spectral signatures on the angular power spectrum of the extragalactic foreground, generated by a soft transition model in which the rising and falling power laws of the spectral distribution around νm are connected through a smooth transition spanning ≥200 MHz in a characteristic width, can be fitted and consequently subtracted by the use of polynomials to an acceptable degree (δT < 1 mK). As this latter scenario seems to be favoured in both theoretical expectations and radio spectral observations, we conclude that the contamination of extragalactic radio sources by synchrotron self-absorption in 21-cm experiments is probably very minor.

Emittance and lifetime measurement with damping wigglers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, G. M.; Shaftan, T., E-mail: shaftan@bnl.gov; Cheng, W. X.

National Synchrotron Light Source II (NSLS-II) is a new third-generation storage ring light source at Brookhaven National Laboratory. The storage ring design calls for small horizontal emittance (<1 nm-rad) and diffraction-limited vertical emittance at 12 keV (8 pm-rad). Achieving low value of the beam size will enable novel user experiments with nm-range spatial and meV-energy resolution. The high-brightness NSLS-II lattice has been realized by implementing 30-cell double bend achromatic cells producing the horizontal emittance of 2 nm rad and then halving it further by using several Damping Wigglers (DWs). This paper is focused on characterization of the DW effects inmore » the storage ring performance, namely, on reduction of the beam emittance, and corresponding changes in the energy spread and beam lifetime. The relevant beam parameters have been measured by the X-ray pinhole camera, beam position monitors, beam filling pattern monitor, and current transformers. In this paper, we compare the measured results of the beam performance with analytic estimates for the complement of the 3 DWs installed at the NSLS-II.« less

Survey and Alighment for the ALS Project at LBL Berkeley

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keller, R.; Lauritzen, T.; /LBL, Berkeley

2005-08-12

The Advanced Light Source (ALS), now under construction at Lawrence Berkeley Laboratory, is a synchrotron radiation source of the third generation designed to produce extremely bright photon beams in the UV and soft X-ray regions. Its main accelerator components are a 1-1.9 GeV electron storage ring with 196.8 m circumference and 12 super-periods, a 1.5 GeV booster synchrotron with 75.0 m circumference and 4 super-periods, and a 50 MeV linac, as shown in Fig. 1. The storage ring has particularly tight positioning tolerances for lattice magnets and other components to assure the required operational characteristics. The general survey and alignmentmore » concept for the ALS is based on a network of fixed monuments installed in the building floor, to which all component positions are referred. Measurements include electronic distance measurements and separate sightings for horizontal and vertical directions, partially with automated electronic data capture. Most of the data processing is accomplished by running a customized version of PC-GEONET. It provides raw data storage, data reduction, and the calculation of adjusted coordinates, as well as an option for error analysis. PC-GEONET has also been used to establish an observation plan for the monuments and calculate their expected position accuracies, based on approximate coordinates. Additionally, for local survey tasks, the commercial software package ECDS is used. In this paper, the ALS survey and alignment strategy and techniques are presented and critically discussed. First experiences with the alignment of the linac and booster components are described.« less

Signatures of Synchrotron: Low-cutoff X-ray emission and the hard X-ray spectrum of Cas A

NASA Astrophysics Data System (ADS)

Stage, Michael D.; Fedor, Emily Elizabeth; Martina-Hood, Hyourin

2018-06-01

In soft X-rays, bright, young Galactic remnants (Cas A, Kepler, Tycho, etc.) present thermal line emission and bremsstrahlung from ejecta, and synchrotron radiation from the shocks. Their hard X-ray spectra tend to be dominated by power-law sources. However, it can be non-trivial to discriminate between contributions from processes such as synchrotron and bremsstrahlung from nonthermally accelerated electrons, even though the energies of the electrons producing this radiation may be very different. Spatially-resolved spectroscopic analysis of 0.5-10 keV observations with, e.g., Chandracan provide leverage in identifying the processes and their locations. Previously, Stage & Allen (2006), Allen & Stage (2007) and Stage & Allen (2011) identified regions characterized by high-cutoff synchrotron radiation. Extrapolating synchrotron model fits to the emission in the Chandra band, they estimated the synchrotron contribution to the hard X-ray spectrum at about one-third the observed flux, fitting the balance with nonthermal bremsstrahlung emission produced by nonthermal electrons in the ejecta. Although it is unlikely this analysis missed regions of the highest-cutoff synchrotron emission, which supplies the bulk of the synchrotron above 15 keV, it may have missed regions of lower-cutoff emission, especially if they are near bright ejecta and the reverse shock. These regions cannot explain the emission at the highest energies (~50 keV), but may make significant contributions to the hard spectrum at lower energies (~10 keV). Using the technique described in Fedor, Martina-Hood & Stage (this meeting), we revisit the analysis to include regions that may be dominated by low-cutoff synchrotron, located in the interior of the remnant, and/or correlated with the reverse shock. Identifying X-ray emission from accelerated electrons associated with the reverse-shock would have important implications for synchrotron and non-thermal bremsstrahlung radiation above the 10 keV.

Towards a table-top synchrotron based on supercontinuum generation

NASA Astrophysics Data System (ADS)

Petersen, Christian R.; Moselund, Peter M.; Huot, Laurent; Hooper, Lucy; Bang, Ole

2018-06-01

Recently, high brightness and broadband supercontinuum (SC) sources reaching far into the infrared (IR) have emerged with the potential to rival traditional broadband sources of IR radiation. Here, the brightness of these IR SC sources is compared with that of synchrotron IR beamlines and SiC thermal emitters (Globars). It is found that SC sources can deliver a brightness that is 5-6 orders of magnitude higher than Globars and 1-2 orders of magnitude higher than typical IR beamlines, matching the beamlines at least out to 10.6 μm (940 cm-1). This means that these sources can now cover nearly all of the 800-5000 cm-1 spectrum (2-12.5 μm) which is frequently used in IR spectroscopy and microscopy. To demonstrate applicability, such an IR SC source was used for transmission spectroscopy of highly scattering filtration membranes from 3500 to 1300 cm-1, and transmission microscopy of colon tissue at 1538 cm-1.

Three-dimensional monochromatic x-ray computed tomography using synchrotron radiation

NASA Astrophysics Data System (ADS)

Saito, Tsuneo; Kudo, Hiroyuki; Takeda, Tohoru; Itai, Yuji; Tokumori, Kenji; Toyofuku, Fukai; Hyodo, Kazuyuki; Ando, Masami; Nishimura, Katsuyuki; Uyama, Chikao

1998-08-01

We describe a technique of 3D computed tomography (3D CT) using monochromatic x rays generated by synchrotron radiation, which performs a direct reconstruction of a 3D volume image of an object from its cone-beam projections. For the development, we propose a practical scanning orbit of the x-ray source to obtain complete 3D information on an object, and its corresponding 3D image reconstruction algorithm. The validity and usefulness of the proposed scanning orbit and reconstruction algorithm were confirmed by computer simulation studies. Based on these investigations, we have developed a prototype 3D monochromatic x-ray CT using synchrotron radiation, which provides exact 3D reconstruction and material-selective imaging by using the K-edge energy subtraction technique.

Real Time In Situ Observations of Equiaxed Dendrite Coherency in Al-Cu Alloys Using High-Brilliance, 3rd Generation Synchrotron Sources

NASA Technical Reports Server (NTRS)

Murphy, Andrew G.; Browne, David J.; Mirihanage, Wajira U.; Mathiesen, Ragnvald H.

2012-01-01

In the last decade synchrotron X-ray sources have fast become the tool of choice for performing in-situ high resolution imaging during alloy solidification. This paper presents the results of an experimental campaign carried out at the European Synchrotron Radiation Facility, using a Bridgman furnace, to monitor phenomena during solidification of Al-Cu alloys - specifically the onset of equiaxed dendrite coherency. Conventional experimental methods for determining coherency involve measuring the change in viscosity or measuring the change in thermal conductivity across the solidifying melt Conflicts arise when comparing the results of these experimental techniques to find a relationship between cooling rate and coherency fraction. It has been shown that the ratio of average velocity to the average grain diameter has an inversely proportional relationship to coherency fraction. In-situ observation therefore makes it possible to measure these values directly from acquired images sequences and make comparisons with published results.

Observing microscopic structures of a relativistic object using a time-stretch strategy.

PubMed

Roussel, E; Evain, C; Le Parquier, M; Szwaj, C; Bielawski, S; Manceron, L; Brubach, J-B; Tordeux, M-A; Ricaud, J-P; Cassinari, L; Labat, M; Couprie, M-E; Roy, P

2015-05-28

Emission of light by a single electron moving on a curved trajectory (synchrotron radiation) is one of the most well-known fundamental radiation phenomena. However experimental situations are more complex as they involve many electrons, each being exposed to the radiation of its neighbors. This interaction has dramatic consequences, one of the most spectacular being the spontaneous formation of spatial structures inside electrons bunches. This fundamental effect is actively studied as it represents one of the most fundamental limitations in electron accelerators, and at the same time a source of intense terahertz radiation (Coherent Synchrotron Radiation, or CSR). Here we demonstrate the possibility to directly observe the electron bunch microstructures with subpicosecond resolution, in a storage ring accelerator. The principle is to monitor the terahertz pulses emitted by the structures, using a strategy from photonics, time-stretch, consisting in slowing-down the phenomena before recording. This opens the way to unpreceeded possibilities for analyzing and mastering new generation high power coherent synchrotron sources.

Observing microscopic structures of a relativistic object using a time-stretch strategy

NASA Astrophysics Data System (ADS)

Roussel, E.; Evain, C.; Le Parquier, M.; Szwaj, C.; Bielawski, S.; Manceron, L.; Brubach, J.-B.; Tordeux, M.-A.; Ricaud, J.-P.; Cassinari, L.; Labat, M.; Couprie, M.-E.; Roy, P.

2015-05-01

Emission of light by a single electron moving on a curved trajectory (synchrotron radiation) is one of the most well-known fundamental radiation phenomena. However experimental situations are more complex as they involve many electrons, each being exposed to the radiation of its neighbors. This interaction has dramatic consequences, one of the most spectacular being the spontaneous formation of spatial structures inside electrons bunches. This fundamental effect is actively studied as it represents one of the most fundamental limitations in electron accelerators, and at the same time a source of intense terahertz radiation (Coherent Synchrotron Radiation, or CSR). Here we demonstrate the possibility to directly observe the electron bunch microstructures with subpicosecond resolution, in a storage ring accelerator. The principle is to monitor the terahertz pulses emitted by the structures, using a strategy from photonics, time-stretch, consisting in slowing-down the phenomena before recording. This opens the way to unpreceeded possibilities for analyzing and mastering new generation high power coherent synchrotron sources.

A new XUV optical end-station to characterize compact and flexible photonic devices using synchrotron radiation

NASA Astrophysics Data System (ADS)

Marcelli, A.; Mazuritskiy, M. I.; Dabagov, S. B.; Hampai, D.; Lerer, A. M.; Izotova, E. A.; D'Elia, A.; Turchini, S.; Zema, N.; Zuccaro, F.; de Simone, M.; Javad Rezvani, S.; Coreno, M.

2018-03-01

In this contribution we present the new experimental end-station to characterize XUV diffractive optics, such as Micro Channel Plates (MCPs) and other polycapillary optics, presently under commission at the Elettra synchrotron radiation laboratory (Trieste, Italy). To show the opportunities offered by these new optical devices for 3rd and 4th generation radiation sources, in this work we present also some patterns collected at different energies of the primary XUV radiation transmitted by MCP optical devices working in the normal incidence geometry.

GeoSoilEnviroCARS: A National User Facility for Synchrotron Radiation Research

NASA Astrophysics Data System (ADS)

Rivers, M. L.; Sutton, S. R.

2002-12-01

GeoSoilEnviroCARS (GSECARS) is a national user facility for frontier research in the earth sciences using synchrotron radiation at the Advanced Photon Source, Argonne National Laboratory. GSECARS provides earth scientists with access to the high-brilliance hard x-rays from this third-generation synchrotron light source. Both an undulator and a bending magnet beamline are available. All principal synchrotron-based analytical techniques in demand by earth scientists are being brought to bear on earth science problems: (1) high-pressure/high-temperature crystallography and spectroscopy using the diamond anvil cell; (2) high-pressure/high-temperature crystallography using the large-volume press; (3) powder, single crystal and interface diffraction; (4) inelastic x-ray scattering; (5) x-ray absorption fine structure (XAFS) spectroscopy; (6) x-ray fluorescence microprobe analysis; and (7) microtomography. The major instrumentation includes 250 and 1000 MN multianvil presses, a double-sided laser heating system, a large general-purpose 5-circle diffractometer, a focused microprobe, and a Raman laboratory. A proposal-based system for beamtime allocation, open to all earth scientists, has been in place since Fall, 1998. Since then, over 450 beamtime proposals have been received and more than 320 outside users have conducted experiments at GSECARS. The research conducted by these investigators has resulted in more than 170 publications. The unique capabilities of the APS and GSECARS have allowed groundbreaking experiments to be conducted. These include: (1) phase transformations in the Mg-Si-O system at mantle conditions; (2) structure of hydrated a-Al2O3 surfaces; (3) alloying properties of silicon in the Earth's core; (4) dynamics of iron-rich melt segregation from silicates during core formation; (5) electronic spin state of FeO at high pressure and temperature; (6) elastic wave velocities of mantle minerals at lower mantle conditions; (7) copper partitioning and speciation in natural hydrothermal fluids; and (8) mechanisms of arsenic sequestration at a Superfund site. The GSECARS mission is to provide a research environment where users receive expert assistance in planning and conducting experiments, and in analyzing data. The facility operation is funded by the NSF EAR Instrumentation and Facilities program and the DOE Geosciences program. Major instrumentation was also provided by the W.M. Keck Foundation. Information and applications for beam time can be found at http://gsecars.org.

Mono-Energy Coronary Angiography with a Compact Synchrotron Source

NASA Astrophysics Data System (ADS)

Eggl, Elena; Mechlem, Korbinian; Braig, Eva; Kulpe, Stephanie; Dierolf, Martin; Günther, Benedikt; Achterhold, Klaus; Herzen, Julia; Gleich, Bernhard; Rummeny, Ernst; Noёl, Peter B.; Pfeiffer, Franz; Muenzel, Daniela

2017-02-01

X-ray coronary angiography is an invaluable tool for the diagnosis of coronary artery disease. However, the use of iodine-based contrast media can be contraindicated for patients who present with chronic renal insufficiency or with severe iodine allergy. These patients could benefit from a reduced contrast agent concentration, possibly achieved through application of a mono-energetic x-ray beam. While large-scale synchrotrons are impractical for daily clinical use, the technology of compact synchrotron sources strongly advanced during the last decade. Here we present a quantitative analysis of the benefits a compact synchrotron source can offer in coronary angiography. Simulated projection data from quasi-mono-energetic and conventional x-ray tube spectra is used for a CNR comparison. Results show that compact synchrotron spectra would allow for a significant reduction of contrast media. Experimentally, we demonstrate the feasibility of coronary angiography at the Munich Compact Light Source, the first commercial installation of a compact synchrotron source.

SPring-8 beamline control system.

PubMed

Ohata, T; Konishi, H; Kimura, H; Furukawa, Y; Tamasaku, K; Nakatani, T; Tanabe, T; Matsumoto, N; Ishii, M; Ishikawa, T

1998-05-01

The SPring-8 beamline control system is now taking part in the control of the insertion device (ID), front end, beam transportation channel and all interlock systems of the beamline: it will supply a highly standardized environment of apparatus control for collaborative researchers. In particular, ID operation is very important in a third-generation synchrotron light source facility. It is also very important to consider the security system because the ID is part of the storage ring and is therefore governed by the synchrotron ring control system. The progress of computer networking systems and the technology of security control require the development of a highly flexible control system. An interlock system that is independent of the control system has increased the reliability. For the beamline control system the so-called standard model concept has been adopted. VME-bus (VME) is used as the front-end control system and a UNIX workstation as the operator console. CPU boards of the VME-bus are RISC processor-based board computers operated by a LynxOS-based HP-RT real-time operating system. The workstation and the VME are linked to each other by a network, and form the distributed system. The HP 9000/700 series with HP-UX and the HP 9000/743rt series with HP-RT are used. All the controllable apparatus may be operated from any workstation.

Protein Data Bank depositions from synchrotron sources.

PubMed

Jiang, Jiansheng; Sweet, Robert M

2004-07-01

A survey and analysis of Protein Data Bank (PDB) depositions from international synchrotron radiation facilities, based on the latest released PDB entries, are reported. The results (http://asdp.bnl.gov/asda/Libraries/) show that worldwide, every year since 1999, more than 50% of the deposited X-ray structures have used synchrotron facilities, reaching 75% by 2003. In this web-based database, all PDB entries among individual synchrotron beamlines are archived, synchronized with the weekly PDB release. Statistics regarding the quality of experimental data and the refined model for all structures are presented, and these are analysed to reflect the impact of synchrotron sources. The results confirm the common impression that synchrotron sources extend the size of structures that can be solved with equivalent or better quality than home sources.

The uses of synchrotron radiation sources for elemental and chemical microanalysis

USGS Publications Warehouse

Chen, J.R.; Chao, E.C.T.; Minkin, J.A.; Back, J.M.; Jones, K.W.; Rivers, M.L.; Sutton, S.R.

1990-01-01

Synchrotron radiation sources offer important features for the analysis of a material. Among these features is the ability to determine both the elemental composition of the material and the chemical state of its elements. For microscopic analysis synchrotron X-ray fluorescence (SXRF) microprobes now offer spatial resolutions of 10 ??m with minimum detection limits in the 1-10 ppm range depending on the nature of the sample and the synchrotron source used. This paper describes the properties of synchrotron radiation and their importance for elemental analysis, existing synchrotron facilities and those under construction that are optimum for SXRF microanalysis, and a number of applications including the high energy excitation of the K lines of heavy elements, microtomography, and XANES and EXAFS spectroscopies. ?? 1990.

NSLS-II beamline scattered gas bremsstrahlung radiation shielding calculation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Popescu, Razvan; Xia, Zhenghua, E-mail: xiazhenghuacn@hotmail.com; Job, Panakkal

2016-07-27

National Synchrotron Light Source II (NSLS-II) is a new state-of-the-art 3rd generation synchrotron. The NSLS-II facility is shielded up to 3 GeV electron beam energy at 500 mA. When the gas bremsstrahlung (GB) from the storage ring is scattered by the beamline components in the first optical enclosure (FOE), the scattered radiation will pose additional radiation hazard (bypassing primary GB collimators and stops) and challenge the FOE shielding. The scattered GB radiation hazard can be mitigated by supplementary shielding or with an exclusion zone downstream of the FOE.

SESAME - A 3rd Generation Synchrotron Light Source for the Middle East

NASA Astrophysics Data System (ADS)

U˝Lkü, Dinçer; Rahighi, Javad; Winick, Herman

2007-01-01

SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK, and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference ~133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member countries. Additional funds to purchase components of the new ring and beamlines are being sought from the EU, the US, and other sources. SESAME has benefited greatly from offers by other light source facilities of equipment and training fellowships in both accelerator technology and applications of synchrotron radiation. Details of this, and other aspects of the training program, are given below. It is hoped that in the future fellowship offers will continue to be made by many light source laboratories to further increase the level of experience with accelerator technology and synchrotron light science in preparation for the start of operation of SESAME.

SESAME — A 3rd Generation Synchrotron Light Source for the Middle East

NASA Astrophysics Data System (ADS)

Å°lkü, Dinçer; Rahighi, Javad; Winick, Herman

2007-01-01

SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK, and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference ˜133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member countries. Additional funds to purchase components of the new ring and beamlines are being sought from the EU, the US, and other sources. SESAME has benefited greatly from offers by other light source facilities of equipment and training fellowships in both accelerator technology and applications of synchrotron radiation. Details of this, and other aspects of the training program, are given below. It is hoped that in the future fellowship offers will continue to be made by many light source laboratories to further increase the level of experience with accelerator technology and synchrotron light science in preparation for the start of operation of SESAME.

SESAME - A 3rd Generation Synchrotron Light Source for the Middle East

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ulkue, Dincer; Rahighi, Javad; Winick, Herman

2007-01-19

SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK,more » and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference {approx}133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member countries. Additional funds to purchase components of the new ring and beamlines are being sought from the EU, the US, and other sources. SESAME has benefited greatly from offers by other light source facilities of equipment and training fellowships in both accelerator technology and applications of synchrotron radiation. Details of this, and other aspects of the training program, are given below. It is hoped that in the future fellowship offers will continue to be made by many light source laboratories to further increase the level of experience with accelerator technology and synchrotron light science in preparation for the start of operation of SESAME.« less

Stanford Synchrotron Radiation Laboratory activity report for 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cantwell, K.

1987-12-31

1986 was another year of major advances for SSRL as the ultimate capabilities of PEP as a synchrotron radiation source became more apparent and a second PEP beam line was initiated, while effective development and utilization of SPEAR proceeded. Given these various PEP developments, SSRL abandoned its plans for a separate diffraction limited ring, as they abandoned their plans for a 6--7 GeV ring of the APS type last year. It has become increasingly apparent that SSRL should concentrate on developing SPEAR and PEP as synchrotron radiation sources. Consequently, initial planning for a 3 GeV booster synchrotron injector for SPEARmore » was performed in 1986, with a proposal to the Department of Energy resulting. As described in Chapter 2, the New Rings Group and the Machine Physics Group were combined into one Accelerator Physics Group. This group is focusing mainly on the improvement of SPEAR`s operating conditions and on planning for the conversion of PEP into a fourth generation x-ray source. Considerable emphasis is also being given to the training of accelerator physics graduate students. At the same time, several improvements of SSRL`s existing facilities were made. These are described in Chapter 3. Chapter 4 describes new SSRL beam lines being commissioned. Chapter 5 discusses SSRL`s present construction projects. Chapter 6 discusses a number of projects presently underway in the engineering division. Chapter 7 describes SSRL`s advisory panels while Chapter 8 discusses SSRL`s overall organization. Chapter 9 describes the experimental progress reports.« less

Imaging of cochlear tissue with a grating interferometer and hard X-rays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richter, Claus-Peter; Shintani-Smith, Stephanie; Fishman, Andrew

This article addresses an important current development in medical and biological imaging: the possibility of imaging soft tissue at resolutions in the micron range using hard X-rays. Challenging environments, including the cochlea, require the imaging of soft tissue structure surrounded by bone. We demonstrate that cochlear soft tissue structures can be imaged with hard X-ray phase contrast. Furthermore, we show that only a thin slice of the tissue is required to introduce a large phase shift. It is likely that the phase contrast image of the soft tissue structures is sufficient to image the structures even if surrounded by bone.more » For the present set of experiments, structures with low-absorption contrast have been visualized using in-line phase contrast imaging and a grating interferometer. The experiments have been performed at the Advanced Photon Source at Argonne National Laboratories, a third generation source of synchrotron radiation. The source provides highly coherent X-ray radiation with high-photon flux (>10{sup 12} photons/s) at high-photon energies (5-70 keV). Radiographic and light microscopy images of the gerbil cochlear slice samples were compared. It has been determined that a 20-{micro}m thick tissue slice induces a phase shift between 1/3{pi} and 2/3{pi}.« less

Compact laser accelerators for X-ray phase-contrast imaging

PubMed Central

Najmudin, Z.; Kneip, S.; Bloom, M. S.; Mangles, S. P. D.; Chekhlov, O.; Dangor, A. E.; Döpp, A.; Ertel, K.; Hawkes, S. J.; Holloway, J.; Hooker, C. J.; Jiang, J.; Lopes, N. C.; Nakamura, H.; Norreys, P. A.; Rajeev, P. P.; Russo, C.; Streeter, M. J. V.; Symes, D. R.; Wing, M.

2014-01-01

Advances in X-ray imaging techniques have been driven by advances in novel X-ray sources. The latest fourth-generation X-ray sources can boast large photon fluxes at unprecedented brightness. However, the large size of these facilities means that these sources are not available for everyday applications. With advances in laser plasma acceleration, electron beams can now be generated at energies comparable to those used in light sources, but in university-sized laboratories. By making use of the strong transverse focusing of plasma accelerators, bright sources of betatron radiation have been produced. Here, we demonstrate phase-contrast imaging of a biological sample for the first time by radiation generated by GeV electron beams produced by a laser accelerator. The work was performed using a greater than 300 TW laser, which allowed the energy of the synchrotron source to be extended to the 10–100 keV range. PMID:24470414

High-throughput Crystallography for Structural Genomics

PubMed Central

Joachimiak, Andrzej

2009-01-01

Protein X-ray crystallography recently celebrated its 50th anniversary. The structures of myoglobin and hemoglobin determined by Kendrew and Perutz provided the first glimpses into the complex protein architecture and chemistry. Since then, the field of structural molecular biology has experienced extraordinary progress and now over 53,000 proteins structures have been deposited into the Protein Data Bank. In the past decade many advances in macromolecular crystallography have been driven by world-wide structural genomics efforts. This was made possible because of third-generation synchrotron sources, structure phasing approaches using anomalous signal and cryo-crystallography. Complementary progress in molecular biology, proteomics, hardware and software for crystallographic data collection, structure determination and refinement, computer science, databases, robotics and automation improved and accelerated many processes. These advancements provide the robust foundation for structural molecular biology and assure strong contribution to science in the future. In this report we focus mainly on reviewing structural genomics high-throughput X-ray crystallography technologies and their impact. PMID:19765976

Watching proteins function with time-resolved x-ray crystallography

NASA Astrophysics Data System (ADS)

Šrajer, Vukica; Schmidt, Marius

2017-09-01

Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115-54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201-41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651-9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237-51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5-20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242-6, Barends et al 2015 Science 350 445-50, Pande et al 2016 Science 352 725-9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline challenges and further developments necessary to broaden the application of these methods to many important proteins and enzymes of biomedical relevance.

Watching proteins function with time-resolved x-ray crystallography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Šrajer, Vukica; Schmidt, Marius

Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in actionmore » and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline challenges and further developments necessary to broaden the application of these methods to many important proteins and enzymes of biomedical relevance.« less

Defect generation in silicon dioxide from synchrotron radiation below 41 eV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, C. K.; Reisman, A.; Bhattacharya, P.

1989-07-01

Generation of fixed positive charge, neutral electron traps, and fixednegative charge in SiO/sub 2/ due to exposure to x radiation in the photon energyrange below 41 eV from a synchrotron source is reported. For constant incidentx-radiation exposure levels of 120 mJ/cm/sup 2/ with both monochromatic andbroadband radiation, the number of defects generated in the monitoring deviceswas at or below the detection limit of the equipment. This is in sharp contrastwith the results obtained at photon energies above 300 eV reported earlier (C.K. Williams, A. Reisman, P. K. Bhattacharya, and W. Ng, J. Appl. Phys./bold 64/, 1145 (1988)) in which amore » large number of each of the three defectsmentioned above were generated. The lack of damage indicates that the problemsassociated with x-ray-induced insulator damage due to x-ray lithography may besolved by tailoring the photon energy, provided suitable mask and photoresistmaterials can be developed.« less

Ultraviolet Free Electron Laser Facility preliminary design report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ben-Zvi, I.

1993-02-01

This document, the Preliminary Design Report (PDR) for the Brookhaven Ultraviolet Free Electron Laser (UV FEL) facility, describes all the elements of a facility proposed to meet the needs of a research community which requires ultraviolet sources not currently available as laboratory based lasers. Further, for these experiments, the requisite properties are not extant in either the existing second or upcoming third generation synchrotron light sources. This document is the result of our effort at BNL to identify potential users, determine the requirements of their experiments, and to design a facility which can not only satisfy the existing need, butmore » have adequate flexibility for possible future extensions as need dictates and as evolving technology allows. The PDR is comprised of three volumes. In this, the first volume, background for the development of the proposal is given, including descriptions of the UV FEL facility, and representative examples of the science it was designed to perform. Discussion of the limitations and potential directions for growth are also included. A detailed description of the facility design is then provided, which addresses the accelerator, optical, and experimental systems. Information regarding the conventional construction for the facility is contained in an addendum to volume one (IA).« less

Brazing copper to dispersion-strengthened copper

NASA Astrophysics Data System (ADS)

Ryding, David G.; Allen, Douglas; Lee, Richard H.

1996-11-01

The advanced photon source is a state-of-the-art synchrotron light source that will produce intense x-ray beams, which will allow the study of smaller samples and faster reactions and processes at a greater level of detail than has ben possible to date. The beam is produced by using third- generation insertion devices in a 7-GeV electron/positron storage ring that is 1,104 meters in circumference. The heat load from these intense high-power devices is very high, and certain components must sustain total heat loads of 3 to 15 kW and heat fluxes of 30 W/mm$_2). Because the beams will cycle on and off many times, thermal shock and fatigue will be a problem. High heat flux impinging on a small area causes a large thermal gradient that results in high stress. GlidCop, a dispersion-strengthened copper, is the desired design material because of its high thermal conductivity and superior mechanical properties as compared to copper and its alloys. GlidCop is not amenable to joining by fusion welding, and brazing requires diligence because of high diffusivity. Brazing procedures were developed using optical and scanning electron microscopy.

Synchrotron light sources in developing countries

DOE PAGES

Mtingwa, Sekazi K.; Winick, Herman

2018-03-21

Here, we discuss the role that synchrotron light sources, such as SESAME, could play in improving the socioeconomic conditions in developing countries. After providing a brief description of a synchrotron light source, we discuss the important role that they played in the development of several economically emerging countries. Then we describe the state of synchrotron science in South Africa and that country’s leadership role in founding the African Light Source initiative. Next, we highlight a new initiative called Lightsources for Africa, the Americas & Middle East Project, which is a global initiative led by the International Union of Pure andmore » Applied Physics and the International Union of Crystallography, with initial funding provided by the International Council for Science. Finally, we comment on a new technology called the multibend achromat that has launched a new paradigm for the design of synchrotron light sources that should be attractive for construction in developing countries.« less

Synchrotron light sources in developing countries

NASA Astrophysics Data System (ADS)

Mtingwa, Sekazi K.; Winick, Herman

2018-03-01

We discuss the role that synchrotron light sources, such as SESAME, could play in improving the socioeconomic conditions in developing countries. After providing a brief description of a synchrotron light source, we discuss the important role that they played in the development of several economically emerging countries. Then we describe the state of synchrotron science in South Africa and that country’s leadership role in founding the African Light Source initiative. Next, we highlight a new initiative called Lightsources for Africa, the Americas & Middle East Project, which is a global initiative led by the International Union of Pure and Applied Physics and the International Union of Crystallography, with initial funding provided by the International Council for Science. Finally, we comment on a new technology called the multibend achromat that has launched a new paradigm for the design of synchrotron light sources that should be attractive for construction in developing countries.

Synchrotron light sources in developing countries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mtingwa, Sekazi K.; Winick, Herman

Here, we discuss the role that synchrotron light sources, such as SESAME, could play in improving the socioeconomic conditions in developing countries. After providing a brief description of a synchrotron light source, we discuss the important role that they played in the development of several economically emerging countries. Then we describe the state of synchrotron science in South Africa and that country’s leadership role in founding the African Light Source initiative. Next, we highlight a new initiative called Lightsources for Africa, the Americas & Middle East Project, which is a global initiative led by the International Union of Pure andmore » Applied Physics and the International Union of Crystallography, with initial funding provided by the International Council for Science. Finally, we comment on a new technology called the multibend achromat that has launched a new paradigm for the design of synchrotron light sources that should be attractive for construction in developing countries.« less

Photoexcitation and photoionization of argon atom and chlorine molecule using the Advanced Light Source

NASA Astrophysics Data System (ADS)

Nayandin, Oleg

2001-08-01

The use of a third generation Synchrotron Radiation source combined with time-of-flight (TOF) electron spectrometers and a two-dimensional (2D) imaging technique makes it possible to investigate and reveal new aspects of atomic and molecular structure, and allows a better understanding of electron correlation. This dissertation concentrates on the experimental study of the interaction of synchrotron radiation with argon atoms and chlorine molecules in the gas phase. The measurements were performed using a two-dimensional photoelectron spectroscopy technique in combination with the high resolution Atomic, Molecular and Optical Physics undulator beam line at the Advanced Light Source at the Lawrence Berkeley National Laboratory. The complete angle-resolved 2D experimental images of the electron emission following photoexcitation and photoionization of the 2p inner-shell in Ar and Cl2 were measured. For argon, the intensity profiles as a function of photon energy for all accessible Auger decay channels were studied for the first time. Significant asymmetries are observed in these various partial cross-sections, due to the interference between direct photoionization and resonant photoexcitation leading to the same final ionic state. For chlorine, Auger electron spectra following the decay of the 2p --> σ* and 2p --> nl resonances were analyzed. It was found that valence photoionization channels do not resonate strongly for photon energies equal to the coreto-Rydberg excitation, in contrast to the strongly resonating ones observed in the HCl molecule. Auger decay spectra of the 2p-1σ* resonances showed no evidence of atomic transitions in Cl2, indicative of no significant dissociation, also in contrast to HCl. In addition, angular distributions of the photo- and Auger electron lines were derived. These results contribute to a better understanding of atomic and molecular structure and dynamics of inner shell processes and hopefully will stimulate further experimental and theoretical work.

Impact of synchrotron radiation on macromolecular crystallography: a personal view

PubMed Central

Dauter, Zbigniew; Jaskolski, Mariusz; Wlodawer, Alexander

2010-01-01

The introduction of synchrotron radiation sources almost four decades ago has led to a revolutionary change in the way that diffraction data from macromolecular crystals are being collected. Here a brief history of the development of methodologies that took advantage of the availability of synchrotron sources are presented, and some personal experiences with the utilization of synchrotrons in the early days are recalled. PMID:20567074

Synchrotron pair halo and echo emission from blazars in the cosmic web: application to extreme TeV blazars

NASA Astrophysics Data System (ADS)

Oikonomou, Foteini; Murase, Kohta; Kotera, Kumiko

2014-08-01

High frequency peaked, high redshift blazars, are extreme in the sense that their spectrum is particularly hard and peaks at TeV energies. Standard leptonic scenarios require peculiar source parameters and/or a special setup in order to account for these observations. Electromagnetic cascades seeded by ultra-high energy cosmic rays (UHECR) in the intergalactic medium have also been invoked, assuming a very low intergalactic magnetic field (IGMF). Here we study the synchrotron emission of UHECR secondaries produced in blazars located in magnetised environments, and show that it can provide an alternative explanation to these challenged channels, for sources embedded in structured regions with magnetic field strengths of the order of 10-7 G. To demonstrate this, we focus on three extreme blazars: 1ES 0229+200, RGB J0710+591, and 1ES 1218+304. We model the expected gamma-ray signal from these sources through a combination of numerical Monte Carlo simulations and solving the kinetic equations of the particles in our simulations, and explore the UHECR source and intergalactic medium parameter space to test the robustness of the emission. We show that the generated synchrotron-pair halo and echo flux at the peak energy is not sensitive to variations in the overall IGMF strength. This signal is unavoidable in contrast to the inverse Compton-pair halo and echo intensity, which is appealing in view of the large uncertainties on the IGMF in voids of large scale structure. It is also shown that the variability of blazar gamma-ray emission can be accommodated by the synchrotron emission of secondary products of UHE neutral beams if these are emitted by UHECR accelerators inside magnetised regions.

Improved radiation dose efficiency in solution SAXS using a sheath flow sample environment

PubMed Central

Kirby, Nigel; Cowieson, Nathan; Hawley, Adrian M.; Mudie, Stephen T.; McGillivray, Duncan J.; Kusel, Michael; Samardzic-Boban, Vesna; Ryan, Timothy M.

2016-01-01

Radiation damage is a major limitation to synchrotron small-angle X-ray scattering analysis of biomacromolecules. Flowing the sample during exposure helps to reduce the problem, but its effectiveness in the laminar-flow regime is limited by slow flow velocity at the walls of sample cells. To overcome this limitation, the coflow method was developed, where the sample flows through the centre of its cell surrounded by a flow of matched buffer. The method permits an order-of-magnitude increase of X-ray incident flux before sample damage, improves measurement statistics and maintains low sample concentration limits. The method also efficiently handles sample volumes of a few microlitres, can increase sample throughput, is intrinsically resistant to capillary fouling by sample and is suited to static samples and size-exclusion chromatography applications. The method unlocks further potential of third-generation synchrotron beamlines to facilitate new and challenging applications in solution scattering. PMID:27917826

Updates on the African Synchrotron Light Source (AfLS) Project

NASA Astrophysics Data System (ADS)

Dobbins, Tabbetha; Mtingwa, Sekazi; Wague, Ahmadou; Connell, Simon; Masara, Brian; Ntsoane, Tshepo; Norris, Lawrence; Winick, Herman; Evans-Lutterodt, Kenneth; Hussein, Tarek; Maresha, Feene; McLaughlin, Krystle; Oladijo, Philip; Du Plessis, Esna; Murenzi, Romain; Reed, Kennedy; Sette, Francesco; Werin, Sverker; Dorfan, Jonathan; Yousef, Mohammad

Africa is the only habitable continent without a synchrotron light source. A full steering committee was elected at the African Light Source (AfLS) conference on November 16-20, 2015 at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The conference brought together African scientists, policy makers, and stakeholders to discuss a synchrotron light source in Africa. Firm outcomes of the Conference were a set of resolutions and a roadmap. Additionally, a collaborative proposal to promote Advanced Light Sources and crystallographic sciences in targeted regions of the world was submitted by the International Union of Pure and Applied Physics (IUPAP) and the International Union of Crystallography (IUCr) to the International Council for Science (ICSU). www.africanlightsource.org.

TeV electron measurement with CREST experiment

NASA Astrophysics Data System (ADS)

Park, Nahee; Anderson, T.; Bower, C.; Coutu, S.; Gennaro, J.; Geske, M.; Muller, D.; Musser, J.; Nutter, S.

CREST, the Cosmic Ray Electron Synchrotron Telescope is a balloon-borne experiment de-signed to measure the spectrum of multi-TeV electrons by the detection of the x-ray synchrotron photons generated in the magnetic field of the Earth. Electrons in the TeV range are expected to reflect the properties of local sources because fluxes from remote locations are suppressed by radiative losses during propagation. Since CREST needs to intersect only a portion of the kilometers-long trail of photons generated by the high-energy electron, the method yields a larger effective area than the physical size of the detector, boosting detection areas. The in-strument is composed of an array of 1024 BaF2 crystals and a set of scintillating veto counters. A long duration balloon flight in Antarctica is currently planned for the 2010-11 season.

NSLS II Vacuum System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ferreira, M.; Doom, L.; Hseuh, H.

2009-09-13

National Synchrotron Light Source II, being constructed at Brookhaven, is a 3-GeV, 500 mA, 3rd generation synchrotron radiation facility with ultra low emittance electron beams. The storage ring vacuum system has a circumference of 792 m and consists of over 250 vacuum chambers with a simulated average operating pressure of less than 1 x 10{sup -9} mbar. A summary of the update design of the vacuum system including girder supports of the chambers, gauges, vacuum pumps, bellows, beam position monitors and simulation of the average pressure will be shown. A brief description of the techniques and procedures for cleaning andmore » mounting the chambers are given.« less

Some aspects of cosmic synchrotron sources

NASA Technical Reports Server (NTRS)

Epstein, R. I.

1973-01-01

Synchrotron emission is considered from individual particles which have small pitch angles and the general properties of synchrotron sources which mainly contain such particles, as well as the emissivities and degrees of circular polarization for specific source distributions. The limitation of synchrotron source models for optical pulsars and compact extragalactic objects are discussed, and it is shown that several existing models for the pulsar NP 0532 are inconsistent with the measured time variations and polarizations of the optical emission. Discussion is made also of whether the low frequency falloffs in the extragalactic objects PKS 2134 + 004, OQ 208, and NGC 1068 is due to emission from particles with small pitch angles or absorption by a thermal plasma or synchrotron self-absorption. It is concluded that the absorption interpretations cannot account for the turnover in the spectrum of PKS 2134 + 004. Measurements of polarization, angular structure, and X-ray flux are also described.

Design of Synchrotron Light Source in Taiwan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuo, C. C.; Chang, H. P.; Chou, P. J.

2007-01-19

An intermediate energy synchrotron light source has been proposed. The goal is to construct a high performance light source in complementary to the existing 1.5 GeV synchrotron ring in Taiwan to boost the research capabilities. A 3 GeV machine with 518.4 m and 24-cell DBA lattice structure is considered and other options are also investigated. We report the 24-cell design considerations and its performances.

Cracking evolution behaviors of lightweight materials based on in situ synchrotron X-ray tomography: A review

NASA Astrophysics Data System (ADS)

Luo, Y.; Wu, S. C.; Hu, Y. N.; Fu, Y. N.

2018-03-01

Damage accumulation and failure behaviors are crucial concerns during the design and service of a critical component, leading researchers and engineers to thoroughly identifying the crack evolution. Third-generation synchrotron radiation X-ray computed microtomography can be used to detect the inner damage evolution of a large-density material or component. This paper provides a brief review of studying the crack initiation and propagation inside lightweight materials with advanced synchrotron three-dimensional (3D) X-ray imaging, such as aluminum materials. Various damage modes under both static and dynamic loading are elucidated for pure aluminum, aluminum alloy matrix, aluminum alloy metal matrix composite, and aluminum alloy welded joint. For aluminum alloy matrix, metallurgical defects (porosity, void, inclusion, precipitate, etc.) or artificial defects (notch, scratch, pit, etc.) strongly affect the crack initiation and propagation. For aluminum alloy metal matrix composites, the fracture occurs either from the particle debonding or voids at the particle/matrix interface, and the void evolution is closely related with fatigued cycles. For the hybrid laser welded aluminum alloy, fatigue cracks usually initiate from gas pores located at the surface or sub-surface and gradually propagate to a quarter ellipse or a typical semi-ellipse profile.

Speckle-based portable device for in-situ metrology of x-ray mirrors at Diamond Light Source

NASA Astrophysics Data System (ADS)

Wang, Hongchang; Kashyap, Yogesh; Zhou, Tunhe; Sawhney, Kawal

2017-09-01

For modern synchrotron light sources, the push toward diffraction-limited and coherence-preserved beams demands accurate metrology on X-ray optics. Moreover, it is important to perform in-situ characterization and optimization of X-ray mirrors since their ultimate performance is critically dependent on the working conditions. Therefore, it is highly desirable to develop a portable metrology device, which can be easily implemented on a range of beamlines for in-situ metrology. An X-ray speckle-based portable device for in-situ metrology of synchrotron X-ray mirrors has been developed at Diamond Light Source. Ultra-high angular sensitivity is achieved by scanning the speckle generator in the X-ray beam. In addition to the compact setup and ease of implementation, a user-friendly graphical user interface has been developed to ensure that characterization and alignment of X-ray mirrors is simple and fast. The functionality and feasibility of this device is presented with representative examples.

Single-pass high harmonic generation at high repetition rate and photon flux

NASA Astrophysics Data System (ADS)

Hädrich, Steffen; Rothhardt, Jan; Krebs, Manuel; Demmler, Stefan; Klenke, Arno; Tünnermann, Andreas; Limpert, Jens

2016-09-01

Sources of short wavelength radiation with femtosecond to attosecond pulse durations, such as synchrotrons or free electron lasers, have already made possible numerous, and will facilitate more, seminal studies aimed at understanding atomic and molecular processes on fundamental length and time scales. Table-top sources of coherent extreme ultraviolet to soft x-ray radiation enabled by high harmonic generation (HHG) of ultrashort pulse lasers have also gained significant attention in the last few years due to their enormous potential for addressing a plethora of applications, therefore constituting a complementary source to large-scale facilities (synchrotrons and free electron lasers). Ti:sapphire based laser systems have been the workhorses for HHG for decades, but are limited in repetition rate and average power. On the other hand, it has been widely recognized that fostering applications in fields such as photoelectron spectroscopy and microscopy, coincidence detection, coherent diffractive imaging and frequency metrology requires a high repetition rate and high photon flux HHG sources. In this article we will review recent developments in realizing the demanding requirement of producing a high photon flux and repetition rate at the same time. Particular emphasis will be put on suitable ultrashort pulse and high average power lasers, which directly drive harmonic generation without the need for external enhancement cavities. To this end we describe two complementary schemes that have been successfully employed for high power fiber lasers, i.e. optical parametric chirped pulse amplifiers and nonlinear pulse compression. Moreover, the issue of phase-matching in tight focusing geometries will be discussed and connected to recent experiments. We will highlight the latest results in fiber laser driven high harmonic generation that currently produce the highest photon flux of all existing sources. In addition, we demonstrate the first promising applications and discuss the future direction and challenges of this new type of HHG source.

IDENTIFYING THE COGNITIVE AND VASCULAR EFFECTS OF AIR POLLUTION SOURCES AND MIXTURES IN THE FRAMINGHARN OFFSPRING AND THIRD GENERATION COHORTS

EPA Science Inventory

We will estimate health risks associated with short- and long-term exposure to individual air pollutants, sources and air pollution mixtures within the Framingham Offspring and Third Generation populations. We will address which individual and area-level factors, measuring vul...

Design Study of an MBA Lattice for the Advanced Photon Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Decker, Glenn

2014-11-02

Recent interest in ultra-low-emittance designs for storage-ring-based synchrotron light sources has spurred a focused design effort on a multi-bend achromat (MBA) storage ring replacement for the Advanced Photon Source (APS). The APS is relatively large (1104 m circumference) and, as such, an upgrade to a fourth-generation storage ring holds the potential for a two to three order of magnitude enhancement of X-ray brightness due to the approximate inverse cubic scaling of emittance with the number of dipole bend magnets.

Status of the SAGA Light Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaneyasu, T.; Takabayashi, Y.; Iwasaki, Y.

The SAGA Light Source (SAGA-LS) is a synchrotron radiation facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring that is 75.6 m in circumference. The SAGA-LS has been stably providing synchrotron radiation to users since it first started user operation in February 2006. Along with the user operation, various machine improvements have been made over the past years, including upgrading the injector linac control system, replacing a septum magnet and constructing a beam diagnostic system. In addition to these improvements, insertion devices have been developed and installed. An APPLE-II type variable polarization undulator was installedmore » in 2008. To address the demand from users for high-flux hard x-rays, a superconducting 4 T class wiggler is being developed. An experimental setup for generating MeV photons by laser Compton scattering is being constructed for beam monitoring and future user experiments.« less

PKS 2155-304 relativistically beamed synchrotron radiation from BL LAC object

NASA Technical Reports Server (NTRS)

Urry, C. M.; Mushotzky, R. F.

1981-01-01

The newly discovered BL Lacertae object, PKS 2155-304, was observed with the medium and high intensity energy detectors of the HEAO-1 A2 experiment. The variability by a factor of two in less than a day reported by Snyder, et al (1979) is confirmed. Two spectra, obtained a year apart, while the satellite was in scanning mode, are well fit by simple power laws with energy spectral index alpha sub 1 equals approximately 1.4. A third spectrum, of higher statistical quality, obtained while the satellite was pointed at its source, has has two components. An acceptable fit was obtained using a two power law model, with indices alpha sub 1 equals 2.0 (+1.2, -0.6) and alpha sub 2 equals -1.5 (+1.5, -2.3). An interpretation of the overall spectrum from radio through X-rays in terms of a synchrotron self-Compton model gives a good description of the data if allowance is made for relativistic beaming. Thus, from a consideration of the spectrum, combined with an estimate of the size of the source, the presence of jets is inferred without their observation.

Assessing noise sources at synchrotron infrared ports

PubMed Central

Lerch, Ph.; Dumas, P.; Schilcher, T.; Nadji, A.; Luedeke, A.; Hubert, N.; Cassinari, L.; Boege, M.; Denard, J.-C.; Stingelin, L.; Nadolski, L.; Garvey, T.; Albert, S.; Gough, Ch.; Quack, M.; Wambach, J.; Dehler, M.; Filhol, J.-M.

2012-01-01

Today, the vast majority of electron storage rings delivering synchrotron radiation for general user operation offer a dedicated infrared port. There is growing interest expressed by various scientific communities to exploit the mid-IR emission in microspectroscopy, as well as the far infrared (also called THz) range for spectroscopy. Compared with a thermal (laboratory-based source), IR synchrotron radiation sources offer enhanced brilliance of about two to three orders of magnitude in the mid-IR energy range, and enhanced flux and brilliance in the far-IR energy range. Synchrotron radiation also has a unique combination of a broad wavelength band together with a well defined time structure. Thermal sources (globar, mercury filament) have excellent stability. Because the sampling rate of a typical IR Fourier-transform spectroscopy experiment is in the kHz range (depending on the bandwidth of the detector), instabilities of various origins present in synchrotron radiation sources play a crucial role. Noise recordings at two different IR ports located at the Swiss Light Source and SOLEIL (France), under conditions relevant to real experiments, are discussed. The lowest electron beam fluctuations detectable in IR spectra have been quantified and are shown to be much smaller than what is routinely recorded by beam-position monitors. PMID:22186638

Milky Way scattering properties and intrinsic sizes of active galactic nuclei cores probed by very long baseline interferometry surveys of compact extragalactic radio sources

NASA Astrophysics Data System (ADS)

Pushkarev, A. B.; Kovalev, Y. Y.

2015-10-01

We have measured the angular sizes of radio cores of active galactic nuclei (AGNs) and analysed their sky distributions and frequency dependences to study synchrotron opacity in AGN jets and the strength of angular broadening in the interstellar medium. We have used archival very long baseline interferometry (VLBI) data of more than 3000 compact extragalactic radio sources observed at frequencies, ν, from 2 to 43 GHz to measure the observed angular size of VLBI cores. We have found a significant increase in the angular sizes of the extragalactic sources seen through the Galactic plane (|b| ≲ 10°) at 2, 5 and 8 GHz, about one-third of which show significant scattering. These sources are mainly detected in directions to the Galactic bar, the Cygnus region and a region with galactic longitudes 220° ≲ l ≲ 260° (the Fitzgerald window). The strength of interstellar scattering of the AGNs is found to correlate with the Galactic Hα intensity, free-electron density and Galactic rotation measure. The dependence of scattering strengths on source redshift is insignificant, suggesting that the dominant scattering screens are located in our Galaxy. The observed angular size of Sgr A* is found to be the largest among thousands of AGNs observed over the sky; we discuss possible reasons for this strange result. Excluding extragalactic radio sources with significant scattering, we find that the angular size of opaque cores in AGNs scales typically as ν-1, confirming predictions of a conical synchrotron jet model with equipartition.

Time-Resolved Macromolecular Crystallography at Modern X-Ray Sources.

PubMed

Schmidt, Marius

2017-01-01

Time-resolved macromolecular crystallography unifies protein structure determination with chemical kinetics. With the advent of fourth generation X-ray sources the time-resolution can be on the order of 10-40 fs, which opens the ultrafast time scale to structure determination. Fundamental motions and transitions associated with chemical reactions in proteins can now be observed. Moreover, new experimental approaches at synchrotrons allow for the straightforward investigation of all kind of reactions in biological macromolecules. Here, recent developments in the field are reviewed.

From the Blazar Sequence to the Blazar Envelope: Revisiting the Relativistic Jet Dichotomy in Radio-Loud AGN

NASA Technical Reports Server (NTRS)

Meyer, Eileen T.; Fossati, Giovanini; Georganopoulos, Markos; Lister, Matthew L.

2012-01-01

We revisit the concept of a blazar sequence that relates the synchrotron peak frequency (Vpeak) in blazars with synchrotron peak luminosity (Lpeak, in vLv) using a large sample of radio-loud AGN. We present observational evidence that the blazar sequence is formed from two populations in the synchrotron Vpeak - Lpeak plane, each forming an upper edge to an envelope of progressively misaligned blazars, and connecting to an adjacent group of radio galaxies having jets viewed at much larger angles to the line of sight. When binned by jet kinetic power (Lkin; as measured through a scaling relationship with extended radio power), we find that radio core dominance decreases with decreasing synchrotron Lpeak, revealing that sources in the envelope are generally more misaligned. We find population-based evidence of velocity gradients in jets at low kinetic powers (approximately 10(exp 42) - 10(exp 44.5) erg s(exp -1)), corresponding to FR I radio galaxies and most BL Lacs. These low jet power 'weak jet' sources, thought to exhibit radiatively inefficient accretion, are distinguished from the population of non-decelerating, low synchrotron-peaking (LSP) blazars and FR II radio galaxies ('strong' jets) which are thought to exhibit radiatively efficient accretion. The two-population interpretation explains the apparent contradiction of the existence of highly core-dominated, low-power blazars at both low and high synchrotron peak frequencies, and further implies that most intermediate synchrotron peak (ISP) sources are not intermediate in intrinsic jet power between LSP and high synchrotron-peaking (HSP) sources, but are more misaligned versions of HSP sources with similar jet powers.

National Synchrotron Light Source annual report 1988

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hulbert, S.; Lazarz, N.; Williams, G.

1988-01-01

This report discusses the experiment done at the National Synchrotron Light Source. Most experiments discussed involves the use of the x-ray beams to study physical properties of solid materials. (LSP)

Plane-grating flat-field soft x-ray spectrometer

NASA Astrophysics Data System (ADS)

Hague, C. F.; Underwood, J. H.; Avila, A.; Delaunay, R.; Ringuenet, H.; Marsi, M.; Sacchi, M.

2005-02-01

We describe a soft x-ray spectrometer covering the 120-800 eV range. It is intended for resonant inelastic x-ray scattering experiments performed at third generation synchrotron radiation (SR) facilities and has been developed with SOLEIL, the future French national SR source in mind. The Hettrick-Underwood principle is at the heart of the design using a combination of varied line-spacing plane grating and spherical-mirror to provide a flat-field image. It is slitless for optimum acceptance. This means the source size determines the resolving power. A spot size of ⩽5μm is planned at SOLEIL which, according to simulations, should ensure a resolving power ⩾1000 over the whole energy range. A 1024×1024 pixel charge-coupled device (CCD) with a 13μm×13μm pixel size is used. This is an improvement on the use of microchannel-plate detectors, both as concerns efficiency and spatial resolution. Additionally spectral line curvature is avoided by the use of a horizontal focusing mirror concentrating the beam in the nondispersing direction. It allows for readout using a binning mode to reduce the intrinsically large CCD readout noise. Preliminary results taken at beamlines at Elettra (Trieste) and at BESSY (Berlin) are presented.

Dynamic performance of the beam position monitor support at the SSRF.

PubMed

Wang, Xiao; Cao, Yun; Du, Hanwen; Yin, Lixin

2009-01-01

Electron beam stability is very important for third-generation light sources, especially for the Shanghai Synchrotron Radiation Facility whose ground vibrations are much larger than those for other light sources. Beam position monitors (BPMs), used to monitor the position of the electron beam, require a greater stability than other mechanical structures. This paper concentrates on an investigation of the dynamic performance of the BPM support prototype. Modal and response analyses have been carried out by finite-element (FE) calculations and vibration measurements. Inconsistent results between calculation and measurement have motivated a change in the soft connections between the support and the ground from a ground bolt in the initial design to full grout. As a result the mechanical stability of the BPM support is greatly improved, showing an increase in the first eigenfrequency from 20.2 Hz to 50.2 Hz and a decrease in the ratio of the root-mean-square displacement (4-50 Hz) between the ground and the top of the support from 4.36 to 1.23 in the lateral direction. An example is given to show how FE analysis can guide the mechanical design and dynamic measurements (i.e. it is not just used as a verification method). Similar ideas can be applied to improve the stability of other mechanical structures.

Regridding reconstruction algorithm for real-time tomographic imaging

PubMed Central

Marone, F.; Stampanoni, M.

2012-01-01

Sub-second temporal-resolution tomographic microscopy is becoming a reality at third-generation synchrotron sources. Efficient data handling and post-processing is, however, difficult when the data rates are close to 10 GB s−1. This bottleneck still hinders exploitation of the full potential inherent in the ultrafast acquisition speed. In this paper the fast reconstruction algorithm gridrec, highly optimized for conventional CPU technology, is presented. It is shown that gridrec is a valuable alternative to standard filtered back-projection routines, despite being based on the Fourier transform method. In fact, the regridding procedure used for resampling the Fourier space from polar to Cartesian coordinates couples excellent performance with negligible accuracy degradation. The stronger dependence of the observed signal-to-noise ratio for gridrec reconstructions on the number of angular views makes the presented algorithm even superior to filtered back-projection when the tomographic problem is well sampled. Gridrec not only guarantees high-quality results but it provides up to 20-fold performance increase, making real-time monitoring of the sub-second acquisition process a reality. PMID:23093766

New experimental perspectives for soft x-ray absorption spectroscopies at ultra-low temperatures below 50 mK and in high magnetic fields up to 7 T

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beeck, T., E-mail: torben.beeck@desy.de; Baev, I.; Gieschen, S.

2016-04-15

A new ultra-low temperature experiment including a superconducting vector magnet has been developed for soft x-ray absorption spectroscopy experiments at third generation synchrotron light sources. The sample is cooled below 50 mK by a cryogen free {sup 3}He-{sup 4}He dilution refrigerator. At the same time, magnetic fields of up to ±7 T in the horizontal direction and ±0.5 T in the vertical direction can be applied by a superconducting vector magnet. The setup allows to study ex situ and in situ prepared samples, offered by an attached UHV preparation chamber with load lock. The transfer of the prepared samples betweenmore » the preparation section and the dilution refrigerator is carried out under cryogenic temperatures. First commissioning studies have been carried out at the Variable Polarization XUV Beamline P04 at PETRA III and the influence of the incident photon beam to the sample temperature has been studied.« less

Experimental and theoretical charge density studies at subatomic resolution.

PubMed

Fischer, A; Tiana, D; Scherer, W; Batke, K; Eickerling, G; Svendsen, H; Bindzus, N; Iversen, B B

2011-11-17

Analysis of accurate experimental and theoretical structure factors of diamond and silicon reveals that the contraction of the core shell due to covalent bond formation causes significant perturbations of the total charge density that cannot be ignored in precise charge density studies. We outline that the nature and origin of core contraction/expansion and core polarization phenomena can be analyzed by experimental studies employing an extended Hansen-Coppens multipolar model. Omission or insufficient treatment of these subatomic charge density phenomena might yield erroneous thermal displacement parameters and high residual densities in multipolar refinements. Our detailed studies therefore suggest that the refinement of contraction/expansion and population parameters of all atomic shells is essential to the precise reconstruction of electron density distributions by a multipolar model. Furthermore, our results imply that also the polarization of the inner shells needs to be adopted, especially in cases where second row or even heavier elements are involved in covalent bonding. These theoretical studies are supported by direct multipolar refinements of X-ray powder diffraction data of diamond obtained from a third-generation synchrotron-radiation source (SPring-8, BL02B2).

A fresh look at the photoelectron spectrum of bromobenzene: A third-order non-Dyson electron propagator study.

PubMed

Schneider, M; Soshnikov, D Yu; Holland, D M P; Powis, I; Antonsson, E; Patanen, M; Nicolas, C; Miron, C; Wormit, M; Dreuw, A; Trofimov, A B

2015-10-14

The valence-shell ionization spectrum of bromobenzene, as a representative halogen substituted aromatic, was studied using the non-Dyson third-order algebraic-diagrammatic construction [nD-ADC(3)] approximation for the electron propagator. This method, also referred to as IP-ADC(3), was implemented as a part of the Q-Chem program and enables large-scale calculations of the ionization spectra, where the computational effort scales as n(5) with respect to the number of molecular orbitals n. The IP-ADC(3) scheme is ideally suited for investigating low-lying ionization transitions, so fresh insight could be gained into the cationic state manifold of bromobenzene. In particular, the present IP-ADC(3) calculations with the cc-pVTZ basis reveal a whole class of low-lying low-intensity two-hole-one-particle (2h-1p) doublet and quartet states, which are relevant to various photoionization processes. The good qualitative agreement between the theoretical spectral profile for the valence-shell ionization transitions generated with the smaller cc-pVDZ basis set and the experimental photoelectron spectrum measured at a photon energy of 80 eV on the PLÉIADES beamline at the Soleil synchrotron radiation source allowed all the main features to be assigned. Some theoretical aspects of the ionization energy calculations concerning the use of various approximation schemes and basis sets are discussed.

A fresh look at the photoelectron spectrum of bromobenzene: A third-order non-Dyson electron propagator study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schneider, M.; Wormit, M.; Dreuw, A.

2015-10-14

The valence-shell ionization spectrum of bromobenzene, as a representative halogen substituted aromatic, was studied using the non-Dyson third-order algebraic-diagrammatic construction [nD-ADC(3)] approximation for the electron propagator. This method, also referred to as IP-ADC(3), was implemented as a part of the Q-Chem program and enables large-scale calculations of the ionization spectra, where the computational effort scales as n{sup 5} with respect to the number of molecular orbitals n. The IP-ADC(3) scheme is ideally suited for investigating low-lying ionization transitions, so fresh insight could be gained into the cationic state manifold of bromobenzene. In particular, the present IP-ADC(3) calculations with the cc-pVTZmore » basis reveal a whole class of low-lying low-intensity two-hole-one-particle (2h-1p) doublet and quartet states, which are relevant to various photoionization processes. The good qualitative agreement between the theoretical spectral profile for the valence-shell ionization transitions generated with the smaller cc-pVDZ basis set and the experimental photoelectron spectrum measured at a photon energy of 80 eV on the PLÉIADES beamline at the Soleil synchrotron radiation source allowed all the main features to be assigned. Some theoretical aspects of the ionization energy calculations concerning the use of various approximation schemes and basis sets are discussed.« less

SESAME, A 3rd Generation Synchrotron Light Source for the Middle East

DOE Office of Scientific and Technical Information (OSTI.GOV)

Einfeld, D.; Hasnain, S.S.; Sayers, Z.

2004-05-12

Developed under the auspices of UNESCO, SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be a major international research centre in the Middle East and Mediterranean region. On 6th of January 2003, the official foundation of SESAME took place. The facility is located in Allan, Jordan, 30 km North-West of Amman. As of August 2003 the Founding Members are Bahrain, Egypt, Iran, Israel, Jordan, Pakistan, Palestine, Turkey and United Arabic Emirates, representing a population of over 300 million. SESAME will be a 2.5 GeV 3rd Generation light source (emittance 24.6 nm.rad, circumference {approx}125m). About 40% ofmore » the circumference is available for insertion devices (average length 2.75m) in 13 straight sections. Beam lines are up to 36m. The site and a building are provided by Jordan. Construction started in August 2003. The scientific program will start with up to 6 beam lines: MAD Protein Crystallography, SAXS and WAXS for polymers and proteins, Powder Diffraction for material science, UV/VUV/SXR Photoelectron Spectroscopy and Photoabsorption Spectroscopy, IR Spectroscopy, and EXAFS.« less

Planck Early Results. XV. Spectral Energy Distributions and Radio Continuum Spectra of Northern Extragalactic Radio Sources

NASA Technical Reports Server (NTRS)

Aatrokoski, J.; Ade, P. A. R.; Aghanim, N.; Aller, H. D.; Aller, M. F.; Angelakis, E.; Amaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.;

Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources

DOE PAGES

Aatrokoski, J.

2011-12-01

Spectral energy distributions (SEDs) and radio continuum spectra are presented for a northern sample of 104 extragalactic radio sources, based on the Planck Early Release Compact Source Catalogue (ERCSC) and simultaneous multifrequency data. The nine Planck frequencies, from 30 to 857GHz, are complemented by a set of simultaneous observations ranging from radio to gamma-rays. This is the first extensive frequency coverage in the radio and millimetre domains for an essentially complete sample of extragalactic radio sources, and it shows how the individual shocks, each in their own phase of development, shape the radio spectra as they move in the relativisticmore » jet. The SEDs presented in this paper were fitted with second and third degree polynomials to estimate the frequencies of the synchrotron and inverse Compton (IC) peaks, and the spectral indices of low and high frequency radio data, including the Planck ERCSC data, were calculated. SED modelling methods are discussed, with an emphasis on proper, physical modelling of the synchrotron bump using multiple components. Planck ERCSC data also suggest that the original accelerated electron energy spectrum could be much harder than commonly thought, with power-law index around 1.5 instead of the canonical 2.5. The implications of this are discussed for the acceleration mechanisms effective in blazar shock. Furthermore in many cases the Planck data indicate that gamma-ray emission must originate in the same shocks that produce the radio emission.« less

RoboPol: the optical polarization of gamma-ray-loud and gamma-ray-quiet blazars

NASA Astrophysics Data System (ADS)

Angelakis, E.; Hovatta, T.; Blinov, D.; Pavlidou, V.; Kiehlmann, S.; Myserlis, I.; Böttcher, M.; Mao, P.; Panopoulou, G. V.; Liodakis, I.; King, O. G.; Baloković, M.; Kus, A.; Kylafis, N.; Mahabal, A.; Marecki, A.; Paleologou, E.; Papadakis, I.; Papamastorakis, I.; Pazderski, E.; Pearson, T. J.; Prabhudesai, S.; Ramaprakash, A. N.; Readhead, A. C. S.; Reig, P.; Tassis, K.; Urry, M.; Zensus, J. A.

2016-12-01

We present average R-band optopolarimetric data, as well as variability parameters, from the first and second RoboPol observing season. We investigate whether gamma-ray-loud and gamma-ray-quiet blazars exhibit systematic differences in their optical polarization properties. We find that gamma-ray-loud blazars have a systematically higher polarization fraction (0.092) than gamma-ray-quiet blazars (0.031), with the hypothesis of the two samples being drawn from the same distribution of polarization fractions being rejected at the 3σ level. We have not found any evidence that this discrepancy is related to differences in the redshift distribution, rest-frame R-band luminosity density, or the source classification. The median polarization fraction versus synchrotron-peak-frequency plot shows an envelope implying that high-synchrotron-peaked sources have a smaller range of median polarization fractions concentrated around lower values. Our gamma-ray-quiet sources show similar median polarization fractions although they are all low-synchrotron-peaked. We also find that the randomness of the polarization angle depends on the synchrotron peak frequency. For high-synchrotron-peaked sources, it tends to concentrate around preferred directions while for low-synchrotron-peaked sources, it is more variable and less likely to have a preferred direction. We propose a scenario which mediates efficient particle acceleration in shocks and increases the helical B-field component immediately downstream of the shock.

National Synchrotron Light Source

ScienceCinema

None

2017-12-09

A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

The JLab high power ERL light source

NASA Astrophysics Data System (ADS)

Neil, G. R.; Behre, C.; Benson, S. V.; Bevins, M.; Biallas, G.; Boyce, J.; Coleman, J.; Dillon-Townes, L. A.; Douglas, D.; Dylla, H. F.; Evans, R.; Grippo, A.; Gruber, D.; Gubeli, J.; Hardy, D.; Hernandez-Garcia, C.; Jordan, K.; Kelley, M. J.; Merminga, L.; Mammosser, J.; Moore, W.; Nishimori, N.; Pozdeyev, E.; Preble, J.; Rimmer, R.; Shinn, M.; Siggins, T.; Tennant, C.; Walker, R.; Williams, G. P.; Zhang, S.

2006-02-01

A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz ˜ half cycle pulse whose average brightness is >5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted [Carr, et al., Nature 420 (2002) 153]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [Neil, et al., Phys. Rev. Lett. 84 (2000) 662]: up to 10 kW of average power in the IR from 1 to 14 μm in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 ms long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made concerning the physics performance, design optimization, and operational limitations of such a first generation high power ERL light source.

Mini-beam collimator enables microcrystallography experiments on standard beamlines

PubMed Central

Fischetti, Robert F.; Xu, Shenglan; Yoder, Derek W.; Becker, Michael; Nagarajan, Venugopalan; Sanishvili, Ruslan; Hilgart, Mark C.; Stepanov, Sergey; Makarov, Oleg; Smith, Janet L.

2009-01-01

The high-brilliance X-ray beams from undulator sources at third-generation synchrotron facilities are excellent tools for solving crystal structures of important and challenging biological macromolecules and complexes. However, many of the most important structural targets yield crystals that are too small or too inhomogeneous for a ‘standard’ beam from an undulator source, ∼25–50 µm (FWHM) in the vertical and 50–100 µm in the horizontal direction. Although many synchrotron facilities have microfocus beamlines for other applications, this capability for macromolecular crystallography was pioneered at ID-13 of the ESRF. The National Institute of General Medical Sciences and National Cancer Institute Collaborative Access Team (GM/CA-CAT) dual canted undulator beamlines at the APS deliver high-intensity focused beams with a minimum focal size of 20 µm × 65 µm at the sample position. To meet growing user demand for beams to study samples of 10 µm or less, a ‘mini-beam’ apparatus was developed that conditions the focused beam to either 5 µm or 10 µm (FWHM) diameter with high intensity. The mini-beam has a symmetric Gaussian shape in both the horizontal and vertical directions, and reduces the vertical divergence of the focused beam by 25%. Significant reduction in background was achieved by implementation of both forward- and back-scatter guards. A unique triple-collimator apparatus, which has been in routine use on both undulator beamlines since February 2008, allows users to rapidly interchange the focused beam and conditioned mini-beams of two sizes with a single mouse click. The device and the beam are stable over many hours of routine operation. The rapid-exchange capability has greatly facilitated sample screening and resulted in several structures that could not have been obtained with the larger focused beam. PMID:19240333

Millimeter wave coherent synchrotron radiation in a compact electron storage ring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murphy, J.B.; Blum, E.; Heese, R.

1998-01-01

Installation of a 2,856 MHz RF system into the XLS compact electron storage ring would allow the generation of millimeter wave coherent synchrotron radiation. Operating at 150 MeV, one could produce bunches containing on the order of 2 {times} 10{sup 7} electrons with a bunch length {sigma}{sub L0} = 0.3 mm, resulting in coherent emission at wavelengths above 0.8 mm. The characteristics of the source and the emitted radiation are discussed. In the case of 100 mrad horizontal collection angle, the average power radiated in the wavelength band 1 mm {le} {lambda} {le} 2 mm is 0.3 mW for singlemore » bunch operation and 24 mW for 80 bunch operation. The peak power in a single pulse of a few picosecond duration is on the order of one watt. By reducing the momentum compaction, the bunch length could be reduced to {sigma}{sub L0} = 0.15 mm, resulting in coherent synchrotron radiation down to 500 {micro}m.« less

System and method for investigating sub-surface features of a rock formation using compressional acoustic sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vu, Cung Khac; Skelt, Christopher; Nihei, Kurt

A system and method for investigating rock formations outside a borehole are provided. The method includes generating a first compressional acoustic wave at a first frequency by a first acoustic source; and generating a second compressional acoustic wave at a second frequency by a second acoustic source. The first and the second acoustic sources are arranged within a localized area of the borehole. The first and the second acoustic waves intersect in an intersection volume outside the borehole. The method further includes receiving a third shear acoustic wave at a third frequency, the third shear acoustic wave returning to themore » borehole due to a non-linear mixing process in a non-linear mixing zone within the intersection volume at a receiver arranged in the borehole. The third frequency is equal to a difference between the first frequency and the second frequency.« less

Micron Scale Mineralogy

NASA Astrophysics Data System (ADS)

Caldwell, W. A.; Tamura, N.; Celestre, R. S.; Padmore, H. A.; Patel, J. R.

2002-12-01

Although x-ray diffraction has been used for nearly a century as the mineralogist's definitive tool in determining crystalline structures, it has proved impossible to use this technique to spatially resolve the highly heterogeneous nature of many minerals at the mesoscopic level. Due to recent revolutions in the brightness of x-ray sources and in our ability to focus x-rays, we can now carry out conventional monochromatic rotation crystallography as well as Laue diffraction with sub-micron spatial resolution and produce maps of orientation, strain, mineral type, and even chemical speciation over tens of microns in a short amount of time. We have pioneered the development of these techniques at the 3rd generation synchrotron radiation source (Advanced Light Source) in Berkeley, and will describe their application to understanding the structure of a quartz-geode. Our results show the manner in which grain structure and texture change as a function of distance from the cavity wall and are compared with models of crystal growth in such systems. This example highlights the great utility of a synchrotron based x-ray micro-diffraction beamline and the possibilities it opens to the mineralogist.

Initial results of a new generation dual source CT system using only an in-plane comb filter for ultra-high resolution temporal bone imaging.

PubMed

Meyer, Mathias; Haubenreisser, Holger; Raupach, Rainer; Schmidt, Bernhard; Lietzmann, Florian; Leidecker, Christianne; Allmendinger, Thomas; Flohr, Thomas; Schad, Lothar R; Schoenberg, Stefan O; Henzler, Thomas

2015-01-01

To prospectively evaluate radiation dose and image quality of a third generation dual-source CT (DSCT) without z-axis filter behind the patient for temporal bone CT. Forty-five patients were either examined on a first, second, or third generation DSCT in an ultra-high-resolution (UHR) temporal bone-imaging mode. On the third generation DSCT system, the tighter focal spot of 0.2 mm(2) removes the necessity for an additional z-axis-filter, leading to an improved z-axis radiation dose efficiency. Images of 0.4 mm were reconstructed using standard filtered-back-projection or iterative reconstruction (IR) technique for previous generations of DSCT and a novel IR algorithm for the third generation DSCT. Radiation dose and image quality were compared between the three DSCT systems. The statistically significantly highest subjective and objective image quality was evaluated for the third generation DSCT when compared to the first or second generation DSCT systems (all p < 0.05). Total effective dose was 63%/39% lower for the third generation examination as compared to the first and second generation DSCT. Temporal bone imaging without z-axis-UHR-filter and a novel third generation IR algorithm allows for significantly higher image quality while lowering effective dose when compared to the first two generations of DSCTs. • Omitting the z-axis-filter allows a reduction in radiation dose of 50% • A smaller focal spot of 0.2 mm (2) significantly improves spatial resolution • Ultra-high-resolution temporal-bone-CT helps to gain diagnostic information of the middle/inner ear.

Examining Returned Samples in their Collection Tubes Using Synchrotron Radiation-Based Techniques

NASA Astrophysics Data System (ADS)

Schoonen, M. A.; Hurowitz, J. A.; Thieme, J.; Dooryhee, E.; Fogelqvist, E.; Gregerson, J.; Farley, K. A.; Sherman, S.; Hill, J.

2018-04-01

Synchrotron radiation-based techniques can be leveraged for triaging and analysis of returned samples before unsealing collection tubes. Proof-of-concept measurements conducted at Brookhaven National Lab's National Synchrotron Light Source-II.

National Synchrotron Light Source II

ScienceCinema

Steve Dierker

2017-12-09

The National Synchrotron Light Source II (NSLS-II) at the U.S. Department of Energy's Brookhaven National Laboratory is a proposed new state-of-the-art medium energy storage ring designed to deliver world-leading brightness and flux with top-off operation

Studies of atomic and molecular dynamics using photoelectron spectroscopy

NASA Astrophysics Data System (ADS)

Canton, Sophie E.

Photoexcitation and photoionization studies of free atoms and molecules in the gas phase provide a unique view into various aspects of radiation-matter interactions that are used as basic building blocks in many branches of physics, such as Solid State, Plasma Physics, Photochemistry or Astrophysics. With the advent of third generation synchrotron light sources delivering high photon flux (>1015 photons/s) with unprecedented resolving power over a broad energy range, it has become possible to investigate in great detail not only the internal structure of the targets, but also the dynamics of the process. Born in the 1960s, photoelectron spectroscopy specifically analyzes the kinetic energy and emission angle of the ionized electrons. It is now coming to maturity with the availability of spectrometers designed to achieve high performances. This thesis work presents three examples of experiments made possible by the combination of the radiation from the Advanced Light Source with state of the art spectrometers. First, the measurements of the partial photoionization cross sections below the second ionization potential in argon and neon have uncovered weak and narrow resonances. Their mirroring profiles in the two open channels, which had prevented them from being detected in non-differential measurements, have been explained by their LS-forbidden nature. Second, the Auger spectra produced by decay of core-excited HF have revealed specific nuclear wavepacket interferences that occur when the electronic lifetime, the nuclear dynamics and the excitation prolongation, defined as the inverse of the photon bandwidth, have comparable time scales. Third, the analysis of the underlying structure in the first ionization band for free C60 has allowed the vibronic coupling of the singly charged molecular ion to be characterized.

Magnetic measurements of the injector synchrotron magnets for the advanced photon source

NASA Astrophysics Data System (ADS)

Kim, S. H.; Carnegie, D. W.; Doose, C. L.; Hogrefe, R.; Kim, K.; Merl, R.; Turner, L. R.

1994-07-01

The magnetic measurement data of the dipole, quadrupole, and sextupole magnets for the Advanced Photon Source injector synchrotron are summarized. Magnet design and magnetic measurements of the field strength, field shape, and multipole coefficients are described.

Diffraction and Transmission Synchrotron Imaging at the German Light Source ANKA--Potential Industrial Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rack, Alexander; Weitkamp, Timm; European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex

2009-03-10

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

X-ray photonic microsystems for the manipulation of synchrotron light

DOE PAGES

Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; ...

2015-05-05

In this study, photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractivemore » optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.« less

Theory of electromagnetic insertion devices and the corresponding synchrotron radiation

NASA Astrophysics Data System (ADS)

Shumail, Muhammad; Tantawi, Sami G.

2016-07-01

Permanent magnet insertion devices (IDs), which are the main radiation generating devices in synchrotron light sources and free-electron lasers, use a time-invariant but space-periodic magnetic field to wiggle relativistic electrons for short-wavelength radiation generation. Recently, a high power microwave based undulator has also been successfully demonstrated at SLAC which promises the advantage of dynamic tunability of radiation spectrum and polarization. Such IDs employ transverse elecromagnetic fields which are periodic in both space and time to undulate the electrons. In this paper we develop a detailed theory of the principle of electromagnetic IDs from first principles for both linear and circular polarization modes. The electromagnetic equivalent definitions of undulator period (λu) and undulator deflection parameter (K ) are derived. In the inertial frame where the average momentum of the electron is zero, we obtain the figure-8-like trajectory for the linear polarization mode and the circular trajectory for the circular polarization mode. The corresponding radiation spectra and the intensity of harmonics is also calculated.

Shielding calculations for the National Synchrotron Light Source-II experimental beamlines

NASA Astrophysics Data System (ADS)

Job, Panakkal K.; Casey, William R.

2013-01-01

Brookhaven National Laboratory is in the process of building a new Electron storage ring for scientific research using synchrotron radiation. This facility, called the "National Synchrotron Light Source II" (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors, and robotics, designed to maximize the scientific output of the facility. The project scope includes the design of an electron storage ring and the experimental beamlines, which stores a maximum of 500 mA electron beam current at an energy of 3.0 GeV. When fully built there will be at least 58 beamlines using synchrotron radiation for experimental programs. It is planned to operate the facility primarily in a top-off mode, thereby maintaining the maximum variation in the synchrotron radiation flux to <1%. Because of the very demanding requirements for synchrotron radiation brilliance for the experiments, each of the 58 beamlines will be unique in terms of the source properties and experimental configuration. This makes the shielding configuration of each of the beamlines unique. The shielding calculation methodology and the results for five representative beamlines of NSLS-II, have been presented in this paper.

Fluorescence tomography using synchrotron radiation at the NSLS

NASA Astrophysics Data System (ADS)

Boisseau, P.; Grodzins, L.

1987-03-01

Fluorescence tomography utilizing focussed, tunable, monoenergetic X-rays from synchrotron light sources hold the promise of a non-invasive analytic tool for studying trace elements in specimens, particularly biological, at spatial resolutions of the order of micrometers. This note reports an early test at the National Synchrotron Light Source at Brookhaven National Laboratories in which fluorescence tomographic scans were successfully made of trace elements of iron and titanium in NBS standard glass and in a bee.

Power Supplies for High Energy Particle Accelerators

NASA Astrophysics Data System (ADS)

Dey, Pranab Kumar

2016-06-01

The on-going research and the development projects with Large Hadron Collider at CERN, Geneva, Switzerland has generated enormous enthusiasm and interest amongst all to know about the ultimate findings on `God's Particle'. This paper has made an attempt to unfold the power supply requirements and the methodology adopted to provide the stringent demand of such high energy particle accelerators during the initial stages of the search for the ultimate particles. An attempt has also been made to highlight the present status on the requirement of power supplies in some high energy accelerators with a view that, precautionary measures can be drawn during design and development from earlier experience which will be of help for the proposed third generation synchrotron to be installed in India at a huge cost.

Synchrotron Radiation from Ultra-High Energy Protons and the Fermi Observations of GRB 080916C

DTIC Science & Technology

2010-01-01

compared with keV – MeV radiation. Here we show that synchrotron radiation from cosmic ray protons accelerated in GRBs, delayed by the proton synchrotron... cosmic rays from sources within 100 Mpc for nano-Gauss intergalactic magnetic fields. The total energy requirements in a proton synchrotron model are...component arising from cosmic - ray proton synchrotron radiation explains the delayed onset of the LAT emission. If GRBs accelerate UHECRs, then the

Author Contribution to the Pu Handbook II: Chapter 37 LLNL Integrated Sample Preparation Glovebox (TEM) Section

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wall, Mark A.

The development of our Integrated Actinide Sample Preparation Laboratory (IASPL) commenced in 1998 driven by the need to perform transmission electron microscopy studies on naturally aged plutonium and its alloys looking for the microstructural effects of the radiological decay process (1). Remodeling and construction of a laboratory within the Chemistry and Materials Science Directorate facilities at LLNL was required to turn a standard radiological laboratory into a Radiological Materials Area (RMA) and Radiological Buffer Area (RBA) containing type I, II and III workplaces. Two inert atmosphere dry-train glove boxes with antechambers and entry/exit fumehoods (Figure 1), having a baseline atmospheremore » of 1 ppm oxygen and 1 ppm water vapor, a utility fumehood and a portable, and a third double-walled enclosure have been installed and commissioned. These capabilities, along with highly trained technical staff, facilitate the safe operation of sample preparation processes and instrumentation, and sample handling while minimizing oxidation or corrosion of the plutonium. In addition, we are currently developing the capability to safely transfer small metallographically prepared samples to a mini-SEM for microstructural imaging and chemical analysis. The gloveboxes continue to be the most crucial element of the laboratory allowing nearly oxide-free sample preparation for a wide variety of LLNL-based characterization experiments, which includes transmission electron microscopy, electron energy loss spectroscopy, optical microscopy, electrical resistivity, ion implantation, X-ray diffraction and absorption, magnetometry, metrological surface measurements, high-pressure diamond anvil cell equation-of-state, phonon dispersion measurements, X-ray absorption and emission spectroscopy, and differential scanning calorimetry. The sample preparation and materials processing capabilities in the IASPL have also facilitated experimentation at world-class facilities such as the Advanced Photon Source at Argonne National Laboratory, the European Synchrotron Radiation Facility in Grenoble, France, the Stanford Synchrotron Radiation Facility, the National Synchrotron Light Source at Brookhaven National Laboratory, the Advanced Light Source at Lawrence Berkeley National Laboratory, and the Triumph Accelerator in Canada.« less

Chemical applications of synchrotron radiation: Workshop report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-04-01

The most recent in a series of topical meetings for Advanced Photon Source user subgroups, the Workshop on Chemical Applications of Synchrotron Radiation (held at Argonne National Laboratory, October 3-4, 1988) dealt with surfaces and kinetics, spectroscopy, small-angle scattering, diffraction, and topography and imaging. The primary objectives were to provide an educational resource for the chemistry community on the scientific research being conducted at existing synchrotron sources and to indicate some of the unique opportunities that will be made available with the Advanced Photon Source. The workshop organizers were also interested in gauging the interest of chemists in the fieldmore » of synchrotron radiation. Interest expressed at the meeting has led to initial steps toward formation of a Chemistry Users Group at the APS. Individual projects are processed separately for the data bases.« less

Photon Science for Renewable Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hussain, Zahid; Tamura, Lori; Padmore, Howard

2010-03-31

Our current fossil-fuel-based system is causing potentially catastrophic changes to our planet. The quest for renewable, nonpolluting sources of energy requires us to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels. Light-source facilities - the synchrotrons of today and the next-generation light sources of tomorrow - are the scientific tools of choice for exploring the electronic and atomic structure of matter. As such, these photon-science facilities are uniquely positioned to jump-start a global revolution in renewable and carbonneutral energy technologies. In these pages, we outline and illustrate through examples from our nation's lightmore » sources possible scientific directions for addressing these profound yet urgent challenges.« less

EXTRAGALACTIC MILLIMETER-WAVE SOURCES IN SOUTH POLE TELESCOPE SURVEY DATA: SOURCE COUNTS, CATALOG, AND STATISTICS FOR AN 87 SQUARE-DEGREE FIELD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vieira, J. D.; Crawford, T. M.; Switzer, E. R.

2010-08-10

We report the results of an 87 deg{sup 2} point-source survey centered at R.A. 5{sup h}30{sup m}, decl. -55{sup 0} taken with the South Pole Telescope at 1.4 and 2.0 mm wavelengths with arcminute resolution and milli-Jansky depth. Based on the ratio of flux in the two bands, we separate the detected sources into two populations, one consistent with synchrotron emission from active galactic nuclei and the other consistent with thermal emission from dust. We present source counts for each population from 11 to 640 mJy at 1.4 mm and from 4.4 to 800 mJy at 2.0 mm. The 2.0more » mm counts are dominated by synchrotron-dominated sources across our reported flux range; the 1.4 mm counts are dominated by synchrotron-dominated sources above {approx}15 mJy and by dust-dominated sources below that flux level. We detect 141 synchrotron-dominated sources and 47 dust-dominated sources at signal-to-noise ratio S/N >4.5 in at least one band. All of the most significantly detected members of the synchrotron-dominated population are associated with sources in previously published radio catalogs. Some of the dust-dominated sources are associated with nearby (z << 1) galaxies whose dust emission is also detected by the Infrared Astronomy Satellite. However, most of the bright, dust-dominated sources have no counterparts in any existing catalogs. We argue that these sources represent the rarest and brightest members of the population commonly referred to as submillimeter galaxies (SMGs). Because these sources are selected at longer wavelengths than in typical SMG surveys, they are expected to have a higher mean redshift distribution and may provide a new window on galaxy formation in the early universe.« less

Ion Sources

NASA Astrophysics Data System (ADS)

Haseroth, Helmut; Hora, Heinrich

1993-03-01

Ion sources for accelerators are based on plasma configurations with an extraction system in order to gain a very high number of ions within an appropriately short pulse and of sufficiently high charge number Z for advanced research. Beginning with the duoplasmatron, all established ion sources are based on low-density plasmas, of which the electron beam ionization source (EBIS) and the electron cyclotron resonance (ECR) source are the most advanced; for example they result in pulses of nearly 6 × 108 fully stripped sulfur ions per pulse in the Super Proton Synchrotron (SPS) at CERN with energies of 200 GeV/u. As an example of a forthcoming development, we are reporting about the lead ion source for the same purpose. Contrary to these cases of low-density plasmas, where a rather long time is always necessary to generate sufficiently high charge states, the laser ion source uses very high density plasmas and therefore produced, for example in 1983, single shots of Au51+ ions of high directivity with energies above 300 MeV within 2 ns irradiation time of a gold target with a medium-to-large CO2 laser. Experiments at Dubna and Moscow, using small-size lasers, produced up to one million shots with 1 Hz sequence. After acceleration by a linac or otherwise, ion pulses of up to nearly 5 × 1010 ions of C4+ or Mg12+ with energies in the synchrotrons of up to 2 GeV/u were produced. The physics of the laser generation of the ions is most complex, as we know from laser fusion studies, including non-linear dynamic and dielectric effects, resonances, self-focusing, instabilities, double layers, and an irregular pulsation in the 20 ps range. This explains not only what difficulties are implied with the laser ion source, but also why it opens up a new direction of ion sources.

Studies of longitudinal profile of electron bunches and impedance measurements at Indus-2 synchrotron radiation source

NASA Astrophysics Data System (ADS)

Garg, Akash Deep; Yadav, S.; Kumar, Mukesh; Shrivastava, B. B.; Karnewar, A. K.; Ojha, A.; Puntambekar, T. A.

2016-04-01

Indus-2 is a 3rd generation synchrotron radiation source at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We study the longitudinal profile of electrons in Indus-2 by using dual sweep synchroscan streak camera at visible diagnostic beamline. In this paper, the longitudinal profiles of electron bunch are analyzed by filling beam current in a single bunch mode. These studies are carried at injection energy (550 MeV) and at ramped beam energy (2.5 GeV). The effects of the wakefield generated interactions between the circulating electrons and the surrounding vacuum chamber are analyzed in terms of measured effects on longitudinal beam distribution. The impedance of the storage ring is obtained by fitting the solutions of Haissinski equation to the measured bunch lengthening with different impedance models. The impedance of storage ring obtained by a series R+L impedance model indicates a resistance (R) of 1350±125 Ω, an inductance (L) of 180±25 nH and broadband impedance of 2.69 Ω. These results are also compared with the values obtained from measured synchronous phase advancing and scaling laws. These studies are very useful in better understanding and control of the electromagnetic interactions.

Variable magnification with Kirkpatrick-Baez optics for synchrotron X-ray microscopy

DOE PAGES

Jach, Terrence; Bakulin, Alex S.; Durbin, Stephen M.; ...

2006-05-01

In this study, we describe the distinction between the operation of a short focal length x-ray microscope forming a real image with a laboratory source (convergent illumination) and with a highly collimated intense beam from a synchrotron light source (Kohler illumination).

SYNCHROTRON RADIATION, FREE ELECTRON LASER, APPLICATION OF NUCLEAR TECHNOLOGY, ETC.: Study on the characteristics of linac based THz light source

NASA Astrophysics Data System (ADS)

Zhu, Xiong-Wei; Wang, Shu-Hong; Chen, Sen-Yu

2009-10-01

There are many methods based on linac for THz radiation production. As one of the options for the Beijing Advanced Light, an ERL test facility is proposed for THz radiation. In this test facility, there are 4 kinds of methods to produce THz radiation: coherent synchrotron radiation (CSR), synchrotron radiation (SR), low gain FEL oscillator, and high gain SASE FEL. In this paper, we study the characteristics of the 4 kinds of THz light sources.

Single-crystal diamond refractive lens for focusing X-rays in two dimensions.

PubMed

Antipov, S; Baryshev, S V; Butler, J E; Antipova, O; Liu, Z; Stoupin, S

2016-01-01

The fabrication and performance evaluation of single-crystal diamond refractive X-ray lenses of which the surfaces are paraboloids of revolution for focusing X-rays in two dimensions simultaneously are reported. The lenses were manufactured using a femtosecond laser micromachining process and tested using X-ray synchrotron radiation. Such lenses were stacked together to form a standard compound refractive lens (CRL). Owing to the superior physical properties of the material, diamond CRLs could become indispensable wavefront-preserving primary focusing optics for X-ray free-electron lasers and the next-generation synchrotron storage rings. They can be used for highly efficient refocusing of the extremely bright X-ray sources for secondary optical schemes with limited aperture such as nanofocusing Fresnel zone plates and multilayer Laue lenses.

Single-crystal diamond refractive lens for focusing X-rays in two dimensions

PubMed Central

Antipov, S.; Baryshev, S. V.; Butler, J. E.; Antipova, O.; Liu, Z.; Stoupin, S.

2016-01-01

The fabrication and performance evaluation of single-crystal diamond refractive X-ray lenses of which the surfaces are paraboloids of revolution for focusing X-rays in two dimensions simultaneously are reported. The lenses were manufactured using a femtosecond laser micromachining process and tested using X-ray synchrotron radiation. Such lenses were stacked together to form a standard compound refractive lens (CRL). Owing to the superior physical properties of the material, diamond CRLs could become indispensable wavefront-preserving primary focusing optics for X-ray free-electron lasers and the next-generation synchrotron storage rings. They can be used for highly efficient refocusing of the extremely bright X-ray sources for secondary optical schemes with limited aperture such as nanofocusing Fresnel zone plates and multilayer Laue lenses. PMID:26698059

Single-crystal diamond refractive lens for focusing X-rays in two dimensions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Antipov, S.; Baryshev, Sergey; Butler, J. E.

2016-01-01

The fabrication and performance evaluation of single-crystal diamond refractive X-ray lenses of which the surfaces are paraboloids of revolution for focusing X-rays in two dimensions simultaneously are reported. The lenses were manufactured using a femtosecond laser micromachining process and tested using X-ray synchrotron radiation. Such lenses were stacked together to form a standard compound refractive lens (CRL). Owing to the superior physical properties of the material, diamond CRLs could become indispensable wavefront-preserving primary focusing optics for X-ray free-electron lasers and the next-generation synchrotron storage rings. They can be used for highly efficient refocusing of the extremely bright X-ray sources formore » secondary optical schemes with limited aperture such as nanofocusing Fresnel zone plates and multilayer Laue lenses.« less

The Scale Invariant Synchrotron Jet of Flat Spectrum Radio Quasars

NASA Astrophysics Data System (ADS)

Du, L. M.; Bai, J. M.; Xie, Z. H.; Yi, T. F.; Xu, Y. B.; Xue, R.; Wang, X. H.

2015-06-01

In this paper, the scale invariance of the synchrotron jet of Flat Spectrum Radio Quasars has been studied using a sample of combined sources from FKM04 and from SDSS DR3 catalogue. Since the research of scale invariance has been focused on sub-Eddington cases that can be fitted onto the fundamental plane, while near-Eddington sources such as FSRQs have not been explicitly studied. The extracted physical properties of synchrotron jet of FSRQs have been shown to be scale invariant using our sample. The results are in good agreement with theoretical expectations of Heinz & Sunyaev (2003). Therefore, the jet synchrotron is shown to be scale independent, regardless of the accretion modes. Results in this article thus lend support to the scale invariant model of the jet synchrotron throughout the mass scale of black hole systems.

The crystalline sponge method: MOF terminal ligand effects† †Electronic supplementary information (ESI) available: Experimental and crystallographic procedures, and data tables. CCDC 1063685 and 1063686. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5cc03840e Click here for additional data file. Click here for additional data file.

PubMed Central

Ramadhar, Timothy R.; Zheng, Shao-Liang; Chen, Yu-Sheng

2015-01-01

Bromide and chloride analogs of the commonly used zinc iodide-based metal organic framework for the crystalline sponge method were synthesized and evaluated. Inclusion of (1R)-(–)-menthyl acetate into these MOFs was analysed using third-generation synchrotron radiation, and the effects and potential benefits of varying the MOF terminal ligand are discussed. PMID:26081991

6th International Conference on Biophysics & Synchrotron Radiation. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moffat, Keith

1999-08-03

The 6th International Conference on Biophysics and Synchrotron Rdiation was held at the Advanced Photon Source, Argonne National Laboratory, from August 4-8, 1998, with pre-conference activities on August 3. Over 300 attendees and 65 presenters participated in the conference that was collaboratively hosted by the University of Chicago, Center for Advanced Radiation Sources and the Advanced Photon Source.

National Synchrotron Light Source

ScienceCinema

BNL

2017-12-09

A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

Time-resolved structural studies at synchrotrons and X-ray free electron lasers: opportunities and challenges

PubMed Central

Neutze, Richard; Moffat, Keith

2012-01-01

X-ray free electron lasers (XFELs) are potentially revolutionary X-ray sources because of their very short pulse duration, extreme peak brilliance and high spatial coherence, features that distinguish them from today’s synchrotron sources. We review recent time-resolved Laue diffraction and time-resolved wide angle X-ray scattering (WAXS) studies at synchrotron sources, and initial static studies at XFELs. XFELs have the potential to transform the field of time-resolved structural biology, yet many challenges arise in devising and adapting hardware, experimental design and data analysis strategies to exploit their unusual properties. Despite these challenges, we are confident that XFEL sources are poised to shed new light on ultrafast protein reaction dynamics. PMID:23021004

Non-Destructive Trace Element Tomography Using Europe's Brightest Synchrotron Sources (ESRF-Grenoble, DESY-Hamburg) — Towards a Better Understanding of Martian Samples

NASA Astrophysics Data System (ADS)

Brenker, F. E.; Vincze, L.; Vekemans, B.; de Poulle, E.

2018-04-01

Synchrotron sources are valuable tools to measure the main and trace element content of extraterrestrial samples. The non-destructive measurements will allow to identify important geological processes within the martian mantle and crust.

Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources.

PubMed

Rutherford, Michael E; Chapman, David J; White, Thomas G; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E

2016-05-01

The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits).

Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources

PubMed Central

Rutherford, Michael E.; Chapman, David J.; White, Thomas G.; Drakopoulos, Michael; Rack, Alexander; Eakins, Daniel E.

2016-01-01

The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments. The response of a scintillator to periodic synchrotron X-ray excitation is modelled and validated against experimental data collected at the Diamond Light Source (DLS) and European Synchrotron Radiation Facility (ESRF). An upper bound on the dynamic range accessible in a time-resolved experiment for a given bunch separation is calculated for a range of scintillators. New bunch structures are suggested for DLS and ESRF using the highest-performing commercially available crystal LYSO:Ce, allowing time-resolved experiments with an interframe time of 189 ns and a maximum dynamic range of 98 (6.6 bits). PMID:27140147

Broadband Spectral Modeling of the Extreme Gigahertz-peaked Spectrum Radio Source PKS B0008-421

NASA Astrophysics Data System (ADS)

Callingham, J. R.; Gaensler, B. M.; Ekers, R. D.; Tingay, S. J.; Wayth, R. B.; Morgan, J.; Bernardi, G.; Bell, M. E.; Bhat, R.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Deshpande, A. A.; Ewall-Wice, A.; Feng, L.; Greenhill, L. J.; Hazelton, B. J.; Hindson, L.; Hurley-Walker, N.; Jacobs, D. C.; Johnston-Hollitt, M.; Kaplan, D. L.; Kudrayvtseva, N.; Lenc, E.; Lonsdale, C. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Offringa, A. R.; Ord, S. M.; Pindor, B.; Prabu, T.; Procopio, P.; Riding, J.; Srivani, K. S.; Subrahmanyan, R.; Udaya Shankar, N.; Webster, R. L.; Williams, A.; Williams, C. L.

2015-08-01

We present broadband observations and spectral modeling of PKS B0008-421 and identify it as an extreme gigahertz-peaked spectrum (GPS) source. PKS B0008-421 is characterized by the steepest known spectral slope below the turnover, close to the theoretical limit of synchrotron self-absorption, and the smallest known spectral width of any GPS source. Spectral coverage of the source spans from 0.118 to 22 GHz, which includes data from the Murchison Widefield Array and the wide bandpass receivers on the Australia Telescope Compact Array. We have implemented a Bayesian inference model fitting routine to fit the data with internal free-free absorption (FFA), single- and double-component FFA in an external homogeneous medium, FFA in an external inhomogeneous medium, or single- and double-component synchrotron self-absorption models, all with and without a high-frequency exponential break. We find that without the inclusion of a high-frequency break these models cannot accurately fit the data, with significant deviations above and below the peak in the radio spectrum. The addition of a high-frequency break provides acceptable spectral fits for the inhomogeneous FFA and double-component synchrotron self-absorption models, with the inhomogeneous FFA model statistically favored. The requirement of a high-frequency spectral break implies that the source has ceased injecting fresh particles. Additional support for the inhomogeneous FFA model as being responsible for the turnover in the spectrum is given by the consistency between the physical parameters derived from the model fit and the implications of the exponential spectral break, such as the necessity of the source being surrounded by a dense ambient medium to maintain the peak frequency near the gigahertz region. This implies that PKS B0008-421 should display an internal H i column density greater than 1020 cm-2. The discovery of PKS B0008-421 suggests that the next generation of low radio frequency surveys could reveal a large population of GPS sources that have ceased activity, and that a portion of the ultra-steep-spectrum source population could be composed of these GPS sources in a relic phase.

Line focus x-ray tubes—a new concept to produce high brilliance x-rays

NASA Astrophysics Data System (ADS)

Bartzsch, Stefan; Oelfke, Uwe

2017-11-01

Currently hard coherent x-ray radiation at high photon fluxes can only be produced with large and expensive radiation sources, such as 3rd generation synchrotrons. Especially in medicine, this limitation prevents various promising developments in imaging and therapy from being translated into clinical practice. Here we present a new concept of highly brilliant x-ray sources, line focus x-ray tubes (LFXTs), which may serve as a powerful and cheap alternative to synchrotrons and a range of other existing technologies. LFXTs employ an extremely thin focal spot and a rapidly rotating target for the electron beam which causes a change in the physical mechanism of target heating, allowing higher electron beam intensities at the focal spot. Monte Carlo simulations and numeric solutions of the heat equation are used to predict the characteristics of the LFXT. In terms of photon flux and coherence length, the performance of the line focus x-ray tube compares with inverse Compton scattering sources. Dose rates of up to 180 Gy s-1 can be reached in 50 cm distance from the focal spot. The results demonstrate that the line focus tube can serve as a powerful compact source for phase contrast imaging and microbeam radiation therapy. The production of a prototype seems technically feasible.

Microbeam radiation therapy

NASA Astrophysics Data System (ADS)

Laissue, Jean A.; Lyubimova, Nadia; Wagner, Hans-Peter; Archer, David W.; Slatkin, Daniel N.; Di Michiel, Marco; Nemoz, Christian; Renier, Michel; Brauer, Elke; Spanne, Per O.; Gebbers, Jan-Olef; Dixon, Keith; Blattmann, Hans

1999-10-01

The central nervous system of vertebrates, even when immature, displays extraordinary resistance to damage by microscopically narrow, multiple, parallel, planar beams of x rays. Imminently lethal gliosarcomas in the brains of mature rats can be inhibited and ablated by such microbeams with little or no harm to mature brain tissues and neurological function. Potentially palliative, conventional wide-beam radiotherapy of malignant brain tumors in human infants under three years of age is so fraught with the danger of disrupting the functional maturation of immature brain tissues around the targeted tumor that it is implemented infrequently. Other kinds of therapy for such tumors are often inadequate. We suggest that microbeam radiation therapy (MRT) might help to alleviate the situation. Wiggler-generated synchrotron x-rays were first used for experimental microplanar beam (microbeam) radiation therapy (MRT) at Brookhaven National Laboratory's National Synchrotron Light Source in the early 1990s. We now describe the progress achieved in MRT research to date using immature and adult rats irradiated at the European Synchrotron Radiation Facility in Grenoble, France, and investigated thereafter at the Institute of Pathology of the University of Bern.

Rapid time-resolved diffraction studies of protein structures using synchrotron radiation

NASA Astrophysics Data System (ADS)

Bartunik, Hans D.; Bartunik, Lesley J.

1992-07-01

The crystal structure of intermediate states in biological reactions of proteins of multi-protein complexes may be studied by time-resolved X-ray diffraction techniques which make use of the high spectral brilliance, continuous wavelength distribution and pulsed time structure of synchrotron radiation. Laue diffraction methods provide a means of investigating intermediate structures with lifetimes in the millisecond time range at presently operational facilities. Third-generation storage rings which are under construction may permit one to reach a time resolution of one microsecond for non-cyclic and one nanosecond for cyclic reactions. The number of individual exposures required for exploring reciprocal space and hence the total time scale strongly depend on the lattice order that may be affected, e.g., by conformational changes. Time-resolved experiments require high population of a specific intermediate which has to be homogeneous over the crystal volume. A number of external excitation techniques have been developed including in situ liberation of active metabolites by laser pulse photolysis of photolabile inactive precursors. First applications to crystal structure analysis of catalytic intermediates of enzymes demonstrate the potential of time-resolved protein crystallography.

Resonant inelastic X-ray scattering on synthetic nickel compounds and Ni-Fe hydrogenase protein

NASA Astrophysics Data System (ADS)

Sanganas, Oliver; Löscher, Simone; Pfirrmann, Stefan; Marinos, Nicolas; Glatzel, Pieter; Weng, Tsu-Chien; Limberg, Christian; Driess, Matthias; Dau, Holger; Haumann, Michael

2009-11-01

Ni-Fe hydrogenases are proteins catalyzing the oxidative cleavage of dihydrogen (H2) and proton reduction to H2 at high turnover rates. Their active site is a heterobimetallic center comprising one Ni and one Fe atom. To understand the function of the site, well resolved structural and electronic information is required. Such information is expected to become accessible by high resolution X-ray absorption and emission techniques, which are rapidly developing at third generation synchrotron radiation sources. We studied a number of synthetic Ni compounds, which mimic relevant features of the Ni site in hydrogenases, and the Ni site in the soluble, NAD-reducing hydrogenase (SH) from the bacterium Ralstonia eutropha by resonant inelastic X-ray scattering (RIXS) using a Rowland-type spectrometer at the ESRF. The SH is particularly interesting because its H2-cleavage reaction is highly resistant against inhibition by O2. Kα-fluorescence detected RIXS planes in the 1s→3d region of the X-ray absorption spectrum were recorded on the protein which allow to extract L3-edge type spectra Spectral features of the protein are compared to those of the model compounds.

Thermal deformation of cryogenically cooled silicon crystals under intense X-ray beams: measurement and finite-element predictions of the surface shape

PubMed Central

Zhang, Lin; Sánchez del Río, Manuel; Monaco, Giulio; Detlefs, Carsten; Roth, Thomas; Chumakov, Aleksandr I.; Glatzel, Pieter

2013-01-01

X-ray crystal monochromators exposed to white-beam X-rays in third-generation synchrotron light sources are subject to thermal deformations that must be minimized using an adequate cooling system. A new approach was used to measure the crystal shape profile and slope of several cryogenically cooled (liquid nitrogen) silicon monochromators as a function of beam power in situ and under heat load. The method utilizes multiple angular scans across the Bragg peak (rocking curve) at various vertical positions of a narrow-gap slit downstream from the monochromator. When increasing the beam power, the surface of the liquid-nitrogen-cooled silicon crystal deforms from a concave shape at low heat load to a convex shape at high heat load, passing through an approximately flat shape at intermediate heat load. Finite-element analysis is used to calculate the crystal thermal deformations. The simulated crystal profiles and slopes are in excellent agreement with experiments. The parameters used in simulations, such as material properties, absorbed power distribution on the crystal and cooling boundary conditions, are described in detail as they are fundamental for obtaining accurate results. PMID:23765298

Hard X-ray Sources for the Mexican Synchrotron Project

NASA Astrophysics Data System (ADS)

Reyes-Herrera, Juan

2016-10-01

One of the principal tasks for the design of the Mexican synchrotron was to define the storage ring energy. The main criteria for choosing the energy come from studying the electromagnetic spectrum that can be obtained from the synchrotron, because the energy range of the spectrum that can be obtained will determine the applications available to the users of the future light source. Since there is a public demand of hard X-rays for the experiments in the synchrotron community users from Mexico, in this work we studied the emission spectra from some hard X-ray sources which could be the best options for the parameters of the present Mexican synchrotron design. The calculations of the flux and the brightness for one Bending Magnet and four Insertion Devices are presented; specifically, for a Superconducting Bending Magnet (SBM), a Superconducting Wiggler (SCW), an In Vacuum Short Period Undulator (IV-SPU), a Superconducting Undulator (SCU) and for a Cryogenic Permanent Magnet Undulator (CPMU). Two commonly available synchrotron radiation programs were used for the computation (XOP and SRW). From the results, it can be concluded that the particle beam energy from the current design is enough to have one or more sources of hard X-rays. Furthermore, a wide range of hard X-ray region can be covered by the analyzed sources, and the choice of each type should be based on the specific characteristics of the X-ray beam to perform the experiments at the involved beamline. This work was done within the project Fomix Conacyt-Morelos ”Plan Estrategico para la construccion y operación de un Sincrotron en Morelos” (224392).

Applications of synchrotron radiation to materials science: Diffraction imaging (topography) and microradiography

NASA Technical Reports Server (NTRS)

Kuriyama, Masao

1988-01-01

Synchrotron radiation sources are now available throughout the world. The use of hard X-ray radiation from these sources for materials science is described with emphasis on diffraction imaging for material characterization. With the availability of synchrotron radiation, real-time in situ measurements of dynamic microstructural phenomena have been started. This is a new area where traditional application of X-rays has been superseded. Examples are chosen from limited areas and are by no means exhaustive. The new emerging information will, no doubt, have great impact on materials science and engineering.

Support for Synchrotron Access by Environmental Scientists

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daly, Michael; Madden, Andrew; Palumbo, Anthony

2006-06-01

To support ERSP-funded scientists in all aspects of synchrotron-based research at the Advanced Photon Source (APS). This support comes in one or more of the following forms: (1) writing proposals to the APS General User (GU) program, (2) providing time at MRCAT/EnviroCAT beamlines via the membership of the Molecular Environmental Science (MES) Group in MRCAT/EnviroCAT, (3) assistance in experimental design and sample preparation, (4) support at the beamline during the synchrotron experiment, (5) analysis and interpretation of the synchrotron data, and (6) integration of synchrotron experimental results into manuscripts.

Physics of compact nonthermal sources. III - Energetic considerations. [electron synchrotron radiation

NASA Technical Reports Server (NTRS)

Burbidge, G. R.; Jones, T. W.; Odell, S. L.

1974-01-01

The energy content of the compact incoherent electron-synchrotron sources 3C 84, 3C 120, 3C 273, 3C 279, 3C 454.3, CTA 102, 3C 446, PKS 2134+004, VRO 42.22.01 and OJ 287 is calculated on the assumption that the low-frequency turnovers in the radio spectrum are due to self-absorption and that the electron distribution is isotropic. The dependence of the source parameters on various modifications of the standard assumptions is determined. These involve relativistic motions, alternate explanations for the low-frequency turnover, proton-synchrotron radiation, and distance to the source. The canonical interpretation is found to be accurate in many respects; some of the difficulties and ways of dealing with them are discussed in detail.

A Third Generation Water Bath Based Blackbody Source

PubMed Central

Fowler, Joel B.

1995-01-01

A third generation water bath based black-body source has been designed and constructed in the Radiometric Physics Division at the National Institute of Standards and Technology, Gaithersburg, MD. The goal of this work was to design a large aperture blackbody source with improved temporal stability and reproducibility compared with earlier designs, as well as improved ease of use. These blackbody sources operate in the 278 K to 353 K range with water temperature combined standard uncertainties of 3.5 mK to 7.8 mK. The calculated emissivity of these sources is 0.9997 with a relative standard uncertainty of 0.0003. With a 50 mm limiting aperture at the cavity; entrance, the emissivity increases to 0.99997. PMID:29151763

Introducing Synchrotrons Into the Classroom

ScienceCinema

Bloch, Ashley; Lanzirotti, Tony

2018-06-08

Brookhaven's Introducing Synchrotrons Into the Classroom (InSynC) program gives teachers and their students access to the National Synchrotron Light Source through a competitive proposal process. The first batch of InSynC participants included a group of students from Islip Middle School, who used the massive machine to study the effectiveness of different what filters.

Signature of inverse Compton emission from blazars

NASA Astrophysics Data System (ADS)

Gaur, Haritma; Mohan, Prashanth; Wierzcholska, Alicja; Gu, Minfeng

2018-01-01

Blazars are classified into high-, intermediate- and low-energy-peaked sources based on the location of their synchrotron peak. This lies in infra-red/optical to ultra-violet bands for low- and intermediate-peaked blazars. The transition from synchrotron to inverse Compton emission falls in the X-ray bands for such sources. We present the spectral and timing analysis of 14 low- and intermediate-energy-peaked blazars observed with XMM-Newton spanning 31 epochs. Parametric fits to X-ray spectra help constrain the possible location of transition from the high-energy end of the synchrotron to the low-energy end of the inverse Compton emission. In seven sources in our sample, we infer such a transition and constrain the break energy in the range 0.6-10 keV. The Lomb-Scargle periodogram is used to estimate the power spectral density (PSD) shape. It is well described by a power law in a majority of light curves, the index being flatter compared to general expectation from active galactic nuclei, ranging here between 0.01 and 1.12, possibly due to short observation durations resulting in an absence of long-term trends. A toy model involving synchrotron self-Compton and external Compton (EC; disc, broad line region, torus) mechanisms are used to estimate magnetic field strength ≤0.03-0.88 G in sources displaying the energy break and infer a prominent EC contribution. The time-scale for variability being shorter than synchrotron cooling implies steeper PSD slopes which are inferred in these sources.

X-rays from radio pulsars - The detection of PSR 1055-52

NASA Technical Reports Server (NTRS)

Cheng, A. F.; Helfand, D. J.

1983-01-01

The short-period pulsar PSR 1055-52 has been detected as a soft X-ray source in the course of an Einstein Observatory survey of radio pulsars. Its X-ray to radio luminosity ratio is about 10,000, although the X-rays are not modulated at the neutron star's rotation frequency. High spatial resolution observations suggest that a significant fraction of the emission comes from an extended region surrounding the pulsar. Several possible scenarios for the origin of both point and extended X-ray emission from isolated neutron stars are investigated: radiation from the hot stellar surface, from hot polar caps, and from an optically thick atmosphere, as well as from a circumstellar nebula emitting thermal bremsstrahlung or synchrotron radiation. It is concluded that the spatial, spectral, and temporal characteristics of this source are most consistent with a model in which relativistic particles generated by the pulsar are radiating synchrotron X-rays in the surrounding magnetic field; i.e., that PSR 1055 is embedded in a mini-Crab nebula. Observational tests of this hypothesis are suggested, and the implications of this result for pulsar evolution are briefly discussed.

PREFACE: 11th International Conference on X-ray Microscopy (XRM2012)

NASA Astrophysics Data System (ADS)

Xu, Hongjie; Wu, Ziyu; Tai, Renzhong

2013-10-01

The Eleventh International Conference on X-ray Microscopy (XRM2012) was held on 5-10 August 2012 at the Hope hotel in Shanghai. Historically, for the first time the XRM conference took place in China. The conference was jointly hosted by the Shanghai Synchrotron Radiation Facility (SSRF) and the National Synchrotron Radiation Laboratory (NSRL). The series of XRM conferences dates back to 1983 in Göttingen, Germany. Since the Zürich conference, XRM2008, it has been held every two years, showing its increasing popularity among the x-ray microscopy communities around the world. Research in the area of x-ray microscopy is advancing very fast with the development of synchrotron radiation techniques, especially the emergence of third generation light sources with low natural emittance which has significantly pushed forward the development of technologies and applications in this area. This has been fully demonstrated in presentations from this and previous XRM conferences. XRM2012 was attended by 295 people including 21 invited speakers, 53 contributing speakers, 55 students, and 13 industry exhibitors. Over 232 abstracts were submitted for oral or poster presentation and 56 original, peer-reviewed papers are published in these proceedings. The conference was sponsored by the Chinese Academy of Sciences (CAS) and the National Natural Science Foundation of China (11210301016/A0802), and three gold sponsors active in industrial and technological fields related to x-ray microscopy. An exhibition booth was offered free to Australia synchrotron, the host for XRM2014, to promote the next conference which will be held in Melbourne, Australia in 2014. An unforgettable memory for most conference participants might be the charming night cruise along Pujiang river which was part of the welcome reception on the first evening. The Werner Meyer-Ilse Award (WMIA) prize this year was awarded to Irene Zanette (TU-München) and Stephan Werner (HZB-Berlin), the former for her pioneering new work in high-sensitivity phase-contrast and dark-field (small-angle x-ray scattering) images, the latter for his outstanding accomplishments in the field of on-chip zone plate stacking. The location for the XRM2016 conference was voted for by all conference attendees, and Diamond Light Source in the United Kingdom was chosen. A tour of SSRF was attended by nearly 100 participants who got a close look at the seven beamlines in operation before the close of the meeting. We would like to thank all the participants for their active involvement and excellent contributions during the conference and poster session, and the International Program Committee for their guidance, and outstanding support of local organizating committee for a successful XRM2012. Hongjie Xu, Ziyu Wu and Renzhong Tai Proceeding Editors Logos Conference photograph The PDF file also contains a number of photographs taken at the conference and lists of committes and participants.

Negative ion source development at the cooler synchrotron COSY/Jülich

NASA Astrophysics Data System (ADS)

Felden, O.; Gebel, R.; Maier, R.; Prasuhn, D.

2013-02-01

The Nuclear Physics Institute at the Forschungszentrum Jülich, a member of the Helmholtz Association, conducts experimental and theoretical basic research in the field of hadron, particle, and nuclear physics. It operates the cooler synchrotron COSY, an accelerator and storage ring, which provides unpolarized and polarized proton and deuteron beams with beam momenta of up to 3.7 GeV/c. Main activities of the accelerator division are the design and construction of the high energy storage ring HESR, a synchrotron and part of the international FAIR project, and the operation and development of COSY with injector cyclotron and ion sources. Filament driven volume sources and a charge exchange colliding beams source, based on a nuclear polarized atomic beam source, provide unpolarized and polarized H- or D- routinely for more than 6500 hours/year. Within the Helmholtz Association's initiative Accelerator Research and Development, ARD, the existing sources at COSY, as well as new sources for future programs, are investigated and developed. The paper reports about these plans, improved pulsed beams from the volume sources and the preparation of a source for the ELENA project at CERN.

Theory of electromagnetic insertion devices and the corresponding synchrotron radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shumail, Muhammad; Tantawi, Sami G.

Permanent magnet insertion devices (IDs), which are the main radiation generating devices in synchrotron light sources and free-electron lasers, use a time-invariant but space-periodic magnetic field to wiggle relativistic electrons for short-wavelength radiation generation. Recently, a high power microwave based undulator has also been successfully demonstrated at SLAC which promises the advantage of dynamic tunability of radiation spectrum and polarization. Such IDs employ transverse elecromagnetic fields which are periodic in both space and time to undulate the electrons. In this paper we develop a detailed theory of the principle of electromagnetic IDs from first principles for both linear and circularmore » polarization modes. The electromagnetic equivalent definitions of undulator period (λ u) and undulator deflection parameter (K) are derived. In the inertial frame where the average momentum of the electron is zero, we obtain the figure-8-like trajectory for the linear polarization mode and the circular trajectory for the circular polarization mode. As a result, the corresponding radiation spectra and the intensity of harmonics is also calculated.« less

Theory of electromagnetic insertion devices and the corresponding synchrotron radiation

DOE PAGES

Shumail, Muhammad; Tantawi, Sami G.

2016-07-27

Permanent magnet insertion devices (IDs), which are the main radiation generating devices in synchrotron light sources and free-electron lasers, use a time-invariant but space-periodic magnetic field to wiggle relativistic electrons for short-wavelength radiation generation. Recently, a high power microwave based undulator has also been successfully demonstrated at SLAC which promises the advantage of dynamic tunability of radiation spectrum and polarization. Such IDs employ transverse elecromagnetic fields which are periodic in both space and time to undulate the electrons. In this paper we develop a detailed theory of the principle of electromagnetic IDs from first principles for both linear and circularmore » polarization modes. The electromagnetic equivalent definitions of undulator period (λ u) and undulator deflection parameter (K) are derived. In the inertial frame where the average momentum of the electron is zero, we obtain the figure-8-like trajectory for the linear polarization mode and the circular trajectory for the circular polarization mode. As a result, the corresponding radiation spectra and the intensity of harmonics is also calculated.« less

Synchrotron applications in wood preservation and deterioration

Treesearch

Barbara L. Illman

2003-01-01

Several non-intrusive synchrotron techniques are being used to detect and study wood decay. The techniques use high intensity synchrotron-generated X-rays to determine the atomic structure of materials with imaging, diffraction, and absorption. Some of the techniques are X-ray absorption near edge structure (XANES), X-ray fluorescence spectroscopy (XFS), X-ray...

LOFAR discovery of a double radio halo system in Abell 1758 and radio/X-ray study of the cluster pair

NASA Astrophysics Data System (ADS)

Botteon, A.; Shimwell, T. W.; Bonafede, A.; Dallacasa, D.; Brunetti, G.; Mandal, S.; van Weeren, R. J.; Brüggen, M.; Cassano, R.; de Gasperin, F.; Hoang, D. N.; Hoeft, M.; Röttgering, H. J. A.; Savini, F.; White, G. J.; Wilber, A.; Venturi, T.

2018-05-01

Radio halos and radio relics are diffuse synchrotron sources that extend over Mpc-scales and are found in a number of merger galaxy clusters. They are believed to form as a consequence of the energy that is dissipated by turbulence and shocks in the intra-cluster medium (ICM). However, the precise physical processes that generate these steep synchrotron spectrum sources are still poorly constrained. We present a new LOFAR observation of the double galaxy cluster Abell 1758. This system is composed of A1758N, a massive cluster hosting a known giant radio halo, and A1758S, which is a less massive cluster whose diffuse radio emission is confirmed here for the first time. Our observations have revealed a radio halo and a candidate radio relic in A1758S, and a suggestion of emission along the bridge connecting the two systems which deserves confirmation. We combined the LOFAR data with archival VLA and GMRT observations to constrain the spectral properties of the diffuse emission. We also analyzed a deep archival Chandra observation and used this to provide evidence that A1758N and A1758S are in a pre-merger phase. The ICM temperature across the bridge that connects the two systems shows a jump which might indicate the presence of a transversal shock generated in the initial stage of the merger.

National Synchrotron Light Source II

ScienceCinema

Hill, John; Dooryhee, Eric; Wilkins, Stuart; Miller, Lisa; Chu, Yong

2018-01-16

NSLS-II is a synchrotron light source helping researchers explore solutions to the grand energy challenges faced by the nation, and open up new regimes of scientific discovery that will pave the way to discoveries in physics, chemistry, and biology — advances that will ultimately enhance national security and help drive the development of abundant, safe, and clean energy technologies.

Synchrotron Radiation from Outer Space and the Chandra X-Ray Observatory

NASA Technical Reports Server (NTRS)

Weisskopf, M. C.

2006-01-01

The universe provides numerous extremely interesting astrophysical sources of synchrotron X radiation. The Chandra X-ray Observatory and other X-ray missions provide powerful probes of these and other cosmic X-ray sources. Chandra is the X-ray component of NASA's Great Observatory Program which also includes the Hubble Space telescope, the Spitzer Infrared Telescope Facility, and the now defunct Compton Gamma-Ray Observatory. The Chandra X-Ray Observatory provides the best angular resolution (sub-arcsecond) of any previous, current, or planned (for the foreseeable near future) space-based X-ray instrumentation. We present here a brief overview of the technical capability of this X-Ray observatory and some of the remarkable discoveries involving cosmic synchrotron sources.

The role of iron in neurodegenerative disorders: insights and opportunities with synchrotron light

PubMed Central

Collingwood, Joanna F.; Davidson, Mark R.

2014-01-01

There is evidence for iron dysregulation in many forms of disease, including a broad spectrum of neurodegenerative disorders. In order to advance our understanding of the pathophysiological role of iron, it is helpful to be able to determine in detail the distribution of iron as it relates to metabolites, proteins, cells, and tissues, the chemical state and local environment of iron, and its relationship with other metal elements. Synchrotron light sources, providing primarily X-ray beams accompanied by access to longer wavelengths such as infra-red, are an outstanding tool for multi-modal non-destructive analysis of iron in these systems. The micro- and nano-focused X-ray beams that are generated at synchrotron facilities enable measurement of iron and other transition metal elements to be performed with outstanding analytic sensitivity and specificity. Recent developments have increased the scope for methods such as X-ray fluorescence mapping to be used quantitatively rather than semi-quantitatively. Burgeoning interest, coupled with technical advances and beamline development at synchrotron facilities, has led to substantial improvements in resources and methodologies in the field over the past decade. In this paper we will consider how the field has evolved with regard to the study of iron in proteins, cells, and brain tissue, and identify challenges in sample preparation and analysis. Selected examples will be used to illustrate the contribution, and future potential, of synchrotron X-ray analysis for the characterization of iron in model systems exhibiting iron dysregulation, and for human cases of neurodegenerative disorders including Alzheimer’s disease, Parkinson’s disease, Friedreich’s ataxia, and amyotrophic lateral sclerosis. PMID:25191270

Chemical Crystallography at the Advanced Light Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCormick, Laura; Giordano, Nico; Teat, Simon

Chemical crystallography at synchrotrons was pioneered at the Daresbury SRS station 9.8. The chemical crystallography beamlines at the Advanced Light Source seek to follow that example, with orders of magnitude more flux than a lab source, and various in situ experiments. This article thus attempts to answer why a chemist would require synchrotron X-rays, to describe the techniques available at the ALS chemical crystallography beamlines, and place the current facilities in a historical context.

Chemical Crystallography at the Advanced Light Source

DOE PAGES

McCormick, Laura; Giordano, Nico; Teat, Simon; ...

2017-12-18

Chemical crystallography at synchrotrons was pioneered at the Daresbury SRS station 9.8. The chemical crystallography beamlines at the Advanced Light Source seek to follow that example, with orders of magnitude more flux than a lab source, and various in situ experiments. This article thus attempts to answer why a chemist would require synchrotron X-rays, to describe the techniques available at the ALS chemical crystallography beamlines, and place the current facilities in a historical context.

Scanning force microscope for in situ nanofocused X-ray diffraction studies

PubMed Central

Ren, Zhe; Mastropietro, Francesca; Davydok, Anton; Langlais, Simon; Richard, Marie-Ingrid; Furter, Jean-Jacques; Thomas, Olivier; Dupraz, Maxime; Verdier, Marc; Beutier, Guillaume; Boesecke, Peter; Cornelius, Thomas W.

2014-01-01

A compact scanning force microscope has been developed for in situ combination with nanofocused X-ray diffraction techniques at third-generation synchrotron beamlines. Its capabilities are demonstrated on Au nano-islands grown on a sapphire substrate. The new in situ device allows for in situ imaging the sample topography and the crystallinity by recording simultaneously an atomic force microscope (AFM) image and a scanning X-ray diffraction map of the same area. Moreover, a selected Au island can be mechanically deformed using the AFM tip while monitoring the deformation of the atomic lattice by nanofocused X-ray diffraction. This in situ approach gives access to the mechanical behavior of nanomaterials. PMID:25178002

Status of the Siberian synchrotron radiation center

NASA Astrophysics Data System (ADS)

Ancharov, A. I.; Baryshev, V. B.; Chernov, V. A.; Gentselev, A. N.; Goldenberg, B. G.; Kochubei, D. I.; Korchuganov, V. N.; Kulipanov, G. N.; Kuzin, M. V.; Levichev, E. B.; Mezentsev, N. A.; Mishnev, S. I.; Nikolenko, A. D.; Pindyurin, V. F.; Sheromov, M. A.; Tolochko, B. P.; Sharafutdinov, M. R.; Shmakov, A. N.; Vinokurov, N. A.; Vobly, P. D.; Zolotarev, K. V.

2005-05-01

Synchrotron radiation (SR) experiments at the Budker Institute of Nuclear Physics had been started in 1973, and from 1981 the Siberian Synchrotron Radiation Center (SSRC) had an official status as Research Center of the Russian Academy of Sciences. SSRC is the research center, which is open and free of tax for the research teams from Russia and abroad. In this report some technical information about the storage rings—SR sources of the Budker INP, the main directions of activity of SSRC, experimental stations, experimental works and users—is given. Development of the free electron lasers, new SR sources and insertion devices is described.

A NOVEL EMISSION SPECTRUM FROM A RELATIVISTIC ELECTRON MOVING IN A RANDOM MAGNETIC FIELD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teraki, Yuto; Takahara, Fumio, E-mail: teraki@vega.ess.sci.osaka-u.ac.jp

2011-07-10

We numerically calculate the radiation spectrum from relativistic electrons moving in small-scale turbulent magnetic fields expected in high-energy astrophysical sources. Such a radiation spectrum is characterized by the strength parameter a = {lambda}{sub B} e|B|/mc {sup 2}, where {lambda}{sub B} is the length scale of the turbulent field. When a is much larger than the Lorentz factor of a radiating electron {gamma}, synchrotron radiation is realized, while a << 1 corresponds to the so-called jitter radiation regime. Because for 1 < a < {gamma} we cannot use either approximations, we should have recourse to the Lienard-Wiechert potential to evaluate themore » radiation spectrum, which is performed in this Letter. We generate random magnetic fields assuming Kolmogorov turbulence, inject monoenergetic electrons, solve the equation of motion, and calculate the radiation spectrum. We perform numerical calculations for several values of a with {gamma} = 10. We obtain various types of spectra ranging between jitter radiation and synchrotron radiation. For a {approx} 7, the spectrum takes a novel shape which had not been noticed up to now. It is like a synchrotron spectrum in the middle energy region, but in the low frequency region it is a broken power law and in the high frequency region an extra power-law component appears beyond the synchrotron cutoff. We give a physical explanation of these features.« less

Using synchrotron light to accelerate EUV resist and mask materials learning

NASA Astrophysics Data System (ADS)

Naulleau, Patrick; Anderson, Christopher N.; Baclea-an, Lorie-Mae; Denham, Paul; George, Simi; Goldberg, Kenneth A.; Jones, Gideon; McClinton, Brittany; Miyakawa, Ryan; Mochi, Iacopo; Montgomery, Warren; Rekawa, Seno; Wallow, Tom

2011-03-01

As commercialization of extreme ultraviolet lithography (EUVL) progresses, direct industry activities are being focused on near term concerns. The question of long term extendibility of EUVL, however, remains crucial given the magnitude of the investments yet required to make EUVL a reality. Extendibility questions are best addressed using advanced research tools such as the SEMATECH Berkeley microfield exposure tool (MET) and actinic inspection tool (AIT). Utilizing Lawrence Berkeley National Laboratory's Advanced Light Source facility as the light source, these tools benefit from the unique properties of synchrotron light enabling research at nodes generations ahead of what is possible with commercial tools. The MET for example uses extremely bright undulator radiation to enable a lossless fully programmable coherence illuminator. Using such a system, resolution enhancing illuminations achieving k1 factors of 0.25 can readily be attained. Given the MET numerical aperture of 0.3, this translates to an ultimate resolution capability of 12 nm. Using such methods, the SEMATECH Berkeley MET has demonstrated resolution in resist to 16-nm half pitch and below in an imageable spin-on hard mask. At a half pitch of 16 nm, this material achieves a line-edge roughness of 2 nm with a correlation length of 6 nm. These new results demonstrate that the observed stall in ultimate resolution progress in chemically amplified resists is a materials issue rather than a tool limitation. With a resolution limit of 20-22 nm, the CAR champion from 2008 remains as the highest performing CAR tested to date. To enable continued advanced learning in EUV resists, SEMATECH has initiated a plan to implement a 0.5 NA microfield tool at the Advanced Light Source synchrotron facility. This tool will be capable of printing down to 8-nm half pitch.

High-resolution synchrotron-based Fourier transform spectroscopy of [image omitted] in the 120-350 cm-1 far-infrared region

NASA Astrophysics Data System (ADS)

Moruzzi, G.; Murphy, R. J.; Lees, R. M.; Predoi-Cross, A.; Billinghurst, B. E.

2010-09-01

The Fourier transform spectrum of the ? isotopologue of methanol has been recorded in the 120-350 cm-1 far-infrared region at a resolution of 0.00096 cm-1 using synchrotron source radiation at the Canadian Light Source. The study, motivated by astrophysical applications, is aimed at generating a sufficiently accurate set of energy level term values for the ground vibrational state to allow prediction of the centres of the quadrupole hyperfine multiplets for astronomically observable sub-millimetre transitions to within an uncertainty of a few MHz. To expedite transition identification, a new function was added to the Ritz program in which predicted spectral line positions were generated by an adjustable interpolation between the known assignments for the ? and ? isotopologues. By displaying the predictions along with the experimental spectrum on the computer monitor and adjusting the predictions to match observed features, rapid assignment of numerous ? sub-bands was possible. The least squares function of the Ritz program was then used to generate term values for the identified levels. For each torsion-K-rotation substate, the term values were fitted to a Taylor-series expansion in powers of J(J + 1) to determine the substate origin energy and effective B-value. In this first phase of the study we did not attempt a full global fit to the assigned transitions, but instead fitted the sub-band J-independent origins to a restricted Hamiltonian containing the principal torsional and K-dependent terms. These included structural and torsional potential parameters plus quartic distortional and torsion-rotation interaction terms.

SYNCHROTRON HEATING BY A FAST RADIO BURST IN A SELF-ABSORBED SYNCHROTRON NEBULA AND ITS OBSERVATIONAL SIGNATURE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Yuan-Pei; Dai, Zi-Gao; Zhang, Bing, E-mail: zhang@physics.unlv.edu

Fast radio bursts (FRBs) are mysterious transient sources. If extragalactic, as suggested by their relative large dispersion measures, their brightness temperatures must be extremely high. Some FRB models (e.g., young pulsar model, magnetar giant flare model, or supra-massive neutron star collapse model) suggest that they may be associated with a synchrotron nebula. Here we study a synchrotron-heating process by an FRB in a self-absorbed synchrotron nebula. If the FRB frequency is below the synchrotron self-absorption frequency of the nebula, electrons in the nebula would absorb FRB photons, leading to a harder electron spectrum and enhanced self-absorbed synchrotron emission. In themore » meantime, the FRB flux is absorbed by the nebula electrons. We calculate the spectra of FRB-heated synchrotron nebulae, and show that the nebula spectra would show a significant hump in several decades near the self-absorption frequency. Identifying such a spectral feature would reveal an embedded FRB in a synchrotron nebula.« less

Main functions, recent updates, and applications of Synchrotron Radiation Workshop code

NASA Astrophysics Data System (ADS)

Chubar, Oleg; Rakitin, Maksim; Chen-Wiegart, Yu-Chen Karen; Chu, Yong S.; Fluerasu, Andrei; Hidas, Dean; Wiegart, Lutz

2017-08-01

The paper presents an overview of the main functions and new application examples of the "Synchrotron Radiation Workshop" (SRW) code. SRW supports high-accuracy calculations of different types of synchrotron radiation, and simulations of propagation of fully-coherent radiation wavefronts, partially-coherent radiation from a finite-emittance electron beam of a storage ring source, and time-/frequency-dependent radiation pulses of a free-electron laser, through X-ray optical elements of a beamline. An extended library of physical-optics "propagators" for different types of reflective, refractive and diffractive X-ray optics with its typical imperfections, implemented in SRW, enable simulation of practically any X-ray beamline in a modern light source facility. The high accuracy of calculation methods used in SRW allows for multiple applications of this code, not only in the area of development of instruments and beamlines for new light source facilities, but also in areas such as electron beam diagnostics, commissioning and performance benchmarking of insertion devices and individual X-ray optical elements of beamlines. Applications of SRW in these areas, facilitating development and advanced commissioning of beamlines at the National Synchrotron Light Source II (NSLS-II), are described.

From synchrotron radiation to lab source: advanced speckle-based X-ray imaging using abrasive paper

NASA Astrophysics Data System (ADS)

Wang, Hongchang; Kashyap, Yogesh; Sawhney, Kawal

2016-02-01

X-ray phase and dark-field imaging techniques provide complementary and inaccessible information compared to conventional X-ray absorption or visible light imaging. However, such methods typically require sophisticated experimental apparatus or X-ray beams with specific properties. Recently, an X-ray speckle-based technique has shown great potential for X-ray phase and dark-field imaging using a simple experimental arrangement. However, it still suffers from either poor resolution or the time consuming process of collecting a large number of images. To overcome these limitations, in this report we demonstrate that absorption, dark-field, phase contrast, and two orthogonal differential phase contrast images can simultaneously be generated by scanning a piece of abrasive paper in only one direction. We propose a novel theoretical approach to quantitatively extract the above five images by utilising the remarkable properties of speckles. Importantly, the technique has been extended from a synchrotron light source to utilise a lab-based microfocus X-ray source and flat panel detector. Removing the need to raster the optics in two directions significantly reduces the acquisition time and absorbed dose, which can be of vital importance for many biological samples. This new imaging method could potentially provide a breakthrough for numerous practical imaging applications in biomedical research and materials science.

Laboratory Directed Research and Development Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogeka, G.J.; Romano, A.J.

This report briefly discusses the following research: Advances in Geoexploration; Transvenous Coronary Angiography with Synchrotron X-Rays; Borehole Measurements of Global Warming; Molecular Ecology: Development of Field Methods for Microbial Growth Rate and Activity Measurements; A New Malaria Enzyme - A Potential Source for a New Diagnostic Test for Malaria and a Target for a New Antimalarial Drug; Basic Studies on Thoron and Thoron Precursors; Cloning of the cDNA for a Human Serine/Threonine Protein Kinase that is Activated Specifically by Double-Stranded DNA; Development of an Ultra-Fast Laser System for Accelerator Applications; Cluster Impact Fusion; Effect of a Bacterial Spore Protein onmore » Mutagenesis; Structure and Function of Adenovirus Penton Base Protein; High Resolution Fast X-Ray Detector; Coherent Synchrotron Radiation Longitudinal Bunch Shape Monitor; High Grain Harmonic Generation Experiment; BNL Maglev Studies; Structural Investigations of Pt-Based Catalysts; Studies on the Cellular Toxicity of Cocaine and Cocaethylene; Human Melanocyte Transformation; Exploratory Applications of X-Ray Microscopy; Determination of the Higher Ordered Structure of Eukaryotic Chromosomes; Uranium Neutron Capture Therapy; Tunneling Microscopy Studies of Nanoscale Structures; Nuclear Techiques for Study of Biological Channels; RF Sources for Accelerator Physics; Induction and Repair of Double-Strand Breaks in the DNA of Human Lymphocytes; and An EBIS Source of High Charge State Ions up to Uranium.« less

Laboratory Directed Research and Development Program. Annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogeka, G.J.; Romano, A.J.

This report briefly discusses the following research: Advances in Geoexploration; Transvenous Coronary Angiography with Synchrotron X-Rays; Borehole Measurements of Global Warming; Molecular Ecology: Development of Field Methods for Microbial Growth Rate and Activity Measurements; A New Malaria Enzyme - A Potential Source for a New Diagnostic Test for Malaria and a Target for a New Antimalarial Drug; Basic Studies on Thoron and Thoron Precursors; Cloning of the cDNA for a Human Serine/Threonine Protein Kinase that is Activated Specifically by Double-Stranded DNA; Development of an Ultra-Fast Laser System for Accelerator Applications; Cluster Impact Fusion; Effect of a Bacterial Spore Protein onmore » Mutagenesis; Structure and Function of Adenovirus Penton Base Protein; High Resolution Fast X-Ray Detector; Coherent Synchrotron Radiation Longitudinal Bunch Shape Monitor; High Grain Harmonic Generation Experiment; BNL Maglev Studies; Structural Investigations of Pt-Based Catalysts; Studies on the Cellular Toxicity of Cocaine and Cocaethylene; Human Melanocyte Transformation; Exploratory Applications of X-Ray Microscopy; Determination of the Higher Ordered Structure of Eukaryotic Chromosomes; Uranium Neutron Capture Therapy; Tunneling Microscopy Studies of Nanoscale Structures; Nuclear Techiques for Study of Biological Channels; RF Sources for Accelerator Physics; Induction and Repair of Double-Strand Breaks in the DNA of Human Lymphocytes; and An EBIS Source of High Charge State Ions up to Uranium.« less

Reciprocal Space Mapping of Macromolecular Crystals in the Home Laboratory

NASA Technical Reports Server (NTRS)

Snell, Edward H.; Fewster, P. F.; Andrew, Norman; Boggon, T. J.; Judge, Russell A.; Pusey, Marc A.

1999-01-01

Reciprocal space mapping techniques are used widely by the materials science community to provide physical information about their crystal samples. We have used similar methods at synchrotron sources to look at the quality of macromolecular crystals produced both on the ground and under microgravity conditions. The limited nature of synchrotron time has led us to explore the use of a high resolution materials research diffractometer to perform similar measurements in the home laboratory. Although the available intensity is much reduced due to the beam conditioning necessary for high reciprocal space resolution, lower resolution data can be collected in the same detail as the synchrotron source. Experiments can be optimized at home to make most benefit from the synchrotron time available. Preliminary results including information on the mosaicity and the internal strains from reciprocal space maps will be presented.

Synchrotron cooling and annihilation of an e/+/-e/-/ plasma - The radiation mechanism for the 5 March, 1979 transient

NASA Technical Reports Server (NTRS)

Ramaty, R.; Bussard, R. W.; Lingenfelter, R. E.

1981-01-01

Positron-electron pair radiation is examined as a mechanism that could be responsible for the impulsive phase emission of the 5 March, 1979 transient. Synchrotron cooling and subsequent annihilation of the pairs can account for the energy spectrum, the very high brightness, and the 0.4 MeV feature observed from this transient, whose source is likely to be a neutron star in the supernova remnant N49 in the Large Magellanic Cloud. In this model, the observed radiation is produced in the skin layer of a hot, radiation-dominated pair atmosphere, probably confined to the vicinity of the neutron star by a strong magnetic field. In this layer, about 10 to the 12th generations of pairs are formed (by photon-photon collisions), cooled and annihilated during the 0.15 s duration of the impulsive phase.

Measurement of Cosmic-Ray TeV Electrons

NASA Astrophysics Data System (ADS)

Schubnell, Michael; Anderson, T.; Bower, C.; Coutu, S.; Gennaro, J.; Geske, M.; Mueller, D.; Musser, J.; Nutter, S.; Park, N.; Tarle, G.; Wakely, S.

2011-09-01

The Cosmic Ray Electron Synchrotron Telescope (CREST) high-altitude balloon experiment is a pathfinding effort to detect for the first time multi-TeV cosmic-ray electrons. At these energies distant sources will not contribute to the local electron spectrum due to the strong energy losses of the electrons and thus TeV observations will reflect the distribution and abundance of nearby acceleration sites. CREST will detect electrons indirectly by measuring the characteristic synchrotron photons generated in the Earth's magnetic field. The instrument consist of an array of 1024 BaF2 crystals viewed by photomultiplier tubes surrounded by a hermetic scintillator shield. Since the primary electron itself need not traverse the payload, an effective detection area is achieved that is several times the nominal 6.4 m2 instrument. CREST is scheduled to fly in a long duration circumpolar orbit over Antarctica during the 2011-12 season.

Comparison of diffraction-enhanced computed tomography and monochromatic synchrotron radiation computed tomography of human trabecular bone.

PubMed

Connor, D M; Hallen, H D; Lalush, D S; Sumner, D R; Zhong, Z

2009-10-21

Diffraction-enhanced imaging (DEI) is an x-ray-based medical imaging modality that, when used in tomography mode (DECT), can generate a three-dimensional map of both the apparent absorption coefficient and the out-of-plane gradient of the index of refraction of the sample. DECT is known to have contrast gains over monochromatic synchrotron radiation CT (SRCT) for soft tissue structures. The goal of this experiment was to compare contrast-to-noise ratio (CNR) and resolution in images of human trabecular bone acquired using SRCT with images acquired using DECT. All images were acquired at the National Synchrotron Light Source (Upton, NY, USA) at beamline X15 A at an x-ray energy of 40 keV and the silicon [3 3 3] reflection. SRCT, apparent absorption DECT and refraction DECT slice images of the trabecular bone were created. The apparent absorption DECT images have significantly higher spatial resolution and CNR than the corresponding SRCT images. Thus, DECT will prove to be a useful tool for imaging applications in which high contrast and high spatial resolution are required for both soft tissue features and bone.

Synchrotron X-Ray Diffraction Analysis of Meteorites in Thin Section: Preliminary Results

NASA Technical Reports Server (NTRS)

Treiman, A. H.; Lanzirotti, A.; Xirouchakis, D.

2004-01-01

X-ray diffraction is the pre-eminent technique for mineral identification and structure determination, but is difficult to apply to grains in thin section, the standard meteorite preparation. Bright focused X-ray beams from synchrotrons have been used extensively in mineralogy and have been applied to extraterrestrial particles. The intensity and small spot size achievable in synchrotron X-ray beams makes them useful for study of materials in thin sections. Here, we describe Synchrotron X-ray Diffraction (SXRD) in thin section as done at the National Synchrotron Light Source, and cite examples of its value for studies of meteorites in thin section.

Real time observation of mouse fetal skeleton using a high resolution X-ray synchrotron

PubMed Central

Chang, Dong Woo; Kim, Bora; Shin, Jae Hoon; Yun, Young Min; Je, Jung Ho; Hwu, Yeu kuang; Yoon, Jung Hee

2011-01-01

The X-ray synchrotron is quite different from conventional radiation sources. This technique may expand the capabilities of conventional radiology and be applied in novel manners for special cases. To evaluate the usefulness of X-ray synchrotron radiation systems for real time observations, mouse fetal skeleton development was monitored with a high resolution X-ray synchrotron. A non-monochromatized X-ray synchrotron (white beam, 5C1 beamline) was employed to observe the skeleton of mice under anesthesia at embryonic day (E)12, E14, E15, and E18. At the same time, conventional radiography and mammography were used to compare with X-ray synchrotron. After synchrotron radiation, each mouse was sacrificed and stained with Alizarin red S and Alcian blue to observe bony structures. Synchrotron radiation enabled us to view the mouse fetal skeleton beginning at gestation. Synchrotron radiation systems facilitate real time observations of the fetal skeleton with greater accuracy and magnification compared to mammography and conventional radiography. Our results show that X-ray synchrotron systems can be used to observe the fine structures of internal organs at high magnification. PMID:21586868

Gas bremsstrahlung shielding calculation for first optic enclosure of ILSF medical beamline

NASA Astrophysics Data System (ADS)

Beigzadeh Jalali, H.; Salimi, E.; Rahighi, J.

2016-10-01

Gas bremsstrahlung is generated in high energy electron storage ring accompanies the synchrotron radiation into the beamlines and strike the various components of the beamline. In this paper, radiation shielding calculation for secondary gas bremsstrahlung is performed for the first optics enclosure (FOE) of medical beamline of the Iranian Light Source Facility (ILSF). Dose equivalent rate (DER) calculation is accomplished using FLUKA Monte Carlo code. A comprehensive study of DER distribution at the back wall, sides and roof is given.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borland, M.; Hettel, R.; Leemann, S. C.

With the recent success in commissioning of MAX IV, the multi-bend achromat (MBA) lattice has begun to deliver on its promise to usher in a new generation of higher-brightness synchrotron light sources. In this paper, we begin by reviewing the challenges, recent success, and lessons learned of the MAX-IV project. Drawing on these lessons, we then describe the physics challenges in even more ambitious rings and how these can be met. In addition, we touch on engineering issues and choices that are tightly linked with the physics design.

Hierarchical multimodal tomographic x-ray imaging at a superbend

NASA Astrophysics Data System (ADS)

Stampanoni, M.; Marone, F.; Mikuljan, G.; Jefimovs, K.; Trtik, P.; Vila-Comamala, J.; David, C.; Abela, R.

2008-08-01

Over the last decade, synchrotron-based X-ray tomographic microscopy has established itself as a fundamental tool for non-invasive, quantitative investigations of a broad variety of samples, with application ranging from space research and materials science to biology and medicine. Thanks to the brilliance of modern third generation sources, voxel sizes in the micrometer range are routinely achieved by the major X-ray microtomography devices around the world, while the isotropic 100 nm barrier is reached and trespassed only by few instruments. The beamline for TOmographic Microscopy and Coherent rAdiology experiments (TOMCAT) of the Swiss Light Source at the Paul Scherrer Institut, operates a multimodal endstation which offers tomographic capabilities in the micrometer range in absorption contrast - of course - as well as phase contrast imaging. Recently, the beamline has been equipped with a full field, hard X-rays microscope with a theoretical pixel size down to 30 nm and a field of view of 50 microns. The nanoscope performs well at X-ray energies between 8 and 12 keV, selected from the white beam of a 2.9 T superbend by a [Ru/C]100 fixed exit multilayer monochromator. In this work we illustrate the experimental setup dedicated to the nanoscope, in particular the ad-hoc designed X-ray optics needed to produce a homogeneous, square illumination of the sample imaging plane as well as the magnifying zone plate. Tomographic reconstructions at 60 nm voxel size will be shown and discussed.

1WHSP: An IR-based sample of ~1000 VHE γ -ray blazar candidates

DOE PAGES

Arsioli, B.; Fraga, B.; Giommi, P.; ...

2015-06-23

Context. Blazars are the dominant type of extragalactic sources at microwave and at γ-ray energies. In the most energetic part of the electromagnetic spectrum (E > ≳ 100 GeV) a large fraction of high Galactic latitude sources are blazars of the High Synchrotron Peaked (HSP) type, that is BL Lac objects with synchrotron power peaking in the UV or in the X-ray band. Building new large samples of HSP blazars is key to understand the properties of jets under extreme conditions, and to study the demographics and the peculiar cosmological evolution of these sources. Aims. HSP blazars are remarkably rare,more » with only a few hundreds of them expected to be above the sensitivity limits of currently available surveys, some of which include hundreds of millions of sources. To find these very uncommon objects, we have devised a method that combines ALLWISE survey data with multi-frequency selection criteria. Methods. The sample was defined starting from a primary list of infrared colour-colour selected sources from the ALLWISE all sky survey database, and applying further restrictions on IR-radio and IR-X-ray flux ratios. Using a polynomial fit to the multi-frequency data (radio to X-ray) we estimated synchrotron peak frequencies and fluxes of each object. Results. We assembled a sample including 992 sources, which is currently the largest existing list of confirmed and candidates HSP blazars. All objects are expected to radiate up to the highest γ-ray photon energies. In fact, 299 of these are confirmed emitters of GeV γ-ray photons (based on Fermi-LAT catalogues), and 36 have already been detected in the TeV band. The majority of sources in the sample are within reach of the upcoming Cherenkov Telescope Array (CTA), and many may be detectable even by the current generation of Cherenkov telescopes during flaring episodes. The sample includes 425 previously known blazars, 151 new identifications, and 416 HSP candidates (mostly faint sources) for which no optical spectra is available yet. The full 1WHSP catalogue is on-line at http://www.asdc.asi.it/1whsp/ providing a direct link to the SED building tool where multifrequency data for each source can be easily visualised.« less

Structural Genomics and Drug Discovery for Infectious Diseases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, W.F.

The application of structural genomics methods and approaches to proteins from organisms causing infectious diseases is making available the three dimensional structures of many proteins that are potential drug targets and laying the groundwork for structure aided drug discovery efforts. There are a number of structural genomics projects with a focus on pathogens that have been initiated worldwide. The Center for Structural Genomics of Infectious Diseases (CSGID) was recently established to apply state-of-the-art high throughput structural biology technologies to the characterization of proteins from the National Institute for Allergy and Infectious Diseases (NIAID) category A-C pathogens and organisms causing emerging,more » or re-emerging infectious diseases. The target selection process emphasizes potential biomedical benefits. Selected proteins include known drug targets and their homologs, essential enzymes, virulence factors and vaccine candidates. The Center also provides a structure determination service for the infectious disease scientific community. The ultimate goal is to generate a library of structures that are available to the scientific community and can serve as a starting point for further research and structure aided drug discovery for infectious diseases. To achieve this goal, the CSGID will determine protein crystal structures of 400 proteins and protein-ligand complexes using proven, rapid, highly integrated, and cost-effective methods for such determination, primarily by X-ray crystallography. High throughput crystallographic structure determination is greatly aided by frequent, convenient access to high-performance beamlines at third-generation synchrotron X-ray sources.« less

Challenges for Synchrotron X-Ray Optics

NASA Astrophysics Data System (ADS)

Freund, Andreas K.

2002-12-01

It is the task of x-ray optics to adapt the raw beam generated by modern sources such as synchrotron storage rings to a great variety of experimental requirements in terms of intensity, spot size, polarization and other parameters. The very high quality of synchrotron radiation (source size of a few microns and beam divergence of a few micro-radians) and the extreme x-ray flux (power of several hundred Watts in a few square mm) make this task quite difficult. In particular the heat load aspect is very important in the conditioning process of the brute x-ray power to make it suitable for being used on the experimental stations. Cryogenically cooled silicon crystals and water-cooled diamond crystals can presently fulfill this task, but limits will soon be reached and new schemes and materials must be envisioned. A major tendency of instrument improvement has always been to concentrate more photons into a smaller spot utilizing a whole variety of focusing devices such as Fresnel zone plates, refractive lenses and systems based on bent surfaces, for example, Kirkpatrick-Baez systems. Apart from the resistance of the sample, the ultimate limits are determined by the source size and strength on one side, by materials properties, cooling, mounting and bending schemes on the other side, and fundamentally by the diffraction process. There is also the important aspect of coherence that can be both a nuisance and a blessing for the experiments, in particular for imaging techniques. Its conservation puts additional constraints on the quality of the optical elements. The overview of the present challenges includes the properties of present and also mentions aspects of future x-ray sources such as the "ultimate" storage ring and free electron lasers. These challenges range from the thermal performances of monochromators to the surface quality of mirrors, from coherence preservation of modern multilayers to short pulse preservation by crystals, and from micro- and nano-focusing techniques to the accuracy and stability of mechanical supports.

Low-pressure Structural Modification of Aluminum Hydride

DTIC Science & Technology

2011-02-01

Acknowledgments Use of the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory ( BNL ) was supported by the U.S. Department of Energy...National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory ( BNL ). The spectral resolution of ±4 cm–1 was used for all IR measurements...12 List of Symbols, Abbreviations, and Acronyms Al aluminum AlH3 aluminum hydride BNL Brookhaven National Laboratory EOS equation of

MICROANALYSIS OF MATERIALS USING SYNCHROTRON RADIATION.

DOE Office of Scientific and Technical Information (OSTI.GOV)

JONES,K.W.; FENG,H.

2000-12-01

High intensity synchrotron radiation produces photons with wavelengths that extend from the infrared to hard x rays with energies of hundreds of keV with uniquely high photon intensities that can be used to determine the composition and properties of materials using a variety of techniques. Most of these techniques represent extensions of earlier work performed with ordinary tube-type x-ray sources. The properties of the synchrotron source such as the continuous range of energy, high degree of photon polarization, pulsed beams, and photon flux many orders of magnitude higher than from x-ray tubes have made possible major advances in the possiblemore » chemical applications. We describe here ways that materials analyses can be made using the high intensity beams for measurements with small beam sizes and/or high detection sensitivity. The relevant characteristics of synchrotron x-ray sources are briefly summarized to give an idea of the x-ray parameters to be exploited. The experimental techniques considered include x-ray fluorescence, absorption, and diffraction. Examples of typical experimental apparatus used in these experiments are considered together with descriptions of actual applications.« less

The angular power spectrum measurement of the Galactic synchrotron emission using the TGSS survey

NASA Astrophysics Data System (ADS)

Choudhuri, Samir; Bharadwaj, Somnath; Ali, Sk. Saiyad; Roy, Nirupam; Intema, H. T.; Ghosh, Abhik

2018-05-01

Characterizing the diffuse Galactic synchrotron emission (DGSE) at arcminute angular scales is needed to remove this foregrounds in cosmological 21-cm measurements. Here, we present the angular power spectrum (Cl) measurement of the diffuse Galactic synchrotron emission using two fields observed by the TIFR GMRT Sky Survey (TGSS). We apply 2D Tapered Gridded Estimator (TGE) to estimate the Cl from the visibilities. We find that the residual data after subtracting the point sources is likely dominated by the diffuse Galactic synchrotron radiation across the angular multipole range 240 <= l <~ 500. We fit a power law to the measured Cl over this l range. We find that the slopes in both fields are consistent with earlier measurements. For the second field, however, we interpret the measured Cl as an upper limit for the DGSE as there is an indication of a significant residual point source contribution.

CCD sensors in synchrotron X-ray detectors

NASA Astrophysics Data System (ADS)

Strauss, M. G.; Naday, I.; Sherman, I. S.; Kraimer, M. R.; Westbrook, E. M.; Zaluzec, N. J.

1988-04-01

The intense photon flux from advanced synchrotron light sources, such as the 7-GeV synchrotron being designed at Argonne, require integrating-type detectors. Charge-coupled devices (CCDs) are well suited as synchrotron X-ray detectors. When irradiated indirectly via a phosphor followed by reducing optics, diffraction patterns of 100 cm 2 can be imaged on a 2 cm 2 CCD. With a conversion efficiency of ˜ 1 CCD electron/X-ray photon, a peak saturation capacity of > 10 6 X-rays can be obtained. A programmable CCD controller operating at a clock frequency of 20 MHz has been developed. The readout rate is 5 × 10 6 pixels/s and the shift rate in the parallel registers is 10 6 lines/s. The test detector was evaluated in two experiments. In protein crystallography diffraction patterns have been obtained from a lysozyme crystal using a conventional rotating anode X-ray generator. Based on these results we expect to obtain at a synchrotron diffraction images at a rate of ˜ 1 frame/s or a complete 3-dimensional data set from a single crystal in ˜ 2 min. In electron energy-loss spectroscopy (EELS), the CCD was used in a parallel detection mode which is similar to the mode array detectors are used in dispersive EXAFS. With a beam current corresponding to 3 × 10 9 electron/s on the detector, a series of 64 spectra were recorded on the CCD in a continuous sequence without interruption due to readout. The frame-to-frame pixel signal fluctuations had σ = 0.4% from which DQE = 0.4 was obtained, where the detector conversion efficiency was 2.6 CCD electrons/X-ray photon. These multiple frame series also showed the time-resolved modulation of the electron microscope optics by stray magnetic fields.

Commission of a new 2-color laser-synchrotron COLTRIMS experiment

NASA Astrophysics Data System (ADS)

Gatton, A.; Larsen, K.; Champenois, E.; Shivaram, N.; Bakhti, S.; Iskander, W.; Sievert, T.; Reedy, D.; Weller, M.; Williams, J. B.; Landers, A.; Weber, Th.

2017-04-01

We present the technical scheme of a new 2-color laser + synchrotron Cold Target Recoil Ion Momentum Spectrometer (COLTRIMS) experiment in which we overlap a pulsed IR laser (1 MHz , 1030 nm , 12 ps , 5 *1011 W / cm2) with XUV light from beamline 10.0.1 (3 MHz , 18 . 56 eV , 80 ps , 50 meV resolution) at the Advanced Light Source (ALS) at Lawrence Berkeley National Lab. We discuss the experimental methods for overlapping in 3D the co-linear ALS beam (80 um × 100 um) with the laser beam focus (50 um × 50 um) inside the gas jet target with a horizontal length and depth of 1 mm , as well as the timing scheme for achieving sub nanosecond stable synchrolock of the two pulse trains such that they are overlapped in time at the gas jet target every third ALS pulse. We present a definitive 2 color signal observed in Helium excited by 23 . 74 eV photons from the ALS to the 1s4p 1P state, and then ionized by the laser. We intend to use this scheme to study dissociation dynamics of excited molecules in the presence of a strong laser field. This research used the Advanced Light Source and was supported by DOE-BES under Contract No. DE-AC02-05CH11231 and DE-FG02-86ER13491, the ALS Doctoral Fellowship in Residence, and the DFG and DAAD.

Optimizing a synchrotron based x-ray lithography system for IC manufacturing

NASA Astrophysics Data System (ADS)

Kovacs, Stephen; Speiser, Kenneth; Thaw, Winston; Heese, Richard N.

1990-05-01

The electron storage ring is a realistic solution as a radiation source for production grade, industrial X-ray lithography system. Today several large scale plans are in motion to design and implement synchrotron storage rings of different types for this purpose in the USA and abroad. Most of the scientific and technological problems related to the physics, design and manufacturing engineering, and commissioning of these systems for microlithography have been resolved or are under extensive study. However, investigation on issues connected to application of Synchrotron Orbit Radiation (SOR ) in chip production environment has been somewhat neglected. In this paper we have filled this gap pointing out direct effects of some basic synchrotron design parameters and associated subsystems (injector, X-ray beam line) on the operation and cost of lithography in production. The following factors were considered: synchrotron configuration, injection energy, beam intensity variability, number of beam lines and wafer exposure concept. A cost model has been worked out and applied to three different X-ray Lithography Source (XLS) systems. The results of these applications are compared and conclusions drawn.

Single-bunch synchrotron shutter

DOEpatents

Norris, James R.; Tang, Jau-Huei; Chen, Lin; Thurnauer, Marion

1993-01-01

An apparatus for selecting a single synchrotron pulse from the millions of pulses provided per second from a synchrotron source includes a rotating spindle located in the path of the synchrotron pulses. The spindle has multiple faces of a highly reflective surface, and having a frequency of rotation f. A shutter is spaced from the spindle by a radius r, and has an open position and a closed position. The pulses from the synchrotron are reflected off the spindle to the shutter such that the speed s of the pulses at the shutter is governed by: s=4.times..pi..times.r.times.f. such that a single pulse is selected for transmission through an open position of the shutter.

Fundamentals of Coherent Synchrotron Radiation in Storage Rings

NASA Astrophysics Data System (ADS)

Sannibale, F.; Byrd, J. M.; Loftsdottir, A.; Martin, M. C.; Venturini, M.

2004-05-01

We present the fundamental concepts for producing stable broadband coherent synchrotron radiation (CSR) in the terahertz frequency region in an electron storage ring. The analysis includes distortion of bunch shape from the synchrotron radiation (SR), enhancing higher frequency coherent emission and limits to stable emission due to a microbunching instability excited by the SR. We use these concepts to optimize the performance of a source for CSR emission.

Rigorous mathematical modelling for a Fast Corrector Power Supply in TPS

NASA Astrophysics Data System (ADS)

Liu, K.-B.; Liu, C.-Y.; Chien, Y.-C.; Wang, B.-S.; Wong, Y. S.

2017-04-01

To enhance the stability of beam orbit, a Fast Orbit Feedback System (FOFB) eliminating undesired disturbances was installed and tested in the 3rd generation synchrotron light source of Taiwan Photon Source (TPS) of National Synchrotron Radiation Research Center (NSRRC). The effectiveness of the FOFB greatly depends on the output performance of Fast Corrector Power Supply (FCPS); therefore, the design and implementation of an accurate FCPS is essential. A rigorous mathematical modelling is very useful to shorten design time and improve design performance of a FCPS. A rigorous mathematical modelling derived by the state-space averaging method for a FCPS in the FOFB of TPS composed of a full-bridge topology is therefore proposed in this paper. The MATLAB/SIMULINK software is used to construct the proposed mathematical modelling and to conduct the simulations of the FCPS. Simulations for the effects of the different resolutions of ADC on the output accuracy of the FCPS are investigated. A FCPS prototype is realized to demonstrate the effectiveness of the proposed rigorous mathematical modelling for the FCPS. Simulation and experimental results show that the proposed mathematical modelling is helpful for selecting the appropriate components to meet the accuracy requirements of a FCPS.

X-rays from radio pulsars: the detection of PSR 1055-52

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, A.F.; Helfand, D.J.

The short-period pulsar PSR 1055-52 has been detected as a soft X-ray source in the course of an Einstein Observatory survey of radio pulsars. Its X-ray to radio luminosity ratio is approx.10/sup 4/, although the X-rays are not modulated at the neutron star's rotation frequency. We present high spatial resolution observations which suggest that a significant fraction of the emission comes from an extended region surrounding the pulsar. We investigate several possible scenarios for the origin of both point and extended X-ray emission from isolated neutron stars: radiation from the hot stellar surface, from hot polar caps, and from anmore » optically thick atmosphere, as well as from a circumstellar nebula emitting thermal bremsstrahlung or synchrotron radiation. We conclude that the spatial, spectral, and temporal characteristic of this source are most consistent with a model in which relativistic particles generated by the pulsar are radiating synchrotron X-rays in the surrounding magnetic field; i.e., that PSR 1055 is embedded in a mini-Crab nebula. Observational tests of this hypothesis are suggested, and the implications of this result for pulsar evolution are briefly discussed.« less

Launch of the I13-2 data beamline at the Diamond Light Source synchrotron

NASA Astrophysics Data System (ADS)

Bodey, A. J.; Rau, C.

2017-06-01

Users of the Diamond-Manchester Imaging Branchline I13-2 commonly spend many months analysing the large volumes of tomographic data generated in a single beamtime. This is due to the difficulties inherent in performing complicated, computationally-expensive analyses on large datasets with workstations of limited computing power. To improve productivity, a ‘data beamline’ was launched in January 2016. Users are scheduled for visits to the data beamline in the same way as for regular beamlines, with bookings made via the User Administration System and provision of financial support for travel and subsistence. Two high-performance graphics workstations were acquired, with sufficient RAM to enable simultaneous analysis of several tomographic volumes. Users are given high priority on Diamond’s central computing cluster for the duration of their visit, and if necessary, archived data are restored to a high-performance disk array. Within the first six months of operation, thirteen user visits were made, lasting an average of 4.5 days each. The I13-2 data beamline was the first to be launched at Diamond Light Source and, to the authors’ knowledge, the first to be formalised in this way at any synchrotron.

Observation of Multi-bunch Interference with Coherent Synchrotron Radiation

NASA Astrophysics Data System (ADS)

Billinghurst, B. E.; May, T.; Bergstrom, J.; DeJong, M.; Dallin, L.

2010-02-01

The observation of Multi-bunch interference with coherent synchrotron radiation at the Canadian Light Source is discussed along with the possibility that some of the spectral features are driven by the radiation impedance of the vacuum chamber.

Local reconstruction in computed tomography of diffraction enhanced imaging

NASA Astrophysics Data System (ADS)

Huang, Zhi-Feng; Zhang, Li; Kang, Ke-Jun; Chen, Zhi-Qiang; Zhu, Pei-Ping; Yuan, Qing-Xi; Huang, Wan-Xia

2007-07-01

Computed tomography of diffraction enhanced imaging (DEI-CT) based on synchrotron radiation source has extremely high sensitivity of weakly absorbing low-Z samples in medical and biological fields. The authors propose a modified backprojection filtration(BPF)-type algorithm based on PI-line segments to reconstruct region of interest from truncated refraction-angle projection data in DEI-CT. The distribution of refractive index decrement in the sample can be directly estimated from its reconstruction images, which has been proved by experiments at the Beijing Synchrotron Radiation Facility. The algorithm paves the way for local reconstruction of large-size samples by the use of DEI-CT with small field of view based on synchrotron radiation source.

SUNY beamline facilities at the National Synchrotron Light Source (Final Report)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coppens, Philip

2003-06-22

The DOE sponsored SUNY synchrotron project has involved close cooperation among faculty at several SUNY campuses. A large number of students and postdoctoral associates have participated in its operation which was centered at the X3 beamline of the National Synchrotron Light Source at Brookhaven National Laboratory. Four stations with capabilities for Small Angle Scattering, Single Crystal and Powder and Surface diffraction and EXAFS were designed and operated with capability to perform experiments at very low as well as elevated temperatures and under high vacuum. A large amount of cutting-edge science was performed at the facility, which in addition provided excellentmore » training for students and postdoctoral scientists in the field.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Filhol, J. M.; Couprie, M. E.; Level, M. P.

SOLEIL is a third generation Synchrotron radiation Source, under construction in France at St Aubin, near Paris. The Storage Ring consists in a 357 m circumference ring, with 16 cells and 24 straight sections (4x12m, 12x7m, 8x3.6m), out of which up to 21 will house insertion devices. The optics, with distributed dispersion, features a low 3.7 nm.rad emittance at the 2.75 GeV operating energy, so as to provide high brilliance, from the VUV up to the hard X ray domain. In order to provide a long lifetime, and beam position stabilities in the micron range, significant attention was paid atmore » each design stage (optics, magnets, beam position monitors, vacuum and RF systems,..), including the design of the building and infrastructure, the construction of which is now complete. This resulted in some unprecedented approaches such as the intensive use of NEG coating Aluminium vessels, or the development of a dedicated superconducting RF cavity and of 190 kW solid state RF amplifiers. The construction, started in 2002, is now completed. The injector system (100 MeV Linac) and the 3 Hz full energy Booster synchrotron have reached nominal operating conditions by fall 2005. The installation of the Storage Ring was just completed and its commissioning started in May 2006. First 9 turns in the ring were achieved on May the 14th, and visible synchrotron radiation was also observed on a CCD camera. Innovative insertion devices were designed and built so as to provide the best possible performances in an energy range as large as 5 eV to 20 keV. These are helical electromagnetic devices with 640 mm and 256 mm periods, APPLE II type undulators with 80 mm period, and in-vacuum hybrid undulators with 20 mm period. Two infra-red beamlines providing both edge and constant dipole field emission are also under construction and a superconducting wiggler is currently being designed in order to provide high flux in the 10 to 50 keV range. A first set of 10 beamlines (out of 24 included in the project) is being built and will be tested from summer 2006 onwards, with the aim of starting Users operation by the beginning of 2007.« less

Status of the Commissioning of SOLEIL

NASA Astrophysics Data System (ADS)

Filhol, J. M.; Couprie, M. E.; Level, M. P.; Besson, J. C.; Brunelle, P.; Denard, J. C.; Godefroy, J. M.; Herbeaux, C.; Lebasque, P.; Le Roux, V.; Lestrade, A.; Loulergue, A.; Marchand, P.; Nadji, A.; Nadolski, L.; Nagaoka, R.; Pottin, B.; Tordeux, M. A.

2007-01-01

SOLEIL is a third generation Synchrotron radiation Source, under construction in France at St Aubin, near Paris. The Storage Ring consists in a 357 m circumference ring, with 16 cells and 24 straight sections (4×12m, 12×7m, 8×3.6m), out of which up to 21 will house insertion devices. The optics, with distributed dispersion, features a low 3.7 nm.rad emittance at the 2.75 GeV operating energy, so as to provide high brilliance, from the VUV up to the hard X ray domain. In order to provide a long lifetime, and beam position stabilities in the micron range, significant attention was paid at each design stage (optics, magnets, beam position monitors, vacuum and RF systems,..), including the design of the building and infrastructure, the construction of which is now complete. This resulted in some unprecedented approaches such as the intensive use of NEG coating Aluminium vessels, or the development of a dedicated superconducting RF cavity and of 190 kW solid state RF amplifiers. The construction, started in 2002, is now completed. The injector system (100 MeV Linac) and the 3 Hz full energy Booster synchrotron have reached nominal operating conditions by fall 2005. The installation of the Storage Ring was just completed and its commissioning started in May 2006. First 9 turns in the ring were achieved on May the 14th, and visible synchrotron radiation was also observed on a CCD camera. Innovative insertion devices were designed and built so as to provide the best possible performances in an energy range as large as 5 eV to 20 keV. These are helical electromagnetic devices with 640 mm and 256 mm periods, APPLE II type undulators with 80 mm period, and in-vacuum hybrid undulators with 20 mm period. Two infra-red beamlines providing both edge and constant dipole field emission are also under construction and a superconducting wiggler is currently being designed in order to provide high flux in the 10 to 50 keV range. A first set of 10 beamlines (out of 24 included in the project) is being built and will be tested from summer 2006 onwards, with the aim of starting Users operation by the beginning of 2007.

The third catalog of active galactic nuclei detected by the Fermi large area telescope

DOE PAGES

Ackermann, M.; Ajello, M.; Atwood, W. B.; ...

2015-08-25

We present the third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC). It is based on the third Fermi-LAT catalog (3FGL) of sources detected between 100 MeV and 300 GeV with a Test Statistic greater than 25, between 2008 August 4 and 2012 July 31. The 3LAC includes 1591 AGNs located at high Galactic latitudes (more » $$| b| \\gt 10^\\circ $$), a 71% increase over the second catalog based on 2 years of data. There are 28 duplicate associations, thus 1563 of the 2192 high-latitude gamma-ray sources of the 3FGL catalog are AGNs. Most of them (98%) are blazars. About half of the newly detected blazars are of unknown type, i.e., they lack spectroscopic information of sufficient quality to determine the strength of their emission lines. Based on their gamma-ray spectral properties, these sources are evenly split between flat-spectrum radio quasars (FSRQs) and BL Lacs. The most abundant detected BL Lacs are of the high-synchrotron-peaked (HSP) type. There were about 50% of the BL Lacs that had no measured redshifts. A few new rare outliers (HSP-FSRQs and high-luminosity HSP BL Lacs) are reported. The general properties of the 3LAC sample confirm previous findings from earlier catalogs. The fraction of 3LAC blazars in the total population of blazars listed in BZCAT remains non-negligible even at the faint ends of the BZCAT-blazar radio, optical, and X-ray flux distributions, which hints that even the faintest known blazars could eventually shine in gamma-rays at LAT-detection levels. Furthermore, the energy-flux distributions of the different blazar populations are in good agreement with extrapolation from earlier catalogs.« less

Recent Beam Measurements and New Instrumentation at the Advanced Light Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sannibale, F.; Baptiste, K.; Barry, W.

2012-04-11

The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and usedmore » in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.« less

RECENT BEAM MEASUREMENTS AND NEW INSTRUMENTATION AT THE ADVANCED LIGHT SOURCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sannibale, Fernando; Baptiste, Kenneth; Barry, Walter

2008-05-05

The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and usedmore » in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.« less

Applications of Coherent Radiation from Electrons traversing Crystals

NASA Astrophysics Data System (ADS)

Überall, H.

2000-04-01

Historically, the first types of coherent radiation from electrons traversing crystals studied were coherent bremsstrahlung (CB: Dyson and Überall 1955; Überall 1956, 1962) and channeling radiation (CR: Kumakhov, 1976) which produce quasimonochromatic X-rays and γ-rays, as well as parametric X-rays (Baryshevsky and Feranchuk, 1983). Related non-crystal sources are transition radiation and synchrotron radiation. We here present a comparison of radiation types from these sources, and we discuss a series of their possible applications, namely (a) CR: X-ray lithography, angiography, structure analysis of macromolecules, and trace element analysis, and (b) for CB: Radiography, use as a neutron source, elemental analysis, radiation therapy, and radioisotope production for commercial or medical use. CR and CB are very intense sources, needing only low-energy, moderately-priced electron linacs for their generation, hence competing with (or surpassing) more conventional X-ray sources intensity-wise and from a cost standpoint.

Kiloparsec Jet Properties of Hybrid, Low-, and High-Synchrotron-Peaked Blazars

NASA Astrophysics Data System (ADS)

Stanley, Ethan C.

Blazars are a rare class of active galactic nucleus (AGN) with relativistic jets closely aligned with the line of sight. Many aspects of the environments and kiloparsec-scale jet structure are not fully understood. Hybrid and high synchrotron peaked (HSP) blazars are two types of blazar that provide unique opportunities to study these jets. Hybrid blazars appear to have jets of differing morphology on each side of their core, suggesting that external factors shape their jet morphology. Three hybrid sources were investigated in radio, optical, and X-ray wavelengths: 8C 1849+670, PKS 2216-038, and PKS 1045-188. For all three, X-ray emission was detected only from the approaching jet. All three had jet radio flux densities and emission mechanisms similar to higher-power FR II sources, but two had approaching jets similar to lower-power FR I sources. None of the three showed definitive signs of asymmetry in their external environments. These results agree with previous multiwavelength studies of hybrid sources that show a dominance of FR I approaching jets and FR II emission mechanisms. With the addition of these three hybrid sources, 13 have been studied in total. Eleven have FR I approaching jets, and eight of those have FR II emission mechanisms. These trends may be due to small number statistics, or they may indicate other factors are creating hybrid-like appearances. High synchrotron peaked blazars are defined by the frequency of the peak of their jet synchrotron emission. Some have shown extreme variability which would imply incredibly-powerful and well-aligned jets, but VLBA observations have measured only modest jet speeds. A radio survey was performed to measure the extended radio luminosity of a large sample of HSP sources. These sources were compared to the complete radio flux density limited MOJAVE 1.5 Jy sample. Flat spectrum radio quasars (FSRQs) showed significant overlap with low synchrotron peaked (LSP) BL Lacs in multiple parameters, which may suggest that many FSRQs are "masquerading'' as LSP BL Lacs. HSP BL Lacs showed slightly lower extended radio luminosities and significantly lower maximum apparent jet speeds, suggesting that they are intrinsically weaker sources. There was a good correlation between maximum apparent jet speed and extended radio luminosity, which supports using the extended radio luminosity as a measure of intrinsic jet power. There was a lack of TeV-detected sources with higher extended radio luminosities, which suggests TeV emission may favor low power jets or high synchrotron peak frequencies. The apparent low power of HSP sources and TeV-detected sources questions any model of TeV emission and variability that depends on the jet (or a part of it) being intrinsically powerful.

Space charge effects on the third order coupled resonance

NASA Astrophysics Data System (ADS)

Franchetti, Giuliano; Gilardoni, Simone; Huschauer, Alexander; Schmidt, Frank; Wasef, Raymond

2017-08-01

The effect of space charge on bunched beams has been the subject of numerous numerical and experimental studies in the first decade of 2000. Experimental campaigns performed at the CERN Proton Synchrotron in 2002 and at the GSI SIS18 in 2008 confirmed the existence of an underlying mechanism in the beam dynamics of periodic resonance crossing induced by the synchrotron motion and space charge. In this article we present an extension of the previous studies to describe the effect of space charge on a controlled coupled (2D) third order resonance. The experimental and simulation results of this latest campaign shed a new light on the difficulties of the 2D particle dynamics. We find striking experimental evidence that space charge and the coupled resonance create an unusual coupling in the phase space, leading to the formation of an asymmetric halo. Moreover, this study demonstrates a clear link between halo formation and fixed-lines.

Microfocusing options for the inelastic X-ray scattering beamline at sector 3 of the Advanced Photon Source.

PubMed

Alsmadi, A M; Alatas, A; Zhao, J Y; Hu, M Y; Yan, L; Alp, E E

2014-05-01

Synchrotron radiation from third-generation high-brilliance storage rings is an ideal source for X-ray microbeams. The aim of this paper is to describe a microfocusing scheme that combines both a toroidal mirror and Kirkpatrick-Baez (KB) mirrors for upgrading the existing optical system for inelastic X-ray scattering experiments at sector 3 of the Advanced Photon Source. SHADOW ray-tracing simulations without considering slope errors of both the toroidal mirror and KB mirrors show that this combination can provide a beam size of 4.5 µm (H) × 0.6 µm (V) (FWHM) at the end of the existing D-station (66 m from the source) with use of full beam transmission of up to 59%, and a beam size of 3.7 µm (H) × 0.46 µm (V) (FWHM) at the front-end of the proposed E-station (68 m from the source) with a transmission of up to 52%. A beam size of about 5 µm (H) × 1 µm (V) can be obtained, which is close to the ideal case, by using high-quality mirrors (with slope errors of less than 0.5 µrad r.m.s.). Considering the slope errors of the existing toroidal and KB mirrors (5 and 2.9 µrad r.m.s., respectively), the beam size grows to about 13.5 µm (H) × 6.3 µm (V) at the end of the D-station and to 12.0 µm (H) × 6.0 µm (V) at the front-end of the proposed E-station. The simulations presented here are compared with the experimental measurements that are significantly larger than the theoretical values even when slope error is included in the simulations. This is because of the experimental set-up that could not yet be optimized.

Characterization of semiconductor materials using synchrotron radiation-based near-field infrared microscopy and nano-FTIR spectroscopy.

PubMed

Hermann, Peter; Hoehl, Arne; Ulrich, Georg; Fleischmann, Claudia; Hermelink, Antje; Kästner, Bernd; Patoka, Piotr; Hornemann, Andrea; Beckhoff, Burkhard; Rühl, Eckart; Ulm, Gerhard

2014-07-28

We describe the application of scattering-type near-field optical microscopy to characterize various semiconducting materials using the electron storage ring Metrology Light Source (MLS) as a broadband synchrotron radiation source. For verifying high-resolution imaging and nano-FTIR spectroscopy we performed scans across nanoscale Si-based surface structures. The obtained results demonstrate that a spatial resolution below 40 nm can be achieved, despite the use of a radiation source with an extremely broad emission spectrum. This approach allows not only for the collection of optical information but also enables the acquisition of near-field spectral data in the mid-infrared range. The high sensitivity for spectroscopic material discrimination using synchrotron radiation is presented by recording near-field spectra from thin films composed of different materials used in semiconductor technology, such as SiO2, SiC, SixNy, and TiO2.

1993 CAT workshop on beamline optical designs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1993-11-01

An Advanced Photon Source (APS) Collaborative Access Team (CAT) Workshop on Beamline Optical Designs was held at Argonne National Laboratory on July 26--27, 1993. The goal of this workshop was to bring together experts from various synchrotron sources to provide status reports on crystal, reflecting, and polarizing optics as a baseline for discussions of issues facing optical designers for CAT beamlines at the APS. Speakers from the European Synchrotron Radiation Facility (ESRF), the University of Chicago, the National Synchrotron Light Source, and the University of Manchester (England) described single- and double-crystal monochromators, mirrors, glass capillaries, and polarizing optics. Following thesemore » presentations, the 90 participants divided into three working groups: Crystal Optics Design, Reflecting Optics, and Optics for Polarization Studies. This volume contains copies of the presentation materials from all speakers, summaries of the three working groups, and a ``catalog`` of various monochromator designs.« less

Medical Applications of Synchrotron Radiation

DOE R&D Accomplishments Database

Thomlinson, W.

1991-10-01

Ever since the first diagnostic x-ray was done in the United States on February 3, 1896, the application of ionizing radiation to the field of medicine has become increasingly important. Both in clinical medicine and basic research the use of x-rays for diagnostic imaging and radiotherapy is now widespread. Radiography, angiography, CAT and PETT scanning, mammography, and nuclear medicine are all examples of technologies developed to image the human anatomy. In therapeutic applications, both external and internal sources of radiation are applied to the battle against cancer. The development of dedicated synchrotron radiation sources has allowed exciting advances to take place in many of these applications. The new sources provide tunable, high-intensity monochromatic beams over a wide range of energies which can be tailored to specific programmatic needs. This paper surveys those areas of medical research in which synchrotron radiation facilities are actively involved.

First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission

NASA Astrophysics Data System (ADS)

Bennett, C. L.; Hill, R. S.; Hinshaw, G.; Nolta, M. R.; Odegard, N.; Page, L.; Spergel, D. N.; Weiland, J. L.; Wright, E. L.; Halpern, M.; Jarosik, N.; Kogut, A.; Limon, M.; Meyer, S. S.; Tucker, G. S.; Wollack, E.

2003-09-01

The WMAP mission has mapped the full sky to determine the geometry, content, and evolution of the universe. Full-sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the cosmic microwave background (CMB) from foreground emission, including diffuse Galactic emission and Galactic and extragalactic point sources. We define masks that excise regions of high foreground emission, so CMB analyses can be carried out with minimal foreground contamination. We also present maps and spectra of the individual emission components, leading to an improved understanding of Galactic astrophysical processes. The effectiveness of template fits to remove foreground emission from the WMAP data is also examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We use a maximum entropy method to construct a model of the Galactic emission components. The observed total Galactic emission matches the model to less than 1%, and the individual model components are accurate to a few percent. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (βs~-2.5) near star-forming regions, especially in the plane, and steepest (βs~-3) in the halo. This is consistent with a picture of relativistic cosmic-ray electron generation in star-forming regions and diffusion and convection within the plane. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to βs<-3. The modeled thermal dust spectral index is also steep in the WMAP bands, with βd~2.2. Our model is driven to these conclusions by the low level of total foreground contamination at ~60 GHz. Microwave and Hα measurements of the ionized gas agree well with one another at about the expected levels. Spinning dust emission is limited to <~5% of the Ka-band foreground emission, assuming a thermal dust distribution with a cold neutral medium spectrum and a monotonically decreasing synchrotron spectrum. A catalog of 208 point sources is presented. The reliability of the catalog is 98%; i.e., we expect five of the 208 sources to be statistically spurious. The mean spectral index of the point sources is α~0 (β~-2). Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0+/-1.4)×10-3 μK2 sr at Q band and negligible levels at V band and W band. The Sunyaev-Zeldovich effect is shown to be a negligible ``contamination'' to the maps. WMAP is the result of a partnership between Princeton University and the NASA Goddard Space Flight Center. Scientific guidance is provided by the WMAP Science Team.

Single-crystal diffraction at megabar conditions by synchrotron radiation

NASA Astrophysics Data System (ADS)

Merlini, Marco; Hanfland, Michael

2013-08-01

Crystal structure determination at extreme pressures is currently possible at synchrotron beamlines optimized for such a purpose. We report the description of the experimental setup available at European Synchrotron Radiation Facility ID09 beamline (Grenoble, France) and, with two examples, we illustrate the state-of-the-art experiments currently performed at third-generation synchrotrons. The first example concerns the determination of the equation of state and the structural behavior of low-spin Fe-bearing siderite in the megabar pressure range. Siderite, in fact, undergoes a first-order isosymmetric transition at 45 GPa, and, above this pressure, it features Fe2+ in electronic low-spin configuration. The local configuration of Fe coordination polyhedra, determined by structural refinements, significantly deviates from a regular octahedron. Nevertheless, no further structural transition is detected up to the maximum pressure reached in our experiments, 135 GPa. The analysis of the Fe-O bond length extrapolated to ambient pressure, which indicates that the difference in ionic radii between the high- and the low-spin state of Fe2+ is 0.172 Å, in excellent agreement with the tabulated data by Shannon and Prewitt [Effective ionic radii in oxides and fluorides. Acta Crystallogr. 1969;B25:925-946]. The second example concerns the determination and refinement of the oP8 structure adopted by sodium in the pressure interval 118-125 GPa, using an experimental dataset collected at 118 GPa. The orthorhombic [a=4.7687(15) Å, b=3.0150(6) Å, c=5.2423(7) Å, V=75.4(3) Å3] oP8 structure is topologically related to the MnP structure, with two non-equivalent atoms in the unit cell. Despite the weak scattering factor of Na atoms, the quality of the data also allows meaningful displacement parameters refinements (R1=4.6%, 14 parameters, 190 diffractions, and 105 unique) demonstrating that the current accuracy of diffraction data at extreme pressures can be comparable with ambient condition measurements.

Analysis of rapidly synthesized guest-filled porous complexes with synchrotron radiation: Practical guidelines for the crystalline sponge method

DOE PAGES

Ramadhar, Timothy R.; Zheng, Shao -Liang; Chen, Yu -Sheng; ...

2015-01-01

A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collectionmore » times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flack x absolute stereochemical determination parameter to date for these systems. The structures did not require the use of PLATON/SQUEEZE or other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine occupancies, discussion of the proper use of geometric and anisotropic displacement parameter restraints and constraints, and whether to perform solvent squeezing/masking. The single-crystal-to-single-crystal transformation process for the crystal sponges is also discussed. The presented general guidelines will be invaluable for researchers interested in using the crystalline sponge method at in-house diffraction or synchrotron facilities, will facilitate the collection and analysis of reliable high-quality data, and will allow construction of chemically and physically sensible models for guest structural determination.« less

Outline of a Twenty-Five Year Plan for Development and Deployment of A Catapult for A Third Generation Space Shuttle

NASA Technical Reports Server (NTRS)

Russell, John M.

2002-01-01

This report reviews the rationale for catapult assist in the launching a third generation space shuttle. It then furnishes lists of early design decisions, questions whose answers are prerequisite to later design decisions, preliminary inventories of carriage levitation and carriage propulsion concepts, phases of the project and major milestones, and some sources of expertise to support the project.

Outline Of A Twenty-Five Year Plan For Development And Deployment Of a Catapult For a Third Generation Space Shuttle

NASA Technical Reports Server (NTRS)

Russell, John M.

2001-01-01

This report reviews the rationale for catapult assist in the launching of a third generation space shuttle. It then furnishes lists of early design decisions, questions whose answers are prerequisite to later design decisions, preliminary inventories of carriage levitation and carriage propulsion concepts, phases of the project and major milestones, and some sources of expertise to support the project.

Exploring synchrotron radiation capabilities: The ALS-Intel CRADA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gozzo, F.; Cossy-Favre, A; Trippleet, B.

1997-04-01

Synchrotron radiation spectroscopy and spectromicroscopy were applied, at the Advanced Light Source, to the analysis of materials and problems of interest to the commercial semiconductor industry. The authors discuss some of the results obtained at the ALS using existing capabilities, in particular the small spot ultra-ESCA instrument on beamline 7.0 and the AMS (Applied Material Science) endstation on beamline 9.3.2. The continuing trend towards smaller feature size and increased performance for semiconductor components has driven the semiconductor industry to invest in the development of sophisticated and complex instrumentation for the characterization of microstructures. Among the crucial milestones established by themore » Semiconductor Industry Association are the needs for high quality, defect free and extremely clean silicon wafers, very thin gate oxides, lithographies near 0.1 micron and advanced material interconnect structures. The requirements of future generations cannot be met with current industrial technologies. The purpose of the ALS-Intel CRADA (Cooperative Research And Development Agreement) is to explore, compare and improve the utility of synchrotron-based techniques for practical analysis of substrates of interest to semiconductor chip manufacturing. The first phase of the CRADA project consisted in exploring existing ALS capabilities and techniques on some problems of interest. Some of the preliminary results obtained on Intel samples are discussed here.« less

The synchrotron-self-Compton process in spherical geometries. I - Theoretical framework

NASA Technical Reports Server (NTRS)

Band, D. L.; Grindlay, J. E.

1985-01-01

Both spatial and spectral accuracies are stressed in the present method for the calculation of the synchrotron-self-Compton model in spherical geometries, especially in the partially opaque regime of the synchrotron spectrum of inhomogeneous sources that can span a few frequency decades and contribute a significant portion of the scattered flux. A formalism is developed that permits accurate calculation of incident photon density throughout an optically thin sphere. An approximation to the Klein-Nishina cross section is used to model the effects of variable electron and incident photon cutoffs, as well as the decrease in the cross section at high energies. General results are derived for the case of inhomogeneous sources with power law profiles in both electron density and magnetic field.

Excited states of aniline by photoabsorption spectroscopy in the 30,000-90,000 cm(-1) region using synchrotron radiation.

PubMed

Rajasekhar, B N; Veeraiah, A; Sunanda, K; Jagatap, B N

2013-08-14

The photoabsorption spectrum of aniline (C6H5NH2) in gas phase in the 30,000-90,000 cm(-1) (3.7-11.2 eV) region is recorded at resolution limit of 0.008 eV using synchrotron radiation source for the first time to comprehend the nature of the excited valence and Rydberg states. The first half of the energy interval constitutes the richly structured valence transitions from the ground to excited states up to the first ionization potential (IP) at 8.02 eV. The spectrum in the second half consists of vibrational features up to second IP (9.12 eV) and structureless broad continuum up to the third IP (10.78 eV). The electronic states are assigned mainly to the singlets belonging to π → π* transitions. A few weak initial members of Rydberg states arising from π → 4s, np or nd transitions are also identified. Observed vibrational features are assigned to transitions from the ground state A' to the excited states 1A", 3A', 5A", 6A', and 10A" in C(s) symmetry. Time dependent density functional theory (TDDFT) calculations at B3LYP level of theory are employed to obtain the vertical excitation energies and the symmetries of the excited states in equilibrium configuration. The computed values of the transition energies agree fairly well with the experimental data. Further the calculated oscillator strengths are used to substantiate the assignments of the bands. The work provides a comprehensive picture of the vacuum ultraviolet photoabsorption spectrum of aniline up to its third ionization limit.

Radiological considerations for bulk shielding calculations of national synchrotron light source-II

NASA Astrophysics Data System (ADS)

Job, Panakkal K.; Casey, William R.

2011-12-01

Brookhaven National Laboratory is designing a new electron synchrotron for scientific research using synchrotron radiation. This facility, called the “National Synchrotron Light Source II” (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors and robotics, and a suite of scientific instruments designed to maximize the scientific output of the facility. The project scope includes the design, construction, installation, and commissioning of the following accelerators: a 200 MeV linac, a booster synchrotron operating from 200 MeV to 3.0 GeV, and the storage ring which stores a maximum of 500 mA current of electrons at an energy of 3.0 GeV. It is planned to operate the facility primarily in a top-off mode, thereby maintaining the maximum variation in stored beam current to <1%. Because of the very demanding requirements for beam emittance and synchrotron radiation brilliance, the beam life-time is expected to be quite low, on the order of 2 h. Analysis of the bulk shielding for operating this facility and the input parameters used for this analysis have been discussed in this paper. The characteristics of each of the accelerators and their operating modes have been summarized with the input assumptions for the bulk shielding analysis.

Analytical methods development for supramolecular design in solar hydrogen production

NASA Astrophysics Data System (ADS)

Brown, J. R.; Elvington, M.; Mongelli, M. T.; Zigler, D. F.; Brewer, K. J.

2006-08-01

In the investigation of alternative energy sources, specifically, solar hydrogen production from water, the ability to perform experiments with a consistent and reproducible light source is key to meaningful photochemistry. The design, construction, and evaluation of a series of LED array photolysis systems for high throughput photochemistry have been performed. Three array systems of increasing sophistication are evaluated using calorimetric measurements and potassium tris(oxalato)ferrate(II) chemical actinometry and compared with a traditional 1000 W Xe arc lamp source. The results are analyzed using descriptive statistics and analysis of variance (ANOVA). The third generation array is modular, and controllable in design. Furthermore, the third generation array system is shown to be comparable in both precision and photonic output to a 1000 W Xe arc lamp.

Label-free imaging of atherosclerotic plaques using third-harmonic generation microscopy

PubMed Central

Small, David M.; Jones, Jason S.; Tendler, Irwin I.; Miller, Paul E.; Ghetti, Andre; Nishimura, Nozomi

2017-01-01

Multiphoton microscopy using laser sources in the mid-infrared range (MIR, 1,300 nm and 1,700 nm) was used to image atherosclerotic plaques from murine and human samples. Third harmonic generation (THG) from atherosclerotic plaques revealed morphological details of cellular and extracellular lipid deposits. Simultaneous nonlinear optical signals from the same laser source, including second harmonic generation and endogenous fluorescence, resulted in label-free images of various layers within the diseased vessel wall. The THG signal adds an endogenous contrast mechanism with a practical degree of specificity for atherosclerotic plaques that complements current nonlinear optical methods for the investigation of cardiovascular disease. Our use of whole-mount tissue and backward scattered epi-detection suggests THG could potentially be used in the future as a clinical tool. PMID:29359098

Blazar flaring patterns (B-FlaP) classifying blazar candidate of uncertain type in the third Fermi-LAT catalogue by artificial neural networks

NASA Astrophysics Data System (ADS)

Chiaro, G.; Salvetti, D.; La Mura, G.; Giroletti, M.; Thompson, D. J.; Bastieri, D.

2016-11-01

The Fermi-Large Area Telescope (LAT) is currently the most important facility for investigating the GeV γ-ray sky. With Fermi-LAT, more than three thousand γ-ray sources have been discovered so far. 1144 (˜40 per cent) of the sources are active galaxies of the blazar class, and 573 (˜20 per cent) are listed as blazar candidate of uncertain type (BCU), or sources without a conclusive classification. We use the empirical cumulative distribution functions and the artificial neural networks for a fast method of screening and classification for BCUs based on data collected at γ-ray energies only, when rigorous multiwavelength analysis is not available. Based on our method, we classify 342 BCUs as BL Lacs and 154 as flat-spectrum radio quasars, while 77 objects remain uncertain. Moreover, radio analysis and direct observations in ground-based optical observatories are used as counterparts to the statistical classifications to validate the method. This approach is of interest because of the increasing number of unclassified sources in Fermi catalogues and because blazars and in particular their subclass high synchrotron peak objects are the main targets of atmospheric Cherenkov telescopes.

Single-source chest-abdomen-pelvis cancer staging on a third generation dual-source CT system: comparison of automated tube potential selection to second generation dual-source CT.

PubMed

Park, Clara; Gruber-Rouh, Tatjana; Leithner, Doris; Zierden, Amelie; Albrecht, Mortiz H; Wichmann, Julian L; Bodelle, Boris; Elsabaie, Mohamed; Scholtz, Jan-Erik; Kaup, Moritz; Vogl, Thomas J; Beeres, Martin

2016-10-10

Evaluation of latest generation automated attenuation-based tube potential selection (ATPS) impact on image quality and radiation dose in contrast-enhanced chest-abdomen-pelvis computed tomography examinations for gynaecologic cancer staging. This IRB approved single-centre, observer-blinded retrospective study with a waiver for informed consent included a total of 100 patients with contrast-enhanced chest-abdomen-pelvis CT for gynaecologic cancer staging. All patients were examined with activated ATPS for adaption of tube voltage to body habitus. 50 patients were scanned on a third-generation dual-source CT (DSCT), and another 50 patients on a second-generation DSCT. Predefined image quality setting remained stable between both groups at 120 kV and a current of 210 Reference mAs. Subjective image quality assessment was performed by two blinded readers independently. Attenuation and image noise were measured in several anatomic structures. Signal-to-noise ratio (SNR) was calculated. For the evaluation of radiation exposure, CT dose index (CTDI vol ) values were compared. Diagnostic image quality was obtained in all patients. The median CTDI vol (6.1 mGy, range 3.9-22 mGy) was 40 % lower when using the algorithm compared with the previous ATCM protocol (median 10.2 mGy · cm, range 5.8-22.8 mGy). A reduction in potential to 90 kV occurred in 19 cases, a reduction to 100 kV in 23 patients and a reduction to 110 kV in 3 patients of our experimental cohort. These patients received significantly lower radiation exposure compared to the former used protocol. Latest generation automated ATPS on third-generation DSCT provides good diagnostic image quality in chest-abdomen-pelvis CT while average radiation dose is reduced by 40 % compared to former ATPS protocol on second-generation DSCT.

Simulations of Coherent Synchrotron Radiation Effects in Electron Machines

NASA Astrophysics Data System (ADS)

Migliorati, M.; Schiavi, A.; Dattoli, G.

2007-09-01

Coherent synchrotron radiation (CSR) generated by high intensity electron beams can be a source of undesirable effects limiting the performance of storage rings. The complexity of the physical mechanisms underlying the interplay between the electron beam and the CSR demands for reliable simulation codes. In the past, codes based on Lie algebraic techniques have been very efficient to treat transport problems in accelerators. The extension of these methods to the non linear case is ideally suited to treat wakefields - beam interaction. In this paper we report on the development of a numerical code, based on the solution of the Vlasov equation, which includes the non linear contribution due to wakefields. The proposed solution method exploits an algebraic technique that uses the exponential operators. We show that, in the case of CSR wakefields, the integration procedure is capable of reproducing the onset of an instability which leads to microbunching of the beam thus increasing the CSR at short wavelengths. In addition, considerations on the threshold of the instability for Gaussian bunches is also reported.

Simulations of Coherent Synchrotron Radiation Effects in Electron Machines

NASA Astrophysics Data System (ADS)

Migliorati, M.; Schiavi, A.; Dattoli, G.

Coherent synchrotron radiation (CSR) generated by high intensity electron beams can be a source of undesirable effects limiting the performance of storage rings. The complexity of the physical mechanisms underlying the interplay between the electron beam and the CSR demands for reliable simulation codes. In the past, codes based on Lie algebraic techniques have been very efficient to treat transport problems in accelerators. The extension of these methods to the non linear case is ideally suited to treat wakefields - beam interaction. In this paper we report on the development of a numerical code, based on the solution of the Vlasov equation, which includes the non linear contribution due to wakefields. The proposed solution method exploits an algebraic technique that uses the exponential operators. We show that, in the case of CSR wakefields, the integration procedure is capable of reproducing the onset of an instability which leads to microbunching of the beam thus increasing the CSR at short wavelengths. In addition, considerations on the threshold of the instability for Gaussian bunches is also reported.

FIR Synchrotron Spectroscopy of High Torsional Levels of CD_3OH: the Tau of Methanol

NASA Astrophysics Data System (ADS)

Lees, Ronald M.; Xu, Li-Hong; Billinghurst, Brant E.

2015-06-01

Sub-bands involving high torsional levels of the CD_3OH isotopologue of methanol have been analyzed in Fourier transform spectra recorded at the Far-Infrared beamline of the Canadian Light Source synchrotron in Saskatoon. Energy term values for A and E torsional species of the third excited torsional state, v_t = 3, are now almost complete up to rotational levels K = 15, and thirteen substates have so far been identified for v_t = 4. The spectra show interesting close groupings of high-v_t sub-bands related by Dennison's torsional symmetry label τ, rather than A and E, that can be understood in terms of a simple and universal free-rotor "spectral predictor" chart. Transitions between states on the same free rotor curve have torsional overlap matrix elements close to unity, so give rise to strong sub-bands providing radiative routes for rapid population transfer through the high torsional manifold. Where the energy curves for the v_t = 3 and 4 ground-state torsional levels pass through the excited vibrational states, strong resonances can occur and a number of anharmonic and Coriolis interactions have been detected through perturbations to the spectra and appearance of forbidden transitions due to strong mixing and intensity borrowing.

Method and System for Temporal Filtering in Video Compression Systems

NASA Technical Reports Server (NTRS)

Lu, Ligang; He, Drake; Jagmohan, Ashish; Sheinin, Vadim

2011-01-01

Three related innovations combine improved non-linear motion estimation, video coding, and video compression. The first system comprises a method in which side information is generated using an adaptive, non-linear motion model. This method enables extrapolating and interpolating a visual signal, including determining the first motion vector between the first pixel position in a first image to a second pixel position in a second image; determining a second motion vector between the second pixel position in the second image and a third pixel position in a third image; determining a third motion vector between the first pixel position in the first image and the second pixel position in the second image, the second pixel position in the second image, and the third pixel position in the third image using a non-linear model; and determining a position of the fourth pixel in a fourth image based upon the third motion vector. For the video compression element, the video encoder has low computational complexity and high compression efficiency. The disclosed system comprises a video encoder and a decoder. The encoder converts the source frame into a space-frequency representation, estimates the conditional statistics of at least one vector of space-frequency coefficients with similar frequencies, and is conditioned on previously encoded data. It estimates an encoding rate based on the conditional statistics and applies a Slepian-Wolf code with the computed encoding rate. The method for decoding includes generating a side-information vector of frequency coefficients based on previously decoded source data and encoder statistics and previous reconstructions of the source frequency vector. It also performs Slepian-Wolf decoding of a source frequency vector based on the generated side-information and the Slepian-Wolf code bits. The video coding element includes receiving a first reference frame having a first pixel value at a first pixel position, a second reference frame having a second pixel value at a second pixel position, and a third reference frame having a third pixel value at a third pixel position. It determines a first motion vector between the first pixel position and the second pixel position, a second motion vector between the second pixel position and the third pixel position, and a fourth pixel value for a fourth frame based upon a linear or nonlinear combination of the first pixel value, the second pixel value, and the third pixel value. A stationary filtering process determines the estimated pixel values. The parameters of the filter may be predetermined constants.

Elemental Composition of Mars Return Samples Using X-Ray Fluorescence Imaging at the National Synchrotron Light Source II

NASA Astrophysics Data System (ADS)

Thieme, J.; Hurowitz, J. A.; Schoonen, M. A.; Fogelqvist, E.; Gregerson, J.; Farley, K. A.; Sherman, S.; Hill, J.

2018-04-01

NSLS-II at BNL provides a unique and critical capability to perform assessments of the elemental composition and the chemical state of Mars returned samples using synchrotron radiation X-ray fluorescence imaging and X-ray absorption spectroscopy.

Plastique: A synchrotron radiation beamline for time resolved fluorescence in the frequency domain

NASA Astrophysics Data System (ADS)

De Stasio, Gelsomina; Zema, N.; Antonangeli, F.; Savoia, A.; Parasassi, T.; Rosato, N.

1991-06-01

PLASTIQUE is the only synchrotron radiation beamline in the world that performs time resolved fluorescence experiments in frequency domain. These experiments are extremely valuable sources of information on the structure and dynamics of molecules. We describe the beamline and some initial data.

Ion Conductivity and Sensors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bychkov, E.; Tveryanovich, Y.; Vlasov, Y.

2005-03-02

Ionic transport in glasses was discovered in the 19th century following the classical work of Warburg (1884). Since then, considerable progress has been achieved in both theoretical understanding and practical applications of ion-conducting vitreous systems (see Frischat, 1975; Malugani and Robert, 1980; Ribes, Barrau and Souquet, 1980; Kennedy and Yang, 1987; Vlasov and Bychkov, 1987; Hayashi, Tatsumisago and Minami, 1999; Doremus, 1962 and references therein). Nevertheless, this topic and especially the ion-conducting mechanisms in disordered solids need additional study using traditional macroscopic methods (ac and dc electrical conductivity, tracer diffusion, and ion transport number measurements), as well as advanced structuralmore » techniques on third generation synchrotron light sources and spallation neutron sources over a large range of the scattering vector Q. This approach led to the discovery of important features: in particular, different transport regimes at low and high mobile ion content that are closely related to a competition between the stochastic scenario and a non-random distribution of the mobile ions in the glass network. Well-known experimental findings such as compositional dependence of the Haven ratio H{sub R}, interpreted earlier by a number of drastically different ion transport models, can also be explained using a unified approach. Many of the new experimental results were obtained for silver and copper chalcogenide glasses which appear to be useful model materials, in part because of a large accessible composition domain, as well as coverage of five orders of magnitude in the mobile cation content, and corresponding dramatic changes in the ionic transport up to 10 orders of magnitude.« less

Development of at-wavelength metrology for x-ray optics at the ALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yashchuk, Valeriy V.; Goldberg, Kenneth A.; Yuan, Sheng

2010-07-09

The comprehensive realization of the exciting advantages of new third- and forth-generation synchrotron radiation light sources requires concomitant development of reflecting and diffractive x-ray optics capable of micro- and nano-focusing, brightness preservation, and super high resolution. The fabrication, tuning, and alignment of the optics are impossible without adequate metrology instrumentation, methods, and techniques. While the accuracy of ex situ optical metrology at the Advanced Light Source (ALS) has reached a state-of-the-art level, wavefront control on beamlines is often limited by environmental and systematic alignment factors, and inadequate in situ feedback. At ALS beamline 5.3.1, we are developing broadly applicable, high-accuracy,more » in situ, at-wavelength wavefront measurement techniques to surpass 100-nrad slope measurement accuracy for Kirkpatrick-Baez (KB) mirrors. The at-wavelength methodology we are developing relies on a series of tests with increasing accuracy and sensitivity. Geometric Hartmann tests, performed with a scanning illuminated sub-aperture determine the wavefront slope across the full mirror aperture. Shearing interferometry techniques use coherent illumination and provide higher sensitivity wavefront measurements. Combining these techniques with high precision optical metrology and experimental methods will enable us to provide in situ setting and alignment of bendable x-ray optics to realize diffraction-limited, sub 50 nm focusing at beamlines. We describe here details of the metrology beamline endstation, the x-ray beam diagnostic system, and original experimental techniques that have already allowed us to precisely set a bendable KB mirror to achieve a focused spot size of 150 nm.« less

Planck intermediate results. VII. Statistical properties of infrared and radio extragalactic sources from the Planck Early Release Compact Source Catalogue at frequencies between 100 and 857 GHz

NASA Astrophysics Data System (ADS)

Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Argüeso, F.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Balbi, A.; Banday, A. J.; Barreiro, R. B.; Battaner, E.; Benabed, K.; Benoît, A.; Bernard, J.-P.; Bersanelli, M.; Bethermin, M.; Bhatia, R.; Bonaldi, A.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Burigana, C.; Cabella, P.; Cardoso, J.-F.; Catalano, A.; Cayón, L.; Chamballu, A.; Chary, R.-R.; Chen, X.; Chiang, L.-Y.; Christensen, P. R.; Clements, D. L.; Colafrancesco, S.; Colombi, S.; Colombo, L. P. L.; Coulais, A.; Crill, B. P.; Cuttaia, F.; Danese, L.; Davis, R. J.; de Bernardis, P.; de Gasperis, G.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Dörl, U.; Douspis, M.; Dupac, X.; Efstathiou, G.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Fosalba, P.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Giard, M.; Giardino, G.; Giraud-Héraud, Y.; González-Nuevo, J.; Górski, K. M.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Harrison, D.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Jaffe, T. R.; Jaffe, A. H.; Jagemann, T.; Jones, W. C.; Juvela, M.; Keihänen, E.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurinsky, N.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lawrence, C. R.; Leonardi, R.; Lilje, P. B.; López-Caniego, M.; Macías-Pérez, J. F.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Mitra, S.; Miville-Deschènes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sajina, A.; Sandri, M.; Savini, G.; Scott, D.; Smoot, G. F.; Starck, J.-L.; Sudiwala, R.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Türler, M.; Valenziano, L.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; White, M.; Yvon, D.; Zacchei, A.; Zonca, A.

2013-02-01

We make use of the Planck all-sky survey to derive number counts and spectral indices of extragalactic sources - infrared and radio sources - from the Planck Early Release Compact Source Catalogue (ERCSC) at 100 to 857 GHz (3 mm to 350 μm). Three zones (deep, medium and shallow) of approximately homogeneous coverage are used to permit a clean and controlled correction for incompleteness, which was explicitly not done for the ERCSC, as it was aimed at providing lists of sources to be followed up. Our sample, prior to the 80% completeness cut, contains between 217 sources at 100 GHz and 1058 sources at 857 GHz over about 12 800 to 16 550 deg2 (31 to 40% of the sky). After the 80% completeness cut, between 122 and 452 and sources remain, with flux densities above 0.3 and 1.9 Jy at 100 and 857 GHz. The sample so defined can be used for statistical analysis. Using the multi-frequency coverage of the Planck High Frequency Instrument, all the sources have been classified as either dust-dominated (infrared galaxies) or synchrotron-dominated (radio galaxies) on the basis of their spectral energy distributions (SED). Our sample is thus complete, flux-limited and color-selected to differentiate between the two populations. We find an approximately equal number of synchrotron and dusty sources between 217 and 353 GHz; at 353 GHz or higher (or 217 GHz and lower) frequencies, the number is dominated by dusty (synchrotron) sources, as expected. For most of the sources, the spectral indices are also derived. We provide for the first time counts of bright sources from 353 to 857 GHz and the contributions from dusty and synchrotron sources at all HFI frequencies in the key spectral range where these spectra are crossing. The observed counts are in the Euclidean regime. The number counts are compared to previously published data (from earlier Planck results, Herschel, BLAST, SCUBA, LABOCA, SPT, and ACT) and models taking into account both radio or infrared galaxies, and covering a large range of flux densities. We derive the multi-frequency Euclidean level - the plateau in the normalised differential counts at high flux-density - and compare it to WMAP, Spitzer and IRAS results. The submillimetre number counts are not well reproduced by current evolution models of dusty galaxies, whereas the millimetre part appears reasonably well fitted by the most recent model for synchrotron-dominated sources. Finally we provide estimates of the local luminosity density of dusty galaxies, providing the first such measurements at 545 and 857 GHz. Appendices are available in electronic form at http://www.aanda.orgCorresponding author: herve.dole@ias.u-psud.fr

Detection of microvasculature alterations by synchrotron radiation in murine with delayed jellyfish envenomation syndrome.

PubMed

Wang, Beilei; Zhang, Bo; Huo, Hua; Wang, Tao; Wang, Qianqian; Wu, Yuanlin; Xiao, Liang; Ren, Yuqi; Zhang, Liming

2014-04-01

Using the tentacle extract (TE) from the jellyfish Cyanea capillata, we have previously established a delayed jellyfish envenomation syndrome (DJES) model, which is meaningful for clinical interventions against jellyfish stings. However, the mechanism of DJES still remains unclear. Thus, this study aimed to explore its potential mechanism by detecting TE-induced microvasculature alterations in vivo and ex vivo. Using a third-generation synchrotron radiation facility, we, for the first time, directly observed the blood vessel alterations induced by jellyfish venom in vivo and ex vivo. Firstly, microvasculature imaging of whole-body mouse in vivo indicated that the small blood vessel branches in the liver and kidney in the TE-treated group, seemed much thinner than those in the control group. Secondly, 3D imaging of kidney ex vivo showed that the kidneys in the TE-treated group had incomplete vascular trees where distal vessel branches were partly missing and disorderly disturbed. Finally, histopathological analysis found that obvious morphological changes, especially hemorrhagic effects, were also present in the TE-treated kidney. Thus, TE-induced microvasculature changes might be one of the important mechanisms of multiple organ dysfunctions in DJES. In addition, the methods we employed here will probably facilitate further studies on developing effective intervention strategies against DJES. Copyright © 2014 Elsevier Ltd. All rights reserved.

AI-BL1.0: a program for automatic on-line beamline optimization using the evolutionary algorithm.

PubMed

Xi, Shibo; Borgna, Lucas Santiago; Zheng, Lirong; Du, Yonghua; Hu, Tiandou

2017-01-01

In this report, AI-BL1.0, an open-source Labview-based program for automatic on-line beamline optimization, is presented. The optimization algorithms used in the program are Genetic Algorithm and Differential Evolution. Efficiency was improved by use of a strategy known as Observer Mode for Evolutionary Algorithm. The program was constructed and validated at the XAFCA beamline of the Singapore Synchrotron Light Source and 1W1B beamline of the Beijing Synchrotron Radiation Facility.

A NEW THERMIONIC RF ELECTRON GUN FOR SYNCHROTRON LIGHT SOURCES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kutsaev, Sergey; Agustsson, R.; Hartzell, J

A thermionic RF gun is a compact and efficient source of electrons used in many practical applications. RadiaBeam Systems and the Advanced Photon Source at Argonne National Laboratory collaborate in developing of a reliable and robust thermionic RF gun for synchrotron light sources which would offer substantial improvements over existing thermionic RF guns and allow stable operation with up to 1A of beam peak current at a 100 Hz pulse repetition rate and a 1.5 μs RF pulse length. In this paper, we discuss the electromagnetic and engineering design of the cavity and report the progress towards high power testsmore » of the cathode assembly of the new gun.« less

Investigation of fundamental limits to beam brightness available from photoinjectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bazarov, Ivan

2015-07-09

The goal of this project was investigation of fundamental limits to beam brightness available from photoinjectors. This basic research in accelerator physics spanned over 5 years aiming to extend the fundamental understanding of high average current, low emittance sources of relativistic electrons based on photoemission guns, a necessary prerequisite for a new generation of coherent X-ray synchrotron radiation facilities based on continuous duty superconducting linacs. The program focused on two areas critical to making advances in the electron source performance: 1) the physics of photocathodes for the production of low emittance electrons and 2) control of space charge forces inmore » the immediate vicinity to the cathode via 3D laser pulse shaping.« less

Current Status of the Beam Position Monitoring System at TLS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuo, C. H.; Hu, K. H.; Chen, Jenny

2006-11-20

The beam position monitoring system is an important part of a synchrotron light source that supports its routine operation and studies of beam physics. The Taiwan light source is equipped with 59 BPMs. Highly precise closed orbits are measured by multiplexing BPMs. Data are acquired using multi-channel 16-bit ADC modules. Orbit data are sampled every millisecond. Fast orbit data are shared in a reflective memory network to support fast orbit feedback. Averaged data were updated to control database at a rate of 10 Hz. A few new generation digital BPMs were tested to evaluate their performance and functionality. This reportmore » summarizes the system structure, the software environment and the preliminary beam test of the BPM system.« less

Quantitative Evaluation of Hard X-ray Damage to Biological Samples using EUV Ptychography

NASA Astrophysics Data System (ADS)

Baksh, Peter; Odstrcil, Michal; Parsons, Aaron; Bailey, Jo; Deinhardt, Katrin; Chad, John E.; Brocklesby, William S.; Frey, Jeremy G.

2017-06-01

Coherent diffractive imaging (CDI) has become a standard method on a variety of synchrotron beam lines. The high brilliance short wavelength radiation from these sources can be used to reconstruct attenuation and relative phase of a sample with nanometre resolution via CDI methods. However, the interaction between the sample and high energy ionising radiation can cause degradation to sample structure. We demonstrate, using a laboratory based high harmonic generation (HHG) based extreme ultraviolet (EUV) source, imaging a sample of hippocampal neurons using the ptychography method. The significant increase in contrast of the sample in the EUV light allows identification of damage induced from exposure to 7.3 keV photons, without causing any damage to the sample itself.

Current Status of the Beam Position Monitoring System at TLS

NASA Astrophysics Data System (ADS)

Kuo, C. H.; Hu, K. H.; Chen, Jenny; Lee, Demi; Wang, C. J.; Hsu, S. Y.; Hsu, K. T.

2006-11-01

The beam position monitoring system is an important part of a synchrotron light source that supports its routine operation and studies of beam physics. The Taiwan light source is equipped with 59 BPMs. Highly precise closed orbits are measured by multiplexing BPMs. Data are acquired using multi-channel 16-bit ADC modules. Orbit data are sampled every millisecond. Fast orbit data are shared in a reflective memory network to support fast orbit feedback. Averaged data were updated to control database at a rate of 10 Hz. A few new generation digital BPMs were tested to evaluate their performance and functionality. This report summarizes the system structure, the software environment and the preliminary beam test of the BPM system.

Transverse gradient in Apple-type undulators

PubMed Central

Calvi, M.; Camenzuli, C.; Prat, E.; Schmidt, Th.

2017-01-01

Apple-type undulators are globally recognized as the most flexible devices for the production of variable polarized light in the soft X-ray regime, both at synchrotron and free-electron laser facilities. Recently, the implementation of transverse gradient undulators has been proposed to enhance the performance of new generation light sources. In this paper it is demonstrated that Apple undulators do not only generate linear and elliptical polarized light but also variable transverse gradient under certain conditions. A general theoretical framework is introduced to evaluate the K-value and its transverse gradient for an Apple undulator, and formulas for all regular operational modes and different Apple types (including the most recent Delta type and Apple X) are calculated and critically discussed. PMID:28452751

Fabrication and testing of a newly designed slit system for depth-resolved X-ray diffraction measurements

DOE PAGES

Sinsheimer, John; Bouet, Nathalie; Ghose, Sanjit; ...

2016-10-06

A new system of slits called `spiderweb slits' have been developed for depth-resolved powder or polycrystalline X-ray diffraction measurements. The slits act on diffracted X-rays to select a particular gauge volume of sample, while absorbing diffracted X-rays from outside of this volume. Although the slit geometry is to some extent similar to that of previously developed conical slits or spiral slits, this new design has advantages over the previous ones in use for complex heterogeneous materials and in situ and operando diffraction measurements. For example, the slits can measure a majority of any diffraction cone for any polycrystalline material, overmore » a continuous range of diffraction angles, and work for X-ray energies of tens to hundreds of kiloelectronvolts. In addition, the design is generated and optimized using ray-tracing simulations, and fabricated through laser micromachining. The first prototype was successfully tested at the X17A beamline at the National Synchrotron Light Source, and shows similar performance to simulations, demonstrating gauge volume selection for standard powders, for all diffraction peaks over angles of 2–10°. A similar, but improved, design will be implemented at the X-ray Powder Diffraction beamline at the National Synchrotron Light Source II.« less

Beamlines of the Biomedical Imaging and Therapy Facility at the Canadian Light Source - Part 2

NASA Astrophysics Data System (ADS)

Wysokinski, T. W.; Chapman, D.; Adams, G.; Renier, M.; Suortti, P.; Thomlinson, W.

2013-03-01

The BioMedical Imaging and Therapy (BMIT) facility provides a world class facility with unique synchrotron-specific imaging and therapy capabilities. This paper describes Insertion Device (ID) beamline 05ID-2 with the beam terminated in the first experimental hutch: POE-2. The experimental methods available in POE-2 include: Microbeam Radiation Therapy (MRT), Synchrotron Stereotactic Radiation Therapy (SSRT) and absorption imaging (projection and Computed Tomography (CT)). The source for the ID beamline is a multi-pole superconductive 4.3 T wiggler, which can generate ~30 kW of radiative power and deliver dose as high as 3000 Gy/s required for MRT program. The optics in POE-1 hutch prepares either monochromatic or filtered white beam that is used in POE-2. The Double Crystal (DC), bent Laue monochromator will prepare a beam over 10 cm wide at sample point, while spanning an energy range appropriate for imaging studies of animals (20-100+ keV). The experimental hutch will have a flexible positioning system that can handle subjects up to 120 kg. Several different cameras will be available with resolutions ranging from 4 μm to 150 μm. The latest update on the status of 05B1-1 bending magnet (BM) beamline, described in Part 1 [1], is also included.

Fabrication and testing of a newly designed slit system for depth-resolved X-ray diffraction measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinsheimer, John; Bouet, Nathalie; Ghose, Sanjit

2016-10-06

A new system of slits called `spiderweb slits' have been developed for depth-resolved powder or polycrystalline X-ray diffraction measurements. The slits act on diffracted X-rays to select a particular gauge volume of sample, while absorbing diffracted X-rays from outside of this volume. Although the slit geometry is to some extent similar to that of previously developed conical slits or spiral slits, this new design has advantages over the previous ones in use for complex heterogeneous materials andin situandoperandodiffraction measurements. For example, the slits can measure a majority of any diffraction cone for any polycrystalline material, over a continuous range ofmore » diffraction angles, and work for X-ray energies of tens to hundreds of kiloelectronvolts. The design is generated and optimized using ray-tracing simulations, and fabricated through laser micromachining. The first prototype was successfully tested at the X17A beamline at the National Synchrotron Light Source, and shows similar performance to simulations, demonstrating gauge volume selection for standard powders, for all diffraction peaks over angles of 2–10°. A similar, but improved, design will be implemented at the X-ray Powder Diffraction beamline at the National Synchrotron Light Source II.« less

THE ENVIRONMENT AND DISTRIBUTION OF EMITTING ELECTRONS AS A FUNCTION OF SOURCE ACTIVITY IN MARKARIAN 421

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mankuzhiyil, Nijil; Ansoldi, Stefano; Persic, Massimo

2011-05-20

For the high-frequency-peaked BL Lac object Mrk 421, we study the variation of the spectral energy distribution (SED) as a function of source activity, from quiescent to active. We use a fully automatized {chi}{sup 2}-minimization procedure, instead of the 'eyeball' procedure more commonly used in the literature, to model nine SED data sets with a one-zone synchrotron self-Compton (SSC) model and examine how the model parameters vary with source activity. The latter issue can finally be addressed now, because simultaneous broadband SEDs (spanning from optical to very high energy photon) have finally become available. Our results suggest that in Mrkmore » 421 the magnetic field (B) decreases with source activity, whereas the electron spectrum's break energy ({gamma}{sub br}) and the Doppler factor ({delta}) increase-the other SSC parameters turn out to be uncorrelated with source activity. In the SSC framework, these results are interpreted in a picture where the synchrotron power and peak frequency remain constant with varying source activity, through a combination of decreasing magnetic field and increasing number density of {gamma} {<=} {gamma}{sub br} electrons: since this leads to an increased electron-photon scattering efficiency, the resulting Compton power increases, and so does the total (= synchrotron plus Compton) emission.« less

Ultra-spatial synchrotron radiation for imaging molecular chemical structure: Applications in plant and animal studies

DOE PAGES

Yu, Peiqiang

2007-01-01

Synchrotron-based Fourier transform infrared microspectroscopy (S-FTIR) has been developed as a rapid, direct, non-destructive, bioanalytical technique. This technique takes advantage of synchrotron light brightness and small effective source size and is capable of exploring the molecular chemical features and make-up within microstructures of a biological tissue without destruction of inherent structures at ultra-spatial resolutions within cellular dimension. To date there has been very little application of this advanced synchrotron technique to the study of plant and animal tissues' inherent structure at a cellular or subcellular level. In this article, a novel approach was introduced to show the potential of themore » newly developed, advanced synchrotron-based analytical technology, which can be used to reveal molecular structural-chemical features of various plant and animal tissues.« less

Applications of synchrotron-based spectroscopic techniques in studying nucleic acids and nucleic acid-functionalized nanomaterials

PubMed Central

Wu, Peiwen; Yu, Yang; McGhee, Claire E.; Tan, Li Huey

2014-01-01

In this review, we summarize recent progresses in the application of synchrotron-based spectroscopic techniques for nucleic acid research that takes advantage of high-flux and high-brilliance electromagnetic radiation from synchrotron sources. The first section of the review focuses on the characterization of the structure and folding processes of nucleic acids using different types of synchrotron-based spectroscopies, such as X-ray absorption spectroscopy, X-ray emission spectroscopy, X-ray photoelectron spectroscopy, synchrotron radiation circular dichroism, X-ray footprinting and small-angle X-ray scattering. In the second section, the characterization of nucleic acid-based nanostructures, nucleic acid-functionalized nanomaterials and nucleic acid-lipid interactions using these spectroscopic techniques is summarized. Insights gained from these studies are described and future directions of this field are also discussed. PMID:25205057

Applications of synchrotron-based spectroscopic techniques in studying nucleic acids and nucleic acid-functionalized nanomaterials

DOE PAGES

Wu, Peiwen; Yu, Yang; McGhee, Claire E.; ...

2014-09-10

In this paper, we summarize recent progress in the application of synchrotron-based spectroscopic techniques for nucleic acid research that takes advantage of high-flux and high-brilliance electromagnetic radiation from synchrotron sources. The first section of the review focuses on the characterization of the structure and folding processes of nucleic acids using different types of synchrotron-based spectroscopies, such as X-ray absorption spectroscopy, X-ray emission spectroscopy, X-ray photoelectron spectroscopy, synchrotron radiation circular dichroism, X-ray footprinting and small-angle X-ray scattering. In the second section, the characterization of nucleic acid-based nanostructures, nucleic acid-functionalized nanomaterials and nucleic acid-lipid interactions using these spectroscopic techniques is summarized. Insightsmore » gained from these studies are described and future directions of this field are also discussed.« less

Polarized Negative Light Ions at the Cooler Synchrotron COSY/Juelich

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gebel, R.; Felden, O.; Rossen, P. von

2005-04-06

The polarized ion source at the cooler synchrotron facility COSY of the research centre Juelich in Germany delivers negative polarized protons or deuterons for medium energy experiments. The polarized ion source, originally built by the universities of Bonn, Erlangen and Cologne, is based on the colliding beams principle, using after an upgrade procedure an intense pulsed neutralized caesium beam for charge exchange with a pulsed highly polarized hydrogen beam. The source is operated at 0.5 Hz repetition rate with 20 ms pulse length, which is the maximum useful length for the injection into the synchrotron. Routinely intensities of 20 {mu}Amore » are delivered for injection into the cyclotron of the COSY facility. For internal targets the intensity of 2 mA and a polarization up to 90% have been reached. Reliable long-term operation for experiments at COSY for up to 9 weeks has been achieved. Since 2003 polarized deuterons with different combinations of vector and tensor polarization were delivered to experiments.« less

Refurbishment of a used in-vacuum undulator from the National Synchrotron Light Source for the National Synchrotron Light Source-II ring

DOE PAGES

Tanabe, Toshiya; Bassan, Harmanpreet; Broadbent, Andrew; ...

2017-08-01

The National Synchrotron Light Source (NSLS) ceased operation in September 2014 and was succeeded by NSLS-II. There were four in-vacuum undulators (IVUs) in operation at NSLS. The most recently constructed IVU for NSLS was the mini-gap undulator (MGU-X25, to be renamed IVU18 for NSLS-II), which was constructed in 2006. This device was selected to be reused for the New York Structural Biology Consortium Microdiffraction beamline at NSLS-II. At the time of construction, IVU18 was a state-of-the-art undulator designed to be operated as a cryogenic permanent-magnet undulator. Due to the more stringent field quality and impedance requirements of the NSLS-II ring,more » the transition region was redesigned. The control system was also updated to NSLS-II specifications. As a result, this paper reports the details of the IVU18 refurbishment activities including additional magnetic measurement and tuning.« less

Trace element abundance determinations by Synchrotron X Ray Fluorescence (SXRF) on returned comet nucleus mineral grains

NASA Technical Reports Server (NTRS)

Flynn, G. J.; Sutton, S. R.

1989-01-01

Trace element analyses were performed on bulk cosmic dust particles by Proton Induced X Ray Emission (PIXE) and Synchrotron X Ray Fluorescence (SXRF). When present at or near chondritic abundances the trace elements K, Ti, Cr, Mn, Cu, Zn, Ga, Ge, Se, and Br are presently detectable by SXRF in particles of 20 micron diameter. Improvements to the SXRF analysis facility at the National Synchrotron Light Source presently underway should increase the range of detectable elements and permit the analysis of smaller samples. In addition the Advanced Photon Source will be commissioned at Argonne National Laboratory in 1995. This 7 to 8 GeV positron storage ring, specifically designed for high-energy undulator and wiggler insertion devices, will be an ideal source for an x ray microprobe with one micron spatial resolution and better than 100 ppb elemental sensitivity for most elements. Thus trace element analysis of individual micron-sized grains should be possible by the time of the comet nucleus sample return mission.

Refurbishment of a used in-vacuum undulator from the National Synchrotron Light Source for the National Synchrotron Light Source-II ring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanabe, Toshiya; Bassan, Harmanpreet; Broadbent, Andrew

The National Synchrotron Light Source (NSLS) ceased operation in September 2014 and was succeeded by NSLS-II. There were four in-vacuum undulators (IVUs) in operation at NSLS. The most recently constructed IVU for NSLS was the mini-gap undulator (MGU-X25, to be renamed IVU18 for NSLS-II), which was constructed in 2006. This device was selected to be reused for the New York Structural Biology Consortium Microdiffraction beamline at NSLS-II. At the time of construction, IVU18 was a state-of-the-art undulator designed to be operated as a cryogenic permanent-magnet undulator. Due to the more stringent field quality and impedance requirements of the NSLS-II ring,more » the transition region was redesigned. The control system was also updated to NSLS-II specifications. As a result, this paper reports the details of the IVU18 refurbishment activities including additional magnetic measurement and tuning.« less

A Mo-anode-based in-house source for small-angle X-ray scattering measurements of biological macromolecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruetzel, Linda K.; Fischer, Stefan; Salditt, Annalena

2016-02-15

We demonstrate the use of a molybdenum-anode-based in-house small-angle X-ray scattering (SAXS) setup to study biological macromolecules in solution. Our system consists of a microfocus X-ray tube delivering a highly collimated flux of 2.5 × 10{sup 6} photons/s at a beam size of 1.2 × 1.2 mm{sup 2} at the collimation path exit and a maximum beam divergence of 0.16 mrad. The resulting observable scattering vectors q are in the range of 0.38 Å{sup −1} down to 0.009 Å{sup −1} in SAXS configuration and of 0.26 Å{sup −1} up to 5.7 Å{sup −1} in wide-angle X-ray scattering (WAXS) mode. Tomore » determine the capabilities of the instrument, we collected SAXS data on weakly scattering biological macromolecules including proteins and a nucleic acid sample with molecular weights varying from ∼12 to 69 kDa and concentrations of 1.5–24 mg/ml. The measured scattering data display a high signal-to-noise ratio up to q-values of ∼0.2 Å{sup −1} allowing for an accurate structural characterization of the samples. Moreover, the in-house source data are of sufficient quality to perform ab initio 3D structure reconstructions that are in excellent agreement with the available crystallographic structures. In addition, measurements for the detergent decyl-maltoside show that the setup can be used to determine the size, shape, and interactions (as characterized by the second virial coefficient) of detergent micelles. This demonstrates that the use of a Mo-anode based in-house source is sufficient to determine basic geometric parameters and 3D shapes of biomolecules and presents a viable alternative to valuable beam time at third generation synchrotron sources.« less

Glycoscience@Synchrotron: Synchrotron radiation applied to structural glycoscience

PubMed Central

de Sanctis, Daniele

2017-01-01

Synchrotron radiation is the most versatile way to explore biological materials in different states: monocrystalline, polycrystalline, solution, colloids and multiscale architectures. Steady improvements in instrumentation have made synchrotrons the most flexible intense X-ray source. The wide range of applications of synchrotron radiation is commensurate with the structural diversity and complexity of the molecules and macromolecules that form the collection of substrates investigated by glycoscience. The present review illustrates how synchrotron-based experiments have contributed to our understanding in the field of structural glycobiology. Structural characterization of protein–carbohydrate interactions of the families of most glycan-interacting proteins (including glycosyl transferases and hydrolases, lectins, antibodies and GAG-binding proteins) are presented. Examples concerned with glycolipids and colloids are also covered as well as some dealing with the structures and multiscale architectures of polysaccharides. Insights into the kinetics of catalytic events observed in the crystalline state are also presented as well as some aspects of structure determination of protein in solution. PMID:28684994

Control and performance of the AGS and AGS Booster Main Magnet Power Supplies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reece, R.K.; Casella, R.; Culwick, B.

1993-06-01

Techniques for precision control of the main magnet power supplies for the AGS and AGS Booster synchrotron will be discussed. Both synchrotrons are designed to operate in a Pulse-to-Pulse Modulation (PPM) environment with a Supercycle Generator defining and distributing global timing events for the AGS Facility. Details of modelling, real-time feedback and feedforward systems, generation and distribution of real time field data, operational parameters and an overview of performance for both machines are included.

Control and performance of the AGS and AGS Booster Main Magnet Power Supplies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reece, R.K.; Casella, R.; Culwick, B.

1993-01-01

Techniques for precision control of the main magnet power supplies for the AGS and AGS Booster synchrotron will be discussed. Both synchrotrons are designed to operate in a Pulse-to-Pulse Modulation (PPM) environment with a Supercycle Generator defining and distributing global timing events for the AGS Facility. Details of modelling, real-time feedback and feedforward systems, generation and distribution of real time field data, operational parameters and an overview of performance for both machines are included.

Rapid, non-destructive coral paleothermometry by synchrotron XR

NASA Astrophysics Data System (ADS)

Tangri, N.; Mehta, A.; Marks, R.; Dunbar, R. B.

2016-12-01

We present advances in the use of synchrotron x-ray fluorescence (XRF) to recover climate signals from coral exoskeleton. Corals record sea surface temperature (SST), salinity, and other environmental conditions in the density and composition of their exoskeletons; in particular, SST is reflected in both the Sr/Ca ratio and the annual density banding. Synchrotron XRF has previously been used to examine the fine-scaled variability of Sr concentrations in the exoskeleton structure, but has not yet yielded any long-term SST reconstructions. Modern XRF techniques allow the detection of sub-ppm trace element concentrations and appear ideally suited to long climate reconstructions, as they are non-destructive, high-resolution (250 um) and potentially quite rapid ( 40 years of sample in 24 hours of instrument time). The low Sr content of the coral and its low change in concentration require a high brightness synchrotron source to generate a high signal-to-background ratio. However, difficulties arise from the local heterogeneity of Sr that is unrelated to environmental conditions. These variations of biological origin in Sr concentrations often mask the smaller-amplitude, annual and interannual SST signals. The challenge is to normalize the local variability in order to extract the climate signal. Other techniques have normalized against Ca, but in XRF the Ca signal is sensitive to only the surface 50 um of material, whereas the Sr signal comes from 1mm, so the values are not comparable. Instead, we normalize against density as calculated from beam transmission. We also explore the use of Rb normalization to filter out collection artifacts. Both Sr and Rb show strong annual signals and interesting departures from the density signal. Finally, we pair the XRF results with δ18O measurements to recover a convincing record of SST variation. Although challenges remain, we believe that synchrotron XRF techniques hold considerable promise to rapidly and accurately recover climate signals from corals.

Omega Dante Soft X-Ray Power Diagnostic Component Calibration at the National Synchrotron Light Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campbell, K; Weber, F; Dewald, E

2004-04-15

The Dante soft x-ray spectrometer installed on the Omega laser facility at the Laboratory for Laser Energetics, University of Rochester is a twelve-channel filter-edge defined x-ray power diagnostic. It is used to measure the absolute flux from direct drive, indirect drive (hohlraums) and other plasma sources. Calibration efforts using two beam lines, U3C (50eV-1keV) and X8A (1keV-6keV) at the National Synchrotron Light Source (NSLS) have been implemented to insure the accuracy of these measurements. We have calibrated vacuum x-ray diodes, mirrors and filters.

The stopped-drop method: a novel setup for containment-free and time-resolved measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schiener, Andreas; Seifert, Soenke; Magerl, Andreas

2016-03-01

A novel setup for containment-free time-resolved experiments at a free-hanging drop is reported. Within a dead-time of 100 ms a drop of mixed reactant solutions is formed and the time evolution of a reaction can be followed from thereon by various techniques. As an example, a small-angle X-ray scattering study on the formation mechanism of EDTA-stabilized CdS both at a synchrotron and a laboratory X-ray source is presented here. While the evolution can be followed with one drop only at a synchrotron source, a stroboscopic mode with many drops is preferable for the laboratory source.

Numerical calculations of spectral turnover and synchrotron self-absorption in CSS and GPS radio sources

NASA Astrophysics Data System (ADS)

Jeyakumar, S.

2016-06-01

The dependence of the turnover frequency on the linear size is presented for a sample of Giga-hertz Peaked Spectrum and Compact Steep Spectrum radio sources derived from complete samples. The dependence of the luminosity of the emission at the peak frequency with the linear size and the peak frequency is also presented for the galaxies in the sample. The luminosity of the smaller sources evolve strongly with the linear size. Optical depth effects have been included to the 3D model for the radio source of Kaiser to study the spectral turnover. Using this model, the observed trend can be explained by synchrotron self-absorption. The observed trend in the peak-frequency-linear-size plane is not affected by the luminosity evolution of the sources.

On the Possibility of Acceleration of Polarized Protons in the Synchrotron Nuclotron

NASA Astrophysics Data System (ADS)

Shatunov, Yu. M.; Koop, I. A.; Otboev, A. V.; Mane, S. P.; Shatunov, P. Yu.

2018-05-01

One of the main tasks of the NICA project is to produce colliding beams of polarized protons. It is planned to accelerate polarized protons from the source to the maximum energy in the existing proton synchrotron. We consider all depolarizing spin resonances in the Nuclotron and propose methods to overcome them.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramadhar, Timothy R.; Zheng, Shao-Liang; Chen, Yu-Sheng

This report describes complete practical guidelines and insights for the crystalline sponge method, which have been derived through the first use of synchrotron radiation on these systems, and includes a procedure for faster synthesis of the sponges. These guidelines will be applicable to crystal sponge data collected at synchrotrons or in-house facilities, and will allow researchers to obtain reliable high-quality data and construct chemically and physically sensible models for guest structural determination. A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported.more » The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collection times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flack x absolute stereochemical determination parameter to date for these systems. The structures did not require the use of PLATON/SQUEEZE or other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine occupancies, discussion of the proper use of geometric and anisotropic displacement parameter restraints and constraints, and whether to perform solvent squeezing/masking. The single-crystal-to-single-crystal transformation process for the crystal sponges is also discussed. The presented general guidelines will be invaluable for researchers interested in using the crystalline sponge method at in-house diffraction or synchrotron facilities, will facilitate the collection and analysis of reliable high-quality data, and will allow construction of chemically and physically sensible models for guest structural determination.« less

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

NASA Astrophysics Data System (ADS)

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.

Possibilities for serial femtosecond crystallography sample delivery at future light sourcesa)

PubMed Central

Chavas, L. M. G.; Gumprecht, L.; Chapman, H. N.

2015-01-01

Serial femtosecond crystallography (SFX) uses X-ray pulses from free-electron laser (FEL) sources that can outrun radiation damage and thereby overcome long-standing limits in the structure determination of macromolecular crystals. Intense X-ray FEL pulses of sufficiently short duration allow the collection of damage-free data at room temperature and give the opportunity to study irreversible time-resolved events. SFX may open the way to determine the structure of biological molecules that fail to crystallize readily into large well-diffracting crystals. Taking advantage of FELs with high pulse repetition rates could lead to short measurement times of just minutes. Automated delivery of sample suspensions for SFX experiments could potentially give rise to a much higher rate of obtaining complete measurements than at today's third generation synchrotron radiation facilities, as no crystal alignment or complex robotic motions are required. This capability will also open up extensive time-resolved structural studies. New challenges arise from the resulting high rate of data collection, and in providing reliable sample delivery. Various developments for fully automated high-throughput SFX experiments are being considered for evaluation, including new implementations for a reliable yet flexible sample environment setup. Here, we review the different methods developed so far that best achieve sample delivery for X-ray FEL experiments and present some considerations towards the goal of high-throughput structure determination with X-ray FELs. PMID:26798808

Measurement of aspheric mirror by nanoprofiler using normal vector tracing

NASA Astrophysics Data System (ADS)

Kitayama, Takao; Shiraji, Hiroki; Yamamura, Kazuya; Endo, Katsuyoshi

2016-09-01

Aspheric or free-form optics with high accuracy are necessary in many fields such as third-generation synchrotron radiation and extreme-ultraviolet lithography. Therefore the demand of measurement method for aspherical or free-form surface with nanometer accuracy increases. Purpose of our study is to develop a non-contact measurement technology for aspheric or free-form surfaces directly with high repeatability. To achieve this purpose we have developed threedimensional Nanoprofiler which detects normal vectors of sample surface. The measurement principle is based on the straightness of laser light and the accurate motion of rotational goniometers. This machine consists of four rotational stages, one translational stage and optical head which has the quadrant photodiode (QPD) and laser source. In this measurement method, we conform the incident light beam to reflect the beam by controlling five stages and determine the normal vectors and the coordinates of the surface from signal of goniometers, translational stage and QPD. We can obtain three-dimensional figure from the normal vectors and their coordinates by surface reconstruction algorithm. To evaluate performance of this machine we measure a concave aspheric mirror with diameter of 150 mm. As a result we achieve to measure large area of 150mm diameter. And we observe influence of systematic errors which the machine has. Then we simulated the influence and subtracted it from measurement result.

MICROSCANNING XRF, XANES, AND XRD STUDIES OF THEDECORATED SURFACE OF ROMAN TERRA SIGILLATA CERAMICS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mirguet, C.; Sciau, P.; Goudeau, P.

Different microscanning synchrotron techniques were used to better understand the elaboration process and origins of Terra Sigillata potteries from the Roman period. A mixture Gallic slip sample cross-section showing red and yellow colors was studied. The small (micron) size of the X-ray beam available at Stanford Synchrotron Radiation Laboratory (SSRL) and Advanced Light Source (ALS) synchrotron sources, coupled with the use of a sample scanning stage allowed us to spatially resolve the distribution of the constitutive mineral phases related to the chemical composition. Results show that red color is a result of iron-rich hematite crystals and the yellow part ismore » a result of the presence of Ti-rich rutile-type phase (brookite). Volcanic-type clay is at the origin of these marble Terra Sigillata.« less

Mix-and-diffuse serial synchrotron crystallography

DOE PAGES

Beyerlein, Kenneth R.; Dierksmeyer, Dennis; Mariani, Valerio; ...

2017-10-09

Unravelling the interaction of biological macromolecules with ligands and substrates at high spatial and temporal resolution remains a major challenge in structural biology. The development of serial crystallography methods at X-ray free-electron lasers and subsequently at synchrotron light sources allows new approaches to tackle this challenge. Here, a new polyimide tape drive designed for mix-and-diffuse serial crystallography experiments is reported. The structure of lysozyme bound by the competitive inhibitor chitotriose was determined using this device in combination with microfluidic mixers. The electron densities obtained from mixing times of 2 and 50 s show clear binding of chitotriose to the enzymemore » at a high level of detail. Here, the success of this approach shows the potential for high-throughput drug screening and even structural enzymology on short timescales at bright synchrotron light sources.« less

Mix-and-diffuse serial synchrotron crystallography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beyerlein, Kenneth R.; Dierksmeyer, Dennis; Mariani, Valerio

Unravelling the interaction of biological macromolecules with ligands and substrates at high spatial and temporal resolution remains a major challenge in structural biology. The development of serial crystallography methods at X-ray free-electron lasers and subsequently at synchrotron light sources allows new approaches to tackle this challenge. Here, a new polyimide tape drive designed for mix-and-diffuse serial crystallography experiments is reported. The structure of lysozyme bound by the competitive inhibitor chitotriose was determined using this device in combination with microfluidic mixers. The electron densities obtained from mixing times of 2 and 50 s show clear binding of chitotriose to the enzymemore » at a high level of detail. Here, the success of this approach shows the potential for high-throughput drug screening and even structural enzymology on short timescales at bright synchrotron light sources.« less

National Synchrotron Light Source II storage ring vacuum systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hseuh, Hsiao-Chaun, E-mail: hseuh@bnl.gov; Hetzel, Charles; Leng, Shuwei

2016-05-15

The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. The majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. This paper presents themore » design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.« less

A Model Describing Stable Coherent Synchrotron Radiation in Storage Rings

NASA Astrophysics Data System (ADS)

Sannibale, F.; Byrd, J. M.; Loftsdóttir, Á.; Venturini, M.; Abo-Bakr, M.; Feikes, J.; Holldack, K.; Kuske, P.; Wüstefeld, G.; Hübers, H.-W.; Warnock, R.

2004-08-01

We present a model describing high power stable broadband coherent synchrotron radiation (CSR) in the terahertz frequency region in an electron storage ring. The model includes distortion of bunch shape from the synchrotron radiation (SR), which enhances higher frequency coherent emission, and limits to stable emission due to an instability excited by the SR wakefield. It gives a quantitative explanation of several features of the recent observations of CSR at the BESSYII storage ring. We also use this model to optimize the performance of a source for stable CSR emission.

Focusing of white synchrotron radiation using large-acceptance cylindrical refractive lenses made of single – crystal diamond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polikarpov, M., E-mail: polikarpov.maxim@mail.ru; Snigireva, I.; Snigirev, A.

2016-07-27

Large-aperture cylindrical refractive lenses were manufactured by laser cutting of single-crystal diamond. Five linear single lenses with apertures of 1 mm and the depth of the structure of 1.2 mm were fabricated and tested at the ESRF ID06 beamline performing the focusing of white-beam synchrotron radiation. Uniform linear focus was stable during hours of exposure, representing such lenses as pre-focusing and collimating devices suitable for the front-end sections of today synchrotron radiation sources.

Updating the Synchrotron Radiation Monitor at TLS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuo, C. H.; Hsu, S. Y.; Wang, C. J.

2007-01-19

The synchrotron radiation monitor provides useful information to support routine operation and physics experiments using the beam. Precisely knowing the profile of the beam helps to improve machine performance. The synchrotron radiation monitor at the Taiwan Light Source (TLS) was recently upgraded. The optics and modeling were improved to increase the accuracy of measurement in the small beam size. A high-performance IEEE-1394 digital CCD camera was used to improve the quality of images and extend the dynamic range of measurement. The image analysis is also improved. This report summarizes status and results.

Progress toward the Wisconsin Free Electron Laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bisognano, Joseph; Eisert, D; Fisher, M V

2011-03-01

The University of Wisconsin-Madison/Synchrotron Radiation Center is advancing its design for a seeded VUV/soft X-ray Free Electron Laser facility called WiFEL. To support this vision of an ultimate light source, we are pursuing a program of strategic R&D addressing several crucial elements. This includes development of a high repetition rate, VHF superconducting RF electron gun, R&D on photocathode materials by ARPES studies, and evaluation of FEL facility architectures (e.g., recirculation, compressor scenarios, CSR dechirping, undulator technologies) with the specific goal of cost containment. Studies of high harmonic generation for laser seeding are also planned.

Propagation-based phase-contrast x-ray tomography of cochlea using a compact synchrotron source.

PubMed

Töpperwien, Mareike; Gradl, Regine; Keppeler, Daniel; Vassholz, Malte; Meyer, Alexander; Hessler, Roland; Achterhold, Klaus; Gleich, Bernhard; Dierolf, Martin; Pfeiffer, Franz; Moser, Tobias; Salditt, Tim

2018-03-21

We demonstrate that phase retrieval and tomographic imaging at the organ level of small animals can be advantageously carried out using the monochromatic radiation emitted by a compact x-ray light source, without further optical elements apart from source and detector. This approach allows to carry out microtomography experiments which - due to the large performance gap with respect to conventional laboratory instruments - so far were usually limited to synchrotron sources. We demonstrate the potential by mapping the functional soft tissue within the guinea pig and marmoset cochlea, including in the latter case an electrical cochlear implant. We show how 3d microanatomical studies without dissection or microscopic imaging can enhance future research on cochlear implants.

Single-energy pediatric chest computed tomography with spectral filtration at 100 kVp: effects on radiation parameters and image quality.

PubMed

Bodelle, Boris; Fischbach, Constanze; Booz, Christian; Yel, Ibrahim; Frellesen, Claudia; Kaup, Moritz; Beeres, Martin; Vogl, Thomas J; Scholtz, Jan-Erik

2017-06-01

Most of the applied radiation dose at CT is in the lower photon energy range, which is of limited diagnostic importance. To investigate image quality and effects on radiation parameters of 100-kVp spectral filtration single-energy chest CT using a tin-filter at third-generation dual-source CT in comparison to standard 100-kVp chest CT. Thirty-three children referred for a non-contrast chest CT performed on a third-generation dual-source CT scanner were examined at 100 kVp with a dedicated tin filter with a tube current-time product resulting in standard protocol dose. We compared resulting images with images from children examined using standard single-source chest CT at 100 kVp. We assessed objective and subjective image quality and compared radiation dose parameters. Radiation dose was comparable for children 5 years old and younger, and it was moderately decreased for older children when using spectral filtration (P=0.006). Effective tube current increased significantly (P=0.0001) with spectral filtration, up to a factor of 10. Signal-to-noise ratio and image noise were similar for both examination techniques (P≥0.06). Subjective image quality showed no significant differences (P≥0.2). Using 100-kVp spectral filtration chest CT in children by means of a tube-based tin-filter on a third-generation dual-source CT scanner increases effective tube current up to a factor of 10 to provide similar image quality at equivalent dose compared to standard single-source CT without spectral filtration.

First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission

NASA Technical Reports Server (NTRS)

Bennett, C. L.; Hill, R. S.; Hinshaw, G.; Nolta, M. R.; Odegard, N.; Page, L.; Spergel, D. N.; Weiland, J. L.; Wright, E. L.; Halpern, M.

2003-01-01

The WMAP mission has mapped the full sky to determine the geometry, content, and evolution of the universe. Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the cosmic microwave background (CMB) from foreground emission, including diffuse Galactic emission and Galactic and extragalactic point sources. We define masks that excise regions of high foreground emission, so CMB analyses can became out with minimal foreground contamination. We also present maps and spectra of the individual emission components, leading to an improved understanding of Galactic astrophysical processes. The effectiveness of template fits to remove foreground emission from the WMAP data is also examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We use a Maximum Entropy Method to construct a model of the Galactic emission components. The observed total Galactic emission matches the model to less than 1% and the individual model components are accurate to a few percent. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (beta(sub s) approx. -2.5) near star-forming regions, especially in the plane, and steepest (beta(sub s) approx. -3) in the halo. This is consistent with a picture of relativistic cosmic ray electron generation in star-forming regions and diffusion and convection within the plane. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to beta(sub s) less than -3. The modeled thermal dust spectral index is also steep in the WMAP bands, with beta(sub d) approx. = 2.2. Our model is driven to these conclusions by the low level of total foreground contamination at approx. 60 GHz. Microwave and Ha measurements of the ionized gas agree well with one another at about the expected levels. Spinning dust emission is limited to less than 5% of the Ka-band foreground emission. A catalog of 208 point sources is presented. The reliability of the catalog is 98%, i.e., we expect five of the 208 sources to be statistically spurious. The mean spectral index of the point sources is alpha approx. 0(beta approx. -2). Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0 +/- 1.4) x 10(exp -3)micro sq K sr at Q-band and negligible levels at V-band and W-band. The Sunyaev-Zeldovich effect is shown to be a negligible "contamination" to the maps.

Fast synchrotron and FEL beam monitors based on single-crystal diamond detectors and InGaAs/InAlAs quantum well devices

NASA Astrophysics Data System (ADS)

Antonelli, M.; Di Fraia, M.; Carrato, S.; Cautero, G.; Menk, R. H.; Jark, W. H.; Ganbold, T.; Biasiol, G.; Callegari, C.; Coreno, M.; De Sio, A.; Pace, E.

2013-12-01

Simultaneous photon-beam position and intensity monitoring is becoming of increasing importance for new-generation synchrotron radiation sources and free-electron lasers (FEL). Thus, novel concepts of beam diagnostics are required in order to keep such beams under control. From this perspective diamond is a promising material for the production of semitransparent in situ photon beam monitors, which can withstand the high dose rates occurring in such radiation facilities. Here, we report on the development of freestanding, single-crystal chemical-vapor-deposited diamond detectors with segmented electrodes. Due to their direct, low-energy band gap, InGaAs quantum well devices operated at room temperature may also be used as fast detectors for photons ranging from visible to X-ray. These features are valuable in low-energy and time-resolved FEL applications. In particular, a novel segmented InGaAs/InAlAs device has been developed and will be discussed. Dedicated measurements carried out on both these devices at the Elettra Synchrotron show their capability to monitor the position and the intensity of the photon beam with bunch-by-bunch temporal performances. Furthermore, preliminary tests have been performed on diamond detectors at the Fermi FEL, extracting quantitative intensity and position information for 100-fs-wide FEL pulses with a photon energy of 28.8 eV.

HESS J1943+213: A Non-classical High-frequency-peaked BL Lac Object

NASA Astrophysics Data System (ADS)

Straal, S. M.; Gabányi, K. É.; van Leeuwen, J.; Clarke, T. E.; Dubner, G.; Frey, S.; Giacani, E.; Paragi, Z.

2016-05-01

HESS J1943+213 is an unidentified TeV source that is likely a high-frequency-peaked BL Lac (HBL) object, but that is also compatible with a pulsar wind nebula (PWN) nature. Each of these enormously different astronomical interpretations is supported by some of the observed unusual characteristics. In order to finally classify and understand this object, we took a three-pronged approach, through time-domain, high angular resolution, and multi-frequency radio studies. First, our deep time-domain observations with the Arecibo telescope failed to uncover the putative pulsar powering the proposed PWN. We conclude with ˜70% certainty that HESS J1943+213 does not host a pulsar. Second, long-baseline interferometry of the source with e-MERLIN at 1.5 and 5 GHz shows only a core, that is, a point source at ˜ 1-100 mas resolution. Its 2013 flux density is about one-third lower than that detected in the 2011 observations with similar resolution. This radio variability of the core strengthens the HBL object hypothesis. Third, additional evidence against the PWN scenario comes from the radio spectrum we compiled. The extended structure follows a power-law behavior with spectral index α \\=\\-0.54+/- 0.04 while the core component displays a flat spectrum (α \\=\\-0.03+/- 0.03). In contrast, the radio synchrotron emission of PWNe predicts a single power-law distribution. Overall, we rule out the PWN hypothesis and conclude that the source is a BL Lac object. The consistently high fraction (70%) of the flux density from the extended structure then leads us to conclude that HESS J1943+213 must be a non-classical HBL object.

Towards protein-crystal centering using second-harmonic generation (SHG) microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kissick, David J.; Dettmar, Christopher M.; Becker, Michael

2013-05-01

The potential of second-harmonic generation (SHG) microscopy for automated crystal centering to guide synchrotron X-ray diffraction of protein crystals has been explored. The potential of second-harmonic generation (SHG) microscopy for automated crystal centering to guide synchrotron X-ray diffraction of protein crystals was explored. These studies included (i) comparison of microcrystal positions in cryoloops as determined by SHG imaging and by X-ray diffraction rastering and (ii) X-ray structure determinations of selected proteins to investigate the potential for laser-induced damage from SHG imaging. In studies using β{sub 2} adrenergic receptor membrane-protein crystals prepared in lipidic mesophase, the crystal locations identified by SHGmore » images obtained in transmission mode were found to correlate well with the crystal locations identified by raster scanning using an X-ray minibeam. SHG imaging was found to provide about 2 µm spatial resolution and shorter image-acquisition times. The general insensitivity of SHG images to optical scatter enabled the reliable identification of microcrystals within opaque cryocooled lipidic mesophases that were not identified by conventional bright-field imaging. The potential impact of extended exposure of protein crystals to five times a typical imaging dose from an ultrafast laser source was also assessed. Measurements of myoglobin and thaumatin crystals resulted in no statistically significant differences between structures obtained from diffraction data acquired from exposed and unexposed regions of single crystals. Practical constraints for integrating SHG imaging into an active beamline for routine automated crystal centering are discussed.« less

In Situ Local Measurement of Austenite Mechanical Stability and Transformation Behavior in Third-Generation Advanced High-Strength Steels

NASA Astrophysics Data System (ADS)

Abu-Farha, Fadi; Hu, Xiaohua; Sun, Xin; Ren, Yang; Hector, Louis G.; Thomas, Grant; Brown, Tyson W.

2018-05-01

Austenite mechanical stability, i.e., retained austenite volume fraction (RAVF) variation with strain, and transformation behavior were investigated for two third-generation advanced high-strength steels (3GAHSS) under quasi-static uniaxial tension: a 1200 grade, two-phase medium Mn (10 wt pct) TRIP steel, and a 980 grade, three-phase TRIP steel produced with a quenching and partitioning heat treatment. The medium Mn (10 wt pct) TRIP steel deforms inhomogeneously via propagative instabilities (Lüders and Portevin Le Châtelier-like bands), while the 980 grade TRIP steel deforms homogenously up to necking. The dramatically different deformation behaviors of these steels required the development of a new in situ experimental technique that couples volumetric synchrotron X-ray diffraction measurement of RAVF with surface strain measurement using stereo digital image correlation over the beam impingement area. Measurement results with the new technique are compared to those from a more conventional approach wherein strains are measured over the entire gage region, while RAVF measurement is the same as that in the new technique. A determination is made as to the appropriateness of the different measurement techniques in measuring the transformation behaviors for steels with homogeneous and inhomogeneous deformation behaviors. Extension of the new in situ technique to the measurement of austenite transformation under different deformation modes and to higher strain rates is discussed.

In Situ Local Measurement of Austenite Mechanical Stability and Transformation Behavior in Third-Generation Advanced High-Strength Steels

NASA Astrophysics Data System (ADS)

Abu-Farha, Fadi; Hu, Xiaohua; Sun, Xin; Ren, Yang; Hector, Louis G.; Thomas, Grant; Brown, Tyson W.

2018-07-01

Austenite mechanical stability, i.e., retained austenite volume fraction (RAVF) variation with strain, and transformation behavior were investigated for two third-generation advanced high-strength steels (3GAHSS) under quasi-static uniaxial tension: a 1200 grade, two-phase medium Mn (10 wt pct) TRIP steel, and a 980 grade, three-phase TRIP steel produced with a quenching and partitioning heat treatment. The medium Mn (10 wt pct) TRIP steel deforms inhomogeneously via propagative instabilities (Lüders and Portevin Le Châtelier-like bands), while the 980 grade TRIP steel deforms homogenously up to necking. The dramatically different deformation behaviors of these steels required the development of a new in situ experimental technique that couples volumetric synchrotron X-ray diffraction measurement of RAVF with surface strain measurement using stereo digital image correlation over the beam impingement area. Measurement results with the new technique are compared to those from a more conventional approach wherein strains are measured over the entire gage region, while RAVF measurement is the same as that in the new technique. A determination is made as to the appropriateness of the different measurement techniques in measuring the transformation behaviors for steels with homogeneous and inhomogeneous deformation behaviors. Extension of the new in situ technique to the measurement of austenite transformation under different deformation modes and to higher strain rates is discussed.

PREFACE: 17th Pan-American Synchrotron Radiation Instrumentation Conference SRI2013

NASA Astrophysics Data System (ADS)

Williams, Gwyn P.; Revesz, Peter; Arp, Uwe

2014-03-01

These proceedings are a collection of the articles presented at the seventeenth Pan-American Synchrotron Radiation Instrumentation Conference SRI2013, held on the campus of the National Institute of Standards and Technology (NIST), located in Gaithersburg, Maryland, United States of America, 19-21 June, 2013. SRI2013 was jointly hosted by the Cornell University Cornell High Energy Synchrotron Source (CHESS), the Thomas Jefferson National Accelerator Facility (Jefferson Lab), and the Synchrotron Ultraviolet Radiation Facility (SURF III) at NIST. This meeting's focus was clearly on instrumentation, thus fulfilling the intent of this SRI meeting series, which was initiated at NIST, then the National Bureau of Standards (NBS), in 1979. SRI2013 hosted more than 150 delegates, despite the new US governmental travel restrictions. This proceedings series aims to be an essential reference work for practitioners in the field. It primarily documents the evolution and development of techniques, but also recent scientific advances, that were presented during the two and a half days of the conference. We are extremely thankful to all the authors who contributed to making these proceedings a volume of reference as well as to the reviewers for their careful reading and constructive recommendations for improving the articles. Great thanks go to Robert Dragoset at NIST, for creating and maintaining the conference website and generating the conference logo. We are also thankful for the excellent support we received from the Conference Program at NIST, especially Kathy Kilmer and Angela Ellis. And we would like to dedicate these proceedings to the memory of Kathy Kilmer, who passed away on 15 October, 2013. NIST will not be the same without her. The Co-Editors: Uwe Arp (SURF/NIST) Peter Reversz (CHESS) Gwyn P Williams (Jefferson Lab)

Mono-energy coronary angiography with a compact light source

NASA Astrophysics Data System (ADS)

Eggl, Elena; Mechlem, Korbinian; Braig, Eva; Kulpe, Stephanie; Dierolf, Martin; Günther, Benedikt; Achterhold, Klaus; Herzen, Julia; Gleich, Bernhard; Rummeny, Ernst; Noël, Peter B.; Pfeiffer, Franz; Muenzel, Daniela

2017-03-01

While conventional x-ray tube sources reliably provide high-power x-ray beams for everyday clinical practice, the broad spectra that are inherent to these sources compromise the diagnostic image quality. For a monochromatic x-ray source on the other hand, the x-ray energy can be adjusted to optimal conditions with respect to contrast and dose. However, large-scale synchrotron sources impose high spatial and financial demands, making them unsuitable for clinical practice. During the last decades, research has brought up compact synchrotron sources based on inverse Compton scattering, which deliver a highly brilliant, quasi-monochromatic, tunable x-ray beam, yet fitting into a standard laboratory. One application that could benefit from the invention of these sources in clinical practice is coronary angiography. Being an important and frequently applied diagnostic tool, a high number of complications in angiography, such as renal failure, allergic reaction, or hyperthyroidism, are caused by the large amount of iodine-based contrast agent that is required for achieving sufficient image contrast. Here we demonstrate monochromatic angiography of a porcine heart acquired at the MuCLS, the first compact synchrotron source. By means of a simulation, the CNR in a coronary angiography image achieved with the quasi-mono-energetic MuCLS spectrum is analyzed and compared to a conventional x-ray-tube spectrum. The results imply that the improved CNR achieved with a quasi-monochromatic spectrum can allow for a significant reduction of iodine contrast material.

Analysis of monochromatic and quasi-monochromatic X-ray sources in imaging and therapy

NASA Astrophysics Data System (ADS)

Westphal, Maximillian; Lim, Sara; Nahar, Sultana; Orban, Christopher; Pradhan, Anil

2017-04-01

We studied biomedical imaging and therapeutic applications of recently developed quasi-monochromatic and monochromatic X-ray sources. Using the Monte Carlo code GEANT4, we found that the quasi-monochromatic 65 keV Gaussian X-ray spectrum created by inverse Compton scattering with relatavistic electron beams were capable of producing better image contrast with less radiation compared to conventional 120 kV broadband CT scans. We also explored possible experimental detection of theoretically predicted K α resonance fluorescence in high-Z elements using the European Synchrotron Research Facility with a tungsten (Z = 74) target. In addition, we studied a newly developed quasi-monochromatic source generated by converting broadband X-rays to monochromatic K α and β X-rays with a zirconium target (Z = 40). We will further study how these K α and K β dominated spectra can be implemented in conjunction with nanoparticles for targeted therapy. Acknowledgement: Ohio Supercomputer Center, Columbus, OH.

6th international conference on biophysics and synchrotron radiation. Program/Abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pittroff, Connie; Strasser, Susan Barr

1999-08-03

This STI product consists of the Program/Abstracts book that was prepared for the participants in the Sixth International Conference on Biophysics and Synchrotron Radiation that was held August 4-8, 1998, at the Advanced Photon Source, Argonne National Laboratory. This book contains the full conference program and abstracts of the scientific presentations.

Single nano-hole as a new effective nonlinear element for third-harmonic generation

NASA Astrophysics Data System (ADS)

Melentiev, P. N.; Konstantinova, T. V.; Afanasiev, A. E.; Kuzin, A. A.; Baturin, A. S.; Tausenev, A. V.; Konyaschenko, A. V.; Balykin, V. I.

2013-07-01

In this letter, we report on a particularly strong optical nonlinearity at the nanometer scale in aluminum. A strong optical nonlinearity of the third order was demonstrated on a single nanoslit. Single nanoslits of different aspect ratio were excited by a laser pulse (120 fs) at the wavelength 1.5 μm, leading predominantly to third-harmonic generation (THG). It has been shown that strong surface plasmon resonance in a nanoslit allows the realization of an effective nanolocalized source of third-harmonic radiation. We show also that a nanoslit in a metal film has a significant advantage in nonlinear processes over its Babinet complementary nanostructure (nanorod): the effective abstraction of heat in a film with a slit makes it possible to use much higher laser radiation intensities.

Omega Dante soft x-ray power diagnostic component calibration at the National Synchrotron Light Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campbell, K.M.; Weber, F.A.; Dewald, E.L.

2004-10-01

The Dante soft x-ray spectrometer, installed on the Omega laser facility at the Laboratory for Laser Energetics, University of Rochester, is a 12-channel filter-edge defined soft x-ray power diagnostic. It is used to measure the spectrally resolved, absolute flux from direct drive, indirect drive (hohlraums) and other plasma sources. Dante component calibration efforts using two beam lines, U3C (50 eV-1 keV) and X8A (1-6 keV) at the National Synchrotron Light Source have been implemented to improve the accuracy of these measurements. We have calibrated metallic vacuum x-ray diodes, mirrors and filters.

A smog chamber study coupling a photoionization aerosol electron/ion spectrometer to VUV synchrotron radiation: organic and inorganic-organic mixed aerosol analysis

NASA Astrophysics Data System (ADS)

Baeza-Romero, María Teresa; Gaie-Levrel, Francois; Mahjoub, Ahmed; López-Arza, Vicente; Garcia, Gustavo A.; Nahon, Laurent

2016-07-01

A reaction chamber was coupled to a photoionization aerosol time-of-flight mass spectrometer based on an electron/ion coincidence scheme and applied for on-line analysis of organic and inorganic-organic mixed aerosols using synchrotron tunable vacuum ultraviolet (VUV) photons as the ionization source. In this proof of principle study, both aerosol and gas phase were detected simultaneously but could be differentiated. Present results and perspectives for improvement for this set-up are shown in the study of ozonolysis ([O3] = 0.13-3 ppm) of α-pinene (2-3 ppm), and the uptake of glyoxal upon ammonium sulphate. In this work the ozone concentration was monitored in real time, together with the particle size distributions and chemical composition, the latter taking advantage of the coincidence spectrometer and the tuneability of the synchrotron radiation as a soft VUV ionization source.

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

NASA Astrophysics Data System (ADS)

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.

National Synchrotron Light Source II storage ring vacuum systems

DOE PAGES

Hseuh, Hsiao-Chaun; Hetzel, Charles; Leng, Shuwei; ...

2016-04-05

The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. Also, the majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. Finally, thismore » paper presents the design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.« less

Holographic illuminator for synchrotron-based projection lithography systems

DOEpatents

Naulleau, Patrick P.

2005-08-09

The effective coherence of a synchrotron beam line can be tailored to projection lithography requirements by employing a moving holographic diffuser and a stationary low-cost spherical mirror. The invention is particularly suited for use in an illuminator device for an optical image processing system requiring partially coherent illumination. The illuminator includes: (1) a synchrotron source of coherent or partially coherent radiation which has an intrinsic coherence that is higher than the desired coherence, (2) a holographic diffuser having a surface that receives incident radiation from said source, (3) means for translating the surface of the holographic diffuser in two dimensions along a plane that is parallel to the surface of the holographic diffuser wherein the rate of the motion is fast relative to integration time of said image processing system; and (4) a condenser optic that re-images the surface of the holographic diffuser to the entrance plane of said image processing system.

Pink-beam serial crystallography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meents, A.; Wiedorn, M. O.; Srajer, V.

Serial X-ray crystallography allows macromolecular structure determination at both X-ray free electron lasers (XFELs) and, more recently, synchrotron sources. The time resolution for serial synchrotron crystallography experiments has been limited to millisecond timescales with monochromatic beams. The polychromatic, “pink”, beam provides a more than two orders of magnitude increased photon flux and hence allows accessing much shorter timescales in diffraction experiments at synchrotron sources. Here we report the structure determination of two different protein samples by merging pink-beam diffraction patterns from many crystals, each collected with a single 100 ps X-ray pulse exposure per crystal using a setup optimized formore » very low scattering background. In contrast to experiments with monochromatic radiation, data from only 50 crystals were required to obtain complete datasets. The high quality of the diffraction data highlights the potential of this method for studying irreversible reactions at sub-microsecond timescales using high-brightness X-ray facilities.« less

Pink-beam serial crystallography

DOE PAGES

Meents, A.; Wiedorn, M. O.; Srajer, V.; ...

2017-11-03

Serial X-ray crystallography allows macromolecular structure determination at both X-ray free electron lasers (XFELs) and, more recently, synchrotron sources. The time resolution for serial synchrotron crystallography experiments has been limited to millisecond timescales with monochromatic beams. The polychromatic, “pink”, beam provides a more than two orders of magnitude increased photon flux and hence allows accessing much shorter timescales in diffraction experiments at synchrotron sources. Here we report the structure determination of two different protein samples by merging pink-beam diffraction patterns from many crystals, each collected with a single 100 ps X-ray pulse exposure per crystal using a setup optimized formore » very low scattering background. In contrast to experiments with monochromatic radiation, data from only 50 crystals were required to obtain complete datasets. The high quality of the diffraction data highlights the potential of this method for studying irreversible reactions at sub-microsecond timescales using high-brightness X-ray facilities.« less

Synchrotron-based far-infrared spectroscopy of furan: Rotational analysis of the ν 14 , ν 11 , ν 18 and ν 19 vibrational levels

NASA Astrophysics Data System (ADS)

Tokaryk, D. W.; Culligan, S. D.; Billinghurst, B. E.; van Wijngaarden, J. A.

2011-11-01

Four vibrational levels of the five-membered ring molecule furan (C 4H 4O) have been rotationally analyzed from far-infrared Fourier transform spectra obtained at the Canadian Light Source synchrotron. We found that the low-lying ν14 and ν11 levels at 602.9 and 599.6 cm -1 interact through a second-order Coriolis resonance. This perturbation was characterized through a coupled analysis of the ν14 and ν18 fundamental spectra and the ν18- ν11 band. The ν19 fundamental spectrum was analyzed as well, and the data for all observed bands were combined with previously reported microwave transitions to produce the final fit. The spectra are an excellent demonstration of the high quality of data that can be obtained when far-infrared synchrotron radiation is used as the radiation source in Fourier transform spectroscopy experiments.

Variable Magnification With Kirkpatrick-Baez Optics for Synchrotron X-Ray Microscopy

PubMed Central

Jach, Terrence; Bakulin, Alex S.; Durbin, Stephen M.; Pedulla, Joseph; Macrander, Albert

2006-01-01

We describe the distinction between the operation of a short focal length x-ray microscope forming a real image with a laboratory source (convergent illumination) and with a highly collimated intense beam from a synchrotron light source (Köhler illumination). We demonstrate the distinction with a Kirkpatrick-Baez microscope consisting of short focal length multilayer mirrors operating at an energy of 8 keV. In addition to realizing improvements in the resolution of the optics, the synchrotron radiation microscope is not limited to the usual single magnification at a fixed image plane. Higher magnification images are produced by projection in the limit of geometrical optics with a collimated beam. However, in distinction to the common method of placing the sample behind the optical source of a diverging beam, we describe the situation in which the sample is located in the collimated beam before the optical element. The ultimate limits of this magnification result from diffraction by the specimen and are determined by the sample position relative to the focal point of the optic. We present criteria by which the diffraction is minimized. PMID:27274930

System and method for generating 3D images of non-linear properties of rock formation using surface seismic or surface to borehole seismic or both

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vu, Cung Khac; Nihei, Kurt Toshimi; Johnson, Paul A.

A system and method of characterizing properties of a medium from a non-linear interaction are include generating, by first and second acoustic sources disposed on a surface of the medium on a first line, first and second acoustic waves. The first and second acoustic sources are controllable such that trajectories of the first and second acoustic waves intersect in a mixing zone within the medium. The method further includes receiving, by a receiver positioned in a plane containing the first and second acoustic sources, a third acoustic wave generated by a non-linear mixing process from the first and second acousticmore » waves in the mixing zone; and creating a first two-dimensional image of non-linear properties or a first ratio of compressional velocity and shear velocity, or both, of the medium in a first plane generally perpendicular to the surface and containing the first line, based on the received third acoustic wave.« less

A high-energy, high-flux source of gamma-rays from all-optical non-linear Thomson scattering

NASA Astrophysics Data System (ADS)

Corvan, D. J.; Zepf, M.; Sarri, G.

2016-09-01

γ-Ray sources are among the most fundamental experimental tools currently available to modern physics. As well as the obvious benefits to fundamental research, an ultra-bright source of γ-rays could form the foundation of scanning of shipping containers for special nuclear materials and provide the bases for new types of cancer therapy. However, for these applications to prove viable, γ-ray sources must become compact and relatively cheap to manufacture. In recent years, advances in laser technology have formed the cornerstone of optical sources of high energy electrons which already have been used to generate synchrotron radiation on a compact scale. Exploiting the scattering induced by a second laser, one can further enhance the energy and number of photons produced provided the problems of synchronisation and compact γ-ray detection are solved. Here, we report on the work that has been done in developing an all-optical and hence, compact non-linear Thomson scattering source, including the new methods of synchronisation and compact γ-ray detection. We present evidence of the generation of multi-MeV (maximum 16-18 MeV) and ultra-high brilliance (exceeding 1020 photons s-1mm-2mrad-2 0.1% BW at 15 MeV) γ-ray beams. These characteristics are appealing for the paramount practical applications mentioned above.

Shielding synchrotron light sources: Advantages of circular shield walls tunnels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kramer, S. L.; Ghosh, V. J.; Breitfeller, M.

Third generation high brightness light sources are designed to have low emittance and high current beams, which contribute to higher beam loss rates that will be compensated by Top-Off injection. Shielding for these higher loss rates will be critical to protect the projected higher occupancy factors for the users. Top-Off injection requires a full energy injector, which will demand greater consideration of the potential abnormal beam miss-steering and localized losses that could occur. The high energy electron injection beam produce significantly higher neutron component dose to the experimental floor than lower energy injection and ramped operations. High energy neutrons producedmore » in the forward direction from thin target beam losses are a major component of the dose rate outside the shield walls of the tunnel. The convention has been to provide thicker 90° ratchet walls to reduce this dose to the beam line users. We present an alternate circular shield wall design, which naturally and cost effectively increases the path length for this forward radiation in the shield wall and thereby substantially decreasing the dose rate for these beam losses. Here, this shield wall design will greatly reduce the dose rate to the users working near the front end optical components but will challenge the beam line designers to effectively utilize the longer length of beam line penetration in the shield wall. Additional advantages of the circular shield wall tunnel are that it's simpler to construct, allows greater access to the insertion devices and the upstream in tunnel beam line components, as well as reducing the volume of concrete and therefore the cost of the shield wall.« less

Shielding synchrotron light sources: Advantages of circular shield walls tunnels

DOE PAGES

Kramer, S. L.; Ghosh, V. J.; Breitfeller, M.

2016-04-26

Third generation high brightness light sources are designed to have low emittance and high current beams, which contribute to higher beam loss rates that will be compensated by Top-Off injection. Shielding for these higher loss rates will be critical to protect the projected higher occupancy factors for the users. Top-Off injection requires a full energy injector, which will demand greater consideration of the potential abnormal beam miss-steering and localized losses that could occur. The high energy electron injection beam produce significantly higher neutron component dose to the experimental floor than lower energy injection and ramped operations. High energy neutrons producedmore » in the forward direction from thin target beam losses are a major component of the dose rate outside the shield walls of the tunnel. The convention has been to provide thicker 90° ratchet walls to reduce this dose to the beam line users. We present an alternate circular shield wall design, which naturally and cost effectively increases the path length for this forward radiation in the shield wall and thereby substantially decreasing the dose rate for these beam losses. Here, this shield wall design will greatly reduce the dose rate to the users working near the front end optical components but will challenge the beam line designers to effectively utilize the longer length of beam line penetration in the shield wall. Additional advantages of the circular shield wall tunnel are that it's simpler to construct, allows greater access to the insertion devices and the upstream in tunnel beam line components, as well as reducing the volume of concrete and therefore the cost of the shield wall.« less

Condenser for illuminating a ringfield camera with synchrotron emission light

DOEpatents

Sweatt, W.C.

1996-04-30

The present invention relates generally to the field of condensers for collecting light from a synchrotron radiation source and directing the light into a ringfield of a lithography camera. The present invention discloses a condenser comprising collecting, processing, and imaging optics. The collecting optics are comprised of concave and convex spherical mirrors that collect the light beams. The processing optics, which receive the light beams, are comprised of flat mirrors that converge and direct the light beams into a real entrance pupil of the camera in a symmetrical pattern. In the real entrance pupil are located flat mirrors, common to the beams emitted from the preceding mirrors, for generating substantially parallel light beams and for directing the beams toward the ringfield of a camera. Finally, the imaging optics are comprised of a spherical mirror, also common to the beams emitted from the preceding mirrors, images the real entrance pupil through the resistive mask and into the virtual entrance pupil of the camera. Thus, the condenser is comprised of a plurality of beams with four mirrors corresponding to a single beam plus two common mirrors. 9 figs.

Condenser for illuminating a ringfield camera with synchrotron emission light

DOEpatents

Sweatt, William C.

1996-01-01

The present invention relates generally to the field of condensers for collecting light from a synchrotron radiation source and directing the light into a ringfield of a lithography camera. The present invention discloses a condenser comprising collecting, processing, and imaging optics. The collecting optics are comprised of concave and convex spherical mirrors that collect the light beams. The processing optics, which receive the light beams, are comprised of flat mirrors that converge and direct the light beams into a real entrance pupil of the camera in a symmetrical pattern. In the real entrance pupil are located flat mirrors, common to the beams emitted from the preceding mirrors, for generating substantially parallel light beams and for directing the beams toward the ringfield of a camera. Finally, the imaging optics are comprised of a spherical mirror, also common to the beams emitted from the preceding mirrors, images the real entrance pupil through the resistive mask and into the virtual entrance pupil of the camera. Thus, the condenser is comprised of a plurality of beams with four mirrors corresponding to a single beam plus two common mirrors.

Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques.

PubMed

Terzano, Roberto; Santoro, Anna; Spagnuolo, Matteo; Vekemans, Bart; Medici, Luca; Janssens, Koen; Göttlicher, Jörg; Denecke, Melissa A; Mangold, Stefan; Ruggiero, Pacifico

2010-08-01

Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg(-1). Hg chemical forms were identified and quantified by sequential extractions and bulk- and micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as mu-XRF, mu-XRD and mu-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 microm. The main Hg-species found in the soil samples were metacinnabar (beta-HgS), cinnabar (alpha-HgS), corderoite (Hg(3)S(2)Cl(2)), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 microm. No interaction among Hg-species and soil components was observed. All the observed Hg-species originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution. Copyright 2010 Elsevier Ltd. All rights reserved.

A new high quality X-ray source for Cultural Heritage

NASA Astrophysics Data System (ADS)

Walter, Philippe; Variola, Alessandro; Zomer, Fabian; Jaquet, Marie; Loulergue, Alexandre

2009-09-01

Compton based photon sources have generated much interest since the rapid advance in laser and accelerator technologies has allowed envisaging their utilisation for ultra-compact radiation sources. These should provide X-ray short pulses with a relatively high average flux. Moreover, the univocal dependence between the scattered photon energy and its angle gives the possibility of obtaining a quasi-monochromatic beam with a simple diaphragm system. For the most ambitious projects the expected performance takes into account a rate of 10-10 photons/s, with an angular divergence of few mrad, an X-ray energy cut-off of few tens of keV and a bandwidth ΔE/E˜1-10%. Even if the integrated rate cannot compete with synchrotron radiation sources, the cost and the compactness of these Compton based machines make them attractive for a wide spectrum of applications. We explore here the interest of these systems for Cultural Heritage preservation. To cite this article: P. Walter et al., C. R. Physique 10 (2009).

High-spatial-resolution mapping of superhydrophobic cicada wing surface chemistry using infrared microspectroscopy and infrared imaging at two synchrotron beamlines.

PubMed

Tobin, Mark J; Puskar, Ljiljana; Hasan, Jafar; Webb, Hayden K; Hirschmugl, Carol J; Nasse, Michael J; Gervinskas, Gediminas; Juodkazis, Saulius; Watson, Gregory S; Watson, Jolanta A; Crawford, Russell J; Ivanova, Elena P

2013-05-01

The wings of some insects, such as cicadae, have been reported to possess a number of interesting and unusual qualities such as superhydrophobicity, anisotropic wetting and antibacterial properties. Here, the chemical composition of the wings of the Clanger cicada (Psaltoda claripennis) were characterized using infrared (IR) microspectroscopy. In addition, the data generated from two separate synchrotron IR facilities, the Australian Synchrotron Infrared Microspectroscopy beamline (AS-IRM) and the Synchrotron Radiation Center (SRC), University of Wisconsin-Madison, IRENI beamline, were analysed and compared. Characteristic peaks in the IR spectra of the wings were assigned primarily to aliphatic hydrocarbon and amide functionalities, which were considered to be an indication of the presence of waxy and proteinaceous components, respectively, in good agreement with the literature. Chemical distribution maps showed that, while the protein component was homogeneously distributed, a significant degree of heterogeneity was observed in the distribution of the waxy component, which may contribute to the self-cleaning and aerodynamic properties of the cicada wing. When comparing the data generated from the two beamlines, it was determined that the SRC IRENI beamline was capable of producing higher-spatial-resolution distribution images in a shorter time than was achievable at the AS-IRM beamline, but that spectral noise levels per pixel were considerably lower on the AS-IRM beamline, resulting in more favourable data where the detection of weak absorbances is required. The data generated by the two complementary synchrotron IR methods on the chemical composition of cicada wings will be immensely useful in understanding their unusual properties with a view to reproducing their characteristics in, for example, industry applications.

Light output measurements and computational models of microcolumnar CsI scintillators for x-ray imaging.

PubMed

Nillius, Peter; Klamra, Wlodek; Sibczynski, Pawel; Sharma, Diksha; Danielsson, Mats; Badano, Aldo

2015-02-01

The authors report on measurements of light output and spatial resolution of microcolumnar CsI:Tl scintillator detectors for x-ray imaging. In addition, the authors discuss the results of simulations aimed at analyzing the results of synchrotron and sealed-source exposures with respect to the contributions of light transport to the total light output. The authors measured light output from a 490-μm CsI:Tl scintillator screen using two setups. First, the authors used a photomultiplier tube (PMT) to measure the response of the scintillator to sealed-source exposures. Second, the authors performed imaging experiments with a 27-keV monoenergetic synchrotron beam and a slit to calculate the total signal generated in terms of optical photons per keV. The results of both methods are compared to simulations obtained with hybridmantis, a coupled x-ray, electron, and optical photon Monte Carlo transport package. The authors report line response (LR) and light output for a range of linear absorption coefficients and describe a model that fits at the same time the light output and the blur measurements. Comparing the experimental results with the simulations, the authors obtained an estimate of the absorption coefficient for the model that provides good agreement with the experimentally measured LR. Finally, the authors report light output simulation results and their dependence on scintillator thickness and reflectivity of the backing surface. The slit images from the synchrotron were analyzed to obtain a total light output of 48 keV -1 while measurements using the fast PMT instrument setup and sealed-sources reported a light output of 28 keV -1 . The authors attribute the difference in light output estimates between the two methods to the difference in time constants between the camera and PMT measurements. Simulation structures were designed to match the light output measured with the camera while providing good agreement with the measured LR resulting in a bulk absorption coefficient of 5 × 10 -5 μm -1 . The combination of experimental measurements for microcolumnar CsI:Tl scintillators using sealed-sources and synchrotron exposures with results obtained via simulation suggests that the time course of the emission might play a role in experimental estimates. The procedure yielded an experimentally derived linear absorption coefficient for microcolumnar Cs:Tl of 5 × 10 -5 μm -1 . To the author's knowledge, this is the first time this parameter has been validated against experimental observations. The measurements also offer insight into the relative role of optical transport on the effective optical yield of the scintillator with microcolumnar structure. © 2015 American Association of Physicists in Medicine.

Light output measurements and computational models of microcolumnar CsI scintillators for x-ray imaging.

PubMed

Nillius, Peter; Klamra, Wlodek; Sibczynski, Pawel; Sharma, Diksha; Danielsson, Mats; Badano, Aldo

2015-02-01

The authors report on measurements of light output and spatial resolution of microcolumnar CsI:Tl scintillator detectors for x-ray imaging. In addition, the authors discuss the results of simulations aimed at analyzing the results of synchrotron and sealed-source exposures with respect to the contributions of light transport to the total light output. The authors measured light output from a 490-μm CsI:Tl scintillator screen using two setups. First, the authors used a photomultiplier tube (PMT) to measure the response of the scintillator to sealed-source exposures. Second, the authors performed imaging experiments with a 27-keV monoenergetic synchrotron beam and a slit to calculate the total signal generated in terms of optical photons per keV. The results of both methods are compared to simulations obtained with hybridmantis, a coupled x-ray, electron, and optical photon Monte Carlo transport package. The authors report line response (LR) and light output for a range of linear absorption coefficients and describe a model that fits at the same time the light output and the blur measurements. Comparing the experimental results with the simulations, the authors obtained an estimate of the absorption coefficient for the model that provides good agreement with the experimentally measured LR. Finally, the authors report light output simulation results and their dependence on scintillator thickness and reflectivity of the backing surface. The slit images from the synchrotron were analyzed to obtain a total light output of 48 keV−1 while measurements using the fast PMT instrument setup and sealed-sources reported a light output of 28 keV−1. The authors attribute the difference in light output estimates between the two methods to the difference in time constants between the camera and PMT measurements. Simulation structures were designed to match the light output measured with the camera while providing good agreement with the measured LR resulting in a bulk absorption coefficient of 5 × 10−5μm−1. The combination of experimental measurements for microcolumnar CsI:Tl scintillators using sealed-sources and synchrotron exposures with results obtained via simulation suggests that the time course of the emission might play a role in experimental estimates. The procedure yielded an experimentally derived linear absorption coefficient for microcolumnar Cs:Tl of 5 × 10−5μm−1. To the author’s knowledge, this is the first time this parameter has been validated against experimental observations. The measurements also offer insight into the relative role of optical transport on the effective optical yield of the scintillator with microcolumnar structure.

X-Ray Data Booklet

Science.gov Websites

X-RAY DATA BOOKLET Center for X-ray Optics and Advanced Light Source Lawrence Berkeley National Laboratory Introduction X-Ray Properties of Elements Electron Binding Energies X-Ray Energy Emission Energies Table of X-Ray Properties Synchrotron Radiation Characteristics of Synchrotron Radiation History of X

Bicentennial Source Book, Level II, Grades 3-5.

ERIC Educational Resources Information Center

Orth, Nancy; And Others

This study activities source book is one of a series of four developed by the Carroll County Public School System, Maryland, for celebration of the Bicentennial. It is specifically designed to generate ideas integrating the Bicentennial celebration into various disciplines, classroom activities, and school-wide events at the third grade through…

Tests of monolithic active pixel sensors at national synchrotron light source

NASA Astrophysics Data System (ADS)

Deptuch, G.; Besson, A.; Carini, G. A.; Siddons, D. P.; Szelezniak, M.; Winter, M.

2007-01-01

The paper discusses basic characterization of Monolithic Active Pixel Sensors (MAPS) carried out at the X12A beam-line at National Synchrotron Light Source (NSLS), Upton, NY, USA. The tested device was a MIMOSA V (MV) chip, back-thinned down to the epitaxial layer. This 1M pixels device features a pixel size of 17×17 μm2 and was designed in a 0.6 μm CMOS process. The X-ray beam energies used range from 5 to 12 keV. Examples of direct X-ray imaging capabilities are presented.

Facilities for small-molecule crystallography at synchrotron sources.

PubMed

Barnett, Sarah A; Nowell, Harriott; Warren, Mark R; Wilcox, Andrian; Allan, David R

2016-01-01

Although macromolecular crystallography is a widely supported technique at synchrotron radiation facilities throughout the world, there are, in comparison, only very few beamlines dedicated to small-molecule crystallography. This limited provision is despite the increasing demand for beamtime from the chemical crystallography community and the ever greater overlap between systems that can be classed as either small macromolecules or large small molecules. In this article, a very brief overview of beamlines that support small-molecule single-crystal diffraction techniques will be given along with a more detailed description of beamline I19, a dedicated facility for small-molecule crystallography at Diamond Light Source.

Microscope using an x-ray tube and a bubble compound refractive lens

NASA Astrophysics Data System (ADS)

Piestrup, M. A.; Gary, C. K.; Park, H.; Harris, J. L.; Cremer, J. T.; Pantell, R. H.; Dudchik, Y. I.; Kolchevsky, N. N.; Komarov, F. F.

2005-03-01

We present x-ray images of grid meshes and biological material obtained using an unfiltered x-ray tube and a compound refractive lens composed of microbubbles embedded in epoxy inside a glass capillary. Images obtained using this apparatus are compared with those using a synchrotron source and the same lens. We find that the field of view is larger than that obtained using the synchrotron source, whereas the contrast and resolution are reduced. Geometrical distortion around the edges of the field of view is also reduced. The experiments demonstrate the usefulness of the apparatus in a modest laboratory setting.

High Resolution Far-Infrared Spectra of Thiophosgene with a Synchrotron Source: The ν2 and ν4 Bands Near 500 cm-1

NASA Astrophysics Data System (ADS)

McKellar, A. R. W.; Billinghurst, B. E.

2010-02-01

Thiophosgene (Cl2CS) is a favorite model system for studies of vibrational dynamics. But there are no previous rotationally-resolved infrared studies because the spectra are very congested due to its (relatively) large mass and multiple isotopic species. Here we report a detailed gas-phase study of the ν2 (˜504 cm-1) and ν4 (˜471 cm-1) fundamental bands, based on spectra obtained at the Canadian Light Source far-infrared beamline using synchrotron radiation and a Bruker IFS125 FT spectrometer.

Solid-state laser source of narrowband ultraviolet B light for skin disease care

NASA Astrophysics Data System (ADS)

Tarasov, Aleksandr A.; Chu, Hong

2013-03-01

We report about the development of all-solid-state laser source of narrowband UV-B light for medical applications. The device is based on a gain-switched Ti: Sapphire laser with volume Bragg grating, pumped at 532 nm and operating at 931.8 nm, followed by a third harmonic generator and a fiber optic beam homogenizer. The maximum available pulse energy exceeded 5 mJ at 310.6 nm, with a pulse repetition rates of 50 Hz. The output characteristics satisfy the medical requirements for psoriasis and vitiligo treatment. A new optical scheme for third harmonic generation enhancement at moderate levels of input intensities is proposed and investigated. As a result, 40% harmonic efficiency was obtained, when input pulse power was only 300 kW.

Isolation of Coherent Synchrotron Emission During Relativistic Laser Plasma Interactions

NASA Astrophysics Data System (ADS)

Dromey, B.; Rykovanov, S. G.; Lewis, C. L. S.; Zepf, M.

Coherent Synchrotron Emission (CSE) from relativistic laser plasmas (Pukhov et al., Plas Phys Control Fusion 52:124039, 2010; Dromey et al., Nat Phys 8:804-808, 2012; Dromey et al., New J Phys 15:015025, 2013) has recently been identified as a unique platform for the generation of coherent extreme ultraviolet (XUV) and X-Ray radiation with clear potential for bright attosecond pulse production. Exploiting this potential requires careful selection of interaction geometry, spectral wavelength range and target characteristics to allow the generation of high fidelity single attosecond pulses. In the laboratory the first step on this road is to study the individual mechanisms driving the emission of coherent extreme ultraviolet and X-Ray radiation during laser solid interactions in isolation. Here we show how interactions can be tailored to permit the unambiguous observation of coherent synchrotron emission (CSE) and the implications of this geometry for the resulting harmonic spectrum over the duration of the interaction.

EMITTING ELECTRONS AND SOURCE ACTIVITY IN MARKARIAN 501

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mankuzhiyil, Nijil; Ansoldi, Stefano; Persic, Massimo

2012-07-10

We study the variation of the broadband spectral energy distribution (SED) of the BL Lac object Mrk 501 as a function of source activity, from quiescent to flaring. Through {chi}{sup 2}-minimization we model eight simultaneous SED data sets with a one-zone synchrotron self-Compton (SSC) model, and examine how model parameters vary with source activity. The emerging variability pattern of Mrk 501 is complex, with the Compton component arising from {gamma}-e scatterings that sometimes are (mostly) Thomson and sometimes (mostly) extreme Klein-Nishina. This can be seen from the variation of the Compton to synchrotron peak distance according to source state. Themore » underlying electron spectra are faint/soft in quiescent states and bright/hard in flaring states. A comparison with Mrk 421 suggests that the typical values of the SSC parameters are different in the two sources: however, in both jets the energy density is particle-dominated in all states.« less

Beam measurement of the high frequency impedance sources with long bunches in the CERN Super Proton Synchrotron

NASA Astrophysics Data System (ADS)

Lasheen, A.; Argyropoulos, T.; Bohl, T.; Esteban Müller, J. F.; Timko, H.; Shaposhnikova, E.

2018-03-01

Microwave instability in the Super Proton Synchrotron (SPS) at CERN is one of the main limitations to reach the requirements for the High Luminosity-LHC project (increased beam intensity by a factor 2). To identify the impedance source responsible of the instability, beam measurements were carried out to probe the SPS impedance. The method presented in this paper relies on measurements of the unstable spectra of single bunches, injected in the SPS with the rf voltage switched off. The modulation of the bunch profile gives information about the main impedance sources driving microwave instability, and is compared to particle simulations using the SPS impedance model to identify the most important contributions. This allowed us to identify the vacuum flanges as the main impedance source for microwave instability in the SPS, and to evaluate possible missing impedance sources.

Translation of Atherosclerotic Plaque Phase-Contrast CT Imaging from Synchrotron Radiation to a Conventional Lab-Based X-Ray Source

PubMed Central

Saam, Tobias; Herzen, Julia; Hetterich, Holger; Fill, Sandra; Willner, Marian; Stockmar, Marco; Achterhold, Klaus; Zanette, Irene; Weitkamp, Timm; Schüller, Ulrich; Auweter, Sigrid; Adam-Neumair, Silvia; Nikolaou, Konstantin; Reiser, Maximilian F.; Pfeiffer, Franz; Bamberg, Fabian

2013-01-01

Objectives Phase-contrast imaging is a novel X-ray based technique that provides enhanced soft tissue contrast. The aim of this study was to evaluate the feasibility of visualizing human carotid arteries by grating-based phase-contrast tomography (PC-CT) at two different experimental set-ups: (i) applying synchrotron radiation and (ii) using a conventional X-ray tube. Materials and Methods Five ex-vivo carotid artery specimens were examined with PC-CT either at the European Synchrotron Radiation Facility using a monochromatic X-ray beam (2 specimens; 23 keV; pixel size 5.4 µm), or at a laboratory set-up on a conventional X-ray tube (3 specimens; 35-40 kVp; 70 mA; pixel size 100 µm). Tomographic images were reconstructed and compared to histopathology. Two independent readers determined vessel dimensions and one reader determined signal-to-noise ratios (SNR) between PC-CT and absorption images. Results In total, 51 sections were included in the analysis. Images from both set-ups provided sufficient contrast to differentiate individual vessel layers. All PCI-based measurements strongly predicted but significantly overestimated lumen, intima and vessel wall area for both the synchrotron and the laboratory-based measurements as compared with histology (all p<0.001 with slope >0.53 per mm2, 95%-CI: 0.35 to 0.70). Although synchrotron-based images were characterized by higher SNRs than laboratory-based images; both PC-CT set-ups had superior SNRs compared to corresponding conventional absorption-based images (p<0.001). Inter-reader reproducibility was excellent (ICCs >0.98 and >0.84 for synchrotron and for laboratory-based measurements; respectively). Conclusion Experimental PC-CT of carotid specimens is feasible with both synchrotron and conventional X-ray sources, producing high-resolution images suitable for vessel characterization and atherosclerosis research. PMID:24039969

A compact, coherent light source system architecture

NASA Astrophysics Data System (ADS)

Biedron, S. G.; Dattoli, G.; DiPalma, E.; Einstein, J.; Milton, S. V.; Petrillo, V.; Rau, J. V.; Sabia, E.; Spassovsky, I. P.; van der Slot, P. J. M.

2016-09-01

Our team has been examining several architectures for short-wavelength, coherent light sources. We are presently exploring the use and role of advanced, high-peak power lasers for both accelerating the electrons and generating a compact light source with the same laser. Our overall goal is to devise light sources that are more accessible by industry and in smaller laboratory settings. Although we cannot and do not want to compete directly with sources such as third-generation light sources or that of national-laboratory-based free-electron lasers, we have several interesting schemes that could bring useful and more coherent, short-wavelength light source to more researchers. Here, we present and discuss several results of recent simulations and our future steps for such dissemination.

Beam dynamics and expected performance of Sweden's new storage-ring light source: MAX IV

NASA Astrophysics Data System (ADS)

Leemann, S. C.; Andersson, Å.; Eriksson, M.; Lindgren, L.-J.; Wallén, E.; Bengtsson, J.; Streun, A.

2009-12-01

MAX IV will be Sweden’s next-generation high-performance synchrotron radiation source. The project has recently been granted funding and construction is scheduled to begin in 2010. User operation for a broad and international user community should commence in 2015. The facility is comprised of two storage rings optimized for different wavelength ranges, a linac-based short-pulse facility and a free-electron laser for the production of coherent radiation. The main radiation source of MAX IV will be a 528 m ultralow emittance storage ring operated at 3 GeV for the generation of high-brightness hard x rays. This storage ring was designed to meet the requirements of state-of-the-art insertion devices which will be installed in nineteen 5 m long dispersion-free straight sections. The storage ring is based on a novel multibend achromat design delivering an unprecedented horizontal bare lattice emittance of 0.33 nm rad and a vertical emittance below the 8 pm rad diffraction limit for 1 Å radiation. In this paper we present the beam dynamics considerations behind this storage-ring design and detail its expected unique performance.

Investigation on the absolute and relative photoionization cross sections of 3 potential propargylic fuels.

PubMed

Winfough, Matthew; Meloni, Giovanni

2017-12-01

Absolute photoionization cross sections for 2 potential propargylic fuels (propargylamine and dipropargyl ether) along with the partial ionization cross sections for their dissociative fragments are measured and presented for the first time via synchrotron photoionization mass spectrometry. The experimental setup consists of a multiplexed orthogonal time-of-flight mass spectrometer and is located at the Advanced Light Source facility of the Lawrence Berkeley National Laboratory in Berkeley, California. Data for a third propargylic compound (propargyl alcohol) were taken; however, because of its low signal, due to its weakly bound cation, only the dissociative ionization fragment from the H-loss channel is observed and presented. Suggested pathways leading to formation of dissociative photoionization fragments along with CBS-QB3 calculated adiabatic ionization energies and appearance energies for the dissociative fragments are also presented. Copyright © 2017 John Wiley & Sons, Ltd.

Operation of the Australian Store.Synchrotron for macromolecular crystallography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meyer, Grischa R.; Aragão, David; Mudie, Nathan J.

2014-10-01

The Store.Synchrotron service, a fully functional, cloud computing-based solution to raw X-ray data archiving and dissemination at the Australian Synchrotron, is described. The Store.Synchrotron service, a fully functional, cloud computing-based solution to raw X-ray data archiving and dissemination at the Australian Synchrotron, is described. The service automatically receives and archives raw diffraction data, related metadata and preliminary results of automated data-processing workflows. Data are able to be shared with collaborators and opened to the public. In the nine months since its deployment in August 2013, the service has handled over 22.4 TB of raw data (∼1.7 million diffraction images). Severalmore » real examples from the Australian crystallographic community are described that illustrate the advantages of the approach, which include real-time online data access and fully redundant, secure storage. Discoveries in biological sciences increasingly require multidisciplinary approaches. With this in mind, Store.Synchrotron has been developed as a component within a greater service that can combine data from other instruments at the Australian Synchrotron, as well as instruments at the Australian neutron source ANSTO. It is therefore envisaged that this will serve as a model implementation of raw data archiving and dissemination within the structural biology research community.« less

Recent progress in X-ray optics at the ESRF

NASA Astrophysics Data System (ADS)

Freund, A.

2003-03-01

It is the task of x-ray optics to adapt the raw beam generated by modern sources such as synchrotron storage rings to a great variety of experimental requirements in terms of intensity, spot size, polarization and other parameters. The very high quality of synchrotron radiation (source size of a few microns and beam divergence of a few micro-radians) and the extreme x-ray flux (power of several hundred Watts in a few square mm) make this task quite difficult. In particular the heat load aspect is very important in the conditioning process of the brute x-ray power. Cryogenically cooled silicon crystals and water-cooled diamond crystals can presently fulfil this task, but limits will soon be reached and new schemes and materials must be envisioned. A major tendency of instrument improvement has a ways been to concentrate more photons into a smaller spot utilizing a whole variety of focusing devices such as Fresnel zone plates, refractive lenses and Systems based on bent surfaces, for example Kirkpatrick-Baez Systems. Apart from the resistance of the sample, the ultimate limits are determined by the source size and strength on one side, by materials properties, cooling, mounting and bending schemes on the other side, and fundamentally by the diffraction process. There is also the important aspect of coherence that can be both a nuisance and a blessing for the experiments, in particular for imaging techniques. Its conservation puts additional constraints on the quality of the optical elements. A review of recent progress in this field is given.

Simulations of X-ray diffraction of shock-compressed single-crystal tantalum with synchrotron undulator sources.

PubMed

Tang, M X; Zhang, Y Y; E, J C; Luo, S N

2018-05-01

Polychromatic synchrotron undulator X-ray sources are useful for ultrafast single-crystal diffraction under shock compression. Here, simulations of X-ray diffraction of shock-compressed single-crystal tantalum with realistic undulator sources are reported, based on large-scale molecular dynamics simulations. Purely elastic deformation, elastic-plastic two-wave structure, and severe plastic deformation under different impact velocities are explored, as well as an edge release case. Transmission-mode diffraction simulations consider crystallographic orientation, loading direction, incident beam direction, X-ray spectrum bandwidth and realistic detector size. Diffraction patterns and reciprocal space nodes are obtained from atomic configurations for different loading (elastic and plastic) and detection conditions, and interpretation of the diffraction patterns is discussed.

Neutron and Synchrotron Radiation Studies for Designer Materials, Sustainable Energy and Healthy Lives

NASA Astrophysics Data System (ADS)

Gibson, J. Murray

2009-05-01

Probably the most prolific use of large accelerators today is in the creation of bright beams of x-ray photons or neutrons. The number of scientific users of such sources in the US alone is approaching 10,000. I will describe the some of the major applications of synchrotron and neutron radiation and their impact on society. If you have AIDS, need a better IPOD or a more efficient car, or want to clean up a superfund site, you are benefitting from these accelerators. The design of new materials is becoming more and more dependent on structural information from these sources. I will identify the trends in applications which are demanding new sources with greater capabilities.

Simulations of X-ray diffraction of shock-compressed single-crystal tantalum with synchrotron undulator sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, M. X.; Zhang, Y. Y.; E, J. C.

Polychromatic synchrotron undulator X-ray sources are useful for ultrafast single-crystal diffraction under shock compression. Here, simulations of X-ray diffraction of shock-compressed single-crystal tantalum with realistic undulator sources are reported, based on large-scale molecular dynamics simulations. Purely elastic deformation, elastic–plastic two-wave structure, and severe plastic deformation under different impact velocities are explored, as well as an edge release case. Transmission-mode diffraction simulations consider crystallographic orientation, loading direction, incident beam direction, X-ray spectrum bandwidth and realistic detector size. Diffraction patterns and reciprocal space nodes are obtained from atomic configurations for different loading (elastic and plastic) and detection conditions, and interpretation of themore » diffraction patterns is discussed.« less

Initial Experience of the Application of Automated Tube Potential Selection Technique in High-pitch Dual-source CT Angiography of Whole Aorta Using Third-generation Dual-source CT Scanner.

PubMed

Kong, Lingyan; Liang, Jixiang; Xue, Huadan; Wang, Yining; Wang, Yun; Jin, Zhengyu; Zhang, Daming; Chen, Jin

2017-02-20

Objective To evaluate the application of automated tube potential selection technique in high-pitch dual-source CT aortic angiography on a third-generation dual-source CT scanner. Methods Whole aorta angiography were indiated in 59 patients,who were divided into 2 groups using a simple random method:in group 1 there were 31 patients who underwent the examination with automated tube potential selection using a vascular setting with a preferred image quality of 288 mA/100 kV;in group 2 there were 28 patients who underwent the examination with a tube voltage of 100 kV and automated tube current modulation using a reference tube current of 288 mA. Both groups were scanned on a third generation dual-source CT device operated in dual-source high-pitch ECG-gating mode with a pitch of 3.0,collimation of 2×192×0.6 mm,and a rotation time of 0.25 s. Iterative reconstruction algorithm was used. For group 1,the volume and flow of contrast medium and chasing saline were adapted to the tube voltage. For group 2,a contrast material bolus of 45 ml with a flow of 4.5 ml/s followed by a 50 ml saline chaser at 5 ml/s was used. CTA scan was automatically started using a bolus tracking technique at the level of the original part of aorta after a trigger threshold of 100 HU was reached. The start delay was set to 6 s in both groups. Effective dose (ED),signal to noise ratio (SNR),contrast to noise ratio (CNR),and subjective diagnostic quality of both groups were evaluated. Results The mean ED were 21.3% lower (t=-3.099,P=0.000) in group 1 [(2.48±0.80) mSv] than in group 2 [(3.15±0.86) mSv]. Two groups showed no significant difference in attenuation,SD,SNR,or CNR at all evaluational parts of aorta (ascending aorta,aortic arch,diaphragmatic aorta,or iliac bifurcation)(all P>0.05). There was no significant difference in subjective diagnostic quality values of two groups [(1.41±0.50) scores vs. (1.39±0.50) scores;W=828.5,P=0.837]. Conclusion Compared with automated tube current modulation,the automated tube potential selection technique in aorta CT angiography on a third-generation dual-source CT can dramatically reduce radiation dose without affecting image quality.

Three-dimensional monochromatic x-ray CT

NASA Astrophysics Data System (ADS)

Saito, Tsuneo; Kudo, Hiroyuki; Takeda, Tohoru; Itai, Yuji; Tokumori, Kenji; Toyofuku, Fukai; Hyodo, Kazuyuki; Ando, Masami; Nishimura, Ktsuyuki; Uyama, Chikao

1995-08-01

In this paper, we describe a 3D computed tomography (3D CT) using monochromatic x-rays generated by synchrotron radiation, which performs a direct reconstruction of 3D volume image of an object from its cone-beam projections. For the develpment of 3D CT, scanning orbit of x-ray source to obtain complete 3D information about an object and corresponding 3D image reconstruction algorithm are considered. Computer simulation studies demonstrate the validities of proposed scanning method and reconstruction algorithm. A prototype experimental system of 3D CT was constructed. Basic phantom examinations and specific material CT image by energy subtraction obtained in this experimental system are shown.

Probing Combustion Chemistry in a Miniature Shock Tube with Synchrotron VUV Photo Ionization Mass Spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lynch, Patrick T.; Troy, Tyler P.; Ahmed, Musahid

2015-01-29

Tunable synchrotron-sourced photoionization time-of-flight mass spectrometry (PI-TOF-MS) is an important technique in combustion chemistry, complementing lab-scale electron impact and laser photoionization studies for a wide variety of reactors, typically at low pressure. For high-temperature and high-pressure chemical kinetics studies, the shock tube is the reactor of choice. Extending the benefits of shock tube/TOF-MS research to include synchrotron sourced PI-TOF-MS required a radical reconception of the shock tube. An automated, miniature, high-repetition-rate shock tube was developed and can be used to study high-pressure reactive systems (T > 600 K, P < 100 bar) behind reflected shock waves. In this paper, wemore » present results of a PI-TOF-MS study at the Advanced Light Source at Lawrence Berkeley National Laboratory. Dimethyl ether pyrolysis (2% CH3OCH3/Ar) was observed behind the reflected shock (1400 < T-5 < 1700 K, 3 < P-5 < 16 bar) with ionization energies between 10 and 13 eV. Individual experiments have extremely low signal levels. However, product species and radical intermediates are well-resolved when averaging over hundreds of shots, which is ordinarily impractical in conventional shock tube studies. The signal levels attained and data throughput rates with this technique are comparable to those with other synchrotron-based PI-TOF-MS reactors, and it is anticipated that this high pressure technique will greatly complement those lower pressure techniques.« less

Reference dosimetry at the Australian Synchrotron's imaging and medical beamline using free-air ionization chamber measurements and theoretical predictions of air kerma rate and half value layer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crosbie, Jeffrey C.; Rogers, Peter A. W.; Stevenson, Andrew W.

2013-06-15

Purpose: Novel, preclinical radiotherapy modalities are being developed at synchrotrons around the world, most notably stereotactic synchrotron radiation therapy and microbeam radiotherapy at the European Synchrotron Radiation Facility in Grenoble, France. The imaging and medical beamline (IMBL) at the Australian Synchrotron has recently become available for preclinical radiotherapy and imaging research with clinical trials, a distinct possibility in the coming years. The aim of this present study was to accurately characterize the synchrotron-generated x-ray beam for the purposes of air kerma-based absolute dosimetry. Methods: The authors used a theoretical model of the energy spectrum from the wiggler source and validatedmore » this model by comparing the transmission through copper absorbers (0.1-3.0 mm) against real measurements conducted at the beamline. The authors used a low energy free air ionization chamber (LEFAC) from the Australian Radiation Protection and Nuclear Safety Agency and a commercially available free air chamber (ADC-105) for the measurements. The dimensions of these two chambers are different from one another requiring careful consideration of correction factors. Results: Measured and calculated half value layer (HVL) and air kerma rates differed by less than 3% for the LEFAC when the ion chamber readings were corrected for electron energy loss and ion recombination. The agreement between measured and predicted air kerma rates was less satisfactory for the ADC-105 chamber, however. The LEFAC and ADC measurements produced a first half value layer of 0.405 {+-} 0.015 and 0.412 {+-} 0.016 mm Cu, respectively, compared to the theoretical prediction of 0.427 {+-} 0.012 mm Cu. The theoretical model based upon a spectrum calculator derived a mean beam energy of 61.4 keV with a first half value layer of approximately 30 mm in water. Conclusions: The authors showed in this study their ability to verify the predicted air kerma rate and x-ray attenuation curve on the IMBL using a simple experimental method, namely, HVL measurements. The HVL measurements strongly supports the x-ray beam spectrum, which in turn has a profound effect on x-ray dosimetry.« less

Galactic synchrotron radiation from radio to microwaves, and its relation to cosmic-ray propagation models: past, present and future

NASA Astrophysics Data System (ADS)

Orlando, Elena

2016-04-01

Galactic synchrotron radiation observed from radio to microwaves is produced by cosmic-ray (CR) electrons propagating in magnetic fields (B-fields). The low-frequency foreground component separated maps by WMAP and Planck depend on the assumed synchrotron spectrum. The synchrotron spectrum varies for different line of sights as a result of changes on the CR spectrum due to propagation effects and source distributions. Our present knowledge of the CR spectrum at different locations in the Galaxy is not sufficient to distinguish various possibilities in the modeling. As a consequence uncertainties on synchrotron emission models complicate the foreground component separation analysis with Planck and future microwave telescopes. Hence, any advancement in synchrotron modeling is important for separating the different foreground components.The first step towards a more comprehensive understanding of degeneracy and correlation among the synchrotron model parameters is outlined in our Strong et al. 2011 and Orlando et al. 2013 papers. In the latter the conclusion was that CR spectrum, propagation models, B-fields, and foreground component separation analysis need to be studied simultaneously in order to properly obtain and interpret the synchrotron foreground. Indeed for the officially released Planck maps, we use only the best spectral model from our above paper for the component separation analysis.Here we present a collections of our latest results on synchrotron, CRs and B-fields in the context of CR propagation, showing also our recent work on B-fields within the Planck Collaboration. We underline also the importance of using the constraints on CRs that we obtain from gamma ray observations. Methods and perspectives for further studies on the synchrotron foreground will be addressed.

Coherent synchrotron radiation for laminar flows

NASA Astrophysics Data System (ADS)

Schmekel, Bjoern S.; Lovelace, Richard V. E.

2006-11-01

We investigate the effect of shear in the flow of charged particle equilibria that are unstable to the coherent synchrotron radiation (CSR) instability. Shear may act to quench this instability because it acts to limit the size of the region with a fixed phase relation between emitters. The results are important for the understanding of astrophysical sources of coherent radiation where shear in the flow is likely.

Contrast agent choice for intravenous coronary angiography

NASA Astrophysics Data System (ADS)

Zeman, H. D.; Siddons, D. P.

1990-05-01

The screening of the general population for coronary artery disease would be practical if a method existed for visualizing the extent of occlusion after an intravenous injection of contrast agent. Measurements performed with monochromatic synchrotron radiation X-rays and an iodine-containing contrast agent at the Stanford Synchrotron Radiation Laboratory have shown that such an intravenous angiography procedure would be possible with an adequately intense monochromatic X-ray source. Because of the size and cost of synchrotron radiation facilities it would be desirable to make the most efficient use of the intensity available, while reducing as much as possible the radiation dose experienced by the patient. By choosing contrast agents containing elements with a higher atomic number than iodine, it is possible to both improve the image quality and reduce the patient radiation dose, while using the same synchrotron radiation source. By using Si monochromator crystals with a small mosaic spread, it is possible to increase the X-ray flux available for imaging by over an order of magnitude, without any changes in the storage ring or wiggler magnet. The most critical imaging task for intravenous coronary angiography utilizing synchrotron radiation X-rays is visualizing a coronary artery through the left ventricle or aorta which also contain contrast agent. Calculations have been made of the signal to noise ratio expected for this imaging task for various contrast agents with atomic numbers between that of iodine and bismuth. The X-ray energy spectrum of the X-17 superconduction wiggler beam line at the National Synchrotron Light Source at Brookhaven National Laboratory has been used for these calculations. Both perfect Si crystals and Si crystals with a small mosaic spread are considered as monochromators. Contrast agents containing Gd or Yb seem to have about the optimal calculated signal to noise ratio. Gd-DTPA is already approved for use as a contrast agent for magnetic resonance imaging. Experiments have already been performed with Yb-DTPA in animals, and it appears to have a lower toxicity than that of Gd-DTPA. Reported animal experiments with Gd-DOTA contrast agent show no toxicity at all.

Direct observation of Young’s double-slit interferences in vibrationally resolved photoionization of diatomic molecules

PubMed Central

Canton, Sophie E.; Plésiat, Etienne; Bozek, John D.; Rude, Bruce S.; Decleva, Piero; Martín, Fernando

2011-01-01

Vibrationally resolved valence-shell photoionization spectra of H2, N2 and CO have been measured in the photon energy range 20–300 eV using third-generation synchrotron radiation. Young’s double-slit interferences lead to oscillations in the corresponding vibrational ratios, showing that the molecules behave as two-center electron-wave emitters and that the associated interferences leave their trace in the angle-integrated photoionization cross section. In contrast to previous work, the oscillations are directly observable in the experiment, thereby removing any possible ambiguity related to the introduction of external parameters or fitting functions. A straightforward extension of an original idea proposed by Cohen and Fano [Cohen HD, Fano U (1966) Phys Rev 150:30] confirms this interpretation and shows that it is also valid for diatomic heteronuclear molecules. Results of accurate theoretical calculations are in excellent agreement with the experimental findings.

New theoretical results in synchrotron radiation

NASA Astrophysics Data System (ADS)

Bagrov, V. G.; Gitman, D. M.; Tlyachev, V. B.; Jarovoi, A. T.

2005-11-01

One of the remarkable features of the relativistic electron synchrotron radiation is its concentration in small angle Δ ≈ 1/γ (here γ-relativistic factor: γ = E/mc2, E energy, m electron rest mass, c light velocity) near rotation orbit plane [V.G. Bagrov, V.A. Bordovitsyn, V.G. Bulenok, V. Ya. Epp, Kinematical projection of pulsar synchrotron radiation profiles, in: Proceedings of IV ISTC Scientific Advisory Commitee Seminar on Basic Science in ISTC Aktivities, Akademgorodok, Novosibirsk, April 23 27, 2001, p. 293 300]. This theoretically predicted and experimentally confirmed feature is peculiar to total (spectrum summarized) radiating intensity. This angular distribution property has been supposed to be (at least qualitatively) conserved and for separate spectrum synchrotron radiation components. In the work of V.G. Bagrov, V.A. Bordovitsyn, V. Ch. Zhukovskii, Development of the theory of synchrotron radiation and related processes. Synchrotron source of JINR: the perspective of research, in: The Materials of the Second International Work Conference, Dubna, April 2 6, 2001, pp. 15 30 and in Angular dependence of synchrotron radiation intensity. http://lanl.arXiv.org/abs/physics/0209097, it is shown that the angular distribution of separate synchrotron radiation spectrum components demonstrates directly inverse tendency the angular distribution deconcentration relatively the orbit plane takes place with electron energy growth. The present work is devoted to detailed investigation of this situation. For exact quantitative estimation of angular concentration degree of synchrotron radiation the definition of radiation effective angle and deviation angle is proposed. For different polarization components of radiation the dependence of introduced characteristics was investigated as a functions of electron energy and number of spectrum component.

Emittance preservation during bunch compression with a magnetized beam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stratakis, Diktys

2015-09-02

The deleterious effects of coherent synchrotron radiation (CSR) on the phase-space and energy spread of high-energy beams in accelerator light sources can significantly constrain the machine design and performance. In this paper, we present a simple method to preserve the beam emittance by means of using magnetized beams that exhibit a large aspect ratio on their transverse dimensions. The concept is based on combining a finite solenoid field where the beam is generated together with a special optics adapter. Numerical simulations of this new type of beam source show that the induced phase-space density growth can be notably suppressed tomore » less than 1% for any bunch charge. This work elucidates the key parameters that are needed for emittance preservation, such as the required field and aspect ratio for a given bunch charge.« less

X-ray flares from runaway pair production in active galactic nuclei

NASA Technical Reports Server (NTRS)

Kirk, J. G.; Mastichiadis, A.

1992-01-01

The hard X-ray spectrum of AGNs is nonthermal, probably arising from an electron-positron pair cascade, with some emission reflected off relatively cold matter. There has been interest in models on which protons are accelerated and create relativistic electrons on interaction with a local radiation field. It is shown here that a sufficient column density of protons can lead to runaway pair production: photons generated by the relativistic pairs are the targets for the protons to produce more pairs. This can produce X-ray fluxes with the characteristics observed in AGN. The model predicts the maximum ratio of luminosity to source size as well as their spectrum in the early phases. The same mechanism may also be able to create the knots of synchrotron-radiating pair plasma seen in sources such as 3C273.

High duty factor plasma generator for CERN's Superconducting Proton Linac.

PubMed

Lettry, J; Kronberger, M; Scrivens, R; Chaudet, E; Faircloth, D; Favre, G; Geisser, J-M; Küchler, D; Mathot, S; Midttun, O; Paoluzzi, M; Schmitzer, C; Steyaert, D

2010-02-01

CERN's Linac4 is a 160 MeV linear accelerator currently under construction. It will inject negatively charged hydrogen ions into CERN's PS-Booster. Its ion source is a noncesiated rf driven H(-) volume source directly inspired from the one of DESY and is aimed to deliver pulses of 80 mA of H(-) during 0.4 ms at a 2 Hz repetition rate. The Superconducting Proton Linac (SPL) project is part of the luminosity upgrade of the Large Hadron Collider. It consists of an extension of Linac4 up to 5 GeV and is foreseen to deliver protons to a future 50 GeV synchrotron (PS2). For the SPL high power option (HP-SPL), the ion source would deliver pulses of 80 mA of H(-) during 1.2 ms and operate at a 50 Hz repetition rate. This significant upgrade motivates the design of the new water cooled plasma generator presented in this paper. Its engineering is based on the results of a finite element thermal study of the Linac4 H(-) plasma generator that identified critical components and thermal barriers. A cooling system is proposed which achieves the required heat dissipation and maintains the original functionality. Materials with higher thermal conductivity are selected and, wherever possible, thermal barriers resulting from low pressure contacts are removed by brazing metals on insulators. The AlN plasma chamber cooling circuit is inspired from the approach chosen for the cesiated high duty factor rf H(-) source operating at SNS.

Characterizing radio continuum sources in a sample of Hi-GAL massive cores

NASA Astrophysics Data System (ADS)

Armstrong, Jason

In 2012 and 2013, Olmi and collaborators conducted a survey for 6.7GHz methanol masers with the Arecibo Telescope toward far infrared sources selected from the Hi-GAL catalog of massive cores. They reported a number of sources with weak 6.7GHz methanol masers, possibly indicating regions in early stages of star formation. Follow-up observations were conducted with the Karl G. Jansky Very Large Array (VLA) in New Mexico to characterize the sources. This thesis presents the results of radio continuum observations of nine of the Arecibo regions. A total of 33 radio continuum sources were detected. The nature of the radio continuum sources was analyzed based on their spectral indices. Most of the sources have negative spectral indices, which is indicative of synchrotron radiation. Many of the synchrotron sources are associated with a supernova remnant in our Galaxy, while the rest are likely background radio galaxies and quasars. Evidence for thermal bremsstrahlung radiation was found toward six sources associated with the Arecibo regions, which is consistent with the interpretation of gas ionized by young high-mass stellar objects.

Synchrotron FTIR Imaging For The Identification Of Cell Types Within Human Tissues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walsh, Michael J.; Pounder, F. Nell; Nasse, Michael J.

2010-02-03

The use of synchrotron Fourier Transform Infrared spectroscopy (S-FTIR) has been shown to be a very promising tool for biomedical research. S-FTIR spectroscopy allows for the fast acquisition of infrared (IR) spectra at a spatial resolution approaching the IR diffraction limit. The development of the Infrared Environmental Imaging (IRENI) beamline at the Synchrotron Radiation Center (SRC) at the University of Wisconsin-Madison has allowed for diffraction limited imaging measurements of cells in human prostate and breast tissues. This has allowed for the identification of cell types within tissues that would otherwise not have been resolvable using conventional FTIR sources.

Observation of superradiant synchrotron radiation in the terahertz region

NASA Astrophysics Data System (ADS)

Billinghurst, B. E.; Bergstrom, J. C.; Dallin, L.; de Jong, M.; May, T. E.; Vogt, J. M.; Wurtz, W. A.

2013-06-01

We report the first high-resolution measurement of superradiance, using coherent synchrotron radiation in the terahertz region from the Canadian Light Source synchrotron and a Michelson interferometer with a nominal frequency resolution of 0.00096cm-1. Superradiance arises when a high degree of phase coherence exists between the radiation fields of the individual electron bunches, and manifests itself as a series of narrow spectral peaks at harmonics of the bunch frequency. We observe an enhancement factor of 16 at the spectral peaks, limited by the interferometer resolution. The spectral distribution and relative amplitudes of the superradiant peaks are modified by altering the pattern of bunches along the bunch train.

Acoustic methods for high-throughput protein crystal mounting at next-generation macromolecular crystallographic beamlines.

PubMed

Roessler, Christian G; Kuczewski, Anthony; Stearns, Richard; Ellson, Richard; Olechno, Joseph; Orville, Allen M; Allaire, Marc; Soares, Alexei S; Héroux, Annie

2013-09-01

To take full advantage of advanced data collection techniques and high beam flux at next-generation macromolecular crystallography beamlines, rapid and reliable methods will be needed to mount and align many samples per second. One approach is to use an acoustic ejector to eject crystal-containing droplets onto a solid X-ray transparent surface, which can then be positioned and rotated for data collection. Proof-of-concept experiments were conducted at the National Synchrotron Light Source on thermolysin crystals acoustically ejected onto a polyimide `conveyor belt'. Small wedges of data were collected on each crystal, and a complete dataset was assembled from a well diffracting subset of these crystals. Future developments and implementation will focus on achieving ejection and translation of single droplets at a rate of over one hundred per second.

Acoustic methods for high-throughput protein crystal mounting at next-generation macromolecular crystallographic beamlines

PubMed Central

Roessler, Christian G.; Kuczewski, Anthony; Stearns, Richard; Ellson, Richard; Olechno, Joseph; Orville, Allen M.; Allaire, Marc; Soares, Alexei S.; Héroux, Annie

2013-01-01

To take full advantage of advanced data collection techniques and high beam flux at next-generation macromolecular crystallography beamlines, rapid and reliable methods will be needed to mount and align many samples per second. One approach is to use an acoustic ejector to eject crystal-containing droplets onto a solid X-ray transparent surface, which can then be positioned and rotated for data collection. Proof-of-concept experiments were conducted at the National Synchrotron Light Source on thermolysin crystals acoustically ejected onto a polyimide ‘conveyor belt’. Small wedges of data were collected on each crystal, and a complete dataset was assembled from a well diffracting subset of these crystals. Future developments and implementation will focus on achieving ejection and translation of single droplets at a rate of over one hundred per second. PMID:23955046

Integration and Beyond

PubMed Central

Stead, William W.; Miller, Randolph A.; Musen, Mark A.; Hersh, William R.

2000-01-01

The vision of integrating information—from a variety of sources, into the way people work, to improve decisions and process—is one of the cornerstones of biomedical informatics. Thoughts on how this vision might be realized have evolved as improvements in information and communication technologies, together with discoveries in biomedical informatics, and have changed the art of the possible. This review identified three distinct generations of “integration” projects. First-generation projects create a database and use it for multiple purposes. Second-generation projects integrate by bringing information from various sources together through enterprise information architecture. Third-generation projects inter-relate disparate but accessible information sources to provide the appearance of integration. The review suggests that the ideas developed in the earlier generations have not been supplanted by ideas from subsequent generations. Instead, the ideas represent a continuum of progress along the three dimensions of workflow, structure, and extraction. PMID:10730596

Immigrants' Cultural Identities as Sources of Civic Engagement

ERIC Educational Resources Information Center

Jensen, Lene Arnett

2008-01-01

Immigrant parents (first generation) and adolescents (second generation) from El Salvador and India (N = 80) took part in interviews on civic engagement. The immigrants were almost unanimous in regarding civic engagement as important. They also were engaged themselves, more so at the community than the political level. One third of immigrants were…

Molecular Beam Mass Spectrometry With Tunable Vacuum Ultraviolet (VUV) Synchrotron Radiation

PubMed Central

Golan, Amir; Ahmed, Musahid

2012-01-01

Tunable soft ionization coupled to mass spectroscopy is a powerful method to investigate isolated molecules, complexes and clusters and their spectroscopy and dynamics1-4. Fundamental studies of photoionization processes of biomolecules provide information about the electronic structure of these systems. Furthermore determinations of ionization energies and other properties of biomolecules in the gas phase are not trivial, and these experiments provide a platform to generate these data. We have developed a thermal vaporization technique coupled with supersonic molecular beams that provides a gentle way to transport these species into the gas phase. Judicious combination of source gas and temperature allows for formation of dimers and higher clusters of the DNA bases. The focus of this particular work is on the effects of non-covalent interactions, i.e., hydrogen bonding, stacking, and electrostatic interactions, on the ionization energies and proton transfer of individual biomolecules, their complexes and upon micro-hydration by water1, 5-9. We have performed experimental and theoretical characterization of the photoionization dynamics of gas-phase uracil and 1,3-dimethyluracil dimers using molecular beams coupled with synchrotron radiation at the Chemical Dynamics Beamline10 located at the Advanced Light Source and the experimental details are visualized here. This allowed us to observe the proton transfer in 1,3-dimethyluracil dimers, a system with pi stacking geometry and with no hydrogen bonds1. Molecular beams provide a very convenient and efficient way to isolate the sample of interest from environmental perturbations which in return allows accurate comparison with electronic structure calculations11, 12. By tuning the photon energy from the synchrotron, a photoionization efficiency (PIE) curve can be plotted which informs us about the cationic electronic states. These values can then be compared to theoretical models and calculations and in turn, explain in detail the electronic structure and dynamics of the investigated species 1, 3. PMID:23149375

Fact sheet : efforts on climate change

DOT National Transportation Integrated Search

2008-03-01

The Oregon Department of Transportation recognizes that the transportation sector in : Oregon generates significant greenhouse gases. In fact, transportation sources are responsible for over a third of emissions in the state roughly the same shar...

Magnetic fields in Supernova Remnants and Pulsar-Wind Nebulae: Deductions from X-ray Observations

NASA Astrophysics Data System (ADS)

Reynolds, S. P.

2016-06-01

Magnetic field strengths B in synchrotron sources are notoriously difficult to measure. Simple arguments such as equipartition of energy can give values for which the total energy is a minimum, but there is no guarantee that Nature obeys it, or even if so, what particle population (just electrons? electrons plus ions?) should have an energy density comparable to that in magnetic field. However, the operation of synchrotron losses can provide additional information, if those losses are manifested in the synchrotron spectra as steepenings of the spectral-energy distribution above some characteristic frequency often called a "break" (though it is more typically a gradual curvature). A source of known age, if it has been accelerating particles continuously, will have such a break above the energy at which particle radiative lifetimes equal the source age, and this can give B. However, in spatially resolved sources such as supernova remnants (SNRs) and pulsar-wind nebulae (PWNe), systematic advection of particles, if at a known rate, gives a second measure of particle age to compare with radiative lifetimes. In most young SNRs, synchrotron X-rays make a contribution to the X-ray spectrum, and are usually found in thin rims at the remnant edges. If the rims are thin in the radial direction due to electron energy losses, a magnetic-field strength can be estimated. I present recent modeling of this process, along with models in which rims are thin due to decay of magnetic turbulence, and apply them to the remnants of SN 1006 and Tycho. In PWNe, outflows of relativistic plasma behind the pulsar wind termination shock are likely quite inhomogeneous, so magnetic-field estimates based on source lifetimes and assuming spatial uniformity can give misleading values for B. I shall discuss inhomogeneous PWN models and the effects they can have on B estimates.

Sirepo for Synchrotron Radiation Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagler, Robert; Moeller, Paul; Rakitin, Maksim

Sirepo is an open source framework for cloud computing. The graphical user interface (GUI) for Sirepo, also known as the client, executes in any HTML5 compliant web browser on any computing platform, including tablets. The client is built in JavaScript, making use of the following open source libraries: Bootstrap, which is fundamental for cross-platform web applications; AngularJS, which provides a model–view–controller (MVC) architecture and GUI components; and D3.js, which provides interactive plots and data-driven transformations. The Sirepo server is built on the following Python technologies: Flask, which is a lightweight framework for web development; Jinja, which is a secure andmore » widely used templating language; and Werkzeug, a utility library that is compliant with the WSGI standard. We use Nginx as the HTTP server and proxy, which provides a scalable event-driven architecture. The physics codes supported by Sirepo execute inside a Docker container. One of the codes supported by Sirepo is the Synchrotron Radiation Workshop (SRW). SRW computes synchrotron radiation from relativistic electrons in arbitrary magnetic fields and propagates the radiation wavefronts through optical beamlines. SRW is open source and is primarily supported by Dr. Oleg Chubar of NSLS-II at Brookhaven National Laboratory.« less

Power inverter implementing phase skipping control

DOEpatents

Somani, Utsav; Amirahmadi, Ahmadreza; Jourdan, Charles; Batarseh, Issa

2016-10-18

A power inverter includes a DC/AC inverter having first, second and third phase circuitry coupled to receive power from a power source. A controller is coupled to a driver for each of the first, second and third phase circuitry (control input drivers). The controller includes an associated memory storing a phase skipping control algorithm, wherein the controller is coupled to receive updating information including a power level generated by the power source. The drivers are coupled to control inputs of the first, second and third phase circuitry, where the drivers are configured for receiving phase skipping control signals from the controller and outputting mode selection signals configured to dynamically select an operating mode for the DC/AC inverter from a Normal Control operation and a Phase Skipping Control operation which have different power injection patterns through the first, second and third phase circuitry depending upon the power level.

A new optical head tracing reflected light for nanoprofiler

NASA Astrophysics Data System (ADS)

Okuda, K.; Okita, K.; Tokuta, Y.; Kitayama, T.; Nakano, M.; Kudo, R.; Yamamura, K.; Endo, K.

2014-09-01

High accuracy optical elements are applied in various fields. For example, ultraprecise aspherical mirrors are necessary for developing third-generation synchrotron radiation and XFEL (X-ray Free Electron LASER) sources. In order to make such high accuracy optical elements, it is necessary to realize the measurement of aspherical mirrors with high accuracy. But there has been no measurement method which simultaneously achieves these demands yet. So, we develop the nanoprofiler that can directly measure the any surfaces figures with high accuracy. The nanoprofiler gets the normal vector and the coordinate of a measurement point with using LASER and the QPD (Quadrant Photo Diode) as a detector. And, from the normal vectors and their coordinates, the three-dimensional figure is calculated. In order to measure the figure, the nanoprofiler controls its five motion axis numerically to make the reflected light enter to the QPD's center. The control is based on the sample's design formula. We measured a concave spherical mirror with a radius of curvature of 400 mm by the deflection method which calculates the figure error from QPD's output, and compared the results with those using a Fizeau interferometer. The profile was consistent within the range of system error. The deflection method can't neglect the error caused from the QPD's spatial irregularity of sensitivity. In order to improve it, we have contrived the zero method which moves the QPD by the piezoelectric motion stage and calculates the figure error from the displacement.

Bismuth ferrite dielectric nanoparticles excited at telecom wavelengths as multicolor sources by second, third, and fourth harmonic generation.

PubMed

Riporto, Jérémy; Demierre, Alexis; Kilin, Vasyl; Balciunas, Tadas; Schmidt, Cédric; Campargue, Gabriel; Urbain, Mathias; Baltuska, Andrius; Le Dantec, Ronan; Wolf, Jean-Pierre; Mugnier, Yannick; Bonacina, Luigi

2018-05-03

We demonstrate the simultaneous generation of second, third, and fourth harmonics from a single dielectric bismuth ferrite nanoparticle excited using a telecom fiber laser at 1560 nm. We first characterize the signals associated with different nonlinear orders in terms of spectrum, excitation intensity dependence, and relative signal strengths. Successively, on the basis of the polarization-resolved emission curves of the three harmonics, we discuss the interplay of susceptibility tensor components at different orders and show how polarization can be used as an optical handle to control the relative frequency conversion properties.

Brookhaven highlights. Report on research, October 1, 1992--September 30, 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowe, M.S.; Belford, M.; Cohen, A.

This report highlights the research activities of Brookhaven National Laboratory during the period dating from October 1, 1992 through September 30, 1993. There are contributions to the report from different programs and departments within the laboratory. These include technology transfer, RHIC, Alternating Gradient Synchrotron, physics, biology, national synchrotron light source, applied science, medical science, advanced technology, chemistry, reactor physics, safety and environmental protection, instrumentation, and computing and communications.

Very low-dose (0.15 mGy) chest CT protocols using the COPDGene 2 test object and a third-generation dual-source CT scanner with corresponding third-generation iterative reconstruction software.

PubMed

Newell, John D; Fuld, Matthew K; Allmendinger, Thomas; Sieren, Jered P; Chan, Kung-Sik; Guo, Junfeng; Hoffman, Eric A

2015-01-01

The purpose of this study was to evaluate the impact of ultralow radiation dose single-energy computed tomographic (CT) acquisitions with Sn prefiltration and third-generation iterative reconstruction on density-based quantitative measures of growing interest in phenotyping pulmonary disease. The effects of both decreasing dose and different body habitus on the accuracy of the mean CT attenuation measurements and the level of image noise (SD) were evaluated using the COPDGene 2 test object, containing 8 different materials of interest ranging from air to acrylic and including various density foams. A third-generation dual-source multidetector CT scanner (Siemens SOMATOM FORCE; Siemens Healthcare AG, Erlangen, Germany) running advanced modeled iterative reconstruction (ADMIRE) software (Siemens Healthcare AG) was used.We used normal and very large body habitus rings at dose levels varying from 1.5 to 0.15 mGy using a spectral-shaped (0.6-mm Sn) tube output of 100 kV(p). Three CT scans were obtained at each dose level using both rings. Regions of interest for each material in the test object scans were automatically extracted. The Hounsfield unit values of each material using weighted filtered back projection (WFBP) at 1.5 mGy was used as the reference value to evaluate shifts in CT attenuation at lower dose levels using either WFBP or ADMIRE. Statistical analysis included basic statistics, Welch t tests, multivariable covariant model using the F test to assess the significance of the explanatory (independent) variables on the response (dependent) variable, and CT mean attenuation, in the multivariable covariant model including reconstruction method. Multivariable regression analysis of the mean CT attenuation values showed a significant difference with decreasing dose between ADMIRE and WFBP. The ADMIRE has reduced noise and more stable CT attenuation compared with WFBP. There was a strong effect on the mean CT attenuation values of the scanned materials for ring size (P < 0.0001) and dose level (P < 0.0001). The number of voxels in the region of interest for the particular material studied did not demonstrate a significant effect (P > 0.05). The SD was lower with ADMIRE compared with WFBP at all dose levels and ring sizes (P < 0.05). The third-generation dual-source CT scanners using third-generation iterative reconstruction methods can acquire accurate quantitative CT images with acceptable image noise at very low-dose levels (0.15 mGy). This opens up new diagnostic and research opportunities in CT phenotyping of the lung for developing new treatments and increased understanding of pulmonary disease.

Brookhaven National Laboratory technology transfer report, fiscal year 1987

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1987-01-01

The Brookhaven Office of Research and Technology Applications (ORTA) inaugurated two major initiatives. The effort by our ORTA in collaboration with the National Synchrotron Light Source (NSLS) has succeeded in alerting American industry to the potential of using a synchrotron x-ray source for high resolution lithography. We are undertaking a preconstruction study for the construction of a prototype commercial synchrotron and development of an advanced commercial cryogenic synchrotron (XLS). ORTA sponsored a technology transfer workshop where industry expressed its views on how to transfer accelerator technology during the construction of the prototype commercial machine. The Northeast Regional utility Initiative broughtmore » 14 utilities to a workshop at the Laboratory in November. One recommendation of this workshop was to create a Center at the Laboratory for research support on issues of interest to utilities in the region where BNL has unique capability. The ORTA has initiated discussions with the New York State Science and Technology Commission, Cornell University's world renowned Nannofabrication Center and the computer aided design capabilities at SUNY at Stony Brook to create, centered around the NSLS and the XLS, the leading edge semiconductor process technology development center when the XLS becomes operational in two and a half years. 1 fig.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hettiarachchi, Ganga M.; Donner, Erica; Doelsch, Emmanuel

To understand the biogeochemistry of nutrients and contaminants in environmental media, their speciation and behavior under different conditions and at multiple scales must be determined. Synchrotron radiation-based X-ray techniques allow scientists to elucidate the underlying mechanisms responsible for nutrient and contaminant mobility, bioavailability, and behavior. The continuous improvement of synchrotron light sources and X-ray beamlines around the world has led to a profound transformation in the field of environmental biogeochemistry and, subsequently, to significant scientific breakthroughs. Following this introductory paper, this special collection includes 10 papers that either present targeted reviews of recent advancements in spectroscopic methods that are applicablemore » to environmental biogeochemistry or describe original research studies conducted on complex environmental samples that have been significantly enhanced by incorporating synchrotron radiation-based X-ray technique(s). We believe that the current focus on improving the speciation of ultra-dilute elements in environmental media through the ongoing optimization of synchrotron technologies (e.g., brighter light sources, improved monochromators, more efficient detectors) will help to significantly push back the frontiers of environmental biogeochemistry research. As many of the relevant techniques produce extremely large datasets, we also identify ongoing improvements in data processing and analysis (e.g., software improvements and harmonization of analytical methods) as a significant requirement for environmental biogeochemists to maximize the information that can be gained using these powerful tools.« less

High Frequency Plasma Generators for Ion Thrusters

NASA Technical Reports Server (NTRS)

Divergilio, W. F.; Goede, H.; Fosnight, V. V.

1981-01-01

The results of a one year program to experimentally adapt two new types of high frequency plasma generators to Argon ion thrusters and to analytically study a third high frequency source concept are presented. Conventional 30 cm two grid ion extraction was utilized or proposed for all three sources. The two plasma generating methods selected for experimental study were a radio frequency induction (RFI) source, operating at about 1 MHz, and an electron cyclotron heated (ECH) plasma source operating at about 5 GHz. Both sources utilize multi-linecusp permanent magnet configurations for plasma confinement. The plasma characteristics, plasma loading of the rf antenna, and the rf frequency dependence of source efficiency and antenna circuit efficiency are described for the RFI Multi-cusp source. In a series of tests of this source at Lewis Research Center, minimum discharge losses of 220+/-10 eV/ion were obtained with propellant utilization of .45 at a beam current of 3 amperes. Possible improvement modifications are discussed.

Invited Article: Refined analysis of synchrotron radiation for NIST's SURF III facility

NASA Astrophysics Data System (ADS)

Shirley, Eric L.; Furst, Mitchell; Arp, Uwe

2018-04-01

We have developed a new method for the exact calculation of synchrotron radiation for the National Institute of Standards and Technology Synchrotron Ultraviolet Radiation Facility, SURF III. Instead of using the Schwinger formula, which is only an approximation, we develop formulae based on Graf's addition theorem for Bessel functions and accurate asymptotic expansions for Hankel functions and Bessel functions. By measuring the radiation intensity profile at two distances from the storage ring, we also confirm an apparent vertical emittance that is consistent with the vertical betatron oscillations that are intentionally introduced to extend beam lifetime by spreading the electron beam spatially. Finally, we determine how much diffraction by beamline apertures enhances the spectral irradiance at an integrating sphere entrance port at the end station. This should eliminate small but treatable components of the uncertainty budget that one should consider when using SURF III or similar synchrotrons as standard, calculable sources of ultraviolet and other radiation.

Constraints on the extremely high-energy cosmic ray accelerators from classical electrodynamics

NASA Astrophysics Data System (ADS)

Aharonian, F. A.; Belyanin, A. A.; Derishev, E. V.; Kocharovsky, V. V.; Kocharovsky, Vl. V.

2002-07-01

We formulate the general requirements, set by classical electrodynamics, on the sources of extremely high-energy cosmic rays (EHECRs). It is shown that the parameters of EHECR accelerators are strongly limited not only by the particle confinement in large-scale magnetic fields or by the difference in electric potentials (generalized Hillas criterion) but also by the synchrotron radiation, the electro-bremsstrahlung, or the curvature radiation of accelerated particles. Optimization of these requirements in terms of an accelerator's size and magnetic field strength results in the ultimate lower limit to the overall source energy budget, which scales as the fifth power of attainable particle energy. Hard γ rays accompanying generation of EHECRs can be used to probe potential acceleration sites. We apply the results to several populations of astrophysical objects-potential EHECR sources-and discuss their ability to accelerate protons to 1020 eV and beyond. The possibility of gain from ultrarelativistic bulk flows is addressed, with active galactic nuclei and gamma-ray bursts being the examples.

Constraints on the extremely high-energy cosmic rays accelerators from classical electrodynamics

NASA Astrophysics Data System (ADS)

Belyanin, A.; Aharonian, F.; Derishev, E.; Kocharovsky, V.; Kocharovsky, V.

We formulate the general requirements, set by classical electrodynamics, to the sources of extremely high-energy cosmic rays (EHECRs). It is shown that the parameters of EHECR accelerators are strongly limited not only by the particle confinement in large-scale magnetic field or by the difference in electric potentials (generalized Hillas criterion), but also by the synchrotron radiation, the electro-bremsstrahlung, or the curvature radiation of accelerated particles. Optimization of these requirements in terms of accelerator's size and magnetic field strength results in the ultimate lower limit to the overall source energy budget, which scales as the fifth power of attainable particle energy. Hard gamma-rays accompanying generation of EHECRs can be used to probe potential acceleration sites. We apply the results to several populations of astrophysical objects - potential EHECR sources - and discuss their ability to accelerate protons to 1020 eV and beyond. A possibility to gain from ultrarelativistic bulk flows is addressed, with Active Galactic Nuclei and Gamma-Ray Bursts being the examples.

Improved visual delineation of the intimal flap in Stanford type A and B dissections at 3rd generation dual-source high-pitch CT angiography.

PubMed

Beeres, Martin; Bucher, Andreas M; Wichmann, Julian L; Frellesen, Claudia; Scholtz, Jan E; Albrecht, Moritz; Bodelle, Boris; Nour-Eldin, Nour-Eldin A; Lee, Clara; Kaup, Moritz; Vogl, Thomas J; Gruber-Rouh, Tatjana

2016-07-01

Evaluation of the intimal flap visibility comparing 2nd and 3rd generation dual-source high-pitch CT. Twenty-five consecutive patients with aortic dissection underwent CT angiography on a second and third generation dual-source CT scanner using prospective ECG-gated high-pitch dual-source CT acquisition mode. Contrast material, saline flush and flow rate were kept equal for optimum comparability. The visibility of the intimal flap as well as the delineation of the different vascular structures was evaluated. In 3rd generation dual-source high-pitch CT we could show a significant improvement of intimal flap visibility in aortic dissection. Especially, the far end of the dissection membrane could be better evaluated in 3rd generation high-pitch CT, reaching statistical significance (P < 0.01). 3rd Generation high-pitch CT angiography shows a better delineation of the aortic intimal flap in a small patient cohort, especially in the far ends of the dissection membrane. This might be due to higher tube power in this CT generation. However, to generalise these findings larger trials are needed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramadhar, Timothy R.; Zheng, Shao -Liang; Chen, Yu -Sheng

A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collectionmore » times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flack x absolute stereochemical determination parameter to date for these systems. The structures did not require the use of PLATON/SQUEEZE or other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine occupancies, discussion of the proper use of geometric and anisotropic displacement parameter restraints and constraints, and whether to perform solvent squeezing/masking. The single-crystal-to-single-crystal transformation process for the crystal sponges is also discussed. The presented general guidelines will be invaluable for researchers interested in using the crystalline sponge method at in-house diffraction or synchrotron facilities, will facilitate the collection and analysis of reliable high-quality data, and will allow construction of chemically and physically sensible models for guest structural determination.« less

The Impact of the SESAME Project on Science and Society in the Middle East

NASA Astrophysics Data System (ADS)

Winick, Herman

2008-04-01

SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is a UNESCO-sponsored project that is constructing an international research laboratory, closely modeled on CERN, in Jordan (www.sesame.org.jo). Ten Members of the governing Council (Bahrain, Cyprus, Egypt, Iran, Iraq, Israel, Jordan, Pakistan, Palestinian Authority, and Turkey) have responsibility for the project, led by Herwig Schopper, Council President since 1999. In late 2008 Chris Llewellyn-Smith will become Council President. SESAME was initiated by a gift from Germany of the decommissioned BESSY I facility. The BESSY I 0.8 GeV injector is now being installed in the recently completed building, funded by Jordan, as components are procured for a new 133 m circumference, 2.5 GeV third-generation storage ring with 12 locations for insertion devices. Beam line equipment has been provided by laboratories in France, UK, and US. Support also comes from EU, IAEA, ICTP, Japan Society for the Promotion of Science, the US Department of Energy and State Department, and laboratories around the world. The broad scientific program includes biomedical, environmental, and archaeological programs particularly relevant to the Middle East. Five scientific workshops and six annual Users' meetings have brought together several hundred scientists from the region, along with researchers from around the world. Training programs have enabled about 100 scientists from the region to work at synchrotron radiation laboratories. These activities have already had significant impact on science and society in the Middle East, for example leading to collaborations between scientists from countries that are not particularly friendly with each other, and to national planning emphasizing synchrotron radiation research. When research starts in 2011 this impact will grow as graduate students are trained in the region in many scientific disciplines, and scientists working abroad are attracted to return.

Operation of the Australian Store.Synchrotron for macromolecular crystallography

PubMed Central

Meyer, Grischa R.; Aragão, David; Mudie, Nathan J.; Caradoc-Davies, Tom T.; McGowan, Sheena; Bertling, Philip J.; Groenewegen, David; Quenette, Stevan M.; Bond, Charles S.; Buckle, Ashley M.; Androulakis, Steve

2014-01-01

The Store.Synchrotron service, a fully functional, cloud computing-based solution to raw X-ray data archiving and dissemination at the Australian Synchrotron, is described. The service automatically receives and archives raw diffraction data, related metadata and preliminary results of automated data-processing workflows. Data are able to be shared with collaborators and opened to the public. In the nine months since its deployment in August 2013, the service has handled over 22.4 TB of raw data (∼1.7 million diffraction images). Several real examples from the Australian crystallographic community are described that illustrate the advantages of the approach, which include real-time online data access and fully redundant, secure storage. Discoveries in biological sciences increasingly require multidisciplinary approaches. With this in mind, Store.Synchrotron has been developed as a component within a greater service that can combine data from other instruments at the Australian Synchrotron, as well as instruments at the Australian neutron source ANSTO. It is therefore envisaged that this will serve as a model implementation of raw data archiving and dissemination within the structural biology research community. PMID:25286837

Operation of the Australian Store.Synchrotron for macromolecular crystallography.

PubMed

Meyer, Grischa R; Aragão, David; Mudie, Nathan J; Caradoc-Davies, Tom T; McGowan, Sheena; Bertling, Philip J; Groenewegen, David; Quenette, Stevan M; Bond, Charles S; Buckle, Ashley M; Androulakis, Steve

2014-10-01

The Store.Synchrotron service, a fully functional, cloud computing-based solution to raw X-ray data archiving and dissemination at the Australian Synchrotron, is described. The service automatically receives and archives raw diffraction data, related metadata and preliminary results of automated data-processing workflows. Data are able to be shared with collaborators and opened to the public. In the nine months since its deployment in August 2013, the service has handled over 22.4 TB of raw data (∼1.7 million diffraction images). Several real examples from the Australian crystallographic community are described that illustrate the advantages of the approach, which include real-time online data access and fully redundant, secure storage. Discoveries in biological sciences increasingly require multidisciplinary approaches. With this in mind, Store.Synchrotron has been developed as a component within a greater service that can combine data from other instruments at the Australian Synchrotron, as well as instruments at the Australian neutron source ANSTO. It is therefore envisaged that this will serve as a model implementation of raw data archiving and dissemination within the structural biology research community.

Synchrotron Radiation X-ray Diffraction Techniques Applied to Insect Flight Muscle.

PubMed

Iwamoto, Hiroyuki

2018-06-13

X-ray fiber diffraction is a powerful tool used for investigating the molecular structure of muscle and its dynamics during contraction. This technique has been successfully applied not only to skeletal and cardiac muscles of vertebrates but also to insect flight muscle. Generally, insect flight muscle has a highly ordered structure and is often capable of high-frequency oscillations. The X-ray diffraction studies on muscle have been accelerated by the advent of 3rd-generation synchrotron radiation facilities, which can generate brilliant and highly oriented X-ray beams. This review focuses on some of the novel experiments done on insect flight muscle by using synchrotron radiation X-rays. These include diffraction recordings from single myofibrils within a flight muscle fiber by using X-ray microbeams and high-speed diffraction recordings from the flight muscle during the wing-beat of live insects. These experiments have provided information about the molecular structure and dynamic function of flight muscle in unprecedented detail. Future directions of X-ray diffraction studies on muscle are also discussed.

Multi-party quantum summation without a trusted third party based on single particles

NASA Astrophysics Data System (ADS)

Zhang, Cai; Situ, Haozhen; Huang, Qiong; Yang, Pingle

We propose multi-party quantum summation protocols based on single particles, in which participants are allowed to compute the summation of their inputs without the help of a trusted third party and preserve the privacy of their inputs. Only one participant who generates the source particles needs to perform unitary operations and only single particles are needed in the beginning of the protocols.

Giant Metrewave Radio Telescope Observations of Head–Tail Radio Galaxies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sebastian, Biny; Lal, Dharam V.; Rao, A. Pramesh, E-mail: biny@ncra.tifr.res.in

We present results from a study of seven large known head–tail radio galaxies based on observations using the Giant Metrewave Radio Telescope at 240 and 610 MHz. These observations are used to study the radio morphologies and distribution of the spectral indices across the sources. The overall morphology of the radio tails of these sources is suggestive of random motions of the optical host around the cluster potential. The presence of multiple bends and wiggles in several head–tail sources is possibly due to the precessing radio jets. We find steepening of the spectral index along the radio tails. The prevailingmore » equipartition magnetic field also decreases along the radio tails of these sources. These steepening trends are attributed to the synchrotron aging of plasma toward the ends of the tails. The dynamical ages of these sample sources have been estimated to be ∼10{sup 8} yr, which is a factor of six more than the age estimates from the radiative losses due to synchrotron cooling.« less

High-resolution one-photon absorption spectroscopy of the D2Σ- ← X2 Π system of radical OH and OD

NASA Astrophysics Data System (ADS)

Heays, A. N.; de Oliveira, N.; Gans, B.; Ito, K.; Boyé-Péronne, S.; Douin, S.; Hickson, K. M.; Nahon, L.; Loison, J. C.

2018-01-01

Vacuum-ultraviolet (VUV) photoabsorption spectra were recorded of the A2Σ+(v‧ = 0) ← X2 Π(v‧‧ = 0) , D2Σ-(v‧ = 0) ← X2 Π(v‧‧ = 0) and D2Σ-(v‧ = 1) ← X2 Π(v‧‧ = 0) bands of the OH and OD radicals generated in a plasma-discharge source using synchrotron radiation as a background continuum coupled with the VUV Fourier-transform spectrometer on the DESIRS beamline of synchrotron SOLEIL. High-resolution spectra permitted the quantification of transition frequencies, relative f-values, and natural line broadening. The f-values were absolutely calibrated with respect to a previous measurement of A2Σ+(v‧ = 0) ← X2 Π(v‧‧ = 0) (Wang et al., 1979). Lifetime broadening of the excited D2Σ-(v = 0) and D2Σ-(v = 1) levels is measured for the first time and compared with previous experimental limits, and implies a lifetime 5 times shorter than a theoretical prediction (van der Loo and Groenenboom, 2005). A local perturbation of the D2Σ-(v = 0) level in OH was found.

Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5–10 GHz frequency range

DOE PAGES

Bonetti, Stefano; Kukreja, Roopali; Chen, Zhao; ...

2015-09-10

In this study, we present a scanning transmission x-ray microscopy setup combined with a novel microwave synchronization scheme in order to study high frequency magnetization dynamics at synchrotron light sources. The sensitivity necessary to detect small changes of the magnetization on short time scales and nanometer spatial dimensions is achieved by combination of the developed excitation mechanism with a single photon counting electronics that is locked to the synchrotron operation frequency. The required mechanical stability is achieved by a compact design of the microscope. Our instrument is capable of creating direct images of dynamical phenomena in the 5-10 GHz range,more » with 35 nm resolution. When used together with circularly polarized x-rays, the above capabilities can be combined to study magnetic phenomena at microwave frequencies, such as ferromagnetic resonance (FMR) and spin waves. We demonstrate the capabilities of our technique by presenting phase resolved images of a –6 GHz nanoscale spin wave generated by a spin torque oscillator, as well as the uniform ferromagnetic precession with ~0.1° amplitude at –9 GHz in a micrometer-sized cobalt strip.« less

Investigation of the cavitating flow in injector nozzles for diesel and biodiesel

NASA Astrophysics Data System (ADS)

Zhong, Wenjun; He, Zhixia; Wang, Qian; Jiang, Zhaochen; Fu, Yanan

2013-07-01

In diesel engines, the cavitating flow in nozzles greatly affects the fuel atomization characteristics and then the subsequent combustion and exhaust emissions. At present the biodiesel is a kind of prospective alternative fuel in diesel engines, the flow characteristics for the biodiesel fuel need to be investigated. In this paper, based on the third-generation synchrotrons of Shanghai Synchrotron Radiation facility (SSRF), a high-precision three-dimension structure of testing nozzle with detailed internal geometry information was obtained using X-ray radiography for a more accurate physical model. A flow visualization experiment system with a transparent scaled-up vertical multi-hole injector nozzle tip was setup. A high resolution and speed CCD camera equipped with a long distance microscope device was used to acquire flow images of diesel and biodiesel fuel, respectively. Then, the characteristics of cavitating flow and their effects on the fuel atomization characteristics were investigated. The experimental results show that the nozzle cavitating flow of both the diesel and biodiesel fuel could be divided into four regimes: turbulent flow, cavitation inception, development of cavitation and hydraulic flip. The critical pressures of both the cavitating flow and hydraulic flip of biodiesel are higher than those of diesel. The spray cone angle increases as the cavitation occurs, but it decreases when the hydraulic flip appears. Finally, it can be concluded that the Reynolds number decreases with the increase of cavitation number, and the discharge coefficient increases with the increase of cavitation number.

Photoionization Efficiencies of Five Polycyclic Aromatic Hydrocarbons.

PubMed

Johansson, K Olof; Campbell, Matthew F; Elvati, Paolo; Schrader, Paul E; Zádor, Judit; Richards-Henderson, Nicole K; Wilson, Kevin R; Violi, Angela; Michelsen, Hope A

2017-06-15

We have measured photoionization-efficiency curves for pyrene, fluoranthene, chrysene, perylene, and coronene in the photon energy range of 7.5-10.2 eV and derived their photoionization cross-section curves in this energy range. All measurements were performed using tunable vacuum ultraviolet (VUV) radiation generated at the Advanced Light Source synchrotron at Lawrence Berkeley National Laboratory. The VUV radiation was used for photoionization, and detection was performed using a time-of-flight mass spectrometer. We measured the photoionization efficiency of 2,5-dimethylfuran simultaneously with those of pyrene, fluoranthene, chrysene, perylene, and coronene to obtain references of the photon flux during each measurement from the known photoionization cross-section curve of 2,5-dimethylfuran.

Femtosecond movies of water near interfaces at sub-Angstrom resolution

NASA Astrophysics Data System (ADS)

Coridan, Robert; Hwee Lai, Ghee; Schmidt, Nathan; Abbamonte, Peter; Wong, Gerard C. L.

2010-03-01

The behavior of liquid water near interfaces with nanoscopic variations in chemistry influences a broad range of phenomena in biology. Using inelastic x-ray scattering (IXS) data from 3rd-generation synchrotron x-ray sources, we reconstruct the Greens function of liquid water, which describes the å-scale spatial and femtosecond-scale temporal evolution of density fluctuations. We extend this response function formalism to reconstruct the evolution of hydration structures near dynamic surfaces with different charge distributions, in order to define more precisely the molecular signature of hydrophilicity and hydrophobicity. Moreover, we investigate modifications to surface hydration structures and dynamics as the size of hydrophilic and hydrophobic patches are varied.

Hybrid materials with an increased resistance to hard X-rays using fullerenes as radical sponges.

PubMed

Pinna, Alessandra; Malfatti, Luca; Piccinini, Massimo; Falcaro, Paolo; Innocenzi, Plinio

2012-07-01

The protection of organic and hybrid organic-inorganic materials from X-ray damage is a fundamental technological issue for broadening the range of applications of these materials. In the present article it is shown that doping hybrid films with fullerenes C(60) gives a significant reduction of damage upon exposure to hard X-rays generated by a synchrotron source. At low X-ray dose the fullerene molecules act as `radical scavengers', considerably reducing the degradation of organic species triggered by radical formation. At higher doses the gradual hydroxylation of the fullerenes converts C(60) into fullerol and a bleaching of the radical sinking properties is observed.

FR II radio galaxies at low frequencies - I. Morphology, magnetic field strength and energetics.

PubMed

Harwood, Jeremy J; Croston, Judith H; Intema, Huib T; Stewart, Adam J; Ineson, Judith; Hardcastle, Martin J; Godfrey, Leith; Best, Philip; Brienza, Marisa; Heesen, Volker; Mahony, Elizabeth K; Morganti, Raffaella; Murgia, Matteo; Orrú, Emanuela; Röttgering, Huub; Shulevski, Aleksandar; Wise, Michael W

2016-06-01

Due to their steep spectra, low-frequency observations of Fanaroff-Riley type II (FR II) radio galaxies potentially provide key insights in to the morphology, energetics and spectrum of these powerful radio sources. However, limitations imposed by the previous generation of radio interferometers at metre wavelengths have meant that this region of parameter space remains largely unexplored. In this paper, the first in a series examining FR IIs at low frequencies, we use LOFAR (LOw Frequency ARray) observations between 50 and 160 MHz, along with complementary archival radio and X-ray data, to explore the properties of two FR II sources, 3C 452 and 3C 223. We find that the morphology of 3C 452 is that of a standard FR II rather than of a double-double radio galaxy as had previously been suggested, with no remnant emission being observed beyond the active lobes. We find that the low-frequency integrated spectra of both sources are much steeper than expected based on traditional assumptions and, using synchrotron/inverse-Compton model fitting, show that the total energy content of the lobes is greater than previous estimates by a factor of around 5 for 3C 452 and 2 for 3C 223. We go on to discuss possible causes of these steeper-than-expected spectra and provide revised estimates of the internal pressures and magnetic field strengths for the intrinsically steep case. We find that the ratio between the equipartition magnetic field strengths and those derived through synchrotron/inverse-Compton model fitting remains consistent with previous findings and show that the observed departure from equipartition may in some cases provide a solution to the spectral versus dynamical age disparity.

Design and Manufacturing Criteria for Beam Position Monitor (BPM) of Taiwan Photon Source (TPS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsueh, H. P.; Chang, C. C.; Hsu, S. N.

2010-06-23

There are quite some considerations when the button feedthrough is designed and manufactured in a new 3rd generation synchrotron light source like the to-be-constructed TPS. It is the responsibility of the button feedthrough designer to design a feedthrough with the lowest probable HOM problem. It is also required for the designer to analyze the consequences for each possible mechanical error during manufacturing and therefore set standards of tolerance. We have been using MAFIA to optimize the design of feedthrough including flange type on bending chamber section and primary BPM on insertion device section. We also have set some criteria formore » feedthrough manufacturing, inspection, and welding based on hands-on experience on feedthrough electrical properties measuring, sorting, inspection, and laser welding. Here we will present the MAFIA results, electrical measurement results, and laser welding results and analysis. Criteria based on these results will also be presented.« less

Design and Manufacturing Criteria for Beam Position Monitor (BPM) of Taiwan Photon Source (TPS)

NASA Astrophysics Data System (ADS)

Hsueh, H. P.; Chang, C. C.; Hsu, S. N.; Huang, I. T.; Chen, Y. B.; Kuan, C. K.; Hsiung, G. Y.; Chen, J. R.

2010-06-01

There are quite some considerations when the button feedthrough is designed and manufactured in a new 3rd generation synchrotron light source like the to-be-constructed TPS. It is the responsibility of the button feedthrough designer to design a feedthrough with the lowest probable HOM problem. It is also required for the designer to analyze the consequences for each possible mechanical error during manufacturing and therefore set standards of tolerance. We have been using MAFIA to optimize the design of feedthrough including flange type on bending chamber section and primary BPM on insertion device section. We also have set some criteria for feedthrough manufacturing, inspection, and welding based on hands-on experience on feedthrough electrical properties measuring, sorting, inspection, and laser welding. Here we will present the MAFIA results, electrical measurement results, and laser welding results and analysis. Criteria based on these results will also be presented.

CARNAÚBA: The Coherent X-Ray Nanoprobe Beamline for the Brazilian Synchrotron SIRIUS/LNLS

NASA Astrophysics Data System (ADS)

Tolentino, Hélio C. N.; Soares, Márcio M.; Perez, Carlos A.; Vicentin, Flávio C.; Abdala, Dalton B.; Galante, Douglas; Teixeira, Verônica de C.; de Araújo, Douglas H. C.; Westfahl, Harry, Jr.

2017-06-01

The CARNAÚBA beamline is the tender-to-hard X-ray (2 - 15 keV) scanning nanoprobe planned for the 4th generation storage ring SIRIUS at the LNLS. CARNAÚBA uses an undulator source with vertical linear polarization in a low-beta straight section and grazing incidence-focusing mirrors to create a nanoprobe at 143 m from the source. The beamline optic is based on KB mirrors and provides high brilliance at an achromatic focal spot down to the diffraction limit diameter of ˜30 nm with a working distance of ˜6 cm. These characteristics are crucial for studying nanometric samples in experiments involving complex stages and environments. The CARNAÚBA beamline aims to perform raster scans using x-ray fluorescence, x-ray absorption spectroscopy, x-ray diffraction and coherent x-ray imaging techniques. Computed tomography will extend these methods to three dimensions.

The broad band X-ray spectrum of SN 1978k and two other luminous X-ray sources in the spiral galaxy NGC 1313

NASA Technical Reports Server (NTRS)

Petre, Robert; Okada, Kyoko; Mihara, Tatehiro; Makishima, Kazuo; Colbert, Edward J. M.

1994-01-01

We present preliminary results of our analysis of the Advanced Satellite for Cosmology and Astrophysics (ASCA) PV phase observation of the nearby spiral galaxy NGC 1313. ASCA cleanly resolves the three previously known luminous sources, one of which is the very luminous supernova, SN 1978k. The spectrum of SN 1978k is described by either a power law with a photon index gamma approximately 2.2 or a thermal model with temperature kT approximately 3.0 keV and abundances Z approximately 0.2 Z(sun). There is no evidence for strong line emission from it or from the other two sources. The spectrum of SN 1978k arises either in shocked gas in extreme departure from ionization equilibrium or from synchrotron processes associated with a newborn pulsar. A second source, near the galactic center, is well-fit by a power-law with a photon index of approximately 1.8. It is possibly an active nucleus-like source, but physically displaced from the optical nucleus of the galaxy. The spectrum of the third source, located 8 kpc south of the nucleus, along with the absence of an optical counterpart, suggests that it is a low mass X-ray binary; but its high X-ray luminosity clouds this interpretation. This observation demonstrates the ability of ASCA to perform effective broad band spectroscopic measurements of sources at a 2-10 keV flux level of 5 x 10(exp -13) erg cm(exp -2) s(exp -1).

Jet-Cooled Spectroscopy on the Ailes Infrared Beamline of the Synchrotron Radiation Facility Soleil

NASA Astrophysics Data System (ADS)

Georges, Robert

2015-06-01

The Advanced Infrared Line Exploited for Spectroscopy (AILES) extracts the bright far infrared (FIR) synchrotron continuum of the third generation radiation facility SOLEIL. This beamline is equipped with a high resolution (10-3 cm-1) Bruker IFS125 Fourier transform spectrometer which can be operated in the FIR but also in the mid and near infrared by using its internal conventional sources. The jet-AILES consortium (IPR, PhLAM, MONARIS, SOLEIL) has implemented a supersonic-jet apparatus on the beamline to record absorption spectra at very low temperature (5-50 K) and in highly supersaturated gaseous conditions. Heatable slit-nozzles of various lengths and widths are used to set properly the stagnation conditions. A mechanical pumping (roots pumps) was preferred for its ability to evacuate important mass flow rates and therefore to boost the experimental sensitivity of the set-up, the counterpart being a non-negligible consumption of both carrier (argon, helium or nitrogen) and spectroscopic gases. Various molecular systems were investigated up to now using the Jet-AILES apparatus. The very low temperature achieved in the gas expansion was either used to simplify the rotation-vibration structure of monomers, such as SF6, CF4 or naphthalene, or to stabilize the formation of weakly bonded molecular complexes such as the trimer of HF or the dimer of acetic acid. The nucleation of water vapor and the nuclear spin conversion of water were also investigated under free-jet conditions in the mid infrared. High-resolution spectroscopy and analysis of the νb{2} + νb{3} combination band of SF6 in a supersonic jet expansion. V. Boudon, P. Asselin, P. Soulard, M. Goubet, T. R. Huet, R. Georges, O. Pirali, P. Roy, Mol. Phys. 111, 2154-2162 (2013) The far infrared spectrum of naphthalene characterized by high resolution synchrotron FTIR spectroscopy and anharmonic DFT calculations. O. Pirali, M. Goubet, T.R. Huet, R. Georges, P. Soulard, P. Asselin, J. Courbe, P. Roy and M. Vervloet, Phys. Chem. Chem. Phys. 15, 10141-10150 (2013) The cyclic ground state structure of the HF trimer revealed by far-infrared jet-cooled Fourier transform spectroscopy. P. Asselin, P. Soulard, B. Madebène, M. Goubet, T. R. Huet, R. Georges, O. Pirali and P. Roy, Phys. Chem. Chem. Phys. 16(10), 4797-806 (2014) Standard free energy of the equilibrium between the trans-monomer and the cyclic-dimer of acetic acid in the gas phase from infrared spectroscopy. M. Goubet, P. Soulard, O. Pirali, P. Asselin, F. Réal, S. Gruet, T. R. Huet, P. Roy and R. Georges, Phys. Chem. Chem. Phys. DOI: 10.1039/c4cp05684a

CARS molecular fingerprinting using a sub-nanosecond supercontinuum light source

NASA Astrophysics Data System (ADS)

Kano, Hideaki; Akiyama, Toshihiro; Inoko, Akihito; Kobayashi, Tsubasa; Leproux, Philippe; Couderc, Vincent; Kaji, Yuichi; Oshika, Tetsuro

2018-02-01

We have visualized living cells and tissues using an ultrabroadband multiplex coherent anti-Stokes Raman scattering (CARS) microspectroscopic system by using a sub-nanosecond supercontinuum (SC) light source. Owing to the ultrabroadband spectral profile of the SC, we can generate multiplex CARS signals in the spectral range of 500-3800 cm-1, which covers the whole molecular fingerprint region, as well as the C-H and O-H stretching regions. Through the combination of the ultrabroadband multiplex CARS method with second harmonic generation (SHG) and third harmonic generation (THG) processes, we have successfully performed selective imaging of ciliary rootlet-composing Rootletin filaments in rat retina.

Multi-watt, multi-octave, mid-infrared femtosecond source

PubMed Central

Hussain, Syed A.; Hartung, Alexander; Zawilski, Kevin T.; Schunemann, Peter G.; Habel, Florian; Pervak, Vladimir

2018-01-01

Spectroscopy in the wavelength range from 2 to 11 μm (900 to 5000 cm−1) implies a multitude of applications in fundamental physics, chemistry, as well as environmental and life sciences. The related vibrational transitions, which all infrared-active small molecules, the most common functional groups, as well as biomolecules like proteins, lipids, nucleic acids, and carbohydrates exhibit, reveal information about molecular structure and composition. However, light sources and detectors in the mid-infrared have been inferior to those in the visible or near-infrared, in terms of power, bandwidth, and sensitivity, severely limiting the performance of infrared experimental techniques. This article demonstrates the generation of femtosecond radiation with up to 5 W at 4.1 μm and 1.3 W at 8.5 μm, corresponding to an order-of-magnitude average power increase for ultrafast light sources operating at wavelengths longer than 5 μm. The presented concept is based on power-scalable near-infrared lasers emitting at a wavelength near 1 μm, which pump optical parametric amplifiers. In addition, both wavelength tunability and supercontinuum generation are reported, resulting in spectral coverage from 1.6 to 10.2 μm with power densities exceeding state-of-the-art synchrotron sources over the entire range. The flexible frequency conversion scheme is highly attractive for both up-conversion and frequency comb spectroscopy, as well as for a variety of time-domain applications. PMID:29713685

GigaGauss solenoidal magnetic field inside bubbles excited in under-dense plasma

PubMed Central

Lécz, Zs.; Konoplev, I. V.; Seryi, A.; Andreev, A.

2016-01-01

This paper proposes a novel and effective method for generating GigaGauss level, solenoidal quasi-static magnetic fields in under-dense plasma using screw-shaped high intensity laser pulses. This method produces large solenoidal fields that move with the driving laser pulse and are collinear with the accelerated electrons. This is in contrast with already known techniques which rely on interactions with over-dense or solid targets and generates radial or toroidal magnetic field localized at the stationary target. The solenoidal field is quasi-stationary in the reference frame of the laser pulse and can be used for guiding electron beams. It can also provide synchrotron radiation beam emittance cooling for laser-plasma accelerated electron and positron beams, opening up novel opportunities for designs of the light sources, free electron lasers, and high energy colliders based on laser plasma acceleration. PMID:27796327

GigaGauss solenoidal magnetic field inside bubbles excited in under-dense plasma

NASA Astrophysics Data System (ADS)

Lécz, Zs.; Konoplev, I. V.; Seryi, A.; Andreev, A.

2016-10-01

This paper proposes a novel and effective method for generating GigaGauss level, solenoidal quasi-static magnetic fields in under-dense plasma using screw-shaped high intensity laser pulses. This method produces large solenoidal fields that move with the driving laser pulse and are collinear with the accelerated electrons. This is in contrast with already known techniques which rely on interactions with over-dense or solid targets and generates radial or toroidal magnetic field localized at the stationary target. The solenoidal field is quasi-stationary in the reference frame of the laser pulse and can be used for guiding electron beams. It can also provide synchrotron radiation beam emittance cooling for laser-plasma accelerated electron and positron beams, opening up novel opportunities for designs of the light sources, free electron lasers, and high energy colliders based on laser plasma acceleration.

SOLEIL shining on the solution-state structure of biomacromolecules by synchrotron X-ray footprinting at the Metrology beamline.

PubMed

Baud, A; Aymé, L; Gonnet, F; Salard, I; Gohon, Y; Jolivet, P; Brodolin, K; Da Silva, P; Giuliani, A; Sclavi, B; Chardot, T; Mercère, P; Roblin, P; Daniel, R

2017-05-01

Synchrotron X-ray footprinting complements the techniques commonly used to define the structure of molecules such as crystallography, small-angle X-ray scattering and nuclear magnetic resonance. It is remarkably useful in probing the structure and interactions of proteins with lipids, nucleic acids or with other proteins in solution, often better reflecting the in vivo state dynamics. To date, most X-ray footprinting studies have been carried out at the National Synchrotron Light Source, USA, and at the European Synchrotron Radiation Facility in Grenoble, France. This work presents X-ray footprinting of biomolecules performed for the first time at the X-ray Metrology beamline at the SOLEIL synchrotron radiation source. The installation at this beamline of a stopped-flow apparatus for sample delivery, an irradiation capillary and an automatic sample collector enabled the X-ray footprinting study of the structure of the soluble protein factor H (FH) from the human complement system as well as of the lipid-associated hydrophobic protein S3 oleosin from plant seed. Mass spectrometry analysis showed that the structural integrity of both proteins was not affected by the short exposition to the oxygen radicals produced during the irradiation. Irradiated molecules were subsequently analysed using high-resolution mass spectrometry to identify and locate oxidized amino acids. Moreover, the analyses of FH in its free state and in complex with complement C3b protein have allowed us to create a map of reactive solvent-exposed residues on the surface of FH and to observe the changes in oxidation of FH residues upon C3b binding. Studies of the solvent accessibility of the S3 oleosin show that X-ray footprinting offers also a unique approach to studying the structure of proteins embedded within membranes or lipid bodies. All the biomolecular applications reported herein demonstrate that the Metrology beamline at SOLEIL can be successfully used for synchrotron X-ray footprinting of biomolecules.

600 eV falcon-linac thomson x-ray source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crane, J K; LeSage, G P; Ditmire, T

2000-12-15

The advent of 3rd generation light sources such as the Advanced Light Source (ALS) at LBL, and the Advanced Photon Source at Argonne, have produced a revolution in x-ray probing of dense matter during the past decade. These machines use electron-synchrotrons in conjunction with undulator stages to produce 100 psec x-ray pulses with photon energies of several kiloelectronvolts (keV). The applications for x-ray probing of matter are numerous and diverse with experiments in medicine and biology, semiconductors and materials science, and plasma and solid state physics. In spite of the success of the 3rd generation light sources there is strongmore » motivation to push the capabilities of x-ray probing into new realms, requiring shorter pulses, higher brightness and harder x-rays. A 4th generation light source, the Linac Coherent Light Source (LCLS), is being considered at the Stanford Linear Accelerator [1]. The LCLS will produce multi-kilovolt x-rays of subpicosecond duration that are 10 orders of magnitude brighter than today's 3rd generation light sources.[1] Although the LCLS will provide unprecedented capability for performing time-resolved x-ray probing of ultrafast phenomena at solid densities, this machine will not be completed for many years. In the meantime there is a serious need for an ultrashort-pulse, high-brightness, hard x-ray source that is capable of probing deep into high-Z solid materials to measure dynamic effects that occur on picosecond time scales. Such an instrument would be ideal for probing the effects of shock propagation in solids using Bragg and Laue diffraction. These techniques can be used to look at phase transitions, melting and recrystallization, and the propagation of defects and dislocations well below the surface in solid materials. [2] These types of dynamic phenomena undermine the mechanical properties of metals and are of general interest in solid state physics, materials science, metallurgy, and have specific relevance to stockpile stewardship. Another x-ray diagnostic technique, extended x-ray absorption fine structure (EXAFS) spectroscopy, can be used to measure small-scale structural changes to understand the underlying atomic physics associated with the formation of defects. [2]« less

Rapid biodiagnostic ex vivo imaging at 1 μm pixel resolution with thermal source FTIR FPA.

PubMed

Findlay, C R; Wiens, R; Rak, M; Sedlmair, J; Hirschmugl, C J; Morrison, Jason; Mundy, C J; Kansiz, M; Gough, K M

2015-04-07

A recent upgrade to the optics configuration of a thermal source FTIR microscope equipped with a focal plane array detector has enabled rapid acquisition of high magnification spectrochemical images, in transmission, with an effective geometric pixel size of ∼1 × 1 μm(2) at the sample plane. Examples, including standard imaging targets for scale and accuracy, as well as biomedical tissues and microorganisms, have been imaged with the new system and contrasted with data acquired at normal magnification and with a high magnification multi-beam synchrotron instrument. With this optics upgrade, one can now conduct rapid biodiagnostic ex vivo tissue imaging in-house, with images collected over larger areas, in less time (minutes) and with comparable quality and resolution to the best synchrotron source FTIR imaging capabilities.

One-zone synchrotron self-Compton model for the core emission of Centaurus A revisited

NASA Astrophysics Data System (ADS)

Petropoulou, M.; Lefa, E.; Dimitrakoudis, S.; Mastichiadis, A.

2014-02-01

Aims: We investigate the role of the second synchrotron self-Compton (SSC) photon generation to the multiwavelength emission from the compact regions of sources that are characterized as misaligned blazars. For this, we focus on the nearest high-energy emitting radio galaxy Centaurus A and we revisit the one-zone SSC model for its core emission. Methods: We have calculated analytically the peak luminosities of the first and second SSC components by first deriving the steady-state electron distribution in the presence of synchrotron and SSC cooling, and then by using appropriate expressions for the positions of the spectral peaks. We have also tested our analytical results against those derived from a numerical code where the full emissivities and cross-sections were used. Results: We show that the one-zone SSC model cannot account for the core emission of Centaurus A above a few GeV, where the peak of the second SSC component appears. We thus propose an alternative explanation for the origin of the high-energy (≳0.4 GeV) and TeV emission, where these are attributed to the radiation emitted by a relativistic proton component through photohadronic interactions with the photons produced by the primary leptonic component. We show that the required proton luminosities are not extremely high, i.e. ~1043 erg/s, provided that the injection spectra are modelled by a power law with a high value of the lower energy cutoff. Finally, we find that the contribution of the core emitting region of Cen A to the observed neutrino and ultra-high-energy cosmic-ray fluxes is negligible.

Diagnostic X-ray sources-present and future

NASA Astrophysics Data System (ADS)

Behling, Rolf; Grüner, Florian

2018-01-01

This paper compares very different physical principles of X-ray production to spur ideation. Since more than 120 years, bremsstrahlung from X-ray tubes has been the workhorse of medical diagnostics. Generated by X-ray segments comprised of X-ray tubes and high-voltage generators in the various medical systems, X-ray photons in the spectral range between about 16 keV and 150 keV deliver information about anatomy and function of human patients and in pre-clinical animal studies. Despite of strides to employ the wave nature of X-rays as phase sensitive means, commercial diagnostic X-ray systems available until the time of writing still rely exclusively on measuring the attenuation and scattering of X-rays by matter. Significant activities in research aim at building highly brilliant short pulse X-ray sources, based on e.g. synchrotron radiation, free electron lasers and/or laser wake-field acceleration of electrons followed by wiggling with magnetic structures or Thomson scattering in bunches of light. While both approaches, non-brilliant and brilliant sources, have different scope of application, we speculate that a combination may expand the efficacy in medical application. At this point, however, severe technical and commercial difficulties hinder closing this gap. This article may inspire further development and spark innovation in this important field.

A real-time pulsed photon dosimeter

NASA Astrophysics Data System (ADS)

Brown, David; Olsher, Richard H.; Eisen, Yosef; Rodriguez, Joseph F.

1996-02-01

Radiation sources producing short pulses of photon radiation are now widespread. Such sources include electron and proton linear accelerators, betatrons, synchrotrons, and field-emission impulse generators. It is often desirable to measure leakage and skyshine radiation from such sources in real time, on a single-pulse basis as low as 8.7 nGy (1 μR) per pulse. This paper describes the design and performance of a prototype, real-time, pulsed photon dosimeter (PPD) capable of single-pulse dose measurements over the range from 3.5 nGy to 3.5 μGy (0.4 to 400 μR). The PPD may also be operated in a multiple-pulse mode that integrates the dose from a train of radiation pulses over a 3-s period. A pulse repetition rate of up to 300 Hz is accommodated. The design is eminently suitable for packaging as a lightweight, portable, survey meter. The PPD uses a CdWO 4 scintillator optically coupled to a photodiode to generate a charge at the diode output. A pulse amplifier converts the charge to a voltage pulse. A digitizer circuit generates a burst of logic pulses whose number is proportional to the peak value of the voltage pulse. The digitizer output is recorded by a pulse counter and suitably displayed. A prototype PPD was built for testing and evaluation purposes. The performance of the PPD was evaluated with a variety of pulsed photon sources. The dynamic range, energy response, and response to multiple pulses were characterized. The experimental data confirm the viability of the PPD for pulsed photon dosimetry.

Mid-IR supercontinuum generation in ultra-low loss, dispersion-zero shifted tellurite glass fiber with extended coverage beyond 4.5 μm

NASA Astrophysics Data System (ADS)

Thapa, Rajesh; Rhonehouse, Dan; Nguyen, Dan; Wiersma, Kort; Smith, Chris; Zong, Jie; Chavez-Pirson, Arturo

2013-10-01

Mid-infrared sources are a key enabling technology for various applications such as remote chemical sensing, defense communications and countermeasures, and bio-photonic diagnostics and therapeutics. Conventional mid-IR sources include optical parametric amplifiers, quantum cascade lasers, synchrotron and free electron lasers. An all-fiber approach to generate a high power, single mode beam with extremely wide (1μm-5μm) and simultaneous wavelength coverage has significant advantages in terms of reliability (no moving parts or alignment), room temperature operation, size, weight, and power efficiency. Here, we report single mode, high power extended wavelength coverage (1μm to 5μm) supercontinuum generation using a tellurite-based dispersion managed nonlinear fiber and an all-fiber based short pulse (20 ps), single mode pump source. We have developed this mid IR supercontinuum source based on highly purified solid-core tellurite glass fibers that are waveguide engineered for dispersion-zero matching with Tm-doped pulsed fiber laser pumps. The conversion efficiency from 1922nm pump to mid IR (2μm-5μm) supercontinuum is greater than 30%, and approaching 60% for the full spectrum. We have achieved > 1.2W covering from 1μm to 5μm with 2W of pump. In particular, the wavelength region above 4μm has been difficult to cover with supercontinuum sources based on ZBLAN or chalcogenide fibers. In contrast to that, our nonlinear tellurite fibers have a wider transparency window free of unwanted absorption, and are highly suited for extending the long wavelength emission above 4μm. We achieve spectral power density at 4.1μm already exceeding 0.2mW/nm and with potential for higher by scaling of pump power.

Observations of a nearby filament of galaxy clusters with the Sardinia Radio Telescope

NASA Astrophysics Data System (ADS)

Vacca, Valentina; Murgia, M.; Loi, F. Govoni F.; Vazza, F.; Finoguenov, A.; Carretti, E.; Feretti, L.; Giovannini, G.; Concu, R.; Melis, A.; Gheller, C.; Paladino, R.; Poppi, S.; Valente, G.; Bernardi, G.; Boschin, W.; Brienza, M.; Clarke, T. E.; Colafrancesco, S.; Enßlin, T.; Ferrari, C.; de Gasperin, F.; Gastaldello, F.; Girardi, M.; Gregorini, L.; Johnston-Hollitt, M.; Junklewitz, H.; Orrù, E.; Parma, P.; Perley, R.; Taylor, G. B.

2018-05-01

We report the detection of diffuse radio emission which might be connected to a large-scale filament of the cosmic web covering a 8° × 8° area in the sky, likely associated with a z≈0.1 over-density traced by nine massive galaxy clusters. In this work, we present radio observations of this region taken with the Sardinia Radio Telescope. Two of the clusters in the field host a powerful radio halo sustained by violent ongoing mergers and provide direct proof of intra-cluster magnetic fields. In order to investigate the presence of large-scale diffuse radio synchrotron emission in and beyond the galaxy clusters in this complex system, we combined the data taken at 1.4 GHz with the Sardinia Radio Telescope with higher resolution data taken with the NRAO VLA Sky Survey. We found 28 candidate new sources with a size larger and X-ray emission fainter than known diffuse large-scale synchrotron cluster sources for a given radio power. This new population is potentially the tip of the iceberg of a class of diffuse large-scale synchrotron sources associated with the filaments of the cosmic web. In addition, we found in the field a candidate new giant radio galaxy.

Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowe, M.S.; Cohen, A.; Greenberg, D.

1991-12-31

This report highlights Brookhaven National Laboratory`s activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclear Energy, and Physics. Administrative and managerial information about Brookhaven are also disclosed. (GHH)

Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowe, M.S.; Cohen, A.; Greenberg, D.

1991-01-01

This report highlights Brookhaven National Laboratory's activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclear Energy, and Physics. Administrative and managerial information about Brookhaven are also disclosed. (GHH)

Method and devices for performing stereotactic microbeam radiation therapy

DOEpatents

Dilmanian, F. Avraham

2010-01-05

A radiation delivery system generally includes either a synchrotron source or a support frame and a plurality of microbeam delivery devices supported on the support frame, both to deliver a beam in a hemispherical arrangement. Each of the microbeam delivery devices or synchrotron irradiation ports is adapted to deliver at least one microbeam of radiation along a microbeam delivery axis, wherein the microbeam delivery axes of the plurality of microbeam delivery devices cross within a common target volume.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meyer, Eileen T.; Breiding, Peter; Georganopoulos, Markos

The Chandra X-ray observatory has discovered several dozen anomalously X-ray-bright jets associated with powerful quasars. A popular explanation for the X-ray flux from the knots in these jets is that relativistic synchrotron-emitting electrons inverse-Compton scatter cosmic microwave background (CMB) photons to X-ray energies (the IC/CMB model). This model predicts a high gamma-ray flux that should be detectable by the Fermi /Large Area Telescope (LAT) for many sources. GeV-band upper limits from Fermi /LAT for the well-known anomalous X-ray jet in PKS 0637−752 were previously shown in Meyer et al. to violate the predictions of the IC/CMB model. Previously, measurements ofmore » the jet synchrotron spectrum, important for accurately predicting the gamma-ray flux level, were lacking between radio and infrared wavelengths. Here, we present new Atacama Large Millimeter/submillimeter Array (ALMA) observations of the large-scale jet at 100, 233, and 319 GHz, which further constrain the synchrotron spectrum, supporting the previously published empirical model. We also present updated limits from the Fermi /LAT using the new “Pass 8” calibration and approximately 30% more time on source. With these deeper limits, we rule out the IC/CMB model at the 8.7 σ level. Finally, we demonstrate that complete knowledge of the synchrotron SED is critical in evaluating the IC/CMB model.« less

Advanced Compton scattering light source R&D at LLNL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albert, F; Anderson, S G; Anderson, G

2010-02-16

We report the design and current status of a monoenergetic laser-based Compton scattering 0.5-2.5 MeV {gamma}-ray source. Previous nuclear resonance fluorescence results and future linac and laser developments for the source are presented. At MeV photon energies relevant for nuclear processes, Compton scattering light sources are attractive because of their relative compactness and improved brightness above 100 keV, compared to typical 4th generation synchrotrons. Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable Mono-Energetic Gamma-Ray (MEGa-Ray) light sources based on Compton scattering between a high-brightness, relativistic electron beam and a highmore » intensity laser pulse produced via chirped-pulse amplification (CPA). A new precision, tunable gamma-ray source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energy range via Compton scattering. Based on the success of the previous Thomson-Radiated Extreme X-rays (T-REX) Compton scattering source at LLNL, the source will be used to excite nuclear resonance fluorescence lines in various isotopes; applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. After a brief presentation of successful nuclear resonance fluorescence (NRF) experiments done with T-REX, the new source design, key parameters, and current status are presented.« less

Inductive Position Sensor

NASA Technical Reports Server (NTRS)

Youngquist, Robert C. (Inventor); Simmons, Stephen M. (Inventor)

2015-01-01

An inductive position sensor uses three parallel inductors, each of which has an axial core that is an independent magnetic structure. A first support couples first and second inductors and separate them by a fixed distance. A second support coupled to a third inductor disposed between the first and second inductors. The first support and second support are configured for relative movement as distance changes from the third inductor to each of the first and second inductors. An oscillating current is supplied to the first and second inductors. A device measures a phase component of a source voltage generating the oscillating current and a phase component of voltage induced in the third inductor when the oscillating current is supplied to the first and second inductors such that the phase component of the voltage induced overlaps the phase component of the source voltage.

Nuclear Bragg scattering studies in [sup 57]Fe with synchrotron radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haustein, P.E.

1993-01-01

Studies of nuclear Bragg x-ray scattering of synchrotron radiation, using crystals of [alpha]-[sup 57]Fe[sub 2]O[sub 3], have been carried out at the NSLS at Brookhaven National Laboratory and at the Cornell University CHESS facility. These studies have demonstrated that nuclear resonance states can be used to produce filtered x-ray beams which have extremely narrow bandwidth, small angular divergence and unique polarization and temporal properties. this combination of characteristics, unobtainable with radioactive sources, makes synchrotron-based Moessbauer spectroscopy feasible and is an important complement to existing methods. A review of the experimental methodology is presented. As well as come suggestions for fullermore » exploitation of this new technique.« less

Nuclear Bragg scattering studies in {sup 57}Fe with synchrotron radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haustein, P.E.

1993-03-01

Studies of nuclear Bragg x-ray scattering of synchrotron radiation, using crystals of {alpha}-{sup 57}Fe{sub 2}O{sub 3}, have been carried out at the NSLS at Brookhaven National Laboratory and at the Cornell University CHESS facility. These studies have demonstrated that nuclear resonance states can be used to produce filtered x-ray beams which have extremely narrow bandwidth, small angular divergence and unique polarization and temporal properties. this combination of characteristics, unobtainable with radioactive sources, makes synchrotron-based Moessbauer spectroscopy feasible and is an important complement to existing methods. A review of the experimental methodology is presented. As well as come suggestions for fullermore » exploitation of this new technique.« less

New synchrotron powder diffraction facility for long-duration experiments

PubMed Central

Murray, Claire A.; Potter, Jonathan; Day, Sarah J.; Baker, Annabelle R.; Thompson, Stephen P.; Kelly, Jon; Morris, Christopher G.; Tang, Chiu C.

2017-01-01

A new synchrotron X-ray powder diffraction instrument has been built and commissioned for long-duration experiments on beamline I11 at Diamond Light Source. The concept is unique, with design features to house multiple experiments running in parallel, in particular with specific stages for sample environments to study slow kinetic systems or processes. The instrument benefits from a high-brightness X-ray beam and a large area detector. Diffraction data from the commissioning work have shown that the objectives and criteria are met. Supported by two case studies, the results from months of measurements have demonstrated the viability of this large-scale instrument, which is the world’s first dedicated facility for long-term studies (weeks to years) using synchrotron radiation. PMID:28190992

Synchrotron-based EUV lithography illuminator simulator

DOEpatents

Naulleau, Patrick P.

2004-07-27

A lithographic illuminator to illuminate a reticle to be imaged with a range of angles is provided. The illumination can be employed to generate a pattern in the pupil of the imaging system, where spatial coordinates in the pupil plane correspond to illumination angles in the reticle plane. In particular, a coherent synchrotron beamline is used along with a potentially decoherentizing holographic optical element (HOE), as an experimental EUV illuminator simulation station. The pupil fill is completely defined by a single HOE, thus the system can be easily modified to model a variety of illuminator fill patterns. The HOE can be designed to generate any desired angular spectrum and such a device can serve as the basis for an illuminator simulator.

Fevers and Chills: Separating thermal and synchrotron components in SNR spectra

NASA Astrophysics Data System (ADS)

Fedor, Emily Elizabeth; Martina-Hood, Hyourin; Stage, Michael D.

2018-06-01

Spatially-resolved spectroscopy is an extremely powerful tool in X-ray analysis of extended sources, but can be computationally difficult if a source exhibits complex morphology. For example, high-resolution Chandra data of bright Galactic supernova remnants (Cas A, Tycho, etc.) allow extractions of high-quality spectra from tens to hundreds of thousands of regions, providing a rich laboratory for localizing emission from processes such as thermal line emission, bremsstrahlung, and synchrotron. This soft-band analysis informs our understanding of the typically nonthermal hard X-ray emission observed with other lower-resolution instruments. The analysis is complicated by both projection effects and the presence of multiple emission mechanisms in some regions. In particular, identifying regions with significant nonthermal emission is critical to understanding acceleration processes in remnants. Fitting tens of thousands of regions with complex, multi-component models can be time-consuming and involve so many free parameters that little constraint can be placed on the values. Previous work by Stage & Allen ('06, '07, '11) on Cas A used a technique to identify regions dominated by the highest-cutoff synchrotron emission by fitting with a simple thermal emission model and identifying regions with anomalously high apparent temperatures (caused by presence of the high-energy tail of the synchrotron emission component). Here, we present a similar technique. We verify the previous approach and, more importantly, expand it to include a method to identify regions containing strong lower-cutoff synchrotron radiation. Such regions might be associated with the reverse-shock of a supernova. Identification of a nonthermal electron population in the interior of an SNR would have significant implications for the energy balance and emission mechanisms producing the high-energy (> 10 keV) spectrum.

Probing Photoinduced Structural Phase Transitions by Fast or Ultra-Fast Time-Resolved X-Ray Diffraction

NASA Astrophysics Data System (ADS)

Cailleau, Hervé Collet, Eric; Buron-Le Cointe, Marylise; Lemée-Cailleau, Marie-Hélène Koshihara, Shin-Ya

A new frontier in the field of structural science is the emergence of the fast and ultra-fast X-ray science. Recent developments in time-resolved X-ray diffraction promise direct access to the dynamics of electronic, atomic and molecular motions in condensed matter triggered by a pulsed laser irradiation, i.e. to record "molecular movies" during the transformation of matter initiated by light pulse. These laser pump and X-ray probe techniques now provide an outstanding opportunity for the direct observation of a photoinduced structural phase transition as it takes place. The use of X-ray short-pulse of about 100ps around third-generation synchrotron sources allows structural investigations of fast photoinduced processes. Other new X-ray sources, such as laser-produced plasma ones, generate ultra-short pulses down to 100 fs. This opens the way to femtosecond X-ray crystallography, but with rather low X-ray intensities and more limited experimental possibilities at present. However this new ultra-fast science rapidly progresses around these sources and new large-scale projects exist. It is the aim of this contribution to overview the state of art and the perspectives of fast and ultra-fast X-ray scattering techniques to study photoinduced phase transitions (here, the word ultra-fast is used for sub-picosecond time resolution). In particular we would like to largely present the contribution of crystallographic methods in comparison with optical methods, such as pump-probe reflectivity measurements, the reader being not necessary familiar with X-ray scattering. Thus we want to present which type of physical information can be obtained from the positions of the Bragg peaks, their intensity and their shape, as well as from the diffuse scattering beyond Bragg peaks. An important physical feature is to take into consideration the difference in nature between a photoinduced phase transition and conventional homogeneous photoinduced chemical or biochemical processes where molecules transform in an independent way each other. Actually the photoinduced phase transition with the establishment of the new electronic and structural oscopic order is preceded by precursor co-operative phenomena due to the formation of nano-scale correlated objects. These are the counterpart of pre-transitional fluctuations at thermal equilibrium which take place above the transition temperature (short range order preceding long range one). Moreover ultra-fast X-ray scattering will play a central role within the fascinating field of manipulating coherence, for instance to directly observe coherent atomic motions induced by a light pulse, such as optical phonons. In the first part of this contribution we present what experimental features are accessible by X-ray scattering to describe the physical picture for a photoinduced structural phase transition. The second part shows how a time-resolved X-ray scattering experiment can be performed with regards to the different pulsed X-ray sources. The first time-resolved X-ray diffraction experiments on photoinduced phase transitions are described and discussed in the third part. Finally some challenges for future are briefly indicated in the conclusion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elizondo-Decanini, Juan M.

Short pulse neutron generators are described herein. In a general embodiment, the short pulse neutron generator includes a Blumlein structure. The Blumlein structure includes a first conductive plate, a second conductive plate, a third conductive plate, at least one of an inductor or a resistor, a switch, and a dielectric material. The first conductive plate is positioned relative to the second conductive plate such that a gap separates these plates. A vacuum chamber is positioned in the gap, and an ion source is positioned to emit ions in the vacuum chamber. The third conductive plate is electrically grounded, and themore » switch is operable to electrically connect and disconnect the second conductive plate and the third conductive plate. The at least one of the resistor or the inductor is coupled to the first conductive plate and the second conductive plate.« less

Compton scattering of self-absorbed synchrotron emission

NASA Astrophysics Data System (ADS)

Gao, He; Lei, Wei-Hua; Wu, Xue-Feng; Zhang, Bing

2013-11-01

Synchrotron self-Compton (SSC) scattering is an important emission mechanism in many astronomical sources, such as gamma-ray bursts (GRBs) and active galactic nuclei. We give a complete presentation of the analytical approximations for the Compton scattering of synchrotron emission with both weak and strong synchrotron self-absorption. All possible orders of the characteristic synchrotron spectral breaks (νa, νm and νc) are studied. In the weak self-absorption regime, i.e. νa < νc, the electron energy distribution is not modified by the self-absorption process. The shape of the SSC component broadly resembles that of synchrotron, but with the following features: The SSC flux increases linearly with frequency up to the SSC break frequency corresponding to the self-absorption frequency νa; and the presence of a logarithmic term in the high-frequency range of the SSC spectra makes it harder than the power-law approximation. In the strong absorption regime, i.e. νa > νc, heating of low-energy electrons due to synchrotron absorption leads to pile-up of electrons, and form a thermal component besides the broken power-law component. This leads to two-component (thermal + non-thermal) spectra for both the synchrotron and SSC spectral components. For νc < νa < νm, the spectrum is thermal (non-thermal) dominated if ν _a > √{ν _m ν _c} (ν _a < √{ν _m ν _c}). Similar to the weak-absorption regime, the SSC spectral component is broader than the simple broken power-law approximation. We derive the critical condition for strong absorption (electron pile-up), and discuss a case of GRB reverse shock emission in a wind medium, which invokes νa > max(νm, νc).

Flame experiments at the advanced light source: new insights into soot formation processes.

PubMed

Hansen, Nils; Skeen, Scott A; Michelsen, Hope A; Wilson, Kevin R; Kohse-Höinghaus, Katharina

2014-05-26

The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory(1-4). This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range(5,6). The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species' profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates(7). The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles(4). The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation of the observed large polycyclic aromatic hydrocarbons (PAHs).

Flame Experiments at the Advanced Light Source: New Insights into Soot Formation Processes

PubMed Central

Hansen, Nils; Skeen, Scott A.; Michelsen, Hope A.; Wilson, Kevin R.; Kohse-Höinghaus, Katharina

2014-01-01

The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory1-4. This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range5,6. The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species’ profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates7. The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles4. The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation of the observed large polycyclic aromatic hydrocarbons (PAHs). PMID:24894694

Brookhaven National Laboratory

MedlinePlus

... Sciences Center for Functional Nanomaterials Chemistry Condensed Matter Physics & Materials Science National Synchrotron Light Source II Sustainable ... and Technology Nonproliferation and National Security Nuclear & Particle ... Magnet RIKEN BNL ...

Is the GeV-TeV emission of PKS 0447-439 from the proton synchrotron radiation?

NASA Astrophysics Data System (ADS)

Gao, Quan-Gui; Lu, Fang-Wu; Ma, Ju; Ren, Ji-Yang; Li, Huai-Zhen

2018-06-01

We study the multi-wavelength emission features of PKS 0447-439 in the frame of the one-zone homogeneous lepto-hadronic model. In this model, we assumed that the steady power-laws with exponential cut-offs distributions of protons and electrons are injected into the source. The non-linear time-dependent kinematic equations, describing the evolution of protons, electrons and photons, are defined; these equations self-consistently involve synchrotron radiation of protons, photon-photon interaction, synchrotron radiation of electron/positron pairs, inverse Compton scattering and synchrotron self-absorption. The model is applied to reproduce the multi-wavelength spectrum of PKS 0447-439. Our results indicate that the spectral energy distribution (SED) of PKS 0447-439 can be reproduced well by the model. In particular, the GeV-TeV emission is produced by the synchrotron radiation of relativistic protons. The physically plausible solutions require the magnetic strength 10 G≲ B ≲ 100 G. We found that the observed spectrum of PKS 0447-439 can be reproduced well by the model whether z = 0.16 or z = 0.2, and the acceptable upper limit of redshift is z=0.343.

Resonant circuit which provides dual-frequency excitation for rapid cycling of an electromagnet

DOEpatents

Praeg, W.F.

1982-03-09

Disclosed is a novel ring-magnet control circuit that permits synchrotron repetition rates much higher than the frequency of the sinusoidal guide field of the ring magnet during particle acceleration. The control circuit generates sinusoidal excitation currents of different frequencies in the half waves. During radio-frequency acceleration of the synchrotron, the control circuit operates with a lower frequency sine wave and, thereafter, the electromagnets are reset with a higher-frequency half sine wave.

Time-resolved measurements of supersonic fuel sprays using synchrotron X-rays.

PubMed

Powell, C F; Yue, Y; Poola, R; Wang, J

2000-11-01

A time-resolved radiographic technique has been developed for probing the fuel distribution close to the nozzle of a high-pressure single-hole diesel injector. The measurement was made using X-ray absorption of monochromatic synchrotron-generated radiation, allowing quantitative determination of the fuel distribution in this optically impenetrable region with a time resolution of better than 1 micros. These quantitative measurements constitute the most detailed near-nozzle study of a fuel spray to date.

Low-aberration beamline optics for synchrotron infrared nanospectroscopy.

PubMed

Freitas, Raul O; Deneke, Christoph; Maia, Francisco C B; Medeiros, Helton G; Moreno, Thierry; Dumas, Paul; Petroff, Yves; Westfahl, Harry

2018-04-30

Synchrotron infrared nanospectroscopy is a recently developed technique that enables new possibilities in the broadband chemical analysis of materials in the nanoscale, far beyond the diffraction limit in this frequency domain. Synchrotron infrared ports have exploited mainly the high brightness advantage provided by electron storage rings across the whole infrared range. However, optical aberrations in the beam produced by the source depth of bending magnet emission at large angles prevent infrared nanospectroscopy to reach its maximum capability. In this work we present a low-aberration optical layout specially designed and constructed for a dedicated synchrotron infrared nanospectroscopy beamline. We report excellent agreement between simulated beam profiles (from standard wave propagation and raytracing optics simulations) with experimental measurements. We report an important improvement in the infrared nanospectroscopy experiment related to the improved beamline optics. Finally, we demonstrate the performance of the nanospectroscopy endstation by measuring a hyperspectral image of a polar material and we evaluate the setup sensitivity by measuring ultra-thin polymer films down to 6 nm thick.

Modeling challenges and approaches in simulating the Jovian synchrotron radiation belts from an in-situ perspective

NASA Astrophysics Data System (ADS)

Adumitroaie, V.; Oyafuso, F. A.; Levin, S.; Gulkis, S.; Janssen, M. A.; Santos-Costa, D.; Bolton, S. J.

2017-12-01

In order to obtain credible atmospheric composition retrieval values from Jupiter's observed radiative signature via Juno's MWR instrument, it is necessary to separate as robustly as possible the contributions from three emission sources: CMB, planet and synchrotron radiation belts. The numerical separation requires a refinement, based on the in-situ data, of a higher fidelity model for the synchrotron emission, namely the multi-parameter, multi-zonal model of Levin at al. (2001). This model employs an empirical electron energy distribution, which prior to the Juno mission, has been adjusted exclusively from VLA observations. At minimum 8 sets of perijove observations (i.e. by PJ9) have to be delivered to an inverse model for retrieval of the electron distribution parameters with the goal of matching the synchrotron emission observed along MWR's lines of sight. The challenges and approaches taken to perform this task are discussed here. The model will be continuously improved with the availability of additional information, both from the MWR and magnetometer instruments.

Thermal Electrons in Gamma-Ray Burst Afterglows

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ressler, Sean M.; Laskar, Tanmoy

2017-08-20

To date, nearly all multi-wavelength modeling of long-duration γ -ray bursts has ignored synchrotron radiation from the significant population of electrons expected to pass the shock without acceleration into a power-law distribution. We investigate the effect of including the contribution of thermal, non-accelerated electrons to synchrotron absorption and emission in the standard afterglow model, and show that these thermal electrons provide an additional source of opacity to synchrotron self-absorption, and yield an additional emission component at higher energies. The extra opacity results in an increase in the synchrotron self-absorption frequency by factors of 10–100 for fiducial parameters. The nature ofmore » the additional emission depends on the details of the thermal population, but is generally observed to yield a spectral peak in the optical brighter than radiation from the nonthermal population by similar factors a few seconds after the burst, remaining detectable at millimeter and radio frequencies several days later.« less

Pump-probe experiments at the TEMPO beamline using the low-α operation mode of Synchrotron SOLEIL.

PubMed

Silly, Mathieu G; Ferté, Tom; Tordeux, Marie Agnes; Pierucci, Debora; Beaulieu, Nathan; Chauvet, Christian; Pressacco, Federico; Sirotti, Fausto; Popescu, Horia; Lopez-Flores, Victor; Tortarolo, Marina; Sacchi, Maurizio; Jaouen, Nicolas; Hollander, Philippe; Ricaud, Jean Paul; Bergeard, Nicolas; Boeglin, Christine; Tudu, Bharati; Delaunay, Renaud; Luning, Jan; Malinowski, Gregory; Hehn, Michel; Baumier, Cédric; Fortuna, Franck; Krizmancic, Damjan; Stebel, Luigi; Sergo, Rudi; Cautero, Giuseppe

2017-07-01

The SOLEIL synchrotron radiation source is regularly operated in special filling modes dedicated to pump-probe experiments. Among others, the low-α mode operation is characterized by shorter pulse duration and represents the natural bridge between 50 ps synchrotron pulses and femtosecond experiments. Here, the capabilities in low-α mode of the experimental set-ups developed at the TEMPO beamline to perform pump-probe experiments with soft X-rays based on photoelectron or photon detection are presented. A 282 kHz repetition-rate femtosecond laser is synchronized with the synchrotron radiation time structure to induce fast electronic and/or magnetic excitations. Detection is performed using a two-dimensional space resolution plus time resolution detector based on microchannel plates equipped with a delay line. Results of time-resolved photoelectron spectroscopy, circular dichroism and magnetic scattering experiments are reported, and their respective advantages and limitations in the framework of high-time-resolution pump-probe experiments compared and discussed.

Prospects for compact high-intensity laser synchrotron x-ray and gamma sources

NASA Astrophysics Data System (ADS)

Pogorelsky, I. V.

1997-03-01

A laser interacting with a relativistic electron beam behaves like a virtual wiggler of an extremely short period equal to half of the laser wavelength. This approach opens a route to relatively compact, high-brightness x-ray sources alternative or complementary to conventional synchrotron light sources. Although not new, the laser synchrotron source (LSS) concept is still waiting for a convincing demonstration. Available at the BNL Accelerator Test Facility (ATF), a high-brightness electron beam and the high-power CO2 laser may be used for prototype LSS demonstration. In a feasible demonstration experiment, 10-GW, 100-ps CO2 laser beam will be brought to a head-on collision with a 10-ps, 0.5-nC, 50 MeV electron bunch. Flashes of collimated 4.7 keV (2.6 Å) x-rays of 10-ps pulse duration, with a flux of ˜1019photons/sec, will be produced via linear Compton backscattering. The x-ray spectrum is tunable proportionally to the e-beam energy. A rational short-term extension of the proposed experiment would be further enhancement of the x-ray flux to the 1022 photons/sec level, after the ongoing ATF CO2 laser upgrade to 5 TW peak power and electron bunch shortening to 3 ps is realized. In the future, exploiting the promising approach of a high-gradient laser wake field accelerator, a compact "table-top" LSS of monochromatic gamma radiation may become feasible.

Real-time data-intensive computing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parkinson, Dilworth Y., E-mail: dyparkinson@lbl.gov; Chen, Xian; Hexemer, Alexander

2016-07-27

Today users visit synchrotrons as sources of understanding and discovery—not as sources of just light, and not as sources of data. To achieve this, the synchrotron facilities frequently provide not just light but often the entire end station and increasingly, advanced computational facilities that can reduce terabytes of data into a form that can reveal a new key insight. The Advanced Light Source (ALS) has partnered with high performance computing, fast networking, and applied mathematics groups to create a “super-facility”, giving users simultaneous access to the experimental, computational, and algorithmic resources to make this possible. This combination forms an efficientmore » closed loop, where data—despite its high rate and volume—is transferred and processed immediately and automatically on appropriate computing resources, and results are extracted, visualized, and presented to users or to the experimental control system, both to provide immediate insight and to guide decisions about subsequent experiments during beamtime. We will describe our work at the ALS ptychography, scattering, micro-diffraction, and micro-tomography beamlines.« less

Corneal imaging by second and third harmonic generation microscopy

NASA Astrophysics Data System (ADS)

Brocas, Arnaud; Jay, Louis; Mottay, Eric; Brunette, Isabelle; Ozaki, Tsuneyuki

2008-02-01

Advanced imaging methods are essential tools for improved outcome of refractive surgery. Second harmonic generation (SHG) and third harmonic generation (THG) microscopy are noninvasive high-resolution imaging methods, which can discriminate the different layers of the cornea, thus having strong impact on the outcome of laser surgery. In this work, we use an Ytterbium femtosecond laser as the laser source, the longer wavelength of which reduces scattering, and allows simultaneous SHG and THG imaging. We present SHG and THG images and profiles of pig corneas that clearly show the anterior surface of the cornea, the entry in the stroma and its end, and the posterior surface of the cornea. These observations allow localizing the epithelium, the stroma and the endothelium. Other experiments give information about the structure and cytology of the corneal layers.

Help-seeking and service use for dementia in Italian, Greek and Chinese Australians.

PubMed

Low, Lee-Fay; Anstey, Kaarin J; Lackersteen, Steven M P; Camit, Michael

2011-04-01

To explore the help-seeking strategies and the acceptance of services among a national sample of Italian, Greek and Chinese compared to third generation Australians. A cross-sectional telephone survey of 350 Italian, 414 Greek, 437 Chinese and 500 third generation Australians whose households were randomly selected from the national telephone directory was carried out. Participants were asked how they would seek help for a character in a vignette with dementia and what aged care services they would use. The most frequently reported sources of help for all participants were general practitioners (55%), community organisations (27%) and family (26%). Significantly more racial minority participants reported that they would seek help from their families (32%) than did third generation Australians (13%). The percentage of participants who reported they would use aged care services were 96% for day activities, 95% for community nursing, 93% for bus outings, 91% for home help with housework, 88% for carer's support groups, 83% for nursing home care, 78% for one-week respite and 67% for Meals-on-Wheels. Racial minorities were equally or more likely to say that they would use some community-based services than third generation Australians and less likely to use residential respite. Italians were less likely to use permanent residential care. Acculturation parameters were inconsistently associated with help-seeking and service acceptability. Racial minority groups have a greater preference for community services than third generation Australians. There are differences between racial minority groups on help-seeking and acceptability of services. Education and outreach to these groups needs to be tailored.

Signatures of in-plane and out-of-plane magnetization generated by synchrotron radiation in magnetically doped and pristine topological insulators

NASA Astrophysics Data System (ADS)

Shikin, A. M.; Rybkina, A. A.; Estyunin, D. A.; Sostina, D. M.; Voroshnin, V. Yu.; Klimovskikh, I. I.; Rybkin, A. G.; Surnin, Yu. A.; Kokh, K. A.; Tereshchenko, O. E.; Petaccia, L.; Di Santo, G.; Skirdkov, P. N.; Zvezdin, K. A.; Zvezdin, A. K.; Kimura, A.; Chulkov, E. V.; Krasovskii, E. E.

2018-06-01

Possibility of in-plane and out-of-plane magnetization generated by synchrotron radiation (SR) in magnetically doped and pristine topological insulators (TIs) is demonstrated and studied by angle-resolved photoemission spectroscopy. We show experimentally and by ab initio calculations how nonequal depopulation of the Dirac cone (DC) states with opposite momenta in V-doped and pristine TIs generated by linearly polarized SR leads to the hole-generated uncompensated spin accumulation followed by the SR-induced magnetization via spin-torque effect. Moreover, the photoexcitation of the DC is asymmetric, and it varies with the photon energy. We find a relation between the photoexcitation asymmetry, the generated spin accumulation, and the induced in-plane and out-of-plane magnetic field. Experimentally the SR-generated in-plane and out-of-plane magnetization is confirmed by the k∥ shift of the DC position and by the gap opening at the Dirac point even above the Curie temperature. Theoretical predictions and estimations of the measurable physical quantities substantiate the experimental results.

Impedance measurements of the extraction kicker system for the rapid cycling synchrotron of China Spallation Neutron Source

NASA Astrophysics Data System (ADS)

Huang, Liang-Sheng; Wang, Sheng; Liu, Yu-Dong; Li, Yong; Liu, Ren-Hong; Xiao, Ou-Zheng

2016-04-01

The fast extraction kicker system is one of the most important accelerator components and the main source of impedance in the Rapid Cycling Synchrotron of the China Spallation Neutron Source. It is necessary to understand the kicker impedance before its installation into the tunnel. Conventional and improved wire methods are employed in the impedance measurement. The experimental results for the kicker impedance are explained by comparison with simulation using CST PARTICLE STUDIO. The simulation and measurement results confirm that the window-frame ferrite geometry and the end plate are the important structures causing coupling impedance. It is proved in the measurements that the mismatching from the power form network to the kicker leads to a serious oscillation sideband of the longitudinal and vertical impedance and the oscillation can be reduced by ferrite absorbing material. Supported by National Natural Science Foundation of China (11175193, 11275221)

Emphysema diagnosis using X-ray dark-field imaging at a laser-driven compact synchrotron light source

PubMed Central

Schleede, Simone; Meinel, Felix G.; Bech, Martin; Herzen, Julia; Achterhold, Klaus; Potdevin, Guillaume; Malecki, Andreas; Adam-Neumair, Silvia; Thieme, Sven F.; Bamberg, Fabian; Nikolaou, Konstantin; Bohla, Alexander; Yildirim, Ali Ö.; Loewen, Roderick; Gifford, Martin; Ruth, Ronald; Eickelberg, Oliver; Reiser, Maximilian; Pfeiffer, Franz

2012-01-01

In early stages of various pulmonary diseases, such as emphysema and fibrosis, the change in X-ray attenuation is not detectable with absorption-based radiography. To monitor the morphological changes that the alveoli network undergoes in the progression of these diseases, we propose using the dark-field signal, which is related to small-angle scattering in the sample. Combined with the absorption-based image, the dark-field signal enables better discrimination between healthy and emphysematous lung tissue in a mouse model. All measurements have been performed at 36 keV using a monochromatic laser-driven miniature synchrotron X-ray source (Compact Light Source). In this paper we present grating-based dark-field images of emphysematous vs. healthy lung tissue, where the strong dependence of the dark-field signal on mean alveolar size leads to improved diagnosis of emphysema in lung radiographs. PMID:23074250

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This report contains viewgraphs on the following topics. The advanced light source U8 undulator beamline, 20--300 eV; gas-phase actinide studies with synchrotron radiation; atomic structure calculations for heavy atoms; flux growth of single crystal uranium intermetallics: Extension to transuranics; x-ray absorption near-edge structure studies of actinide compounds; surface as a new stage for studying actinides: Theoretical study of the surface electronic structure of uranium; magnetic x-ray scattering experiments at resonant energies; beamline instruments for radioactive materials; the search for x-ray absorption magnetic circular dichroism in actinide materials: preliminary experiments using UFe[sub 2] and U-S; the laser plasma laboratory light source:more » a source of preliminary transuranic data; electron spectroscopy of heavy fermion actinide materials; study of thin layers of actinides. Present status and future use of synchrotron radiation; electronic structure and correlated-electron theory for actinide materials; and heavy fermion and kondo phenomena in actinide materials.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This report contains viewgraphs on the following topics. The advanced light source U8 undulator beamline, 20--300 eV; gas-phase actinide studies with synchrotron radiation; atomic structure calculations for heavy atoms; flux growth of single crystal uranium intermetallics: Extension to transuranics; x-ray absorption near-edge structure studies of actinide compounds; surface as a new stage for studying actinides: Theoretical study of the surface electronic structure of uranium; magnetic x-ray scattering experiments at resonant energies; beamline instruments for radioactive materials; the search for x-ray absorption magnetic circular dichroism in actinide materials: preliminary experiments using UFe{sub 2} and U-S; the laser plasma laboratory light source:more » a source of preliminary transuranic data; electron spectroscopy of heavy fermion actinide materials; study of thin layers of actinides. Present status and future use of synchrotron radiation; electronic structure and correlated-electron theory for actinide materials; and heavy fermion and kondo phenomena in actinide materials.« less

X-ray metrology of an array of active edge pixel sensors for use at synchrotron light sources

NASA Astrophysics Data System (ADS)

Plackett, R.; Arndt, K.; Bortoletto, D.; Horswell, I.; Lockwood, G.; Shipsey, I.; Tartoni, N.; Williams, S.

2018-01-01

We report on the production and testing of an array of active edge silicon sensors as a prototype of a large array. Four Medipix3RX.1 chips were bump bonded to four single chip sized Advacam active edge n-on-n sensors. These detectors were then mounted into a 2 by 2 array and tested on B16 at Diamond Light Source with an x-ray beam spot of 2um. The results from these tests, compared with optical metrology demonstrate that this type of sensor is sensitive to the physical edge of the silicon, with only a modest loss of efficiency in the final two rows of pixels. We present the efficiency maps recorded with the microfocus beam and a sample powder diffraction measurement. These results give confidence that this sensor technology can be used effectively in larger arrays of detectors at synchrotron light sources.

A compact radiation source for digital subtractive angiography

NASA Astrophysics Data System (ADS)

Wiedemann, H.; Baltay, M.; Carr, R.; Hernandez, M.; Lavender, W.

1994-08-01

Beam requirements for 33 keV radiation used in digital subtraction angiography have been established through extended experimentation first at Stanford and later at the National Synchrotron Light Source in Brookhaven. So far research and development of this medical procedure to image coronary blood vessels have been undertaken on large high energy electron storage rings. With progress in this diagnostic procedure, it is interesting to look for an optimum concept for providing a 33 keV radiation source which would fit into the environment of a hospital. A variety of competing effects and technologies to produce 33 keV radiation are available, but none of these processes provides the combination of sufficient photon flux and monochromaticity except for synchrotron radiation from an electron storage ring. The conceptual design of a compact storage ring optimized to fit into a hospital environment and producing sufficient 33 keV radiation for digital subtraction radiography will be discussed.

Status of NSLS-II Storage Ring Vacuum Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doom,L.; Hseuh,H.; Ferreira, M.

2009-05-04

National Synchrotron Light Source II (NSLS-II), being constructed at Brookhaven National Laboratory, is a 3-GeV, high-flux and high- brightness synchrotron radiation facility with a nominal current of 500 mA. The storage ring vacuum system will have extruded aluminium chambers with ante-chamber for photon fans and distributed NEG strip pumping. Discrete photon absorbers will be used to intercept the un-used bending magnet radiation. In-situ bakeout will be implemented to achieve fast conditioning during initial commissioning and after interventions.

Morphology of methane hydrate host sediments

USGS Publications Warehouse

Jones, K.W.; Feng, H.; Tomov, S.; Winters, W.J.; Eaton, M.; Mahajan, D.

2005-01-01

The morphological features including porosity and grains of methane hydrate host sediments were investigated using synchrotron computed microtomography (CMT) technique. The sediment sample was obtained during Ocean Drilling Program Leg 164 on the Blake Ridge at water depth of 2278.5 m. The CMT experiment was performed at the Brookhaven National Synchrotron Light Source facility. The analysis gave ample porosity, specific surface area, mean particle size, and tortuosity. The method was found to be highly effective for the study of methane hydrate host sediments.

Preliminary synchrotron analysis of lead in hair from a lead smelter worker

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, R.R.; Kempson, I.M.; Naftel, S.J.

2008-06-09

Synchrotron X-ray fluorescence has been used to study the distribution of lead in a hair sample collected from a lead smelter worker. A mathematical model was used to imitate the transverse scan signal based on the analysis volume and concentration profiles. The results suggest that the Pb originates both from ingestion and environmental exposure, however direct deposition from the environment is the more important source of hair lead. The model could apply equally to any other analysis involving a thin cylindrical sample.

Apparatus and method for compensating for electron beam emittance in synchronizing light sources

DOEpatents

Neil, George R.

1996-01-01

A focused optical beam is used to change the path length of the core electrons in electron light sources thereby boosting their efficiency of conversion of electron beam energy to light. Both coherent light in the free electron laser and incoherent light in the synchrotron is boosted by this technique. By changing the path length of the core electrons by the proper amount, the core electrons are caused to stay in phase with the electrons in the outer distribution of the electron beam. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron.

Apparatus and method for compensating for electron beam emittance in synchronizing light sources

DOEpatents

Neil, G.R.

1996-07-30

A focused optical beam is used to change the path length of the core electrons in electron light sources thereby boosting their efficiency of conversion of electron beam energy to light. Both coherent light in the free electron laser and incoherent light in the synchrotron is boosted by this technique. By changing the path length of the core electrons by the proper amount, the core electrons are caused to stay in phase with the electrons in the outer distribution of the electron beam. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron. 4 figs.

Nuclear resonance reflectivity from a [57Fe/Cr]30 multilayer with the Synchrotron Mössbauer Source.

PubMed

Andreeva, Marina A; Baulin, Roman A; Chumakov, Aleksandr I; Rüffer, Rudolf; Smirnov, Gennadii V; Babanov, Yurii A; Devyaterikov, Denis I; Milyaev, Mikhail A; Ponomarev, Dmitrii A; Romashev, Lazar N; Ustinov, Vladimir V

2018-03-01

Mössbauer reflectivity spectra and nuclear resonance reflectivity (NRR) curves have been measured using the Synchrotron Mössbauer Source (SMS) for a [ 57 Fe/Cr] 30 periodic multilayer, characterized by the antiferromagnetic interlayer coupling between adjacent 57 Fe layers. Specific features of the Mössbauer reflectivity spectra measured with π-polarized radiation of the SMS near the critical angle and at the `magnetic' maximum on the NRR curve are analyzed. The variation of the ratio of lines in the Mössbauer reflectivity spectra and the change of the intensity of the `magnetic' maximum under an applied external field has been used to reveal the transformation of the magnetic alignment in the investigated multilayer.

Operation of Negative Ion Sources at the Cooler Synchrotron COSY/Juelich

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gebel, R.; Felden, O.; Maier, R.

2011-09-26

The Institute for Nuclear Physics at the Forschungszentrum Juelich is dedicated to fundamental research in the field of hadron, particle and nuclear physics. Main activities are the development of the High Energy Storage Ring for the Facility for Antiproton and Ion Research at Darmstadt and the operation and improvement of the cooler synchrotron COSY at Juelich. The injector, a cyclotron with polarized and unpolarized H{sup -} and D{sup -} sources, has exceeded 7000 hours availability per year, averaged over the last decade. Work in progress is the investigation of production, extraction and transport of the low energy 4.5 keV/u ionmore » beams. A brief overview of the activities is presented.« less

The Tapered Hybrid Undulator (THUNDER) of the visible free-electron laser oscillator experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, K.E.; Quimby, D.C.; Slater, J.M.

A 5 m tapered hybrid undulator (THUNDER) has been designed and built as part of the Boeing Aerospace Company and Spectra Technology, Inc. visible free-electron laser (FEL) oscillator experiment. The performance goals required of an undulator for a visible oscillator with large extraction are ambitious. They require the establishment of stringent magnetic field quality tolerances which impact design and fabrication techniques. The performance goals of THUNDER are presented. The tolerances resulting from the FEL interaction are contrasted and compared to those of a synchrotron radiation source. The design, fabrication, and field measurements are discussed. The performance of THUNDER serves asmore » a benchmark for future wiggler/undulator design for advanced FEL's and synchrotron radiation sources.« less