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Sample records for alternating gradient synchrotron

  1. Proceedings of the workshop on heavy ion physics at the Alternating Gradient Synchrotron (AGS)

    International Nuclear Information System (INIS)

    The Workshop in Heavy Ion Physics at the Alternating Gradient Synchrotron (HIPAGS) was held at Brookhaven from March 5 to 7, 2--1/2 days. The purpose was first to demonstrate the status of the experimental program of nucleus-nucleus collisions which started in the fall of 1986 with the first 16O beam at 14.6 GeV/c per nucleon. The second objective was to present the theoretical concepts and models being applied to interpret the data. The program also included surveys of the results from the heavy ion program at the CERN-SPS, in areas that are relevant for the AGS program and discussions of future directions. The specific perspective at Brookhaven is the availability of Au beams at 11.5 GeV/c per nucleon from 1992, to which allusions were made so many times during the workshop. These proceedings are organized in the same way as the workshop program, so the list of papers is identical to the program. The workshop was very informal and very preliminary results were shown by experimentalists and theorists alike. Therefore it is strongly advised that anybody who quotes results or ideas from these proceedings, first consult with the authors of the paper being quoted. To facilitate that process, electronic mailing addresses (BITNET) are included with the list of papers and authors

  2. Programmed improvements of the alternating gradient synchrotron complex at Brookhaven National Laboratory, Upton, New York. Environmental assessment

    International Nuclear Information System (INIS)

    The purpose and need for DOE to undertake the actions described in this document are to improve the efficiency of the Alternating Gradient Synchrotron (AGS) complex. Benefits would include optimization of the AGS scientific program, increased high-energy and nuclear physics experimentation, improved health and safety conditions for workers and users, reduced impact on the environment and the general public, energy conservation, decreased generation of hazardous and radioactive wastes, and completion of actions required to permit the AGS to be the injector to the Relativistic Heavy Ion Collider (RHIC)., Improved efficiency is defined as increasing the AGS's capabilities to capture and accelerate the proton intensity transferred to the AGS from the AGS booster. Improved capture of beam intensity would reduce the beam losses which equate to lost scientific opportunity for study and increased potential for radiation doses to workers and the general public. The action would also refurbish magnets used in the transfer tunnel which connects the AGS complex to RHIC to permit smooth injection of beam into the RHIC accelerator. These magnets were previously used to direct beam to fixed targets for high energy physics studies but have hot received proper maintenance to be reliable as injectors to RHIC. The document describes alternative actions, the affected environment, and environmental impacts

  3. Fixed field alternating gradient

    OpenAIRE

    Machida, Shinji

    2013-01-01

    The concept of a fixed field alternating gradient (FFAG) accelerator was invented in the 1950s. Although many studies were carried out up to the late 1960s, there has been relatively little progress until recently, when it received widespread attention as a type of accelerator suitable for very fast acceleration and for generating high-power beams. In this paper, we describe the principles and design procedure of a FFAG accelerator.

  4. Fixed-Field Alternating-Gradient Accelerators

    OpenAIRE

    Sheehy, S. L.

    2016-01-01

    These notes provide an overview of Fixed-Field Alternating-Gradient (FFAG) accelerators for medical applications. We begin with a review of the basic principles of this type of accelerator, including the scaling and non-scaling types, highlighting beam dynamics issues that are of relevance to hadron ac- celerators. The potential of FFAG accelerators in the field of hadron therapy is discussed in detail, including an overview of existing medical FFAG designs. The options for FFAG treatment gan...

  5. Fixed-Field Alternating-Gradient Accelerators

    CERN Document Server

    Sheehy, S L

    2016-01-01

    These notes provide an overview of Fixed-Field Alternating-Gradient (FFAG) accelerators for medical applications. We begin with a review of the basic principles of this type of accelerator, including the scaling and non-scaling types, highlighting beam dynamics issues that are of relevance to hadron ac- celerators. The potential of FFAG accelerators in the field of hadron therapy is discussed in detail, including an overview of existing medical FFAG designs. The options for FFAG treatment gantries are also considered.

  6. A gradient-directed unsharp masking algorithm for synchrotron radiation angiography

    International Nuclear Information System (INIS)

    An algorithm for digital processing of synchrotron radiation digital subtraction intravenous angiographies (intravenous SYRDA) is presented. It is used in order to enhance the coronary arteries hidden behind the heart chambers and the aorta (which are normally filled with contrast medium and then are opaque). In order to remove these large structures, a gradient operator computed over a very large area is used. Some preliminary results with a synthetic image and an image taken from a human subject are also presented

  7. Matching bunched beams to alternating gradient focusing systems

    International Nuclear Information System (INIS)

    A numerical procedure for generating phase-space distributions matched to alternating gradient focusing systems has been tested. For a smooth-focusing system a matched distribution can be calculated. With a particle tracing simulation code such a distribution can be followed while adiabatically deforming the focusing forces until an alternating gradient configuration is reached. The distribution remains matched; the final distribution is periodic with the structure period. External nonlinearities, including nonlinear couplings, were included in our examples but space charge was not. This procedure is expected to work with space charge but will require a 3-D space-charge calculation in the simulation code

  8. Matching bunched beams to alternating gradient focusing systems

    International Nuclear Information System (INIS)

    A numerical procedure for generating phase-space distributions matched to alternating gradient focusing systems has been tested. For a smooth-focusing system a matched distribution can be calculated. With a particle tracing simulation code such a distribution can be followed while adiabatically deforming the focusing forces until an alternating gradient configuration is reached. The distribution remains matched; that is, the final distribution is periodic with the structure period. This method is useful because it can produce distributions matched to nonlinear forces. This is a feature that elliptical distributions, with ellipse parameters obtained from the Courant-Snyder theory, do not have. External nonlinearities, including nonlinear couplings, were included in our examples but space charge was not. This procedure is expected to work with space charge but will require a three-dimensional space charge calculation in the simulation code

  9. Alternating proximal gradient method for nonnegative matrix factorization

    CERN Document Server

    Xu, Yangyang

    2011-01-01

    Nonnegative matrix factorization has been widely applied in face recognition, text mining, as well as spectral analysis. This paper proposes an alternating proximal gradient method for solving this problem. With a uniformly positive lower bound assumption on the iterates, any limit point can be proved to satisfy the first-order optimality conditions. A Nesterov-type extrapolation technique is then applied to accelerate the algorithm. Though this technique is at first used for convex program, it turns out to work very well for the non-convex nonnegative matrix factorization problem. Extensive numerical experiments illustrate the efficiency of the alternating proximal gradient method and the accleration technique. Especially for real data tests, the accelerated method reveals high superiority to state-of-the-art algorithms in speed with comparable solution qualities.

  10. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    Science.gov (United States)

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-01

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. The observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.

  11. Amplitude dependent orbital period in alternating gradient accelerators

    OpenAIRE

    S. Machida; Kelliher, D. J.; Edmonds, C. S.; Kirkman, I. W.; Berg, J. S.; Jones, J. K.; Muratori, B. D.; Garland, J. M.

    2016-01-01

    Orbital period in a ring accelerator and time of flight in a linear accelerator depend on the amplitude of betatron oscillations. The variation is negligible in ordinary particle accelerators with relatively small beam emittance. In an accelerator for large emittance beams like muons and unstable nuclei, however, this effect cannot be ignored. We measured orbital period in a linear non-scaling fixed field alternating gradient (FFAG) accelerator, which is a candidate for muon acceleration, and...

  12. Transport of polar molecules by an alternating gradient guide

    OpenAIRE

    Wall, T. E.; Armitage, S; Hudson, J. J.; Sauer, B. E.; Dyne, J. M.; Hinds, E. A.; Tarbutt, M.R.

    2009-01-01

    An alternating gradient electric guide provides a way to transport a wide variety of polar molecules, including those in high-field seeking states. We investigate the motion of polar molecules in such a guide by measuring the transmission of CaF molecules in their high-field seeking ground state, with the guide operating at a variety of switching frequencies and voltages. We model the guide using analytical and numerical techniques and compare the predictions of these models to the experiment...

  13. Amplitude-dependent orbital period in alternating gradient accelerators

    Science.gov (United States)

    Machida, S.; Kelliher, D. J.; Edmonds, C. S.; Kirkman, I. W.; Berg, J. S.; Jones, J. K.; Muratori, B. D.; Garland, J. M.

    2016-03-01

    Orbital period in a ring accelerator and time of flight in a linear accelerator depend on the amplitude of betatron oscillations. The variation is negligible in ordinary particle accelerators with relatively small beam emittance. In an accelerator for large emittance beams like muons and unstable nuclei, however, this effect cannot be ignored. We measured orbital period in a linear non-scaling fixed-field alternating-gradient accelerator, which is a candidate for muon acceleration, and compared it with the theoretical prediction. The good agreement between them gives important ground for the design of particle accelerators for a new generation of particle and nuclear physics experiments.

  14. Amplitude dependent orbital period in alternating gradient accelerators

    CERN Document Server

    Machida, S; Edmonds, C S; Kirkman, I W; Berg, J S; Jones, J K; Muratori, B D; Garland, J M

    2016-01-01

    Orbital period in a ring accelerator and time of flight in a linear accelerator depend on the amplitude of betatron oscillations. The variation is negligible in ordinary particle accelerators with relatively small beam emittance. In an accelerator for large emittance beams like muons and unstable nuclei, however, this effect cannot be ignored. We measured orbital period in a linear non-scaling fixed field alternating gradient (FFAG) accelerator, which is a candidate for muon acceleration, and compared with the theoretical prediction. The good agreement between them gives important ground for the design of particle accelerators for a new generation of particle and nuclear physics experiments.

  15. Pulsed spallation neutron source with an induction LINAC and a fixed-field alternating-gradient accelerator

    International Nuclear Information System (INIS)

    The paper describes an accelerator scenario of a Pulsed Spallation Neutron Source made of an Induction Linac injecting into a Fixed-Field Alternating-Gradient Accelerator (FFAG). The motivations underlying the proposal deal with the concern of removing technical risks peculiar to other scenarios involving RF Linacs, Synchrotrons and Accumulator Rings, which originate, for example, from the need of developing intense negative-ion sources and of multi-turn injection into the Compressor Rings. The system proposed here makes use of a positive-ion source of very short pulse duration, and of single-turn transfer into the circular accelerator. (author) 2 figs., 2 tabs., 16 refs

  16. Combined alternating gradient force magnetometer and susceptometer system.

    Science.gov (United States)

    Pérez, M; Ranchal, R; de Mendizábal Vázquez, I; Cobos, P; Aroca, C

    2015-01-01

    We report the design, fabrication, and characterization of a new system that combines the performances of two different types of magnetic characterization systems, Alternating Gradient Force Magnetometers (AGFM) and susceptometers. The flexibility of our system is demonstrated by its capability to be used as any of them, AGFM or susceptometer, without any modification in the experimental set-up because of the electronics we have developed. Our system has a limit of sensitivity lower than 5 × 10(-7) emu. Moreover, its main advantage is demonstrated by the possibility of measuring small quantities of materials under DC or AC magnetic fields that cannot properly be measured with a commercial vibrating sample magnetometers or AGFM. PMID:25638125

  17. Combined alternating gradient force magnetometer and susceptometer system

    International Nuclear Information System (INIS)

    We report the design, fabrication, and characterization of a new system that combines the performances of two different types of magnetic characterization systems, Alternating Gradient Force Magnetometers (AGFM) and susceptometers. The flexibility of our system is demonstrated by its capability to be used as any of them, AGFM or susceptometer, without any modification in the experimental set-up because of the electronics we have developed. Our system has a limit of sensitivity lower than 5 × 10−7 emu. Moreover, its main advantage is demonstrated by the possibility of measuring small quantities of materials under DC or AC magnetic fields that cannot properly be measured with a commercial vibrating sample magnetometers or AGFM

  18. Combined alternating gradient force magnetometer and susceptometer system

    Energy Technology Data Exchange (ETDEWEB)

    Pérez, M.; Mendizábal Vázquez, I. de; Aroca, C. [Dpto. Física Aplicada, E.T.S.I. Telecomunicación, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, Madrid 28040 (Spain); Ranchal, R. [Dpto. Física de Materiales, Facultad Ciencias Físicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, Madrid 28040 (Spain); Cobos, P. [ISOM, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, Madrid 28040 (Spain)

    2015-01-15

    We report the design, fabrication, and characterization of a new system that combines the performances of two different types of magnetic characterization systems, Alternating Gradient Force Magnetometers (AGFM) and susceptometers. The flexibility of our system is demonstrated by its capability to be used as any of them, AGFM or susceptometer, without any modification in the experimental set-up because of the electronics we have developed. Our system has a limit of sensitivity lower than 5 × 10{sup −7} emu. Moreover, its main advantage is demonstrated by the possibility of measuring small quantities of materials under DC or AC magnetic fields that cannot properly be measured with a commercial vibrating sample magnetometers or AGFM.

  19. Alternate gradient focusing and deceleration of a molecular beam

    International Nuclear Information System (INIS)

    Neutral dipolar molecules can be decelerated and trapped using time-varying inhomogeneous electric fields. This has been demonstrated only for molecules in low-field seeking states, but can, in principle, be performed on molecules in high-field seeking states as well. Transverse stability is then much more difficult to obtain, however, since molecules in high-field seeking states always experience a force towards the electrodes. Here we demonstrate that an array of dipole lenses in alternate gradient configuration can be used to maintain transverse stability. A pulsed beam of metastable CO in high-field seeking states is accelerated from 275 to 289 m/s as well as decelerated from 275 to 260 m/s

  20. Alternating Gradient Focusing and Deceleration of Polar Molecules

    CERN Document Server

    Bethlem, H L; Küpper, J; Carty, D; Wohlfart, K; Hinds, E A; Meijer, G; Bethlem, Hendrick L.; Kuepper, Jochen; Carty, David; Wohlfart, Kirstin; Meijer, Gerard

    2006-01-01

    Beams of polar molecules can be focused using an array of electrostatic lenses in alternating gradient (AG) configuration. They can also be accelerated or decelerated by applying an appropriate high voltage switching sequence to the lenses. AG focusing is applicable to molecules in both low-field and high-field-seeking states and is particularly well suited to the problem of decelerating heavy molecules and those in their ground rotational state. We describe the principles of AG deceleration and set out criteria to be followed in decelerator design, construction and operation. We calculate the longitudinal and transverse focusing properties of a decelerator, and exemplify this by 2D-imaging studies of a decelerated beam of metastable CO molecules.

  1. Transport of polar molecules by an alternating gradient guide

    CERN Document Server

    Wall, T E; Hudson, J J; Sauer, B E; Dyne, J M; Hinds, E A; Tarbutt, M R

    2009-01-01

    An alternating gradient electric guide provides a way to transport a wide variety of polar molecules, including those in high-field seeking states. We investigate the motion of polar molecules in such a guide by measuring the transmission of CaF molecules in their high-field seeking ground state, with the guide operating at a variety of switching frequencies and voltages. We model the guide using analytical and numerical techniques and compare the predictions of these models to the experimental results and to one another. The analytical results are approximate, but provide simple and useful estimates for the maximum phase-space acceptance of the guide and for the switching frequency required. The numerical methods provide more accurate results over the full range of switching frequencies. Our investigation reveals a novel mode of guiding that uses static fields alone to transport high-field seeking molecules. We show that the maximum possible transmission requires accurate alignment within the guide and betwe...

  2. Study of Temperature Gradient in Burning of Alternative Engine Fuels

    Directory of Open Access Journals (Sweden)

    M. S. Assad

    2008-01-01

    Full Text Available The paper gives an approximate method for calculation of the temperature at a final stage of fuel-air mixture burning in a closed vessel that is a combustion chamber of the internal combustion engine (ICE. The paper contains calculation of temperature values for various fuel-air mixtures, shows nature of temperature changes and presents analysis of combustion product temperature behaviour modification and analyzed the behaviour in accordance with an initial pressure in the chamber. The paper reveals the fact that a combustion temperature is increasing for all mixtures when an initial pressure in combustion chamber is increased. The hydrogen-air mixture has the highest combustion temperature among investigated mixtures and products of propane conversion have the lowest one.The Maxe-effect has been investigated in combustion of hydrogen-air mixture and design formulaes have been obtained. Calculation of temperature difference of the first and last portions of combustion products has been made with due account of the Maxe-effect.The proposed approximate method for calculation of temperatures indices in the various zones of combustion chamber in view of the Mach effect makes it possible to forecast thermodynamic nature of combustion process while using alternative engine fuels for internal combustion engine.

  3. Quantitative analysis by in situ synchrotron X-ray radiography of the evolution of the mushy zone in a fixed temperature gradient

    Science.gov (United States)

    Salloum-Abou-Jaoude, G.; Reinhart, G.; Combeau, H.; Založnik, M.; Lafford, T. A.; Nguyen-Thi, H.

    2015-02-01

    This paper deals with a series of experiments dedicated to the analysis of the time evolution of a mushy zone in a fixed temperature gradient, carried out on the BM05 beamline at the European Synchrotron Radiation Facility (ESRF) on Al-Cu alloy. Because most of phenomena involved in this evolution are dynamic, in situ and real time investigation is essential for conducting a thorough analysis as a function of time. Synchrotron X-ray radiography is a non-invasive visualization technique, perfectly suited to such a study since it is able to reveal the microstructural changes of the mushy zone during the holding stage. In addition, we extended our analysis by performing advanced image processing of synchrotron X-ray radiographs to characterize the solute distribution in the liquid phase. These measurements gave us crucial information for understanding the competition between the diffusion processes in the bulk and the mushy zone. Moreover, combining these data with mass balance equations at the two boundaries of the mushy zone enables us to demonstrate the major role of solute diffusion in the dynamics of the mushy zone, from the early instants to the final state of the holding stage.

  4. Adiabatic Rormation of a Matched-beam Distribution for an Alternating-gradient Quadrupole Lattice

    International Nuclear Information System (INIS)

    The formation of a quasiequilibrium beam distribution matched to an alternating-gradient quadrupole focusing lattice by means of the adiabatic turn-on of the oscillating focusing field is studied numerically using particle-in-cell simulations. Quiescent beam propagation over several hundred lattice periods is demonstrated for a broad range of beam intensities and vacuum phase advances describing the strength of the oscillating focusing field. Properties of the matched-beam distribution are investigated. In particular, self-similar evolution of the beam density profile is observed over a wide range of system parameters. The numerical simulations are performed using the WARP particle-in-cell code.

  5. Electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole channel

    International Nuclear Information System (INIS)

    This work studies the electron-beam envelopes and matching for a combined wiggler and alternating-gradient quadrupole field for a free-electron laser (FEL) that will be operated in the VUV or XUV wavelength region. The quadrupole field is assumed to vary continuously along the symmetry axis. The linearized equations of electron motion are solved analytically by using the two-scale perturbation method for a plane polarized wiggler. The electron-beam envelopes and the envelope equations, as well as the matching conditions in phase space, are obtained from the electron trajectories. A comparison with the numerical solution is presented

  6. Fixed Field Alternating Gradient (FFAG)accelerators and their medical application in proton therapy

    International Nuclear Information System (INIS)

    Radiotherapy uses particle beams to irradiate and kill cancer tumors while sparing healthy tissues. Bragg peak shape of the proton energy loss in matter allows a ballistic improvement of the dose deposition compared with X rays. Thus, the irradiated volume can be precisely adjusted to the tumour. This thesis, in the frame of the RACCAM project, aims to the study and the design of a proton therapy installation based on a fixed field alternating gradient (FFAG) accelerator in order to build a spiral sector FFAG magnet for validation. First, we present proton therapy to define medical specifications leading to the technical specifications of a proton therapy installation. Secondly, we introduce FFAG accelerators through their past and on-going projects which are on their way around the world before developing the beam dynamic theories in the case of invariant focusing optics (scaling FFAG). We describe modelling and simulation tools developed to study the dynamics in a spiral scaling FFAG accelerator. Then we explain the spiral optic parameter search which has leaded to the construction of a magnet prototype. Finally, we describe the RACCAM project proton therapy installation starting from the injector cyclotron and ending with the extraction system. (author)

  7. Dynamics of Particles in Non Scaling Fixed Field Alternating Gradient Accelerators

    Directory of Open Access Journals (Sweden)

    Jones J. K.

    2010-01-01

    Full Text Available Non scaling Fixed-Field Alternating Gradient (FFAG accelerators have an unprece- dented potential for muon acceleration, as well as for medical purposes based on car- bon and proton hadron therapy. They also represent a possible active element for an Accelerator Driven Subcritical Reactor (ADSR. Starting from first principle the Hamil- tonian formalism for the description of the dynamics of particles in non-scaling FFAG machines has been developed. The stationary reference (closed orbit has been found within the Hamiltonian framework. The dependence of the path length on the energy deviation has been described in terms of higher order dispersion functions. The latter have been used subsequently to specify the longitudinal part of the Hamiltonian. It has been shown that higher order phase slip coefficients should be taken into account to adequately describe the acceleration in non-scaling FFAG accelerators. A complete theory of the fast (serpentine acceleration in non-scaling FFAGs has been developed. An example of the theory is presented for the parameters of the Electron Machine with Many Applications (EMMA, a prototype electron non-scaling FFAG to be hosted at Daresbury Laboratory.

  8. Dynamics of Particles in Non Scaling Fixed Field Alternating Gradient Accelerators

    Directory of Open Access Journals (Sweden)

    Tzenov S. I.

    2010-01-01

    Full Text Available Non scaling Fixed-Field Alternating Gradient (FFAG accelerators have an unprecedented potential for muon acceleration, as well as for medical purposes based on carbon and proton hadron therapy. They also represent a possible active element for an Accelerator Driven Subcritical Reactor (ADSR. Starting from first principle the Hamiltonian formalism for the description of the dynamics of particles in non-scaling FFAG machines has been developed. The stationary reference (closed orbit has been found within the Hamiltonian framework. The dependence of the path length on the energy deviation has been described in terms of higher order dispersion functions. The latter have been used subsequently to specify the longitudinal part of the Hamiltonian. It has been shown that higher order phase slip coefficients should be taken into account to adequately describe the acceleration in non-scaling FFAG accelerators. A complete theory of the fast (serpentine acceleration in non-scaling FFAGs has been developed. An example of the theory is presented for the parameters of the Electron Machine with Many Applications (EMMA, a prototype electron non-scaling FFAG to be hosted at Daresbury Laboratory.

  9. Space-charge calculations in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Machida, S.

    1993-05-01

    One obvious bottleneck of achieving high luminosity in hadron colliders, such as the Superconducting Super Collider (SSC), is the beam emittance growth, due to space-charge effects in low energy injector synchrotrons. Although space-charge effects have been recognized since the alternating-gradient synchrotron was invented, and the Laslett tune shift usually calculated to quantify these effects, our understanding of the effects is limited, especially when the Laslett tune shift becomes a large fraction of the integer. Using the Simpsons tracking code, which we developed to study emittance preservation issues in proton synchrotrons, we investigated space-charge effects in the SSC Low Energy Booster (LEB). We observed detailed dependence on parameters such as beam intensity, initial emittance, injection energy, lattice function, and longitudinal motion. A summary of those findings, as well as the tracking technique we developed for the study, are presented.

  10. Applications of first order matricial theory to the calculation of storage ring designed for producing synchrotron radiation

    International Nuclear Information System (INIS)

    A review of first order matrix theory (linear approximation) used for calculating component elements of a particle accelerator employing the synchrotron principle of alternated gradient, is presented. Based on this theory, criteria for dimensioning synchrotron designed, exclusively for producing electromagnetic radiation, are established. The problem to find out optimum disposition of elements (straight line sections, quadrupolar magnetic lens, etc.) which take advantages of deflector magnets of the DCI synchrotron (Orsay Linear Accelerator Laboratory, French) aiming to construct a synchrotron designed to operate as electromagnetic radiation source, is solved. (M.C.K.)

  11. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy?

    International Nuclear Information System (INIS)

    Synchrotron Radiation induced X-ray micro Fluorescence analysis (μ-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed

  12. ERL with non-scaling fixed field alternating gradient lattice for eRHIC

    Energy Technology Data Exchange (ETDEWEB)

    Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brooks, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hao, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. N. [Brookhaven National Lab. (BNL), Upton, NY (United States); Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    The proposed eRHIC electron-hadron collider uses a "non-scaling FFAG" (NS-FFAG) lattice to recirculate 16 turns of different energy through just two beam lines located in the RHIC tunnel. This paper presents lattices for these two FFAGs that are optimized for low magnet field and to minimize total synchrotron radiation across the energy range. The higher number of recirculations in the FFAG allows a shorter linac (1.322GeV) to be used, drastically reducing cost, while still achieving a 21.2 GeV maximum energy to collide with one of the existing RHIC hadron rings at up to 250GeV. eRHIC uses many cost-saving measures in addition to the FFAG: the linac operates in energy recovery mode, so the beams also decelerate via the same FFAG loops and energy is recovered from the interacted beam. All magnets will be constructed from NdFeB permanent magnet material, meaning chillers and large magnet power supplies are not needed. This paper also describes a small prototype ERL-FFAG accelerator that will test all of these technologies in combination to reduce technical risk for eRHIC.

  13. Broadband abnormal reflection based on a metal-backed gradient index liquid slab: an alternative to metasurfaces

    International Nuclear Information System (INIS)

    We present an alternative method of introducing phase discontinuity, and demonstrate the design, fabrication and characterization of a thin abnormal-reflection slab using compound liquids in a sterolithography container. Normally incident electromagnetic waves penetrate into the gradient index slab and then are reflected by the metallic backing. Because gradient phase difference is produced on the thin slab surface, the propagation direction of the reflected beam is modulated. To obtain the phase gradient, we mix two liquids with different permittivities, which can realize a refraction index ranging from 1.6 ∼ 6.5. To load and separate liquids with different refractive indexes, the sterolithography technique is used to fabricate the thin-walled container using photosensitive resin. We designed and fabricated a sample which has a 30° abnormal reflection angle under normal incidence with a thickness of 1/7 of the wavelength under 8.0 GHz. Broadband far-field patterns, as well as a near-field map at the working frequency, were simulated, theoretically discussed and experimentally measured. The results verify abnormal reflection of the sample. Compared with abnormal-reflection metasurfaces, the thin slab has a wider bandwidth (the relative bandwidth is 50%) and weaker polarization dependence. (paper)

  14. A novel high-temperature furnace for combined in situ synchrotron X-ray diffraction and infrared thermal imaging to investigate the effects of thermal gradients upon the structure of ceramic materials

    International Nuclear Information System (INIS)

    A combined X-ray diffraction and thermal imaging technique is described to investigate the effect of thermal gradients on high-temperature composite materials. A new technique combining in situ X-ray diffraction using synchrotron radiation and infrared thermal imaging is reported. The technique enables the application, generation and measurement of significant thermal gradients, and furthermore allows the direct spatial correlation of thermal and crystallographic measurements. The design and implementation of a novel furnace enabling the simultaneous thermal and X-ray measurements is described. The technique is expected to have wide applicability in material science and engineering; here it has been applied to the study of solid oxide fuel cells at high temperature

  15. The PyZgoubi framework and the simulation of dynamic aperture in fixed-field alternating-gradient accelerators

    International Nuclear Information System (INIS)

    We present PyZgoubi, a framework that has been developed based on the tracking engine Zgoubi to model, optimise and visualise the dynamics in particle accelerators, especially fixed-field alternating-gradient (FFAG) accelerators. We show that PyZgoubi abstracts Zgoubi by wrapping it in an easy-to-use Python framework in order to allow simple construction, parameterisation, visualisation and optimisation of FFAG accelerator lattices. Its object oriented design gives it the flexibility and extensibility required for current novel FFAG design. We apply PyZgoubi to two example FFAGs; this includes determining the dynamic aperture of the PAMELA medical FFAG in the presence of magnet misalignments, and illustrating how PyZgoubi may be used to optimise FFAGs. We also discuss a robust definition of dynamic aperture in an FFAG and show its implementation in PyZgoubi

  16. The PyZgoubi framework and the simulation of dynamic aperture in fixed-field alternating-gradient accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Tygier, S., E-mail: sam.tygier@hep.manchester.ac.uk [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Appleby, R.B., E-mail: robert.appleby@manchester.ac.uk [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Garland, J.M. [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Hock, K. [University of Liverpool (United Kingdom); Owen, H. [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Kelliher, D.J.; Sheehy, S.L. [STFC Rutherford Appleton Laboratory (United Kingdom)

    2015-03-01

    We present PyZgoubi, a framework that has been developed based on the tracking engine Zgoubi to model, optimise and visualise the dynamics in particle accelerators, especially fixed-field alternating-gradient (FFAG) accelerators. We show that PyZgoubi abstracts Zgoubi by wrapping it in an easy-to-use Python framework in order to allow simple construction, parameterisation, visualisation and optimisation of FFAG accelerator lattices. Its object oriented design gives it the flexibility and extensibility required for current novel FFAG design. We apply PyZgoubi to two example FFAGs; this includes determining the dynamic aperture of the PAMELA medical FFAG in the presence of magnet misalignments, and illustrating how PyZgoubi may be used to optimise FFAGs. We also discuss a robust definition of dynamic aperture in an FFAG and show its implementation in PyZgoubi.

  17. Synchrotron radiation

    International Nuclear Information System (INIS)

    The paper on Synchrotron Radiation contains the appendix to the Daresbury Annual Report 1987/88. The appendix is mainly devoted to the scientific progress reports on the work at the Synchrotron Radiation Source in 1987/8. The parameters of the Experimental Stations and the index to the Scientific Reports are also included in the appendix. (U.K.)

  18. Synchrotron light

    International Nuclear Information System (INIS)

    'Synchrotron Light' is an interactive and detailed introduction to the physics and technology of the generation of coherent radiation from accelerators as well as to its widespread high-tech applications in science, medicine and engineering. The topics covered are the interaction of light and matter, the technology of synchrotron light sources, spectroscopy, imaging, scattering and diffraction of X-rays, and applications to materials science, biology, biochemistry, medicine, chemistry, food and pharmaceutical technology. All synchrotron light facilities are introduced with their home-page addresses. 'Synchrotron Light' provides an instructive and comprehensive multimedia learning tool for students, experienced practitioners and novices wishing to apply synchrotron radiation in their future work. Its multiple-entry points permit an easy exploration of the CD-Rom according to the users knowledge and interest. 2-D and 3-D animations and virtual reconstruction with computer-generated images guide visitors into the scientific and technical world of a synchrotron and into the applications of synchrotron radiation. This bilingual (English and French) CD-Rom can be used for self-teaching and in courses at various levels in physics, chemistry, engineering, and biology. (author)

  19. 50 Years of synchrotrons Adams' Memorial lecture

    CERN Document Server

    Lawson, J D; CERN. Geneva

    1996-01-01

    Fifty years ago Frank Goward of the Atomic Energy Research Establishment Group at Malvern converted a small American betatron to make the worldÕs first synchrotron. At the same time Marcus Oliphant was planning to build at Birmingham a large proton machine with a ring magnet and variable magnetic field. Ideas for this had come to him during night-shifts tending the electromagnetic separators at Oak Ridge during the war. Some seven years later, in 1953, a group gathered together in Geneva to build the PS. A major contributor to the design work which had made this possible was John Adams. An account of some of the achievements in these eventful years will be presented. CERN has built nine synchrotrons/colliders and two temporary test rings. Eight machines are still running. The review will start with the PS, the first proton synchrotron based on the alternating gradient principle invented in 1952 at BNL. The design work of the PS team, under the enlightened leadership of J.B. Adams, and the construction of the...

  20. Synchrotron radiation

    International Nuclear Information System (INIS)

    A detailed account of the research work associated with the Synchrotron Radiation Source at Daresbury Laboratory, United Kingdom, in 1984/85, is presented in the Appendix to the Laboratory's Annual Report. (U.K.)

  1. Synchrotron radiation

    International Nuclear Information System (INIS)

    Synchrotron radiation has had a revolutionary effect on a broad range of scientific studies, from physics, chemistry and metallurgy to biology, medicine and geoscience. The situation during the last decade has been one of very rapid growth, there is a great vitality to the field and a capability has been given to a very broad range of scientific disciplines which was undreamt of just a decade or so ago. In this paper, the authors discuss some of the properties of synchrotron radiation that makes it so interesting and something of the sources in existence today including the National Synchrotron Light Source (NSLS). The NSLS is one of the new facilities built specifically for synchrotron radiation research and the model that was developed there for involvement of the scientific community is a good one which provides some good lessons for these facilities and others

  2. Synchrotron radiation

    International Nuclear Information System (INIS)

    A report is given on the work involving the Synchrotron Radiation Division of the Daresbury Laboratory during the period January 1981 - March 1982. Development of the source, beamlines and experimental stations is described. Progress reports from individual investigators are presented which reveal the general diversity and interdisciplinary nature of the research which benefits from access to synchrotron radiation and the associated facilities. Information is given on the organisation of the Division and publications written by the staff are listed. (U.K.)

  3. Synchrotron radiation

    International Nuclear Information System (INIS)

    The paper on synchrotron radiation is the appendix to the Daresbury (United Kingdom) annual report, 1985/86. The bulk of the volume is made up of the progress reports for the work carried out during the year under review using the Synchrotron Radiation Source (SRS) at Daresbury. The Appendix also contains: the scientific programmes at the the SRS, progress on beamlines, instrumentation and computing developments, and activities connected with accelerator development. (U.K.)

  4. 50 years of synchrotrons. Early synchrotrons in Britain, and early work for CERN. - The CERN synchrotrons. Lectures

    International Nuclear Information System (INIS)

    In the first report, 'Early synchrotrons in Britain, and early work for CERN', John Lawson gives an extended account of the material presented at the John Adams lecture, and at the same time a revised and shortened version of RAL report 97-011, which contains fuller archival references and notes. During the period covered by this report there was extensive work in Russia, where the principle of phase stability had been discovered in 1944 by Veksler. Unfortunately, all experimental work was kept secret until Veksler's talk at the first 'Atoms for Peace' conference at Geneva in August 1955. In the second lecture, 'The CERN Synchrotrons', Giorgio Brianti outlines the history of alternating-gradient synchrotrons from 1953/54 until today. In preparing this lecture he was confronted with a vast amount of material, while the time at his disposal was not even one minute per year, implying a time compression factor close to one million. Therefore, he had to exercise drastic choices, which led him to concentrate on CERN hadron synchrotrons and colliders and leave aside the Large Electron-Positron storage ring (LEP). Indeed, LEP was the subject of the John Adams Memorial Lecture in 1990, and it may be treated again in the future in connection with its energy upgrade. Even with these severe limitations, it was impossible to do justice to the number and variety of events and to the ingenuity of the people who have carved the history of CERN and of particle physics on the magnets, radiofrequency cavities, vacuum etc., and on the record performance of our machines. (orig./WL)

  5. Characterization techniques for fixed-field alternating gradient accelerators and beam studies using the KURRI 150 MeV proton FFAG

    CERN Document Server

    Sheehy, S L; Machida, S; Rogers, C; Prior, C R; Volat, L; Tahar, M Haj; Ishi, Y; Kuriyama, Y; Sakamoto, M; Uesugi, T; Mori, Y

    2015-01-01

    In this paper we describe the methods and tools used to characterize a 150 MeV proton scaling Fixed Field Alternating Gradient (FFAG) accelerator at Kyoto University Research Reactor Institute. Many of the techniques used are unique to this class of machine and are thus of relevance to any future FFAG accelerator. For the first time we detail systematic studies undertaken to improve the beam quality of the FFAG. The control of beam quality in this manner is crucial to demonstrating high power operation of FFAG accelerators in future.

  6. The influence of high thermal gradient casting, hot isostatic pressing and alternate heat treatment on the structure and properties of a single crystal nickel base superalloy

    Science.gov (United States)

    Fritzemeier, L. G.

    1988-01-01

    A development program has been conducted to improve the cyclic properties of the PWA 1480 single-crystal superalloy by reducing or entirely eliminating casting porosity at fatigue-initiation sites, through the use of improved casting process parameters and HIPing; potential mechanical property improvements in a high-pressure hydrogen environment were also sought in alternatives to the standard coating and heat-treatment cycle. High thermal gradient casting was found to yield a reduction in overall casting porosity density and pore sizes. The most dramatic mechanical property improvement resulted from HIPing.

  7. Characterization techniques for fixed-field alternating gradient accelerators and beam studies using the KURRI 150 MeV proton FFAG

    Science.gov (United States)

    Sheehy, S. L.; Kelliher, D. J.; Machida, S.; Rogers, C.; Prior, C. R.; Volat, L.; Haj Tahar, M.; Ishi, Y.; Kuriyama, Y.; Sakamoto, M.; Uesugi, T.; Mori, Y.

    2016-07-01

    In this paper we describe the methods and tools used to characterize a 150 MeV proton scaling fixed field alternating gradient (FFAG) accelerator at Kyoto University Research Reactor Institute. Many of the techniques used are unique to this class of machine and are thus of relevance to any future FFAG accelerator. For the first time we detail systematic studies undertaken to improve the beam quality of the FFAG. The control of beam quality in this manner is crucial to demonstrating high power operation of FFAG accelerators in future.

  8. Synchrotron radiation

    International Nuclear Information System (INIS)

    This report details the activities in synchrotron radiation and related areas at Daresbury Laboratory during 1989/90. The number and scope of the scientific reports submitted by external users and in-house staff is a reflection of the large amount of scheduled beamtime and high operating efficiency achieved at the Synchrotron Radiation Source (SRS) during the past year. Over 4000 hours of user beam were available, equivalent to about 80% of the total scheduled time. Many of the reports collected here illustrate the increasing technical complexity of the experiments now being carried out at Daresbury. Provision of the appropriate technical and scientific infrastructure and support is a continuing challenge. The development of the Materials Science Laboratory together with the existing Biological Support Laboratory will extend the range of experiments which can be carried out on the SRS. This will particularly facilitate work in which the sample must be prepared or characterised immediately before or during an experiment. The year 1989/90 has also seen a substantial upgrade of several stations, especially in the area of x-ray optics. Many of the advantages of the High Brightness Lattice can only be exploited effectively with the use of focusing optics. As the performance of these stations improves, the range of experiments which are feasible on the SRS will be extended significantly. (author)

  9. Design Study of the Large Hadron Electron Collider and a Rapid Cycling Synchrotron as Alternative to the PS Booster Upgrade at CERN

    OpenAIRE

    Fitterer, Miriam

    2013-01-01

    To further extend the discovery potential of the Large Hadron Collider (LHC), a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors. Furthermore it has been suggested to built a new electron accelerator in order to allow for deep inelastic lepton-nucleon scattering at the LHC, referred to as Large Hadron Electron Collider (LHeC). In this thesis design options for a new LHC injector - a Rapid Cycling Synchrotron - and an electron accelerator for the LHeC are presented.

  10. Developing alternative indices of reproductive potential for use in fisheries management : Case studies for stocks spanning an information gradient

    DEFF Research Database (Denmark)

    Marshall, C.T.; O'Brien, L.; Tomkiewicz, Jonna; Marteinsdottir, G.; Morgan, M.J.; Saborido-Rey, F.; Köster, Fritz; Blanchard, J.L.; Secor, D.H.; Kraus, Gerd; Wright, P.; Mukhina, N.V.; Björnsson, H.

    2003-01-01

    sufficient data to reconstruct a time series of total eggproduction (TEP), whereas, the remaining stocks were limited to estimating proxies for stockreproductive potential. For some of the case studies the alternative indices explained a higheramount of recruitment variation than did SSB. Other case studies...... provided evidence that char-acteristics of the spawning stock, e.g. age diversity and female-only SSB, influence recruitmentin ways that are not properly accounted for by using SSB as the sole index of reproductivepotential. This is further evidence that the assumption of proportionality between SSB andTEP...... is invalid. The data-rich stocks showed the relationship between SSB and TEP to bevariable and characterized by distinct time trends. This variability will impact the ability ofbiomass-based reference points to conserve reproductive potential. Consequently, managementprotocols should be adapted to...

  11. Synchrotron radiation

    International Nuclear Information System (INIS)

    Synchrotron radiation (SR) from the bending magnet of a circular electron (positron) accelerator is a brilliant source in the vacuum ultraviolet, soft- and hard-x ray regions. First the characteristics of the bending SR are delete discussed. Though the brilliance of SR was improved dramatically in the last decade, neither bending, wiggler SR nor undulator SR is coherent. Coherent far infrared radiation in the mm wavelength region has recently been observed from a short electron bunch (∼ 2.5 mm long) in a bending magnet connected to a linac at Tohoku University. Coherent radiation due to higher harmonics generation by laser excitation of electron bunches in an undulator is then described. Finally a free electron laser (FEL) using optical klystron in a storage ring is reviewed. (author)

  12. Synchrotron radiation

    International Nuclear Information System (INIS)

    Work at the Daresbury SRS has of necessity been interrupted this year (1991/92) due to the incorporation of Wiggler II. However, considerable beamtime was awarded before the shutdown and the major part of this appendix is concerned with the progress reports of the research undertaken then. The reports have been organised under the following broad headings: Molecular Science (19 papers), Surface and Materials Science (169 papers), Biological Science (85 papers), Instrumental and Technique Developments (13 papers) and Accelerator Physics (3 papers). It is hoped that in time the number of contributions on accelerator physics will grow to reflect the in-house activity on, for example, accelerator improvement and design. The research reports are preceded by the Annual Report of the Synchrotron Radiation Facilities Committee, which outlines the research highlights identified by that Committee (also included are details of the current membership of the SRFC and the chairmen of the Beamtime Allocation Panels). Following the reports are the specifications for the beamlines and stations. This year Section 3 contains 289 reports (nearly 100 more than last year) and the number of publications, generated by scientists and engineers who have used or are associated with Daresbury Laboratory facilities, has topped 500 for the first time. (author)

  13. Design study of the large hadron electron collider and a rapid cycling synchrotron as alternative to the PS booster upgrade at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Fitterer, Miriam

    2013-02-22

    With the Large Hadron Collider (LHC) the exploration of particle physics at center of mass energies at the TeV scale has begun. To extend the discovery potential of the LHC, a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors - the chain of accelerators preparing the beam for the LHC. One of the injectors - the second one in the chain - is the Proton Synchrotron (PS) Booster. Its performance is currently limited by the space-charge effect, which is the effect of the electromagnetic field of the particle beam on itself. This effect becomes weaker with higher energy, and therefore an energy upgrade of the PS Booster to 2 GeV maximum beam energy is foreseen. As the PS Booster is with its 40 years already an old machine, the construction of a new accelerator, a Rapid Cycling Synchrotron (RCS), to replace the PS Booster has been proposed. In this thesis different options for the beam guidance in the RCS - referred to as lattice and optics - are studied, followed by a more general comparison of different lattices and optics and their performance under consideration of the space-charge effect. To further complement the LHC physics program, also the possibility of deep inelastic lepton-nucleon scattering at the LHC has been suggested, referred to as Large Hadron Electron Collider (LHeC). In this case the proton beam of the LHC collides with the electron beam, which is accelerated in a separate newly built machine. Two options are considered as electron accelerator: a new energy recovery linac - the Linac-Ring option - and the installation of an electron ring in the existing LHC tunnel - the Ring-Ring option. One of the main challenges of the Ring-Ring option is the integration of the electron ring in the current LHC tunnel. A layout, lattice and optics of the electron accelerator is developed in this thesis, which meets the requirements with regard to integration and reaches the beam parameters demanded by the particle physics experiments.

  14. Design study of the large hadron electron collider and a rapid cycling synchrotron as alternative to the PS booster upgrade at CERN

    International Nuclear Information System (INIS)

    With the Large Hadron Collider (LHC) the exploration of particle physics at center of mass energies at the TeV scale has begun. To extend the discovery potential of the LHC, a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors - the chain of accelerators preparing the beam for the LHC. One of the injectors - the second one in the chain - is the Proton Synchrotron (PS) Booster. Its performance is currently limited by the space-charge effect, which is the effect of the electromagnetic field of the particle beam on itself. This effect becomes weaker with higher energy, and therefore an energy upgrade of the PS Booster to 2 GeV maximum beam energy is foreseen. As the PS Booster is with its 40 years already an old machine, the construction of a new accelerator, a Rapid Cycling Synchrotron (RCS), to replace the PS Booster has been proposed. In this thesis different options for the beam guidance in the RCS - referred to as lattice and optics - are studied, followed by a more general comparison of different lattices and optics and their performance under consideration of the space-charge effect. To further complement the LHC physics program, also the possibility of deep inelastic lepton-nucleon scattering at the LHC has been suggested, referred to as Large Hadron Electron Collider (LHeC). In this case the proton beam of the LHC collides with the electron beam, which is accelerated in a separate newly built machine. Two options are considered as electron accelerator: a new energy recovery linac - the Linac-Ring option - and the installation of an electron ring in the existing LHC tunnel - the Ring-Ring option. One of the main challenges of the Ring-Ring option is the integration of the electron ring in the current LHC tunnel. A layout, lattice and optics of the electron accelerator is developed in this thesis, which meets the requirements with regard to integration and reaches the beam parameters demanded by the particle physics experiments.

  15. Heterogeneous engineered cartilage growth results from gradients of media-supplemented active TGF-β and is ameliorated by the alternative supplementation of latent TGF-β.

    Science.gov (United States)

    Albro, Michael B; Nims, Robert J; Durney, Krista M; Cigan, Alexander D; Shim, Jay J; Vunjak-Novakovic, Gordana; Hung, Clark T; Ateshian, Gerard A

    2016-01-01

    Transforming growth factor beta (TGF-β) has become one of the most widely utilized mediators of engineered cartilage growth. It is typically exogenously supplemented in the culture medium in its active form, with the expectation that it will readily transport into tissue constructs through passive diffusion and influence cellular biosynthesis uniformly. The results of this investigation advance three novel concepts regarding the role of TGF-β in cartilage tissue engineering that have important implications for tissue development. First, through the experimental and computational analysis of TGF-β concentration distributions, we demonstrate that, contrary to conventional expectations, media-supplemented exogenous active TGF-β exhibits a pronounced concentration gradient in tissue constructs, resulting from a combination of high-affinity binding interactions and a high cellular internalization rate. These gradients are sustained throughout the entire culture duration, leading to highly heterogeneous tissue growth; biochemical and histological measurements support that while biochemical content is enhanced up to 4-fold at the construct periphery, enhancements are entirely absent beyond 1 mm from the construct surface. Second, construct-encapsulated chondrocytes continuously secrete large amounts of endogenous TGF-β in its latent form, a portion of which undergoes cell-mediated activation and enhances biosynthesis uniformly throughout the tissue. Finally, motivated by these prior insights, we demonstrate that the alternative supplementation of additional exogenous latent TGF-β enhances biosynthesis uniformly throughout tissue constructs, leading to enhanced but homogeneous tissue growth. This novel demonstration suggests that latent TGF-β supplementation may be utilized as an important tool for the translational engineering of large cartilage constructs that will be required to repair the large osteoarthritic defects observed clinically. PMID:26599624

  16. Synchrotron radiation facilities

    CERN Multimedia

    1972-01-01

    Particularly in the past few years, interest in using the synchrotron radiation emanating from high energy, circular electron machines has grown considerably. In our February issue we included an article on the synchrotron radiation facility at Frascati. This month we are spreading the net wider — saying something about the properties of the radiation, listing the centres where synchrotron radiation facilities exist, adding a brief description of three of them and mentioning areas of physics in which the facilities are used.

  17. Synchrotron radiation: science & applications

    OpenAIRE

    Aranda, Miguel A. G.

    2015-01-01

    This general talk is devoted to briefly introduce the main uses and applications of synchrotron radiation. An initial introduction will be dedicated to describe a synchrotron as a Large Facility devoted to produce photons that will be used to carry out excellent science. The five outstanding main characteristics of synchrotron radiation are: i) High brilliance and collimation ii) Wavelength tunability iii) Beamsize tunability iv) Defined polarization v) Time structure vi)...

  18. A medical proton synchrotron

    International Nuclear Information System (INIS)

    A special medical weak-focusing synchrotron using only wedge focusing at dipole ends, is proposed to make a proton cancer therapy. A new method of the turn number calculation in a proton synchrotron allowing to calculate the energy gain per turn, is formulated. 13 refs.; 10 figs.; 1 tab

  19. Synchrotron radiation from protons

    Energy Technology Data Exchange (ETDEWEB)

    Dutt, S.K.

    1992-12-01

    Synchrotron radiation from protons, though described by the same equations as the radiation from electrons, exhibits a number of interesting features on account of the parameters reached in praxis. In this presentation, we shall point out some of the features relating to (i) normal synchrotron radiation from dipoles in proton machines such as the High Energy Booster and the Superconducting Super Collider; (ii) synchrotron radiation from short dipoles, and its application to light monitors for proton machines, and (iii) synchrotron radiation from undulators in the limit when, the deflection parameter is much smaller than unity. The material for this presentation is taken largely from the work of Hofmann, Coisson, Bossart, and their collaborators, and from a paper by Kim. We shall emphasize the qualitative aspects of synchrotron radiation in the cases mentioned above, making, when possible, simple arguments for estimating the spectral and angular properties of the radiation. Detailed analyses can be found in the literature.

  20. National Synchrotron Light Source

    International Nuclear Information System (INIS)

    This report discussion research being conducted at the National Synchrotron light source. In particular, this report contains operations summaries; symposia, workshops, and projects; NSLS highlights; and abstracts of science at the NSLS

  1. The Australian synchrotron project

    International Nuclear Information System (INIS)

    Full text: The Australian Synchrotron to be built at Monash University, is a synchrotron light facility based on a 3-GeV electron storage ring. It is scheduled to be fully operational in 2007. In this paper we describe the accelerator systems that lie at the heart of the facility, and describe the spectral characteristics of the 'light' - ranging from infra-red to hard x-rays - that will be provided from bend magnets, undulators, and wigglers

  2. RF gymnastics in synchrotrons

    OpenAIRE

    Garoby, R.

    2011-01-01

    The RF systems installed in synchrotrons can be used to change the longitudinal beam characteristics. 'RF gymnastics' designates manipulations of the RF parameters aimed at providing such non-trivial changes. Some keep the number of bunches constant while changing bunch length, energy spread, emittance, or distance between bunches. Others are used to change the number of bunches. After recalling the basics of longitudinal beam dynamics in a hadron synchrotron, this paper deals with the most c...

  3. Future Synchrotron Radiation Sources

    CERN Document Server

    Winick, Herman

    2003-01-01

    Sources of synchrotron radiation (also called synchrotron light) and their associated research facilities have experienced a spectacular growth in number, performance, and breadth of application in the past two to three decades. In 1978 there were eleven electron storage rings used as light sources. Three of these were small rings, all below 500 mega-electron volts (MeV), dedicated to this purpose; the others, with energy up to 5 giga-electron volts (GeV), were used parasitically during the operation of the ring for high energy physics research. In addition, at that time synchrotron radiation from nine cyclic electron synchrotrons, with energy up to 5 GeV, was also used parasitically. At present no cyclic synchrotrons are used, while about 50 electron storage rings are in operation around the world as fully dedicated light sources for basic and applied research in a wide variety of fields. Among these fields are structural molecular biology, molecular environmental science, materials, analytic chemistry, micr...

  4. RF gymnastics in synchrotrons

    CERN Document Server

    Garoby, R

    2011-01-01

    The RF systems installed in synchrotrons can be used to change the longitudinal beam characteristics. 'RF gymnastics' designates manipulations of the RF parameters aimed at providing such non-trivial changes. Some keep the number of bunches constant while changing bunch length, energy spread, emittance, or distance between bunches. Others are used to change the number of bunches. After recalling the basics of longitudinal beam dynamics in a hadron synchrotron, this paper deals with the most commonly used gymnastics. Their principle is described as well as their performance and limitations.

  5. RF Gymnastics in Synchrotrons

    CERN Document Server

    Garoby, R

    2005-01-01

    The RF systems installed in synchrotrons can be used to change the longitudinal beam characteristics. "RF gymnastics" designates manipulations of the RF parameters aimed at providing such non-trivial changes. Some keep the number of bunches constant while changing bunch length, energy spread, emittance or distance between bunches. Others are used to change the number of bunches. After recalling the basics of longitudinal beam dynamics in a hadron synchrotron, this paper deals with the most commonly used gymnastics. Their principle is described as well as their performance and limitations.

  6. The Proton Synchrotron, going strong at fifty years

    CERN Multimedia

    Django Manglunki

    It was on the evening of 24 November 1959 that an incredulous Hildred Blewett, on detachment to CERN from the Brookhaven laboratory, exclaimed “Yes! We’re through transition!” The first beam of ten billion protons had not only broken through the 5.2 GeV barrier but gone on all the way to 24 GeV, the machine’s top energy at that time.   An operational screenshot from the PS, taken on its 50th anniversary. The three white peaks depict different phases (cycles) of the PS’s operation. In the first and third cycle, the PS is producing a very low-intensity beam for LHC commissioning. In the second cycle, protons are being spilled out for use in the East Area. Fifty years ago the PS, the first strong-focusing proton synchrotron using alternating gradient technology, first began to circulate beams at an unprecedented level of energy. Over the years, a complex of linear and circular accelerators and storage rings grew up around the PS. In the mid-1990s ...

  7. CORNELL: Synchrotron 25

    International Nuclear Information System (INIS)

    A recent celebration marked the twenty-fifth anniversary of the Cornell Electron Synchrotron. The major milestone in the commissioning of the synchrotron was on October 11, 1967 when Helen Edwards, Boyce McDaniel, and Maury Tigner achieved a 7 GeV beam, a worldrecord energy for electron synchrotrons at that time. Like so many advances in experimental physics, this occurred early in the morning - 3 a.m.! The transition from accelerator commissioning to high energy physics operation was extremely rapid; 7 GeV operation for data collection was routine just five weeks later. Throughout its life as a source of photon and electron beams for fixed target experiments, the synchrotron maintained energy leadership for circular electron machines. Originally designed for operation at 10 GeV, eventually it consistently provided beams for experiments at energies up to 11.6 GeV. It now operates at 5 GeV, serving as the injector for the CESR electron-positron storage ring. Robert Wilson was director of the laboratory during the design and most of the construction of the machine. He left near the end of the construction to become the first director of Fermilab and was replaced by Boyce McDaniel, who guided the laboratory from the completion of the synchrotron to the construction and early operation of CESR. Wilson recalled how the laboratory had originally proposed a 3 GeV turnkey machine to be built entirely by industry and would fit in the space previously occupied by earlier Cornell accelerators. However, members of the laboratory realized that 3 GeV would not open new physics frontiers, that the construction of the accelerator was much of the fun of doing high energy physics experiments, and that a more challenging project was needed. This led to the proposal for the 10 GeV synchrotron which was built in the ''Cornell Style'' with many of the components fabricated and nearly all of the assembly done at Cornell

  8. Improvements in the Rapid Cycling Synchrotron

    International Nuclear Information System (INIS)

    The Rapid Cycling Synchrotron1 (RCS), originally designed as an injection energy booster for the Zero Gradient Synchrotron (ZGS), operated under contraints imposed by ZGS operation until December 1979. Once these restraints were removed, the RCS made rapid strides toward its nearterm goals of 8 μA of protons for Argonne National Laboratory's (ANL) Intense Pulsed Neutron Source (IPNS) program. Reliable 30 Hz operation was achieved in the spring of 1980 with beams as high as 2 x 1012 protons per pulse and weekly average intensities of over 6 μA on target. These gains resulted from better injection matching, more efficient RF turn-on and dynamic chromatricity control. A high intensity small diameter synchrotron, such as the RCS, has special problems with loss control which dictate prudence during intensity improvment activities. Additional improvements were made to the machine starting in August of 1980 while the extraction magnets were relocated for operation with the IPNS-I target. These improvements have now been completed. Startup of the accelerator is now underway, and it is clear that these modifications have resulted in a radio-actively cleaner operation. It is too early to evaluate the effects of the improvements on intensity and reliability, but a single pulse extracted intensity of 2.4 x 1012 protons has been achieved, a 20% increase. The studies and equipment leading to the intensity gains are discussed. (orig.)

  9. Prospects for studying vacuum polarisation using dipole and synchrotron radiation

    CERN Document Server

    Ilderton, Anton

    2016-01-01

    The measurement of vacuum polarisation effects, in particular vacuum birefringence, using combined optical and x-ray laser pulses is now actively pursued. Here we briefly examine the feasibility of two alternative setups. The first utilises an alternative target, namely a converging dipole pulse, and the second uses an alternative probe, namely the synchrotron-like emission from highly energetic particles, themselves interacting with a laser pulse. The latter setup has been proposed for experiments at ELI-NP.

  10. Prospects for studying vacuum polarisation using dipole and synchrotron radiation

    OpenAIRE

    Ilderton, Anton; Marklund, Mattias

    2016-01-01

    The measurement of vacuum polarisation effects, in particular vacuum birefringence, using combined optical and x-ray laser pulses is now actively pursued. Here we briefly examine the feasibility of two alternative setups. The first utilises an alternative target, namely a converging dipole pulse, and the second uses an alternative probe, namely the synchrotron-like emission from highly energetic particles, themselves interacting with a laser pulse. The latter setup has been proposed for exper...

  11. Brazilian Synchrotron Radiation Project

    International Nuclear Information System (INIS)

    The proposal for a Brazilian national laboratory for synchrotron radiation is presented. The first design study led to a system consisting of a LINAC, an injection ring and a low emittance storage ring. The main ring is designed to be upgraded to 3GeV with an emittance of 4 x 10-8 rad.m. The design study also indicated the possibility of using the injection ring as a soft x-Rays/VUV source

  12. On the implementation of computed laminography using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Helfen, L.; Pernot, P.; Elyyan, M. [Institut fuer Synchrotronstrahlung (ISS/ANKA), Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe (Germany); Myagotin, A. [Institut fuer Synchrotronstrahlung (ISS/ANKA), Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe (Germany); Saint-Petersburg State University of Civil Aviation, 196210, Saint-Petersburg (Russian Federation); Mikulik, P. [Department of Condensed Matter Physics, Faculty of Science, Masaryk University, CZ-61137 Brno (Czech Republic); Voropaev, A. [Saint-Petersburg State University of Civil Aviation, 196210, Saint-Petersburg (Russian Federation); Di Michiel, M.; Baruchel, J. [European Synchrotron Radiation Facility (ESRF), F-38043 Grenoble (France); Baumbach, T. [Institut fuer Synchrotronstrahlung (ISS/ANKA), Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe (Germany); LAS, Karlsruhe Institute of Technology, D-76128 Karlsruhe (Germany)

    2011-06-15

    Hard x rays from a synchrotron source are used in this implementation of computed laminography for three-dimensional (3D) imaging of flat, laterally extended objects. Due to outstanding properties of synchrotron light, high spatial resolution down to the micrometer scale can be attained, even for specimens having lateral dimensions of several decimeters. Operating either with a monochromatic or with a white synchrotron beam, the method can be optimized to attain high sensitivity or considerable inspection throughput in synchrotron user and small-batch industrial experiments. The article describes the details of experimental setups, alignment procedures, and the underlying reconstruction principles. Imaging of interconnections in flip-chip and wire-bonded devices illustrates the peculiarities of the method compared to its alternatives and demonstrates the wide application potential for the 3D inspection and quality assessment in microsystem technology.

  13. On the implementation of computed laminography using synchrotron radiation

    International Nuclear Information System (INIS)

    Hard x rays from a synchrotron source are used in this implementation of computed laminography for three-dimensional (3D) imaging of flat, laterally extended objects. Due to outstanding properties of synchrotron light, high spatial resolution down to the micrometer scale can be attained, even for specimens having lateral dimensions of several decimeters. Operating either with a monochromatic or with a white synchrotron beam, the method can be optimized to attain high sensitivity or considerable inspection throughput in synchrotron user and small-batch industrial experiments. The article describes the details of experimental setups, alignment procedures, and the underlying reconstruction principles. Imaging of interconnections in flip-chip and wire-bonded devices illustrates the peculiarities of the method compared to its alternatives and demonstrates the wide application potential for the 3D inspection and quality assessment in microsystem technology.

  14. On the implementation of computed laminography using synchrotron radiation

    Science.gov (United States)

    Helfen, L.; Myagotin, A.; Mikulík, P.; Pernot, P.; Voropaev, A.; Elyyan, M.; Di Michiel, M.; Baruchel, J.; Baumbach, T.

    2011-06-01

    Hard x rays from a synchrotron source are used in this implementation of computed laminography for three-dimensional (3D) imaging of flat, laterally extended objects. Due to outstanding properties of synchrotron light, high spatial resolution down to the micrometer scale can be attained, even for specimens having lateral dimensions of several decimeters. Operating either with a monochromatic or with a white synchrotron beam, the method can be optimized to attain high sensitivity or considerable inspection throughput in synchrotron user and small-batch industrial experiments. The article describes the details of experimental setups, alignment procedures, and the underlying reconstruction principles. Imaging of interconnections in flip-chip and wire-bonded devices illustrates the peculiarities of the method compared to its alternatives and demonstrates the wide application potential for the 3D inspection and quality assessment in microsystem technology.

  15. Engineering application of synchrotron radiation

    International Nuclear Information System (INIS)

    The synchrotron radiation which is generated when the circular motion of fast electrons is carried out in vacuum has been studied as the source of X-ray and ultraviolet ray for physical property research, but recently attention has been paid to its industrial application. In this report, from the viewpoint of how to utilize the properties of synchrotron radiation to electronic industries, the recent trend of research is explained. Synchrotron radiation is the electromagnetic waves radiated in the tangential direction to their track when the electrons at the velocity close to light velocity carry out acceleration motion. The synchrotron radiation generator is an electron storage ring. Synchrotron radiation is the beam having good parallelism, concentrating in the orbit plane of electrons, and is led to respective experimental devices with beam lines. Synchrotron radiation lithography has become the start of its industrial application. The process technology being excited by synchrotron radiation, the evaluation of materials using synchrotron radiation, small synchrotron radiation generators and the new sources of light are reported. Synchrotron radiation is the important technological field developed by the joint work of physics and engineering in the latter half of 20th century, following semiconductors, lasers and superconductivity. (K.I.)

  16. Synchrotron Radiation as CMB Foreground

    OpenAIRE

    Smoot, George F.

    1999-01-01

    Synchrotron emission is an important process in Galactic dynamics and a potentially confusing foreground for cosmic microwave background (CMB) radiation observations. Though the mechanism of synchrotron emission is well understood, the details for the Galaxy and many external sources are not well characterized. Quality maps at multiple frequencies are lacking but needed for a full understanding of the Galactic synchrotron emission, including intensity, spectrum, and spectral variation. At hig...

  17. On gradient field theories: gradient magnetostatics and gradient elasticity

    OpenAIRE

    Lazar, Markus

    2014-01-01

    In this work the fundamentals of gradient field theories are presented and reviewed. In particular, the theories of gradient magnetostatics and gradient elasticity are investigated and compared. For gradient magnetostatics, non-singular expressions for the magnetic vector gauge potential, the Biot-Savart law, the Lorentz force and the mutual interaction energy of two electric current loops are derived and discussed. For gradient elasticity, non-singular forms of all dislocation key-formulas (...

  18. Synchrotron Radiation as CMB Foreground

    CERN Document Server

    Smoot, G F

    1999-01-01

    Synchrotron emission is an important process in Galactic dynamics and a potentially confusing foreground for cosmic microwave background (CMB) radiation observations. Though the mechanism of synchrotron emission is well understood, the details for the Galaxy and many external sources are not well characterized. Quality maps at multiple frequencies are lacking but needed for a full understanding of the Galactic synchrotron emission, including intensity, spectrum, and spectral variation. At high frequencies (> 70 GHz) synchrotron emission is not a severe limitation to precise CMB observations well away from the Galactic plane.

  19. Synchrotron refraction CT and synchrotron bragg magnification CT for NDE

    International Nuclear Information System (INIS)

    X-Ray Refraction Topography techniques are based on Ultra Small Angle Scattering by micro structural elements causing phase related effects like refraction and total reflection at a few minutes of arc as the refractive index of X-rays is nearly unity. The refraction contrast is several times higher than 'true absorption' and results in images of cracks, pores and fibre de-bonding separations below the spatial resolution of the detector. In most cases the investigated inner surface and interface structures correlate to mechanical properties. For the exploration of micro structured materials the refraction technique has been improved by a 3D Synchrotron Refraction Computed Tomography test station. The specimen is placed in an X-ray beam between two single crystals, which suppresses all sample scattering. In addition an asymmetric cut second crystal can magnify the image up to 50 times revealing nano meter resolution. The technique is an alternative to other attempts on raising the spatial resolution of CT machines. (authors)

  20. Compact synchrotron radiation source

    International Nuclear Information System (INIS)

    A compact 800 MeV synchrotron radiation source is discussed. The storage ring has a circumference of 30.3 m, two 90 degree and four 45 degree bending magnet sections, two long straight sections and four short straight sections. The radius of the bending magnet is 2.224m. The critical wave length is 24A. The injector is a 15 Mev Microtron Electrons are accelerated from 15 Mev to 800 Mev by ramping the field of the ring. The expected stored current will be around 100 ma

  1. The synchrotron radiation

    International Nuclear Information System (INIS)

    Synchrotron Radiation is a fantastic source of electromagnetic radiation the energy spectrum of which spreads continuously from the far infrared to hard X-rays. For this reason a wide part of the scientific community, fundamentalists as well as industry, is concerned by its use. We shall describe here the main properties of this light source and give two examples of application in the field of characterization of materials: EXAFS (Extended X-Ray Absorption Fine Structure) and X-ray fluorescence. (author). 8 figs., 21 refs

  2. Synchrotron light beam and a synchrotron light experiment facility

    International Nuclear Information System (INIS)

    In the National Laboratory for High Energy Physics, about two years ago, the requirements of synchrotron light beam in respective measuring instruments were discussed. Then, also the arrangement (lattice) of a storage ring, the nature of synchrotron light beam, a synchrotron light experiment facility and the arrangement of the beam lines were studied. During the period of two years since then, due to the changes in the circumstances, the design of the lattice was altered. Accordingly, the arrangement of the beam lines and of measuring instruments were largely changed. At this point, the results of discussions in various meetings are described, though they may still be subject to future changes, with due consideration to beam, environment and beam lines required for the design of the measuring instruments: (1) storage ring and synchrotron light beam, (2) requirements on small beam size and beam stability, (3) a synchrotron light experiment facility. (J.P.N.)

  3. A novel approach to synchrotron radiation simulation

    CERN Document Server

    Trad, G; Goldblatt, A; Mazzoni, S; Roncarolo, F

    2014-01-01

    At the Large Hadron Collider (LHC) at CERN, synchrotron radiation (SR) is used to continuously monitor the transverse properties of the beams. Unfortunately the machine and beam parameters are such that the useful radiation emitted inside a separation dipole, chosen as source, is diffraction limited heavily affecting the accuracy of the measurement. In order to deconvolve the diffraction effects from the acquired beam images and in order to design an alternative monitor based on a double slit interferometer an extensive study of the synchrotron light source and of the optical propagation has been made. This study is based on simulations combining together several existing tools: SRW for the source, ZEMAX for the transport and MATLAB for the “glue” and analysis of the results. The resulting tool is very powerful and can be easily adapted to other synchrotron radiation problems. In this paper the simulation package and the way it is used will be described as well as the results obtained for the LHC and SPS.

  4. Synchrotron radiation source Indus-1

    International Nuclear Information System (INIS)

    Indus-1 is a 450 MeV electron storage ring for the production of the synchrotron radiation in VUV range with a critical wavelength of 61 A. In this paper we discuss the synchrotron radiation source Indus-1 and report some results of its present performance. Besides, results of beam lifetime studies are also reported. (author)

  5. SAXS experiments using synchrotron sources

    International Nuclear Information System (INIS)

    The main characteristics of SAXS (small angle x-ray scattering) experimental instruments associated with classical and synchrotron sources are outlined. Some examples of applications of synchrotron radiation to SAXS studies of solid state phase separation, molecular aggregation, gel formation, porous materials and sintering processes, are described. An overview of recent instrumental progress and tendencies is presented

  6. Induction synchrotron and its applications

    International Nuclear Information System (INIS)

    An RF synchrotron has been the indispensable device for nuclear physics and high energy physics experiments so far. Instead of this conventional accelerator, an induction synchrotron has been proposed and its demonstration is going to be done in the near future. The induction synchrotron is capable of accelerating a super-bunch of 1 μs long. A new generation of proton driver or hadron collider accommodating super-bunches, which claims to increase their luminosity ten times larger, is under consideration. Key devices to realize the novel induction synchrotron are a pulse modulator and induction accelerating cavity being operated at 1 MHz rep-rate. The concept and characteristics of the induction synchrotron are presented including the outline of R and D works. (author)

  7. Primakoff effect: synchrotron and coulomb mechanisms of axion emission

    International Nuclear Information System (INIS)

    For the first time the axion radiative emission by alternating electromagnetic field Fa → γa is considered due to Primakoff effect. As a concrete supplement, the synchrotron and Coulomb mechanisms are discussed and in the last case the alternating field is formed at the infinite motion of a charge in a Coulomb center field. The estimates for contributions of these effects into axion luminosity of magnetic neutron stars and the Sun are determined

  8. Primakoff effect: Synchrotron and Coulomb mechanisms of axion emission

    International Nuclear Information System (INIS)

    The Primakoff effect-induced radiative emission of axions by an alternating electromagnetic field, Fa → γa, is considered for the first time. The synchrotron mechanism and the Coulomb mechanism--in the latter case, the alternating field is formed when a charge executes an infinite motion in the field of a Coulomb center--are considered as specific examples. The contributions of these effects to the axion emissivity of magnetic neutron stars and of the Sun are estimated

  9. Proton synchrotron accelerator theory

    International Nuclear Information System (INIS)

    This is the text of a series of lectures given as part of the CERN Academic Training Programme and primarily intended for young engineers and technicians in preparation for the running-in of the 400 GeV Super Proton Synchrotron (SPS). Following the definition of basic quantities, the problems of betatron motion and the effect of momentum spread and orbital errors on the transverse motion of the beam are reviewed. Consideration is then given to multipole fields, chromaticity and non-linear resonances. After dealing with basic relations governing longitudinal beam dynamics, the space-charge, resistive-wall and other collective effects are treated, with reference to precautions in the SPS to prevent their occurrence. (Auth.)

  10. Improvements in the rapid cycling synchrotron

    International Nuclear Information System (INIS)

    The Rapid Cycling Snychrotron1 (RCS), originally designed as an injection energy booster for the Zero Gradient Synchrotron (ZGS), operated under constraints imposed by ZGS operation until December 1979. Once these restraints were removed, the RCS made rapid strides toward its nearterm goals of 8 μA of protons for Argonne National Laboratory's (ANL) Intense Pulsed Neutron Source (IPNS) program. Reliable 30 Hz operation was achieved in the spring of 1980 with beams as high as 2 x 1012 protons per pulse and weekly average intensities of over 6 μA on target. These gains resulted from better injection matching, more efficient RF turn-on and dynamic chromaticity control. A high intensity small diameter synchrotron, such as the RCS, has special problems with loss control which dictate prudence during intensity improvement activities. Additional improvements were made to the machine starting in August of 1980 while the extraction magnets were relocated for operation with the IPNS-I target. These improvements have now been completed. Startup of the accelerator is now underway, and it is clear that these modifications have resulted in a radioactively cleaner operation. It is too early to evaluate the effects of the improvements on intensity and reliability, but a single pulse extracted intensity of 2.4 x 1012 protons has been achieved, a 20% increase. The studies and equipment leading to the intensity gains are discussed. (orig.)

  11. Project X with Rapid Cycling and Dual Storage Superconducting Synchrotrons

    CERN Document Server

    Piekarz, Henryk

    2012-01-01

    Investigation of neutrino oscillations and rare meson decays are main physics goals of Project X. The successful physics outcome relies on the feasibility of high-intensity neutrino and meson (K+ and \\mu) beams. In order to meet this goal we propose accelerator system dominated by the synchrotrons (Option A) as a technologically easier and significantly more cost-effective alternative to the accelerator system dominated by the linear accelerators (Option B). The synchrotron-based accelerator system and its main components are outlined and the expected proton beam power for the neutrino and meson beams production is presented and discussed.

  12. The European Synchrotron Radiation Facility

    DEFF Research Database (Denmark)

    Buras, B.; Materlik, G.

    In recent years, X-ray synchrotron radiation became a powerful tool for studies of condensed matter, and in view of that a proposal for the construction of a European Synchrotron Radiation Facility (ESRF) was elaborated in some detail by the European Synchrotron Radiation Project. The heart of the...... great flexibility and a small emittance (7×10−9 rad m) leading to a very high brilliance (1019 photons/(s mm2 mrad2) in a relative bandwidth of 0.1% in case of a 1 Å undulator). The overview, as seen from the users point of view, gives a brief account of the storage ring, emitted radiation...

  13. Biomedical applications of synchrotron radiation

    International Nuclear Information System (INIS)

    Synchrotron radiation techniques application in medical diagnostics have been presented especially for: trace element analysis in tissues, elemental mapping, chemical speciation at trace levels, chemical structure determination. Presented techniques are very useful for early cancer discovery

  14. Mossbauer spectroscopy with synchrotron radiation

    International Nuclear Information System (INIS)

    The principles underlying observation of the Mossbauer effect with synchrotron radiation are explained. The current status of the field is reviewed, and prospects for dedicated experimental stations on third generation machines are discussed

  15. Synchrotron scientists unpack their suitcases

    International Nuclear Information System (INIS)

    Australian Synchrotron will enable 3000 Australian scientists to overcome the tyranny of distance and accelerate their research into fields as diverse as drug development, IVF and self-cleaning textiles

  16. Superpower monochromatic coherent synchrotron radiation

    International Nuclear Information System (INIS)

    Here a special case of coherent synchrotron radiation from relativistic electron bunches distributed uniformly on a circular orbit is investigated. The possibility to obtain a monochromatic intense coherent radiation in the long-wavelength region is shown

  17. Spin Echo in Synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Alexander W.; /SLAC; Courant, Ernest D.; /Brookhaven

    2006-12-01

    As a polarized beam is accelerated through a depolarization resonance, its polarization is reduced by a well-defined calculable reduction factor. When the beam subsequently crosses a second resonance, the final beam polarization is considered to be reduced by the product of the two reduction factors corresponding to the two crossings, each calculated independently of the other. This is a good approximation when the spread of spin precession frequency {Delta}{nu}{sub spin} of the beam (particularly due to its energy spread) is sufficiently large that the spin precession phases of individual particles smear out completely during the time {tau} between the two crossings. This approximate picture, however, ignores two spin dynamics effects: an interference effect and a spin echo effect. This paper is to address these two effects. The interference effect occurs when {Delta}{nu}{sub spin} is too small, or when {tau} is too short, to complete the smearing process. In this case, the two resonance crossings interfere with each other, and the final polarization exhibits constructive or destructive patterns depending on the exact value of {tau}. Typically, the beam's energy spread is large and this interference effect does not occur. To study this effect, therefore, it is necessary to reduce the beam energy spread and to consider two resonance crossings very close to each other. The other mechanism, also due to the interplay between two resonance crossings, is spin echo. It turns out that even when the precession phases appear to be completely smeared between the two crossings, there will still be a sudden and short-lived echo signal of beam polarization at a time {tau} after the second crossing; the magnitude of which can be as large as 57%. This echo signal exists even when the beam has a sizable energy spread and when {tau} is very large, and could be a sensitive (albeit challenging) way to experimentally test the intricate spin dynamics in a synchrotron. After giving

  18. Prospects for compact high-intensity laser synchrotron x-ray and gamma sources

    International Nuclear Information System (INIS)

    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 as prototype LSS brick stones. 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 angstrom) x-rays of 10-ps pulse duration, with a flux of ∼ 1019 photons/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

  19. Contact microscopy with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Panessa-Warren, B.J.

    1985-10-01

    Soft x-ray contact microscopy with synchrotron radiation offers the biologist and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM or SEM methods (i.e. hydrated samples, samples easily damaged by an electron beam, electron dense samples, thick specimens, unstained low contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash x-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of x-ray wavelengths or specific individual wavelengths which optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of x-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples. 24 refs., 10 figs.

  20. Contact microscopy with synchrotron radiation

    International Nuclear Information System (INIS)

    Soft x-ray contact microscopy with synchrotron radiation offers the biologist and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM or SEM methods (i.e. hydrated samples, samples easily damaged by an electron beam, electron dense samples, thick specimens, unstained low contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash x-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of x-ray wavelengths or specific individual wavelengths which optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of x-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples. 24 refs., 10 figs

  1. The Australian Synchrotron Project - Update

    CERN Document Server

    Jackson, Alan

    2004-01-01

    The Australian Synchrotron - a synchrotron light facility based on a 3-GeV electron storage ring is under construction at a site in the Metropolitan District of Melbourne. Building preparation started on a "green-field" site in September 2003 and staff moved in to their new offices in February 2005. Installation of the technical equipment started in April 2005 with all accelerator contracts expected to be completed before April 2006. Storage Ring commissioning with beam will start in June 2006, and project completion is scheduled for March 2007. In this paper we present an overview of the facility and discuss progress to date in meeting this very aggressive schedule.

  2. Synchrotron radiation and structural proteomics

    CERN Document Server

    Pechkova, Eugenia

    2011-01-01

    This book presents an overview of the current state of research in both synchrotron radiation and structural proteomics from different laboratories worldwide. The book presents recent research results in the most advanced methods of synchrotron radiation analysis, protein micro- and nano crystallography, X-ray scattering and X-ray optics, coherent X-Ray diffraction, and laser cutting and contactless sample manipulation are described in details. The book focuses on biological applications and highlights important aspects such as radiation damage and molecular modeling.

  3. DESY: Synchrotron and storage rings

    CERN Multimedia

    1972-01-01

    An improvement programme has been under way for several years at the 7.5 GeV électron synchrotron at DESY. In particular it has been designed to increase the accelerated beam intensity, to achieve better quality of the ejected électron beams and photon beams and to improve machine reliability.

  4. Biological physics and synchrotron radiation

    International Nuclear Information System (INIS)

    This conference deals with the applications of synchrotron radiation to current problems in biology and medicine. Seven sessions take stock on the subject: sources and detectors; inelastic scattering and dynamics; muscle diffraction; reaction mechanisms; macromolecular assemblies; medical applications; imaging and spectroscopy. The document presents the papers abstracts. (A.L.B.)

  5. Biological physics and synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Filhol, J.M.; Chavanne, J. [European Synchrotron Radiation Facility, 38 - Grenoble (France); Weckert, E. [Hasylab at Desy, Hamburg (Germany)] [and others

    2001-07-01

    This conference deals with the applications of synchrotron radiation to current problems in biology and medicine. Seven sessions take stock on the subject: sources and detectors; inelastic scattering and dynamics; muscle diffraction; reaction mechanisms; macromolecular assemblies; medical applications; imaging and spectroscopy. The document presents the papers abstracts. (A.L.B.)

  6. Synchrotron radiation in material science

    International Nuclear Information System (INIS)

    A brief review on the several experimental techniques (XRD, SAXS, EXAFS, IRRS, etc...) which, utilizing of synchrotron radiation can be applied in glass structural studies, is presented. The major part of these techniques can be also used for studies of other materials such as polymers, metals, etc... (L.C.)

  7. Synchrotron radiation and biomedical imaging

    International Nuclear Information System (INIS)

    In this lecture we describe the characteristics of Synchrotron radiation as a source of X rays. We discuss the properties of SR arc sources, wigglers, undulators and the use of backscattering of laser light. Applications to angiography, X ray microscopy and tomography are reviewed. 16 refs., 23 figs

  8. Medical applications of synchrotron radiation

    International Nuclear Information System (INIS)

    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

  9. Multipole correction in large synchrotrons

    International Nuclear Information System (INIS)

    A new method of correcting dynamic nonlinearities due to the multipole content of a synchrotron such as the Superconducting Super Collider is discussed. The method uses lumped multipole elements placed at the center (C) of the accelerator half-cells as well as elements near the focusing (F) and defocusing (D) quads. In a first approximation, the corrector strengths follow Simpson's Rule. Correction of second-order sextupole nonlinearities may also be obtained with the F, C, and D octupoles. Correction of nonlinearities by about three orders of magnitude are obtained, and simple solutions to a fundamental problem in synchrotrons are demonstrated. Applications to the CERN Large Hadron Collider and lower energy machines, as well as extensions for quadrupole correction, are also discussed

  10. Medical Applications of Synchrotron Radiation

    Science.gov (United States)

    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.

  11. Threedimensional microfabrication using synchrotron radiation

    International Nuclear Information System (INIS)

    For fabricating microstructures with extreme structural heights a technology has been developed which is based on deep-etch lithography and subsequent replication processes. A particularly high precision is achieved if the lithographic process is carried out by means of synchrotron radiation. Electroforming and molding processes are used for the replication of microstructures from a large variety of materials. The field of application comprises sensors, electrical and optical microconnectors, components for fluid technology, microfiltration systems and novel composite materials. (author)

  12. Proposals for synchrotron light sources

    International Nuclear Information System (INIS)

    Ever since it was first applied in the 1960's synchrotron radiation from an accelerating electron beam has been gaining popularity as a powerful tool for research and development in a wide variety of fields of science and technology. By now there are some 20 facilities operating either parasitically or dedicatedly for synchrotron radiation research in different parts of the world. In addition there are another 20 facilities either in construction or in various stages of proposal and design. The experiences gained from the operating facilities and the recent development of insertion devices such as wigglers and undulators as radiation sources led to a new set of requirements on the design of synchrotron radiation storage rings for optimum utility. The surprisingly uniform applicability and unanimous acceptance of these criteria give assurance that they are indeed valid criteria derived form mature considerations and experiences. Instead of describing the design of each of these new facilities it is, thus, more effective to discuss these desirable design features and indicate how they are incorporated in the design using machines listed as examples. 9 refs., 7 figs., 2 tabs

  13. Beam diagnostics with synchrotron radiation

    International Nuclear Information System (INIS)

    Synchrotron radiation is often used to measure the dimensions of an electron beam. The transverse size is obtained from an image of the beam cross section formed by means of the emitted synchrotron radiation. Because of the small natural opening angle the resolution is limited by diffraction. The angular spread of the particles in the beam can be measured by observing the radiation directly. Here, the resolution is limited by the natural opening angle of the emitted light. Measuring both beam cross section and angular spread gives the emittance of the beam. However, in most cases only one of these two parameters is observed and the other deduced from the known particle beam optics at the source of the radiation. Usually one observes radiation emitted in long bending magnets. However, short magnets and undulators are also useful sources for these measurements. For practical reasons the beam diagnostics is carried out using visible or ultraviolet light. This part of the spectrum is usually far below the critical frequency, and corresponding approximations can be applied. Synchrotron radiation is an extremely useful tool for diagnostics in electron (or positron) rings. In some cases it has also served in proton rings using special magnets. (author)

  14. Rf capture studies for injection into a synchrotron

    International Nuclear Information System (INIS)

    The capture process for a rapid cycling protron synchrotron is studied by numerical simulation. The rf-programming is optimized to allow efficient capture such that minimum particle losses and reasonable capture voltage are attained. The total capture time is constrained to be less than 700 μseconds. Two methods of trapping the injected beam by the synchrotron rf system are examined: by stationary adiabatic capture and by synchronous injection in a standing bucket of the ring. In the adiabatic method, the non-linear function of Lilliequist and Symon is employed. The simulation allows the ''tracking back'' of the original distribution of any set of particles, in particular of those not captured at a given time, which is useful in studying injection alternatives such as shaping the phase-space density prior to injection. The simulation results will be used to design a chopper system to facilitate loss-free injection

  15. Synchrotron Environmental Science-I Workshop Report

    International Nuclear Information System (INIS)

    Attendees of the Synchrotrons Environmental Science 1 (SES-1) workshop represented a broad spectrum of environmental science research areas and expertise in all of the current synchrotrons techniques (X-ray scattering and diffraction, X-ray absorption spectroscopy, and two- and three-dimensional X-ray imaging). These individuals came together to discuss current measurement obstacles in environmental research and, more specifically, ways to overcome such obstacles by applying synchrotrons radiation techniques. Significant obstacles in measurement affect virtually all of the research issues described. Attendees identified synchrotrons approaches of potential value in their research. A number of the environmental research studies discussed are currently being addressed with some success by synchrotron-based approaches. Nevertheless, improvements in low-Z measurement capabilities are needed to facilitate the use of synchrotrons radiation methodologies in environmental research

  16. Linac for the National Synchrotron Light Source

    International Nuclear Information System (INIS)

    The nominally 100 MeV electron linear accelerator to be used as an injector for the booster synchrotron of the National Synchrotron Light Source is described. The machine utilizes a combination of Varian and SLAC accelerating guides and is interfaced by means of a microprocessor-based Intel Multibus system, to the Data General central control computer. Provision for emittance and momentum measurement is provided in the transport line between the linac and the booster synchrotron

  17. RF acceleration system for 3 GeV proton synchrotron in JAERI-KEK joint project

    International Nuclear Information System (INIS)

    RF acceleration system for 3 GeV proton synchrotron in Joint JAERI-KEK high intensity proton accelerator project is described. In this synchrotron, since 8.3 x 1013 protons must be accelerated from 400 MeV to 3 GeV within 20 ms, wide-band frequency range and high accelerating voltage are required, and the system must be stable under heavy beam loading. From the results of R and D works over the past several years, high gradient rf cavity loaded with Magnetic Alloy and 1.2 MW class push-pull tetrode tube amplifier will be chosen for this system. Their design and R and D works for this synchrotron are reported. Furthermore, since longitudinal beam emittance will be controlled at injection and extraction by the rf manipulation because of alleviation of space charge effect, some simulation results for longitudinal motion by a particle tracking code are reported. (author)

  18. Research on feedback system of synchrotron accelerator

    International Nuclear Information System (INIS)

    It is a very complex problem to use feedback control system in synchrotron accelerator. Some scientists design feedback control system to make high energy beam stable in synchrotron accelerator, but it is very rare to see theoretically analysis feedback system in synchrotron accelerator by using new concept of control model. One new feedback control model is a fresh idea to discuss the feedback system more deeply. A topic about feedback control system discussed here will be useful for synchrotron accelerator design and operation. It is an good idea for some scientists and technician to continue study. (authors)

  19. Some application of synchrotron radiation

    International Nuclear Information System (INIS)

    Continuous tuneable wavelength in the range 0.01A < λ < 100A, high brilliance and parallelity of the beam are the outstanding properties for all applications of synchrotron radiation in condensed matter research. High angular and time resolution in synchrotron X-ray diffraction may be achieved. Powder Diffraction pattern with a full width at half maximum (FWHM) of Bragg reflections of ΔΘ - 0.02 display a resolution about five times better than laboratory equipment. Thus the investigation of structural phase transitions with only minor metric changes are feasible as well as direct determination of crystal structures from powder data. Registration of complete powder patterns in a few milliseconds opens the road to kinetic studies of crystallisation from glasses or melt and to structural phase transitions. The information from diffraction experiments which provide information on long range order is related to X-ray absorption experiments (XANES and EXAFS). X-ray absorption will provide information on the local environment of atoms (EXAFS) or on its electronic nature. Texture, strain and stress investigations with synchrotron radiation offer advantages as compared to laboratory X-ray work. The angular resolution is considerably improved due to the parallel beam geometry and the small beam size and the penetration depth may be varied by a factor of 6. Thus not only general orientation distribution functions but the anisotropy strain and complex stress behaviour at surfaces may be investigated in particular grains. Furthermore all kinds of surface studies at grazing incidence are performed with considerable advantage. (orig.)

  20. Synchrotron radiation XRF imaging techniques at the Brazil-LNLS

    International Nuclear Information System (INIS)

    Full text: The X-ray Fluorescence (XRF) analysis is a well-established method for quantitative multi-elemental bulk analysis. The use of a synchrotron radiation source allows constructing effective x-ray microprobes for study trace elements in small (nanogram) samples or their distributions with high spatial resolution. Since its operation, the XRF fluorescence beamline of the LNLS has offered to the user community several hard x-ray microprobes configurations to develop microscopic x-ray fluorescence analysis. The initially developed setup consisted of a fine conical monocapillary that allows condensing the polychromatic synchrotron beam down to an area of 20 microns in diameter. Novel strategies are now routinely in use or being installed at several synchrotron laboratories that require determining the 3D compositional structure of minor and trace elements in specific samples. These experimental setups take advantages of the high penetration depth of the x-rays (several orders of magnitude higher than the microbeam size). These alternative (microanalytical) methods are called x-ray fluorescence microtomography and confocal micro-XRF. This lecture intends to give a general description of all above configurations, showing their advantages/disadvantages and also pretends to show some specific applications carried out at the XRF Fluorescence beamline of the LNLS. (author)

  1. Synchrotron radiation XRF imaging techniques at the Brazil-LNLS

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Carlos A., E-mail: perez@lnls.br [X-ray Fluorescence and Absorption Group, Laboratorio Nacional de Luz Sincrotron, Campinas, SP (Brazil)

    2011-07-01

    Full text: The X-ray Fluorescence (XRF) analysis is a well-established method for quantitative multi-elemental bulk analysis. The use of a synchrotron radiation source allows constructing effective x-ray microprobes for study trace elements in small (nanogram) samples or their distributions with high spatial resolution. Since its operation, the XRF fluorescence beamline of the LNLS has offered to the user community several hard x-ray microprobes configurations to develop microscopic x-ray fluorescence analysis. The initially developed setup consisted of a fine conical monocapillary that allows condensing the polychromatic synchrotron beam down to an area of 20 microns in diameter. Novel strategies are now routinely in use or being installed at several synchrotron laboratories that require determining the 3D compositional structure of minor and trace elements in specific samples. These experimental setups take advantages of the high penetration depth of the x-rays (several orders of magnitude higher than the microbeam size). These alternative (microanalytical) methods are called x-ray fluorescence microtomography and confocal micro-XRF. This lecture intends to give a general description of all above configurations, showing their advantages/disadvantages and also pretends to show some specific applications carried out at the XRF Fluorescence beamline of the LNLS. (author)

  2. Progress in multielement silicon detectors for synchrotron XRF applications

    International Nuclear Information System (INIS)

    Multielement silicon strip detectors, in conjunction with integrated circuit pulse-processing electronics, offer an attractive alternative to conventional lithium-drifted silicon and high purity germanium detectors for high count rate, low noise synchrotron x-ray fluorescence applications. We have been developing these types of detectors specifically for low noise synchrotron applications, such as extended x-ray absorption fine structure spectroscopy, microprobe x-ray fluorescence and total reflection x-ray fluorescence. The current version of the 192-element detector and integrated circuit preamplifier, cooled to -25 degree C with a single-stage thermoelectric cooler, achieves an energy resolution of <200 eV FWHM (at 5.9 keV, 2 microseconds peaking time), and each detector element is designed to handle a ∼20 kHz count rate. The detector system will soon be completed to 64 channels using new IC amplifier chips, CAMAC ADCs, CAMAC histogramming modules, and Macintosh-based data acquisition software. We will report on the characteristics of this detector system, the characteristics of the next generation system (192 channels with IC ADCs), and the use of these detector systems in synchrotron XRF applications. copyright 1996 American Institute of Physics

  3. Surface Tension Gradients Induced by Temperature: The Thermal Marangoni Effect

    Science.gov (United States)

    Gugliotti, Marcos; Baptisto, Mauricio S.; Politi, Mario J.

    2004-01-01

    Surface tensions gradients were generated in a thin liquid film because of the local increase in temperature, for demonstration purposes. This is performed using a simple experiment and allows different alternatives for heat generation to be used.

  4. Computed tomography using synchrotron radiation

    International Nuclear Information System (INIS)

    X-ray computed tomography (CT) is a widely used method of obtaining cross-sectional views of objects. The high intensity, natural collimation, monochromaticity and energy tunability of synchrotron x-ray sources could potentially be used to provide CT images of improved quality. The advantages of these systems would be that images could be produced more rapidly with better spatial resolution and reduced beam artifacts. In addition, images, in some cases, could be acquired with elemental sensitivity. As a demonstration of the capability of such a system, CT images were obtained of four slices of an excised pig heart in which the arteries and the cardiac chambers were filled with an iodinated medium. Images were taken with incident x-rays tuned successively to energies just above and below the iodine K edge. Iodine specific images were obtained by logarithmically subtracting the low energy image data from the high energy data and then reconstructing the image. CT imaging using synchrotron radiation may become a convenient and non-destructive method of imaging samples difficult to study by other methods

  5. Microstructural gradients in thin hard coatings -- tailor-made

    DEFF Research Database (Denmark)

    Pantleon, Karen; Oettel, Heinrich

    1998-01-01

    ) alternating sputtering with and without substrate voltage and (c) pulsed bias voltage. On the basis of X-ray diffraction measurements, it is demonstrated that residual stress gradients and texture gradients can be designed tailor-made. Furthermore, results of microhardness measurements and scratch tests...

  6. High pressure and synchrotron radiation satellite workshop

    Energy Technology Data Exchange (ETDEWEB)

    Bass, J.; Guignot, N.; Morard, G.; Mezouar, M.; Andrault, D.; Bolfan-Casanova, N.; Sturhahn, W.; Daniel, I.; Reynard, B.; Simionovici, A.; Sanchez Valle, C.; Martinez, I.; Kantor, I.; Dubrovinsky, I.; Mccammon, C.; Dubrovinskaia, N.; Kurnosiv, A.; Kuznetsov, A.; Goncharenko, I.; Loubeyre, P.; Desgreniers, S.; Weck, G.; Yoo, C.S.; Iota, V.; Park, J.; Cynn, H.; Gorelli, F.; Toulemonde, P.; Machon, D.; Merlen, A.; San Miguel, A.; Amboage, M.; Aquilanti, G.; Mathon, O.; Pascarelli, S.; Itie, J.P.; Mcmillan, P.F.; Trapananti, A.; Di Cicco, A.; Panfilis, S. de; Filipponi, A.; Kreisel, J.; Bouvier, P.; Dkhil, B.; Chaabane, B.; Rosner, H.; Koudela, D.; Schwarz, U.; Handestein, A.; Hanfland, M.; Opahle, I.; Koepernik, K.; Kuzmin, M.; Mueller, K.H.; Mydosh, J.; Richter, M.; Hejny, C.; Falconi, S.; Lundegaard, L.F.; Mcmahon, M.I; Loa, I.; Syassen, K.; Wang, X.; Roth, H.; Lorenz, T.; Farber Daniel, I.; Antonangeli Daniele, I.; Krisch, M.; Badro, J.; Fiquet, G.; Occelli, F.; Mao, W.L.; Mao, H.K.; Eng, P.; Kao, C.C.; Shu, J.F.; Hemley, R.J.; Tse, J.S.; Yao, Y.; Deen, P.P.; Paolasini, I.; Braithwaite, D.; Kernavanois, N.; Lapertot, G.; Rupprecht, K.; Leupold, O.; Ponkratz, U.; Wortmann, G.; Beraud, A.; Krisch, M.; Farber, D.; Antonangeli, D.; Aracne, C.; Zarestky, J.L.; Mcqueeney, R.; Mathon, O.; Baudelet, F.; Decremps, F.; Itie, J.P.; Nataf, I.; Pascarelli, S.; Polian, A

    2006-07-01

    The workshop is dedicated to recent advances on science at high pressure at third generation synchrotron sources. A variety of experiments using synchrotron radiation techniques including X-ray diffraction, EXAFS (extended X-ray absorption fine structure), inelastic X-ray scattering, Compton scattering and Moessbauer spectroscopy of crystalline, liquid or amorphous samples, are reported. This document gathers the abstracts of the presentations.

  7. High pressure and synchrotron radiation satellite workshop

    International Nuclear Information System (INIS)

    The workshop is dedicated to recent advances on science at high pressure at third generation synchrotron sources. A variety of experiments using synchrotron radiation techniques including X-ray diffraction, EXAFS (extended X-ray absorption fine structure), inelastic X-ray scattering, Compton scattering and Moessbauer spectroscopy of crystalline, liquid or amorphous samples, are reported. This document gathers the abstracts of the presentations

  8. High-Intensity Synchrotron Radiation Effects

    CERN Document Server

    Suetsugu, Y

    2016-01-01

    Various effects of intense synchrotron radiation on the performance of particle accelerators, especially for storage rings, are discussed. Following a brief introduction to synchrotron radiation, the basic concepts of heat load, gas load, electron emission, and the countermeasures against these effects are discussed.

  9. Funding problems threaten Middle East's synchrotron

    CERN Multimedia

    McCabe, H

    1999-01-01

    Scientists will tour the Middle East to try to raise support for the Synchrotron radiation for Experimental Science and Applications in the Middle East project. The plan is to dismantle and move a decommissioned synchrotron from Berlin to the Middle East where scientists of any nationality would be able to use it (3 paragraphs).

  10. Alternative security

    International Nuclear Information System (INIS)

    This book contains the following chapters: The Military and Alternative Security: New Missions for Stable Conventional Security; Technology and Alternative Security: A Cherished Myth Expires; Law and Alternative Security: Toward a Just World Peace; Politics and Alternative Security: Toward a More Democratic, Therefore More Peaceful, World; Economics and Alternative Security: Toward a Peacekeeping International Economy; Psychology and Alternative Security: Needs, Perceptions, and Misperceptions; Religion and Alternative Security: A Prophetic Vision; and Toward Post-Nuclear Global Security: An Overview

  11. Synchrotron radiation - Applications in the earth sciences

    Science.gov (United States)

    Bassett, W. A.; Brown, G. E., Jr.

    Synchrotron-radiation sources and their characteristics are overviewed along with recent synchrotron-based research on earth materials and future earth-science applications utilizing the next generation of synchrotron-radiation sources presently under construction. Focus is placed on X-ray scattering studies of earth materials (crystalline and noncrystalline) under ambient conditions, diffraction studies of earth materials at high pressures and/or temperatures, spectroscopic studies, primarily X-ray absorption spectroscopy, and spatially resolved X-ray fluorescence studies of compositional variations in earth materials. It is noted that other synchrotron-based methods, such as X-ray tomography and topography may become important in characterizing earth materials, while soft X-ray/vacuum ultraviolet radiation from synchrotron sources can be applied to problems involving the structural environments of low-atomic-number elements and the characterization of surface reactions of minerals with liquids and gases.

  12. A Palmtop Synchrotron-like Radiation Source

    CERN Document Server

    Chen, Min; Luo, Ji; Liu, Feng; Sheng, Zheng-Ming; Zhang, Jie

    2015-01-01

    Synchrotron radiation sources are immensely useful tools for scientific researches and many practical applications. Currently, the state-of-the-art synchrotrons rely on conventional accelerators, where electrons are accelerated in a straight line and radiate in bending magnets or other insertion devices. However, these facilities are usually large and costly. Here, we propose a compact all-optical synchrotron-like radiation source based on laser-plasma acceleration either in a straight or in a curved plasma channel. With the laser pulse off-axially injected in a straight channel, the centroid oscillation of the pulse causes a wiggler motion of the whole accelerating structure including the trapped electrons, leading to strong synchrotron-like radiations with tunable spectra. It is further shown that a ring-shaped synchrotron is possible in a curved plasma channel. Due to the intense acceleration and bending fields inside plasmas, the central part of the sources can be made within palm size. With its potential...

  13. Protein Data Bank Depositions from Synchrotron Sources

    International Nuclear Information System (INIS)

    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 () 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

  14. Medical applications with synchrotron radiation in Japan

    International Nuclear Information System (INIS)

    In Japan, various medical applications of synchrotron X-ray imaging, such as angiography, monochromatic X-ray computed tomography (CT), radiography and radiation therapy, are being developed. In particular, coronary arteriography (CAG) is quite an important clinical application of synchrotron radiation. Using a two-dimensional imaging method, the first human intravenous CAG was carried out at KEK in May 1996; however, further improvements of image quality are required in clinical practice. On the other hand, two-dimensional aortographic CAG revealed canine coronary arteries as clearly as those on selective CAG, and coronary arteries less than 0.2 mm in diameter. Among applications of synchrotron radiation to X-ray CT, phase-contrast X-ray CT and fluorescent X-ray CT are expected to be very interesting future applications of synchrotron radiation. For actual clinical applications of synchrotron radiation, a medical beamline and a laboratory are now being constructed at SPring-8 in Harima

  15. Effects, causing intensification of synchrotron radiaiton beams

    International Nuclear Information System (INIS)

    Possibility of intensification of synchrotron radiation beams in optical and ultraviolet spectrum range by shift of generation range of the output synchrotron radiation beams from circle sections of electron orbit to the magnetic field of gaps, separating sections of the accelerator electromagnets is discussed. The degree of manifestation of the considered effects in synchrotrons for 0.6 and 7.5 GeV energy is evaluated. The results of their experimental investigati.on in the optical beam of the 0.6 GeV synchrotron radiation are given. The results obtained show that beam intensity in the gap centre between the magnet sections increases 3.2 times. The structure of beam intensity distribution improves simultaneously and vertical direction of radiation increases approximately 2 times. A conclusion is made on applicability of the described method for beam intensification of synchrotron radiation

  16. Laser textured surface gradients

    Science.gov (United States)

    Ta, Van Duong; Dunn, Andrew; Wasley, Thomas J.; Li, Ji; Kay, Robert W.; Stringer, Jonathan; Smith, Patrick J.; Esenturk, Emre; Connaughton, Colm; Shephard, Jonathan D.

    2016-05-01

    This work demonstrates a novel technique for fabricating surfaces with roughness and wettability gradients and their subsequent applications for chemical sensors. Surface roughness gradients on brass sheets are obtained directly by nanosecond laser texturing. When these structured surfaces are exposed to air, their wettability decreases with time (up to 20 days) achieving both spatial and temporal wettability gradients. The surfaces are responsive to organic solvents. Contact angles of a series of dilute isopropanol solutions decay exponentially with concentration. In particular, a fall of 132° in contact angle is observed on a surface gradient, one order of magnitude higher than the 14° observed for the unprocessed surface, when the isopropanol concentration increased from 0 to 15.6 wt%. As the wettability changes gradually over the surface, contact angle also changes correspondingly. This effect offers multi-sensitivity at different zones on the surface and is useful for accurate measurement of chemical concentration.

  17. Quaternion Gradient and Hessian

    OpenAIRE

    Xu, Dongpo; Mandic, Danilo P.

    2014-01-01

    The optimization of real scalar functions of quaternion variables, such as the mean square error or array output power, underpins many practical applications. Solutions often require the calculation of the gradient and Hessian, however, real functions of quaternion variables are essentially non-analytic. To address this issue, we propose new definitions of quaternion gradient and Hessian, based on the novel generalized HR (GHR) calculus, thus making possible efficient derivation of optimizati...

  18. Gradient Particle Magnetohydrodynamics

    OpenAIRE

    Maron, Jason L.; Howes, Gregory G.

    2001-01-01

    We introduce Gradient Particle Magnetohydrodynamics (GPM), a new Lagrangian method for magnetohydrodynamics based on gradients corrected for the locally disordered particle distribution. The development of a numerical code for MHD simulation using the GPM algorithm is outlined. Validation tests simulating linear and nonlinear sound waves, linear MHD waves, advection of magnetic fields in a magnetized vortex, hydrodynamical shocks, and three-dimensional collapse are presented, demonstrating th...

  19. Carbyne formation by synchrotron radiation

    CERN Document Server

    Kaito, C; Hanamoto, K; Sasaki, M; Kimura, S; Nakada, Tatsuya; Saitô, Y; Koike, C; Nakayama, Y

    2001-01-01

    Thin carbon films prepared by vacuum evaporation using the arc method were mounted on a standard electron microscope copper grid. They were irradiated by white synchrotron radiation (SR) beam by the use of cylindrical and toroidal mirrors. The irradiated film was examined using a high-resolution electron microscope. alpha and alpha+beta mixture carbyne crystals were grown in round and the elongated shapes. The round crystals were composed of 5-10 nm crystallites of a carbyne form. The elongated crystal grew into a single crystal 100 nm in size. The c-axes of both grown crystals were oblique to the film. The growth of the carbynes was discussed as being the result of nucleation due to graphite microcrystallites formed by SR beam irradiation.

  20. CERN/KEK: Very high accelerating gradients

    International Nuclear Information System (INIS)

    Full text: A world-wide effort is under way to develop linear electron-positron colliders so that physics experiments can be extended into a range of energies where circular machines (necessarily much larger than CERN's 27-kilometre LEP machine) would be crippled by synchrotron radiation. CERN is studying the feasibility of building a 2 TeV machine called CLIC powered not by individual klystrons, but by a high intensity electron 'drive' linac running parallel to the main linac (November 1990, page 7). This drive linac will itself be powered by similar superconducting cavities to those developed for LEP. A high gradient is an obvious design aim for any future high energy linear collider because it makes it shorter and therefore cheaper - the design figure for the CLIC machine is 80 MV/m. The CLIC study group has taken a significant step forward in demonstrating the technical feasibility of their machine by achieving peak and average accelerating gradients of 137 MV/m and 84 MV/m respectively in a short section of accelerating structure during high gradient tests at the Japanese KEK Laboratory last year. This result obtained within the framework of a CERN/KEK collaboration on linear colliders was obtained using a 20-cell accelerating section built at CERN using state-of the- art technology which served both as a model for CLIC studies as well as a prototype for the Japanese Linear Collider studies. The operating frequency of the model accelerating section is 2.6 times lower than the CLIC frequency but was chosen because a high power r.f. source and pulse compression scheme has been developed for this frequency at KEK. Testing CLIC models at 11.4 GHz is however more stringent than at 30 GHz because the chance of electrical breakdown increases as the frequency is lowered. This recent result clearly demonstrates that a gradient of 80 MV/m is feasible

  1. Study of a Rapid Cycling Synchrotron to replace the CERN PS Booster

    CERN Document Server

    Hanke, K; Angoletta, M E; Balhan, B; Bartmann, W; Benedikt, M; Borburgh, J; Bozzini, D; Carli, C; Dahlen, P; Dobers, T; Fitterer, M; Garoby, R; Gilardoni, S; Goddard, B; Hansen, J; Hermanns, T; Lopez-Hernandez, L A; Hourican, M; Jensen, S; Kosmicki, A; Meddahi, M; Mikulec, B; Newborough, A; Nonis, M; Olek, S; Paoluzzi, M; Pittet, S; Puccio, B; Raginel, V; Ruehl, I; Schönauer, H; Sermeus, L; Steerenberg, R; Tan, J; Tückmantel, J; Vretenar, M; Widorski, M

    2011-01-01

    CERN’s proton injector chain is undergoing a massive consolidation and upgrade program in order to deliver beams meeting the needs of the LHC Luminosity Upgrade. As an alternative to the upgrade of the existing Proton Synchrotron Booster (PSB), the construction of a Rapid Cycling Synchrotron (RCS) has been studied. This machine would replace the PSB and deliver beams to the LHC as well as to CERN’s rich fixed-target physics program. This paper summarizes the outcome of the feasibility study along with a tentative RCS design.

  2. Synchrotron applications to the earth sciences

    International Nuclear Information System (INIS)

    The earliest applications and development of conventional X-ray technologies at the beginning of the last century were strongly focused on earth science materials. Over the past 20 years minerals have continued to play a central role in the development of the new generations of synchrotron radiation techniques and the range of applications of synchrotron X-ray techniques to the study of the earth sciences has grown enormously. In this article we focus on the analytical possibilities arising from the application of synchrotron X-ray radiation as opposed to conventional cathode-tube based X-ray sources, using examples drawn from mineral characterisation and mineral processing

  3. Report of the Synchrotron Radiation Vacuum Workshop

    International Nuclear Information System (INIS)

    The Synchrotron Radiation Vacuum Workshop was held to consider two vacuum-related problems that bear on the design of storage rings and beam lines for synchrotron radiation facilities. These problems are gas desorption from the vacuum chamber walls and carbon deposition on optical components. Participants surveyed existing knowledge on these topics and recommended studies that should be performed as soon as possible to provide more definitive experimental data on these topics. This data will permit optimization of the final design of the Advanced Light Source (ALS) and its associated beam lines. It also should prove useful for other synchrotron radiation facilities as well

  4. High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics. Plasma Science and Fusion Center

    2016-07-12

    The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

  5. Gradient tabu search.

    Science.gov (United States)

    Stepanenko, Svetlana; Engels, Bernd

    2007-01-30

    This paper presents a modification of the tabu search called gradient tabu search (GTS). It uses analytical gradients for a fast minimization to the next local minimum and analytical diagonal elements of the Hessian to escape local minima. For an efficient blocking of already visited areas tabu regions and tabu directions are introduced into the tabu list (TL). Trials with various well-known test functions indicate that the GTS is a very promising approach to determine local and global minima of differentiable functions. Possible application areas could be optimization routines for force field parameters or conformational searches for large molecules. PMID:17186482

  6. High gradient superconducting quadrupoles

    International Nuclear Information System (INIS)

    Prototype superconducting quadrupoles with a 5 cm aperture and gradient of 16 kG/cm have been built and tested as candidate magnets for the final focus at SLC. The magnets are made from NbTi Tevatron style cable with 10 inner and 14 outer turns per quadrant. Quench performance and multipole data are presented. Design and data for a low current, high gradient quadrupole, similar in cross section but wound with a cable consisting of five insulated conductors are also discussed

  7. Study of radioactive materials with synchrotron radiation

    International Nuclear Information System (INIS)

    Synchrotron radiation brings 3 major improvements compared to other X-ray sources usually used in laboratories. Its high brilliance permits the study of size-reduced samples, the low divergency of the beam gives the possibility to increase the angular resolution of the diffractometer and the spectrum of the X-photons which is continuous, allows the experimenter to chose a particular wavelength. Synchrotron radiation is becoming an important tool to investigate radioactive materials particularly burnt nuclear fuels. Zircon is the corrosion product that appears on fuel clad during irradiation, the use of synchrotron radiation with the right wavelength and a discerning incidence angle has clearly shown a crystallographic change of the zircon induced by heavy ion irradiation. X-ray fluorescence induced by synchrotron radiation can give information on fission products which were till then undetected because of the lack of sensibility of previous methods. (A.C.)

  8. Panel backs next-generation synchrotron

    CERN Multimedia

    Service, R F

    1999-01-01

    A key federal panel recommended continued research into development of a fourth-generation synchrotron. It would be capable of creating x-ray pulses billions of times more intense than current designs (1 page).

  9. Applications of synchrotron radiation in Biophysics

    International Nuclear Information System (INIS)

    A short introduction to the generation of the synchrotron radiation is made. Following, the applications of such a radiation in biophysics with emphasis to the study of the hemoglobin molecule are presented. (L.C.)

  10. Simulation of synchrotron motion with rf noise

    International Nuclear Information System (INIS)

    The theoretical formulation is described that is behind an algorithm for synchrotron phase-space tracking with rf noise and some preliminary simulation results of bunch diffusion under rf noise obtained by actual tracking

  11. Spain in quandry over French synchrotron

    CERN Multimedia

    Bosch, X

    2000-01-01

    The French government has invited Spain to participate in the funding and operation of its proposed synchrotron Soleil. This could result though in the end of Spanish scientists' hopes for their own machine (1 page).

  12. National synchrotron light source VUV storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Blumberg, L.; Bittner, J.; Galayda, J.; Heese, R.; Krinsky, S.; Schuchman, J.; van Steenbergen, A.

    1979-01-01

    A 700 MeV electron storage ring designed for synchrotron radiation applications is described. Lattice and stability calculations are presented and the vacuum, correction and injection systems are discussed.

  13. Synchrotron radiation x-ray lithography

    International Nuclear Information System (INIS)

    Fine pattern fabrication technology has been supporting the progress in LSI integration. Synchrotron radiation X-ray lithography is considered the most promising path towards mass-production of LSIs a quarter micron or less in feature size. The present report first describes some fundamental characteristics of synchrotron radiation X-ray lithography, focusing on pattern replication methods, resolution (Fresnel diffraction, penumbral blur, mask contrast, and secondary electron range), process latitude, exposure field size, throughput, and overlay accuracy. The report also addresses test device fabrication conducted at NTT LSI Laboratories in Japan. Deep-submicron test device fabrication is carried out using synchrotron radiation lithography all of five exposure levels. The characteristics of the fabricated devices are found to be satisfactory. Synchrotron radiation X-ray lithography can potentially provide an excellent tool for fabricating fine patterns in the quarter micron range. (N.K.)

  14. Stanford Synchrotron Radiation Light Source (SSRL)

    Data.gov (United States)

    Federal Laboratory Consortium — The SSRL at SLAC National Accelerator Laboratory was built in 1974 to take and use for synchrotron studies the intense x-ray beams from the SPEAR storage ring that...

  15. Molecular photoemission studies using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Truesdale, C.M.

    1983-04-01

    The angular distributions of photoelectrons and Auger electrons were measured by electron spectroscopy using synchrotron radiation. The experimental results are compared with theoretical calculations to interpret the electronic behavior of photoionization for molecular systems.

  16. Molecular photoemission studies using synchrotron radiation

    International Nuclear Information System (INIS)

    The angular distributions of photoelectrons and Auger electrons were measured by electron spectroscopy using synchrotron radiation. The experimental results are compared with theoretical calculations to interpret the electronic behavior of photoionization for molecular systems

  17. National Synchrotron Light Source annual report 1988

    Energy Technology Data Exchange (ETDEWEB)

    Hulbert, S.; Lazarz, N.; Williams, G. (eds.)

    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)

  18. Synchrotrons are also devoted to society

    International Nuclear Information System (INIS)

    The ESRF and the SOLEIL synchrotrons are not only scientific instruments but also active players in the cultural and economic fields. This document gathers 6 short articles. The 2 first present the actions of SOLEIL and ESRS scientific teams towards the spreading of scientific knowledge in the public. The third article is dedicated to the uses of synchrotron radiation to the study of cultural objects to learn more about their fabrication, present state or the remedial actions that could be used to renovate them. The fourth and fifth articles present the contributions of ESRF and SOLEIL to the industrial world, in fact these contributions are not limited to the research field but also appear for quality assurance or the control of aging processes. Partnerships have been signed between both synchrotrons and enterprises to develop industrial products based on instrumentation or on the use of synchrotron radiation. The last article describes the procedure to have access to both facilities. (A.C.)

  19. Synchrotrons are also devoted to the society

    International Nuclear Information System (INIS)

    The ESRF and the SOLEIL synchrotrons are not only scientific instruments but also active players in the cultural and economic fields. This document gathers 6 short articles. The 2 first present the actions of SOLEIL and ESRS scientific teams towards the spreading of scientific knowledge in the public. The third article is dedicated to the uses of synchrotron radiation to the study of cultural objects to learn more about their fabrication, present state or the remedial actions that could be used to renovate them. The fourth and fifth articles present the contributions of ESRF and SOLEIL to the industrial world, in fact these contributions are not limited to the research field but also appear for quality assurance or the control of aging processes. Partnerships have been signed between both synchrotrons and enterprises to develop industrial products based on instrumentation or on the use of synchrotron radiation. The last article describes the procedure to have access to both facilities. (A.C.)

  20. Synchrotron radiation in inhomogeneous tokamak plasmas

    International Nuclear Information System (INIS)

    Synchrotron emission in a tokamak configuration with inhomogeneous plasma parameters is considered to investigate the effects of the temperature profile and vertical elongation on the radiation loss. Using the numerical solution of the transfer equation for ITER-like plasma parameters, several new results on the radiated energy in a Maxwellian plasma have been derived. In particular: (i) synchrotron loss is profile dependent, namely, at constant average thermal energy, the emitted radiation increases with the peak temperature, (ii) an analytical formula of the global loss in inhomogeneous tokamak plasmas with arbitrary vertical elongation is established, (iii) the maximum of the frequency emission spectrum is a linear function of the volume average temperature, (iiii) high frequency synchrotron radiation is entirely due to electrons with energy much greater than the thermal energy. The need for experimental investigations on synchrotron emission in present-day large tokamaks to determine the effect of reflections of the complex tokamak first wall is stressed

  1. Basic design for the synchrotron in the large synchrotron radiation facility, 1

    International Nuclear Information System (INIS)

    Synchrotron Radiation Facility Project Team in JAERI had tried to preliminarily design the injection system of Large Synchrotron Radiation Facility in the fiscal year 1988. Concentrating on the basic design for the booster synchrotron in this injection system, we describe the general method to design the separated function synchrotron which is used to accelerate high energy electrons or positrons. The content of this paper is founded on the physics of single particle motion. And in the next report we will discuss about the collective beam dynamics, the phenomena occurred during acceleration, and so on. (author)

  2. Early British synchrotrons, an informal history

    International Nuclear Information System (INIS)

    An historical account of the design and construction of early synchrotrons in the United Kingdom, based partly on personal reminiscences, is presented. Material is also drawn from archives at Birmingham and CERN. The document covers the period from plans for the world's first synchrotron at Malvern after the Second World War to work done at Harwell Laboratory for CERN in the period 1951-1953. (UK)

  3. Experimental demonstration of the KEK induction synchrotron

    International Nuclear Information System (INIS)

    Recent progress in the KEK induction synchrotron is presented. In the recent experiment, by using a newly developed induction acceleration system instead of radio-wave acceleration devices, a single proton bunch injected from the 500 MeV Booster ring and captured by the barrier bucket created by the induction step-voltages was accelerated to 6 GeV in the KEK proton synchrotron

  4. Commissioning experiences of the ALS booster synchrotron

    International Nuclear Information System (INIS)

    Installation of the ALS booster synchrotron proper was completed on April 30, 1991, and commissioning has just begun. Circulating beam around the booster was observed on the first day of operation, May 3, 1991. The beam was visible for about 400 turns. In this paper we describe the status and commissioning experience of the 1.5-GeV electron synchrotron accelerator. 14 refs., 2 figs., 4 tabs

  5. Manipulating the Gradient

    Science.gov (United States)

    Gaze, Eric C.

    2005-01-01

    We introduce a cooperative learning, group lab for a Calculus III course to facilitate comprehension of the gradient vector and directional derivative concepts. The lab is a hands-on experience allowing students to manipulate a tangent plane and empirically measure the effect of partial derivatives on the direction of optimal ascent. (Contains 7…

  6. Non scaling fixed field gradient accelerator design for proton and carbon therapy

    International Nuclear Information System (INIS)

    The Fixed Field Alternating Gradient (FFAG) accelerators became again a subject of great interest in many accelerator physics applications, after more than fifty years of their first appearance. The original FFAG's are the 'scaling' design where particle orbits during acceleration scale with momentum. In Japan a number of scaling FFAG's have been built, or are under construction. The original designs are proposed and used in many applications: proton acceleration in medical field for cancer therapy, electron acceleration for the low (food radiation, electron demonstration ring) and high energies (future e-RHIC 10 GeV), acceleration of muons (the 'PRISM'-project in Japan), proton acceleration for the AGS upgrade at Brookhaven National Laboratory, etc. There are many advantages of the scaling FFAG with respect to the today common use of synchrotrons, cyclotrons, or linear accelerators-linacs: the magnetic field is fixed, possibility of high repetition rate. Disadvantages of the scaling FFAG are the large required aperture and large circumference. This is due to the scaling law between the orbit and momentum and the relatively large opposite bending field requirement. This proposed non-scaling design had been extensively investigated in many respects. A European proposal to build a non-scaling FFAG electron demonstration ring is in progress. Recent international CYCLOTRON conference had dedicated time for the update on the FFAG acceleration. The non-scaling FFAG's should dramatically reduce required aperture and circumferences. If the fixed magnetic field produces the linear gradient, there is a tune variation during fast acceleration and resonances are a crossed. The small dispersion function and strong focusing in this design reduces the aperture size for almost an order of magnitude with respect to standard scaling FFAG design. We present one of the possible applications of the non-scaling proton and carbon cancer therapy FFAG accelerator. The cancer proton therapy

  7. High-intensity laser synchrotron x-ray source

    International Nuclear Information System (INIS)

    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 Light Source (LSLS) concept is still waiting for a convincing demonstration. Available at the BNL's Accelerator Test Facility (ATF), a high-brightness electron beam and the high-power C02 laser may be used as prototype LSLS brick stones. In a feasible demonstration experiment, 10-GW, 100-ps C02 laser beam will be brought to a head-on collision with a 10-ps, 0.5-nC, 70 MeV electron bunch. Flashes of well-collimated, up to 9.36-keV (∼ Angstrom) x-rays of 10-ps pulse duration, with a flux of ∼1019 photons/sec will be produced via linear Compton backscattering. The x-ray spectrum is tunable proportionally to a variable e-beam energy. A natural short-term extension of the proposed experiment would be further enhancement of the x-ray flux to a 1021-1022 photons/sec level, after the ongoing ATF CO2 laser upgrade to 1 TW peak power and electron bunch shortening to 3 ps. The ATF LSLS x-ray beamline, exceeding by orders of magnitude the peak fluxes attained at the National Synchrotron Light Source (NSLS) x-ray storage ring, may become attractive for certain users, e.g., for biological x-ray microscopy. In addition, a terawatt CO2 laser will enable harmonic multiplication of the x-ray spectrum via nonlinear Compton scattering

  8. Towards Establishing of National Centre of Synchrotron Radiation in Poland

    International Nuclear Information System (INIS)

    Hiroshima Synchrotron Radiation Center (HSRC) at University of Hiroshima based on synchrotron Aurora-2D manufactured by Sumitomo corp., or those adapted for Singapore Synchrotron Light Source at University of Singapore based on synchrotron Helios-2 by Oxford Instruments are discussed. Both Aurora-2D and Helios-2 sources base on the concept of racetrack type electron storage ring. The advantages of such solution is the low cost of initial installation, low maintenance cost and the completeness of the system delivered ready to use with injector microtron and with control systems. The drawbacks are: - the moderate ring performance resulting mainly from large beam emittance, - and small to none possibility of upgrading such device. Alternative solution taken into account is a design of dedicated compact storage ring in close cooperation with Berliner Electronenspeicherring Gesellschaft fuer Synchrotronstrahlung m. b. H (BESSY) construction team. The storage ring could be in fact made similar to the recently developed Metrology Light Source being currently designed in BESSY for Physikalisch Technische Bundestanstalt. In course of consultations with BESSY specialists it has been established that a 1 GeV ring could be designed within similar conceptual framework. The ring could accommodate several insertion devices including superconducting wiggler. The insertion devices could be manufactured at moderate cost at Budker Institute of Nuclear Physics in Novosibirsk as well as in BESSY. A preliminary time schedule and the budgetary requirements for planned Polish National Center of Synchrotron Radiation will also be presented

  9. Online Gradient Boosting

    OpenAIRE

    Beygelzimer, Alina; Hazan, Elad; Kale, Satyen; Luo, Haipeng

    2015-01-01

    We extend the theory of boosting for regression problems to the online learning setting. Generalizing from the batch setting for boosting, the notion of a weak learning algorithm is modeled as an online learning algorithm with linear loss functions that competes with a base class of regression functions, while a strong learning algorithm is an online learning algorithm with convex loss functions that competes with a larger class of regression functions. Our main result is an online gradient b...

  10. Gradient structures in hardmetals

    International Nuclear Information System (INIS)

    Functionally graded materials enable combinations of properties like hardness and toughness that can not be achieved with homogeneous materials. The formation of gradients in tungsten carbides correlates with the migration of binder which is caused by differences in the composition of the green body, gas-phase treatment during sintering or the mean particle size and particle-size distribution of the hard phase. In order to examine the gradient formation fracture bars were made of differently fine-grained WC powders and variable additions of Co and carbon black. Beside homogeneous samples two-layer samples were manufactured by step-wise pressing of powders with different composition and/or grain size. The densification behavior of the green bodies and the magnetic and mechanical properties of the sintered compacts were measured. On two-layer samples with full density the concentration profiles of Co, C and W was determined parallel to the pressing direction over the entire sample height (≤ 10 mm) by ESMA. Additionally, hardness and fracture toughness were measured along this line. Differences in cobalt contents are rapidly homogenized in liquid-phase sintering. But large Co gradients can be generated by differences in particle sizes of the hard phase, the non-metal content (carbon, oxygen) and impurities in the ppm range (influence of the wetting and solubility conditions). After sintering the binder content of the finer grained layer is generally higher than in the coarser layer independent of the starting composition. In two-layer samples Co gradients up to 10 mm in thickness and hardness differences to 500 units (HV10) could be produced. (author)

  11. Energy in density gradient

    OpenAIRE

    Vranjes, J.; Kono, M

    2015-01-01

    Inhomogeneous plasmas and fluids contain energy stored in inhomogeneity and they naturally tend to relax into lower energy states by developing instabilities or by diffusion. But the actual amount of energy in such inhomogeneities has remained unknown. In the present work the amount of energy stored in a density gradient is calculated for several specific density profiles in a cylindric configuration. This is of practical importance for drift wave instability in various plasmas, and in partic...

  12. Conjugate gradient method

    Czech Academy of Sciences Publication Activity Database

    Segeth, Karel

    Liberec : Technická univerzita v Liberci, 2006, s. 335-341. ISBN 80-7372-055-8. [International Conference Presentation of Mathematics ICPM ´05. Liberec (CZ), 20.09.2005-23.09.2005] R&D Projects: GA ČR(CZ) GA201/04/1503 Institutional research plan: CEZ:AV0Z10190503 Keywords : linear algebraic system * conjugate gradient method * preconditioning Subject RIV: BA - General Mathematics

  13. Beam focusing limitation from synchrotron radiation in two dimensions

    Science.gov (United States)

    Blanco, O. R.; Tomás, R.; Bambade, P.

    2016-02-01

    The Oide effect considers the synchrotron radiation in the final focusing quadrupole, and it sets a lower limit on the vertical beam size at the interaction point, particularly relevant for high-energy linear colliders. The theory of the Oide effect was derived considering only the second moment of the radiation in the focusing plane of the magnet. This article addresses the theoretical calculation of the radiation effect on the beam size considering the first and second moments of the radiation and both focusing and defocusing planes of the quadrupole. The effect for a Gaussian beam is referred to as 2D-Oide; however, an alternative beam size figure is given that could represent better the effect on the minimum achievable βy* . The CLIC 3 TeV final quadrupole (QD0) and beam parameters are used to compare the theoretical results from the Oide effect and the 2D-Oide effect with particle tracking in placet. The 2D-Oide effect is demonstrated to be important, as it increases by 17% the contribution to the beam size. Further insight into the aberrations induced by the synchrotron radiation opens the possibility to partially correct the 2D-Oide effect with octupole magnets. A beam size reduction of 4% is achieved in the simplest configuration, using a single octupole.

  14. Synchrotron radiation applications in medical research

    International Nuclear Information System (INIS)

    The medical projects employing synchrotron radiation as discussed in this paper are, for the most part, still in their infancies and no one can predict the direction in which they will develop. Both the basic research and applied medical programs are sure to be advanced at the new facilities coming on line, especially the ESRF and Spring- 8. However, success is not guaranteed. There is a lot of competition from advances in conventional imaging with the development of digital angiography, computed tomography, functional magnetic resonance imaging and ultrasound. The synchrotron programs will have to provide significant advantages over these modalities in order to be accepted by the medical profession. Advances in image processing and potentially the development of compact sources will be required in order to move the synchrotron developed imaging technologies into the clinical world. In any event, it can be expected that the images produced by the synchrotron technologies will establish ''gold standards'' to be targeted by conventional modalities. A lot more work needs to be done in order to bring synchrotron radiation therapy and surgery to the level of human studies and, subsequently, to clinical applications

  15. Metrology of reflection optics for synchrotron radiation

    International Nuclear Information System (INIS)

    Recent years have seen an almost explosive growth in the number of beam lines on new and existing synchrotron radiation facilities throughout the world. The need for optical components to utilize the unique characteristics of synchrotron radiation has increased accordingly. Unfortunately, the technology to manufacture and measure the large, smooth, exotic optical surfaces required to focus and steer the synchrotron radiation beam has not progressed as rapidly as the operational demands on these components. Most companies do not wish to become involved with a project that requires producing a single, very expensive, aspheric optic with surface roughness and figure tolerances that are beyond their capabilities to measure. This paper will review some of the experiences of the National Synchrotron Light Source in procuring grazing incidence optical components over the past several years. We will review the specification process - how it is related to the function of the optic, and how it relates to the metrology available during the manufacturing process and after delivery to the user's laboratory. We will also discuss practical aspects of our experience with new technologies, such as single point diamond turning of metal mirrors and the use of SiC as a mirror material. Recent advances in metrology instrumentation have the potential to move the measurement of surface figure and finish from the research laboratory into the optical shop, which should stimulate growth and interest in the manufacturing of optics to meet the needs of the synchrotron radiation user community

  16. High gradient quadrupoles for low emittance storage rings

    Science.gov (United States)

    Le Bec, G.; Chavanne, J.; Benabderrahmane, C.; Farvacque, L.; Goirand, L.; Liuzzo, S.; Raimondi, P.; Villar, F.

    2016-05-01

    High gradient quadrupoles are key components for the coming generation of storage ring based light sources. The typical specifications of these magnets are: almost 100 T /m gradient, half a meter long, and a vertical aperture for the extraction of the x-ray beam. This paper presents the preparation work done at the European Synchrotron Radiation Facility, from the design to the manufacture and measurements of a prototype. It demonstrates the feasibility of such magnets. Different aspects of magnet engineering are discussed, including the study of the main scale factors and the preliminary design, the pole shaping, the impact of mechanical errors, and the magnetic measurements of a prototype with a stretched-wire system.

  17. An alternative solution to the gamma-ray Gradient problem

    CERN Document Server

    Gaggero, Daniele; Grasso, Dario; Maccione, Luca

    2011-01-01

    The Fermi-LAT collaboration recently confirmed EGRET finding of a discrepancy between the observed longitudinal profile of gamma-ray diffuse emission from the Galaxy and that computed with GALPROP assuming that cosmic rays are produced by Galactic supernova remnants. The accurate Fermi-LAT measurements make this anomaly hardly explainable in terms of conventional diffusion schemes. Here we use DRAGON numerical diffusion code to implement a physically motivated scenario in which the diffusion coefficient is spatially correlated to the source density. We show that under those conditions we are able to reproduce the observed flat emissivity profile in the outer Galaxy with no need to change the source term, the diffusion halo height, or the CO-H2 conversion factor (XCO) with respect to their preferred values/distributions. We also show that our models are compatible with gamma-ray longitudinal profiles measured by Fermi-LAT, and still provide a satisfactory fit of all observed secondary-to-primary ratios, such a...

  18. Paraxial Green's functions in Synchrotron Radiation theory

    CERN Document Server

    Geloni, G; Schneidmiller, E; Yurkov, M; Geloni, Gianluca; Saldin, Evgeni; Schneidmiller, Evgeni; Yurkov, Mikhail

    2005-01-01

    This work contains a systematic treatment of single particle Synchrotron Radiation and some application to realistic beams with given cross section area, divergence and energy spread. Standard theory relies on several approximations whose applicability limits and accuracy are often forgotten. We begin remarking that on the one hand, a paraxial approximation can always be applied without loss of generality and with ultra relativistic accuracy. On the other hand, dominance of the acceleration field over the velocity part in the Lienard-Wiechert expressions is not always granted and constitutes a separate assumption, whose applicability is discussed. Treating Synchrotron Radiation in paraxial approximation we derive the equation for the slow varying envelope function of the Fourier components of the electric field vector. Calculations of Synchrotron Radiation properties performed by others showed that the phase of the Fourier components of the electric field vector differs from the phase of a virtual point sourc...

  19. Chemical applications of synchrotron radiation: Workshop report

    International Nuclear Information System (INIS)

    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 field 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

  20. Chemical applications of synchrotron radiation: Workshop report

    Energy Technology Data Exchange (ETDEWEB)

    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 field 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.

  1. New extreme synchrotron BL Lac objects

    International Nuclear Information System (INIS)

    We report on the BeppoSAX observations of four 'extreme' BL Lacs, selected to have high synchrotron peak frequencies. All have been detected also in the PDS band. For 1ES 0120+340, PKS 0548-322 and H 2356-309 the spectrum is well fitted by a convex broken power-law, thus locating the synchrotron peak around 1-4 keV. 1ES 1426+428 presents a flat energy spectral index (αx=0.92) up to ∼100 keV, thus constraining the synchrotron peak to lie near or above that value. For their extreme properties, all sources could be strong TeV emitters

  2. Third-generation synchrotron light sources

    International Nuclear Information System (INIS)

    X rays are a powerful probe of matter because they interact with electrons in atoms, molecules, and solids. They are commonly produced by relativistic electrons or positrons stored in a synchrotron. Recent advances in technology are leading to the development of a new third generation of synchrotron radiation sources that produce vacuum-ultraviolet and x-ray beams of unprecedented brightness. These new sources are characterized by a very low electron-beam emittance and by long straight sections to accommodate permanent-magnet undulators and wigglers. Several new low-energy light sources, including the Advanced Light Source, presently under construction at the Lawrence Berkeley Laboratory, and ELETTRA, presently being constructed in Trieste, will deliver the world's brightest synchrotron radiation in the VUV and soft x-ray regions of the spectrum. Applications include atomic and molecular physics and chemistry, surface and materials science, microscopy, and life sciences

  3. High density THz frequency comb produced by coherent synchrotron radiation

    CERN Document Server

    Tammaro, S; Roy, P; Lampin, J -F; Ducournau, G; Cuisset, A; Hindle, F; Mouret, G

    2014-01-01

    Frequency combs (FC) have radically changed the landscape of frequency metrology and high-resolution spectroscopy investigations extending tremendously the achievable resolution while increasing signal to noise ratio. Initially developed in the visible and near-IR spectral regions, the use of FC has been expanded to mid-IR, extreme ultra-violet and X-ray. Significant effort is presently dedicated to the generation of FC at THz frequencies. One solution based on converting a stabilized optical frequency comb using a photoconductive terahertz emitter, remains hampered by the low available THz power. Another approach is based on active mode locked THz quantum-cascade-lasers providing intense FC over a relatively limited spectral extension. Alternatively, here we show that dense powerful THz FC is generated over one decade of frequency by coherent synchrotron radiation (CSR). In this mode, the entire ring behaves in a similar fashion to a THz resonator wherein electron bunches emit powerful THz pulses quasi-synch...

  4. Working point and resonance studies at the CERN Proton Synchrotron

    CERN Document Server

    Huschauer, Alexander; Steerenberg, Rende

    The Proton Synchrotron (PS) is the oldest yet the most versatile particle accelerator operating at CERN. Having accelerated a multitude of different particle species within the last five decades, it is today used to define the longitudinal structure of the proton beams going into collision in the Large Hadron Collider (LHC), and thus constitutes an integral part of the LHC injector chain. Around 2020 the LHC will be subject to an upgrade to significantly increase the number of collisions at the interaction points. The beam parameters demanded by the High Luminosity LHC (HL-LHC) will, as a result, require substantial improvements of the pre-accelerators, which are currently being studied within the LHC Injectors Upgrade (LIU) project. The increase of luminosity will be accompanied by an increase of beam intensity, which might result in instabilities appearing on the injection flat bottom of the PS. Transverse Head-Tail instabilities have already been observed on operational LHC beams and an alternative stabili...

  5. Synchrotron environmental laboratory (SUL) at Anka

    International Nuclear Information System (INIS)

    A research facility dedicated to environmental/geochemical research, the Synchrotron Environmental Laboratory (SUL), is planned to be installed and operated at ANKA. ANKA is the new synchrotron facility at the Research Centre Karlsruhe (FZK), Karlsruhe, Germany. ANKA is now in commissioning and planning operations for the fall of 2000. As the Institute for Nuclear Waste Disposal (INE) at FZK conducts a vigorous synchrotron-based research programme, INE was instrumental in the original impetus for installing such a facility at ANKA. These research activities at INE concentrate on actinide speciation in nuclear waste forms, geological media and geochemical model systems. In order for INE to direct their synchrotron research activities to ANKA, equipment and licensing required for performing experiments on actinide-containing samples is required. One great advantage of performing experiments on actinide-containing samples at ANKA is that the INE radiological laboratories lie in the near vicinity of the facility. This will minimise transport hazards and costs and allow experiments to be performed on samples whose characteristics may change with time. Experiments on radioactive samples with activities below the exemption level, according to German regulations, will be possible at ANKA at the start of operations. Licensing for work on higher levels of activity will be applied for in the future. The decades of experience in radiological work at FZK will facilitate development of procedure and equipment as prerequisites to licensing. A consortium of synchrotron radiation-user groups with environmental research interests has specified their requirements and needs for this facility. This scientific case serves as the foundation for the SUL design and is the basis for an application for federal funding. The SUL design reflects the heterogeneity and complexity of challenges facing researchers in the environmental/geochemical sciences. X-ray absorption fine structure (XAFS

  6. Generalized quasi Yamabe gradient solitons

    OpenAIRE

    Neto, Benedito Leandro; de Oliveira, Hudson Pina

    2016-01-01

    We prove that a nontrivial complete generalized quasi Yamabe gradient soliton (M; g) must be a quasi Yamabe gradient soliton on each connected component of M and that a nontrivial complete locally conformally at generalized quasi Yamabe gradient soliton has a special warped product structure.

  7. Color gradient background oriented schlieren imaging

    Science.gov (United States)

    Mier, Frank Austin; Hargather, Michael

    2015-11-01

    Background oriented schlieren (BOS) imaging is a method of visualizing refractive disturbances through the comparison of digital images. By comparing images with and without a refractive disturbance visualizations can be achieved via a range of image processing methods. Traditionally, backgrounds consist of random distributions of high contrast speckle patterns. To image a refractive disturbance, a digital image correlation algorithm is used to identify the location and magnitude of apparent pixel shifts in the background pattern. Here a novel method of using color gradient backgrounds is explored as an alternative. The gradient background eliminates the need to perform an image correlation between the two digital images, as simple image subtraction can be used to identify the location, magnitude, and direction of the image distortions. This allows for quicker processing. Two-dimensional gradient backgrounds using multiple colors are shown. The gradient backgrounds are demonstrated to provide quantitative data limited only by the camera's pixel resolution, whereas speckle backgrounds limit resolution to the size of the random pattern features and image correlation window size. Additional results include the use of a computer screen as a background.

  8. Basic technology of synchrotron power supply

    International Nuclear Information System (INIS)

    The thyristor power supply for a synchrotron magnet system is described. An analysis of the magnet strings, power electronics and control system is carried out with a bird's-eye view, however the fundamental description is appeared. It assumes a student and an engineer in fields concepts, which can be the electronics designing in related fields, and a background in Laplas transforms. It presents an example of power supply, which is developed for the synchrotron- cooler ring TARN II at Institute for Nuclear Study, Univ. of Tokyo. (author)

  9. Bunch heating by coherent synchrotron radiation

    International Nuclear Information System (INIS)

    The authors discuss here effects which define the steady-state rms energy spread of a microbunch in a storage ring. It is implied that the longitudinal microwave instability is controlled by low α lattice. In this case the coherent synchrotron radiation, if exists, may be the main factor defining the bunch temperature. Another effect comes from the fact that a nonlinear momentum compaction of such lattices makes Haissinskii equation not applicable, and the coherent synchrotron radiation may effect not only bunch lengthening but the energy spread as well

  10. 12 Experimental Techniques at Synchrotron Lightsource Beamlines

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Peter L [US Department of Energy Office of Science Office Basic Energy Sciences; Rhyne, James J [US Department of Energy Office of Science Office of Basic Energy Sciences

    2015-01-01

    The unique properties of synchrotron radiation are its continuous spectrum, high flux and brightness, and high coherence, which make it an indispensable tool in the exploration of matter. The wavelengths of the emitted photons span a range of dimensions from the atomic level to biological cells, thereby providing incisive probes for advanced research in materials science, physical and chemical sciences, metrology, geosciences, environmental sciences, biosciences, medical sciences, and pharmaceutical sciences. The features of synchrotron radiation are especially well matched to the needs of nanoscience.

  11. Atomic collision experiments using pulsed synchrotron radiation

    International Nuclear Information System (INIS)

    High intensity and continuous nature of the synchrotron radiation are the properties that are fundamentally important for studies of some atomic collision experiments, and many processes have been investigated by using these characteristics. However, so far the property that the radiation is highly polarized and pulsed in time has not been exploited significantly in atomic physics. As an example of the atomic processes relevant to such polarized and pulsed features of the synchrotron radiation, collisions involving optically-allowed excited atoms and molecules will be presented. (author)

  12. Synchrotron characterization of functional tin dioxide nanowires

    International Nuclear Information System (INIS)

    Wire-like crystals of tin dioxide were synthesized by a gas-transport technique. The wires, of mainly nanometric diameters, were characterized by spectroscopy and microscopy techniques with the use of highly brilliant and intense synchrotron radiation. We studied the influence of the surface chemical state and the oxygen vacancies on the atomic and electronic structure of the nanowires. The surface of the nanowires is covered by a few nanometers of tin suboxides. The lack of oxygen over the surface layers leads to specific sub-zone formation in a gap, as shown by synchrotron studies

  13. Berkeley Lab's ALS generates femtosecond synchrotron radiation

    International Nuclear Information System (INIS)

    A Lawrence Berkeley National Laboratory team has succeeded in generating 300 fs pulses of synchrotron radiation at the ALS synchrotron radiation machine. Although this proof-of-principle experiment made use of visible light on a borrowed beamline, the laser 'time-slicing' technique at the heart of the demonstration will soon be applied in a new bend-magnet beamline that was designed specially for the production of femtosecond pulses of X-rays to study long-range and local order in condensed matter with ultrafast time resolution. An undulator beamline based on the same technique has been proposed that will dramatically increase the flux and brightness

  14. Synchrotron characterization of functional tin dioxide nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Domashevskaya, E. P., E-mail: ftt@phys.vsu.ru; Chuvenkova, O. A.; Turishchev, S. Yu. [Voronezh State University, Voronezh (Russian Federation)

    2015-12-31

    Wire-like crystals of tin dioxide were synthesized by a gas-transport technique. The wires, of mainly nanometric diameters, were characterized by spectroscopy and microscopy techniques with the use of highly brilliant and intense synchrotron radiation. We studied the influence of the surface chemical state and the oxygen vacancies on the atomic and electronic structure of the nanowires. The surface of the nanowires is covered by a few nanometers of tin suboxides. The lack of oxygen over the surface layers leads to specific sub-zone formation in a gap, as shown by synchrotron studies.

  15. Nonlinear Conjugate Gradient Methods

    Czech Academy of Sciences Publication Activity Database

    Lukšan, Ladislav; Vlček, Jan

    Praha: Matematický ústav AV ČR, v.v.i, 2015 - (Chleboun, J.; Přikryl, P.; Segeth, K.; Šístek, J.; Vejchodský, T.), s. 130-135 ISBN 978-80-85823-64-6. [Programs and Algorithms of Numerical Mathematics /17./. Dolní Maxov (CZ), 08.06.2014-13.06.2014] Institutional support: RVO:67985807 Keywords : minimization * nonlinear conjugate gradient methods * comparison of methods * efficiency of methods Subject RIV: BA - General Mathematics http://dml.cz/handle/10338.dmlcz/702674

  16. Preliminar plan of a machine for the synchrotron radiation production

    International Nuclear Information System (INIS)

    A preliminar plan, with all the technical specifications, for the construction of a machine for the synchrotron radiation production to be done by the National Synchrotron Radiation Laboratory in Brazil is presented. (L.C.)

  17. Source size conserving broad band monochromators of fixed exit geometry for high energy synchrotron radiation

    International Nuclear Information System (INIS)

    The degradation of the effective source size by energy tunable, fixed exit, broad band monochromators for high energy synchrotron radiation (40-100 keV) is measured to be below 2 μrad. Two monochromator schemes consisting of either two bent Laue crystals or two SiGe gradient crystals in a non-dispersive setting are characterized. The relative energy bandwidth is about 0.1% and reflectivities are above 80%. The source size broadening and band widths are found to be in agreement with predictions by a kinematical model

  18. Atomic physics research with synchrotron radiation

    International Nuclear Information System (INIS)

    Applications of synchrotron radiation to research in high-energy atomic physics are summarized. These lie in the areas of photoelectron spectrometry, photon scattering, x-ray absorption spectroscopy, time-resolved measurements, resonance spectroscopy and threshold excitation, and future, yet undefined studies

  19. Materials science and technology by synchrotron radiation

    International Nuclear Information System (INIS)

    In the present paper, features of the Photon Factory, a facility for synchrotron research installed at the National Laboratory for High Energy Physics in Japan, are outlined, and then the impact of the advent of synchrotron radiation is discussed in relation to its outcome during the past seven years. Prospects for future development of synchrotron radiation are also presented. The facility consists of an injector linac to accelerate electrons up to 2.5 GeV and a ring to store the accelerated electrons in a closed orbit. In the Photon Factory, a 400m-long linac has been constructed for use as injector for both the Photon Factory and the TRISTAN electron-positron collider. The storage ring is operated at the same electron energy of 2.5 GeV. The present report also describes some applications of synchrotron radiation, focusing on spectroscopy (X-ray fluorescence technique and time-resolved X-ray absorption spectroscopy), diffraction and scattering (surface structure studies and protein crystallography), and photo-chemical processing. (N.K.)

  20. The Synchrotron Radiation for Steel Research

    Directory of Open Access Journals (Sweden)

    Piyada Suwanpinij

    2016-01-01

    Full Text Available The synchrotron X-ray radiation is a great tool in materials characterization with several advantageous features. The high intensity allows clear interaction signals and high energy of X-ray yields higher sampling volume. The samples do not need extra preparation and the microstructure is therefore not affected. With the tunability of the X-ray energy, a large range of elements and features in the samples can be investigated by different techniques, which is a significant difference between a stand-alone X-ray tube and synchrotron X-ray. Moreover, any experimental equipment can be installed through which the synchrotron beam travels. This facilitates the so-called in situ characterization such as during heat treatment, hot deformation, chemical reaction or welding. Although steel which possesses rather high density requires very high energy X-ray for large interaction volume, lower energy is still effective for the investigation of local structure of nanoconstituents. This work picks up a couple examples employing synchrotron X-ray for the characterization of high strength steels. The first case is the quantification of precipitates in high strength low alloyed (HSLA steel by X-ray absorption spectroscopy. The other case is the in situ X-ray diffraction for phase fraction and carbon partitioning in multiphase steels such as transformation induced plasticity (TRIP steel.

  1. Synchrotron radiation and free electron laser activities in Novosibirsk

    International Nuclear Information System (INIS)

    The results of studies realized in the Siberian synchrotron radiation centre within the frameworks of wide program of synchrotron radiation and free electron laser research are summarized. The technical information on the VEPP-2M, VEPP-3 and VEPP-4M storage rings used as synchrotron radiation sources is given. 10 refs.; 8 figs.; 12 tabs

  2. Basic design for the RF system of the synchrotron in the large synchrotron radiation facility (SPring-8)

    International Nuclear Information System (INIS)

    The large synchrotron radiation facility (SPring-8) is planned to be built at Nishiharima in Hyogo-ken. This paper describes basic designs, its philosophy and specifications of the ratio frequency system in the synchrotron. (author)

  3. Computerized microtomography using synchrotron radiation from the NSLS [National Synchrotron Light Source

    International Nuclear Information System (INIS)

    Results of microtomography experiments that employ filtered radiation from the National Synchrotron Light Source X-26 Microprobe beam line are presented. These experiments have yielded images of a freeze-dried caterpillar with a spatial resolution of the order of 30 μm and show that the limit on the spatial resolution with the present apparatus will be 1 to 10 μm. Directions for improvement in synchrotron microtomography techniques and some possible applications are discussed. 14 refs., 3 figs

  4. Generalized conjugate gradient squared

    Energy Technology Data Exchange (ETDEWEB)

    Fokkema, D.R.; Sleijpen, G.L.G. [Utrecht Univ. (Netherlands)

    1994-12-31

    In order to solve non-symmetric linear systems of equations, the Conjugate Gradient Squared (CGS) is a well-known and widely used iterative method. In practice the method converges fast, often twice as fast as the Bi-Conjugate Gradient method. This is what you may expect, since CGS uses the square of the BiCG polynomial. However, CGS may suffer from its erratic convergence behavior. The method may diverge or the approximate solution may be inaccurate. BiCGSTAB uses the BiCG polynomial and a product of linear factors in an attempt to smoothen the convergence. In many cases, this has proven to be very effective. Unfortunately, the convergence of BiCGSTAB may stall when a linear factor (nearly) degenerates. BiCGstab({ell}) is designed to overcome this degeneration of linear factors. It generalizes BiCGSTAB and uses both the BiCG polynomial and a product of higher order factors. Still, CGS may converge faster than BiCGSTAB or BiCGstab({ell}). So instead of using a product of linear or higher order factors, it may be worthwhile to look for other polynomials. Since the BiCG polynomial is based on a three term recursion, a natural choice would be a polynomial based on another three term recursion. Possibly, a suitable choice of recursion coefficients would result in method that converges faster or as fast as CGS, but less erratic. It turns out that an algorithm for such a method can easily be formulated. One particular choice for the recursion coefficients leads to CGS. Therefore one could call this algorithm generalized CGS. Another choice for the recursion coefficients leads to BiCGSTAB. It is therefore possible to mix linear factors and some polynomial based on a three term recursion. This way one may get the best of both worlds. The authors will report on their findings.

  5. Polyakov loop renormalization with gradient flow

    OpenAIRE

    Petreczky, Peter; Schadler, Hans-Peter

    2015-01-01

    We propose to use the gradient flow for the renormalization of Polyakov loops in various representations. We study Polyakov loops in 2+1 flavor QCD using the HISQ action and lattices with temporal extents $N_\\tau$=6, 8, 10 and 12 in various representations, including fundamental, sextet, adjoint, decuplet, 15-plet and 27-plet. This alternative renormalization procedure allows for the renormalization over a large temperature range from $T$=100 MeV - 800 MeV, with small errors not only for the ...

  6. Polyakov loop renormalization with gradient flow

    CERN Document Server

    Petreczky, Peter

    2015-01-01

    We propose to use the gradient flow for the renormalization of Polyakov loops in various representations. We study Polyakov loops in 2+1 flavor QCD using the HISQ action and lattices with temporal extents $N_\\tau$=6, 8, 10 and 12 in various representations, including fundamental, sextet, adjoint, decuplet, 15-plet and 27-plet. This alternative renormalization procedure allows for the renormalization over a large temperature range from $T$=100 MeV - 800 MeV, with small errors not only for the fundamental, but also for the higher representations of the Polyakov loop. We discuss the results of this procedure and Casimir scaling of the Polyakov loop.

  7. The profile of the electron beam in the PTB synchrotron, and its influence on radiometric measurements with synchrotron radiation

    International Nuclear Information System (INIS)

    A simple method is described to determine the beam profile in an electron synchrotron; the measured results are compared with calculated values. Moreover, the influence of synchrotron- and betatron-oscillations on synchrotron radiation measurements is discussed, and a method is given to correct this. (orig.)

  8. Rigidity of gradient Ricci Solitons

    OpenAIRE

    Petersen, Peter; Wylie, William

    2007-01-01

    We define a gradient Ricci soliton to be rigid if it is a flat bundle $% N\\times_{\\Gamma}\\mathbb{R}^{k}$ where $N$ is Einstein. It is known that not all gradient solitons are rigid. Here we offer several natural conditions on the curvature that characterize rigid gradient solitons. Other related results on rigidity of Ricci solitons are also explained in the last section.

  9. Alternative Treatments

    Science.gov (United States)

    ... Find your chapter: search by state Home > Alzheimer's Disease > Treatments > Alternative Treatments Overview What Is Dementia? What Is Alzheimer's? Younger/Early Onset Facts and Figures Know the 10 Signs Stages Inside the Brain: ...

  10. Gradient boosting machines, a tutorial.

    Science.gov (United States)

    Natekin, Alexey; Knoll, Alois

    2013-01-01

    Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods with a strong focus on machine learning aspects of modeling. A theoretical information is complemented with descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. Three practical examples of gradient boosting applications are presented and comprehensively analyzed. PMID:24409142

  11. Gradient Boosting Machines, A Tutorial

    Directory of Open Access Journals (Sweden)

    Alexey eNatekin

    2013-12-01

    Full Text Available Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. A set of practical examples of gradient boosting applications are presented and comprehensively analyzed.

  12. Oak Ridge Synchrotron Organization for Advanced Research (ORSOAR)

    International Nuclear Information System (INIS)

    This report briefly describes the research highlights, publications, and work in progress for the Oak Ridge Synchrotron Organization for Advanced Research. Among the research highlights of this reporting period are the following: We have advanced the technique for depth-profiling strain distributions in materials. We continued our studies of depth-profiling of polished and severely grounded, fully stabilized zirconia using long wavelength x-rays and shallow glancing angles, strain gradients near the surface approached maximum compressive strains of 4% but dropped rapidly as a function of depth. Strain profiles in thin (∼900Ao) films of GaAs grown on Si(001) substrates have shown that about 90% of the strain from lattice mismatch is dissipated in a few GaAs planes (∼10Ao) at the silicon interface. The other 10% of the strain is distributed uniformly throughout the bulk of the GaAs film. An exciting discovery of a huge x-ray magnetic resonance scattering effect in UAs that was larger than expected opens the door for mapping the magnetic structure of materials by tuning the x-ray energy near an absorption edge

  13. A plan of synchrotron light source dedicated to medical applications at NIRS

    International Nuclear Information System (INIS)

    A synchrotron light source dedicated to medical applications for practical use at a hospital is planned at NIRS. The system was designed for medical imaging with the synchrotron radiation (SR) for diagnosis of coronary arteries, coronary angiography, with monochromatic x-rays of 33 and 50 keV. The coronary angiography requires higher photon flux than the other applications, such as monochromatic x-ray computer tomography (CT). The conceptual design of the synchrotron light source is based on an electron storage ring with maximum energy of 2.3 GeV and beam current of 420 mA. Combination of the storage ring and a superconducting multipole wiggler is necessary to produce high photon flux required for the angiography. An electron linac of C-band has high electric field gradient. So it could be a good candidate of a injector for downsizing the whole system. Two beamlines of the insertion devices are planned to be used for clinical diagnoses, and other beam lines of bending magnets are prepared for basic experiments to support and develop the medical applications. (author)

  14. Synchrotron based mass spectrometry to investigate the molecular properties of mineral-organic associations

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Suet Yi; Kleber, Markus; Takahashi, Lynelle K.; Nico, Peter; Keiluweit, Marco; Ahmed, Musahid

    2013-04-01

    Soil organic matter (OM) is important because its decay drives life processes in the biosphere. Analysis of organic compounds in geological systems is difficult because of their intimate association with mineral surfaces. To date there is no procedure capable of quantitatively separating organic from mineral phases without creating artifacts or mass loss. Therefore, analytical techniques that can (a) generate information about both organic and mineral phases simultaneously and (b) allow the examination of predetermined high-interest regions of the sample as opposed to conventional bulk analytical techniques are valuable. Laser Desorption Synchrotron Postionization (synchrotron-LDPI) mass spectrometry is introduced as a novel analytical tool to characterize the molecular properties of organic compounds in mineral-organic samples from terrestrial systems, and it is demonstrated that when combined with Secondary Ion Mass Spectrometry (SIMS), can provide complementary information on mineral composition. Mass spectrometry along a decomposition gradient in density fractions, verifies the consistency of our results with bulk analytical techniques. We further demonstrate that by changing laser and photoionization energies, variations in molecular stability of organic compounds associated with mineral surfaces can be determined. The combination of synchrotron-LDPI and SIMS shows that the energetic conditions involved in desorption and ionization of organic matter may be a greater determinant of mass spectral signatures than the inherent molecular structure of the organic compounds investigated. The latter has implications for molecular models of natural organic matter that are based on mass spectrometric information.

  15. National Synchrotron Light Source 2010 Activity Report

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, M.; Snyder, K. J.

    2010-12-29

    This is a very exciting period for photon sciences at Brookhaven National Laboratory. It is also a time of unprecedented growth for the Photon Sciences Directorate, which operates the National Synchrotron Light Source (NSLS) and is constructing NSLS-II, both funded by the Department of Energy's Office of Science. Reflecting the quick pace of our activities, we chose the theme 'Discovery at Light Speed' for the directorate's 2010 annual report, a fiscal year bookended by October 2009 and September 2010. The year began with the news that NSLS users Venki Ramakrishnan of Cambridge University (also a former employee in Brookhaven's biology department) and Thomas A. Steitz of Yale University were sharing the 2009 Nobel Prize in Chemistry with Ada E. Yonath of the Weizmann Institute of Science. Every research project has the potential for accolades. In 2010, NSLS users and staff published close to 900 papers, with about 170 appearing in premiere journals. Those are impressive stats for a facility nearly three decades old, testament to the highly dedicated team keeping NSLS at peak performance and the high quality of its user community. Our NSLS users come from a worldwide community of scientists using photons, or light, to carry out research in energy and environmental sciences, physics, materials science, chemistry, biology and medicine. All are looking forward to the new capabilities enabled by NSLS-II, which will offer unprecedented resolution at the nanoscale. The new facility will produce x-rays more than 10,000 times brighter than the current NSLS and host a suite of sophisticated instruments for cutting-edge science. Some of the scientific discoveries we anticipate at NSLS-II will lead to major advances in alternative energy technologies, such as hydrogen and solar. These discoveries could pave the way to: (1) catalysts that split water with sunlight for hydrogen production; (2) materials that can reversibly store large quantities of

  16. Denaturing gradient gel electrophoresis

    International Nuclear Information System (INIS)

    It is worthwhile considering that only some 30 species make up the bulk of the bacterial population in human faeces at any one time based on the classical cultivation-based approach. The situation in the rumen is similar. Thus, it is practical to focus on specific groups of interest within the complex community. These may be the predominant or the most active species, specific physiological groups or readily identifiable (genetic) clusters of phylogenetically related organisms. Several 16S rDNA fingerprinting techniques can be invaluable for selecting and monitoring sequences or phylogenetic groups of interest and are described below. Over the past few decades, considerable attention was focussed on the identification of pure cultures of microbes on the basis of genetic polymorphisms of DNA encoding rRNA such as ribotyping, amplified fragment length polymorphism and randomly amplified polymorphic DNA. However, many of these methods require prior cultivation and are less suitable for use in analysis of complex mixed populations although important in describing cultivated microbial diversity in molecular terms. Much less attention was given to molecular characterization of complex communities. In particular, research into diversity and community structure over time has been revolutionized by the advent of molecular fingerprinting techniques for complex communities. Denaturing or temperature gradient gel electrophoresis (DGGE/TGGE) methods have been successfully applied to the analysis of human, pig, cattle, dog and rodent intestinal populations

  17. Injection system design for the LBL [Lawrence Berkeley Laboratory] 1-2 GeV synchrotron radiation source

    International Nuclear Information System (INIS)

    The injection system for the LBL 1 to 2 GeV Synchrotron Radiation Source is designed to provide an electron beam of 400 mA at 1.5 GeV to the storage ring in a filling time of less than 5 minutes. An alternate mode of operation requires that 7.6 mA be delivered to one, or a few rf bunches in the storage ring. To accomplish these tasks, a high intensity electron gun, a 50 MeV electron linac, and a 1.5 GeV booster synchrotron are used. The performance requirements of the injector complex are summarized. The electron gun and subharmonic buncher, linac design, and linac to booster and booster to storage ring transport are discussed as well as the booster synchrotron

  18. Synchrotron radiation. Basics, methods and applications

    Energy Technology Data Exchange (ETDEWEB)

    Mobilio, Settimio; Meneghini, Carlo [Roma Tre Univ. (Italy). Dept. of Science; Boscherini, Federico (ed.) [Bologna Univ. (Italy). Dept. of Physics and Astronomy

    2015-02-01

    Synchrotron radiation is today extensively used for fundamental and applied research in many different fields of science. Its exceptional characteristics in terms of intensity, brilliance, spectral range, time structure and now also coherence pushed many experimental techniques to previously un-reachable limits, enabling the performance of experiments unbelievable only few years ago. The book gives an up-to-date overview of synchrotron radiation research today with a view to the future, starting from its generation and sources, its interaction with matter, illustrating the main experimental technique employed and provides an overview of the main fields of research in which new and innovative results are obtained. The book is addressed to PhD students and young researchers to provide both an introductory and a rather deep knowledge of the field. It will also be helpful to experienced researcher who want to approach the field in a professional way.

  19. Indus synchrotron source: A national facility

    International Nuclear Information System (INIS)

    Indus Synchrotron Radiation complex at Raja Ramanna Centre for Advanced Technology at Indore, India houses two synchrotron radiation sources: Indus-1 and Indus-2 respectively. Indus-1 is a 450 MeV source emitting in VUV and soft x-ray region and operating at 100 mA since 1990 and Indus-2, designed for 2.5 GeV, 300 mA and is currently operating at 2 GeV and 100 mA. Indus-1 has five operational beamlines while Indus-2 has six beamlines installed and operational. Several materials research related problems have been investigated using the reflectivity and photo-electron spectroscopy beamlines at Indus-1 and also the beamlines at Indus-2. Here we will report the current status of both these sources and discuss a few of our studies carried out using these beamlines.

  20. Synchrotron Applications of High Magnetic Fields

    International Nuclear Information System (INIS)

    This workshop aims at discussing the scientific potential of X-ray diffraction and spectroscopy in magnetic fields above 30 T. Pulsed magnetic fields in the range of 30 to 40 T have recently become available at Spring-8 and the ESRF (European synchrotron radiation facility). This document gathers the transparencies of the 6 following presentations: 1) pulsed magnetic fields at ESRF: first results; 2) X-ray spectroscopy and diffraction experiments by using mini-coils: applications to valence state transition and frustrated magnet; 3) R5(SixGe1-x)4: an ideal system to be studied in X-ray under high magnetic field?; 4) high field studies at the Advanced Photon Source: present status and future plans; 5) synchrotron X-ray diffraction studies under extreme conditions; and 6) projects for pulsed and steady high magnetic fields at the ESRF

  1. Impact parameter profile of synchrotron radiation

    CERN Document Server

    Artru, X

    2005-01-01

    The horizontal impact parameter profile of synchrotron radiation, for fixed vertical angle of the photon, is calculated. This profile is observed through an astigmatic optical system, horizontally focused on the electron trajectory and vertically focused at infinity. It is the product of the usual angular distribution of synchrotron radiation, which depends on the vertical angle $\\psi$, and the profile function of a caustic staying at distance $\\bcl = (\\gamma^{-2} + \\psi^2) \\RB/2 $ from the orbit circle, $\\RB$ being the bending radius and $\\gamma$ the Lorentz factor. The {\\it classical impact parameter} $\\bcl$ is connected to the Schott term of radiation damping theory. The caustic profile function is an Airy function squared. Its fast oscillations allow a precise determination of the horizontal beam width.

  2. Phase contrast portal imaging using synchrotron radiation

    International Nuclear Information System (INIS)

    Microbeam radiation therapy is an experimental form of radiation treatment with great potential to improve the treatment of many types of cancer. We applied a synchrotron radiation phase contrast technique to portal imaging to improve targeting accuracy for microbeam radiation therapy in experiments using small animals. An X-ray imaging detector was installed 6.0 m downstream from an object to produce a high-contrast edge enhancement effect in propagation-based phase contrast imaging. Images of a mouse head sample were obtained using therapeutic white synchrotron radiation with a mean beam energy of 130 keV. Compared to conventional portal images, remarkably clear images of bones surrounding the cerebrum were acquired in an air environment for positioning brain lesions with respect to the skull structure without confusion with overlapping surface structures

  3. Synchrotron Mossbauer Spectroscopy of powder samples

    International Nuclear Information System (INIS)

    Synchrotron Mossbauer Spectroscopy, SMS, is an emerging technique that allows fast and accurate determination of hyperfine field parameters similar to conventional Mossbauer spectroscopy with radioactive sources. This new technique, however, is qualitatively different from Mossbauer spectroscopy in terms of equipment, methodology, and analysis to warrant a new name. In this paper, the authors report on isomer shift and quadrupole splitting measurements of Mohr's salt, Fe(NH4)2(SO4)2·6H2O for demonstration purposes. Theoretical calculations were performed and compared to experiments both in energy and time domain to demonstrate the influence of thickness distribution and preferential alignment of powder samples. Such measurements may prove to be useful when the data collection times are reduced to few seconds in the third generation, undulator based synchrotron radiation sources

  4. Diffusive synchrotron radiation from extragalactic jets

    CERN Document Server

    Fleishman, G D

    2006-01-01

    Flattenings of nonthermal radiation spectra observed from knots and interknot locations of the jets of 3C273 and M87 in UV and X-ray bands are discussed within modern models of magnetic field generation in the relativistic jets. Specifically, we explicitly take into account the effect of the small-scale random magnetic field, probably present in such jets, which gives rise to emission of Diffusive Synchrotron Radiation, whose spectrum deviates substantially from the standard synchrotron spectrum, especially at high frequencies. The calculated spectra agree well with the observed ones if the energy densities contained in small-scale and large-scale magnetic fields are comparable. The implications of this finding for magnetic field generation, particle acceleration, and jet composition are discussed.

  5. First dynamic computations of synchrotron emission from the cygnus a radio cavity: Evidence for electron pair plasma in cavity

    International Nuclear Information System (INIS)

    Cosmic rays, thermal gas and magnetic fields in FRII radio cavities are assumed to come entirely from winds flowing from just behind the jet shocks. Combining analytic and computational methods, it is shown that the computed radio-electron energy distribution and synchrotron emissivity spectra everywhere in the Cygnus A radio cavity agree with radio observations of the Cygnus A lobes. The magnetic field energy density is small everywhere and evolves passively in the post-shock wind. Most synchrotron emission arises in recent post-shock material as it flows back along the radio cavity wall. Because it experienced less adiabatic expansion, the magnetic field in this young backflow is larger than elsewhere in the radio lobe, explaining the observed radio synchrotron limb-brightening. The boundary backflow decelerates due to small cavity pressure gradients, causing large-scale fields perpendicular to the backflow (and synchrotron emission) to grow exponentially unlike observations. However, if the field is random on subgrid (sub-kpc) scales, the computed field reproduces both the magnitude and slowly decreasing radio synchrotron emissivity observed along the backflow. The radio synchrotron spectrum and image computed with a small-scale random field agree with Very Large Array observations. The total relativistic energy density in the post-jet shock region required in computations to inflate the radio cavity matches the energy density of relativistic electrons observed in the post-shock region of Cygnus A. This indicates that the component in the jet and cavity that dominates the dynamical evolution is a relativistic pair plasma.

  6. Ecdysis period of Rhodnius prolixus head investigated using phase contrast synchrotron microtomography.

    Science.gov (United States)

    Sena, G; Nogueira, L P; Braz, D; Almeida, A P; Gonzalez, M S; Azambuja, P; Colaço, M V; Barroso, R C

    2016-06-01

    Microtomography using synchrotron sources is a useful tool in biological imaging research since the phase coherence of synchrotron beams can be exploited to obtain images with high contrast resolution. This work is part of a series of works using phase contrast synchrotron microtomography in the study of Rhodnius prolixus head, the insect vector of Chagas' disease, responsible for about 12,000 deaths per year. The control of insect vector is the most efficient method to prevent this disease and studies have shown that the use of triflumuron, a chitin synthesis inhibitor, disrupted chitin synthesis during larval development and it's an alternative method against insect pests. The aim of this work was to investigate the biological effects of treatments with triflumuron in the ecdysis period (the moulting of the R. prolixus cuticle) using the new imaging beamline IMX at LNLS (Brazilian Synchrotron Light Laboratory). Nymphs of R. prolixus were taken from the Laboratory of Biochemistry and Physiology of Insects, Oswaldo Cruz Foundation, Brazil. Doses of 0.05mg of triflumuron were applied directly to the abdomen on half of the insects immediately after feeding. The insects were sacrificed 25days after feeding (intermoulting period) and fixed with glutaraldehyde. The results obtained using phase contrast synchrotron microtomography in R. prolixus showed amazing images of the effects of triflumuron on insects in the ecdysis period, and the formation of the new cuticle on those which were not treated with triflumuron. Both formation and malformation of this insect's cuticle have never been seen before with this technique. PMID:27184550

  7. Structural analysis with high brilliance synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Hideo [Japan Atomic Energy Research Inst., Kamigori, Hyogo (Japan). Kansai Research Establishment

    1997-11-01

    The research subjects in diffraction and scattering of materials with high brilliance synchrotron radiation such as SPring-8 (Super Photon ring 8 GeV) are summarized. The SPring-8 project is going well and 10 public beamlines will be opened for all users in October, 1997. Three JAERI beamlines are also under construction for researches of heavy element science, physical and structural properties under extreme conditions such as high temperature and high pressure. (author)

  8. Synchrotron radiation of a relativistic magneton

    Energy Technology Data Exchange (ETDEWEB)

    Bordovitsyn, V.A.; Torres, R.

    1986-11-01

    The classical theory of synchrotron radiation of an electrically neutral relativistic particle with a large intrinsic magnetic moment is considered (g-factor much greater than unit). The spectral-angular composition and polarization of the radiation are studied. The magneton radiation self-polarization time is calculated. It is shown that identical results follow from the Ternov-Bagrov-Khapaev quantum theory constructed on the basis of the Dirac-Pauli equation for a neutron.

  9. Diffraction measurements at sources of synchrotron radiation

    Czech Academy of Sciences Publication Activity Database

    Hašek, Jindřich

    Vol. 2a. Praha : Czech and Slovak Crystallographic Association, 2008, s. 15-16. ISSN 1211-5894. [Struktura 2008 - Colloquium of the Czech and Slovak Crystallographic Association. Valtice (CZ), 16.06.2008-20.06.2008] R&D Projects: GA AV ČR IAA500500701; GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : synchrotron radiation Subject RIV: CE - Biochemistry

  10. The Synchrotron Radiation for Steel Research

    OpenAIRE

    Piyada Suwanpinij

    2016-01-01

    The synchrotron X-ray radiation is a great tool in materials characterization with several advantageous features. The high intensity allows clear interaction signals and high energy of X-ray yields higher sampling volume. The samples do not need extra preparation and the microstructure is therefore not affected. With the tunability of the X-ray energy, a large range of elements and features in the samples can be investigated by different techniques, which is a significant difference between a...

  11. The Australian synchrotron - a progress report

    International Nuclear Information System (INIS)

    This paper summarises progress with the development of the Australian Synchrotron. The facility is based on the Boomerang Storage Ring which has a DBA structure with 14 superperiods. The design objective was to achieve a low emittance in a relatively compact circumference that had an excellent dynamic aperture and was obust with respect to potential construction aberrations. The potential suite of beamline and instrument stations is discussed and some examples are given

  12. Plasma diagnostics using synchrotron radiation in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Fidone, I.; Giruzzi, G.; Granata, G.

    1995-09-01

    This report deal with the use of synchrotron radiation in tokamaks. The main advantage of this new method is that it enables to overcome several deficiencies, caused by cut-off, refraction, and harmonic overlap. It also makes it possible to enhance the informative contents of the familiar low harmonic scheme. The basic theory of the method is presented and illustrated by numerical applications, for plasma parameters of relevance in present and next step tokamaks. (TEC). 10 refs., 13 figs.

  13. Paraxial Green's functions in synchrotron radiation theory

    International Nuclear Information System (INIS)

    This work contains a systematic treatment of single particle synchrotron radiation and some application to realistic beams with given cross section area, divergence and energy spread. Standard theory relies on several approximations whose applicability limits and accuracy are often forgotten. We begin remarking that on the one hand, a paraxial approximation can always be applied without loss of generality and with ultra relativistic accuracy. On the other hand, dominance of the acceleration field over the velocity part in the Lienard-Wiechert expressions is not always guaranteed and constitutes a separate assumption, whose applicability is discussed. Treating synchrotron radiation in paraxial approximation we derive the equation for the slow varying envelope function of the Fourier components of the electric field vector. Calculations of Synchrotron Radiation properties performed by others showed that the phase of the Fourier components of the electric field vector differs from the phase of a virtual point source. In this paper we present a systematic, analytical description of this phase shift, calculating amplitude and phase of electric field from bending magnets, short magnets, two bending magnet system separated by a straight section (edge radiation) and undulator devices. We pay particular attention to region of applicability and accuracy of approximations used. Finally, taking advantage of results of analytical calculation presented in reduced form we analyze various features of radiation from a complex insertion device (set of two undulators with a focusing triplet in between) accounting for the influence of energy spread and electron beam emittance. (orig.)

  14. Synchrotron-radiation experiments with recoil ions

    Energy Technology Data Exchange (ETDEWEB)

    Levin, J.C.

    1989-01-01

    Studies of atoms, ions and molecules with synchrotron radiation have generally focused on measurements of properties of the electrons ejected during, or after, the photoionization process. Much can also be learned, however, about the atomic or molecular relaxation process by studies of the residual ions or molecular fragments following inner-shell photoionization. Measurements are reported of mean kinetic energies of highly charged argon, krypton, and xenon recoil ions produced by vacancy cascades following inner-shell photoionization using white and monochromatic synchrotron x radiation. Energies are much lower than for the same charge-state ions produced by charged-particle impact. The results may be applicable to design of future angle-resolved ion-atom collision experiments. Photoion charge distributions are presented and compared with other measurements and calculations. Related experiments with synchrotron-radiation produced recoil ion, including photoionization of stored ions and measurement of shakeoff in near-threshold excitation, are briefly discussed. 24 refs., 6 figs., 1 tab.

  15. MICROANALYSIS OF MATERIALS USING SYNCHROTRON RADIATION.

    Energy Technology Data Exchange (ETDEWEB)

    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 possible 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.

  16. Tabletop synchrotron and its unique features

    CERN Document Server

    Yamada, H

    2002-01-01

    Two synchrotrons, AURORA and MIRRORCLE, were built in Ritsumeikan University. MIRRORCLE-20 is the smallest normal conduction synchrotron (15 cm orbit radius and 1.2 m outer diameter) in the world. It uses 2/3 resonance method for electron beam incidence but is not optimized for X-ray generation. MIRRORCLE-6 shall be optimized for X-ray generation. X-ray generated by MIRRORCLE shows very flat white light, rich in hard X-ray, pulse with width changeable from a few mu s to a few ms , wide radiation angle of 25 mrad at MIRRORCLE-20 and 80 mrad at MIRRORCLE-8 and high coherence. The feature such as pulsed light and high coherence is expected to new application which photon radiation cannot practice. Imaging experiments by MIRRORCLE were carried out by Cu plate, Al plate, Teflon and acryl plate. We took a photograph of insect, electric lamp, connector, and cyclotron. New X-ray generation mechanism, X-ray strength, development of tabletop synchrotron and features of X-ray beam are explained. (S.Y.)

  17. Electric field gradients in metals

    International Nuclear Information System (INIS)

    A review of the recent works on electric field gradient in metals is given. The main emphasis is put on the temperature dependence of the electric field gradient in nonmagnetic metals. Some methods of investigation of this effect using nuclear probes are described. One of them is nuclear accoustic resonance method. (S.B.)

  18. Computational Strain Gradient Crystal Plasticity

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Kysar, Jeffrey W.

    2011-01-01

    A model for strain gradient crystal visco-plasticity is formulated along the lines proposed by Fleck andWillis (2009) for isotropic plasticity. Size-effects are included in the model due to the addition of gradient terms in both the free energy as well as through a dissipation potential. A finite...

  19. Adiabatic calorimeter for measuring absorbed dose of IHEP synchrotron secondary radiation

    International Nuclear Information System (INIS)

    An adiabatic calorimeter for measuring the value of absorbed dose of mixed radiation generated by 70 GeV proton synchrotron is described. The calorimetric system consists of a working body (a core) and a shell (a screen). The calorimeter adiabaticity is provided by the absence of the core-shell heat exchange by maintaining the shell temperature equal to the core temperature and, consequently, the whole energy generated in the core goes for its heating. The work showed the possibility of carrying out the adiabatic calorimetric measurements of absorbed dose of secondary radiation generated by un accelerated proton beam under the conditions of alternating magnetic and electric fields at the IHEP proton synchrotron at the average dose rate not less than 5x10-3 Wxkg-1

  20. Study on alumina-alumina brazing for application in vacuum chambers of proton synchrotron

    International Nuclear Information System (INIS)

    The paper describes an experimental study to standardize vacuum brazing process to obtain satisfactory high purity alumina brazed joints for application in rapid cycle proton synchrotron machine. Two different brazing routes, adopted for making alumina-alumina brazed joints, included (i) multi-step Mo-Mn metallization and brazing with BVAg-8 alloy and (ii) advanced single-step active brazing with CuSil-ABA alloy. Brazed alumina specimens, prepared by both the routes, yielded ultra high vacuum compatible, helium leak tight and bakeable joints. Active-brazed specimens exhibited satisfactory strength values in tensile and four-point bend tests. Metallized-brazed specimens, although exhibited relatively lower tensile strength than the targeted value, displayed satisfactory flexural strength in four-point bend test. The results of the study demonstrated that active brazing is the simple and cost effective alternative to conventional metallization route for producing satisfactory brazed joints for application in rapid cycle proton synchrotron machine. (author)

  1. Operating synchrotron light sources with a high gain free electron laser

    Science.gov (United States)

    Di Mitri, S.; Cornacchia, M.

    2015-11-01

    Since the 1980s synchrotron light sources have been considered as drivers of a high repetition rate (RR), high gain free electron laser (FEL) inserted in a by-pass line or in the ring itself. As of today, the high peak current required by the laser is not deemed to be compatible with the standard multi-bunch filling pattern of synchrotrons, and in particular with the operation of insertion device (ID) beamlines. We show that this problem can be overcome by virtue of magnetic bunch length compression in a ring section, and that, after lasing, the beam returns to equilibrium conditions without beam quality disruption. Bunch length compression brings a double advantage: the high peak current stimulates a high gain FEL emission, while the large energy spread makes the beam less sensitive to the FEL heating and to the microwave instability in the ring. The beam’s large energy spread at the undulator is matched to the FEL energy bandwidth through a transverse gradient undulator. Feasibility of lasing at 25 nm is shown for the Elettra synchrotron light source at 1 GeV, and scaling to shorter wavelengths as a function of momentum compaction, beam energy and transverse emittance in higher energy, larger rings is discussed. For the Elettra case study, a low (100 Hz) and a high (463 kHz) FEL RR are considered, corresponding to an average FEL output power at the level of ∼1 W (∼1013 photons per pulse) and ∼300 W (∼1011 photons per pulse), respectively. We also find that, as a by-product of compression, the ∼5 W Renieri’s limit on the average FEL power can be overcome. Our conclusion is that existing and planned synchrotron light sources may be made compatible with this new hybrid IDs-plus-FEL operational mode, with little impact on the standard beamlines functionality.

  2. Development of nano structured diamond windows for application in synchrotron beamlines

    International Nuclear Information System (INIS)

    Full text. Synchrotron light sources are important tools in the scientific field. In essence, they are rather like enormous super-microscopes capable of studying biological, chemical and material samples at very high resolution, down to the atomic and molecular level, by using synchrotron light. The intense synchrotron light is electromagnetic radiation produced by high-energy electrons in a particle accelerator. The configuration of the beamlines uses windows of material transparent to radiation. Beryllium (Be) is the standard material. In general, these windows serve both, as filters to absorb the photons of low energy and, as insulating barrier between the storage ring and the environment. The justification for the use of beryllium windows at synchrotron beamlines is that elements with low atomic number - (4) transmit more electromagnetic radiation. Besides all the qualities, beryllium has some drawbacks such as deterioration of spatial coherence due to surface roughness and defects. Another problem observed is the appearance of Fresnel diffraction due to manufacturing defects of the windows. In this paper, we propose the use of windows made of nano structured diamond with average roughness of 20nm, without the need to polish, with maximum thickness of around 3 μm. Diamond also has a low atomic number - (6). Another quality of nano structured diamond films is its mechanical properties. It needs only 5-6% of the thickness of beryllium to withstand the same pressure gradient. The film morphology was characterized with the help of Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM-FEG). Diamond's quality was determined by Raman Spectroscopy

  3. Cosmic alternatives?

    Science.gov (United States)

    Gregory, Ruth

    2009-04-01

    "Cosmologists are often in error but never in doubt." This pithy characterization by the Soviet physicist Lev Landau sums up the raison d'être of Facts and Speculations in Cosmology. Authors Jayant Narlikar and Geoffrey Burbidge are proponents of a "steady state" theory of cosmology, and they argue that the cosmological community has become fixated on a "Big Bang" dogma, suppressing alternative viewpoints. This book very much does what it says on the tin: it sets out what is known in cosmology, and puts forward the authors' point of view on an alternative to the Big Bang.

  4. Alternating current electroluminescent properties of zinc sulfide powders

    OpenAIRE

    Salimian, Alireza

    2012-01-01

    In order to investigate the alternating current electroluminescent properties of zinc sulfide powders the following experiments were conducted: synthesis of zinc sulfide phosphors (comprised of zinc, sulfur and copper dopant); thermal shocking of phosphor materials (sudden cooling, using liquid nitrogen, of phosphor particles heated up to 500oC) and analysis of their alternating current electroluminescent properties as well as studies of particle crystal structures by synchrotron and conventi...

  5. Growing Alternatives

    DEFF Research Database (Denmark)

    Bagger-Petersen, Mai Corlin

    2014-01-01

    From 2014, Anhui Province will pilot a reform of the residential land market in China, thus integrating rural Anhui in the national housing market. In contrast, artist and activist Ou Ning has proposed the Bishan time money currency, intending to establish an alternative economic circuit in Bishan...

  6. New synchrotron radiation facility project. Panel on new synchrotron radiation facility project

    CERN Document Server

    Sato, S; Kimura, Y

    2003-01-01

    The project for constructing a new synchrotron radiation facility dedicated to the science in VUV (or EUV) and Soft X-ray (SX) region has been discussed for these two years at the Panel on New Synchrotron Radiation Facility Project. The Panel together with the Accelerator Design Working Group (WG), Beamline Design WG and Research Program WG suggested to the Ministry of Education, Science, Culture and Sports the construction of a 1.8 GeV electron storage ring suitable for 'Top-Up' operation and beamlines and monochromators designed for undulator radiation. The scientific programs proposed by nationwide scientists are summarized with their requirements of the characteristics of the beam. (author)

  7. Medical applications of synchrotron radiation at the National Synchrotron Light Source

    International Nuclear Information System (INIS)

    The overriding features of the synchrotron beams which make them applicable to medical research are their extremely high intensity and broadband energy spectrum. Several orders of magnitude separate the smooth, continuous spectrum of the synchrotron from the sharply peaked characteristic emission spectrum of a conventional source. Basically, the high intensity and tunability allow monochromatic beams to be generated at virtually any energy. The standard problem of beam hardening in both medical imaging and therapy is eliminated by the monochromatic beams since the energy spectrum does not change with passage through tissue. The tunable spectrum allows enhancement of images and therapeutic dose by selection of the most effective energy for a given procedure

  8. Combining Step Gradients and Linear Gradients in Density.

    Science.gov (United States)

    Kumar, Ashok A; Walz, Jenna A; Gonidec, Mathieu; Mace, Charles R; Whitesides, George M

    2015-06-16

    Combining aqueous multiphase systems (AMPS) and magnetic levitation (MagLev) provides a method to produce hybrid gradients in apparent density. AMPS—solutions of different polymers, salts, or surfactants that spontaneously separate into immiscible but predominantly aqueous phases—offer thermodynamically stable steps in density that can be tuned by the concentration of solutes. MagLev—the levitation of diamagnetic objects in a paramagnetic fluid within a magnetic field gradient—can be arranged to provide a near-linear gradient in effective density where the height of a levitating object above the surface of the magnet corresponds to its density; the strength of the gradient in effective density can be tuned by the choice of paramagnetic salt and its concentrations and by the strength and gradient in the magnetic field. Including paramagnetic salts (e.g., MnSO4 or MnCl2) in AMPS, and placing them in a magnetic field gradient, enables their use as media for MagLev. The potential to create large steps in density with AMPS allows separations of objects across a range of densities. The gradients produced by MagLev provide resolution over a continuous range of densities. By combining these approaches, mixtures of objects with large differences in density can be separated and analyzed simultaneously. Using MagLev to add an effective gradient in density also enables tuning the range of densities captured at an interface of an AMPS by simply changing the position of the container in the magnetic field. Further, by creating AMPS in which phases have different concentrations of paramagnetic ions, the phases can provide different resolutions in density. These results suggest that combining steps in density with gradients in density can enable new classes of separations based on density. PMID:25978093

  9. The 10 to 20 GeV Cornell Electron Synchrotron

    CERN Document Server

    Wilson, Richard R

    1967-01-01

    The National Science Foundation awarded a contract to Cornell University on April 4, 1965 for the construction of a 10 Gev electron synchrotron. The synchrotron itself has now been built and preliminary tests have been made at low energy. The present report is largely a revision and up-dating of CS DC-26 which was written two years ago when the construction of the synchrotron was authorized.

  10. Atomic photoelectron-spectroscopy studies using synchrotron radiation

    International Nuclear Information System (INIS)

    Photoelectron spectroscopy combined with tunable synchrotron radiation has been used to study the photoionization process in several atomic systems. The time structure of the synchrotron radiation source at the Stanford Synchrotron Radiation Laboratory (SSRL) was used to record time-of-flight (TOF) photoelectron spectra of gaseous Cd, Hg, Ne, Ar, Ba, and Mn. The use of two TOF analyzers made possible the measurement of photoelectron angular distributions as well as branching ratios and partial cross sections

  11. Atomic photoelectron-spectroscopy studies using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kobrin, P.H.

    1983-02-01

    Photoelectron spectroscopy combined with tunable synchrotron radiation has been used to study the photoionization process in several atomic systems. The time structure of the synchrotron radiation source at the Stanford Synchrotron Radiation Laboratory (SSRL) was used to record time-of-flight (TOF) photoelectron spectra of gaseous Cd, Hg, Ne, Ar, Ba, and Mn. The use of two TOF analyzers made possible the measurement of photoelectron angular distributions as well as branching ratios and partial cross sections.

  12. Injection System design for a hadron therapy Synchrotron

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jin-Quan; SONG Ming-Tao; WEI Bao-Wen

    2008-01-01

    A synchrotron is designed for tumour therapy with C6+ ions or proton.Its injector is a cyclotron, which delivers C5+or H+2 ions to the synchrotron.After comparing the methods of the single-turn injection, the multi-turn injection and the stripping injection,this paper chooses the stripping injection method.In addition,the concept design of the injection system is presented,in which the synchrotron lattice is optimized.

  13. The Synchrotron Boiler: a Thermalizer in Seyfert Galaxies

    OpenAIRE

    Ghisellini, Gabriele; Haardt, Francesco; Svensson, Roland

    1996-01-01

    There are difficulties in understanding what keeps the plasma thermalized in compact sources, especially during rapid variations of the emitted flux. Particle-particle collisions are too inefficient in hot rarefied plasmas, and a faster process is called for. Synchrotron absorption is such a process. We show that relativistic electrons can thermalize in a few synchrotron cooling times by emitting and absorbing cyclo-synchrotron photons. The resulting equilibrium distribution is a Maxwellian a...

  14. Impact of synchrotron radiation on macromolecular crystallography: a personal view

    International Nuclear Information System (INIS)

    This article, largely based on personal experiences of the authors, reviews the early history of the application of synchrotron radiation to structural biology, and particularly protein crystallography, to show the tremendous impact that this experimental innovation has had on these disciplines. 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

  15. Synchrotron radiation direct photoetching of polymers and crystals for micromachining

    International Nuclear Information System (INIS)

    Synchrotron radiation etching of polymers and optical crystals which are transparent throughout the spectral range from visible to ultraviolet has been carried out without using any chemicals, successfully creating high-aspect-ratio microstructures for micromachining. A detailed study of the etching rates by varying the synchrotron beam current, sample temperature, beam size and aspect ratio showed that this synchrotron radiation process is essentially different from laser ablation, while an in situ mass spectrometric analysis of gaseous etching products showed that the dissociation mechanism involved with the synchrotron radiation processing, even with heating, is completely different from the thermal dissociation of the laser ablation

  16. Alternative 23

    OpenAIRE

    Jackson, Mark

    2014-01-01

    Alternative 23 is a curated exhibition of works by Steve Aylett, David Blandy & Daniel Locke, Let Me Feel Your Finger First, Laura Oldfield Ford, Plastique Fantastique and Henrik Schrat, including the first screening of Let Me Feel Your Finger First’s Postcolonial Capers. In 1985 DC Comics in the US had taken the commercial decision to unify the complex and contradictory character story arcs from its various strips such as Superman, Batman and Green Lantern. The resultant crossover series...

  17. Spatial gradient tuning in metamaterials

    Science.gov (United States)

    Driscoll, Tom; Goldflam, Michael; Jokerst, Nan; Basov, Dimitri; Smith, David

    2011-03-01

    Gradient Index (GRIN) metamaterials have been used to create devices inspired by, but often surpassing the potential of, conventional GRIN optics. The unit-cell nature of metamaterials presents the opportunity to exert much greater control over spatial gradients than is possible in natural materials. This is true not only during the design phase but also offers the potential for real-time reconfiguration of the metamaterial gradient. This ability fits nicely into the picture of transformation-optics, in which spatial gradients can enable an impressive suite of innovative devices. We discuss methods to exert control over metamaterial response, focusing on our recent demonstrations using Vanadium Dioxide. We give special attention to role of memristance and mem-capacitance observed in Vanadium Dioxide, which simplify the demands of stimuli and addressing, as well as intersecting metamaterials with the field of memory-materials.

  18. Flame Propagation Through Concentration Gradient

    Institute of Scientific and Technical Information of China (English)

    JunyaIINO; MitsuakiTANABE; 等

    2000-01-01

    The experiment was carried out in homogeneous propane-air mixture and in several concentration gradient of mixture.Igniter is put on the upper side of the combustion chamber,In concentration gradient experiment.ixture was ignited from lean side.An experimental study was conducted in a combustion chamber.The combustion chamber has glass windows for optical measurements at any side.For the measurement of distribution of fuel concentration,infraed absorption method using 3.39μm He-Ne laser was used,and for the observation of proagating flams,Schlieren method was employed.As a measurment result of flame propagation velocity and flammable limit,for a mixture of an identical local equivalence ratio.flame propagation velocity in concentration gradient is faster than that in homogeneous mixture,and rich flammable limit in concentration gradient shows a tendency to be higher than that in homogeneous mixture.

  19. Sobolev gradients and differential equations

    CERN Document Server

    Neuberger, John William

    1997-01-01

    A Sobolev gradient of a real-valued functional is a gradient of that functional taken relative to the underlying Sobolev norm. This book shows how descent methods using such gradients allow a unified treatment of a wide variety of problems in differential equations. Equal emphasis is placed on numerical and theoretical matters. Several concrete applications are made to illustrate the method. These applications include (1) Ginzburg-Landau functionals of superconductivity, (2) problems of transonic flow in which type depends locally on nonlinearities, and (3) minimal surface problems. Sobolev gradient constructions rely on a study of orthogonal projections onto graphs of closed densely defined linear transformations from one Hilbert space to another. These developments use work of Weyl, von Neumann and Beurling.

  20. Application of synchrotron radiation in material Science

    International Nuclear Information System (INIS)

    In recent years many synchrotron radiation facilities are built around the world. The properties of this radiation, it's intensity and tuneability, are leading to exciting new experiments in chemistry, physics, biology and material sciences. In X-ray crystallographic studies, data can be collected on very small samples of only a few microns in size and time as short as one millisecond. Other techniques allow us to probe the local structures of impurities in technologically important materials. In the present paper unique properties of synchrotron radiation will be described. X-ray diffraction (XRD) and X-ray Absorption Fine Structure (XAFS) spectroscopic techniques are now routinely used for materials characterization. X-ray Absorption Fine Structure (XAFS) spectroscopic techniques have been applied to study the local structural environment of host and dopant cations in complex systems. X-ray Absorption Near Edge Structure (XANES) spectroscopy is useful to determine the valence state of different cations. To examine the local structure around different cations Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy is the most appropriate technique. A review of these methodologies and the results on Yba/sub 2/ Cu/sub 3-x/ Sb/sub x/O/sub 7/, and SrFe/sub 1-x/ Nb/sub x/O/sub 3/ (where x = 0.0 and 0.5) will be presented. The Synchrotron light for Experimental Science and Applications in the Middle East (SESAME) is under construction in jordan, Pakistan in one of the member states of SESAME project, therefore a brief review of SESAME will be presented. (author)

  1. Laser synchrotron radiation and beam cooling

    Energy Technology Data Exchange (ETDEWEB)

    Esarey, E.; Sprangle, P.; Ting, A. [Naval Research Lab., Washington, DC (United States)] [and others

    1995-12-31

    The interaction of intense {approx_gt} 10{sup 18} W/cm{sup 2}, short pulse ({approx_lt} 1 ps) lasers with electron beams and plasmas can lead to the generation of harmonic radiation by several mechanisms. Laser synchrotron radiation may provide a practical method for generating tunable, near monochromatic, well collimated, short pulse x-rays in compact, relatively inexpensive source. The mechanism for the generation of laser synchrotron radiation is nonlinear Thomson scattering. Short wavelengths can be generated via Thomson scattering by two methods, (i) backscattering from relativistic electron beams, in which the radiation frequency is upshifted by the relativistic factor 4{gamma}{sup 2}, and (ii) harmonic scattering, in which a multitude of harmonics are generated with harmonic numbers extending out to the critical harmonic number nc{approx_equal}a{sub 0}{sup 3} {much_gt} 1, where a{sub 0} {approx_equal}10{sup -9}{lambda}I{sup 1/2}, {lambda} is the laser wavelength in {mu}m and I is the laser intensity in W/cm{sup 2}. Laser synchrotron sources are capable of generating short ({approx_lt} ps) x-ray pulses with high peak flux ({approx_gt} 10{sup 21} photons/s) and brightness ({approx_gt}{sup 19} photons/s-mm{sup 2}-mrad{sup 2} 0.1%BW. As the electron beam radiates via Thomson scattering, it can subsequently be cooled, i.e., the beam emittance and energy spread can be reduced. This cooling can occur on rapid ({approximately} ps) time scales. In addition, electron distributions with sufficiently small axial energy spreads can be used to generate coherent XUV radiation via a laser-pumped FEL mechanism.

  2. Synchrotron radiation facilities in the USA

    International Nuclear Information System (INIS)

    With the successful commissioning and achievement of significant milestones at both the 7-GeV Advanced Photon Source (APS) and the 1.5- GeV Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory, synchrotron radiation research capability in the United States holds the promise of many important discoveries in the decade to come. An overview of current accelerator commissioning performance at the American third-generation light sources, state-of-the-art developments at first- and second-generation sources, and a preview of fourth-generation source progress is presented

  3. X-ray microscopy using synchrotron radiation

    International Nuclear Information System (INIS)

    The system for x-ray microscopy now being developed at the X-26 beam line of the Brookhaven National Synchrotron Light Source (NSLS) is described here. Examples of the use of x-ray microscopy for trace element geochemistry, biology and medicine, and materials investigations are given to emphasize the scientific applications of the technique. Future directions for the improvement and further development of the X-26 microscope and of the x-ray microscopy field in general are discussed. 11 refs., 7 figs

  4. Glancing angle synchrotron X-ray diffraction

    International Nuclear Information System (INIS)

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

  5. Spherical quartz crystals investigated with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, N. R. [Ecopulse, Inc., 7844 Vervain Ct., Springfield, Virginia 22152 (United States); Macrander, A. T. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Hill, K. W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08536 (United States); Baronova, E. O. [Kurchatov Institute, Moscow (Russian Federation); George, K. M.; Kotick, J. [The Ohio State University, Columbus, Ohio 43210 (United States)

    2015-10-15

    The quality of x-ray spectra and images obtained from plasmas with spherically bent crystals depends in part on the crystal’s x-ray diffraction across the entire crystal surface. We employ the energy selectivity and high intensity of synchrotron radiation to examine typical spherical crystals from alpha-quartz for their diffraction quality, in a perpendicular geometry that is particularly convenient to examine sagittal focusing. The crystal’s local diffraction is not ideal: the most noticeable problems come from isolated regions that so far have failed to correlate with visible imperfections. Excluding diffraction from such problem spots has little effect on the focus beyond a decrease in background.

  6. Spherical quartz crystals investigated with synchrotron radiation

    International Nuclear Information System (INIS)

    The quality of x-ray spectra and images obtained from plasmas with spherically bent crystals depends in part on the crystal’s x-ray diffraction across the entire crystal surface. We employ the energy selectivity and high intensity of synchrotron radiation to examine typical spherical crystals from alpha-quartz for their diffraction quality, in a perpendicular geometry that is particularly convenient to examine sagittal focusing. The crystal’s local diffraction is not ideal: the most noticeable problems come from isolated regions that so far have failed to correlate with visible imperfections. Excluding diffraction from such problem spots has little effect on the focus beyond a decrease in background

  7. Spherical quartz crystals investigated with synchrotron radiation

    Science.gov (United States)

    Pereira, N. R.; Macrander, A. T.; Hill, K. W.; Baronova, E. O.; George, K. M.; Kotick, J.

    2015-10-01

    The quality of x-ray spectra and images obtained from plasmas with spherically bent crystals depends in part on the crystal's x-ray diffraction across the entire crystal surface. We employ the energy selectivity and high intensity of synchrotron radiation to examine typical spherical crystals from alpha-quartz for their diffraction quality, in a perpendicular geometry that is particularly convenient to examine sagittal focusing. The crystal's local diffraction is not ideal: the most noticeable problems come from isolated regions that so far have failed to correlate with visible imperfections. Excluding diffraction from such problem spots has little effect on the focus beyond a decrease in background.

  8. Emittance growth from transient coherent synchrotron radiation

    International Nuclear Information System (INIS)

    If the energies of individual particles in a bunch change as the bunch traverses a bending system, even if it is achromatic, betatron oscillations can be excited. Consequently, the transverse emittance of the bunch will grow as it moves downstream. Short bunches may be particularly susceptible to emission of coherent synchrotron radiation which can act back on the particles to change their energies and trajectories. Because a bend spans a well-defined length and angle, the bunch-excited wakefield and its effect back on the bunch are inherently transient. We outline a recently developed theory of this effect and apply it to example bending systems

  9. Matching to gantries for medical synchrotrons

    CERN Document Server

    Benedikt, Michael

    1997-01-01

    Treatment of tumours by hadron-therapy is greatly improved if the patient can be irradiated from different directions. This task is performed by a gantry, i.e. a section of beam line that can be rotated around the patient. The gantry optics have to be designed in such a way that the beam at the patient is independent of the rotation angle. The various matching techniques are briefly reviewed in the light of the current development in medical synchrotrons towards active scanning, which requires a small, high-precision beam spot at the patient. In particular, beam delivery systems with rotators are discussed.

  10. CRYRING - a synchrotron, cooler and storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamsson, K.; Andler, G.; Bagge, L.; Beebe, E.; Carle, P.; Danared, H.; Egnell, S.; Ehrnsten, K.; Engstroem, M.; Herrlander, C.J.; Hilke, J.; Jeansson, J.; Kaellberg, A.; Leontein, S.; Liljeby, L.; Nilsson, A.; Paal, A.; Rensfelt, K.G.; Rosengaard, U.; Simonsson, A.; Soltan, A.; Starker, J.; Ugglas, M. (Manne Siegbahn Inst. of Physics, Stockholm (Sweden)) Filevich, A. (CNEA, Physics Dept., Tandar, Buenos Aires (Argentina))

    1993-06-01

    CRYRING is a small synchrotron and storage ring equipped with electron cooling. Highly charged ions from the electron beam ion source CRYSIS or singly charged ions from the plasmatron source MINIS are injected via an RFQ into the ring. The facility is in the commissioning phase. Full design energy has been achieved and electron cooling demonstrated both for atomic and molecular ions. The experimental program started in August with two projects, dissociative recombination of H[sup +][sub 3] ions and radiative recombination to deuterons. The status as of September 20, 1992, is reported. (orig.)

  11. Bent approximations to synchrotron radiation optics

    International Nuclear Information System (INIS)

    Ideal optical elements can be approximated by bending flats or cylinders. This paper considers the applications of these approximate optics to synchrotron radiation. Analytic and raytracing studies are used to compare their optical performance with the corresponding ideal elements. It is found that for many applications the performance is adequate, with the additional advantages of lower cost and greater flexibility. Particular emphasis is placed on obtaining the practical limitations on the use of the approximate elements in typical beamline configurations. Also considered are the possibilities for approximating very long length mirrors using segmented mirrors

  12. Biological effects of synchrotron radiation on crops

    Institute of Scientific and Technical Information of China (English)

    唐掌雄; 董保中; 等

    1996-01-01

    The sensitivity of germinating seeds of barley,winter wheat and spring one to synchrotron ultraviolet radiation is barley>winter wheat and spring one.But when dry seeds of the three crops are irradiated by 3.5-22keV X-rays,the sequence of their sensitivity to radiation can be changed.for irradiation of 0.6-3keV ultra soft X-rays,0.40-0.90 of the seedlings of the first generation appear mutation of striped chlorophyll defect.This biological effect has never been found for irradiation of other rays.

  13. Tolerances in diffraction limited synchrotron light sources

    International Nuclear Information System (INIS)

    The PEP storage ring at Stanford can be operated to become a synchrotron light source of super-high brightness. Using a combination of a high-tune configuration and damping wigglers, the beam emittance can be reduced to less than 6 A rad at 6 GeV. For such small beam emittance, alignment and field tolerances as well as nonlinear fields in the wiggler magnets can significantly perturb the attainable low-emittance. This paper reports on studies to control and establish the tolerances required for the operation of a super-low-emittance storage ring. (orig.)

  14. Precision geometric parameter gage for synchrotron radiation

    CERN Document Server

    Gubrienko, K I; Makonin, S; Seleznev, V; Solodovnik, F; Sytin, A N; Vrazhnov, M; Wittenburg, K

    2001-01-01

    This article includes the description of the geometric parameter gage device prototype for synchrotron radiation of HERA collider (DESY). The system construction which capable to measure photo current, caused by such a radiation in a refractory metal, described here. The system component parts are: measuring heads and photo current measuring electronics designed by IHEP, stepper motor by Vacuum Generators with HEDS-550X encoder by Hewlett Packard, PCI-STEP-4CX 4-Axis Closed Loop Step controller by National Instruments. The device is controlled by means of Microsoft Visual Basic program using Value Motion Windows Libraries. The device prototype was tested in the beam of the DORIS storage ring.

  15. Synchrotron radiation facilities in the USA

    Energy Technology Data Exchange (ETDEWEB)

    Decker, G.

    1996-07-01

    With the successful commissioning and achievement of significant milestones at both the 7-GeV Advanced Photon Source (APS) and the 1.5- GeV Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory, synchrotron radiation research capability in the United States holds the promise of many important discoveries in the decade to come. An overview of current accelerator commissioning performance at the American third-generation light sources, state-of-the-art developments at first- and second-generation sources, and a preview of fourth-generation source progress is presented.

  16. 3D IMAGING USING COHERENT SYNCHROTRON RADIATION

    Directory of Open Access Journals (Sweden)

    Peter Cloetens

    2011-05-01

    Full Text Available Three dimensional imaging is becoming a standard tool for medical, scientific and industrial applications. The use of modem synchrotron radiation sources for monochromatic beam micro-tomography provides several new features. Along with enhanced signal-to-noise ratio and improved spatial resolution, these include the possibility of quantitative measurements, the easy incorporation of special sample environment devices for in-situ experiments, and a simple implementation of phase imaging. These 3D approaches overcome some of the limitations of 2D measurements. They require new tools for image analysis.

  17. Medical applications of synchrotron radiation. Ch. 10

    International Nuclear Information System (INIS)

    Synchrotron radiation has a number of properties which make it uniquely suited for medical diagnostic imaging. The radiation is intense and can be readily monochromatized. With these highly intense, mono-chromatized X-ray beams, iodine K-edge di-chromatography can yield images which greatly enhance the visualization of iodine containing structures. As this technology continues to improve, the possibility of performing diagnostic cardiac, neuroradiological, and other vascular examinations with minimally invasive peripheral venous injections of iodinated contrast agent becomes increasingly practical. (author). 10 refs.; 6 figs

  18. Glancing angle synchrotron X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-09-01

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

  19. Effective spectrum width of the synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bagrov, V. G., E-mail: bagrov@phys.tsu.ru [Department of Physics, Tomsk State University, Tomsk (Russian Federation); Institute of High Current Electronics, SB RAS, Tomsk (Russian Federation); Gitman, D. M., E-mail: gitman@if.usp.br [Department of Physics, Tomsk State University, Tomsk (Russian Federation); Institute of Physics, University of São Paulo, São Paulo (Brazil); P.N.Lebedev Physical Institute, Moscow (Russian Federation); Levin, A. D., E-mail: alevin@if.usp.br [Institute of Physics, University of São Paulo, São Paulo (Brazil); Loginov, A. S.; Saprykin, A. D. [Department of Physics, Tomsk State University, Tomsk (Russian Federation)

    2015-11-25

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory.

  20. Gradient boosting machines, a tutorial

    OpenAIRE

    Natekin, Alexey; Knoll, Alois

    2013-01-01

    Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods with a strong focus on machine learning aspects of modeling. A theoretical information is complemented with de...

  1. Gradient Boosting Machines, A Tutorial

    OpenAIRE

    Alexey Natekin; Alois Knoll

    2013-01-01

    Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all th...

  2. Synchrotron Lightcurves of blazars in a time-dependent synchrotron-self Compton cooling scenario

    CERN Document Server

    Zacharias, Michael

    2013-01-01

    Blazars emit non-thermal radiation in all frequency bands from radio to \\gamma-rays. Additionally, they often exhibit rapid flaring events at all frequencies with doubling time scale of the TeV and X-ray flux on the order of minutes, and such rapid flaring events are hard to explain theoretically. We explore the effect of the synchrotron-self Compton cooling, which is inherently time-dependent, leading to a rapid cooling of the electrons. Having discussed intensively the resulting effects of this cooling scenario on the spectral energy distribution of blazars in previous papers, the effects of the time-dependent approach on the synchrotron lightcurve are investigated here. Taking into account the retardation due to the finite size of the source and the source geometry, we show that the time-dependent synchrotron-self Compton (SSC) cooling still has profound effects on the lightcurve compared to the usual linear (synchrotron and external Compton) cooling terms. This is most obvious if the SSC cooling takes lon...

  3. The synchrotron radiation angiography program at the national synchrotron light source

    International Nuclear Information System (INIS)

    The National Synchrotron Light Source (NSLS) angiography program is under development. The program is a collaboration between the Stanford University Angiography Project and the NSLS. A 180 m2 clinical facility has been built. A beam line is being constructed to utilize a superconducting wiggler radiation source. Projected start-up date for the NSLS program is Summer 1988

  4. ac Stark gradient echo memory in cold atoms

    International Nuclear Information System (INIS)

    The burgeoning fields of quantum computing and quantum key distribution have created a demand for a quantum memory. The gradient echo memory scheme is a quantum memory candidate for light storage that can boast efficiencies approaching unity, as well as the flexibility to work with either two- or three-level atoms. The key to this scheme is the frequency gradient that is placed across the memory. Currently, the three-level implementation uses a Zeeman gradient and warm atoms. In this article we model an alternate gradient-creation mechanism--the ac Stark effect--to provide an improvement in the flexibility of gradient-creation and field-switching times. We propose this scheme in concert with a move to cold atoms (≅1 mK). These temperatures would increase the storage times possible, and the small ensemble volumes would enable large ac Stark shifts with reasonable laser power. We find that memory bandwidths on the order of MHz can be produced with experimentally achievable laser powers and trapping volumes, with high precision in gradient creation and switching times on the order of nanoseconds possible. By looking at the different decoherence mechanisms present in this system, we determine that coherence times on the order of tens of milliseconds are possible, as are delay-bandwidth products of approximately 50 and efficiencies over 90%.

  5. Study on vacuum brazing of high purity alumina for application in proton synchrotron

    International Nuclear Information System (INIS)

    Highlights: • Study compares Mo–Mn metallization and active brazing routes for joining alumina. • Targeted application: UHV chamber of proton synchrotron. • Both kinds of joints were UHV compatible with helium leak rate <1.1 × 10−10 mbar l/s. • Active brazed joints met tensile and flexural strength design requirement (>50 MPa). • Active brazing is a simpler and economical route for joining high purity alumina. - Abstract: The paper describes an experimental study to evaluate two different vacuum brazing processes to obtain high purity alumina (99.7%) joints suitable for application in rapid cycle proton synchrotron. Two different brazing routes, adopted for making alumina–alumina brazed joints, included (i) multi-step Mo–Mn metallization, followed by brazing with BVAg-8 alloy and (ii) advanced single-step active brazing with CuSil-ABA® alloy. Both the brazing routes yielded helium leak tight and ultra-high vacuum (pressure < 10−9 mbar) compatible joints. Active-brazed specimens exhibited tensile and mean flexural strengths of 62 and 110 MPa, respectively. Metallized-brazed specimens, although associated with relatively lower tensile strength (35 MPa) than the targeted value (>50 MPa), displayed higher mean flexural strength of 149 MPa. The results of the study demonstrated that active brazing is a simple and cost effective alternative to conventional multi-step metallization route for producing quality joints of high purity alumina for application in rapid cycle proton synchrotron machine

  6. Looking Back at International Synchrotron Radiation Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Gwyn

    2012-03-01

    With the 11th International Synchrotron Radiation Instrumentation coming up in July 2012 in Lyons, France, we thought it might be of interest to our readers to review all the past meetings in this series. We thank Denny Mills of the APS, Argonne for putting the list together. Prior to these larger meetings, and in the early days, facilities held their own meetings similar to the user meetings of today. However, the meeting held at ACO in Orsay, France in 1977 was the first such meeting with an international flavor and so it is on the list. However it is not counted as number 1 since it was agreed way back to start the numbering with the 1982 DESY meeting. The 2005 USA National Meeting scheduled at CAMD in Baton Rouge had to be canceled due to Hurricane Katrina. It was ultimately held in 2007, with the CLS hosted meeting the following year. And a personal note from the magazine - Synchrotron Radiation News was born at the 1987 meeting in Madison, Wisconsin with a proposal that was put to a special session of the meeting organized by Susan Lord. Initial proposals were to model it after the CERN Courier, but it soon adopted its own distinct flavor.

  7. Status of the SOLEIL Booster Synchrotron

    CERN Document Server

    Loulergue, Alexandre

    2005-01-01

    SOLEIL is a 2.75 GeV third generation synchrotron radiation facility under construction near Paris. The injection system is composed of a 100 MeV electron Linac pre-accelerator followed by a full energy (2.75 GeV) booster synchrotron. The booster lattice is based on a FODO structure with missing magnet. With a circumference of 157 m and low field magnets (0.74 T), the emittance is of 150 nm.rad at 2.75 GeV. A flexible and economic ramping switched mode procedure for the main supply cycled up to 3 Hz and a 35 kW-352 MHz solid state amplifier powering the RF system are used. At present time, all the magnets, supports and vacuum have been received and tested. Half of the ring is already assembled and installation is the tunnel will begin in January 05. The pulsed elements and their pulser will be received and tested from January to April. The four main magnet power supplies will be received in February and tested in Marsh. We plan the booster commissioning with beam in May 2005.

  8. Ferroelectrics under the Synchrotron Light: A Review

    Directory of Open Access Journals (Sweden)

    Luis E. Fuentes-Cobas

    2015-12-01

    Full Text Available Currently, an intensive search for high-performance lead-free ferroelectric materials is taking place. ABO3 perovskites (A = Ba, Bi, Ca, K and Na; B = Fe, Nb, Ti, and Zr appear as promising candidates. Understanding the structure–function relationship is mandatory, and, in this field, the roles of long- and short-range crystal orders and interactions are decisive. In this review, recent advances in the global and local characterization of ferroelectric materials by synchrotron light diffraction, scattering and absorption are analyzed. Single- and poly-crystal synchrotron diffraction studies allow high-resolution investigations regarding the long-range average position of ions and subtle global symmetry break-downs. Ferroelectric materials, under the action of electric fields, undergo crystal symmetry, crystallite/domain orientation distribution and strain condition transformations. Methodological aspects of monitoring these processes are discussed. Two-dimensional diffraction clarify larger scale ordering: polycrystal texture is measured from the intensities distribution along the Debye rings. Local order is investigated by diffuse scattering (DS and X-ray absorption fine structure (XAFS experiments. DS provides information about thermal, chemical and displacive low-dimensional disorders. XAFS investigation of ferroelectrics reveals local B-cation off-centering and oxidation state. This technique has the advantage of being element-selective. Representative reports of the mentioned studies are described.

  9. Synchrotron radiation from a Helical Wiggler

    International Nuclear Information System (INIS)

    The use of Wiggler magnets as an improved source of synchrotron radiation from high energy electron storage rings was proposed a few years ago. Since then it has also been suggested that synchrotron radiation from Wiggler magnets placed in proton machines can be used to monitor energy, dimensions and position of the beam and that this effect is even more interesting in proton storage rings where the need to see the beam is greater. Most of the calculations carried out so far consider radiation from a single particle in a Wiggler which is appropriate when the beam is radiating incoherently. In this paper a general formalism is developed for the case when the beam radiates coherently. These results are then applied to both electron and proton storage rings. For the electron case, an expression is derived for the length of the bunch to be used as a more intense coherent radiation source. For proton machines the radiation can be used to measure energy, current, transverse dimensions and longitudinal density variations in the beam

  10. Synchrotrons for hadron therapy: Part I

    CERN Document Server

    Badano, L; Bryant, P; Crescenti, M; Holy, P; Knaus, P; Maier, A; Pullia, M; Rossi, S

    1999-01-01

    The treatment of cancer with accelerator beams has a long history with betatrons, linacs, cyclotrons and now synchrotrons being exploited for this purpose. Treatment techniques can be broadly divided into the use of spread-out beams and scanned 'pencil' beams. The Bragg-peak behaviour of hadrons makes them ideal candidates for the latter. The combination of precisely focused 'pencil' beams with controllable penetration (Bragg peak) and high, radio-biological efficiency (light ions) opens the way to treating the more awkward tumours that are radio-resistant, complex in shape and lodged against critical organs. To accelerate light ions (probably carbon) with pulse-to-pulse energy variation, a synchrotron is the natural choice. The beam scanning system is controlled via an on-line measurement of the particle flux entering the patient and, for this reason, the beam spill must be extended in time (seconds) by a slow-extraction scheme. The quality of the dose intensity profile ultimately depends on the uniformity o...

  11. Synchrotrons for hadron therapy, part 1

    CERN Document Server

    Badano, L; Bryant, P J; Crescenti, M; Holy, P; Knaus, P; Maier, A T; Pullia, M; Rossi, S

    1999-01-01

    The treatment of cancer with accelerator beams has a long history with linacs, cyclotrons and now synchrotrons being exploited for this purpose. Treatment techniques can be broadly divided into the use of spread-out beams and scanned 'pencil' beams. The Bragg-peak behaviour of hadrons makes them ideal candidates for the latter. The combination of precisely focused 'pencil' beams with controllable penetration (Bragg peak) and high, radio-biological efficiency (light ions) opens the way to treating the more awkward tumours that are radio-resistant, complex in shape and lodged against critical organs. To accelerate light ions (probably carbon) with pulse-to-pulse energy variation, a synchrotron is the natural choice. The beam scanning system is controlled via an on-line measurement of the particle flux entering the patient and, for this reason, the beam spill must be extended in time (seconds) by a slow-extraction scheme. The quality of the dose intensity profile ultimately depends on the uniformity of the beam ...

  12. Berkeley Lab's ALS generates femtosecond synchrotron radiation

    CERN Document Server

    Robinson, A L

    2000-01-01

    A team at Berkeley's Advanced Light Source has shown how a laser time-slicing technique provides a path to experiments with ultrafast time resolution. A Lawrence Berkeley National Laboratory team has succeeded in generating 300 fs pulses of synchrotron radiation at the ALS synchrotron radiation machine. The team's members come from the Materials Sciences Division (MSD), the Center for Beam Physics in the Accelerator and Fusion Research Division and the Advanced Light Source (ALS). Although this proof-of principle experiment made use of visible light on a borrowed beamline, the laser "time-slicing" technique at the heart of the demonstration will soon be applied in a new bend magnet beamline that was designed specially for the production of femtosecond pulses of X-rays to study long-range and local order in condensed matter with ultrafast time resolution. An undulator beamline based on the same technique has been proposed that will dramatically increase the flux and brightness. The use of X-rays to study the c...

  13. Application of circular polarized synchrotron radiation

    International Nuclear Information System (INIS)

    The idea of using the polarizing property of light for physical experiment by controlling it variously has been known from old time, and the Faraday effect and the research by polarizing microscopy are its examples. The light emitted from the electron orbit of an accelerator has the different polarizing characteristics from those of the light of a laboratory light source, and as far as observing it within the electron orbit plane, it becomes linearly polarized light. By utilizing this property well, research is carried out at present in synchrotron experimental facilities. Recently, the technology related to the insert type light cources using permanent magnets has advanced remarkably, and circular polarized light has become to be producible. If the light like this can be obtained with the energy not only in far ultraviolet region but also to x-ray region at high luminance, new possibility should open. At the stage that the design of an insert type light source was finished, and its manufacture was started, the research on the method of evaluating the degree of circular polarization and the research on the utilization of circular polarized synchrotron radiation are earnestly carried out. In this report, the results of researches presented at the study meeting are summarized. Moreover, the design and manufacture of the beam lines for exclusive use will be carried out. (Kako, I.)

  14. Mapping prehistoric ghosts in the synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, N.P.; Wogelius, R.A. [University of Manchester, School of Earth, Atmospheric, and Environmental Sciences, Manchester (United Kingdom); University of Manchester, Williamson Research Centre for Molecular Environmental Science, Manchester (United Kingdom); Bergmann, U. [SLAC National Accelerator Laboratory, Linac Coherent Light Source, Menlo Park, CA (United States); Larson, P. [Black Hills Institute of Geological Research, Inc., Hill City, SD (United States); Sellers, W.I. [University of Manchester, Faculty of Life Sciences, Manchester (United Kingdom); Manning, P.L. [University of Manchester, School of Earth, Atmospheric, and Environmental Sciences, Manchester (United Kingdom); University of Manchester, Williamson Research Centre for Molecular Environmental Science, Manchester (United Kingdom); University of Pennsylvania, Department of Earth and Environmental Science, Philadelphia, PA (United States)

    2013-04-15

    The detailed chemical analysis of fossils has the potential to reveal great insight to the composition, preservation and biochemistry of ancient life. Such analyses would ideally identify, quantify, and spatially resolve the chemical composition of preserved bone and soft tissue structures, but also the embedding matrix. Mapping the chemistry of a fossil in situ can place constraints on mass transfer between the enclosing matrix and the preserved organism(s), and therefore aid in distinguishing taphonomic processes from original chemical zonation remnant within the fossils themselves. Conventional analytical methods, such as scanning electron microscopy (SEM) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) have serious limitations in this case, primarily, an inability to provide large (i.e., decimeter) scale chemical maps. Additionally, vacuum chamber size and the need for destructive sampling preclude analysis of large and precious fossil specimens. However, the recent development of Synchrotron Rapid Scanning X-ray Fluorescence (SRS-XRF) at the Stanford Synchrotron Radiation Lightsource (SSRL) allows the non-destructive chemical analysis and imaging of major, minor, and trace element concentrations of large paleontological and archeological specimens in rapid scanning times. Here we present elemental maps of a fossil reptile produced using the new SRS-XRF method. Our results unequivocally show that preserved biological structures are not simply impressions or carbonized remains, but possess a remnant of the original organismal biochemistry. We show that SRS-XRF is a powerful new tool for the study of paleontological and archaeological samples. (orig.)

  15. Physics design of SSRF synchrotron radiation security

    Institute of Scientific and Technical Information of China (English)

    XU Yi; DAI Zhi-Min; LIU Gui-Min

    2009-01-01

    High brightness of SSRF brings about synchrotron radiation security problems,which will be solved in physics design.The main radiations are generated from bending magnets and insertion devices.Since the fact that radiation power and radiating area are different in these two kinds of synchrotron radiation,the arrangements of photon absorbers,diaphragms and other vacuum components need to be treated distinctively.In addition.SSRF interlock protection threshold is defined and the beam orbit in the straight line is limited.Hence.beam orbit in the bending magnets and IDs are also restricted by the threshold.The orbit restriction is calculated and helps us to arrange the vacuum components.In this paper,beam orbit distortion restricted by interlock protection threshold,radiation power,radiation angle and illuminating area are calculated.From the calculation results,the physics designs in manufacture and installation vacuum components are put forward.By commissioning,it is shown that physics requirements are met rigidly in the engineering process.

  16. Synchrotron Facilities and Free Electron Lasers

    Energy Technology Data Exchange (ETDEWEB)

    Vaclav, Vylet; /Duke U.; Liu, James; /SLAC

    2007-12-21

    Synchrotron radiation (SR) is electromagnetic radiation emitted when a charged particle travels along a curved trajectory. Initially encountered as a nuisance around orbits of high energy synchrotron accelerators, it gradually became an indispensable research tool in many applications: crystallography, X-ray lithography, micromechanics, structural biology, microprobe X-ray experiments, etc. So-called first generation SR sources were exploiting SR in parasitic mode at electron accelerators built to study particle collisions. The second generation of SR sources was the first facilities solely devoted to SR production. They were optimized to achieve stable high currents in the accelerator ring to achieve substantially higher photon flux and to provide a large number of SR beam lines for users. Third generation sources were further optimized for increased brilliance, i.e. with photons densely packed into a beam of very small cross-sectional area and minimal angular divergence (see the Appendix for more detailed definitions of flux, brightness and brilliance) and makes extensive use of the insertion devices such as wigglers and undulators. Free Electron Lasers (FELs), the fourth generation SR sources, open new research possibilities by offering extremely short pulses of extremely bright and coherent radiation. The number of SR sources around the world now probably exceeds 100. These facilities vary greatly in size, energy of the electron (or positron) beams, range of photon energies and other characteristics of the photon beams produced. In what follows we will concentrate on describing some common aspects of SR facilities, their operation modes and specific radiation protection aspects.

  17. Performances of BNL high-intensity synchrotrons

    International Nuclear Information System (INIS)

    The AGS proton synchrotron was completed in 1960 with initial intensity in the 10 to the 10th power proton per pulse (ppp) range. Over the years, through many upgrades and improvements, the AGS now reached an intensity record of 6.3 x 1013 ppp, the highest world intensity record for a proton synchrotron on a single pulse basis. At the same time, the Booster reached 2.2 x 1013 ppp surpassing the design goal of 1.5 x 1013 ppp due to the introduction of second harmonic cavity during injection. The intensity limitation caused by space charge tune spread and its relationship to injection energy at 50 MeV, 200 MeV, and 1,500 MeV will be presented as well as many critical accelerator manipulations. BNL currently participates in the design of an accumulator ring for the SNS project at Oak Ridge. The status on the issues of halo formation, beam losses and collimation are also presented

  18. Thermal loading considerations for synchrotron radiation mirrors

    International Nuclear Information System (INIS)

    Grazing incidence mirrors used to focus synchrotron radiation beams through small distant apertures have severe optical requirements. The surface distortion due to heat loading of the first mirror in a bending magnet beam line is of particular concern when a large fraction of the incident beam is absorbed. In this paper we discuss mirror design considerations involved in minimizing the thermal/mechanical loading on vertically deflecting first surface mirrors required for SPEAR synchrotron radiation beam lines. Topics include selection of mirror material and cooling method, the choice of SiC for the substrate, optimization of the thickness, and the design of the mirror holder and cooling mechanism. Results obtained using two-dimensional, finite-element thermal/mechanical distortion analysis are presented for the case of a 60 grazing incidence SiC mirror absorbing up to 260 W at Beam Line VIII on the SPEAR ring. Test descriptions and results are given for the material used to thermally couple this SiC mirror to a water-cooled block. The interface material is limited to applications for which the equivalent normal heat load is less than 20 W/cm2

  19. Energy alternatives

    International Nuclear Information System (INIS)

    Due to sharp rise in oil proces after the 1973 Arab-Israeli War, world attention has been focussed on the energy problem. At present the energy problem is limited to the cost and reliability of supply, even though there are enough supplies to go round. However, in the future the problem will be of availability, because in spite of the full exploitation of currently available conventional energy sources, the supply will fall short of demand which will always be increasing. Hence, there is need to develop alternate energy sources, including fast breeder reactors, fusion reactors and MHD. Economic and technical aspects of these energy are discussed. (M.G.B.)

  20. Alternative detente

    International Nuclear Information System (INIS)

    The influence of the Chernobyl accident on the disarmament and anti-nuclear movements is discussed. The accident directed attention towards the areas in common rather than the areas of disagreement. It also demonstrated the environmental impact of radioactivity, strengthening the ecological case of the anti-nuclear movement. The issues are discussed for the Western and Eastern bloc countries and the relationship between the two. Sections focus on the Eco-protest, Green politics and economics and on the politics of minority protest and the Green alternative. (U.K.)

  1. Dual-rail optical gradient echo memory

    CERN Document Server

    Higginbottom, Daniel B; Campbell, Geoff T; Hosseini, Mahdi; Cao, Ming Tao; Sparkes, Ben M; Bernu, Julian; Robins, Nick P; Lam, Ping Koy; Buchler, Ben C

    2016-01-01

    We introduce a scheme for the parallel storage of frequency separated signals in an optical memory and demonstrate that this dual-rail storage is a suitable memory for high fidelity frequency qubits. The two signals are stored simultaneously in the Zeeman-split Raman absorption lines of a cold atom ensemble using gradient echo memory techniques. Analysis of the split-Zeeman storage shows that the memory can be configured to preserve the relative amplitude and phase of the frequency separated signals. In an experimental demonstration dual-frequency pulses are recalled with 35% efficiency, 82% interference fringe visibility, and 6 degrees phase stability. The fidelity of the frequency-qubit memory is limited by frequency-dependent polarisation rotation and ambient magnetic field fluctuations, our analysis describes how these can be addressed in an alternative configuration.

  2. Transformational acoustic metamaterials based on pressure gradients

    CERN Document Server

    García-Meca, C; Barceló, C; Jannes, G; Sánchez-Dehesa, J; Martínez, A

    2014-01-01

    We apply a homogenization process to the acoustic velocity potential wave equation. The study of various examples shows that the resulting effective properties are different from those of the homogenized pressure wave equation for the same underlying acoustic parameters. A careful analysis reveals that a given set of inhomogeneous parameters represents an entirely different physical system depending on the considered equation. Our findings unveil a different way of tailoring acoustic properties through gradients of the static pressure. In contrast to standard metafluids based on isobaric composites, this alternative kind of metafluids is suitable for the implementation of transformational devices designed via the velocity potential equation. This includes acoustic systems in a moving background or arising from general space-time transformations. As an example, we design a device able to cloak the acoustic velocity potential.

  3. Alternative crops

    International Nuclear Information System (INIS)

    Surplus cereal production in the EEC and decreasing product prices, mainly for cereals, has prompted considerable interest for new earnings in arable farming. The objective was to examine whether suggested new crops (fibre, oil, medicinal and alternative grains crops) could be considered as real alternatives. Whether a specific crop can compete economically with cereals and whether there is a market demand for the crop is analyzed. The described possibilities will result in ca. 50,000 hectares of new crops. It is expected that they would not immediately provide increased earnings, but in the long run expected price developments are more positive than for cereals. The area for new crops will not solve the current surplus cereal problem as the area used for new crops is only 3% of that used for cereals. Preconditions for many new crops is further research activities and development work as well as the establishment of processing units and organizational initiatives. Presumably, it is stated, there will then be a basis for a profitable production of new crops for some farmers. (AB) (47 refs.)

  4. For the first time: Moessbauer effect with synchrotron radiation

    International Nuclear Information System (INIS)

    After 9 years of preparation a group of scientists under the leadership of Prof. Erich Gerdau from the University of Hamburg succeeded in observing the Moessbauer Effect (recoilless emission of a gamma quantum) with the help of synchrotron radiation in October last year. The experiments were carried out at the Hamburg Synchrotron Radiation Laboratory, HASYLAB, at the DORIS II storage ring. (orig.)

  5. Synchrotron radiation in art and archaeology SRA 2005

    Energy Technology Data Exchange (ETDEWEB)

    Pollard, A.M.; Janssens, K.; Artioli, G.; Young, M.L.; Casadio, F.; Schnepp, S.; Marvin, J.; Dunand, D.C.; Almer, J.; Fezzaa, K.; Lee, W.K.; Haeffner, D.R.; Reguer, S.; Dillmann, Ph.; Mirambet, F.; Susini, J.; Lagarde, P.; Pradell, T.; Molera, J.; Brunetti, B.; D' acapito, F.; Maurizio, C.; Mazzoldi, P.; Padovani, S.; Sgamellotti, A.; Garges, F.; Etcheverry, M.P.; Flank, A.M.; Lagarde, P.; Marcus, M.A.; Scheidegger, A.M.; Grolimund, D.; Pallot-Frossard, I.; Smith, A.D.; Jones, M.; Gliozzo, E.; Memmi-Turbanti, I.; Molera, J.; Vendrell, M.; Mcconachie, G.; Skinner, T.; Kirkman, I.W.; Pantos, E.; Wallert, A.; Kanngiesser, B.; Hahn, O.; Wilke, M.; NekaT, B.; Malzer, W.; Erko, A.; Chalmin, E.; Vignaud, C.; Farges, F.; Susini, J.; Menu, M.; Sandstrom, M.; Cotte, M.; Kennedy, C.J.; Wess, T.J.; Muller, M.; Murphy, B.; Roberts, M.A.; Burghammer, M.; Riekel, C.; Gunneweg, J.; Pantos, E.; Dik, J.; Tafforeau, P.; Boistel, R.; Boller, E.; Bravin, A.; Brunet, M.; Chaimanee, Y.; Cloetens, P.; Feist, M.; Hoszowska, J.; Jaeger, J.J.; Kay, R.F.; Lazzari, V.; Marivaux, L.; Nel, A.; Nemoz, C.; Thibault, X.; Vignaud, P.; Zabler, S.; Sciau, P.; Goudeau, P.; Tamura, N.; Doormee, E.; Kockelmann, W.; Adriaens, A.; Ryck, I. de; Leyssens, K.; Hochleitner, B.; Schreiner, M.; Drakopoulos, M.; Snigireva, I.; Snigirev, A.; Sanchez Del Rio, M.; Martinetto, P.; Dooryhee, E.; Suarez, M.; Sodo, A.; Reyes-Valerio, C.; Haro Poniatowski, E.; Picquart, M.; Lima, E.; Reguera, E.; Gunneweg, J.; Reiche, I.; Berger, A.; Bevers, H.; Duval, A

    2005-07-01

    Materials - bones, artifacts, artwork,.... - lie at the heart of both archaeology and art conservation. Synchrotron radiation techniques provide powerful ways to interrogate these records of our physical and cultural past. In this workshop we will discuss and explore the current and potential applications of synchrotron radiation science to problems in archaeology and art conservation. This document gathers the abstracts of the presentations.

  6. A synchrotron radiation facility for x-ray astronomy

    DEFF Research Database (Denmark)

    Hall, C.J.; Lewis, R.A.; Christensen, Finn Erland;

    1997-01-01

    A proposal for an x-ray optics test facility based at a synchrotron radiation source is presented. The facility would incorporate a clean preparation area, and a large evacuable test area. The advantages of using a synchrotron as the source of the test radiation are discussed. These include the a...

  7. Synchrotron radiation in art and archaeology SRA 2005

    International Nuclear Information System (INIS)

    Materials - bones, artifacts, artwork,.... - lie at the heart of both archaeology and art conservation. Synchrotron radiation techniques provide powerful ways to interrogate these records of our physical and cultural past. In this workshop we will discuss and explore the current and potential applications of synchrotron radiation science to problems in archaeology and art conservation. This document gathers the abstracts of the presentations

  8. Simulation of a Microfluidic Gradient Generator using Lattice Boltzmann Methods

    CERN Document Server

    Simon, Tanaka

    2013-01-01

    Microfluidics provides a powerful and versatile technology to accurately control spatial and temporal conditions for cell culturing and can therefore be used to study cellular responses to gradients. Here we use Lattice Boltzmann methods (LBM) to solve both the Navier-Stokes equation (NSE) for the fluid and the coupled convection-diffusion equation (CDE) for the compounds that form the diffusion-based gradient. The design of a microfluidic chamber for diffusion-based gradients must avoid flow through the cell chamber. This can be achieved by alternately opening the source and the sink channels. The fast toggling of microfluidic valves requires switching between different boundary conditions. We demonstrate that the LBM is a powerful method for handling complex geometries, high Peclet number conditions, discontinuities in the boundary conditions, and multiphysics coupling.

  9. The influence of ALN-Al gradient material gradient index on ballistic performance

    International Nuclear Information System (INIS)

    Ballistic performance of the gradient material is superior to laminated material, and gradient materials have different gradient types. Using ls-dyna to simulate the ballistic performance of ALN-AL gradient target plates which contain three gradient index (b = 1, b = 0.5, b = 2). Through Hopkinson bar numerical simulation to the target plate materials, we obtained the reflection stress wave and transmission stress wave state of gradient material to get the best gradient index. The internal stress state of gradient material is simulated by amplification processing of the target plate model. When the gradient index b is equal to 1, the gradient target plate is best of all.

  10. The influence of ALN-Al gradient material gradient index on ballistic performance

    Science.gov (United States)

    Wang, Youcong; Liu, Qiwen; Li, Yao; Shen, Qiang

    2013-03-01

    Ballistic performance of the gradient material is superior to laminated material, and gradient materials have different gradient types. Using ls-dyna to simulate the ballistic performance of ALN-AL gradient target plates which contain three gradient index (b = 1, b = 0.5, b = 2). Through Hopkinson bar numerical simulation to the target plate materials, we obtained the reflection stress wave and transmission stress wave state of gradient material to get the best gradient index. The internal stress state of gradient material is simulated by amplification processing of the target plate model. When the gradient index b is equal to 1, the gradient target plate is best of all.

  11. Activity report of Synchrotron Radiation Laboratory 2000

    International Nuclear Information System (INIS)

    In the spring of 2000, the Synchrotron Radiation Laboratory (SRL) moved from Tanashi to Kashiwa Campus. Now, most important for SRL is to promote the future project of High-brilliance Light Source, Super SOR project, in cooperation with the nationwide user group as well as with the users of the University of Tokyo. The Super SOR will be one of the most brilliant light sources in vacuum ultraviolet and soft x-ray regimes. In order to continue extensive efforts on research and developments (R and D) of the light source and beamlines, the SRL Experimental Building has been built at Kashiwa Campus, which acts as the Super SOR Project Office of the University of Tokyo. On the other hand, the SRL has a branch laboratory in the High Energy Accelerator Research Organization (KEK) at Tsukuba. The branch laboratory maintains an undulator called Revolver, two beamlines and three experimental stations (BL-18A, 19A and 19B); they are installed in the Photon Factory (PF) and fully opened to outside users. The in-house staffs not only serve the outside users with technical support and advices, but also carry out their own research works on advanced solid state spectroscopy as well as instrumentation. In the fiscal year of 2000, the operation time of the beamlines wag more than 5000 hours and the number of the users was more than 200. The main scientific interests and activities in the SRL at KEK-PF are directed to the electronic structures of new materials with new transport and optical properties. The electronic structures of solid surfaces and interfaces are also intensively studied. The study of the behavior of electrons in a synchrotron radiation source is indispensable as a part of accelerator physics for developing electron accelerators. The SRL is carrying out research works of the accelerator physics and developing the accelerator-related technology, many parts of which will be directly applied to the Super SOR light source. This report contains the activities of the SRL

  12. Energy alternatives

    International Nuclear Information System (INIS)

    English. A special committe of the Canadian House of Commons was established on 23 May 1980 to investigate the use of alternative energy sources such as 'gasohol', liquified coal, solar energy, methanol, wind and tidal power, biomass, and propane. In its final report, the committee envisions an energy system for Canada based on hydrogen and electricity, using solar and geothermal energy for low-grade heat. The committe was not able to say which method of generating electricty would dominate in the next century, although it recommends that fossil fuels should not be used. The fission process is not specifically discussed, but the outlook for fusion was investigated, and continued governmental support of fusion research is recommended. The report proposes some improvements in governmental energy organizations and programs

  13. Gradient expansion for anisotropic hydrodynamics

    CERN Document Server

    Florkowski, Wojciech; Spaliński, Michał

    2016-01-01

    We compute the gradient expansion for anisotropic hydrodynamics. The results are compared with the corresponding expansion of the underlying kinetic-theory model with the collision term treated in the relaxation time approximation. We find that a recent formulation of anisotropic hydrodynamics based on an anisotropic matching principle yields the first three terms of the gradient expansion in agreement with those obtained for the kinetic theory. This gives further support for this particular hydrodynamic model as a good approximation of the kinetic-theory approach. We further find that the gradient expansion of anisotropic hydrodynamics is an asymptotic series, and the singularities of the analytic continuation of its Borel transform indicate the presence of non-hydrodynamic modes.

  14. The Interaction of CuS and Halothiobacillus HT1 Biofilm in Microscale Using Synchrotron Radiation-Based Techniques

    OpenAIRE

    Huirong Lin; Guangcun Chen; Shenhai Zhu; Yingxu Chen; Dongliang Chen; Wei Xu; Xiaohan Yu; Jiyan Shi

    2013-01-01

    In order to investigate the microbe-mineral interaction in the micro scale, spatial distribution and speciation of Cu and S in Halothiobacillus HT1 biofilm formed on a CuS surface was examined using synchrotron-based X-ray techniques. Confocal laser scanning microscope (CLSM) results indicated that Halothiobacillus HT1 biofilm formation gave rise to distinct chemical and redox gradients, leading to diverse niches in the biofilm. Live cells were distributed at the air-biofilm and membrane-biof...

  15. Research and Development for Ultra-High Gradient Accelerator Structures

    Science.gov (United States)

    Tantawi, Sami G.; Dolgashev, Valery; Higashi, Yasuo; Spataro, Bruno

    2010-11-01

    Research on the basic physics of high-gradient, high frequency accelerator structures and the associated RF/microwave technology are essential for the future of discovery science, medicine and biology, energy and environment, and national security. We will review the state-of-the-art for the development of high gradient linear accelerators. We will present the research activities aimed at exploring the basic physics phenomenon of RF breakdown. We present the experimental results of a true systematic study in which the surface processing, geometry, and materials of the structures have been varied, one parameter at a time. The breakdown rate or alternatively, the probability of breakdown/pulse/meter has been recorded for different operating parameters. These statistical data reveal a strong dependence of breakdown probability on surface magnetic field, or alternatively on surface pulsed heating. This is in contrast to the classical view of electric field dependence.

  16. Quadrupole magnet for a rapid cycling synchrotron

    International Nuclear Information System (INIS)

    Rapid Cycling Synchrotrons (RCS) feature interleaved warm and cold dipole magnets; the field of the warm magnets is used to modulate the average bending field depending on the particle energy. It has been shown that RCS can be an attractive option for fast acceleration of particles, for example, muons, which decay quickly. In previous studies it was demonstrated that in principle warm dipole magnets can be designed which can provide the required ramp rates, which are equivalent to frequencies of about 1 kHz. To reduce the losses it is beneficial to employ two separate materials for the yoke; it was also shown that by employing an optimized excitation coil geometry the eddy current losses are acceptable. In this paper we show that the same principles can be applied to quadrupole magnets targeting 30 T/m with a repetition rate of 1kHz and good field quality.

  17. Quadrupole magnet for a rapid cycling synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Witte, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    Rapid Cycling Synchrotrons (RCS) feature interleaved warm and cold dipole magnets; the field of the warm magnets is used to modulate the average bending field depending on the particle energy. It has been shown that RCS can be an attractive option for fast acceleration of particles, for example, muons, which decay quickly. In previous studies it was demonstrated that in principle warm dipole magnets can be designed which can provide the required ramp rates, which are equivalent to frequencies of about 1 kHz. To reduce the losses it is beneficial to employ two separate materials for the yoke; it was also shown that by employing an optimized excitation coil geometry the eddy current losses are acceptable. In this paper we show that the same principles can be applied to quadrupole magnets targeting 30 T/m with a repetition rate of 1kHz and good field quality.

  18. New Synchrotron Radiation Center beamlines at Aladdin

    International Nuclear Information System (INIS)

    In the past year, the Synchrotron Radiation Center (SRC) staff has installed five new beamlines at SRC. Three of these beamlines are ''public'' beamlines operated by SRC for experiments selected from peer-reviewed proposals. Fifty to seventy-five percent of the experimental time on the other two beamlines is managed by the SRC as a consequence of the SRC being a partner in participating research teams (PRTs). These new beamlines bring the number of VUV and soft x-ray research beamlines installed on Aladdin to 17 as of August 1988. Including two storage ring optical diagnostic ports, there will be 20 ports in use on Aladdin by the end of 1988

  19. Coherent synchrotron radiation experiments for the LCLS

    International Nuclear Information System (INIS)

    The authors describe a coherent synchrotron radiation experiment planned at Los Alamos to support the design of the Linac Coherent Light Source (LCLS) x-ray FEL. Preliminary simulations of the LCLS compressors show that a clever tuning strategy can be used to minimize the electron's beam emittance growth due to noninertial space-charge forces by employing a delicate cancellation of these forces. The purpose of the Los Alamos experiment, using a sub-picosecond chicane compressor, is to benchmark these simulations tools. In this paper, the authors present detailed numerical simulations of the experiment, and point out unique signatures of this effect that are measurable. As predicted previously, the largest emittance growths and induced energy spreads result from the nonradiative components of this space-charge force

  20. Optical substrate materials for synchrotron radiation beamlines

    Energy Technology Data Exchange (ETDEWEB)

    Howells, M.R. [Lawrence Berkeley National Lab., CA (United States). Advanced Light Source; Paquin, R.A. [Univ. of Arizona, Tucson, AZ (United States). Optical Sciences Center

    1997-06-01

    The authors consider the materials choices available for making optical substrates for synchrotron radiation beam lines. They find that currently the optical surfaces can only be polished to the required finish in fused silica and other glasses, silicon, CVD silicon carbide, electroless nickel and 17-4 PH stainless steel. Substrates must therefore be made of one of these materials or of a metal that can be coated with electroless nickel. In the context of material choices for mirrors they explore the issues of dimensional stability, polishing, bending, cooling, and manufacturing strategy. They conclude that metals are best from an engineering and cost standpoint while the ceramics are best from a polishing standpoint. They then give discussions of specific materials as follows: silicon carbide, silicon, electroless nickel, Glidcop{trademark}, aluminum, precipitation-hardening stainless steel, mild steel, invar and superinvar. Finally they summarize conclusions and propose ideas for further research.

  1. Optical substrate materials for synchrotron radiation beamlines

    International Nuclear Information System (INIS)

    The authors consider the materials choices available for making optical substrates for synchrotron radiation beam lines. They find that currently the optical surfaces can only be polished to the required finish in fused silica and other glasses, silicon, CVD silicon carbide, electroless nickel and 17-4 PH stainless steel. Substrates must therefore be made of one of these materials or of a metal that can be coated with electroless nickel. In the context of material choices for mirrors they explore the issues of dimensional stability, polishing, bending, cooling, and manufacturing strategy. They conclude that metals are best from an engineering and cost standpoint while the ceramics are best from a polishing standpoint. They then give discussions of specific materials as follows: silicon carbide, silicon, electroless nickel, Glidcop trademark, aluminum, precipitation-hardening stainless steel, mild steel, invar and superinvar. Finally they summarize conclusions and propose ideas for further research

  2. A guide to synchrotron radiation science

    CERN Document Server

    Sato, Shigeru; Munro, Ian; Lodha, G S

    2015-01-01

    Synchrotron Radiation (SR), as a light source is now in use around the world to provide brilliant radiation from the infrared into the soft and hard X-ray regions. It is an indispensible and essential tool to establish the physic-chemical characteristics of materials and surfaces from an atomic and molecular view point. It is being applied to topics which range from mineralogy to protein crystallography, embracing research in areas from the physical to the life sciences. This new guide is a concise yet comprehensive and easily readable introduction to an expanding area of science. It presents in a readily assimilable form the basic concepts of SR science from its generation principles, through source design and operation to the principles of instruments for SR exploitation followed by a survey of its actual applications in selected research fields, including spectroscopy, diffractometry, microanalysis and chemical processing.

  3. Synchrotron radiation techniques. Extension to magnetism research

    International Nuclear Information System (INIS)

    Recently developed techniques using synchrotron radiation for the study of magnetism are reviewed. These techniques are based on X-ray absorption spectroscopy (XAS), and they exhibit significant advantages in element specificity. This is very important since the most attractive magnetic materials contain many magnetic elements, and those with small magnetic moments often play an essential role in the magnetic properties. Circularly polarized X-rays emitted from bending magnets or helical undulators allow us to perform magnetic circular dichroism measurements to reveal microscopic magnetic properties of various kinds of magnetic materials. X-ray absorption magnetic circular dichroism (XMCD) is discussed in detail. This technique provides unique information on orbital magnetic moments as well as spin magnetic moments, which are useful for the study of magnetic anisotropy. X-ray magnetic linear dichroism (XMLD) and X-ray resonant magnetic reflectometry (XRMR) techniques are also described. (author)

  4. Application of synchrotron radiation to submicron lithography

    International Nuclear Information System (INIS)

    Relevant features of modern X-ray sources suitable for submicron lithography with special emphasis on synchrotron with classical, normal and superconducting storage rings are compared. Capability of such sources for X-ray lithographic fabrication of 100 nm lines and 0.5 micron devices such as ULSI and multimegabit memory are discussed. Selecting the materials for X-ray mask substrate as well as the technique of patterning absorber material over it are extremely critical. Use of advanced techniques such as reactive ion etching, ion beam patterning and electron beam lithography for their fabrication is discussed. Characteristics of positive/negative X-ray resists such as sensitivity and resolution, critically governing their suitability in lithographic applications are compared. The technology of alignments recently adopted for X-ray lithography is presented. Submicron patterns and devices like CMOS, BPF and deep grooves featured through dedicated and commercial X-ray systems have been sampled. (author). 5 refs., 2 figs., 2 tabs

  5. 3D Detectors for Synchrotron Applications

    CERN Document Server

    Pennicard, D

    2009-01-01

    3D detectors are a novel variety of photodiode radiation detector, invented by Parker, Kenney and Segal (1997). Instead of having n- and p-type contacts on the front and back surfaces of a silicon substrate, like a standard photodiode, they have columns of doped material passing through the thickness of the silicon. This structure means that the detector can combine a reasonable substrate thickness with a very small electrode spacing, resulting in a low depletion voltage, fast charge collection and low charge sharing. These detectors have a couple of promising applications. Their fast charge collection and low depletion voltage should make them very radiation-tolerant. So, they could be used for future particle physics experiments at the Super Large Hadron Collider (SLHC), where high levels of radiation damage are expected. Also, their low charge sharing means they could potentially improve X-ray diffraction measurements at synchrotrons such as Diamond Light Source. This would allow these experiments, for exa...

  6. Discussion on spin-flip synchrotron radiation

    CERN Document Server

    Bordovitsyn, V A; Myagkii, A N

    1998-01-01

    Quantum spin-flip transitions are of great importance in the synchrotron radiation theory. For better understanding of the nature of this phenomenon, it is necessary to except the effects connected with the electric charge radiation from observation. This fact explains the suggested choice of the spin-flip radiation model in the form of radiation of the electric neutral Dirac-Pauli particle moving in the homogeneous magnetic field. It is known that in this case, the total radiation in the quantum theory is conditioned by spin-flip transitions. The idea is that spin-flip radiation is represented as a nonstationary process connected with spin precession. We shall shown how to construct a solution of the classical equation of the spin precession in the BMT theory having the exact solution of the Dirac-Pauli equation.Thus, one will find the connection of the quantum spin-flip transitions with classical spin precession.

  7. Status of Hiroshima Synchrotron Radiation Center

    International Nuclear Information System (INIS)

    The HSRC is a synchrotron radiation facility of Hiroshima University established in 1996. The HiSOR is a compact racetrack-type storage ring having 21.95 m circumference, therefore its natural emittance of 400 nmrad is not so small compared with the other medium ∼ large storage rings. The most outstanding advantage of the facility lies in good combination with beamlines for high-resolution photoelectron spectroscopy in energy range in VUV ∼ soft X-ray. We report the operation status of HiSOR and the present status of beamlines and experimental stations. The user time last year was achieved 1541 hours which was at the same level with those in the past several years because there was no serious trouble. (author)

  8. Silicon Pixel Detectors for Synchrotron Applications

    CERN Document Server

    Stewart, Graeme Douglas

    Recent advances in particle accelerators have increased the demands being placed on detectors. Novel detector designs are being implemented in many different areas including, for example, high luminosity experiments at the LHC or at next generation synchrotrons. The purpose of this thesis was to characterise some of these novel detectors. The first of the new detector types is called a 3D detector. This design was first proposed by Parker, Kenney and Segal (1997). In this design, doped electrodes are created that extend through the silicon substrate. When compared to a traditional photodiode with electrodes on the opposing surfaces, the 3D design can combine a reasonable detector thickness with a small electrode spacing resulting in fast charge collection and limited charge sharing. The small electrode spacing leads to the detectors having lower depletion voltages. This, combined with the fast collection time, makes 3D detectors a candidate for radiation hard applications. These applications include the upgra...

  9. Synchrotron radiation — 1873 to 1947

    Science.gov (United States)

    Blewett, John P.

    1988-04-01

    In 1873 Maxwell's treatise "Electricity and Magnetism" made it clear that a changing electric current will emit electromagnetic radiation. By the turn of the century, J.J. Thomson was showing that currents in space could be carried by electrons; accordingly, it was reasonable to believe that electrons, when accelerated, would radiate. By 1912, the theory of radiation from accelerated electrons was worked out and buried in the literature. Radiation from accelerated relativistic electrons did not come into prominence again until the 1940's when, finally, it was observed at the Research Laboratory of the General Electric Company. This paper will discuss the early theoretical treatments and will describe the first observations with the G.E. 100 MeV betatron and 75 MeV synchrotron.

  10. A Thick Target for Synchrotrons and Betatrons

    Science.gov (United States)

    McMillan, E. M.

    1950-09-19

    If a wide x-ray beam from an electron synchrotron or betatron is desired, in radiographic work with large objects for example, the usually very thin target may be replaced by a thick one, provided the resulting distortion of the x-ray spectrum due to multiple radiative processes is permissible. It is difficult to make the circulating electron beam traverse a thick target directly because of the small spacing between successive turns. Mounting a very thin beryllium, or other low-z material, fin on the edge of the thick target so that the fin projects into the beam will cause the beam to lose sufficient energy, and therefore radium, to strike the thick target the next time around. Sample design calculations are given.

  11. A program for synchrotron radiation dose calculations

    International Nuclear Information System (INIS)

    The computer program PHOTON was obtained from Brookhaven National Laboratory (courtesy D. Chapman, NSLS), and has now been installed at APS VAX. In the following a brief description of the program and how to access to it is described with an example. A detailed manual for the program is also available. The program is developed to calculate the transmitted and scattered spectra of the synchrotron radiation, as it passes through series of filters. The source can be a bending magnet or a wiggler. This can be generated for any bending magnet or a wiggler source by varying ring energy, the critical energy and opening angles of the radiation beam. Monochromatic beams to white radiation can be treated. Filter materials can be pure elements or composites. The absorption cross-sections of all elements for covering 10-2 to 106 keV are now included in a table, which can be accessed by giving the atomic symbol

  12. Application of synchrotron radiation in archaeology

    International Nuclear Information System (INIS)

    This paper reports current status of archaeological application of synchrotron radiation (SR). The advantages of SR in archaeological research and various application possibilities of X-ray powder diffraction (XPD), X-ray fluorescence (XRF) and X-ray absorption fine structure (XAFS) analyses of objects and materials of cultural heritage value are demonstrated through a number of case studies from literatures. They include XPD characterizations of Egyptian cosmetic powder, Attic Black Gloss, and pigments in Gothic altarpieces, provenance analysis of Old-Kutani china wares by high energy XRF, and XAFS analyses to reveal to origin of red color in Satsuma copper-ruby glass and role of iron in Maya blue. (author)

  13. Brightness of synchrotron radiation from wigglers

    CERN Document Server

    Geloni, Gianluca; Saldin, Evgeni

    2014-01-01

    According to literature, while calculating the brightness of synchrotron radiation from wigglers, one needs to account for the so called `depth-of-field' effects. In fact, the particle beam cross section varies along the wiggler. It is usually stated that the effective photon source size increases accordingly, while the brightness is reduced. Here we claim that this is a misconception originating from an analysis of the wiggler source based on geometrical arguments, regarded as almost self-evident. According to electrodynamics, depth-of-field effects do not exist: we demonstrate this statement both theoretically and numerically, using a well-known first-principle computer code. This fact shows that under the usually accepted approximations, the description of the wiggler brightness turns out to be inconsistent even qualitatively. Therefore, there is a need for a well-defined procedure for computing the brightness from a wiggler source. We accomplish this task based on the use of a Wigner function formalism. I...

  14. Helical magnetized wiggler for synchrotron radiation laser

    International Nuclear Information System (INIS)

    A helical magnetized iron wiggler has been built for a novel infrared synchrotron radiation laser (SRL) experiment. The wiggler consists of four periods of helical iron structure immersed in a solenoid field. This wiggler is to impart transverse velocity to a prebunched 6 MeV electron beam, and thus to obtain a desired high orbit pitch ratio for the SRL. Field tapering at beam entrance is considered and tested on a similar wiggler. Analytic and simulated characteristics of wigglers of this type are discussed and the performance of the fabricated wigglers is demonstrated experimentally. A 4.7 kG peak field was measured for a 6.4 mm air gap and a 5.4 cm wiggler period at a 20 kG solenoid field. The measured helical fields compare favorably with the analytical solution. This type of helical iron wigglers has the potential to be scaled to small periods with strong field amplitude

  15. Helical magnetized wiggler for synchrotron radiation laser

    CERN Document Server

    Wang Mei; Hirshfield, J L

    1999-01-01

    A helical magnetized iron wiggler has been built for a novel infrared synchrotron radiation laser (SRL) experiment. The wiggler consists of four periods of helical iron structure immersed in a solenoid field. This wiggler is to impart transverse velocity to a prebunched 6 MeV electron beam, and thus to obtain a desired high orbit pitch ratio for the SRL. Field tapering at beam entrance is considered and tested on a similar wiggler. Analytic and simulated characteristics of wigglers of this type are discussed and the performance of the fabricated wigglers is demonstrated experimentally. A 4.7 kG peak field was measured for a 6.4 mm air gap and a 5.4 cm wiggler period at a 20 kG solenoid field. The measured helical fields compare favorably with the analytical solution. This type of helical iron wigglers has the potential to be scaled to small periods with strong field amplitude.

  16. Control system for a compact synchrotron

    International Nuclear Information System (INIS)

    The control system for a compact superconducting synchrotron (HELIOS) is described. The machine is intended to be used as a prototype production tool for X-ray lithography, so emphasis has been placed on engineering the control system for this purpose. The system has been designed to be flexible for commissioning, but easy to use for an operator at a lithography facility. With this in mind the following facilities have been included: keys to limit control functions, a HELP facility for operators, colour touch-panels and displays, limits and other software protection. The conservative hardware design is based on well established CAMAC interfaces. Similarly, the software runs on a MicroVAX with VMS, is written in FORTRAN 77, and is adapted from a well developed SLAC control system. Design features include the use of local intelligence for some subsystems, modular hardware and software, interlocks and a central database. (orig.)

  17. X-ray stress measurement by use of synchrotron radiation source

    International Nuclear Information System (INIS)

    In the field of X-ray stress measurement of polycrystalline materials, a diffraction plane at higher Bragg angle has to be selected in order to obtain the precise value of stress. However, the stress measurement on an optional (hkl) plane desired is not always possible because the X-ray beam exited from a metal target has a dispersive wave length. Recently, we have been able to use the synchrotron radiation source (SR) as an excellent X-ray source. In Japan, the facility of synchrotron radiation (Photon Factory, PF) was constructed in the National Laboratory for High Energy Physics (KEK) at Tsukuba academic city. The use of this SR enables the stress measurements on many (hkl) planes with high accuracy in the higher Bragg angle region by providing an X-ray beam having an optional wave length. We have started the X-ray stress analysis by use of the synchrotron radiation source. This paper reports the system of measurement and some results of preliminaly experiments. Since a monochromatic X-ray beam is required for the stress measurement, we used a beam line which consists of a double crystal monochrometer and a focusing mirror. X-rays between 4 KeV (λ = 0.31 nm) and 10 KeV (λ = 0.12 nm) are available with this optical system. We adopted a constant Bragg angle of 2θ = 154 deg for all the diffraction planes. A PSPC having a carbon fiber anode is made and used as a detector with the use of a fast digital signal processor. We could observe the diffraction profiles from (200), (211), (220), (310) and (321) crystal plane of alpha iron, respectively, and the residual stresses in these planes except the (200) plane were measured with high accuracy in a short time. Such feature especially suits the stress analysis of the material which has preferred orientation or stress gradient. (author)

  18. Probing deformation substructure by synchrotron X-ray diffraction and dislocation dynamics modelling.

    Science.gov (United States)

    Korsunsky, Alexander M; Hofmann, Felix; Song, Xu; Eve, Sophie; Collins, Steve P

    2010-09-01

    Materials characterization at the nano-scale is motivated by the desire to resolve the structural aspects and deformation behavior at length scales relevant to those mechanisms that define the novel and unusual properties of nano-structured materials. A range of novel techniques has recently become accessible with the help of synchrotron X-ray beams that can be focused down to spot sizes of less than a few microns on the sample. The unique combination of tunability (energy selection), parallelism and brightness of synchrotron X-ray beams allows their use for high resolution diffraction (determination of crystal structure and transformations, analysis of dislocation sub-structures, orientation and texture analysis, strain mapping); small angle X-ray scattering (analysis of nano-scale voids and defects; orientation analysis) and imaging (radiography and tomography). After a brief review of the state-of-the-art capabilities for monochromatic and white beam synchrotron diffraction, we consider the usefulness of these techniques for the task of bridging the gap between experiment and modeling. Namely, we discuss how the experiments can be configured to provide information relevant to the validation and improvement of modeling approaches, and also how the results of various simulations can be post-processed to improve the possibility of (more or less) direct comparison with experiments. Using the example of some recent experiments carried out on beamline 116 at Diamond Light Source near Oxford, we discuss how such experimental results can be interpreted in view and in conjunction with numerical deformation models, particularly those incorporating dislocation effects, e.g., finite-element based pseudo-continuum strain gradient formulations, and discrete dislocation simulations. Post-processing of FE and discrete dislocation simulations is described, illustrating the kind of information that can be extracted from comparisons between modeling and experimental data. PMID

  19. Liquid metal cooling of synchrotron optics

    International Nuclear Information System (INIS)

    The installation of insertion devices at existing synchrotron facilities around the world has stimulated the development of new ways to cool the optical elements in the associated x-ray beamlines. Argonne has been a leader in the development of liquid metal cooling for high heat load x-ray optics for the next generation of synchrotron facilities. The high thermal conductivity, high volume specific heat, low kinematic viscosity, and large working temperature range make liquid metals a very efficient heat transfer fluid. A wide range of liquid metals were considered in the initial phase of this work. The most promising liquid metal cooling fluid identified to date is liquid gallium, which appears to have all the desired properties and the fewest number of undesired features of the liquid metals examined. Besides the special features of liquid metals that make them good heat transfer fluids, the very low vapor pressure over a large working temperature range make liquid gallium an ideal cooling fluid for use in a high vacuum environment. A leak of the liquid gallium into the high vacuum and even into very high vacuum areas will not result in any detectable vapor pressure and may even improve the vacuum environment as the liquid gallium combines with any water vapor or oxygen present in the system. The practical use of a liquid metal for cooling silicon crystals and other high heat load applications depends on having a convenient and efficient delivery system. The requirements for a typical cooling system for a silicon crystal used in a monochromator are pumping speeds of 2 to 5 gpm (120 cc per sec to 600 cc per sec) at pressures up to 100 psi

  20. Time-resolved spectroscopy using synchrotron radiation

    International Nuclear Information System (INIS)

    Work performed at the Stanford Synchrotron Radiation Laboratory (SSRL) is reported. The timing characteristics of the SPEAR beam (pulse width less than or equal to 0.4 nsec, pulse repetition period = 780 nsec) were exploited to determine dynamic behavior of atomic, molecular, excimeric, and photodissociative gas-phase species excited by vacuum-ultraviolet (VUV) radiation. Fast fluorescence timing measurements were done to determine excited-state lifetimes of Kr and Xe. Pressure-dependent timing studies on Xe gas at higher concentrations demonstrated some of the problems associated with previous kinetic modeling of the Xe2 system. It was found that even qualitative agreement of observed Xe2 lifetimes as a function of pressure required the assumption that the radiative lifetime was a strong function of internuclear separation. The radiative decays of chemically unstable fragments, CN* (B2Σ+) and XeF* (B2Σ+ and C2 Pi/sub 3/2//), were studied by pulsed photodissociation of stable parent compounds, ICN and XeF2. When the polarization of the CN* (B2Σ+) fragment fluorescence was measured, it was found to be non-zero and strongly dependent on excitation wavelength. This polarization is related to the symmetry of the photodissociative surface via a classical model, and the variations in the polarization with wavelength is attributed to symmetry and lifetime effects of a predissociating parent molecule. Despite the drawbacks of limited availability and low radiation flux, synchrotron radiation is definitely a useful spectroscopic tool for VUV studies of gas-phase systems

  1. European synchrotron radiation facility at Risoe

    International Nuclear Information System (INIS)

    The results of the feasibility study on a potential European Synchrotron Radiation Facility site at Risoe, Denmark, can be summarized as follows: The site is located in a geologically stable area. The ground is fairly flat, free from vibrations and earth movements, and the foundation properties are considered generally good. The study is based upon the machine concept and main geometry as presented in the ESF feasibility study of May 1979. However, the proposed site could accomodate a larger machine (e.g. 900 m of circumference) or a multi-facility centre. The site is located in the vicinity of Risoe National Laboratory, a R and D establishment with 850 employees and a well-developed technical and scientific infrastructure, which can provide support to the ESRF during the plant construction and operation. In particular the possible combination of synchrotron radiation with the existing neutron scattering facilities in DR 3 is emphasized. The site is located 35 km west of Copenhagen with easy access to the scientific, technological and industrial organizations in the metropolitan area. The regional infrastructure ensures easy and fast communication between the ESRF and locations in the host country as well as abroad. The site is located 35 minutes drive from Copenhagen International Airport and on a main communication route out of Copenhagen. The estimated time duration for the design, construction and commissioning of ESRF phase 1 - taking into account national regulatory procedures - is consistent with that of the ESF feasibility study, i.e. approx. 6 years. The estimated captal costs associated with site-specific structures are consistent with those of the ESF feasibility study, taking into account price increase between 1979 and 1981. It should be emphasized that the study is based upon technical and scientific assessments only, and does not reflect any official position or approval from appropriate authorities. (author)

  2. Mathematical modelling of digit specification by a sonic hedgehog gradient

    KAUST Repository

    Woolley, Thomas E.

    2013-11-26

    Background: The three chick wing digits represent a classical example of a pattern specified by a morphogen gradient. Here we have investigated whether a mathematical model of a Shh gradient can describe the specification of the identities of the three chick wing digits and if it can be applied to limbs with more digits. Results: We have produced a mathematical model for specification of chick wing digit identities by a Shh gradient that can be extended to the four digits of the chick leg with Shh-producing cells forming a digit. This model cannot be extended to specify the five digits of the mouse limb. Conclusions: Our data suggest that the parameters of a classical-type morphogen gradient are sufficient to specify the identities of three different digits. However, to specify more digit identities, this core mechanism has to be coupled to alternative processes, one being that in the chick leg and mouse limb, Shh-producing cells give rise to digits; another that in the mouse limb, the cellular response to the Shh gradient adapts over time so that digit specification does not depend simply on Shh concentration. Developmental Dynamics 243:290-298, 2014. © 2013 Wiley Periodicals, Inc.

  3. Characterization of Cadmium-Zinc Telluride Crystals Grown by 'Contactless' PVT Using Synchrotron White Beam Topography

    Science.gov (United States)

    Palosz, W.; Gillies, D.; Grasza, K.; Chung, H.; Raghothamachar, B.; Dudley, M.

    1997-01-01

    Crystals of Cd(1-x)Zn(x)Te grown by Physical Vapor Transport (PVT) using self-seeding 'contactless' techniques were characterized using synchrotron radiation (reflection, transmission, and Laue back-reflection X-ray topography). Crystals of low (x = 0.04) and high (up to x approx. = 0.4) ZnTe content were investigated. Twins and defects such as dislocations, precipitates, and slip bands were identified. Extensive inhomogeneous strains present in some samples were found to be generated by interaction (sticking) with the pedestal and by composition gradients in the crystals. Large (up to about 5 mm) oval strain fields were observed around some Te precipitates. Low angle grain boundaries were found only in higher ZnTe content (x greater than or equal to 0.2) samples.

  4. On gradient Ricci solitons with Symmetry

    OpenAIRE

    Petersen, Peter; Wylie, William

    2007-01-01

    We study gradient Ricci solitons with maximal symmetry. First we show that there are no non-trivial homogeneous gradient Ricci solitons. Thus the most symmetry one can expect is an isometric cohomogeneity one group action. Many examples of cohomogeneity one gradient solitons have been constructed. However, we apply the main result in our paper "Rigidity of gradient Ricci solitons" to show that there are no noncompact cohomogeneity one shrinking gradient solitons with nonnegative curvature.

  5. Variable metric conjugate gradient methods

    Energy Technology Data Exchange (ETDEWEB)

    Barth, T.; Manteuffel, T.

    1994-07-01

    1.1 Motivation. In this paper we present a framework that includes many well known iterative methods for the solution of nonsymmetric linear systems of equations, Ax = b. Section 2 begins with a brief review of the conjugate gradient method. Next, we describe a broader class of methods, known as projection methods, to which the conjugate gradient (CG) method and most conjugate gradient-like methods belong. The concept of a method having either a fixed or a variable metric is introduced. Methods that have a metric are referred to as either fixed or variable metric methods. Some relationships between projection methods and fixed (variable) metric methods are discussed. The main emphasis of the remainder of this paper is on variable metric methods. In Section 3 we show how the biconjugate gradient (BCG), and the quasi-minimal residual (QMR) methods fit into this framework as variable metric methods. By modifying the underlying Lanczos biorthogonalization process used in the implementation of BCG and QMR, we obtain other variable metric methods. These, we refer to as generalizations of BCG and QMR.

  6. Hydraulic gradients in rock aquifers

    International Nuclear Information System (INIS)

    This report deals with fractured rock as a host for deposits of hazardous waste. In this context the rock, with its fractures containing moving groundwater, is called the geological barrier. The desired properties of the geological barrier are low permeability to water, low hydraulic gradients and ability to retain matter dissolved in the water. The hydraulic gradient together with the permeability and the porosity determines the migration velocity. Mathematical modelling of the migration involves calculation of the water flow and the hydrodynamic dispersion of the contaminant. The porous medium approach can be used to calculate mean flow velocities and hydrodynamic dispersion of a large number of fractures are connected, which means that a large volume have to be considered. It is assumed that the porous medium approach can be applied, and a number of idealized examples are shown. It is assumed that the groundwater table is replenished by percolation at a constant rate. One-dimensional analytical calculations show that zero hydraulic gradients may exist at relatively large distance from the coast. Two-dimensional numerical calculations show that it may be possible to find areas with low hydraulic gradients and flow velocities within blocks surrounded by areas with high hydraulic conductivity. (au)

  7. Momentum expectation values : gradient terms

    OpenAIRE

    Plindov, G.I.; Dmitrieva, I.K.

    1984-01-01

    The lowest order inhomogeneity correction for the momentum expectation values, , is derived by means of Kirzhnits' gradient expansion technique. The use of the scaling allows a qualitative estimate of for the Coulomb many-body systems. A quantitative estimate of the inhomogeneity contribution to the expectation values, , for a neutral atom is made.

  8. The geomagnetic field gradient tensor

    DEFF Research Database (Denmark)

    Kotsiaros, Stavros; Olsen, Nils

    2012-01-01

    We develop the general mathematical basis for space magnetic gradiometry in spherical coordinates. The magnetic gradient tensor is a second rank tensor consisting of 3 × 3 = 9 spatial derivatives. Since the geomagnetic field vector B is always solenoidal (∇ · B = 0) there are only eight independent...

  9. Compositional gradients in Gramineae genes

    DEFF Research Database (Denmark)

    Wong, Gane Ka-Shu; Wang, Jun; Tao, Lin;

    2002-01-01

    In this study, we describe a property of Gramineae genes, and perhaps all monocot genes, that is not observed in eudicot genes. Along the direction of transcription, beginning at the junction of the 5'-UTR and the coding region, there are gradients in GC content, codon usage, and amino-acid usage...

  10. Advances and synergy of high pressure sciences at synchrotron sources

    International Nuclear Information System (INIS)

    Introductory overview to the special issue papers on high-pressure sciences and synchrotron radiation. High-pressure research in geosciences, materials science and condensed matter physics at synchrotron sources is experiencing growth and development through synergistic efforts around the world. A series of high-pressure science workshops were organized in 2008 to highlight these developments. One of these workshops, on 'Advances in high-pressure science using synchrotron X-rays', was held at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, USA, on 4 October 2008. This workshop was organized in honour of Drs Jingzhu Hu and Quanzhong Guo in celebration of their retirement after up to 18 years of dedicated service to the high-pressure community as beamline scientists at X17 of NSLS. Following this celebration of the often unheralded role of the beamline scientist, a special issue of the Journal of Synchrotron Radiation on Advances and Synergy of High-Pressure Sciences at Synchrotron Sources was proposed, and we were pleased to invite contributions from colleagues who participated in the workshop as well as others who are making similar efforts at synchrotron sources worldwide.

  11. MR pelvimetry - a practical alternative

    International Nuclear Information System (INIS)

    Pelvimetry remains a useful technique as part of the assessment of the term breech pregnancy where vaginal delivery is planned. MR pelvimetry is accurate, well tolerated and shows soft-tissue structures as well as bone. It avoids the potentially carcinogenic effects of ionising radiation and is thought to be completely safe for mother and fetus. A technique of MR pelvimetry is described which uses gradient-echo sequences. This quick, practical method makes minimal in roads into valuable scanning time, and may therefore be considered a potentially cost-effective alternative to conventional pelvimetry. (orig.)

  12. Thermal Gradient Behavior of TBCs Subjected to a Laser Gradient Test Rig: Simulating an Air-to-Air Combat Flight

    Science.gov (United States)

    Lima, Rogerio S.; Marple, Basil R.; Marcoux, P.

    2016-01-01

    A computer-controlled laser test rig (using a CO2 laser) offers an interesting alternative to traditional flame-based thermal gradient rigs in evaluating thermal barrier coatings (TBCs). The temperature gradient between the top and back surfaces of a TBC system can be controlled based on the laser power and a forced air back-face cooling system, enabling the temperature history of complete aircraft missions to be simulated. An air plasma spray-deposited TBC was tested and, based on experimental data available in the literature, the temperature gradients across the TBC system (ZrO2-Y2O3 YSZ top coat/CoNiCrAlY bond coat/Inconel 625 substrate) and their respective frequencies during air-to-air combat missions of fighter jets were replicated. The missions included (i) idle/taxi on the runway, (ii) take-off and climbing, (iii) cruise trajectory to rendezvous zone, (iv) air-to-air combat maneuvering, (v) cruise trajectory back to runway, and (vi) idle/taxi after landing. The results show that the TBC thermal gradient experimental data in turbine engines can be replicated in the laser gradient rig, leading to an important tool to better engineer TBCs.

  13. Synchrotron radiation XRF analysis of human hair

    International Nuclear Information System (INIS)

    The trace elements distribution along scalp hair is measured by SR excited XRF. The results of repeat scanning of a single hair and a strand of five hairs from the same person show that precision of the experiments is very well. The content change tendencies of most elements for 3 different hairs taken from the same area of one person are basically the same and a similar concentration gradient is presented. But the tendencies for different person's hair are quite different

  14. Operation of INDUS-1, India's first synchrotron radiation source

    International Nuclear Information System (INIS)

    INDUS-1 is a 450 MeV electron storage ring for the production of Synchrotron Radiation in Visible Ultra Violet (VUV) range with a critical wavelength of 61 A deg. The ring was commissioned in June 1999. Since then it is in regular operation. This Synchrotron Radiation Source (SRS) facility consists of a 20 MeV injector microtron, a 450 MeV booster synchrotron and a storage ring. In this paper operation aspects of INDUS-1 SRS facility will be presented. (author)

  15. Synchrotron radiation photoionization mass spectrometry of laser ablated species

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Ruiz, J., E-mail: j.alvarez@iqfr.csic.e [Instituto de Quimica Fisica Rocasolano, CSIC, 28006 Madrid (Spain); Casu, A. [University of Cagliari, 09042 Monserrato (Italy); Coreno, M. [CNR-IMIP, c/o Lab. Elettra Trieste, 00016 Montelibretti (Italy); Simone, M. de [CNR-INFM, Laboratorio Nazionale TASC, 34149 Trieste (Italy); Hoyos Campo, L.M.; Juarez-Reyes, A.M. [ICF-UNAM Cuernavaca (Mexico); Kivimaeki, A. [CNR-INFM, Laboratorio Nazionale TASC, 34149 Trieste (Italy); Orlando, S. [CNR-IMIP, c/o Lab. Elettra Trieste, 00016 Montelibretti (Italy); Sanz, M. [Instituto de Quimica Fisica Rocasolano, CSIC, 28006 Madrid (Spain); Spezzani, C. [Sincrotrone Trieste, 34149 Trieste (Italy); Stankiewicz, M. [Jagiellonian University, 30-059 Krakow (Poland); Trucchi, D.M. [CNR - ISC, 00016 Montelibretti (Italy)

    2010-02-15

    The present paper describes an experimental apparatus suitable to create and study free clusters by combining laser ablation and synchrotron radiation. First tests on sulfur samples, S, showed the production, through laser ablation, of neutral S{sub n} clusters (n = 1-8). These clusters were ionized using synchrotron radiation at photon energies from 160 eV to 175 eV, across the S 2p core edge. The feasibility of such combined ablation-synchrotron radiation experiments is demonstrated, opening new possibilities on the investigation of free clusters and radicals.

  16. Synchrotron radiation photoionization mass spectrometry of laser ablated species

    International Nuclear Information System (INIS)

    The present paper describes an experimental apparatus suitable to create and study free clusters by combining laser ablation and synchrotron radiation. First tests on sulfur samples, S, showed the production, through laser ablation, of neutral Sn clusters (n = 1-8). These clusters were ionized using synchrotron radiation at photon energies from 160 eV to 175 eV, across the S 2p core edge. The feasibility of such combined ablation-synchrotron radiation experiments is demonstrated, opening new possibilities on the investigation of free clusters and radicals.

  17. Longitudinal emittance control in high intensity proton synchrotrons

    International Nuclear Information System (INIS)

    Experiments of synchrotron injection using the direct fast chopped H- beam extracted from a surface-plasma-type H- ion source has been successfully achieved. The injection phase of the fast chopped beam from linac into the booster synchrotron is adjustable to the center of rf bucket by using this beam. It was obtained that the longitudinal emittance was controlled at the extraction of the booster synchrotron, and that the beam loss during the injection into main ring of the KEK-PS was reduced by this fast chopped beam. (author)

  18. Development of pulsed power modulator for induction synchrotron

    CERN Document Server

    Koseki, K

    2006-01-01

    A pulsed power modulator for the POP experiment of an induction synchrotron has been developed. Various difficulties in the development of the modulator, such as enormous power dissipation at a MOSFET, the resonant ringing in the output waveform, the isolation from the ground potential, and the incorrect action of a gate driving circuit, have been discussed and solved. The developed power modulator is installed into the existing accelerator, KEK 12GeV proton synchrotron. The POP experiment of the induction synchrotron has been successfully conducted. A single RF bunch injected from the 500 MeV booster ring was accelerated to the flat-top energy of 8 GeV.

  19. Proceedings of the workshop on LAMPF II synchrotron

    International Nuclear Information System (INIS)

    Topics covered at the workshop include: considerations for a staged approach to synchrotron construction; consideration of energy and cost for a kaon and/or antiproton factory; changing the transition energy in the main ring for the Fermilab antiproton beam; a lattice with 50% undispersed straight sections; bunch width considerations in a stretcher ring; a self-consistent longitudinal distribution; rapid-cycling tuned rf cavity for synchrotron use; considerations on a high-shunt impedance tunable RF cavity; rotating condensers; low extraction from the stretcher ring; an antiproton source for LAMPF II; synchrotron magnet circuit; power supply and ring magnet options; and notes for a kaon factory design

  20. Visualization of angiogenic vessels by synchrotron radiation microangiography

    International Nuclear Information System (INIS)

    The usefulness of synchrotron radiation microangiography for evaluating angiogenic vessels in regenerative therapy is illustrated. In a rabbit model of microvascular myocardial ischemia, angiogenic vessels in the heart were well visualized. In a rabbit model of hindlimb ischemia, vessel-regenerative therapy with fibroblast growth factor 4-gene incorporated to gelatin hydrogel well ameliorated muscle necrosis. Synchrotron radiation microangiography confirmed significant blood flow increase to adenosine administration in these treated rabbits (vascular responsiveness), but not in the control. Thus, synchrotron radiation microangiography is shown to be useful for the depiction, quantification and evaluation of angiogenic vessels in reproductive therapy. (author)

  1. 3 GeV Booster Synchrotron Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Wiedemann, Helmut

    2009-06-02

    Synchrotron light cna be produced from a relativistic particle beam circulating in a storage ring at extremely high intensity and brilliance over a large spectral region reaching from the far infrared regime to hard x-rays. The particles, either electrons or positrons, radiate as they are deflected in the fields of the storage ring bending magnets or of magnets specially optimized for the production of synchrotron light. The synchrotron light being very intense and well collimated in the forward direction has become a major tool in a large variety of research fields in physics, chemistry, material science, biology, and medicine.

  2. X-ray analysis of residual stress gradients in TiN coatings by a Laplace space approach and cross-sectional nanodiffraction: a critical comparison

    OpenAIRE

    Stefenelli, Mario; Todt, Juraj; Riedl, Angelika; Ecker, Werner; Müller, Thomas; Daniel, Rostislav; Burghammer, Manfred; Keckes, Jozef

    2013-01-01

    Novel scanning synchrotron cross-sectional nanobeam and conventional laboratory as well as synchrotron Laplace X-ray diffraction methods are used to characterize residual stresses in exemplary 11.5 µm-thick TiN coatings. Both real and Laplace space approaches reveal a homogeneous tensile stress state and a very pronounced compressive stress gradient in as-deposited and blasted coatings, respectively. The unique capabilities of the cross-sectional approach operating with a beam size of 100 nm ...

  3. Alternative Splice in Alternative Lice.

    Science.gov (United States)

    Tovar-Corona, Jaime M; Castillo-Morales, Atahualpa; Chen, Lu; Olds, Brett P; Clark, John M; Reynolds, Stuart E; Pittendrigh, Barry R; Feil, Edward J; Urrutia, Araxi O

    2015-10-01

    Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation. PMID:26169943

  4. Alternative methods for the design of jet engine control systems

    Science.gov (United States)

    Sain, M. K.; Leake, R. J.; Basso, R.; Gejji, R.; Maloney, A.; Seshadri, V.

    1976-01-01

    Various alternatives to linear quadratic design methods for jet engine control systems are discussed. The main alternatives are classified into two broad categories: nonlinear global mathematical programming methods and linear local multivariable frequency domain methods. Specific studies within these categories include model reduction, the eigenvalue locus method, the inverse Nyquist method, polynomial design, dynamic programming, and conjugate gradient approaches.

  5. Faraday Rotation Measure Gradients from a Helical Magnetic Field in 3C273

    Energy Technology Data Exchange (ETDEWEB)

    Zavala, Robert T.; /Naval Observ., Flagstaff; Taylor, G.B.; /NRAO, Socorro /KIPAC, Menlo Park

    2005-06-06

    Using high frequency (12-22 GHz) VLBA observations we confirm the existence of a Faraday rotation measure gradient of {approx}500 rad m{sup -2} mas{sup -1} transverse to the jet axis in the quasar 3C273. The gradient is seen in two epochs spaced roughly six months apart. This stable transverse rotation measure gradient is expected if a helical magnetic field wraps around the jet. The overall order to the magnetic field in the inner projected 40 parsecs is consistent with a helical field. However, we find an unexpected increase in fractional polarization along the edges of the source, contrary to expectations. This high fractional polarization rules out internal Faraday rotation, but is not readily explained by a helical field. After correcting for the rotation measure, the intrinsic magnetic field direction in the jet of 3C273 changes from parallel to nearly perpendicular to the projected jet motion at two locations. If a helical magnetic field causes the observed rotation measure gradient then the synchrotron emitting electrons must be separate from the helical field region. The presence or absence of transverse rotation measure gradients in other sources is also discussed.

  6. Faraday Rotation Measure Gradients from a Helical Magnetic Field in 3C273

    International Nuclear Information System (INIS)

    Using high frequency (12-22 GHz) VLBA observations we confirm the existence of a Faraday rotation measure gradient of ∼500 rad m-2 mas-1 transverse to the jet axis in the quasar 3C273. The gradient is seen in two epochs spaced roughly six months apart. This stable transverse rotation measure gradient is expected if a helical magnetic field wraps around the jet. The overall order to the magnetic field in the inner projected 40 parsecs is consistent with a helical field. However, we find an unexpected increase in fractional polarization along the edges of the source, contrary to expectations. This high fractional polarization rules out internal Faraday rotation, but is not readily explained by a helical field. After correcting for the rotation measure, the intrinsic magnetic field direction in the jet of 3C273 changes from parallel to nearly perpendicular to the projected jet motion at two locations. If a helical magnetic field causes the observed rotation measure gradient then the synchrotron emitting electrons must be separate from the helical field region. The presence or absence of transverse rotation measure gradients in other sources is also discussed

  7. 12th International School and Symposium on Synchrotron Radiation in Natural Sciences (ISSRNS 2014)

    Science.gov (United States)

    Kozak, Maciej; Kwiatek, Wojciech M.; Kowalski, Bogdan

    2015-12-01

    Polish Synchrotron Radiation Society (PTPS - Polskie Towarzystwo Promieniowania Synchrotronowego), founded in 1991, is one of the oldest world scientific societies gathering not only active users of synchrotron radiation, but also a large group of those interested in synchrotron techniques (http://www.synchrotron.org.pl)

  8. Synchrotron injectors based on high charge state ion sources

    International Nuclear Information System (INIS)

    The performance of any injector contemplated to replace the electrostatic tandem accelerators some time in the future should evidently match or surpass the characteristics of the tandems. It is a fortunate coincidence that the performance of the BNL tandem satisfies in most respects the requirements of the proposed collider, although originally tandems were not built with this application in mind. Requests for heavy ion beams with parameters suitable for injection into the rings of a heavy ion collider have appeared rather recently, at a stage when the high charge state ion sources, which in principle are capable of producing many ion species, have not yet reached such a level of performance. Therefore, consideration of such sources as part of a future injector replacing the tandem accelerators will have to rely on the extrapolation of results from existing models, developed for a different purpose. At the same time, present and future collider requirements for heavy ion beams should serve as a stimulus for the development of sources producing ions with adequate charge states and intensities. Injectors based on such sources may present a better alternative than the tandem accelerators because a higher charge-to-mass ratio of ions from the source results in a more efficient and less costly accelerator. In this report, two candidates for a high charge state, heavy ion source will be considered: an EBIS and an ECR. Other approaches, e.g. laser ion sources, are much further away in the development of a device to be used in a synchrotron injector. 25 refs., 7 figs., 4 tabs

  9. Activity report of Synchrotron Radiation Laboratory 2001

    International Nuclear Information System (INIS)

    After moved from Tanashi to Kashiwa Campus in the spring of 2000, the Synchrotron Radiation Laboratory (SRL) has been promoting the High-brilliance Light Source project, Super SOR project, in cooperation with the nationwide user group as well as with the users of the University of Tokyo. In May of 2001, the project has met with a dramatic progress. The Ministry of Education, Science, Sports and Culture organized the Advisory Board and started to discuss the future synchrotron radiation facilities in EUV and SX regime in Japan. Based on extensive discussion, they proposed the new facility consisting of a 1.8 GeV storage ring of 3rd generation type. The University of Tokyo approved to construct the proposed facility in the Kashiwa campus. The plan is supported not only by researchers in academic institutions but also bio- and chemical-industries. We strongly hope the plan will be realized in near future. On the other hand, SRL maintains a branch laboratory in the Photon Factory (PF) High Energy Accelerator Research Organization (KEK) at Tsukuba with a Revolver undulator, two beamlines and three experimental stations (BL-18A, 19A and 19B), which are and fully opened to the outside users. In the fiscal year of 2001, the operation time of the beamlines was more than 5000 hours and the number of the users was about 200. The main scientific interests and activities in the SRL at KEK-PF are directed to the electronic structures of new materials with new transport, magnetic and optical properties. The electronic structures of solid surfaces and interfaces are also intensively studied by photoelectron spectroscopy and photoelectron microscopy. The accelerator group of SRL is carrying out research works of the accelerator physics and developing the accelerator-related technology, many parts of which will be directly applied to the new light source project. This report contains the activities of the staff members of SRL and users of the three beamlines in FY2001. The status of

  10. Looking for an Alternative.

    Science.gov (United States)

    Kennedy, Jack

    1999-01-01

    Argues that high school newspapers might do well to create stronger ties with alternative weeklies. Discusses issues of niche marketing, alternative content, and alternative presentation. Notes that high school papers could learn a lot from alternative newspapers. (SR)

  11. ILUBCG2-11: Solution of 11-banded nonsymmetric linear equation systems by a preconditioned biconjugate gradient routine

    Science.gov (United States)

    Chen, Y.-M.; Koniges, A. E.; Anderson, D. V.

    1989-10-01

    The biconjugate gradient method (BCG) provides an attractive alternative to the usual conjugate gradient algorithms for the solution of sparse systems of linear equations with nonsymmetric and indefinite matrix operators. A preconditioned algorithm is given, whose form resembles the incomplete L-U conjugate gradient scheme (ILUCG2) previously presented. Although the BCG scheme requires the storage of two additional vectors, it converges in a significantly lesser number of iterations (often half), while the number of calculations per iteration remains essentially the same.

  12. Computational strain gradient crystal plasticity

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Kysar, Jeffrey W.

    2014-01-01

    A numerical method for viscous strain gradient crystal plasticity theory is presented, which incorporates both energetic and dissipative gradient effects. The underlying minimum principles are discussed as well as convergence properties of the proposed finite element procedure. Three problems...... of plane crystal plasticity are studied: pure shear of a single crystal between rigid platens as well as plastic deformation around cylindrical voids in hexagonal close packed and face centered cubic crystals. Effective in-plane constitutive slip parameters for plane strain deformation of specifically...... oriented face centered cubic crystals are developed in terms of the crystallographic slip parameters. The effect on geometrically necessary dislocation structures introduced by plastic deformation is investigated as a function of the ratio of void radius to plasticity length scale....

  13. Potential applications of synchrotron radiation to the treatment of cancer

    International Nuclear Information System (INIS)

    Although conventional radiotherapy remains to be one of the most useful treatments for cancer, it is not the best strategy to maximize the effects on the tumors and minimize the damage to the surrounding tissues due to its physical and biological characteristics. Synchrotron radiation (SR) with uniquely physical and biological advantages may represent an innovative approach for cancer treatment. In recent years, SR-based photon activation therapy, stereotactic synchrotron radiation therapy and micro-beam radiation treatment have been developed, and the results of in vitro and in vivo experiments are very promising. It is necessary to understand the physical and radiobiological principle of those novel strategies before the approach is applied to the clinic. In this paper, we summarize the advances of SR in terms of physical, radiobiological advantages and its potential clinical applications. With the successful operation of shanghai synchrotron radiation, good opportunities in China have been provided for investigations on the treatment of cancer with synchrotron radiation. (authors)

  14. Linac injector options for a relativistic heavy ion synchrotron

    International Nuclear Information System (INIS)

    A growing interest in medical uses for high energy heavy ion beams has led to two recent proposals to build dedicated medical heavy ion synchrotrons. Linear accelerators are generally preferred as injectors for synchrotrons, but in the case of heavy ions with relatively low charge to mass ratios, the required linacs are extremely large, and/or complex, low frequency structures. Cyclotrons were therefore initially proposed as the injectors for the medical synchrotrons. Recently a new radio-frequency quadrupole (RFQ) linac structure has been developed. Its excellent capture, beam transport and acceleration characteristics for low velocity ion beams makes it ideally suited as a heavy ion synchrotron injector either alone or in combination with a drift tube linac

  15. Open Cell Conducting Foams for High Synchrotron Radiation Beam Liners

    OpenAIRE

    Petracca, Stefania; Stabile, Arturo

    2014-01-01

    The possible use of open-cell conductive foams in high synchrotron radiation particle accelerator beam liners is considered. Available materials and modeling tools are reviewed, potential pros and cons are discussed, and preliminary conclusions are drawn.

  16. The Scale Invariant Synchrotron Jet of Flat Spectrum Radio Quasars

    Indian Academy of Sciences (India)

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

    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.

  17. Synchrotron radiation sources: general features and vacuum system

    International Nuclear Information System (INIS)

    In the last years the electron or positron storage rings, which were until 1970 only used for high energy physics experiments, begun to be built in several countries exclusively as electromagnetic radiation source (synchrotron radiation). The sources are generally made up by injector (linear accelerator or microtron), 'booster' (synchrotron), storage ring, insertions ('Wigglers' and ondulators) and light lines. The interest by these sources are due to the high intensity, large spectrum (from infrared to the X-rays), polarization and pulsed structure of the produced radiation. For the ultra-vacuum obtainement, necessary for the functioning storage rings (p=10-9 Torr), several special procedures are used. In Brazil the Synchrotron Radiation National Laboratory of the CNPq worked out a conceptual project of synchrotron radiation source, whose execution should begin by the construction of the several components prototypes. (L.C.)

  18. Grazing incidence synchrotron radiation optics: correlation of performance with metrology

    International Nuclear Information System (INIS)

    Image distortions produced by a cylinder mirror at the National Synchrotron Light Source are compared with performance predictions based on measurements of surface slope errors in the millimeter spatial period regime made with an optical surface profiler

  19. The use of slow-cycling synchrotrons in injection systems

    CERN Multimedia

    1966-01-01

    The PS improvement programme is concerned with increasing the potential of the PS for high energy physics. It involves developing the performance of the proton synchrotron itself and providing major items of experimental equipment to be used on the machine.

  20. Stability of high-brilliance synchrotron radiation sources

    International Nuclear Information System (INIS)

    This paper discusses the following topics: characteristics of synchrotron radiation sources; stability of the orbits; orbit control; nonlinear dynamic stability; and coherent stability and control. 1 ref., 5 figs., 1 tab

  1. Synchrotrons and their applications in medical imaging and therapy

    International Nuclear Information System (INIS)

    Full text: Australasia's first synchrotron is being built on the campus of Monash University near Melbourne. Is it of any relevance to the medical imaging and radiation therapy communities? The answer is an unequivocal yes. Synchrotrons overcome many of the problems with conventional X-ray sources and as a result make it possible to demonstrate extraordinary advances in both X-ray imaging and indeed in radio-therapy. Synchrotron imaging offers us a window into what is possible and the results are spectacular. Specific examples include lung images that reveal alveolar structure and computed tomography of single cells. For therapy treatments are being pioneered that seem to be effective on high grade gliomas. An overview of the status of medical applications using synchrotrons will be given and the proposed Australian medical imaging and therapy facilities will be described and some of the proposed research highlighted. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

  2. Solaris—National synchrotron radiation centre, project progress, May 2012

    International Nuclear Information System (INIS)

    The first Polish synchrotron radiation facility Solaris is being built at the Jagiellonian University in Krakow. The project was approved for construction in February 2010 using European Union structural funds. The Solaris synchrotron is based on the 1.5 GeV facility being built for the MAX IV project at Lund University in Sweden. A general description of the facility is given together with a status of its implementation. The specific Solaris solutions taken for the linear accelerator, beamlines and civil engineering infrastructure are outlined. - Highlights: • The current status and plans for the future development of the Solaris synchrotron are presented. • The layout and basic design parameters of the accelerator are shown and described. • The powerful scientific capabilities of the innovative design of the synchrotron are pointed out

  3. Rapid cycling synchrotron magnet with separate ac and dc circuit

    International Nuclear Information System (INIS)

    In present rapid cycling synchrotron magnets ac and dc currents flow in the same coil to give the desired field. The circuit reactance is made zero at dc and the operating frequency by running the magnet in series with an external parallel resonant LC current. We propose to return the ac flux in a gap next to the synchrotron. The dc coil encloses the ac magnetic circuit and thus links no ac flux. A shorted turn between the dc coil and ac flux enhances the separation of the two circuits. Several interesting developments are possible. The dc coil could be a stable superconductor to save power. The ac flux return gap could be identical with the synchrotron gap and contain a second synchrotron. This would double the output of the system. If the return flux gap were used for a booster, the ac coil power could be greatly reduced or radiation hardening of the ac coil could be simplified

  4. The National Synchrotron Light Source, Part I: Bright Idea

    International Nuclear Information System (INIS)

    The National Synchrotron Light Source (NSLS) was the first facility designed and built specifically for producing and exploiting synchrotron radiation. It was also the first facility to incorporate the Chasman-Green lattice for maximizing brightness. The NSLS was a $24-million project conceived about 1970. It was officially proposed in 1976, and its groundbreaking took place in 1978. Its construction was a key episode in Brookhaven's history, in the transition of synchrotron radiation from a novelty to a commodity, and in the transition of synchrotron-radiation scientists from parasitic to autonomous researchers. The way the machine was conceived, designed, promoted, and constructed illustrates much both about the tensions and tradeoffs faced by large scientific projects in the age of big science. In this article, the first of two parts, I cover the conception, design, and planning of the NSLS up to its groundbreaking. Part II, covering its construction, will appear in the next issue.

  5. The synchrotron beam, a new dimension for contrast media research?

    Science.gov (United States)

    Elleaume, H; Charvet, A M; Le Bas, J F

    1997-01-01

    Synchrotron sources can provide intense, collimated and tunable X-ray beams suitable for medical imaging and research, allowing the use of monochromatic X-rays for human examinations. At the European Synchrotron Radiation Facility (ESRF), a beam line dedicated to medical research is under commissioning. Two imaging programs are being developed, for coronary angiography and cerebral CT. The new monochromatic imaging systems should improve image contrast and provide better image quantification. The properties of synchrotron radiation are described, as well as the instrumentation of the medical beam line and its 2 imaging programs. The new possibilities offered by synchrotron radiation for contrast media research are discussed, the improvement on concentration measurement precision achievable is underlined. PMID:9240078

  6. Coherence Inherent in an Incoherent Synchrotron Radio Source

    Indian Academy of Sciences (India)

    Ashok K. Singal

    2011-12-01

    We show that a partial coherence due to antenna mechanism can be inherently present in any compact synchrotron source, which resolves many long-standing problems in the spectra and variability of compact extragalactic radio sources.

  7. Synchrotron speciation data for zero-valent iron nanoparticles

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data set encompasses a complete analysis of synchrotron speciation data for 5 iron nanoparticle samples (P1, P2, P3, S1, S2, and metallic iron) to include...

  8. CERN PSB Beam Tests of CNAO Synchrotron's Digital LLRF

    CERN Document Server

    Angoletta, M E; De Martinis, C; Falbo, L; Findlay, A; Foglio, R; Hunt, S; Tourres, D; Vescovi, C

    2008-01-01

    The Italian National Centre for Oncological hAdrontherapy (CNAO), in its final construction phase, uses proton and carbon ion beams to treat patients affected by solid tumours. At the heart of CNAO is a 78- meter circumference synchrotron that accelerates particles to up to 400 MeV/u. The synchrotron relies on a digital LLRF system based upon Digital Signal Processors (DSPs) and Field Programmable Gate Array (FPGA). This system implements cavity servoing and beam control capabilities, such as phase and radial loops. Beam tests of the CNAO synchrotron LLRF system were carried out at CERN's Proton Synchrotron Booster (PSB) in autumn 2007, to verify the combined DSP/FPGA architecture and the beam control capabilities. For this, a prototype version of CNAO's LLRF system was adapted to the PSB requirements. This paper outlines the prototype system layout and describes the tests carried out and their results. In particular, system architecture and beam control capabilities were successfully proven by comparison wit...

  9. The Synchrotron Boiler a Thermalizer in Seyfert Galaxies

    CERN Document Server

    Ghisellini, G; Svensson, R; Ghisellini, Gabriele; Haardt, Francesco; Svensson, Roland

    1996-01-01

    There are difficulties in understanding what keeps the plasma thermalized in compact sources, especially during rapid variations of the emitted flux. Particle-particle collisions are too inefficient in hot rarefied plasmas, and a faster process is called for. Synchrotron absorption is such a process. We show that relativistic electrons can thermalize in a few synchrotron cooling times by emitting and absorbing cyclo-synchrotron photons. The resulting equilibrium distribution is a Maxwellian at low energies, with a high energy power law tail when Compton cooling is important. Assuming that the particles emit completely self absorbed synchrotron radiation while they at the same time Compton scatter ambient UV photons, we calculate the time dependent behavior of the distribution function, and the final high energy spectra.

  10. Plans for use of synchrotron radiation from the Tristan rings

    International Nuclear Information System (INIS)

    Soon after the first success of storing electrons at PF in 1982, some preliminary experiments using synchrotron radiation were started. Since then the rumber of experiments and associated experiences using synchrotron x-radiation has grown so much taht requirements for the beam characteristics of synchrotron x-radiation are now much clearer. Following are some of the requirements: high intensity in the current energy region, higher brightness, more photons in the higher energy region, and sometimes a larger beam size. In order to meet some of these requirements the Tristan rings, the Accumulation and the Main Ring seem to be very suitable in the higher energy region so that plans for use of those rings are under way as a joint project between the Photon Factory and the users' community. The following material has been collected for discussion on the above mentioned use of synchrotron radiation. Further details will be published as proceedings of the planned meetings. (author)

  11. Sintered composite gradient tool materials

    OpenAIRE

    J. Mikuła; G. Matula; K. Gołombek; L.A. Dobrzański

    2008-01-01

    Purpose: Development of a new generation of the composite gradient tool materials with the core sintered withthe matrix obtained using the powder metallurgy of the chemical composition corresponding to the HS6-5-2 highspeedsteel reinforced with the WC and TiC type hard carbide phases with the growing portions of these phases inthe outward direction from the core to the surface.Design/methodology/approach: Powder Metallurgy, SEM, X-Ray Microanalysis.Findings: Powder metallurgy processes were u...

  12. Multilayer coating for high gradients

    CERN Document Server

    Kubo, Takayuki

    2016-01-01

    The multilayer coating for high gradients is reviewed. Not only the S-I-S structure, but also the S-S bilayer structure are also treated. This is an incomplete manuscript of an invited article which will be submitted to a journal. I have uploaded this version in order to help the understanding on my talk at the TESLA Technology Collaboration meeting at Saclay, France.

  13. Smooth Optimization with Approximate Gradient

    OpenAIRE

    d'Aspremont, Alexandre

    2005-01-01

    We show that the optimal complexity of Nesterov's smooth first-order optimization algorithm is preserved when the gradient is only computed up to a small, uniformly bounded error. In applications of this method to semidefinite programs, this means in some instances computing only a few leading eigenvalues of the current iterate instead of a full matrix exponential, which significantly reduces the method's computational cost. This also allows sparse problems to be solved efficiently using spar...

  14. Primordial vorticity and gradient expansion

    CERN Document Server

    Giovannini, Massimo

    2012-01-01

    The evolution equations of the vorticities of the electrons, ions and photons in a pre-decoupling plasma are derived, in a fully inhomogeneous geometry, by combining the general relativistic gradient expansion and the drift approximation within the Adler-Misner-Deser decomposition. The vorticity transfer between the different species is discussed in this novel framework and a set of general conservation laws, connecting the vorticities of the three-component plasma with the magnetic field intensity, is derived. After demonstrating that a source of large-scale vorticity resides in the spatial gradients of the geometry and of the electromagnetic sources, the total vorticity is estimated to lowest order in the spatial gradients and by enforcing the validity of the momentum constraint. By acknowledging the current bounds on the tensor to scalar ratio in the (minimal) tensor extension of the $\\Lambda$CDM paradigm the maximal comoving magnetic field induced by the total vorticity turns out to be, at most, of the or...

  15. Primordial vorticity and gradient expansion

    Science.gov (United States)

    Giovannini, Massimo; Rezaei, Zahra

    2012-02-01

    The evolution equations of the vorticities of the electrons, ions and photons in a pre-decoupling plasma are derived, in a fully inhomogeneous geometry, by combining the general relativistic gradient expansion and the drift approximation within the Adler-Misner-Deser decomposition. The vorticity transfer between the different species is discussed in this novel framework and a set of general conservation laws, connecting the vorticities of the three-component plasma with the magnetic field intensity, is derived. After demonstrating that a source of large-scale vorticity resides in the spatial gradients of the geometry and of the electromagnetic sources, the total vorticity is estimated to lowest order in the spatial gradients and by enforcing the validity of the momentum constraint. By acknowledging the current bounds on the tensor to scalar ratio in the (minimal) tensor extension of the ΛCDM paradigm, the maximal comoving magnetic field induced by the total vorticity turns out to be, at most, of the order of 10-37 G over the typical comoving scales ranging between 1 and 10 Mpc. While the obtained results seem to be irrelevant for seeding a reasonable galactic dynamo action, they demonstrate how the proposed fully inhomogeneous treatment can be used for the systematic scrutiny of pre-decoupling plasmas beyond the conventional perturbative expansions.

  16. Hearthfire reference concept No. 3. A rapid cycling synchrotron system

    International Nuclear Information System (INIS)

    This report describes a reference design for an accelerator system for heavy ion fusion based on a rapid cycling synchrotron and storage rings. The system irradiates one fusion target per second with 1 MJ, 100 TW (peak) pulses of 20 GeV Xe+8. The major components are a 550 MV linac, eight 60 Hz synchrotrons, four matching rings, 16 storage rings, and 24 final beam lines and lenses

  17. Recent Developments in Synchrotron Mössbauer Reflectometry

    Science.gov (United States)

    Deák, L.; Bottyán, L.; Major, M.; Nagy, D. L.; Spiering, H.; Szilágyi, E.; Tanczikó, F.

    2002-12-01

    Synchrotron Mössbauer Reflectometry (SMR), the grazing incidence nuclear resonant scattering of synchrotron radiation, can be applied to perform depth-selective phase analysis and to determine the isotopic and magnetic structure of thin films and multilayers. Principles and methodological aspects of SMR are briefly reviewed. Off-specular SMR provides information from the lateral structure of multilayers. In anti-ferromagneticly coupled systems the size of magnetic domains can be measured.

  18. Radio frequency system for the booster synchrotron and INDUS-1

    International Nuclear Information System (INIS)

    The synchrotron radiation facility at the Centre for Advanced Technology (CAT), consists of two storage rings of 450 MeV(INDUS-1) and 2.0 GeV(INDUS-2). In the first phase the storage ring INDUS-1 is being constructed along with a 20 MeV injector microtron and a 700 MeV booster synchrotron. Present paper describes the RF systems for the booster and the storage ring INDUS-1. (author). 2 refs., 1 fig., 1 tab

  19. An introduction to synchrotron radiation techniques and applications

    CERN Document Server

    Willmott, Philip

    2011-01-01

    This book introduces the reader to the basic concepts of the generation and manipulation of synchrotron light, its interaction with matter, and the application of synchrotron light in the “classical” techniques, while including some of the most modern technological developments. As much as possible, complicated mathematical derivations and formulas are avoided. A more heuristic approach is adopted, whereby the general physical reasoning behind the equations is highlighted.

  20. National Synchrotron Light Source safety-analysis report

    International Nuclear Information System (INIS)

    This document covers all of the safety issues relating to the design and operation of the storage rings and injection system of the National Synchrotron Light Source. The building systems for fire protection, access and egress are described together with air and other gaseous control or venting systems. Details of shielding against prompt bremstrahlung radiation and synchrotron radiation are described and the administrative requirements to be satisfied for operation of a beam line at the facility are given

  1. Femtosecond x-ray pulses from a synchrotron

    OpenAIRE

    Schoenlein, R. W.; Chong, H. H. W.; Glover, T. E.; Heimann, P. A.; Shank, C. V.; Zholents, A.A.; Zolotorev, M.S.

    2000-01-01

    An important frontier in ultrafast science is the application of femtosecond x-ray pulses to the study of structural dynamics in condensed matter. We show that femtosecond laser pulses can be used to generate high-brightness, tunable, femtosecond x-ray pulses from a synchrotron. Performance of existing and proposed femtosecond x-ray beamlines at the Advanced Light Source synchrotron are discussed.

  2. Studies of free and deposited clusters using synchrotron radiation

    International Nuclear Information System (INIS)

    Clusters deposited onto substrates or into rare gas matrices are being studied at present synchrotron radiation sources using absorption or secondary emission type spectroscopies. Thus the electronic and geometric structure of these systems can be determined as a function of particle size. Using the next generation synchrotron radiation sources, it will be possible to extend these studies to free beams of these particles where the results are not perturbed by substrate or matrix effects

  3. Avalanche photodiodes as large dynamic range detectors for synchrotron radiation

    International Nuclear Information System (INIS)

    We investigated silicon-based avalanche photodiodes (APDs) as X-ray detectors in terms of their linearity, maximum counting rates, and dynamic range with 8.4 keV synchrotron radiation. Measurements resulted in counting rates that extend from the APD's noise level of 10-2 Hz to saturation counting rates in excess of 108 Hz. In addition, by monitoring the APD's noise level and photon counting efficiency between synchrotron bursts, we demonstrate nine orders of magnitude dynamic range. ((orig.))

  4. Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron

    OpenAIRE

    Leone, Stephen R.

    2010-01-01

    Scientists at the Chemical Dynamics Beamline of the Advanced Light Source in Berkeley are continuously reinventing synchrotron investigations of physical chemistry and chemical physics with vacuum ultraviolet light. One of the unique aspects of a synchrotron for chemical physics research is the widely tunable vacuum ultraviolet light that permits threshold ionization of large molecules with minimal fragmentation. This provides novel opportunities to assess molecular energetics and reaction me...

  5. Theory of synchrotron radiation: II. Backreaction in ensembles of particles

    OpenAIRE

    Roberto AloisioINFN LNGS; Pasquale Blasi(INAF Arcetri)

    2002-01-01

    The standard calculations of the synchrotron emission from charged particles in magnetic fields does not apply when the energy losses of the particles are so severe that their energy is appreciably degraded during one Larmor rotation. In these conditions, the intensity and spectrum of the emitted radiation depend on the observation time $T_{obs}$: the standard result is recovered only in the limit $T_{obs}\\ll T_{loss}$, where $T_{loss}$ is the time for synchrotron losses. In...

  6. On the polarized beam acceleration in medium energy synchrotrons

    International Nuclear Information System (INIS)

    This lecture note reviews physics of spin motion in a synchrotron, spin depolarization mechanisms of spin resonances, and methods of overcoming the spin resonances during acceleration. Techniques used in accelerating polarized ions in the low/medium energy synchrotrons, such as the ZGS, the AGS, SATURNE, and the KEK PS and PS Booster are discussed. Problems related to polarized proton acceleration with snakes or partial snake are also examined

  7. Synchrotron radiation studies of supported metal catalysts

    International Nuclear Information System (INIS)

    Metallic clusters supported on refractory oxides have been used extensively for several decades in the production of chemicals and petroleum derived transportation fuels. Catalysts containing more than one metal component are of particular interest since the addition of a second metal provides a method of controlling the selectivity of the catalyst. That is, the second metal can alter the rates of competing reactions in a complex reaction sequence and thus alter the final product distribution of the reaction. In this work the reactions of cyclohexane in hydrogen over silica supported ruthenium and osmium catalysts were studied. Bimetallic catalysts represent an important class of materials that are of interest both scientifically and technologically. Despite the importance and long-standing use of supported metal catalysts, detailed information on the structure of the metal clusters has been difficult to obtain. The development of x-ray absorption spectroscopy with the increasing availability of synchrotron radiation, however, has provided a powerful and versatile tool for studying the structure of these complex systems. Using the Extended X-ray Absorption Fine Structure (EXAFS) technique, it is possible to obtain information on the local atomic structure of supported monometallic catalytic metals and their interaction with the support. In the discussion that follows the authors will focus on results that have been obtained on the structure of supported bimetallic cluster catalysts

  8. Golden Jubilee photos: The Proton Synchrotron

    CERN Multimedia

    2004-01-01

    Energy record Standing before the CERN personnel in the Main Auditorium on 25 November 1959, John Adams held not a bottle of champagne but a bottle of vodka. It had been presented to him a few months earlier during a visit to Dubna in the Soviet Union, where the world's most powerful accelerator had just been commissioned. He had been given strict instructions not to open the bottle until Dubna's energy record of 10 GeV had been broken. On 24 November, the record was smashed by CERN's brand new machine, the Proton Synchrotron, which accelerated protons at 24 GeV, over twice the energy of the Dubna machine. Before sending the empty bottle back to the Soviet Union, John Adams, who had headed the accelerator's construction, placed the recording of the signal in it as proof of the record. More than 40 years later, the PS is still going strong, delivering beams with particle densities a thousand times greater than when it first started operation. Over the years, other accelerators have grown up around it and the...

  9. Studying Magnetohydrodynamic Turbulence with Synchrotron Polarization Dispersion

    CERN Document Server

    Zhang, Jian-Fu; Lee, Hyeseung; Cho, Jungyeon

    2016-01-01

    We test a new technique of studying magnetohydrodynamic (MHD) turbulence suggested by Lazarian \\& Pogosyan, using synthetic synchrotron polarization observations. This paper focuses on a one-point statistics, which is termed the polarization frequency analysis, that is characterized by the variance of polarized emission as a function of the square of wavelengths along a single line of sight. We adopt a ratio $\\eta$ of the standard deviation of the line-of-sight turbulent magnetic field to the line-of-sight mean magnetic field to depict the level of turbulence. When this ratio is either large ($\\eta\\gg1$), which characterizes a turbulent field dominated region, or small ($\\eta\\lesssim0.2$), which characterizes a mean field dominated region, we obtain the polarization variance $\\left\\propto\\lambda^{-2}$ and $\\left\\propto\\lambda^{-2-2m}$, respectively. At small $\\eta$, i.e., the mean field dominated region, we successfully recover the turbulent spectral index by the polarization variance. We find that our si...

  10. Bremsstrahlung and synchrotron radiation from planet magnetospheres

    International Nuclear Information System (INIS)

    Bremsstrahlung and synchrotron radiation from the moving charged particles was calculated in planet magnetospheres. A program package RADIATION was developed for these calculations. The radiative intensity is projected on a far sphere. The directional dependence of the radiation during the penetration of charged particles through the polar cusp was calculated. The program package RADIATION can be also used for treating the radiation of plasma cluster penetrating through the electric double layer, MHD and compress magnetic bow shock, plasma fibers and pinches and in other important situations. Intensity of radiation was derived from advanced and retarded potentials calculated from the Maxwell set of equations. Only radiative fields are displayed (I ∼ 1/r2) and the space intensity distribution does not depend on the distance of the projection sphere. In future non-radiative fields will be treated as well. In this case the distance of the projection sphere will be important parameter. The program was written in FORTRAN CVF 6.5A. The Earth magnetosphere and ionosphere form a natural protective shield from cosmic radiation and solar wind. Various models of the magnetosphere are compared (Tsyganenko, Safrankova-Nemecek, IGRF, and others) in the end of the contribution. (author)

  11. METROLOGICAL CHALLENGES OF SYNCHROTRON RADIATION OPTICS

    International Nuclear Information System (INIS)

    Modern third generation storage rings, require state-of-the-art grazing incidence x-ray optics, in order to monochromate the Synchrotrons Radiation (SR) source photons, and focus them into the experimental stations. Slope error tolerances in the order of 0.5 microRad RMS, and surface roughness well below 5 angstrom RMS, are frequently specified for mirrors and gratings exceeding 300 mm in length. Non-contact scanning instruments were developed, in order to characterize SR optical surfaces, of spherical and aspherical shape. Among these, the Long Trace Profiler (LTP), a double pencil slope measuring interferometer, has proved to be particularly reliable, and was adopted by several SR optics metrology laboratories. The ELETTRA soft x-rays and optics metrology laboratory, has operated an LTP since 1992. We review the basic operating principles of this instrument, and some major instrumental and environmental improvements, that were developed in order to detect slope errors lower than 1 microRad RMS on optical surfaces up to one metre in length. A comparison among measurements made on the same reference flat, by different interferometers (most of them were LTPs) can give some helpful indications in order to optimize the quality of measurement

  12. METROLOGICAL CHALLENGES OF SYNCHROTRON RADIATION OPTICS.

    Energy Technology Data Exchange (ETDEWEB)

    SOSTERO,G.

    1999-05-25

    Modern third generation storage rings, require state-of-the-art grazing incidence x-ray optics, in order to monochromate the Synchrotrons Radiation (SR) source photons, and focus them into the experimental stations. Slope error tolerances in the order of 0.5 {micro}Rad RMS, and surface roughness well below 5 {angstrom} RMS, are frequently specified for mirrors and gratings exceeding 300 mm in length. Non-contact scanning instruments were developed, in order to characterize SR optical surfaces, of spherical and aspherical shape. Among these, the Long Trace Profiler (LTP), a double pencil slope measuring interferometer, has proved to be particularly reliable, and was adopted by several SR optics metrology laboratories. The ELETTRA soft x-rays and optics metrology laboratory, has operated an LTP since 1992. We review the basic operating principles of this instrument, and some major instrumental and environmental improvements, that were developed in order to detect slope errors lower than 1 {micro}Rad RMS on optical surfaces up to one metre in length. A comparison among measurements made on the same reference flat, by different interferometers (most of them were LTPs) can give some helpful indications in order to optimize the quality of measurement.

  13. Wavelength dependent experiments at EMBL synchrotron beamlines

    International Nuclear Information System (INIS)

    Full text. The optimised anomalous X-ray diffraction experiments were proved to facilitate crystal structure determination and often provide data sufficient to solve the phase problem. Two new structures, of glucosamine-6-phosphate synthase and deoxynucleotide kinase, have been recently solved in our group by the method of single isomorphous replacement with anomalous scattering (SIRAS). The phasing power of the single heavy atom derivative was significantly enhanced by using the optimal wavelength close to the absorption edge. Experiments were performed at the EMBL beamlines X31 and BW7A at DESY in Hamburg. Even in the absence of an anomalous scattered the choice of the optimal wavelength for data collection is important to compromise between the flux of synchrotron radiation, diffraction ability of a protein crystal, and absorption effects. Experiments carried out at the wiggler beamline BW7A using a frozen crystal of glucosamine-6-phosphate synthase have shown that the higher quality of data can be achieved using the wavelength of 1.5 A as compared to 1.0 A or 0.8 A provided the other conditions are similar. (author)

  14. Studying Magnetohydrodynamic Turbulence with Synchrotron Polarization Dispersion

    Science.gov (United States)

    Zhang, Jian-Fu; Lazarian, Alex; Lee, Hyeseung; Cho, Jungyeon

    2016-07-01

    We test a new technique for studying magnetohydrodynamic turbulence suggested by Lazarian & Pogosyan, using synthetic observations of synchrotron polarization. This paper focuses on a one-point statistics, which is termed polarization frequency analysis, that is characterized by the variance of polarized emission as a function of the square of the wavelength along a single line of sight. We adopt the ratio η of the standard deviation of the line-of-sight turbulent magnetic field to the line-of-sight mean magnetic field to depict the level of turbulence. When this ratio is large (η \\gg 1), which characterizes a region dominated by turbulent field, or small (η ≲ 0.2), which characterizes a region dominated by the mean field, we obtain the polarization variance \\propto {λ }-2 or \\propto {λ }-2-2m, respectively. At small η, i.e., in the region dominated by the mean field, we successfully recover the turbulent spectral index from the polarization variance. We find that our simulations agree well with the theoretical prediction of Lazarian & Pogosyan. With existing and upcoming data cubes from the Low-Frequency Array for Radio Astronomy (LOFAR) and the Square Kilometer Array (SKA), this new technique can be applied to study the magnetic turbulence in the Milky Way and other galaxies.

  15. Characterization of Medipix3 With Synchrotron Radiation

    CERN Document Server

    Gimenez, E N; Marchal, J; Turecek, D; Ballabriga, R; Tartoni, N; Campbell, M; Llopart, X; Sawhney, K J S

    2011-01-01

    Medipix3 is the latest generation of photon counting readout chips of the Medipix family. With the same dimensions as Medipix2 (256 x 256 pixels of 55 mu m x 55 mu m pitch each), Medipix3 is however implemented in an 8-layer metallization 0.13 mu m CMOS technology which leads to an increase in the functionality associated with each pixel over Medipix2. One of the new operational modes implemented in the front-end architecture is the Charge Summing Mode (CSM). This mode consists of a charge reconstruction and hit allocation algorithm which eliminates event-by-event the low energy counts produced by charge-shared events between adjacent pixels. The present work focuses on the study of the CSM mode and compares it to the Single Pixel Mode (SPM) which is the conventional readout method for these kind of detectors and it is also implemented in Medipix3. Tests of a Medipix3 chip bump-bonded to a 300 mu m thick silicon photodiode sensor were performed at the Diamond Light Source synchrotron to evaluate the performan...

  16. The RF Cycle of the PIMMS Synchrotron

    CERN Document Server

    Crescenti, M; Rossi, S

    1999-01-01

    This paper deals with the study of the rf cycle of the synchrotron of the Proton-Ion Medical Machine Study (PIMMS) hosted at CERN. The cycle comprises the adiabatic trapping, the acceleration and the rf gymnastics, both for protons and fully stripped carbon ions. The injection energy is 20 MeV for protons and 7 MeV/u for carbon. The maximum extraction energies are 250 MeV for protons and 400 MeV/u for carbon ions. The reserved time is less than 1 s, with a maximum magnetic field ramp of less than 3 T/s. The simulations show that the beam stays inside the aperture of the machine, and that there are no longitudinal losses. At the end of the cycle the beam is ready for extraction with a Dp/p of 0.4 %. The peak rf voltage is 3 kV and the frequency range is from 0.49 to 2.85 MHz.

  17. Synchrotron Radiation Studies of Environmental Materials

    Science.gov (United States)

    Olive, Daniel; Terry, Jeff

    2009-11-01

    In the case of environmental contaminants, the mobility of elements changes depending on oxidation state. Remediation techniques often focus on changing the oxidation state in order to immobilize, by forming an insoluble species, or removing by binding a soluble species to an insoluble material. In order to accomplish this immobilization one has to understand all the possible reactions that can change the oxidation state. One of the techniques that can be used to determine the oxidation state and local atomic structure of environmental contaminants under aqueous conditions is x-ray absorption spectroscopy (XAS). Synchrotron radiation was used to excite the absorption edges of As, Tc, and Pu, in order to characterize their oxidation states and structures under environmentally relevant conditions. Granular activated carbon treated with iron has shown promise for the removal of arsenic from contaminated ground water, where XAS measurements have determined that the arsenic bound to iron oxide as AsO4^3-. Pertechnetate (TcO4^-) was found to be reduced to TcO2 in a reaction with amorphous iron sulfide (FeS). Bio-reduction of plutonium has also been studied using bacteria that may be found in nuclear waste repositories resulting in an end product of Pu(III).

  18. Unveiling the Synchrotron Cosmic Web: Pilot Study

    Science.gov (United States)

    Brown, Shea; Rudnick, Lawrence; Pfrommer, Christoph; Jones, Thomas

    2011-10-01

    The overall goal of this project is to challenge our current theoretical understanding of the relativistic particle populations in the inter-galactic medium (IGM) through deep 1.4 GHz observations of 13 massive, high-redshift clusters of galaxies. Designed to compliment/extend the GMRT radio halo survey (Venturi et al. 2007), these observations will attempt to detect the peaks of the purported synchrotron cosmic-web, and place serious limits on models of CR acceleration and magnetic field amplification during large-scale structure formation. The primary goals of this survey are: 1) Confirm the bi-modal nature of the radio halo population, which favors turbulent re-acceleration of cosmic-ray electrons (CRe) during cluster mergers as the source of the diffuse radio emission; 2) Directly test hadronic secondary models which predict the presence of cosmic-ray protons (CRp) in the cores of massive X-ray clusters; 3) Search in polarization for shock structures, a potential source of CR acceleration in the IGM.

  19. Operation of the Australian Store.Synchrotron for macromolecular crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Grischa R. [Monash University, Clayton, Victoria 3800 (Australia); Aragão, David; Mudie, Nathan J.; Caradoc-Davies, Tom T. [Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia); McGowan, Sheena; Bertling, Philip J.; Groenewegen, David; Quenette, Stevan M. [Monash University, Clayton, Victoria 3800 (Australia); Bond, Charles S. [The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia (Australia); Buckle, Ashley M. [Monash University, Clayton, Victoria 3800 (Australia); Androulakis, Steve, E-mail: steve.androulakis@monash.edu [Monash Bioinformatics Platform, Monash University, Clayton, Victoria 3800 (Australia)

    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). 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.

  20. Operation of the Australian Store.Synchrotron for macromolecular crystallography

    International Nuclear Information System (INIS)

    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). 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

  1. Discussions for the shielding materials of synchrotron radiation beamline hutches

    International Nuclear Information System (INIS)

    Many synchrotron radiation facilities are now under operation such as E.S.R.F., APS, and S.P.ring-8. New facilities with intermediated stored electron energy are also under construction and designing such as D.I.A.M.O.N.D., S.O.L.E.I.L., and S.S.R.F.. At these third generation synchrotron radiation facilities, the beamline shielding as well as the bulk shield is very important for designing radiation safety because of intense and high energy synchrotron radiation beam. Some reasons employ lead shield wall for the synchrotron radiation beamlines. One is narrow space for the construction of many beamlines at the experimental hall, and the other is the necessary of many movable mechanisms at the beamlines, for examples. Some cases are required to shield high energy neutrons due to stored electron beam loss and photoneutrons due to gas Bremsstrahlung. Ordinary concrete and heavy concrete are coming up to shield material of synchrotron radiation beamline hutches. However, few discussions have been performed so far for the shielding materials of the hutches. In this presentation, therefore, we will discuss the characteristics of the shielding conditions including build up effect for the beamline hutches by using the ordinary concrete, heavy concrete, and lead for shielding materials with 3 GeV and 8 GeV class synchrotron radiation source. (author)

  2. Determination of Constant Strain Gradients of Elastically Bent Crystal Using X-ray Mirage Fringes

    Science.gov (United States)

    Jongsukswat, Sukswat; Fukamachi, Tomoe; Hirano, Kenji; Ju, Dongying; Negishi, Riichirou; Shimojo, Masayuki; Hirano, Keiichi; Kawamura, Takaaki

    2012-07-01

    Two experimental approaches are studied to determine a parameter of the strain gradient in an elastically bent crystal. In one approach, the parameter is determined by measuring the third peak of the X-ray mirage interference fringes and in the other, by measuring the region where no mirage diffraction beam reaches on the lateral surface of the crystal. Using the X-rays from synchrotron radiation, the mirage fringes have been observed in the 220 reflection of the Si crystal whose strain is controlled in cantilever bending. These two approaches both give accurate values of the parameter of the strain gradient, showing good agreement with the values calculated using elastic theory. In addition, the residual strain due to gravity is observed by measuring mirage fringes when the bending force becomes zero.

  3. Resolving mitochondrial protein complexes using non-gradient blue native polyacrylamide gel electrophoresis

    OpenAIRE

    Yan, Liang-Jun; Forster, Michael J.

    2009-01-01

    Blue native polyacrylamide gel electrophoresis (BN-PAGE) is a powerful technique for separation and proteomic analysis of high molecular weight protein complexes. It is often performed on gradient gels and is widely used for studying mitochondrial membrane complexes involved in electron transportation and oxidative phosphorylation. In this paper, we present an alternative BN-PAGE method that uses highly porous, non-gradient polyacrylamide gels for separation of rat brain mitochondrial protein...

  4. Light scattering from suspensions under external gradients

    OpenAIRE

    Bonet i Avalos, Josep; Rubí Capaceti, José Miguel; Rodríguez, R.; Pérez Madrid, Agustín

    1990-01-01

    We analyze the light-scattering spectrum of a suspension in a viscoelastic fluid under density and velocity gradients. When a density gradient is present, the dynamic structure factor exhibits universality in the sense that its expression depends only on the reduced frequency and the reduced density gradient. For a velocity gradient, however, the universality breaks down. In this last case we have found a transition point from one to three characteristic frequencies in the spectrum, which is ...

  5. STOCHASTIC GRADIENT METHODS FOR UNCONSTRAINED OPTIMIZATION

    OpenAIRE

    Nataša Krejić; Nataša Krklec Jerinkić

    2014-01-01

    This papers presents an overview of gradient based methods for minimization of noisy functions. It is assumed that the objective functions is either given with error terms of stochastic nature or given as the mathematical expectation. Such problems arise in the context of simulation based optimization. The focus of this presentation is on the gradient based Stochastic Approximation and Sample Average Approximation methods. The concept of stochastic gradient approximation of the true gradient ...

  6. Community and ecosystem responses to elevational gradients

    DEFF Research Database (Denmark)

    Sundqvist, Maja K.; Sanders, Nate; Wardle, David A.

    2013-01-01

    Community structure and ecosystem processes often vary along elevational gradients. Their responses to elevation are commonly driven by changes in temperature, and many community- and ecosystem-level variables therefore frequently respond similarly to elevation across contrasting gradients. There...... using elevational gradients for understanding community and ecosystem responses to global climate change at much larger spatial and temporal scales than is possible through conventional ecological experiments. However, future studies that integrate elevational gradient approaches with experimental...

  7. Measurement of residual stress distribution in depth direction using monochromatic synchrotron beam with multiple wavelength

    International Nuclear Information System (INIS)

    It is essential for elucidation on forming process, deforming fracture mechanism, and so on of surface layers to grasp rapid residual stress distribution at depth direction in a very thin film such as surface modified materials and so on. As X-ray stress testing method is an effective method for stress testing method on surface layer of a material, when presenting rapid stress gradient within penetrating depth of X-ray, because of its nonlinear 2θ-sin2ψ diagram, the sin2ψ method of a common X-ray stress testing method cannot be used. In this study, by using characteristics of synchrotron radiation and multiple wavelengths to test by higher ψ angle, here was proposed a method to precisely evaluate a residual stress distribution at depth direction using both wavelength and psi dependencies on X-ray penetrating depth. Concretely, it is one to measure plural relations on 2θ-sin2ψ by using X-ray with different penetrating depth to obtain a stress distribution agreeable with all of the diagrams by using optimization method. And, here was also investigated on definition of X-ray penetrating depth obscurely treated on conventional stress gradient analysis and on integral region at weighted mean stress computation within X-ray penetrating depth. (G.K.)

  8. Indentation Size Effects in Single Crystal Copper as Revealed by Synchrotron X-ray Microdiffraction

    Energy Technology Data Exchange (ETDEWEB)

    Feng, G.; Budiman, A. S.; Nix, W. D.; Tamura, N.; Patel, J. R.

    2007-11-19

    The indentation size effect (ISE) has been observed in numerous nanoindentation studies on crystalline materials; it is found that the hardness increases dramatically with decreasing indentation size - a 'smaller is stronger' phenomenon. Some have attributed the ISE to the existence of strain gradients and the geometrically necessary dislocations (GNDs). Since the GND density is directly related to the local lattice curvature, the Scanning X-ray Microdiffraction ({mu}SXRD) technique, which can quantitatively measure relative lattice rotations through the streaking of Laue diffractions, can used to study the strain gradients. The synchrotron {mu}SXRD technique we use - which was developed at the Advanced Light Source (ALS), Berkeley Lab - allows for probing the local plastic behavior of crystals with sub-micrometer resolution. Using this technique, we studied the local plasticity for indentations of different depths in a Cu single crystal. Broadening of Laue diffractions (streaking) was observed, showing local crystal lattice rotation due to the indentation-induced plastic deformation. A quantitative analysis of the streaking allows us to estimate the average GND density in the indentation plastic zones. The size dependence of the hardness, as found by nanoindentation, will be described, and its correlation to the observed lattice rotations will be discussed.

  9. On the classification of gradient Ricci solitons

    OpenAIRE

    Petersen, Peter; Wylie, William

    2007-01-01

    We show that the only complete shrinking gradient Ricci solitons with vanishing Weyl tensor are quotients of the standard ones. This gives a new proof of the Hamilton-Ivey-Perel'man classification of 3-dimensional shrinking gradient solitons. We also prove a classification for expanding gradient Ricci solitons with constant scalar curvature and suitably decaying Weyl tensor.

  10. Second order gradient ascent pulse engineering

    CERN Document Server

    de Fouquieres, P; Glaser, S J; Kuprov, Ilya

    2011-01-01

    We report some improvements to the gradient ascent pulse engineering (GRAPE) algorithm for optimal control of quantum systems. These include more accurate gradients, convergence acceleration using the BFGS quasi-Newton algorithm as well as faster control derivative calculation algorithms. In all test systems, the wall clock time and the convergence rates show a considerable improvement over the approximate gradient ascent.

  11. Acoustically-driven thread-based tuneable gradient generators.

    Science.gov (United States)

    Ramesan, Shwathy; Rezk, Amgad R; Cheng, Kai Wei; Chan, Peggy P Y; Yeo, Leslie Y

    2016-08-01

    Thread-based microfluidics offer a simple, easy to use, low-cost, disposable and biodegradable alternative to conventional microfluidic systems. While it has recently been shown that such thread networks facilitate manipulation of fluid samples including mixing, flow splitting and the formation of concentration gradients, the passive capillary transport of fluid through the thread does not allow for precise control due to the random orientation of cellulose fibres that make up the thread, nor does it permit dynamic manipulation of the flow. Here, we demonstrate the use of high frequency sound waves driven from a chip-scale device that drives rapid, precise and uniform convective transport through the thread network. In particular, we show that it is not only possible to generate a stable and continuous concentration gradient in a serial dilution and recombination network, but also one that can be dynamically tuned, which cannot be achieved solely with passive capillary transport. Additionally, we show a proof-of-concept in which such spatiotemporal gradient generation can be achieved with the entire thread network embedded in a three-dimensional hydrogel construct to more closely mimic the in vivo tissue microenvironment in microfluidic chemotaxis studies and cell culture systems, which is then employed to demonstrate the effect of such gradients on the proliferation of cells within the hydrogel. PMID:27334420

  12. On diamond windows for high power synchrotron x-ray beams

    International Nuclear Information System (INIS)

    X-ray windows are often used on the front end of synchrotron beamlines to isolate the ultra high vacuum of the storage ring from the downstream environment. The windows are usually made of low atomic number materials, such as beryllium, for maximum x-ray transmission, and they must survive and remain vacuum tight during repeated thermal cycles. The intense x-ray beams generated by the wigglers and undulators at high energy storage rings can deposit substantial amounts of localized heat in the (actively cooled) windows leading to high temperatures, and vacuum or structural failure. Thermal filters upstream of the windows can be used to reduce the radiation absorbed in the windows. This solution has limitations, however, since a small amount of filtering may still leave an unacceptable amount of heat to be absorbed in the windows, while substantial filtering will absorb a large amount of the useful photons. Recent advances in chemical vapor deposition (CVD) technology has made available thin, free-standing polycrystalline diamond films that can be used as the window material on high heat load synchrotron x-ray beamlines. Diamond windows have many advantages that stem from the exceptional thermal, structural, and physical properties of diamond. Numerical simulation indicates that diamond windows offer an attractive alternative to beryllium windows for use on the third generation x-ray synchrotron radiation beamlines. Utilization, design, and fabrication aspects of diamond windows for high heat load x-ray beamlines are discussed, and analytical results are presented to provide a basis for design and testing of such windows

  13. Sintered composite gradient tool materials

    Directory of Open Access Journals (Sweden)

    J. Mikuła

    2008-07-01

    Full Text Available Purpose: Development of a new generation of the composite gradient tool materials with the core sintered withthe matrix obtained using the powder metallurgy of the chemical composition corresponding to the HS6-5-2 highspeedsteel reinforced with the WC and TiC type hard carbide phases with the growing portions of these phases inthe outward direction from the core to the surface.Design/methodology/approach: Powder Metallurgy, SEM, X-Ray Microanalysis.Findings: Powder metallurgy processes were used to fabricate the proposed gradient materials, i.e., compacting inthe closed die and sintering. The method of sequential pouring of the successive portions of the powder mixes intothe die was used to ensure a high ductility of the fabricated material core with the HS6-5-2 steel matrix reinforcedwith the hard WC and TiC carbides phases, so that portions of powder with the high percentage of the hard carbidesphases would form the outer layers of the prepreg.Practical implications: Employment of powder metallurgy for fabricating the steel based tool materials givesthe possibility to preserve properties characteristic of the traditional cemented carbides and with the high ductilitycharacteristic of steel, yet better than the traditional sintered high-speed steels obtained with the ASP method.Originality/value: Providing of high properties characteristic of cemented carbides with the high ductilitycharacteristic of steel can be mostly because of the possibility of ensuring the gradients of the chemicalcomposition and properties, cutting simultaneously fabrication costs thanks to savings made on the hard carbidephase, used in the tool surface layer only.

  14. Multipositional internal target at the Yerevan synchrotron

    International Nuclear Information System (INIS)

    Main characteristics of the inner targets of three gamma-ray beams from the Erevan synchrotron are given. The accelerated electron beam is dumped on the targets by the orbit local disturbance method. Oscillograms of the beam stretching with time during extraction are given for different target operation. Some drawbacks of the design of the operating targets are pointed out, the main being the large period of time (about 3 hours) required to replace the target radiator. The comparative analysis of other known target designs is presented. The investigation was aimed at the development of a new target design that may ensure the possibility of an operative radiator replacement without breaking the accelerator vacuum with minimum effort and time. The problem has been solved by the modification of the present target design. An additional electromotor has been installed on the target chamber; the shaft pf the electromotor passes through the vacuum seal inside the chamber. The shaft has a gear at the end and it can be engaged with a gear at the main rod end of the target. 8 various radiators may be placed simulltaniously on the gear. The accuracy of installing each radiator in the radial direction is +-0.2 mm, and the accuracy of fixing if in rotation is +-0.3 degree. The replacement of the radiator takes not more than 3 min. The target may be used as an inner or an outer target in experiments in interactions of various materials with a particle beam. The relay control system for the multi-position target is described

  15. Nuclear dynamical diffraction using synchrotron radiation

    International Nuclear Information System (INIS)

    The scattering of synchrotron radiation by nuclei is extensively explored in this thesis. From the multipole electric field expansion resulting from time-dependent nonrelativistic perturbation theory, a dynamical scattering theory is constructed. This theory is shown, in the many particle limit, to be equivalent to the semi-classical approach where a quantum mechanical scattering amplitude is used in the Maxwell inhomogeneous wave equation. The Moessbauer specimen whose low-lying energy levels were probed is a ferromagnetic lattice of 57Fe embedded in a yttrium iron garnet (YIG) crystal matrix. The hyperfine fields in YIG thin films were studied at low and room temperature using time-resolved quantum beat spectroscopy. Nuclear hyperfine structure quantum beats were measured using a fast plastic scintillator coincidence photodetector and associated electronics having a time resolution of 2.5 nsec. The variation of the quantum beat patterns near the Bragg [0 0 2] diffraction peak gave a Lamb-Moessbauer factor of 8.2±0.4. Exploring characteristic dynamical features in the higher order YIG [0 0 10] reflection revealed that one of the YIG crystals had bifurcated into two different layers. The dynamics of nuclear superradiance was explored. This phenomenon includes the radiative speedup exhibited by a collective state of particles, and, in striking concurrence, resonance frequency shifts. A speedup of a factor of 4 in the total decay rate and a beat frequency shift of 1 1/2 natural resonance linewidths were observed. Nuclear resonance scattering was also found to be a useful way of performing angular interferometry experiments, and it was used to observe the phase shift of a rotated quantum state. On the whole, nuclear dynamical diffraction theory has superbly explained many of the fascinating features of resonant magnetic dipole radiation scattered by a lattice of nuclei

  16. 1994 activity report: Stanford Synchrotron Radiation Laboratory

    International Nuclear Information System (INIS)

    The SSRL facility delivered 89% of the scheduled user beam to 25 experimental stations during 6.5 months of user running. Users from private industry were involved in 31% of these experiments. The SPEAR accelerator ran very well with no major component failures and an unscheduled down time of only 2.9%. In addition to this increased reliability, there was a significant improvement in the stability of the beam. The enhancements to the SPEAR orbit as part of a concerted three-year program were particularly noticeable to users. The standard deviation of beam movement (both planes) in the last part of the run was 80 microns, major progress toward the ultimate goal of 50-micron stability. This was a significant improvement from the previous year when the movement was 400 microns in the horizontal and 200 microns in the vertical. A new accelerator Personal Protection System (PPS), built with full redundancy and providing protection from both radiation exposure and electrical hazards, was installed in 1994. It is not possible to describe in this summary all of the scientific experimentation which was performed during the run. However, the flavor of current research projects and the many significant accomplishments can be realized by the following highlights: A multinational collaboration performed several experiments involving x-ray scattering from nuclear resonances; Studies related to nuclear waste remediation by groups from Los Alamos National Laboratory and Pacific Northwest Laboratories continued in 1994; Diffraction data sets for a number of important protein crystals were obtained; During the past two years a collaboration consisting of groups from Hewlett Packard, Intel, Fisons Instruments and SSRL has been exploring the utility of synchrotron radiation for total reflection x-ray fluorescence (TRXRF); and High-resolution angle-resolved photoemission experiments have continued to generate exciting new results from highly correlated and magnetic materials

  17. Altitude precipitation gradient in Serbia

    Directory of Open Access Journals (Sweden)

    Živković Nenad M.

    2004-01-01

    Full Text Available Using average annual precipitations data for period 1961-90. from all rain gauges in Serbia, southern of Sava and Danube rivers, the map of altitude precipitations gradient is constructed. 59 regions homogeneous for relation X=f(H are obtained by regression analysis method (two-dimensional type, X precipitation height and H - altitude. Some new method are applied, some limitations are shown, some regularities are found in disposition of precipitation growth and it is indicated on practical application of this method in physico-geographical research.

  18. Gradient Clogging in Depth Filtration

    OpenAIRE

    Datta, S.; Redner, S.

    1998-01-01

    We investigate clogging in depth filtration, in which a dirty fluid is ``cleaned'' by the trapping of dirt particles within the pore space during flow through a porous medium. This leads to a gradient percolation process which exhibits a power law distribution for the density of trapped particles at downstream distance x from the input. To achieve a non-pathological clogging (percolation) threshold, the system length L should scale no faster than a power of ln w, where w is the width. Non-tri...

  19. Strain gradient effects on cyclic plasticity

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Legarth, Brian Nyvang

    2010-01-01

    Size effects on the cyclic shear response are studied numerically using a recent higher order strain gradient visco-plasticity theory accounting for both dissipative and energetic gradient hardening. Numerical investigations of the response under cyclic pure shear and shear of a finite slab between...... rigid platens have been carried out, using the finite element method. It is shown for elastic–perfectly plastic solids how dissipative gradient effects lead to increased yield strength, whereas energetic gradient contributions lead to increased hardening as well as a Bauschinger effect. For linearly...... hardening materials it is quantified how dissipative and energetic gradient effects promote hardening above that of conventional predictions. Usually, increased hardening is attributed to energetic gradient effects, but here it is found that also dissipative gradient effects lead to additional hardening in...

  20. Study for a proposed Phase I Energy Recovery Linac (ERL) Synchrotron Light Source at Cornell University

    International Nuclear Information System (INIS)

    Synchrotron radiation (SR) has become an essential and rapidly growing tool across the sciences and engineering. World-wide, about 70 SR sources are in various stages of operation, construction, or planning, representing a cumulative investment on many billions of dollars and serving a growing research community well in excess of 10,000 scientists. To date, all major SR x-ray facilities are based on electron (or positron) storage rings. Given the expected continued growth, importance and expense of SR sources, it is important to ask if there are alternatives to the storage ring SR source which offer advantages of capability or cost. A step in this direction is being taken by the SR community with the proposed developments of linac-based x-ray free-electron lasers (XFELs) utilizing the self-amplified spontaneous emission process (SASE). However, the versatility of modern developments in accelerator physics, as applied to synchrotron radiation, is not limited to storage rings or XFELs. New developments in laser driven photoinjectors and superconducting linac technology open new and exciting possibilities for novel SR-generating machines which offer extraordinary capabilities and promise to catalyze whole new areas of SR-based science

  1. Application of X-rays and Synchrotron X Rays to Residual Stress Evaluation Near Surfaces

    International Nuclear Information System (INIS)

    A nondestructive residual stress analysis can be performed using diffraction methods. The easiest accessible radiation is characteristic X radiation that has a penetration depth of ∼10 microm suitable for the determination of the residual stresses in near-surface layers. Special techniques have been developed, e.g., with respect to in situ analyses of the stress state in oxide layers and the residual stress analysis in coarse grained zones of steel welds or annealed Ni-base alloys. Depending on the size of the gauge volume, neutron diffraction can provide information at depths of tens of millimetres of steel and many tens of millimetres of Al. An alternative to the use of the characteristic synchrotron radiation is the use of a high-energy polychromatic beam in an energy dispersive arrangement, which gives access to higher penetration depths at still gauge volumes as small as 100 microm x 100 microm x 1 mm in steel rods of 15-mm diameter. The combination of neutrons with conventional X rays and monochromatic and polychromatic synchrotron radiation allows for a comprehensive investigation of the phase composition, the texture, and the residual stresses

  2. Progress in multi-element silicon detectors for synchrotron XRF applications

    International Nuclear Information System (INIS)

    Multi-element silicon strip detectors, in conjunction with integrated circuit pulse-processing electronics, offer an attractive alternative to conventional lithium-drifted silicon and high purity germanium detectors for high count rate, low noise synchrotron x-ray fluorescence applications. We have been developing these types of detectors specifically for low noise synchrotron applications, such as extended x-ray absorption fine structure spectroscopy, microprobe x-ray fluorescence and total reflection x-ray fluorescence. The current version of the 192-element detector and integrated circuit preamplifier, cooled to -25 degrees C with a single-stage thermoelectric cooler, achieves an energy resolution of <200 eV full width of half maximum (FWHM) per channel (at 5.9 keV, 2 μs peaking time), and each detector element is designed to handle ∼20 kHz count rate. The detector system will soon be completed to 64 channels using new application specific integrated circuit (ASIC) amplifier chips, new CAMAC (Computer Automated Measurement and Control standard) analog-to-digital converters recently developed at Lawrence Berkeley National Laboratory (LBNL), CAMAC histogramming modules, and Macintosh-based data acquisition software. We report on the characteristics of this detector system, and the work in progress towards the next generation system

  3. Synchrotron radiation X-ray tomographic microscopy (SRXTM of brachiopod shell interiors for taxonomy: Preliminary report

    Directory of Open Access Journals (Sweden)

    Motchurova-Dekova Neda

    2010-01-01

    Full Text Available Synchrotron radiation X-ray tomographic microscopy (SRXTM is a non-destructive technique for the investigation and visualization of the internal features of solid opaque objects, which allows reconstruction of a complete three-dimensional image of internal structures by recording of the differences in the effects on the passage of waves of energy reacting with those structures. Contrary to X-rays, produced in a conventional X-ray tube, the intense synchrotron light beams are sharply focused like a laser beam. We report encouraging results from the use of SRXTM for purely taxonomic purposes in brachiopods: an attempt to find a non-destructive and more efficient alternative to serial sectioning and several other methods of dissection together with the non-destructive method of X-ray computerised micro-tomography. Two brachiopod samples were investigated using SRXTM. In “Rhynchonella” flustracea it was possible to visualise the 3D shape of the crura and dental plates. In Terebratulina imbricata it was possible to reveal the form of the brachidium. It is encouraging that we have obtained such promising results using SRXTM with our very first two fortuitous samples, which had respectively fine-grained limestone and marl as infilling sediment, in contrast to the discouraging results communicated to us by some colleagues who have tested specimens with such infillings using X-ray micro-tomography. In future the holotypes, rare museum specimens or delicate Recent material may be preferentially subjected to this mode of analysis.

  4. Gap-tapered undulators for high-photon-energy synchrotron radiation production

    International Nuclear Information System (INIS)

    Narrow-gap, short-period undulators are of interest to maximize the achievable photon energy at lower-energy storage rings. An important consideration is matching the e-beam beta function in the straight section to the vertical aperture at the insertion device so as to maximize vertical acceptance, beam lifetime, and injection efficiency. Various approaches have been considered such as in-vacuum undulators, undulators with flexible vacuum chambers, and superconducting undulators. In each of these the undulator gap is constant along the undulator length, in which case the optimum beta function is equal to one-half the length. We discuss an alternate approach in which the undulator gap is tapered to follow the transverse profile of the e-beam envelope. This allows the use of a relatively long undulator within a low-beta straight section. The undulator gap is physically and magnetically matched to the e-beam envelope throughout the straight section. The undulator period is varied to maintain constant photon resonance while everywhere maximizing the magnetic field strength. This approach optimizes the high-photon-energy synchrotron radiation generation. The achievable synchrotron radiation spectral properties and tunability of such a device are examined

  5. Industrial Use of Synchrotron Radiation:. Love at Second Sight

    Science.gov (United States)

    Hormes, Josef; Warner, Jeffrey

    2012-06-01

    Synchrotron radiation (SR) has become one of the most valuable tools for many areas of basic and applied research. In some cases, techniques have been developed that rely completely on the specific properties of synchrotron radiation; in many other cases, using synchrotron radiation has opened completely new and exciting opportunities for conventional techniques. In this chapter, the challenges, problems, and advantages of the industrial use of synchrotron radiation will be highlighted, in an admittedly subjective way, based on the experience of the authors at various synchrotron radiation facilities. "Typical" examples of industrial use of SR will be discussed for all areas of industrial activities, i.e., production, quality control and control of regulatory requirements, and research and development. Emphasis will be put on examples from R&D as this is the most intensively used area. Because this field is much too broad for a complete review here, examples will focus on applications from just three major sectors: biotechnology, pharmaceuticals and cosmetics, and automotive and mining. Environmental research is a fourth area that will be partly covered in the section on regulatory requirements.

  6. Vacuum chambers full of ideas for the Swedish synchrotron

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    CERN’s Vacuum, Surfaces and Coatings group has contributed to the development of vacuum chambers for the MAX IV synchrotron, which has just been officially opened in Sweden.   A section of the new 3 GeV MAX IV synchrotron at the time of installation. In the centre of the magnets you can see the vacuum chamber developed in collaboration with CERN. (Photo: Marek Grabski, MAX IV Vacuum group) On 21 June, the King and the Prime Minister of Sweden officially opened MAX IV, a brand-new synchrotron in Lund, Sweden. The summer solstice, the longest day of the year, was deliberately chosen for the ceremony: MAX IV, a cutting-edge synchrotron, will deliver the brightest X-rays ever produced to more than 2000 users. Some 1500 kilometres away, a team at CERN followed the opening ceremony with a touch of pride. The Vacuum, Surfaces and Coatings group in the Technology department (TE-VSC) participated in the construction of this new synchrotron. Its contribution lies at the very hea...

  7. Applications of synchrotron radiation to Chemical Engineering Science: Workshop report

    International Nuclear Information System (INIS)

    This report contains extended abstracts that summarize presentations made at the Workshop on Applications of Synchrotron Radiation to Chemical Engineering Science held at Argonne National Laboratory (ANL), Argonne, IL, on April 22--23, 1991. The talks emphasized the application of techniques involving absorption fluorescence, diffraction, and reflection of synchrotron x-rays, with a focus on problems in applied chemistry and chemical engineering, as well as on the use of x-rays in topographic, tomographic, and lithographic procedures. The attendees at the workshop included experts in the field of synchrotron science, scientists and engineers from ANL, other national laboratories, industry, and universities; and graduate and undergraduate students who were enrolled in ANL educational programs at the time of the workshop. Talks in the Plenary and Overview Session described the status of and special capabilities to be offered by the Advanced Photon Source (APS), as well as strategies and opportunities for utilization of synchrotron radiation to solve science and engineering problems. Invited talks given in subsequent sessions covered the use of intense infrared, ultraviolet, and x-ray photon beams (as provided by synchrotrons) in traditional and nontraditional areas of chemical engineering research related to electrochemical and corrosion science, catalyst development and characterization, lithography and imaging techniques, and microanalysis

  8. Review of third and next generation synchrotron light sources

    International Nuclear Information System (INIS)

    Synchrotron radiation (SR) is having a very large impact on interdisciplinary science and has been tremendously successful with the arrival of third generation synchrotron x-ray sources. But the revolution in x-ray science is still gaining momentum. Even though new storage rings are currently under construction, even more advanced rings are under design (PETRA III and the ultra high energy x-ray source) and the uses of linacs (energy recovery linac, x-ray free electron laser) can take us further into the future, to provide the unique synchrotron light that is so highly prized for today's studies in science in such fields as materials science, physics, chemistry and biology, for example. All these machines are highly reliant upon the consequences of Einstein's special theory of relativity. The consequences of relativity account for the small opening angle of synchrotron radiation in the forward direction and the increasing mass an electron gains as it is accelerated to high energy. These are familiar results to every synchrotron scientist. In this paper we outline not only the origins of SR but discuss how Einstein's strong character and his intuition and excellence have not only marked the physics of the 20th century but provide the foundation for continuing accelerator developments into the 21st century

  9. Applications of synchrotron radiation to Chemical Engineering Science: Workshop report

    Energy Technology Data Exchange (ETDEWEB)

    1991-07-01

    This report contains extended abstracts that summarize presentations made at the Workshop on Applications of Synchrotron Radiation to Chemical Engineering Science held at Argonne National Laboratory (ANL), Argonne, IL, on April 22--23, 1991. The talks emphasized the application of techniques involving absorption fluorescence, diffraction, and reflection of synchrotron x-rays, with a focus on problems in applied chemistry and chemical engineering, as well as on the use of x-rays in topographic, tomographic, and lithographic procedures. The attendees at the workshop included experts in the field of synchrotron science, scientists and engineers from ANL, other national laboratories, industry, and universities; and graduate and undergraduate students who were enrolled in ANL educational programs at the time of the workshop. Talks in the Plenary and Overview Session described the status of and special capabilities to be offered by the Advanced Photon Source (APS), as well as strategies and opportunities for utilization of synchrotron radiation to solve science and engineering problems. Invited talks given in subsequent sessions covered the use of intense infrared, ultraviolet, and x-ray photon beams (as provided by synchrotrons) in traditional and nontraditional areas of chemical engineering research related to electrochemical and corrosion science, catalyst development and characterization, lithography and imaging techniques, and microanalysis.

  10. The pressure behaviour of actinides via synchrotron radiation

    International Nuclear Information System (INIS)

    Various aspects of performing high-pressure studies with radioactive f-elements using synchrotrons as sources of X-rays are discussed. For ultra-high pressures, intense well-focused beams of 10 to 30 microns in diameter and a single wavelength of 0.3 to 0.7 angstrom are desired for angle dispersive diffraction measurements. Special considerations are necessary for the studies of transuranium elements under pressure at synchrotron facilities. Normally, with these actinides the pressure cells are prepared off-site and shipped to the synchrotron for study. Approved containment techniques must be provided to assure there is not a potential for the release of sample material. The goal of these high-pressure studies is to explore the fundamental science occurring as pressure is applied to the actinide samples. One of the primary effects of pressure is to reduce interatomic distances, and the goal is to ascertain the changes in bonding and electronic nature of the system that result as atoms and electronic orbitals are forced closer together. Concepts of the science being pursued with these f-elements are outlined. A brief discussion of the behaviour of americium metal under pressure performed recently at the ESRF is provided as an example of the high-pressure research being performed with synchrotron radiation. Also discussed here is the important role synchrotrons play and the techniques/procedures employed in high-pressure studies with actinides. (authors)

  11. Synchrotron radiation - a perfect mimic of star light

    International Nuclear Information System (INIS)

    Synchrotrons are an ideal solar mimic (or more generally a mimic of star light). Continuously tuneable from the IR to the VUV (and beyond into the X ray region) they produce light beams with intensities compatible with sunlight, not the multiphoton processes induced by lasers, and therefore have become a standard tool in environmental studies. In this talk I will review how synchrotron facilities have been used to study the photochemical processes in the Earth's stratosphere that lead to ozone formation, and its destruction by CFCs and other anthropogenic pollutant sources and how by exploring the VUV-vis spectroscopy the role of chemical species in both ozone depletion and global warming is being evaluated and used to suggest new more environmental friendly chemical for industry. Synchrotrons may also be used to study the biological effects of environmental change for example by exploring the effect of enhanced UV levels due to loss of stratospheric ozone (the so called ozone hole). Synchrotron radiation may be used to explore the effects of enhanced UV levels of plants and the mechanisms leading to skin cancers, the latter by studying DNA damage. In this talk I will discuss recent experiments using synchrotron radiation to explore DNA damage and what such experiments tell us about mechanisms involved

  12. Modelisation of synchrotron radiation losses in realistic tokamak plasmas

    International Nuclear Information System (INIS)

    Synchrotron radiation losses become significant in the power balance of high-temperature plasmas envisaged for next step tokamaks. Due to the complexity of the exact calculation, these losses are usually roughly estimated with expressions derived from a plasma description using simplifying assumptions on the geometry, radiation absorption, and density and temperature profiles. In the present article, the complete formulation of the transport of synchrotron radiation is performed for realistic conditions of toroidal plasma geometry with elongated cross-section, using an exact method for the calculation of the absorption coefficient, and for arbitrary shapes of density and temperature profiles. The effects of toroidicity and temperature profile on synchrotron radiation losses are analyzed in detail. In particular, when the electron temperature profile is almost flat in the plasma center, as for example in ITB confinement regimes, synchrotron losses are found to be much stronger than in the case where the profile is represented by its best generalized parabolic approximation, though both cases give approximately the same thermal energy contents. Such an effect is not included in present approximate expressions. Finally, we propose a seven-variable fit for the fast calculation of synchrotron radiation losses. This fit is derived from a large database, which has been generated using a code implementing the complete formulation and optimized for massively parallel computing. (author)

  13. Mineral density volume gradients in normal and diseased human tissues.

    Directory of Open Access Journals (Sweden)

    Sabra I Djomehri

    Full Text Available Clinical computed tomography provides a single mineral density (MD value for heterogeneous calcified tissues containing early and late stage pathologic formations. The novel aspect of this study is that, it extends current quantitative methods of mapping mineral density gradients to three dimensions, discretizes early and late mineralized stages, identifies elemental distribution in discretized volumes, and correlates measured MD with respective calcium (Ca to phosphorus (P and Ca to zinc (Zn elemental ratios. To accomplish this, MD variations identified using polychromatic radiation from a high resolution micro-computed tomography (micro-CT benchtop unit were correlated with elemental mapping obtained from a microprobe X-ray fluorescence (XRF using synchrotron monochromatic radiation. Digital segmentation of tomograms from normal and diseased tissues (N=5 per group; 40-60 year old males contained significant mineral density variations (enamel: 2820-3095 mg/cc, bone: 570-1415 mg/cc, cementum: 1240-1340 mg/cc, dentin: 1480-1590 mg/cc, cementum affected by periodontitis: 1100-1220 mg/cc, hypomineralized carious dentin: 345-1450 mg/cc, hypermineralized carious dentin: 1815-2740 mg/cc, and dental calculus: 1290-1770 mg/cc. A plausible linear correlation between segmented MD volumes and elemental ratios within these volumes was established, and Ca/P ratios for dentin (1.49, hypomineralized dentin (0.32-0.46, cementum (1.51, and bone (1.68 were observed. Furthermore, varying Ca/Zn ratios were distinguished in adapted compared to normal tissues, such as in bone (855-2765 and in cementum (595-990, highlighting Zn as an influential element in prompting observed adaptive properties. Hence, results provide insights on mineral density gradients with elemental concentrations and elemental footprints that in turn could aid in elucidating mechanistic processes for pathologic formations.

  14. Mineral density volume gradients in normal and diseased human tissues.

    Science.gov (United States)

    Djomehri, Sabra I; Candell, Susan; Case, Thomas; Browning, Alyssa; Marshall, Grayson W; Yun, Wenbing; Lau, S H; Webb, Samuel; Ho, Sunita P

    2015-01-01

    Clinical computed tomography provides a single mineral density (MD) value for heterogeneous calcified tissues containing early and late stage pathologic formations. The novel aspect of this study is that, it extends current quantitative methods of mapping mineral density gradients to three dimensions, discretizes early and late mineralized stages, identifies elemental distribution in discretized volumes, and correlates measured MD with respective calcium (Ca) to phosphorus (P) and Ca to zinc (Zn) elemental ratios. To accomplish this, MD variations identified using polychromatic radiation from a high resolution micro-computed tomography (micro-CT) benchtop unit were correlated with elemental mapping obtained from a microprobe X-ray fluorescence (XRF) using synchrotron monochromatic radiation. Digital segmentation of tomograms from normal and diseased tissues (N=5 per group; 40-60 year old males) contained significant mineral density variations (enamel: 2820-3095 mg/cc, bone: 570-1415 mg/cc, cementum: 1240-1340 mg/cc, dentin: 1480-1590 mg/cc, cementum affected by periodontitis: 1100-1220 mg/cc, hypomineralized carious dentin: 345-1450 mg/cc, hypermineralized carious dentin: 1815-2740 mg/cc, and dental calculus: 1290-1770 mg/cc). A plausible linear correlation between segmented MD volumes and elemental ratios within these volumes was established, and Ca/P ratios for dentin (1.49), hypomineralized dentin (0.32-0.46), cementum (1.51), and bone (1.68) were observed. Furthermore, varying Ca/Zn ratios were distinguished in adapted compared to normal tissues, such as in bone (855-2765) and in cementum (595-990), highlighting Zn as an influential element in prompting observed adaptive properties. Hence, results provide insights on mineral density gradients with elemental concentrations and elemental footprints that in turn could aid in elucidating mechanistic processes for pathologic formations. PMID:25856386

  15. National Synchrotron Light Source 2008 Activity Report

    International Nuclear Information System (INIS)

    Funded by the U.S. Department of Energy's Office of Basic Energy Sciences, the National Synchrotron Light Source (NSLS) is a national user facility that operates two electron storage rings: X-Ray (2.8 GeV, 300 mA) and Vacuum Ultraviolet (VUV) (800 mev, 1.0A). These two rings provide intense light spanning the electromagnetic spectrum -- from very long infrared rays to ultraviolet light and super-short x-rays -- to analyze very small or highly dilute samples. The properties of this light, and the specially designed experimental stations, called beamlines, allow scientists in many diverse disciplines of research to perform experiments not possible at their own laboratories. Each year, about 2,200 scientists from more than 400 universities and companies use the NSLS for research in such diverse fields as biology, physics, chemistry, geology, medicine, and environmental and materials sciences. For example, researchers have used the NSLS to examine the minute details of computer chips, decipher the structures of viruses, probe the density of bone, determine the chemical composition of moon rocks, and reveal countless other mysteries of science. The facility has 65 operating beamlines, with 51 beamlines on the X-Ray Ring and 14 beamlines on the VUV-Infrared Ring. It runs seven days a week, 24 hours a day throughout the year, except during periods of maintenance and studies. Researchers are not charged for beam time, provided that the research results are published in open literature. Proprietary research is conducted on a full-cost-recovery basis. With close to 1,000 publications per year, the NSLS is one of the most prolific scientific facilities in the world. Among the many accolades given to its users and staff, the NSLS has won nine R and D 100 Awards for innovations ranging from a closed orbit feedback system to the first device able to focus a large spread of high-energy x-rays. In addition, a visiting NSLS researcher shared the 2003 Nobel Prize in Chemistry for

  16. National Synchrotron Light Source 2008 Activity Report

    Energy Technology Data Exchange (ETDEWEB)

    Nasta,K.

    2009-05-01

    Funded by the U.S. Department of Energy's Office of Basic Energy Sciences, the National Synchrotron Light Source (NSLS) is a national user facility that operates two electron storage rings: X-Ray (2.8 GeV, 300 mA) and Vacuum Ultraviolet (VUV) (800 mev, 1.0A). These two rings provide intense light spanning the electromagnetic spectrum -- from very long infrared rays to ultraviolet light and super-short x-rays -- to analyze very small or highly dilute samples. The properties of this light, and the specially designed experimental stations, called beamlines, allow scientists in many diverse disciplines of research to perform experiments not possible at their own laboratories. Each year, about 2,200 scientists from more than 400 universities and companies use the NSLS for research in such diverse fields as biology, physics, chemistry, geology, medicine, and environmental and materials sciences. For example, researchers have used the NSLS to examine the minute details of computer chips, decipher the structures of viruses, probe the density of bone, determine the chemical composition of moon rocks, and reveal countless other mysteries of science. The facility has 65 operating beamlines, with 51 beamlines on the X-Ray Ring and 14 beamlines on the VUV-Infrared Ring. It runs seven days a week, 24 hours a day throughout the year, except during periods of maintenance and studies. Researchers are not charged for beam time, provided that the research results are published in open literature. Proprietary research is conducted on a full-cost-recovery basis. With close to 1,000 publications per year, the NSLS is one of the most prolific scientific facilities in the world. Among the many accolades given to its users and staff, the NSLS has won nine R&D 100 Awards for innovations ranging from a closed orbit feedback system to the first device able to focus a large spread of high-energy x-rays. In addition, a visiting NSLS researcher shared the 2003 Nobel Prize in Chemistry for

  17. Inexact alternating direction multiplier methods for separable convex optimization

    OpenAIRE

    Hager, William W.; Zhang, Hongchao

    2016-01-01

    Inexact alternating direction multiplier methods (ADMMs) are developed for solving general separable convex optimization problems with a linear constraint and with an objective that is the sum of smooth and nonsmooth terms. The approach involves linearized subproblems, a back substitution step, and either gradient or accelerated gradient techniques. Global convergence is established. The methods are particularly useful when the ADMM subproblems do not have closed form solution or when the sol...

  18. DEVELOPMENTS IN SYNCHROTRON X-RAY COMPUTED MICROTOMOGRAPHY AT THE NATIONAL SYNCHROTRON LIGHT SOURCE.

    Energy Technology Data Exchange (ETDEWEB)

    DOWD,B.A.

    1999-07-23

    Last year, the X27A beamline at the National Synchrotron Light Source (NSLS) became dedicated solely to X-Ray Computed Microtomography (XCMT). This is a third-generation instrument capable of producing tomographic volumes of 1-2 micron resolution over a 2-3mm field of view. Recent enhancements will be discussed. These have focused on two issues: the desire for real-time data acquisition and processing and the need for highly monochromatic beam (.1 % energy bandpass). The latter will permit k-edge subtraction studies and will provide improved image contrast from below the Cr (6 keV) up to the Cs (36 keV) k-edge. A range of applications that benefit from these improvements will be discussed as well. These two goals are somewhat counterproductive, however; higher monochromaticity yields a lower flux forcing longer data acquisition times. To balance the two, a more efficient scintillator for X-ray conversion is being developed. Some testing of a prototype scintillator has been performed; preliminary results will be presented here. In the meantime, data reconstruction times have been reduced, and the entire tomographic acquisition, reconstruction and volume rendering process streamlined to make efficient use of synchrotron beam time. A Fast Filtered Back Transform (FFBT) reconstruction program recently developed helped to reduce the time to reconstruct a volume of 150 x 150 x 250 pixels{sup 3} (over 5 million voxels) from the raw camera data to 1.5 minutes on a dual R10,000 CPU. With these improvements, one can now obtain a ''quick look'' of a small tomographic volume ({approximately}10{sup 6}voxels) in just over 15 minutes from the start of data acquisition.

  19. Prospects for very-high-gradient linac-colliders

    International Nuclear Information System (INIS)

    The energy realistically attainable by an electron-positron storage ring is limited by the RF voltage and power requirements imposed by synchrotron radiation to about 100 GeV. To reach energies of 300 x 300 GeV and higher in a colliding beam machine of reasonable dimensions, we must look to the linac-collider operating at an energy gradient on the order of 100 MV/m. Proper choice of an RF structure or such a collider can minimize the total RF power requirement and the effects of longitudinal and transverse single-bunch beam loading. For an operating frequency in the range 4 to 6 GHz, the total RF power requirement for a 300 x 300 GeV collider with a luminosity of 1032 cm-2s-1 accelerating 1011 particles per bunch is on the order of 50 MW. To drive this collider, RF power sources are needed having a peak output power in the range 1-2 GW. Possibilities for attaining these peak power levels by direct generation and by energy storage and fast switching are discussed

  20. Strength gradient enhances fatigue resistance of steels

    Science.gov (United States)

    Ma, Zhiwei; Liu, Jiabin; Wang, Gang; Wang, Hongtao; Wei, Yujie; Gao, Huajian

    2016-02-01

    Steels are heavily used in infrastructure and the transportation industry, and enhancing their fatigue resistance is a major challenge in materials engineering. In this study, by introducing a gradient microstructure into 304 austenitic steel, which is one of the most widely used types of stainless steel, we show that a strength gradient substantially enhances the fatigue life of the material. Pre-notched samples with negative strength gradients in front of the notch’s tip endure many more fatigue cycles than do samples with positive strength gradients during the crack initiation stage, and samples with either type of gradient perform better than do gradient-free samples with the same average yield strength. However, as a crack grows, samples with positive strength gradients exhibit better resistance to fatigue crack propagation than do samples with negative gradients or no gradient. This study demonstrates a simple and promising strategy for using gradient structures to enhance the fatigue resistance of materials and complements related studies of strength and ductility.

  1. The Discrete Nature of the Coherent Synchrotron Radiation

    Science.gov (United States)

    Tammaro, Stefano; Pirali, Olivier; Roy, P.; Lampin, Jean François; Ducourneau, Gaël; Cuisset, Arnaud; Hindle, Francis; Mouret, Gaël

    2015-06-01

    Frequency Combs (FC) have radically changed the landscape of frequency metrology and high-resolution spectroscopy investigations extending tremendously the achievable resolution while increasing signal to noise ratio. Initially developed in the visible and near-IR spectral regions, the use of FC has been expanded to mid-IR, extreme ultra-violet and X-ray. Significant effort is presently dedicated to the generation of FC at THz frequencies. One solution based on converting a stabilized optical frequency comb using a photoconductive terahertz emitter, remains hampered by the low available THz power. Another approach is based on active mode locked THz quantum-cascade-lasers providing intense FC over a relatively limited spectral extension. Alternatively, we show that dense powerful THz FC is generated over one decade of frequency by coherent synchrotron radiation (CSR). In this mode, the entire ring behaves in a similar fashion to a THz resonator wherein electron bunches emit powerful THz pulses quasi-synchronously. The observed FC has been fully characterized and is demonstrated to be offset free. Based on these recorded specifications and a complete review of existing THz frequency comb, a special attention will be paid onto similarities and differences between them. Udem, Th., Holzwarth, H., Hänsch, T. W., Optical frequency metrology. Nature 416, 233-237 (2002) Schliesser, A., Picqué, N., Hänsch, T. W., Mid-infrared frequency combs. Nature Photon. 6, 440 (2012) Zinkstok, R. Th., Witte, S., Ubachs, W., Hogervorst, W., Eikema, K. S. E., Frequency comb laser spectroscopy in the vacuum-ultraviolet region. Physical Review A 73, 061801 (2006) Cavaletto, S. M. et al. Broadband high-resolution X-ray frequency combs. Nature Photon. 8, 520-523 (2014) Tani, M., Matsuura, S., Sakai, K., Nakashima, S. I., Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs. Applied Optics 36, 7853-7859 (1997) Burghoff, D. et al

  2. Possible applications of synchrotron radiation for materials science

    International Nuclear Information System (INIS)

    In the past 20 years, synchrotron radiation has become an important aid for solid-state physicists, chemists and biologists. On the other hand, the use of synchrotron radiation for experimental studies of a large series of specimens is still in the preliminary stage, however, is necessary for the analyzation of materials. In this paper, present and future possible applications of synchrotron radiation for the characterization of advanced materials are discussed. Beside the further optimization of techniques for the analysis of the atomic structure (e.g. diffraction, absorption spectroscopy), essential progress has to be expected in the field of nondestructive, threedimensional characterization of the microstructure of metallic and ceramic materials, especially during the synthesis of materials. (orig.)

  3. High-temperature diffraction gratings for synchrotron radiation

    International Nuclear Information System (INIS)

    SiC-based mechanically ruled master gratings and replicas are developed for synchrotron radiation instruments. An SiC-based gold replica grating without any thermal deformation due to active cooling is used in a high-photon-flux-soft x-ray monochromator that is installed in a bending magnet beamline. An SiC-based gold master grating is used in a vacuum ultraviolet/soft x-ray monochromator installed in an undulator beamline with slight groove shape deformation. This deformation is caused by the thermal change of the gold film occurring at higher than 250--300 degree C. A method for cleaning carbon-contaminated synchrotron radiation optics is tested. The ultraviolet ozone ashing method effectively cleans carbon contamination on the optics and is useful for extending the lifetime of synchrotron radiation optics

  4. Phase contrast image guidance for synchrotron microbeam radiotherapy.

    Science.gov (United States)

    Pelliccia, Daniele; Crosbie, Jeffrey C; Larkin, Kieran G

    2016-08-21

    Recent image guidance developments for preclinical synchrotron microbeam radiotherapy represent a necessary step for future clinical translation of the technique. Image quality can be further improved using x-ray phase contrast, which is readily available at synchrotron facilities. We here describe a methodology for phase contrast image guidance at the Imaging and Medical Beamline at the Australian Synchrotron. Differential phase contrast is measured alongside conventional attenuation and used to improve the image quality. Post-processing based on the inverse Riesz transform is employed on the measured data to obtain noticeably sharper images. The procedure is extremely well suited for applications such as image guidance which require both visual assessment and sample alignment based on semi automatic image registration. Moreover, our approach can be combined with all other differential phase contrast imaging techniques, in all cases where a quantitative evaluation of the refractive index is not required. PMID:27436750

  5. Phase contrast image guidance for synchrotron microbeam radiotherapy

    Science.gov (United States)

    Pelliccia, Daniele; Crosbie, Jeffrey C.; Larkin, Kieran G.

    2016-08-01

    Recent image guidance developments for preclinical synchrotron microbeam radiotherapy represent a necessary step for future clinical translation of the technique. Image quality can be further improved using x-ray phase contrast, which is readily available at synchrotron facilities. We here describe a methodology for phase contrast image guidance at the Imaging and Medical Beamline at the Australian Synchrotron. Differential phase contrast is measured alongside conventional attenuation and used to improve the image quality. Post-processing based on the inverse Riesz transform is employed on the measured data to obtain noticeably sharper images. The procedure is extremely well suited for applications such as image guidance which require both visual assessment and sample alignment based on semi automatic image registration. Moreover, our approach can be combined with all other differential phase contrast imaging techniques, in all cases where a quantitative evaluation of the refractive index is not required.

  6. Space charge tracking code for a synchrotron accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ottinger, M.B.; Tajima, T. [Univ. of Texas, Austin, TX (United States); Hiramoto, K. [Hitachi Ltd., Hitachi, Ibaraki (Japan). Hitachi Research Lab.

    1997-06-01

    An algorithm has been developed to compute particle tracking, including self-consistent space charge effects for synchrotron accelerators. In low-energy synchrotrons space charge plays a central role in enhancing emittance of the beam. The space charge effects are modeled by mutually interacting (through the Coulombic force) N cylindrical particles (2-{1/2}-dimensional dynamics) whose axis is in the direction of the equilibrium particle flow. On the other hand, their interaction with synchrotron lattice magnets is treated with the thin-lens approximation and in a fully 3-dimensional way. Since the existing method to treat space charge fully self-consistently involved 3-D space charge effect computation, the present method allows far more realistic physical parameters and runs in far shorter time (about 1/20). Some examples on space charge induced instabilities are presented.

  7. National synchrotron light source medical personnel protection interlock

    International Nuclear Information System (INIS)

    This report is founded on reports written in April 1987 by Robert Hettel for angiography operations at the Stanford Synchrotron Research Laboratory (SSRL) and a subsequent report covering angiography operations at the National Synchrotron Light Source (NSLS); BNL Informal Report 47681, June 1992. The latter report has now been rewritten in order to accurately reflect the design and installation of a new medical safety system at the NSLS X17B2 beamline Synchrotron Medical Research Facility (SMERF). Known originally as the Angiography Personnel Protection Interlock (APPI), this system has been modified to incorporate other medical imaging research programs on the same beamline and thus the name has been changed to the more generic Medical Personnel Protection Interlock (MPPI). This report will deal almost exclusively with the human imaging (angiography, bronchography, mammography) aspects of the safety system, but will briefly explain the modular aspects of the system allowing other medical experiments to be incorporated

  8. The challenges of third-generation synchrotron light source

    International Nuclear Information System (INIS)

    Third-generation synchrotron light sources are specifically designed to operate with long insertion devices that produce very high brightness beams of synchrotron radiation. There are many such facilities now under construction, or in the design stage, all over the world. After a brief review of the main properties of the low emittance storage rings that form the heart of these facilities, we will discuss the particular challenges that accompany their design. These include: the effects of the strong sextupoles required for chromatic correction of the low emittance lattices; impact of machine imperfections on the dynamic aperture; the effects of the linear and nonlinear magnetic fields of the undulators; impedance consequences of long, narrow, undulator vacuum vessels; injection; and beam lifetime. As examples, we take the Advanced Light Source, currently under construction at the Lawrence Berkeley Laboratory, USA, and the European Synchrotron Radiation Facility under construction in Grenoble, France. 8 refs., 8 figs., 1 tab

  9. Applications of synchrotron x-ray fluorescence to extraterrestrial materials

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, S.R.; Rivers, M.L.; Smith, J.V.

    1986-01-01

    Synchrotron x-ray fluorescence (SXRF) is a valuable technique for trace element analyses of extraterrestrial materials permitting minimum detection limits less than 1 ppM for 20 micrometer spots. SXRF measurements have been performed on iron meteorites and micrometeorites using white synchrotron radiation and an energy dispersive x-ray detector at the National Synchrotron Light Source (X-26C), Brookhaven National Laboratory (NY). Partitioning of Cu between troilite (FeS) and metal in the nine iron meteorites studied suggests sub-solidus re-equilibration in these objects. A technique has been developed for determining self-absorption corrections for filtered, continuum excitation of small specimens, such as stratospheric particles and refractory inclusions in meteorites.

  10. Rising dough and baking bread at the Australian synchrotron

    Science.gov (United States)

    Mayo, S. C.; McCann, T.; Day, L.; Favaro, J.; Tuhumury, H.; Thompson, D.; Maksimenko, A.

    2016-01-01

    Wheat protein quality and the amount of common salt added in dough formulation can have a significant effect on the microstructure and loaf volume of bread. High-speed synchrotron micro-CT provides an ideal tool for observing the three dimensional structure of bread dough in situ during proving (rising) and baking. In this work, the synchrotron micro-CT technique was used to observe the structure and time evolution of doughs made from high and low protein flour and three different salt additives. These experiments showed that, as expected, high protein flour produces a higher volume loaf compared to low protein flour regardless of salt additives. Furthermore the results show that KCl in particular has a very negative effect on dough properties resulting in much reduced porosity. The hundreds of datasets produced and analysed during this experiment also provided a valuable test case for handling large quantities of data using tools on the Australian Synchrotron's MASSIVE cluster.

  11. Synchrotron X-ray induced solution precipitation of nanoparticles

    CERN Document Server

    Lee, H J; Hwu, Y; Tsai, W L

    2003-01-01

    By irradiating a solution in electroless Ni deposition using synchrotron X-rays, Ni composite was found to nucleate homogeneously and eventually precipitate in the form of nanoparticles. The size of the nanoparticles precipitated is rather uniform (100-300 nm depending on the applied temperature). By the addition of an organic acid, well-dispersed nanoparticles could be effectively deposited on glass substrate. The hydrated electrons (e sub a sub q sup -), products of radiolysis of water molecules by synchrotron X-rays, may be responsible for the effective reduction of the metal ions, resulting in homogeneous nucleation and nanoparticle formation. Our results suggest that synchrotron X-ray can be used to induce solution precipitation of nanoparticles and therefore lead to a new method of producing nanostructured particles and coating.

  12. 6th International School “Synchrotron Radiation and Magnetism”

    CERN Document Server

    Bulou, Hervé; Joly, Loic; Scheurer, Fabrice; Magnetism and Synchrotron Radiation : Towards the Fourth Generation Light Sources

    2013-01-01

     Advances in the synthesis of new materials with often complex, nano-scaled structures require increasingly sophisticated experimental techniques that can probe the electronic states, the atomic magnetic moments and the magnetic microstructures responsible for the properties of these materials. At the same time, progress in synchrotron radiation techniques has ensured that these light sources remain a key tool of investigation, e.g. synchrotron radiation sources of the third generation are able to support magnetic imaging on a sub-micrometer scale. With the Sixth Mittelwihr School on Magnetism and Synchrotron Radiation the tradition of teaching the state-of-the-art on modern research developments continues and is expressed through the present set of extensive lectures provided in this volume. While primarily aimed at postgraduate students and newcomers to the field, this volume will also benefit researchers and lecturers actively working in the field.

  13. High Intensity Beam Issues in the CERN Proton Synchrotron

    CERN Document Server

    Aumon, Sandra; Rivkin, Leonid

    This PhD work is about limitations of high intensity proton beams observed in the CERN Proton Synchrotron (PS) and, in particular, about issues at injection and transition energies. With its 53 years, the CERN PS would have to operate beyond the limit of its performance to match the future requirements. Beam instabilities driven by transverse impedance and aperture restrictions are important issues for the operation and for the High-Luminosity LHC upgrade which foresees an intensity increase delivered by the injectors. The main subject of the thesis concerns the study of a fast transverse instability occurring at transition energy. The proton beams crossing this energy range are particularly sensitive to wake forces because of the slow synchrotron motion. This instability can cause a strong vertical emittance blow-up and severe losses in less than a synchrotron period. Experimental observations show that the particles at the peak density of the beam longitudinal distribution oscillate in the vertical plane du...

  14. Transvenous coronary angiography in humans with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Thomlinson, W.

    1994-10-01

    The transvenous coronary angiography project at the National Synchrotron Light Source (NSLS) is presently undergoing a significant upgrade to the hardware and software in the synchrotron medical facility. When completed, the project will have reached a level of maturity in the imaging technology which will allow the research team to begin to concentrate on medical research programs. This paper will review the status of the project and imaging technology and will discuss the current upgrades and future advanced technology initiatives. The advantages of using the radiation from a synchrotron, over that from a standard x-ray source, were the motivation for the project. A total of 23 human imaging sessions have been carried out with in the project. The primary goals have been to establish the imaging parameters and protocol necessary to obtain clinically useful images.

  15. Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Leone, Stephen R.; Ahmed, Musahid; Wilson, Kevin R.

    2010-03-14

    Scientists at the Chemical Dynamics Beamline of the Advanced Light Source in Berkeley are continuously reinventing synchrotron investigations of physical chemistry and chemical physics with vacuum ultraviolet light. One of the unique aspects of a synchrotron for chemical physics research is the widely tunable vacuum ultraviolet light that permits threshold ionization of large molecules with minimal fragmentation. This provides novel opportunities to assess molecular energetics and reaction mechanisms, even beyond simple gas phase molecules. In this perspective, significant new directions utilizing the capabilities at the Chemical Dynamics Beamline are presented, along with an outlook for future synchrotron and free electron laser science in chemical dynamics. Among the established and emerging fields of investigations are cluster and biological molecule spectroscopy and structure, combustion flame chemistry mechanisms, radical kinetics and product isomer dynamics, aerosol heterogeneous chemistry, planetary and interstellar chemistry, and secondary neutral ion-beam desorption imaging of biological matter and materials chemistry.

  16. HSC5: synchrotron radiation and neutrons for cultural heritage studies

    International Nuclear Information System (INIS)

    Synchrotron and neutron sources offer recent and additional insight into the records of our cultural past. Over the last years, there has been an increasing demand for access to synchrotron radiation- and neutron-based techniques, and their applications in the fields of archaeological science and cultural heritage. The purpose of this Hercules Specialized Course is to give the participants an introduction to the basic principles of synchrotron radiation and neutron techniques (imaging, microscopy, diffraction, absorption and fluorescence, IR spectroscopy). The school provides cross-disciplinary examples illustrating the abilities of these techniques in a representative range of scientific cases concerning painting, archaeological artefacts, inks, pigments, fossils and the Dead Sea scrolls. This document gathers only the resumes of the lectures

  17. RF-knockout Extraction System for the CNAO Synchrotron

    CERN Document Server

    Carmignani, Nicola; Serio, Mario; Balbinot, Giovanni; Bressi, Erminia; Caldara, Michele; Pullia, Marco; Bosser, Jacques; Venchi, Giuseppe

    2010-01-01

    The National Centre for Oncological Hadrontherapy (CNAO) is a centre in Italy for the treatment of patients affected by tumours with proton and carbon ions beams accelerated in a synchrotron. The synchrotron extraction method is based on the use of a betatron core. This work aims to verify, through a theoretical study and a simulation, the possibility of using the RF-knockout extraction method exploiting the existing hardware. A simulation program has been written to simulate the extraction system of the synchrotron with the purpose to define the parameters of the radio frequency. Two types of radio frequencies have been compared in order to obtain a constant spill with the minimum ripple: a carrier wave with a frequency and amplitude modulation, and a gaussian narrow band noise modulated in amplitude. Results of the simulation and considerations on the kicker characteristics are presented

  18. Transvenous coronary angiography in humans with synchrotron radiation

    International Nuclear Information System (INIS)

    The transvenous coronary angiography project at the National Synchrotron Light Source (NSLS) is presently undergoing a significant upgrade to the hardware and software in the synchrotron medical facility. When completed, the project will have reached a level of maturity in the imaging technology which will allow the research team to begin to concentrate on medical research programs. This paper will review the status of the project and imaging technology and will discuss the current upgrades and future advanced technology initiatives. The advantages of using the radiation from a synchrotron, over that from a standard x-ray source, were the motivation for the project. A total of 23 human imaging sessions have been carried out with in the project. The primary goals have been to establish the imaging parameters and protocol necessary to obtain clinically useful images

  19. HSC5: synchrotron radiation and neutrons for cultural heritage studies

    Energy Technology Data Exchange (ETDEWEB)

    Michel, Anne [Institut Neel - CNRS, 38 - Grenoble (France); Artioli, G. [Padova Univ. (Italy); Bleuet, P.; Cotte, M.; Tafforeau, P.; Susini, J. [European Synchrotron Radiation Facility, 38 - Grenoble (France); Dumas, P.; Somogyl, A. [SOLEIL Synchrotron, 91 - Gif sur Yvette (France); Cotte, M. [Centre de Recherche et de Restauration des Musees de France, UMR171, 75 - Paris (France)]|[European Synchrotron Radiation Facility, 38 - Grenoble (France); Kockelmann, W. [Science and Technology Facilities Council, Rutherford Appleton Lab. (United Kingdom); Kolar, J. [Ljubljana Univ., Morana RTD, Slovenia, Faculty of Chemistry and Chemical Technology (Slovenia); Areon, I. [Nova Gorica Univ. (Slovenia); Meden, A.; Strlie, M. [Ljubljana Univ., Faculty of Chemistry and Chemical Technology (Slovenia); Pantos, M. [Daresbury Laboratory, Warrington (United Kingdom); Vendrell, M. [Barcelona Univ., dept. of Crystallography and Mineralogy (Spain); Wess, T. [Cardiff Univ., School of Optometry and Institute of Vision (Ireland); Gunneweg, J. [Hebrew Univ., Jerusalem (Israel)

    2007-07-01

    Synchrotron and neutron sources offer recent and additional insight into the records of our cultural past. Over the last years, there has been an increasing demand for access to synchrotron radiation- and neutron-based techniques, and their applications in the fields of archaeological science and cultural heritage. The purpose of this Hercules Specialized Course is to give the participants an introduction to the basic principles of synchrotron radiation and neutron techniques (imaging, microscopy, diffraction, absorption and fluorescence, IR spectroscopy). The school provides cross-disciplinary examples illustrating the abilities of these techniques in a representative range of scientific cases concerning painting, archaeological artefacts, inks, pigments, fossils and the Dead Sea scrolls. This document gathers only the resumes of the lectures.

  20. Evidence for Synchrotron Bubbles from GRS 1915+105

    CERN Document Server

    Ishwara-Chandra, C H; Rao, A P

    2002-01-01

    We present GMRT observations of the Galactic microquasar GRS 1915+105 at 1.28 GHz for 8 days from 2001 June 18 to July 1. We have seen several isolated radio flares of varying magnitudes (20 - 50 mJy) and durations (6 - 35 min) and we model them as due to adiabatically expanding synchrotron emitting clouds (synchrotron bubbles) ejected from the accretion disk. By applying this model, we provide a new method to estimate the electron power-law index p, hence the spectral index, from single frequency radio observations. This method does not require correction for the optical depth time delay effects which may be important in the case of optically thick radio emission. Using our estimated value of p and simultaneous multiwavelength data from literature, we have calculated the time of ejection of the synchrotron plasma and the time delays at different observed frequencies. Our estimates are in good agreement with the observed time delays.

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

    CERN Document Server

    Giacomini, J C

    1996-01-01

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

  2. Synchrotron based planar imaging and digital tomosynthesis of breast and biopsy phantoms using a CMOS active pixel sensor.

    Science.gov (United States)

    Szafraniec, Magdalena B; Konstantinidis, Anastasios C; Tromba, Giuliana; Dreossi, Diego; Vecchio, Sara; Rigon, Luigi; Sodini, Nicola; Naday, Steve; Gunn, Spencer; McArthur, Alan; Olivo, Alessandro

    2015-03-01

    The SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline at Elettra is performing the first mammography study on human patients using free-space propagation phase contrast imaging. The stricter spatial resolution requirements of this method currently force the use of conventional films or specialized computed radiography (CR) systems. This also prevents the implementation of three-dimensional (3D) approaches. This paper explores the use of an X-ray detector based on complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology as a possible alternative, for acquisitions both in planar and tomosynthesis geometry. Results indicate higher quality of the images acquired with the synchrotron set-up in both geometries. This improvement can be partly ascribed to the use of parallel, collimated and monochromatic synchrotron radiation (resulting in scatter rejection, no penumbra-induced blurring and optimized X-ray energy), and partly to phase contrast effects. Even though the pixel size of the used detector is still too large - and thus suboptimal - for free-space propagation phase contrast imaging, a degree of phase-induced edge enhancement can clearly be observed in the images. PMID:25498332

  3. Design Parameters of a High-Power Proton Synchrotron for Neutrino Beams at CERN

    CERN Document Server

    Papaphilippou, Y; Efthymiopoulos, I; Gerigk, F; Steerenberg, R

    2012-01-01

    Design studies have been initiated at CERN for exploring the prospects of future high-power proton beams for producing neutrinos within the LAGUNA-LBNO project. These studies include a possible increase of the SPS beam power from 500kW to 700kW for a new conventional neutrino beam line based on the CNGS technology, and at a second stage a 2 MW High-Power Proton Synchrotron (HP-PS) using the Low Power Superconducting Proton Linac (LP-SPL) as injector. A low energy 5GeV-4MW neutrino super-beam alternative based on a high-power version of SPL is also considered. This paper concentrates on the HP-PS by exploring the parameter space and constraints regarding beam characteristics, machine hardware and layout, for reaching the 2 MW average beam power.

  4. A study of the chemical budget of Lake Baikal using neutron activation and synchrotron radiation

    International Nuclear Information System (INIS)

    Beginning in 1993, neutron activation analysis (NAA) and synchrotron radiation X-ray fluorescence analysis (SRXFA) have been used to investigate the composition of particles suspended in Lake Baikal and its major tributaries. Both techniques have provided data on the concentration of a wide range of elements with neutron activation offering the first data on several rare earth elements and other minor elements. While each technique appears to be more suitable for determining the concentration of certain elements than an alternate technique, both techniques are in close agreement in their analysis of most of the elements studied. International standard reference materials were used to calibrate and validate the analyses and allow results from the two methods to be compared. The results of this study have been combined with published data to calculate the total elemental input into the lake

  5. Development of polishing methods for Chemical Vapor Deposited Silicon Carbide mirrors for synchrotron radiation

    International Nuclear Information System (INIS)

    Material properties of Chemical Vapor Deposited Silicon Carbide (CVD SiC) make it ideal for use in mirrors for synchrotron radiation experiments. We developed methods to grind and polish flat samples of CVD SiC down to measured surface roughness values as low as 1.1 Angstroms rms. We describe the processing details, including observations we made during trial runs with alternative processing recipes. We conclude that pitch polishing using progressively finer diamond abrasive, augmented with specific water based lubricants and additives, produces superior results. Using methods based on these results, a cylindrical and a toroidal mirror, each about 100 x 300mm, were respectively finished by Continental Optical and Frank Cooke, Incorporated. WYCO Interferometry shows these mirrors have surface roughness less than 5.7 Angstroms rms. These mirrors have been installed on the LLNL/UC X-ray Calibration and Standards Facility at the Stanford Synthrotron Radiation Laboratory

  6. Filter and window assemblies for high power insertion device synchrotron radiation sources

    International Nuclear Information System (INIS)

    The powerful beams of x-ray radiation generated by insertion devices at high power synchrotron facilities deposit substantial amounts of localized heat in the front end and optical components that they intercept. X-ray beams from undulator sources, in particular, are confined to very narrow solid angles and therefore impose very high absorbed heat fluxes. This paper is devoted to a detailed study of the design of windows for the Advanced Photon Source undulators and wigglers, emphasizing alternative design concepts, material considerations, and cooling techniques necessary for handling the high heat load of the insertion devices. Various designs are thermally and structurally analyzed by numerically simulating full-power operating conditions. This analysis also has relevance to the design and development of other beam line components which are subjected to the high heat loads of insertion devices

  7. Synchrotron X-ray analyses in art and archaeology

    International Nuclear Information System (INIS)

    X-ray synchrotron techniques play an increasingly important part in the analysis strategy of archaeological materials, in order to determine the source materials, their provenance and the ancient techniques of preparation. In favourable cases, the microstructure (crystallite size and deformation) can be interpreted as a residual mark of the elaboration techniques and origin of ancient polycrystalline materials. Our study on cosmetic recipes and make-up manufacturing in Antiquity, illustrates some possible applications of non-destructive synchrotron techniques, complementing other standard analytical tools

  8. Characteristics of synchrotron radiation and of its sources

    International Nuclear Information System (INIS)

    Synchrotron light emission and the classical relativistic electromagnetic theory describing it are reviewed. The electron optics of storage rings are considered in some detail, beginning with the ideal electron orbit and the distribution which electrons take around it. This is folded with the process of synchrotron light emission itself to define the effective photon source. The predictions of classical relativistic theory are compared with experiment, and one finds agreement within the experimental uncertainties. Further refinements, such as wiggler magnets and free electron lasers are also considered

  9. Study of beam dynamics at cooler synchrotron TARN-II

    International Nuclear Information System (INIS)

    Several kinds of beam diagnostic instruments, have been developed at cooler-synchrotron TARN-II. These are intended to study beam dynamics at low beam current of several microamperes and then have high sensitivity of good S/N ratio. In addition, the acceleration system, especially low level RF system, has been improved to attain the maximum beam energy. With the successful performance of these instrumentations, the study of beam dynamics are presently being carried out. For example, the synchrotron acceleration of the light ions was achieved up to 220 MeV/u without any beam loss. (author)

  10. Synchrotron radiation sources INDUS-1 and INDUS-2

    International Nuclear Information System (INIS)

    The synchrotron radiation sources, INDUS-1 and INDUS-2 are electron storage rings of 450 MeV and 2 GeV beam energies respectively. INDUS-1 is designed to produce VUV radiation whereas INDUS-2 will be mainly used to produce x-rays. INDUS-1 is presently undergoing commissioning whereas INDUS-2 is under construction. Both these rings have a common injector system comprising of a microtron and a synchrotron. Basic design features of these sources and their injector system are discussed in this paper. The radiation beamlines to be set up on these sources are also described. (author)

  11. X-ray intensity interferometer for synchrotron radiation

    International Nuclear Information System (INIS)

    We propose to measure the transverse coherence of an x-ray beam, for the first time, by Hanbury Brown intensity interferometry. Our approach is to use an intensity interferometer adapted to the soft x-ray region. The X1 or X13 soft x-ray undulator at the National Synchrotron Light Source will supply the partially coherent x-rays. We are developing this technique to characterize the coherence properties of x-ray beams from high brilliance insertion devices at third-generation synchrotron light facilities such as the Advanced Photon Source

  12. Energy dispersive spectroscopy using synchrotron radiation: intensity considerations

    International Nuclear Information System (INIS)

    Detailed considerations are given to the reliability of energy dependent integrated intensity data collected from the pressure cavity of a diamond-anvil pressure cell illuminated with heterochromatic radiation from a synchrotron storage ring. It is demonstrated that at least in one run, the electron beam current cannot be used to correct for energy-intensity variations of the incident beam. Rather there appears to be an additional linear relationship between the decay of the synchrotron beam and the magnitude of the background intensity. 13 refs., 7 figs

  13. Measurement of accelerated electron beam current at the Erevan synchrotron

    International Nuclear Information System (INIS)

    A system which ensures high accuracy of accelerated electro n beam current measurement at the synchrotron is described. The expected limits for the frequency characteristic of the measured magnitude, i.e. current of accelerated electron beam, are analyzed. A structure of measurement devices ensuring a necessary frecuency range for measured signals is chosen. A magnetoinduction feedback converter operating in aperiodic mode is taken as a primary beam current monitor. The parameters of the converter with a coincidence amplifier were calculated with a computer. Oscillograms of accelerated electron beam current corresponding to different operational modes of the synchrotron are presented

  14. RF-system design of proton synchrotron for hadron therapy

    International Nuclear Information System (INIS)

    A conceptual design of the RF-system for the medical proton synchrotron is presented. The synchrotron will be able to accelerate high-intensity proton beam of 6.25 · 1010 protons per pulse till the energy of 60 - 220 MeV with the repetition rate of 1 Hz. The RF-system consists of a RF-cavity with a magnetic material, a power amplifier, a tuning control system and a beam control system. The RF-system must supply 2 kV peak voltage in the frequency range from 1 to 5 MHz

  15. SYNCHROTRON RADIATION XRF MICROPROBE STUDY OF HUMAN BONE TUMOR SLICE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The experimental apparatus of X-ray fluorescence (XRF) microprobe analysis at Beijing Synchrotron Radiation Facility (BSRF) is described Using the bovine liver as the standard reference.the minimum detection limit(MDL) of trace element was measured to determine the capability of biological sample analysis by synchrotron radiation XRF microprobe.The relative change of the content of the major or trace element in the normal and tumor part of human bone tissue slice was investigated The experimental result relation to the clinical medicine was also discussed.

  16. Extended 1D Method for Coherent Synchrotron Radiation including Shielding

    CERN Document Server

    Sagan, David; Mayes, Christopher; Sae-Ueng, Udom

    2008-01-01

    Coherent Synchrotron Radiation can severely limit the performance of accelerators designed for high brightness and short bunch length. Examples include light sources based on ERLs or FELs, and bunch compressors for linear colliders. In order to better simulate Coherent Synchrotron Radiation, the established 1-dimensional formalism is extended to work at lower energies, at shorter bunch lengths, and for an arbitrary configuration of multiple bends. Wide vacuum chambers are simulated by means of vertical image charges. This formalism has been implemented in the general beam dynamics code "Bmad" and its results are here compared to analytical approximations, to numerical solutions of the Maxwell equations, and to the simulation code "elegant".

  17. Design of a wire imaging synchrotron radiation detector

    International Nuclear Information System (INIS)

    This paper documents the design of a detector invented to measure the positions of synchrotron radiation beams for the precision energy spectrometers of the Stanford Linear Collider (SLC). The energy measurements involve the determination, on a pulse-by-pulse basis, of the separation of pairs of intense beams of synchrotron photons in the MeV energy range. The detector intercepts the beams with arrays of fine wires. The ejection of Compton recoil electrons results in charges being developed in the wires, thus enabling a determination of beam positions. 10 refs., 4 figs

  18. Challenges in Biology and Medicine with Synchrotron Infrared Light

    International Nuclear Information System (INIS)

    The brightness (or brilliance) of synchrotron radiation was exploited in infrared microspectroscopy. Among application of this synchrotron-based microanalytical technique, biological and biomedical investigations, at the diffraction-limited spot size, are exhibit of an increasing interest among almost all the existing infrared beamline worldwide. This paper is presenting the main properties of such a source, coupled with an infrared microscope. Several important applications in biomedical field are reported: cancer cells studies and drug effects, human substantia nigra in Parkinson's disease, β-amyloids deposits in Alzheimer's disease. (authors)

  19. Design and optimization of the lattice of the superconducting synchrotron SIS300 for slow extraction

    International Nuclear Information System (INIS)

    The superconducting synchrotron SIS300 is planned to be built at the new Facility for Antiproton and Ion Research (FAIR), at GSI-Darmstadt. SIS300 will be a versatile machine, which by means of a low-energy stretcher-mode or a high-energy ramped-mode will provide slowly extracted heavy ion beams towards the experimental areas. To reach the required maximum field of 4.5 T, cos(θ) magnets are necessary. Thus, SIS300 will become the first superconducting synchrotron worldwide with cos(θ) magnets providing resonant slow extraction. Since SIS300 will be installed in the same tunnel as the SIS100 synchrotron, the dipole layout of SIS300 cannot be freely chosen. Thus, a standard lattice cannot be applied. A redesign of the SIS300 lattice accepting compromises concerning the positions and phase advances between the optical elements has been proposed. Using the analytical model of the slow extraction, firstly proposed by Kobayashi, and the analytical description of the resonance driving modes, a multiobjective optimization algorithm has been developed for the optimization of the lattice under the given boundary conditions. The final goal of the lattice optimization is a higher efficiency of the slow extraction. The results are evaluated by means of tracking simulations performed with the code Elegant. The field quality in superconducting cos(θ) magnets is determined by the positions of the superconducting cable and the static and time-dependent effects of the current in the cable. Furthermore, the fast ramp rates of 1 T/s in the dipoles, which are fifty times faster than in any other superconducting cos(θ) magnet, together with the fact that the aperture is smaller than in conventional accelerator magnets, makes it extremely difficult to obtain a high-quality magnetic field. The unavoidable field errors affect the beam dynamics and worsen the slow extraction efficiency. Therefore, the field errors in the SIS300 dipoles have been estimated, and their effects have been

  20. Design and optimization of the lattice of the superconducting synchrotron SIS300 for slow extraction

    Energy Technology Data Exchange (ETDEWEB)

    Saa Hernandez, Angela

    2011-10-15

    The superconducting synchrotron SIS300 is planned to be built at the new Facility for Antiproton and Ion Research (FAIR), at GSI-Darmstadt. SIS300 will be a versatile machine, which by means of a low-energy stretcher-mode or a high-energy ramped-mode will provide slowly extracted heavy ion beams towards the experimental areas. To reach the required maximum field of 4.5 T, cos({theta}) magnets are necessary. Thus, SIS300 will become the first superconducting synchrotron worldwide with cos({theta}) magnets providing resonant slow extraction. Since SIS300 will be installed in the same tunnel as the SIS100 synchrotron, the dipole layout of SIS300 cannot be freely chosen. Thus, a standard lattice cannot be applied. A redesign of the SIS300 lattice accepting compromises concerning the positions and phase advances between the optical elements has been proposed. Using the analytical model of the slow extraction, firstly proposed by Kobayashi, and the analytical description of the resonance driving modes, a multiobjective optimization algorithm has been developed for the optimization of the lattice under the given boundary conditions. The final goal of the lattice optimization is a higher efficiency of the slow extraction. The results are evaluated by means of tracking simulations performed with the code Elegant. The field quality in superconducting cos({theta}) magnets is determined by the positions of the superconducting cable and the static and time-dependent effects of the current in the cable. Furthermore, the fast ramp rates of 1 T/s in the dipoles, which are fifty times faster than in any other superconducting cos({theta}) magnet, together with the fact that the aperture is smaller than in conventional accelerator magnets, makes it extremely difficult to obtain a high-quality magnetic field. The unavoidable field errors affect the beam dynamics and worsen the slow extraction efficiency. Therefore, the field errors in the SIS300 dipoles have been estimated, and their