WorldWideScience

Sample records for modem synchrotron beams

  1. Multi turn beam extraction from synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Tsoupas, Nicholaos

    2017-01-24

    This disclosure relates to apparatuses and methods for the extraction of particle beams while maintaining the energy levels and precision of the particles and the particle beam. Apparatuses and methods for extracting a charged particle beam from a central orbit in a synchrotron are provided, in which a particle beam is deflected from the central orbit. Parts of the deflected particle beam passes through a stripping foil placed in at least parts of the deflected path such that the particles that pass through the foil are stripped of at least one electron. The electron stripped particles and the non-stripped particles may be separated magnetically.

  2. 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.

  3. Beam halo collimation in heavy ion synchrotrons

    Science.gov (United States)

    Strašík, I.; Prokhorov, I.; Boine-Frankenheim, O.

    2015-08-01

    This paper presents a systematic study of the halo collimation of ion beams from proton up to uranium in synchrotrons. The projected Facility for Antiproton and Ion Research synchrotron SIS100 is used as a reference case. The concepts are separated into fully stripped (e.g., 238U92+ ) and partially stripped (e.g., 238U28+ ) ion collimation. An application of the two-stage betatron collimation system, well established for proton accelerators, is intended also for fully stripped ions. The two-stage system consists of a primary collimator (a scattering foil) and secondary collimators (bulky absorbers). Interaction of the particles with the primary collimator (scattering, momentum losses, and nuclear interactions) was simulated by using fluka. Particle-tracking simulations were performed by using mad-x. Finally, the dependence of the collimation efficiency on the primary ion species was determined. The influence of the collimation system adjustment, lattice imperfections, and beam parameters was estimated. The concept for the collimation of partially stripped ions employs a thin stripping foil in order to change their charge state. These ions are subsequently deflected towards a dump location using a beam optical element. The charge state distribution after the stripping foil was obtained from global. The ions were tracked by using mad-x.

  4. 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...

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

    CERN Document Server

    Petracca, Stefania

    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.

  6. Beam Diagnostics for the J-PARC Main Ring Synchrotron

    CERN Document Server

    Toyama, Takeshi; Hashimoto, Yoshinori; Hayashi, Naoki; Kishiro, Junichi; Lee, Seishu; Miura, Takako; Muto, Suguru; Toyokawa, Ryoji

    2005-01-01

    Beam diagnostics: beam intensity monitors (DCCT, SCT, FCT, WCM), beam position monitors (ESM), beam loss monitors (proportional chamber, air ion chamber), beam profile monitors (secondary electron emission, gas-sheet) have been designed, tested, and will be installed for the Main Ring synchrotron of J-PARC (Japan Proton Accelerator Research Complex). This paper describes the basic design principle and specification of each monitor, with a stress on how to cope with high power beam (average circulation current of ~12 A) and low beam loss operation (less than 1 W/m except a collimator region). Some results of preliminary performance test using present beams and a radiation source will be reported.

  7. Turn-By Beam Extraction during Acceleration in a Synchrotron

    Science.gov (United States)

    Tsoupas, Nicholaos; Trbojevic, Dejan

    2014-02-01

    A synchrotron to accelerate protons or carbon ions for medical applications is being designed at Brookhaven National Laboratory (BNL). Single beam bunches with maximum beam energy of 1.18 GeV and 400 MeV/u for protons and carbon ions respectively will be extracted from the synchrotron at 15 Hz. For protons, the maximum required energy for irradiating a tumor is ˜206 MeV. A pencil-like proton beam containing ˜5.4×107 p/bunch delivers a therapeutic dose of 2.5 Gy in ˜1.5 minutes to treat a tumor of 1 liter volume. It will take ˜80 minutes with bunches containing 4.5×104 ions/bunch to deliver the same dose of 2.5 Gy with a 400 MeV/u pencil-like carbon beam. This extended treatment time when using carbon ions is not acceptable. In addition, the synchrotron cannot be controlled with a beam bunch containing such a low number of carbon ions. To overcome these two problems of the extended treatment time and the low bunch intensity required for the treatment when carbon ions are used, we have devised a method to “peel” the required 4.5×104 carbon-ions/bunch from the accelerating carbon beam bunch containing ˜108 ions/bunch and deliver them to the tumor on a “turn-by-turn” basis. Unlike other methods of beam extraction from a synchrotron, such as resonance extraction, this method does not allow for any beam losses during the extraction and the carbon beam can be peeled off in less than 15 ms during the acceleration or deceleration cycle of the synchrotron. Thus, this turn-by-turn beam extraction method provides beam with variable energy and precisely controlled beam current during the 30 ms acceleration or deceleration time.

  8. Beam model for non-planar orbits in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Month, M.

    1984-03-26

    A framework has been developed for a beam model in the case of synchrotron orbits not confined to a plane. An appropriate moving reference system for the analysis of beam stability has been introduced. As examples of strong perturbations to median plane symmetry, two geometries for the overpass for the Tevatron collider are considered.

  9. 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...

  10. Enhancing the accelerated beam current in the booster synchrotron by optimizing the transport line beam propagation

    Indian Academy of Sciences (India)

    Saini R S; Tyagi Y; Ghodke A D; Puntambekar T A

    2016-04-01

    In this paper, we present the results of transverse beam emittance and twiss parameter measurement of an electron beam, delivered by a 20 MeV microtron which is used as a pre-injector system for a booster synchrotron in the Indus Accelerator Facility at RRCAT Indore. Based on these measured beam parameters, beam optics of a transport line was optimized and its results are alsodiscussed in this paper. This beam transport line is used to transport the electron beam from the 20MeV microtron to the booster synchrotron. The booster synchrotron works as a main injector for Indus-1 and Indus-2 synchrotron radiation facilities. To optimize the beam optics of a transport linefor proper beam transmission through the line as well as to match the beam twiss parameters at the beam injection point of another accelerator, it is necessary to know the transverse beam emittance and twiss parameters of the beam coming from the first one. A MATLAB-based GUI program has been developed to calculate the beam emittance and twiss parameters, using quadrupole scanmethod. The measured parameters have been used for beam transport line optimization and twiss parameters matching at booster injection point. After this optimization, an enhancement of ∼50% beam current has been observed in the booster synchrotron.

  11. A phase-space beam position monitor for synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Samadi, Nazanin, E-mail: nazanin.samadi@usask.ca [University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK (Canada); Bassey, Bassey; Martinson, Mercedes [University of Saskatchewan, 116 Science Place, Saskatoon, SK (Canada); Belev, George; Dallin, Les; Jong, Mark de [Canadian Light Source, 44 Innovation Boulevard, Saskatoon, SK (Canada); Chapman, Dean [University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK (Canada)

    2015-06-25

    A system has been developed to measure the vertical position and angle of the electron beam at a single location from a synchrotron source. The system uses a monochromator tuned to the absorption edge of a contrast material and has a sensitivity comparable with other beam position monitors. The stability of the photon beam position on synchrotron beamlines is critical for most if not all synchrotron radiation experiments. The position of the beam at the experiment or optical element location is set by the position and angle of the electron beam source as it traverses the magnetic field of the bend-magnet or insertion device. Thus an ideal photon beam monitor would be able to simultaneously measure the photon beam’s position and angle, and thus infer the electron beam’s position in phase space. X-ray diffraction is commonly used to prepare monochromatic beams on X-ray beamlines usually in the form of a double-crystal monochromator. Diffraction couples the photon wavelength or energy to the incident angle on the lattice planes within the crystal. The beam from such a monochromator will contain a spread of energies due to the vertical divergence of the photon beam from the source. This range of energies can easily cover the absorption edge of a filter element such as iodine at 33.17 keV. A vertical profile measurement of the photon beam footprint with and without the filter can be used to determine the vertical centroid position and angle of the photon beam. In the measurements described here an imaging detector is used to measure these vertical profiles with an iodine filter that horizontally covers part of the monochromatic beam. The goal was to investigate the use of a combined monochromator, filter and detector as a phase-space beam position monitor. The system was tested for sensitivity to position and angle under a number of synchrotron operating conditions, such as normal operations and special operating modes where the photon beam is intentionally altered

  12. Optical Synchrotron Radiation Beam Imaging with a Digital Mask

    Energy Technology Data Exchange (ETDEWEB)

    Fiorito, R. B. [University of Maryland, College Park, MD (United States); Zhang, H. D. [University of Maryland, College Park, MD (United States); Corbett, W. J. [SLAC, Menlo Park, CA (United States); Fisher, A. S. [SLAC, Menlo Park, CA (United States); Mok, W. Y. [SLAC, Menlo Park, CA (United States); Tian, K. [SLAC, Menlo Park, CA (United States); Douglas, D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Wilson, F. G. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Mitsuhashi, T. M. [KEK, Tsukuba (Japan); Shkvarunets, A. G. [University of Maryland, College Park, MD (United States)

    2012-11-01

    We have applied a new imaging/optical masking technique, which employs a digital micro-mirror device (DMD) and optical synchrotron radiation (OSR), to perform high dynamic range (DR) beam imaging at the JLAB Energy Recovery Linac and the SLAC/SPEAR3 Synchrotron Light Source. The OSR from the beam is first focused onto the DMD to produce a primary image; selected areas of this image are spatially filtered by controlling the state of individual micro-mirrors; and finally, the filtered image is refocused onto a CCD camera. At JLAB this technique has been used successfully to view the beam halo with a DR ~ 105. At SPEAR3 the DMD was used to filter out the bright core of the stored beam to study the turn-by-turn dynamics of the 10-3 weaker injected beam. We describe the optical performance, present limitations and our plans to improve the DR of both experimental systems.

  13. Rapid cycling medical synchrotron and beam delivery system

    Science.gov (United States)

    Peggs, Stephen G [Port Jefferson, NY; Brennan, J Michael [East Northport, NY; Tuozzolo, Joseph E [Sayville, NY; Zaltsman, Alexander [Commack, NY

    2008-10-07

    A medical synchrotron which cycles rapidly in order to accelerate particles for delivery in a beam therapy system. The synchrotron generally includes a radiofrequency (RF) cavity for accelerating the particles as a beam and a plurality of combined function magnets arranged in a ring. Each of the combined function magnets performs two functions. The first function of the combined function magnet is to bend the particle beam along an orbital path around the ring. The second function of the combined function magnet is to focus or defocus the particle beam as it travels around the path. The radiofrequency (RF) cavity is a ferrite loaded cavity adapted for high speed frequency swings for rapid cycling acceleration of the particles.

  14. Synchrotron radiation based beam diagnostics at the Fermilab Tevatron

    CERN Document Server

    Thurman-Keup, R; Hahn, A; Hurh, P; Lorman, E; Lundberg, C; Meyer, T; Miller, D; Pordes, S; Valishev, A

    2011-01-01

    Synchrotron radiation has been used for many years as a beam diagnostic at electron accelerators. It is not normally associated with proton accelerators as the intensity of the radiation is too weak to make detection practical. However, if one utilizes the radiation originating near the edge of a bending magnet, or from a short magnet, the rapidly changing magnetic field serves to enhance the wavelengths shorter than the cutoff wavelength, which for more recent high energy proton accelerators such as Fermilab's Tevatron, tends to be visible light. This paper discusses the implementation at the Tevatron of two devices. A transverse beam profile monitor images the synchrotron radiation coming from the proton and antiproton beams separately and provides profile data for each bunch. A second monitor measures the low-level intensity of beam in the abort gaps which poses a danger to both the accelerator's superconducting magnets and the silicon detectors of the high energy physics experiments. Comparisons of measur...

  15. Optical synchrotron radiation beam imaging with a digital mask

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hao [Univ. of Maryland, College Park, MD (United States); Fiorito, Ralph [Univ. of Maryland, College Park, MD (United States); Corbett, Jeff [SLAC National Accelerator Lab., Menlo Park, CA (United States); Shkvarunets, Anatoly [Univ. of Maryland, College Park, MD (United States); Tian, Kai [SLAC National Accelerator Lab., Menlo Park, CA (United States); Fisher, Alan [SLAC National Accelerator Lab., Menlo Park, CA (United States); Douglas, D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wilson, F. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mok, W. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Mitsuhashi, T. [KEK, Tsukuba (Japan)

    2016-01-01

    The 3GeV SPEAR3 synchrotron light source operates in top-up injection mode with up to 500mA circulating in the storage ring (equivalently 392nC). Each injection pulse contains only 40-80 pC producing a contrast ratio between total stored charge and injected charge of about 6500:1. In order to study transient injected beam dynamics during User operations, it is desirable to optically image the injected pulse in the presence of the bright stored beam. In the present work this is done by re-imaging visible synchrotron radiation onto a digital micro-mirror-array device (DMD), which is then used as an optical mask to block out light from the bright central core of the stored beam. The physical masking, together with an asynchronously-gated, ICCD imaging camera makes it is possible to observe the weak injected beam component on a turn-by-turn basis. The DMD optical masking system works similar to a classical solar coronagraph but has some distinct practical advantages: i.e. rapid adaption to changes in the shape of the stored beam, high extinction ratio for unwanted light and minimum scattering from the primary beam into the secondary optics. In this paper we describe the DMD masking method, features of the high dynamic range point spread function for the SPEAR3 optical beam line and measurements of the injected beam in the presence of the stored beam.

  16. Beam dumps design and local radiation protection at TERA synchrotron.

    Science.gov (United States)

    Porta, A; Campi, F; Agosteo, S

    2005-01-01

    The realisation of the National Center of Hadrontherapy was funded by the Italian Government in 2002. The Centre will be built in the area of Pavia (Italy). The synchrotron designed in the framework of this programme will accelerate protons and carbon ions up to 250 MeV and 400 MeV u(-1), respectively. Some of the main aspects which were taken into account in the design of the acceleration system are the patient's safety and the beam control. From this point of view an important role is played by the beam dumps in the synchrotron ring and upstream of the extraction system. In particular, an horizontal and a vertical beam dump will be installed in the synchrotron ring: the former will be used for lowering the beam intensity and the latter for beam abortion. The dump at the extraction will absorb the particles during the mounting and the falling ramps of the synchrotron magnetic cycle, thus extracting only the flat top of the ion spill. Beam dumps can produce intense fields of secondary radiation (neutrons, charged light-hadrons and photons) and high rates of induced activity, since they can absorb the beam completely. Usually they have to be shielded to protect the electronics during machine operation and to attenuate the radiation dose below the limits imposed by the law when the personnel access to the synchrotron hall. The part of the shielding design of the beam dumps concerning with the acceleration of protons was made using Monte Carlo simulations with the FLUKA code. Both induced activity and secondary radiation were taken into account. The shields against secondary radiation produced by carbon ions were designed, referring only to secondary neutrons, taking double-differential distributions from the literature as sources for the FLUKA simulations. The induced activity from carbon ions interactions was estimated analytically, using the data generated by the EPAX 2 code. The dose-equivalent rates from the induced radionuclides were calculated at 1 m from the

  17. Beam loss monitors comparison at the CERN Proton Synchrotron

    CERN Document Server

    Gilardoni, S S; Effinger, E; Gil-Flores, J; Wienands, U

    2011-01-01

    CERN is planning the renovation and upgrade of the beam loss detection system for the Proton Synchrotron (PS). Improved performance in speed–to be able to monitor beam loss on a bunch-by-bunch basis–and in longterm stability–to reduce or avoid the need for periodic calibration–are aimed for. To select the most suitable technology, different detectors were benchmarked in the machine with respect to the same beam loss. The characteristics of the different detectors, the results of the measurement campaign and their suitability as future monitors for the PS are presented.

  18. Synchrotron radiation based beam diagnostics at the Fermilab Tevatron

    Science.gov (United States)

    Thurman-Keup, R.; Cheung, H. W. K.; Hahn, A.; Hurh, P.; Lorman, E.; Lundberg, C.; Meyer, T.; Miller, D.; Pordes, S.; Valishev, A.

    2011-09-01

    Synchrotron radiation has been used for many years as a beam diagnostic at electron accelerators. It is not normally associated with proton accelerators as the intensity of the radiation is too weak to make detection practical. However, if one utilizes the radiation originating near the edge of a bending magnet, or from a short magnet, the rapidly changing magnetic field serves to enhance the wavelengths shorter than the cutoff wavelength, which for more recent high energy proton accelerators such as Fermilab's Tevatron, tends to be visible light. This paper discusses the implementation at the Tevatron of two devices. A transverse beam profile monitor images the synchrotron radiation coming from the proton and antiproton beams separately and provides profile data for each bunch. A second monitor measures the low-level intensity of beam in the abort gaps which poses a danger to both the accelerator's superconducting magnets and the silicon detectors of the high energy physics experiments. Comparisons of measurements from the profile monitor to measurements from the flying wire profile systems are presented as are a number of examples of the application of the profile and abort gap intensity measurements to the modelling of Tevatron beam dynamics. Work supported by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.

  19. Measurement of Beam Loss at the Australian Synchrotron

    CERN Document Server

    Holzer, EB; Kastriotou, M; Boland, MJ; Jackson, PD; Rasool, RP; Schmidt, J; Welsch, CP

    2014-01-01

    The unprecedented requirements that new machines are setting on their diagnostic systems is leading to the development of new generation of devices with large dynamic range, sensitivity and time resolution. Beam loss detection is particularly challenging due to the large extension of new facilities that need to be covered with localized detector. Candidates to mitigate this problem consist of systems in which the sensitive part of the radiation detectors can be extended over long distance of beam lines. In this document we study the feasibility of a BLM system based on optical fiber as an active detector for an electron storage ring. The Australian Synchrotron (AS) comprises a 216m ring that stores electrons up to 3GeV. The Accelerator has recently claimed the world record ultra low transverse emittance (below pm rad) and its surroundings are rich in synchrotron radiation. Therefore, the AS provides beam conditions very similar to those expected in the CLIC/ILC damping rings. A qualitative benchmark of beam l...

  20. Beam stability in synchrotrons with digital transverse feedback systems in dependence on beam tunes

    Science.gov (United States)

    Zhabitsky, V. M.

    2012-07-01

    The beam stability problem in synchrotrons with a digital transverse feedback system (TFS) is studied. The TFS damper kicker (DK) corrects the transverse momentum of a bunch in proportion to its displacement from the closed orbit measured at the location of the beam position monitor (BPM). It is shown that the area and configuration of the beam stability separatrix depend on the beam tune, the feedback gain, the phase balance between the phase advance from BPM to DK and the phase response of the feedback chain at the betatron frequency.

  1. Modeling Longitudinal Oscillations of Bunched Beams in Synchrotrons

    CERN Document Server

    Klingbeil, Harald; Mehler, Monika; Zipfel, Bernhard

    2010-01-01

    Longitudinal oscillations of bunched beams in synchrotrons have been analyzed by accelerator physicists for decades, and a closed theory is well-known [1]. The first modes of oscillation are the coherent dipole mode, quadrupole mode, and sextupole mode. Of course, these modes of oscillation are included in the general theory, but for developing RF control systems, it is useful to work with simplified models. Therefore, several specific models are analyzed in the paper at hand. They are useful for the design of closed-loop control systems in order to reach an optimum performance with respect to damping the different modes of oscillation. This is shown by the comparison of measurement and simulation results for a specific closed-loop control system.

  2. Optical substrate materials for synchrotron radiation beam lines

    Science.gov (United States)

    Howells, Malcolm R.; Paquin, Roger A.

    1997-09-01

    We consider the materials choices available for making optical substrates for synchrotron radiation beam lines. We 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 we explore the issues of dimensional stability, polishing, bending, cooling, and manufacturing strategy. We conclude that metals are best from an engineering and cost standpoint while the ceramics are best from a polishing standpoint. We then give discussions of specific materials as follows: silicon carbide, silicon, electroless nickel, GlidcopTM, aluminum, precipitation- hardening stainless steel, mild steel, invar and superinvar. Finally we summarize conclusions and propose ideas for further research.

  3. Synchrotron frequency spread independence of bunched-beam stochastic cooling at the Fermilab Recycler

    Directory of Open Access Journals (Sweden)

    D. Broemmelsiek

    2005-12-01

    Full Text Available It is generally accepted that longitudinal stochastic cooling of bunched beams is not possible without a synchrotron frequency spread. Experiments in the Fermilab Recycler storage ring demonstrate the opposite: with an antiproton bunch in a parabolic potential well (no synchrotron frequency spread, the cooling was almost as efficient as in a trapezoidal potential well (with a relative synchrotron frequency spread of ∼100%. A possible explanation is that, at Recycler parameters, diffusion processes are sufficient to provide particle mixing.

  4. Full-beam performances of a PET detector with synchrotron therapeutic proton beams

    Science.gov (United States)

    Piliero, M. A.; Pennazio, F.; Bisogni, M. G.; Camarlinghi, N.; Cerello, P. G.; Del Guerra, A.; Ferrero, V.; Fiorina, E.; Giraudo, G.; Morrocchi, M.; Peroni, C.; Pirrone, G.; Sportelli, G.; Wheadon, R.

    2016-12-01

    Treatment quality assessment is a crucial feature for both present and next-generation ion therapy facilities. Several approaches are being explored, based on prompt radiation emission or on PET signals by {β+} -decaying isotopes generated by beam interactions with the body. In-beam PET monitoring at synchrotron-based ion therapy facilities has already been performed, either based on inter-spill data only, to avoid the influence of the prompt radiation, or including both in-spill and inter-spill data. However, the PET images either suffer of poor statistics (inter-spill) or are more influenced by the background induced by prompt radiation (in-spill). Both those problems are expected to worsen for accelerators with improved duty cycle where the inter-spill interval is reduced to shorten the treatment time. With the aim of assessing the detector performance and developing techniques for background reduction, a test of an in-beam PET detector prototype was performed at the CNAO synchrotron-based ion therapy facility in full-beam acquisition modality. Data taken with proton beams impinging on PMMA phantoms showed the system acquisition capability and the resulting activity distribution, separately reconstructed for the in-spill and the inter-spill data. The coincidence time resolution for in-spill and inter-spill data shows a good agreement, with a slight deterioration during the spill. The data selection technique allows the identification and rejection of most of the background originated during the beam delivery. The activity range difference between two different proton beam energies (68 and 72 MeV) was measured and found to be in sub-millimeter agreement with the expected result. However, a slightly longer (2 mm) absolute profile length is obtained for in-spill data when compared to inter-spill data.

  5. The precision of respiratory-gated delivery of synchrotron-based pulsed beam proton therapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsunashima, Yoshikazu; Vedam, Sastry; Dong Lei; Balter, Peter; Mohan, Radhe [Department of Radiation Physics, Unit 94, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030 (United States); Umezawa, Masumi, E-mail: ytsunash@mdanderson.or [Accelerator System Group Medical System Project, Hitachi, Ltd, Energy and Environmental Systems Laboratory, 2-1, Omika-cho 7-chome, Hitachi-shi, Ibaraki-ken 319-1221 (Japan)

    2010-12-21

    A synchrotron-based proton therapy system operates in a low repetition rate pulsed beam delivery mode. Unlike cyclotron-based beam delivery, there is no guarantee that a synchrotron beam can be delivered effectively or precisely under the respiratory-gated mode. To evaluate the performance of gated synchrotron treatment, we simulated proton beam delivery in the synchrotron-based respiratory-gated mode using realistic patient breathing signals. Parameters used in the simulation were respiratory motion traces (70 traces from 24 patients), respiratory gate levels (10%, 20% and 30% duty cycles at the exhalation phase) and synchrotron magnet excitation cycles (T{sub cyc}) (fixed T{sub cyc} mode: 2.7, 3.0-6.0 s and each patient breathing cycle, and variable T{sub cyc} mode). The simulations were computed according to the breathing trace in which the proton beams were delivered. In the shorter fixed T{sub cyc} (<4 s), most of the proton beams were delivered uniformly to the target during the entire expiration phase of the respiratory cycle. In the longer fixed T{sub cyc} (>4 s) and the variable T{sub cyc} mode, the proton beams were not consistently delivered during the end-expiration phase of the respiratory cycle. However we found that the longer and variable T{sub cyc} operation modes delivered proton beams more precisely during irregular breathing.

  6. The radiation measurement applied to beam lifetime study on the synchrotron radiation facilities

    Science.gov (United States)

    Li, Yuxiong; Li, Juexin; Liu, Zuping; Cui, Yonggang; Gong, Guanghua; Shao, Beibei

    2003-06-01

    To collect beam loss information from an accelerator radiation field is helpful to machine study and operation. For a synchrotron radiation storage ring, shower electrons give a distinct clue to loss location and a BLM-XS model detector is suitable to detect them. Recently, we set up a new beam loss monitoring system by this method for National Synchrotron Radiation Laboratory (NSRL) storage ring. It does not interfere with the vacuum chamber and machine operation. Different from other systems, the detectors are used in pairs, fixed on opposite sides of the chamber separately. Some interesting phenomena about beam lifetime were observed. We located exactly where an excessive beam loss took place during ramping process and solved the problem. It was proved that gas accumulated at the front ends of photo-beam lines strongly impacted the electron beam and led to beam lifetime decreases. The cause of beam lifetime decrease because of superconducting wiggler is discussed.

  7. Preliminary studies of the quickly pulsed synchrotron involved in the Beta-Beam project; Etudes preliminaires du synchrotron rapidement pulse du projet Beta-Beam

    Energy Technology Data Exchange (ETDEWEB)

    Lachaize, A

    2007-07-01

    This study presents a quickly-pulsed synchrotron able to accelerate He{sup 6} and Ne{sup 18} beams from 100 MeV/u till 3.5 GeV (proton equivalent) The accelerator is made up of 48 bending dipoles and 42 focusing quadrupoles. The design of the HF accelerating system, the bunch injection and the correction of errors in beam dynamics are dealt with.

  8. Conditions for coherent-synchrotron-radiation-induced microbunching suppression in multibend beam transport or recirculation arcs

    OpenAIRE

    C.-Y. Tsai; Di Mitri, S.; Douglas, D; Li, R.; Tennant, C

    2017-01-01

    The coherent synchrotron radiation (CSR) of a high-brightness electron beam traversing a series of dipoles, such as transport or recirculation arcs, may result in beam phase space degradation. On one hand, CSR can perturb electron transverse motion in dispersive regions along the beam line and possibly cause emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching instability. For transport arcs, several schemes have been proposed to ...

  9. Throughput of ADSL modems

    NARCIS (Netherlands)

    Broersma, H.J.; Bruin, N.; Hurink, J.L.; Meester, L.E.; Op de Beek, S.S.; Westhuis, J.

    1999-01-01

    This paper considers the throughput of ADSL (Asymmetric Digital Subscriber Line) modems, used for high-speed data transmission over relatively unreliable connections, e.g. copper telephone wires. The modem technique uses an error correcting code and interleaving. The settings include a grouping fact

  10. On the polarized beam acceleration in medium energy synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.Y.

    1992-12-31

    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.

  11. Development and Optimisation of the SPS and LHC beam diagnostics based on Synchrotron Radiation monitors

    CERN Document Server

    AUTHOR|(CDS)2081364; Roncarolo, Federico

    Measuring the beam transverse emittance is fundamental in every accelerator, in particular for colliders, where its precise determination is essential to maximize the luminosity and thus the performance of the colliding beams.
 Synchrotron Radiation (SR) is a versatile tool for non-destructive beam diagnostics, since its characteristics are closely related to those of the source beam. At CERN, being the only available diagnostics at high beam intensity and energy, SR monitors are exploited as the proton beam size monitor of the two higher energy machines, the Super Proton Synchrotron (SPS) and the Large Hadron Collider (LHC). The thesis work documented in this report focused on the design, development, characterization and optimization of these beam size monitors. Such studies were based on a comprehensive set of theoretical calculations, numerical simulations and experiments. A powerful simulation tool has been developed combining conventional softwares for SR simulation and optics design, thus allowing t...

  12. A fast beam loss monitor system for the KEK proton synchrotron complex

    Science.gov (United States)

    Holt, J. A.; Kishiro, J.; Arakawa, D.; Hiramatsu, S.

    1991-06-01

    Efforts to increase the intensity of the KEK proton synchrotron have led to the need for a new fast response beam loss monitor system. The design and some prelimitary test results of a new beam loss monitor system are presented.(AIP)

  13. Performance of the HIMAC beam control system using multiple-energy synchrotron operation

    Science.gov (United States)

    Mizushima, K.; Furukawa, T.; Iwata, Y.; Hara, Y.; Saotome, N.; Saraya, Y.; Tansho, R.; Sato, S.; Fujimoto, T.; Shirai, T.; Noda, K.

    2017-09-01

    Multiple-energy synchrotron operation was developed to realize fast 3D scanning irradiation for carbon-ion radiotherapy. This type of operation can output various carbon-ion beams with different energies in a single synchrotron cycle. The beam control system used in this kind of operation was developed to quickly provide the beam energy and intensity required from the irradiation control system. The performance of the system was verified by experimental tests. The system could output beams of 197 different energies in 63 s. The beam intensity could be controlled for all the output beams without large ripples or overshooting. The experimental test of irradiation for prostate cancer treatment was also successfully performed, and the test results proved that our system can greatly reduce the irradiation time.

  14. Formation of a single-bunch beam in the booster synchrotron at SPring-8

    Science.gov (United States)

    Suzuki, Hiromitsu; Aoki, Tsuyoshi; Ego, Hiroyasu; Hara, Masahiro; Hosoda, Naoyasu; Kawashima, Yoshitaka; Ohashi, Yuji; Ohshima, Takashi; Tani, Norio; Yabashi, Makina; Yonehara, Hiroto

    2000-04-01

    In order to fill an radio frequency (rf) bucket with an electron beam in the storage ring at SPring-8, an rf knockout system was installed in the booster synchrotron. With this system, the energy of the electron beam injected from the linac was increased from 1 to 8 GeV. The time width of multi-bunch beams from the linac operated at 2856 MHz rf can be selected as 1 or 40 ns. The beam injected from the linac is distributed in rf buckets of the booster synchrotron operated at 508.58 MHz rf. To fill a single rf bucket with a beam, the rf knockout system is operated at a minimum beam energy of 1 GeV. By using the rf knockout system, the electron beam is effectively kept in a single rf bucket. Then the beam is injected into a targeted rf bucket in the storage ring with a precise timing system. The beam intensity of satellite rf buckets in the storage ring was measured with a photon counting method and determined to be 10 -6 less than that of the main rf bucket. In this paper, we describe the rf knockout system installed in the booster synchrotron.

  15. Refractive lenses as a beam diagnostics tool for high-energy synchrotron radiation

    CERN Document Server

    Weitkamp, T; Drakopoulos, M; Souvorov, A; Snigireva, I; Snigirev, A; Guenzler, F; Schrör, C; Lengeler, B

    2001-01-01

    Parabolic compound refractive lenses (CRLs) for hard X rays have been used to image the electron beam at undulator and bending-magnet beamlines at the ESRF. The measurements yield the shape and size of the synchrotron radiation source, and show that CRLs with paraboloid surface shape can be used as a beam diagnostics tool at high-energy electron storage rings. The optical resolution of the imaging setup can be as small as 4 mu m. This is smaller than typical values of the electron beam size in third-generation synchrotron sources. We report measurements at two ESRF beamlines and resolution calculations taking into account the properties of synchrotron radiation and the transmission characteristics of the CRLs used.

  16. Detailed Resolution Studies of the Synchrotron Radiation Profile Monitor for the HERA Electron Beam

    CERN Document Server

    Kube, G; Wittenburg, K

    2005-01-01

    The precise determination of the beam emittance is essential for the understanding of the luminosity in colliding beam experiments as the ones at the e-p storage ring HERA at DESY. For the measurement of the electron beam emittance a monitor is used which is based on the direct imaging of visible synchrotron radiation from a bending magnet. In order to reduce the thermal heating of the light extracting beryllium mirror it is moved away from the beam axis in vertical direction. While the resolution of profile measurements by synchrotron radiation is already strictly limited by fundamental effects, the observation in off-axis geometry modifies the intensity distribution additionally leading to an increased contribution of the diffraction limited resolution. In order to describe the resolution broadening effects detailed calculations have been performed with the computer code SRW. Taking into account the calculated corrections the deduced beam emittances are in good agreement with independent measurements from a...

  17. Separated high-energy electron beams using synchrotron radiation

    CERN Document Server

    Farley, F J M; Picasso, Emilio

    1972-01-01

    Electrons with kinetic energy in the 100 GeV range may be separated from other particles by using their energy-loss due to synchrotron radiation in a high-field magnet. In this paper the associated fluctuations in energy and angle are shown to be small enough for the method to be useful. Detailed design formulae are presented for several magnet configurations. (7 refs).

  18. Spatial and Temporal Beam Profiles for the LHC using Synchrotron Light

    CERN Document Server

    Jeff, A; Pedersen, S Bart; Rabiller, A; Bravin, E; Boccardi, A; Lefevre, T

    2010-01-01

    Synchrotron radiation is emitted whenever a beam of charged particles passes though a magnetic field. The power emitted is strongly dependent on the relativistic Lorentz factor of the particles, which itself is proportional to the beam energy and inversely proportional to the particle rest mass. Thus, synchrotron radiation is usually associated with electron accelerators, which are commonly used as light sources. However the largest proton machines reach sufficiently high energies to make synchrotron light useful for diagnostic purposes. The Large Hadron Collider at CERN will accelerate protons up to an energy of 7TeV. An optical arrangement has been made which focuses synchrotron light from two LHC magnets to image the cross-section of the beam. It is also planned to use this setup to produce a longitudinal profile of the beam by use of fast Single Photon Counting. This is complicated by the bunched nature of the beam which needs to be measured with a very large dynamic range. In this contribution we present...

  19. Simulation and optimization of beam losses during continuous transfer extraction at the CERN Proton Synchrotron

    CERN Document Server

    Garcia, J B

    2011-01-01

    The proton beams used for the fixed target physics at the Super Proton Synchrotron (SPS) are extracted from the Proton Synchrotron ( PS) by a multiturn technique called continuous transfer (CT). During the CT extraction, large losses are observed in locations where the machine aperture should be large enough to accommodate the circulating beam. This limits the maximum intensity deliverable due to the induced stray radiation outside the PS tunnel. Scattered particles from the interaction with the electrostatic septum are identified as the possible source of these losses. This article presents a detailed study aiming to understand the origin of losses and propose possible cures. The simulations could reproduce accurately the beam loss pattern measured in real machine operation and determine the beam shaving, intrinsic to the extraction process, as the cause for the unexpected losses. Since these losses are unavoidable, the proposed solution implies a new optics scheme displacing the losses to a region with bett...

  20. Coherence properties of focused X-ray beams at high brilliance synchrotron sources

    CERN Document Server

    Singer, A

    2013-01-01

    An analytical approach describing properties of focused partially coherent X-ray beams is presented. The method is based on the results of statistical optics and gives both the beam size and transverse coherence length at any distance behind an optical element. In particular, here we consider Gaussian Schell-model beams and thin optical elements. Limiting cases of incoherent and fully coherent illumination of the focusing element are discussed. The effect of the beam defining aperture, typically used in combination with focusing elements at synchrotron sources to improve transverse coherence, is also analyzed in detail. As an example the coherence properties in the focal region of compound refractive lenses at the PETRA III synchrotron source are analyzed.

  1. A Tool for Longitudinal Beam Dynamics in Synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Ostiguy, J.-F. [Fermilab; Lebedev, V. A. [Fermilab

    2017-05-01

    A number of codes are available to simulate longitudinal dynamics in synchrotrons. Some established ones include TIBETAN, LONG1D, ESME and ORBIT. While they embody a wealth of accumulated wisdom and experience, most of these codes were written decades ago and to some extent they reflect the constraints of their time. As a result, there is an interest for updated tools taking better advantage of modern software and hardware capabilities. At Fermilab, the PIP-II project has provided the impetus for development of such a tool. In this contribution, we discuss design decisions and code architecture. A selection of test cases based on an initial prototype are also presented.

  2. Dislocation structures in tetragonal hen egg-white lysozyme crystals using synchrotron white-beam topography

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, H. [Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan)], E-mail: h_koizumi@imr.tohoku.ac.jp; Tachibana, M.; Kojima, K. [International Graduate School of Arts and Sciences, Yokohama City University, Yokohama 236-0027 (Japan); Yonenaga, I. [Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan)

    2007-12-15

    We clearly observed the dislocation of protein crystals by means of synchrotron white-beam topography. According to the invisibility criterion (g.b=0) of dislocation images, it was found that the predominant dislocations are of screw character with Burgers vector b=<110>. These results are discussed in terms of elastic energy of dislocations.

  3. Formation of a single-bunch beam in the booster synchrotron at SPring-8

    CERN Document Server

    Suzuki, H; Ego, H; Hara, M; Hosoda, N; Kawashima, Y; Ohashi, Y; Ohshima, T; Tani, N; Yabashi, M; Yonehara, H

    2000-01-01

    In order to fill a radio frequency (rf) bucket with an electron beam in the storage ring at SPring-8, an rf knockout system was installed in the booster synchrotron. With this system, the energy of the electron beam injected from the linac was increased from 1 to 8 GeV. The time width of multi-bunch beams from the linac operated at 2856 MHz rf can be selected as 1 or 40 ns. The beam injected from the linac is distributed in rf buckets of the booster synchrotron operated at 508.58 MHz rf. To fill a single rf bucket with a beam, the rf knockout system is operated at a minimum beam energy of 1 GeV. By using the rf knockout system, the electron beam is effectively kept in a single rf bucket. Then the beam is injected into a targeted rf bucket in the storage ring with a precise timing system. The beam intensity of satellite rf buckets in the storage ring was measured with a photon counting method and determined to be 10 sup - sup 6 less than that of the main rf bucket. In this paper, we describe the rf knockout sy...

  4. Beam studies at the SPEAR3 synchrotron using a digital optical mask

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H.D., E-mail: hao.zhang@cockcroft.ac.uk [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Cockcroft Institute, Daresbury Sci Tech, Warrington WA4 4AD (United Kingdom); Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Fiorito, R.B. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Cockcroft Institute, Daresbury Sci Tech, Warrington WA4 4AD (United Kingdom); Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Corbett, J. [SLAC, Menlo Park, CA 94650 (United States); Shkvarunets, A.G. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Tian, K.; Fisher, A. [SLAC, Menlo Park, CA 94650 (United States)

    2016-05-01

    The 3GeV SPEAR3 synchrotron light source operates in top-up injection mode with up to 500 mA circulating in the storage ring (equivalently 392 nC). Each injection pulse contains 40–80 pC producing a contrast ratio between total stored charge and injected charge of about 6500:1. In order to study transient injected beam dynamics during user operations, it is desirable to optically image the injected pulse in the presence of the bright stored beam. In the present work this is done by imaging the visible component of the synchrotron radiation onto a digital micro-mirror-array device (DMD), which is then used as an optical mask to block out light from the bright central core of the stored beam. The physical masking, together with an asynchronously-gated, ICCD imaging camera, makes it possible to observe the weak injected beam component on a turn-by-turn basis. The DMD optical masking system works similar to a classical solar coronagraph but has some distinct practical advantages: i.e. rapid adaption to changes in the shape of the stored beam, a high extinction ratio for unwanted light and minimum scattering from the primary beam into the secondary optics. In this paper we describe the DMD masking method, features of the high dynamic range point spread function for the SPEAR3 optical beam line and measurements of the injected beam in the presence of the stored beam.

  5. Beaming of particles and synchrotron radiation in relativistic magnetic reconnection

    CERN Document Server

    Kagan, Daniel; Piran, Tsvi

    2016-01-01

    Relativistic reconnection has been invoked as a mechanism for particle acceleration in numerous astrophysical systems. According to idealised analytical models reconnection produces a bulk relativistic outflow emerging from the reconnection sites (X-points). The resulting radiation is therefore highly beamed. Using two-dimensional particle-in-cell (PIC) simulations, we investigate particle and radiation beaming, finding a very different picture. Instead of having a relativistic average bulk motion with isotropic electron velocity distribution in its rest frame, we find that the bulk motion of particles in X-points is similar to their Lorentz factor gamma, and the particles are beamed within about 5/gamma. On the way from the X-point to the magnetic islands, particles turn in the magnetic field, forming a fan confined to the current sheet. Once they reach the islands they isotropise after completing a full Larmor gyration and their radiation is not strongly beamed anymore. The radiation pattern at a given freq...

  6. Experimental studies on coherent synchrotron radiation at an emittance exchange beam line

    Directory of Open Access Journals (Sweden)

    J. C. T. Thangaraj

    2012-11-01

    Full Text Available One of the goals of the Fermilab A0 photoinjector is to investigate experimentally the transverse to longitudinal emittance exchange (EEX principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy-chirped beam.

  7. A Monitor and Control System for the Synchrotron Radiation Beam Lines at DAΦNE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Three synchrotron radiation beam lines have been built on DAΦNE,the Frascati electron-positron accelerator.It is Possible to monitor and control all the elements on the beam lines using a modular network distributed I/O system by National Instrunments (FieldPoint) with Bridge VIEW/Lab VIEW programs,Two of these beam lines have radiation safety problems solved by two independent and redundant systems,using mechanical switches ,and S7-200 PLC's by Siemens.In this article our solution will be described in details.

  8. VT Cable Modem Systems 2013

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2013) includes lines depicting the extent of Vermont's cable modem broadband system as of 6/30/2013. This data...

  9. VT Cable Modem Systems 2005

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2005) includes lines depicting the extent of Vermont's cable modem broadband system as of 12/31/2005. This...

  10. Absolute x-ray dosimetry on a synchrotron medical beam line with a graphite calorimeter.

    Science.gov (United States)

    Harty, P D; Lye, J E; Ramanathan, G; Butler, D J; Hall, C J; Stevenson, A W; Johnston, P N

    2014-05-01

    The absolute dose rate of the Imaging and Medical Beamline (IMBL) on the Australian Synchrotron was measured with a graphite calorimeter. The calorimetry results were compared to measurements from the existing free-air chamber, to provide a robust determination of the absolute dose in the synchrotron beam and provide confidence in the first implementation of a graphite calorimeter on a synchrotron medical beam line. The graphite calorimeter has a core which rises in temperature when irradiated by the beam. A collimated x-ray beam from the synchrotron with well-defined edges was used to partially irradiate the core. Two filtration sets were used, one corresponding to an average beam energy of about 80 keV, with dose rate about 50 Gy/s, and the second filtration set corresponding to average beam energy of 90 keV, with dose rate about 20 Gy/s. The temperature rise from this beam was measured by a calibrated thermistor embedded in the core which was then converted to absorbed dose to graphite by multiplying the rise in temperature by the specific heat capacity for graphite and the ratio of cross-sectional areas of the core and beam. Conversion of the measured absorbed dose to graphite to absorbed dose to water was achieved using Monte Carlo calculations with the EGSnrc code. The air kerma measurements from the free-air chamber were converted to absorbed dose to water using the AAPM TG-61 protocol. Absolute measurements of the IMBL dose rate were made using the graphite calorimeter and compared to measurements with the free-air chamber. The measurements were at three different depths in graphite and two different filtrations. The calorimetry measurements at depths in graphite show agreement within 1% with free-air chamber measurements, when converted to absorbed dose to water. The calorimetry at the surface and free-air chamber results show agreement of order 3% when converted to absorbed dose to water. The combined standard uncertainty is 3.9%. The good agreement of

  11. Development of the Beam Diagnostics System for the J-PARC Rapid-Cycling Synchrotron

    CERN Document Server

    Hayashi, Naoki; Hiroki, Seiji; Kishiro, Junichi; Lee, Seishu; Miura, Takako; Teruyama, Yuzou; Toyama, Takeshi; Toyokawa, Ryoji

    2005-01-01

    Development of the beam diagnostics system for the J-PARC (Japan Proton Accelerator Research Complex) Rapid-Cycling Synchrotron is described. The system consists of Beam Position Monitor (BPM), Beam Loss Monitor (BLM), Current monitors (DCCT, SCT, MCT, FCT, WCM), Tune meter system, 324MHz-BPM, Profile monitor, and Halo monitor. BPM electrode is electro-static type and its electronics is designed for both COD and turn-by-turn measurements. Five current monitors have different time constants in order to cover wide frequency range. The tune meter is consisted of RFKO and the beam pick-up electrode. For the continuous injected beam monitoring, 324MHz-BPM detects Linac frequency. Two types of profile monitor are multi-wire for low intensity tuning and the residual gas monitor for non-destructive measurement.

  12. Tomography and imaging at the PSICHE beam line of the SOLEIL synchrotron

    Science.gov (United States)

    King, A.; Guignot, N.; Zerbino, P.; Boulard, E.; Desjardins, K.; Bordessoule, M.; Leclerq, N.; Le, S.; Renaud, G.; Cerato, M.; Bornert, M.; Lenoir, N.; Delzon, S.; Perrillat, J.-P.; Legodec, Y.; Itié, J.-P.

    2016-09-01

    PSICHE (Pressure, Structure and Imaging by Contrast at High Energy) is the high-energy beam line of the SOLEIL synchrotron. The beam line is designed to study samples at extreme pressures, using diffraction, and to perform imaging and tomography for materials science and other diverse applications. This paper presents the tomograph and the use of the beam line for imaging, with emphasis on developments made with respect to existing instruments. Of particular note are the high load capacity rotation stage with free central aperture for installing large or complex samples and sample environments, x-ray mirror and filter optics for pink beam imaging, and multiple options for combining imaging and diffraction measurement. We describe how x-ray imaging techniques have been integrated into high-pressure experiments. The design and the specifications of the beam line are described, and several case studies drawn from the first user experiments are presented.

  13. An inexpensive spectroscopic beam monitor for hard X-ray synchrotron applications

    CERN Document Server

    Owens, A; Den Hartog, R; Quarati, F; Webb, A; Welter, E; HASYLAB at DESY, Hamburg, Germany

    2007-01-01

    We describe an inexpensive beam monitor for hard X-ray synchrotron applications which has good spectroscopic abilities and can operate without cooling. The device is centred on an inexpensive, commercial off-the-shelf, large area (1.2 × 1.2 mm2) Si photodiode operated in single counting mode. Measurements carried out at the HASYLAB synchrotron research facility have shown that it is fully spectroscopic across the energy range 8 keV to 100 keV with a measured energy resolution of ~ 1.2 keV FWHM at room temperature. The measured resolutions were found to be the same under pencil-beam and full-area illumination, indicating uniform crystallinity and stoichiometry of the bulk. The low cost, simplicity and performance of the detector make it suitable for a wider range of applications, e.g., in undergraduate laboratory experiments.

  14. National Synchrotron Light Source users manual: Guide to the VUV and x-ray beam lines

    Energy Technology Data Exchange (ETDEWEB)

    Gmuer, N.F.; White-DePace, S.M. (eds.)

    1987-08-01

    The success of the National Synchrotron Light Source in the years to come will be based, in large part, on the size of the users community and the diversity of the scientific disciplines represented by these users. In order to promote this philosophy, this National Synchrotron Light Source (NSLS) Users Manual: Guide to the VUV and X-Ray Beam Lines, has been published. This manual serves a number of purposes. In an effort to attract new research, it will present to the scientific community-at-large the current and projected architecture and capabilities of the various VUV and x-ray beam lines and storage rings. We anticipate that this publication will be updated periodically in order to keep pace with the constant changes at the NSLS.

  15. Visible-light beam size monitors using synchrotron radiation at CESR

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.T., E-mail: sw565@cornell.edu [Cornell Laboratory for Accelerator-Based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Rubin, D.L.; Conway, J.; Palmer, M.; Hartill, D. [Cornell Laboratory for Accelerator-Based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Campbell, R.; Holtzapple, R. [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States)

    2013-03-01

    A beam profile monitor utilizing visible synchrotron radiation (SR) from a bending magnet has been designed and installed in Cornell Electron-Positron Storage Ring (CESR). The monitor employs a double-slit interferometer to measure both the horizontal and vertical beam sizes over a wide range of beam currents. By varying the separation of the slits, beam sizes ranging from 50 to 500 μm can be measured with a resolution of approximately 5 μm. To measure larger beam size (>500 μm), direct imaging can be employed by rotating the double slits away from SR beam path. By imaging the π-polarized component of SR, a small vertical beam size (∼70 μm) was measured during an undulator test run in CESR, which was consistent with the interferometer measurement. To measure the bunch length, a beam splitter is inserted to direct a fraction of light into a streak camera setup. This beam size monitor measures the transverse and longitudinal beam sizes simultaneously, which is successfully used for intrabeam scattering studies. Detailed error analysis is discussed.

  16. Growth Defects in Langasite Crystals Observed with White Beam Synchrotron Radiation Topography

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Langasite single crystal was grown by the Czochralski method and its perfection was assessed by white beam synchrotron radiation topography. It is found that the growth core and the growth striations are the primary growth defects and they show strong X-ray kinematical contrast in the topographs. Another typical defect in LGS crystal is dislocation. The formation mechanisms of these growth defects in LGS crystals were discussed.

  17. Test of Different Beam Loss Detectors at the GSI Heavy Ion Synchrotron

    CERN Document Server

    Forck, P

    2001-01-01

    For the sensitive process of slow extraction from a synchrotron a reliable control of the beam losses is needed. We have tested several types of particle detectors mounted at the extraction path of the SIS: A BF-tube for pure neutron detection, a liquid and a plastic scintillator detecting neutrons, gammas and charged particles and an Argon filled ionization chamber mainly sensitive to charged particles. While the count rate is quite different, the time evolution of all detector signals during the spill are similar, but the plastic scintillator has the highest dynamic range. This type is going to be used for beam alignment.

  18. Use of XR-QA2 radiochromic films for quantitative imaging of a synchrotron radiation beam

    Science.gov (United States)

    Di Lillo, F.; Dreossi, D.; Emiro, F.; Fedon, C.; Longo, R.; Mettivier, G.; Rigon, L.; Russo, P.; Tromba, G.

    2015-05-01

    In the framework of an ongoing project, promoted by INFN, at the SYRMEP beamline of the ELETTRA synchrotron radiation facility (Trieste, Italy) for phase-contrast breast X-ray computed tomography, the assessment of the dose to the breast is one of the issues, requiring the determination of the distribution of X-ray incident photon fluence. This work investigates the use of XR-QA2 radiochromic films for quantitative imaging of the synchrotron radiation (SR) beam. XR-QA2 films were irradiated in a plane transverse to the beam axis, with a monochromatic beam of energy of 28, 35, 38 or 40 keV. The response of the radiochromic film was calibrated in terms of average air kerma measured with an ionization chamber. The net reflectance of the exposed film was then converted to photon fluence per unit air kerma (mm-2mGy-1). The SR beam profile was acquired also with a scintillator (GOS) based, fiber optic coupled CCD camera as well as with a scintillator based flat panel detector. Horizontal and vertical line profiles acquired with the radiochromic films show the 2D distribution of the beam intensity, with variations in the order of 15-20% in the horizontal direction. The response of the radiochromic film is comparable to that of the other imaging detectors, within less than 5% variation.

  19. Development of a synchrotron radiation beam monitor for the Integrable Optics Test Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Scarpelli, Andrea [Univ. of Ferrara (Italy)

    2016-01-01

    Nonlinear integrable optics applied to beam dynamics may mitigate multi-particle instabilities, but proof of principle experiments have never been carried out. The Integrable Optics Test Accelerator (IOTA) is an electron and proton storage ring currently being built at Fermilab, which addresses tests of nonlinear lattice elements in a real machine in addition to experiments on optical stochastic cooling and on the single-electron wave function. These experiments require an outstanding control over the lattice parameters, achievable with fast and precise beam monitoring systems. This work describes the steps for designing and building a beam monitor for IOTA based on synchrotron radiation, able to measure intensity, position and transverse cross-section beam.

  20. Electromagnetic Coupling Between High Intensity LHC Beams and the Synchrotron Radiation Monitor Light Extraction System

    CERN Document Server

    Andreazza, W; Bravin, E; Caspers, F; Garlasch`e, M; Gras, J; Goldblatt, A; Lefevre, T; Jones, R; Metral, E; Nosych, A; Roncarolo_, F; Salvant, B; Trad, G; Veness, R; Vollinger, C; Wendt, M

    2013-01-01

    The CERN LHC is equipped with two Synchrotron Radiation Monitor (BSRT) systems used to characterise transverse and longitudinal beam distributions. Since the end of the 2011 LHC run the light extraction system, based on a retractable mirror, has suffered deformation and mechanical failure that is correlated to the increase in beam intensity. Temperature probes have associated these observations to a strong heating of the mirror support with a dependence on the longitudinal bunch length and shape, indicating the origin as electromagnetic coupling between the beam and the structure. This paper combines all this information with the aim of characterising and improving the system in view of its upgrade during the current LHC shutdown. Beam-based observations are presented along with electromagnetic and thermomechanical simulations and complemented by laboratory measurements, including the study of the RF properties of different mirror bulk and coating materials.

  1. Control of Coherent Synchrotron Radiation and Micro-Bunching Effects During Transport of High Brightness Electron Beams

    CERN Document Server

    Douglas, D R; Hutton, A; Krafft, G A; Li, R; Neil, G R; Roblin, Y; Tennant, C D; Tsai, C -Y

    2014-01-01

    Beam quality preservation during transport of high-brightness electron beams is of general concern in the design of modern accelerators. Methods to manage incoherent synchrotron radiation (ISR) have been in place for decades; as beam brightness has improved coherent synchrotron radiation (CSR) and the microbunching instability (uBI) have emerged as performance limitations. We apply the compensation analysis of diMitri, Cornacchia, and Spampinati - as previously used by Borland - to the design of transport systems for use with low-emittance beams, and find that appropriately configured second order achromats will suppress transverse emittance growth due to CSR and appear to limit uBI gain.

  2. Passive beam sprending systems and light-weight gentries for synchrotron based hadron therapy

    CERN Document Server

    Maier, A T

    1998-01-01

    Hadron therapy is a promising technique that uses beams of protons or light ions for the treatment of cancer. In order to open this technique to a wider application, hospital based treatment centres are now needed. The extbf{P}roton- extbf{I}on extbf{M}edical extbf{M}achine extbf{S}tudy (PIMMS) in CERN is concerned with the design of such a centre that would use both protons and light ions. The dual species operation makes it preferable to base the centre on a synchrotron. The present thesis is concerned with the beam delivery for the protons. After introducing the basic vocabulary of linear beam optics, the feasibility of a light-weight gantry with passive beam spreading fed by a synchrotron is investigated. The device is a non-linear magnetic structure, which can be described as a emph{magnetic guide} or as a emph{proton pipe}. Detailed studies show that while it is possible to design an optically stable 270$^circ$ section, which would be necessary for a gantry, the properties do not fulfil the requirements...

  3. A polarimeter for GeV protons of recirculating synchrotron beams

    CERN Document Server

    Bauer, F

    1999-01-01

    A polarimeter for use in recirculating beams of proton synchrotrons with energies from 300 MeV up to several GeV has been developed. The polarimetry is based on the asymmetry measurement of elastic p->p scattering on an internal CH sub 2 fiber target. The forward going protons are detected with two scintillator systems on either side of the beam pipe close to the angle THETA sub f of maximum analyzing power A sub N. Each one operates in coincidence with a broad (DELTA THETA sub b =21.4 deg. ), segmented detector system for the recoil proton of kinematically varying direction THETA sub b; this position resolution is also used for a concurrent measurement of the p->C and nonelastic p->p background. The CH sub 2 fiber can be replaced by a carbon fiber for detailed background studies; 'false' asymmetries are accounted for with a rotation of the polarimeter around the beam axis. Polarimetry has been performed in the internal beam of the Cooler Synchrotron COSY at fixed energies as well as during proton acceleratio...

  4. Parasitic slow extraction of extremely weak beam from a high-intensity proton rapid cycling synchrotron

    Science.gov (United States)

    Zou, Ye; Tang, Jingyu; Yang, Zheng; Jing, Hantao

    2014-02-01

    This paper proposes a novel method to extract extremely weak beam from a high-intensity proton rapid cycling synchrotron (RCS) in the parasitic mode, while maintaining the normal fast extraction. The usual slow extraction method from a synchrotron by employing third-order resonance cannot be applied in a high-intensity RCS due to a very short flat-top at the extraction energy and the strict control on beam loss. The proposed parasitic slow extraction method moves the beam to scrape a scattering foil prior to the fast beam extraction by employing either a local orbit bump or momentum deviation or their combination, so that the halo part of the beam will be scattered. A part of the scattered particles will be extracted from the RCS and guided to the experimental area. The slow extraction process can last about a few milliseconds before the beam is extracted by the fast extraction system. The method has been applied to the RCS of China Spallation Neutron Source. With 1.6 GeV in the extraction energy, 62.5 μA in the average current and 25 Hz in the repetition rate for the RCS, the proton intensity by the slow extraction method can be up to 2×104 protons per cycle or 5×105 protons per second. The extracted beam has also a good time structure of approximately uniform in a spill which is required for many applications such as detector tests. Detailed studies including the scattering effect in the foil, the local orbit bump by the bump magnets and dispersive orbit bump by modifying the RF pattern, the multi-particle simulations by ORBIT and TURTLE codes, and some technical features for the extraction magnets are presented.

  5. 1-MW Beam Operation Scenario of the J-PARC 3-GeV Rapid Cycling Synchrotron

    Science.gov (United States)

    Hotchi, Hideaki

    The J-PARC 3-GeV Rapid Cycling Synchrotron initiates the final stage of beam commissioning aiming for the design output beam power of 1 MW from Oct. 2014 after completing the injector linac upgrade. In this paper, emittance growth and beam loss issues for the coming 1-MW beam operation will be discussed together with their possible mitigation scenarios, based on numerical simulations.

  6. Statistical signal processing techniques for coherent transversal beam dynamics in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Alhumaidi, Mouhammad

    2015-03-04

    Transversal coherent beam oscillations can occur in synchrotrons directly after injection due to errors in position and angle, which stem from inaccurate injection kicker reactions. Furthermore, the demand for higher beam intensities is always increasing in particle accelerators. The wake fields generated by the traveling particles will be increased by increasing the beam intensity. This leads to a stronger interaction between the beam and the different accelerator components, which increases the potential of coherent instabilities. Thus, undesired beam oscillations will occur when the natural damping is not enough to attenuate the oscillations generated by the coherent beam-accelerator interactions. The instabilities and oscillations can be either in transversal or longitudinal direction. In this work we are concerned with transversal beam oscillations only. In normal operation, transversal beam oscillations are undesired since they lead to beam quality deterioration and emittance blow up caused by the decoherence of the oscillating beam. This decoherence is caused by the tune spread of the beam particles. The emittance blow up reduces the luminosity of the beam, and thus the collision quality. Therefore, beam oscillations must be suppressed in order to maintain high beam quality during acceleration. A powerful way to mitigate coherent instabilities is to employ a feedback system. A Transversal Feedback System (TFS) senses instabilities of the beam by means of Pickups (PUs), and acts back on the beam through actuators, called kickers. In this thesis, a novel concept to use multiple PUs for estimating the beam displacement at the position with 90 phase advance before the kicker is proposed. The estimated values should be the driving feedback signal. The signals from the different PUs are delayed such that they correspond to the same bunch. Subsequently, a weighted sum of the delayed signals is suggested as an estimator of the feedback correction signal. The

  7. High precision beam momentum determination in a synchrotron using a spin resonance method

    CERN Document Server

    Goslawski, P; Gebel, R; Hartmann, M; Kacharava, A; Lehrach, A; Lorentz, B; Maier, R; Mielke, M; Papenbrock, M; Prasuhn, D; Stassen, R; Stein, H J; Stockhorst, H; Ströher, H; Wilkin, C

    2009-01-01

    In order to measure the mass of the eta meson with high accuracy using the d+p -> 3He+eta reaction, the momentum of the circulating deuteron beam in the Cooler Synchrotron COSY of the Forschungszentrum Juelich has to be determined with unprecedented precision. This has been achieved by studying the spin dynamics of the polarized deuteron beam. By depolarizing the beam through the use of an artificially induced spin resonance, it was possible to evaluate its momentum p with a precision of dp/p < 10-4 for a momentum of roughly 3 GeV/c. Different possible sources of error in the application of the spin resonance method are discussed in detail and its possible use during a standard experiment is considered.

  8. Very small beam-size measurement by a reflective synchrotron radiation interferometer

    Directory of Open Access Journals (Sweden)

    T. Naito

    2006-12-01

    Full Text Available A synchrotron radiation (SR interferometer with Herschelian reflective optics has been developed for the measurement of beams of several μm in size. In a conventional refractive SR interferometer, the dispersion effect of the objective lens limits the instrument to a smaller range of beam-size measurements. To avoid this problem, we designed a Herschelian arrangement of reflective optics for the interferometer. The effectiveness of the reflective SR interferometer was confirmed at the KEK Accelerator Test Facility (ATF damping ring. The measured vertical beam size obtained using the reflective SR interferometer was 4.7   μm and the estimated vertical emittance was 0.97×10^{-11}   m.

  9. Subacute neuropathological effects of microplanar beams of x-rays from a synchrotron wiggler.

    Science.gov (United States)

    Slatkin, D N; Spanne, P; Dilmanian, F A; Gebbers, J O; Laissue, J A

    1995-09-12

    Microplanar beam radiation therapy has been proposed to treat brain tumors by using a series of rapid exposures to an array of parallel x-ray beams, each beam having uniform microscopic thickness and macroscopic breadth (i.e., microplanar). Thirty-six rats were exposed head-on either to an upright 4-mm-high, 20- or 37-microns-wide beam or to a horizontal 7-mm-wide, 42-microns-high beam of mostly 32- to 126-keV, minimally divergent x-rays from the X17 wiggler at the National Synchrotron Light Source at Brookhaven National Laboratory. Parallel slices of the head, separated at either 75 or 200 microns on center, were exposed sequentially at 310-650 grays (Gy) per second until each skin-entrance absorbed dose reached 312, 625, 1250, 2500, 5000, or 10,000 Gy. The rats were euthanized 2 weeks or 1 month later. Two rats with 10,000-Gy-entrance slices developed brain tissue necrosis. All the other 10,000- and 5000-Gy-entrance slices and some of the 2500- and 1250-Gy-entrance slices showed loss of neuronal and astrocytic nuclei and their perikarya. No other kind of brain damage was evident histologically in any rat with entrance absorbed doses beam radiation therapy for brain tumors.

  10. A portable molecular beam epitaxy system for in situ x-ray investigations at synchrotron beamlines.

    Science.gov (United States)

    Slobodskyy, T; Schroth, P; Grigoriev, D; Minkevich, A A; Hu, D Z; Schaadt, D M; Baumbach, T

    2012-10-01

    A portable synchrotron molecular beam epitaxy (MBE) system is designed and applied for in situ investigations. The growth chamber is equipped with all the standard MBE components such as effusion cells with shutters, main shutter, cooling shroud, manipulator, reflection high energy electron diffraction setup, and pressure gauges. The characteristic feature of the system is the beryllium windows which are used for in situ x-ray measurements. An UHV sample transfer case allows in vacuo transfer of samples prepared elsewhere. We describe the system design and demonstrate its performance by investigating the annealing process of buried InGaAs self-organized quantum dots.

  11. Conditions for coherent-synchrotron-radiation-induced microbunching suppression in multibend beam transport or recirculation arcs

    Science.gov (United States)

    Tsai, C.-Y.; Di Mitri, S.; Douglas, D.; Li, R.; Tennant, C.

    2017-02-01

    The coherent synchrotron radiation (CSR) of a high-brightness electron beam traversing a series of dipoles, such as transport or recirculation arcs, may result in beam phase space degradation. On one hand, CSR can perturb electron transverse motion in dispersive regions along the beam line and possibly cause emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching instability. For transport arcs, several schemes have been proposed to suppress the CSR-induced emittance growth. Correspondingly, a few scenarios have been introduced to suppress CSR-induced microbunching instability, which however mostly aim for linac-based machines. In this paper we provide sufficient conditions for suppression of CSR-induced microbunching instability along transport or recirculation arcs. Examples are presented with the relevant microbunching analyses carried out by our developed semianalytical Vlasov solver [C.-Y. Tsai, D. Douglas, R. Li, and C. Tennant, Linear microbunching analysis for recirculation machines, Phys. Rev. ST Accel. Beams 19, 114401 (2016), 10.1103/PhysRevAccelBeams.19.114401]. The example lattices include low-energy (˜100 MeV ) and high-energy (˜1 GeV ) recirculation arcs, and medium-energy compressor arcs. Our studies show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. Beam current dependences of maximal CSR microbunching gains are also demonstrated, which should help outline a beam line design for different scales of nominal currents. We expect this analysis can shed light on the lattice design approach that aims to control the CSR-induced microbunching.

  12. Conditions for coherent-synchrotron-radiation-induced microbunching suppression in multibend beam transport or recirculation arcs

    Directory of Open Access Journals (Sweden)

    C.-Y. Tsai

    2017-02-01

    Full Text Available The coherent synchrotron radiation (CSR of a high-brightness electron beam traversing a series of dipoles, such as transport or recirculation arcs, may result in beam phase space degradation. On one hand, CSR can perturb electron transverse motion in dispersive regions along the beam line and possibly cause emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching instability. For transport arcs, several schemes have been proposed to suppress the CSR-induced emittance growth. Correspondingly, a few scenarios have been introduced to suppress CSR-induced microbunching instability, which however mostly aim for linac-based machines. In this paper we provide sufficient conditions for suppression of CSR-induced microbunching instability along transport or recirculation arcs. Examples are presented with the relevant microbunching analyses carried out by our developed semianalytical Vlasov solver [C.-Y. Tsai, D. Douglas, R. Li, and C. Tennant, Linear microbunching analysis for recirculation machines, Phys. Rev. ST Accel. Beams 19, 114401 (2016PRABFM1098-440210.1103/PhysRevAccelBeams.19.114401]. The example lattices include low-energy (∼100  MeV and high-energy (∼1  GeV recirculation arcs, and medium-energy compressor arcs. Our studies show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. Beam current dependences of maximal CSR microbunching gains are also demonstrated, which should help outline a beam line design for different scales of nominal currents. We expect this analysis can shed light on the lattice design approach that aims to control the CSR-induced microbunching.

  13. Beam diagnostic developments at the cooler synchrotron COSY-Jülich

    Indian Academy of Sciences (India)

    J Dietrich; I Mohos

    2002-12-01

    New developments of beam diagnostic devices and methods at the cooler synchrotron and storage ring COSY at the Forschungszentrum J¨ulich are described. A Schottky-pickup was tested and installed. The new pickup consists of four diagonally arranged plates which can be combined by means of relays to measure either in the horizontal or in the vertical plane. A new method for resonant tuning of the Schottky-pickup for transversal measurements was realized. A tune meter was developed for real-time tune measurements in the acceleration ramp and is used as routine diagnostic tool. Based on the developed bunch synchronous tracking generator an on-line phase space measurement was realized. For beam profile measurements a residual-gas ionization beam profile monitor was installed in the COSY-ring and tested. To measure the beam quality in case of fast and slow extraction a universal spill detector was developed and tested in the extraction beam line.

  14. Design of x-ray diagnostic beam line for a synchrotron radiation source and measurement results

    Science.gov (United States)

    Garg, Akash Deep; Karnewar, A. K.; Ojha, A.; Shrivastava, B. B.; Holikatti, A. C.; Puntambekar, T. A.; Navathe, C. P.

    2014-08-01

    Indus-2 is a 2.5 GeV synchrotron radiation source (SRS) operational at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We have designed, developed and commissioned x-ray diagnostic beam line (X-DBL) at the Indus-2. It is based on pinhole array imaging (8-18 keV). We have derived new equations for online measurements of source position and emission angle with pinhole array optics. Measured values are compared with the measurements at an independent x-ray beam position monitor (staggered pair blade monitor) installed in the X-DBL. The measured values are close to the theoretical expected values within ±12 μm (or ±1.5 μrad) for sufficiently wide range of the beam movements. So, beside the beam size and the beam emittance, online information for the vertical position and angle is also used in the orbit steering. In this paper, the various design considerations of the X-DBL and online measurement results are presented.

  15. Transverse beam splitting made operational: Key features of the multiturn extraction at the CERN Proton Synchrotron

    Directory of Open Access Journals (Sweden)

    A. Huschauer

    2017-06-01

    Full Text Available Following a successful commissioning period, the multiturn extraction (MTE at the CERN Proton Synchrotron (PS has been applied for the fixed-target physics programme at the Super Proton Synchrotron (SPS since September 2015. This exceptional extraction technique was proposed to replace the long-serving continuous transfer (CT extraction, which has the drawback of inducing high activation in the ring. MTE exploits the principles of nonlinear beam dynamics to perform loss-free beam splitting in the horizontal phase space. Over multiple turns, the resulting beamlets are then transferred to the downstream accelerator. The operational deployment of MTE was rendered possible by the full understanding and mitigation of different hardware limitations and by redesigning the extraction trajectories and nonlinear optics, which was required due to the installation of a dummy septum to reduce the activation of the magnetic extraction septum. This paper focuses on these key features including the use of the transverse damper and the septum shadowing, which allowed a transition from the MTE study to a mature operational extraction scheme.

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

    Science.gov (United States)

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

    2014-02-01

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

  17. Statistical signal processing techniques for coherent transversal beam dynamics in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Alhumaidi, Mouhammad

    2015-03-04

    Transversal coherent beam oscillations can occur in synchrotrons directly after injection due to errors in position and angle, which stem from inaccurate injection kicker reactions. Furthermore, the demand for higher beam intensities is always increasing in particle accelerators. The wake fields generated by the traveling particles will be increased by increasing the beam intensity. This leads to a stronger interaction between the beam and the different accelerator components, which increases the potential of coherent instabilities. Thus, undesired beam oscillations will occur when the natural damping is not enough to attenuate the oscillations generated by the coherent beam-accelerator interactions. The instabilities and oscillations can be either in transversal or longitudinal direction. In this work we are concerned with transversal beam oscillations only. In normal operation, transversal beam oscillations are undesired since they lead to beam quality deterioration and emittance blow up caused by the decoherence of the oscillating beam. This decoherence is caused by the tune spread of the beam particles. The emittance blow up reduces the luminosity of the beam, and thus the collision quality. Therefore, beam oscillations must be suppressed in order to maintain high beam quality during acceleration. A powerful way to mitigate coherent instabilities is to employ a feedback system. A Transversal Feedback System (TFS) senses instabilities of the beam by means of Pickups (PUs), and acts back on the beam through actuators, called kickers. In this thesis, a novel concept to use multiple PUs for estimating the beam displacement at the position with 90 phase advance before the kicker is proposed. The estimated values should be the driving feedback signal. The signals from the different PUs are delayed such that they correspond to the same bunch. Subsequently, a weighted sum of the delayed signals is suggested as an estimator of the feedback correction signal. The

  18. Multiple-electron losses in uranium ion beams in heavy ion synchrotrons

    Science.gov (United States)

    Bozyk, L.; Chill, F.; Litsarev, M. S.; Tolstikhina, I. Yu.; Shevelko, V. P.

    2016-04-01

    Charge changing processes as the result of collisions with residual gas particles are the main cause of beam loss in high energy medium charge state heavy ion beams. To investigate the magnitude of this effect for heavy ion synchrotrons like the planned SIS100 at GSI, the multiple-electron and the total electron-loss cross sections are calculated for Uq+ ions, q = 10, 28, 40, 73, colliding with typical gas components H2, He, C, N2, O2, and Ar at ion energies E = 1 MeV/u-10 GeV/u. The total electron-capture cross sections for U28+ and U73+ ions interacting with these gases are also calculated. Most of these cross sections are new and presented for the first time. Calculated charge-changing cross sections are used to determine the ion-beam lifetimes τ for U28+ ions which agree well with the recently measured values at SIS18/GSI in the energy range E = 10-200 MeV/u. Using simulations made by the StrahlSim code with the reference ion U28+, it is found that in SIS100 the beam loss caused by single and multiple electron losses has only little impact on the residual gas density due to the high efficiency of the ion catcher system.

  19. Molecular beam mass spectrometry with tunable vacuum ultraviolet (VUV) synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Golan, Amir; Ahmed, Musahid

    2012-01-01

    Tunable soft ionization coupled to mass spectroscopy is a powerful method to investigate isolated molecules, complexes and clusters and their spectroscopy and dynamics.[1-4] Fundamental studies of photoionization processes of biomolecules provide information about electronic structure of these systems. Furthermore determinations of ionization energies and other properties of biomolecules in the gas phase are not trivial, and these experiments provide a platform to generate these data. We have developed a thermal vaporization technique coupled with supersonic molecular beams that provides a gentle way to transport these species into the gas phase. Judicious combination of source gas and temperature allows for formation of dimers and higher clusters of the DNA bases. The focus of this particular work is on the effects of non-covalent interactions, i.e., hydrogen bonding, stacking, and electrostatic interactions, on the ionization energies and proton transfer of individual biomolecules, their complexes and upon micro-hydration by water.[1, 5-9] We have performed experimental and theoretical characterization of the photoionization dynamics of gas-phase uracil and 1,3-methyluracil dimers using molecular beams coupled with synchrotron radiation at the Chemical Dynamics Beamline[10] located at the Advanced Light Source and the experimental details are visualized here. This allowed us to observe the proton transfer in 1,3-dimethyluracil dimers, a system with pi stacking geometry and with no hydrogen bonds[1]. Molecular beams provide a very convenient and efficient way to isolate the sample of interest from environmental perturbations which in return allows accurate comparison with electronic structure calculations[11, 12]. By tuning the photon energy from the synchrotron, a photoionization efficiency (PIE) curve can be plotted which informs us about the cationic electronic states. These values can then be compared to theoretical models and calculations and in turn, explain

  20. Molecular beam mass spectrometry with tunable vacuum ultraviolet (VUV) synchrotron radiation.

    Science.gov (United States)

    Golan, Amir; Ahmed, Musahid

    2012-10-30

    Tunable soft ionization coupled to mass spectroscopy is a powerful method to investigate isolated molecules, complexes and clusters and their spectroscopy and dynamics(1-4). Fundamental studies of photoionization processes of biomolecules provide information about the electronic structure of these systems. Furthermore determinations of ionization energies and other properties of biomolecules in the gas phase are not trivial, and these experiments provide a platform to generate these data. We have developed a thermal vaporization technique coupled with supersonic molecular beams that provides a gentle way to transport these species into the gas phase. Judicious combination of source gas and temperature allows for formation of dimers and higher clusters of the DNA bases. The focus of this particular work is on the effects of non-covalent interactions, i.e., hydrogen bonding, stacking, and electrostatic interactions, on the ionization energies and proton transfer of individual biomolecules, their complexes and upon micro-hydration by water(1, 5-9). We have performed experimental and theoretical characterization of the photoionization dynamics of gas-phase uracil and 1,3-dimethyluracil dimers using molecular beams coupled with synchrotron radiation at the Chemical Dynamics Beamline(10) located at the Advanced Light Source and the experimental details are visualized here. This allowed us to observe the proton transfer in 1,3-dimethyluracil dimers, a system with pi stacking geometry and with no hydrogen bonds(1). Molecular beams provide a very convenient and efficient way to isolate the sample of interest from environmental perturbations which in return allows accurate comparison with electronic structure calculations(11, 12). By tuning the photon energy from the synchrotron, a photoionization efficiency (PIE) curve can be plotted which informs us about the cationic electronic states. These values can then be compared to theoretical models and calculations and in turn

  1. Beam Dynamics Studies for High-Intensity Beams in the CERN Proton Synchrotron

    CERN Document Server

    AUTHOR|(CDS)2082016; Benedikt, Michael

    With the discovery of the Higgs boson, the existence of the last missing piece of the Standard Model of particle physics (SM) was confirmed. However, even though very elegant, this theory is unable to explain, for example, the generation of neutrino masses, nor does it account for dark energy or dark matter. To shed light on some of these open questions, research in fundamental particle physics pursues two complimentary approaches. On the one hand, particle colliders working at the high-energy frontier, such as the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN), located in Geneva, Switzerland, are utilized to investigate the fundamental laws of nature. Alternatively, fixed target facilities require high-intensity beams to create a large flux of secondary particles to investigate, for example, rare particle decay processes, or to create neutrino beams. This thesis investigates limitations arising during the acceleration of high-intensity beams at the CERN Proton Synchrotro...

  2. Beam test of a one-dimensional position sensitive chamber on synchrotron radiation

    CERN Document Server

    Mei, Liu; Hui-Rong, Qi; Bao-An, Zhuang; Jian, Zhang; Rong-Guang, Liu; Qi-Ming, Zhu; Qun, Ouyang; Yuan-Bo, Chen; Xiao-Shan, Jiang; Ya-Jie, Wang; Peng, Liu; Guang-Cai, Chang

    2013-01-01

    One-dimensional single-wire chamber was developed to provide high position resolution for powder diffraction experiments with synchrotron radiation. A diffraction test using the sample of SiO2 has been accomplished at 1W2B laboratory of Beijing Synchrotron Radiation Source. The data of beam test were analyzed and some diffraction angles were obtained. The experimental results were in good agreement with standard data from ICDD powder diffraction file. The precision of diffraction angles was 1% to 4.7%. Most of relative errors between measured values of diffraction angles and existing data were less than 1%. As for the detector, the best position resolution in the test was 138 um (sigma value) with an X-ray tube. Finally, discussions of the results were given. The major factor that affected the precision of measurement was deviation from the flat structure of detector. The effect was analyzed and it came to a conclusion that it would be the optimal measurement scheme when the distance between the powder sample...

  3. Electron beam energy stabilization using a neural network hybrid controller at the Australian Synchrotron Linac.

    Energy Technology Data Exchange (ETDEWEB)

    Meier, E.; Morgan, M. J.; Biedron, S. G.; LeBlanc, G.; Wu, J. (OTD-ESE); (Monash Univ.); (Australian Synchrotron Project); (SLAC National Accelerator Lab.)

    2009-01-01

    This paper describes the implementation of a neural network hybrid controller for energy stabilization at the Australian Synchrotron Linac. The structure of the controller consists of a neural network (NNET) feed forward control, augmented by a conventional Proportional-Integral (PI) feedback controller to ensure stability of the system. The system is provided with past states of the machine in order to predict its future state, and therefore apply appropriate feed forward control. The NNET is able to cancel multiple frequency jitter in real-time. When it is not performing optimally due to jitter changes, the system can successfully be augmented by the PI controller to attenuate the remaining perturbations. With a view to control the energy and bunch length at the FERMI{at}Elettra Free Electron Laser (FEL), the present study considers a neural network hybrid feed forward-feedback type of control to rectify limitations related to feedback systems, such as poor response for high jitter frequencies or limited bandwidth, while ensuring robustness of control. The Australian Synchrotron Linac is equipped with a beam position monitor (BPM), that was provided by Sincrotrone Trieste from a former transport line thus allowing energy measurements and energy control experiments. The present study will consequently focus on correcting energy jitter induced by variations in klystron phase and voltage.

  4. Stability of an ion beam in synchrotrons with digital filters in the feedback loop of a transverse damper

    Science.gov (United States)

    Zhabitsky, V. M.

    2010-12-01

    The stability of an ion beam in synchrotrons with digital filters in the feedback loop of a transverse damper is treated. A transverse feedback system (TFS) is required in synchrotrons to stabilize the high intensity ion beams against transverse instabilities and to damp the beam injection errors. The TFS damper kicker (DK) corrects the transverse momentum of a bunch in proportion to its displacement from the closed orbit at the location of the beam position monitor (BPM). The digital signal processing unit in the feedback loop between BPM and DK ensures a condition to achieve optimal damping. Damping rates of the feedback systems with digital filters are analysed in comparison with those in an ideal feedback system.

  5. Simulation study of beam extraction from a synchrotron using colored noise with digital filter

    Science.gov (United States)

    Nakanishi, Tetsuya; Tsuruha, Kohei

    2009-09-01

    A simulation program is developed for a slow-extraction method using a fast Q magnet (FQ) and an RF-knockout. In this extraction method, after the separatrix is produced with excitation of sextupole magnets, a required quantity of circulating beam is extracted by shrinking the separatrix with excitation of the FQ. Then the emittance of circulating beam is diffused to an original size with the RF-knockout. This process is repeated with required timing until the entire circulating beam is completely extracted. An algorithm using a digital filter and white noise is proposed for a colored noise as a signal source for the RF-knockout. Spill structures with the present computing method were similar to the results obtained using a conventional algorithm with the sum of cosines of many frequency components. The results are also in agreement with the experimental results using the HIMAC synchrotron. The computing time of colored noise for simulation of 10 6 turns was 0.5 h for the filter method and 5.0 h for the conventional one. It is indicated that a colored noise with a wider frequency bandwidth gives a better spill structure that smoothly increases with time.

  6. Roundness and straightness measurement of ceramic beam ducts for the 3 GeV-synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Nishizawa, Daiji; Kinsho, Michikazu; Kanazawa, Kenichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kubo, Tomio; Sato, Yoshihiro; Saito, Yoshio [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

    2001-12-01

    Large aperture ({phi}200 - {phi}250) cylindrical beam ducts consisting of alumina ceramics will be used in the 3 GeV-synchrotron of High Intensity Proton Accelerator Facility. In particular, bending magnet sections require the large length ({approx}3500 mm) ceramic beam duct connecting several unit ducts whose length is around 500-1000 mm by metallizing and glazing. Therefore it is very important to evaluate roundness and straightness of ceramic ducts because we have to compensate contact area large and have to minimize misalignment of ducts connected. We developed an apparatus for measuring roundness and straightness, and we completed data analysis method using general application software Excel as well as measuring method. Then we have taken data, and have evaluated value of roundness and straightness for the first time about 7 pieces (3 kinds) of ceramic beam duct. At last we have found out that unit ceramic ducts can be made after sintering without polishing with roundness several hundred micron ({mu}m) and straightness around 0.2-1 mm, and that straightness has a tendency to become large as duct length increases as well as roundness increases directly proportional to the maximum oblateness. (author)

  7. Synchrotron beam test of a photon counting pixel prototype based on Double-SOI technology

    Science.gov (United States)

    Zhou, Y.; Lu, Y.; Hashimoto, R.; Nishimura, R.; Kishimoto, S.; Arai, Y.; Ouyang, Q.

    2017-01-01

    The overall noise performances and first synchrotron beam measurement results of CPIXETEG3b, the first counting type Silicon-On-Insulator (SOI) pixel sensor prototype without crosstalk issue, are reported. The prototype includes a 64 × 64 pixel matrix with 50 μm pitch size. Each pixel consists of an N-in-P charge collection diode, a charge sensitive preamplifier, a shaper, a discriminator with thresholds adjustable by an in-pixel 4-bit DAC, and a 6-bit counter. The study was performed using the beam line 14A at KEK Photon Factory (KEK-PF) . The homogeneous response of the prototype, including charging-sharing effects between pixels were studied. 16 keV and 8 keV monochromatic small size (~ 10 μm diameter) X-ray beams were used for the charge sharing study, and a flat-field was added for homogenous response investigation. The overall detector homogeneity and the influence of basic detector parameters on charge sharing between pixels has been investigated.

  8. Beam-machine interaction at TLEP : first evaluation and mitigation of the synchrotron radiation impact

    CERN Document Server

    Lari, L; Ferrari, A; Mereghetti, A

    2014-01-01

    In the framework of post-LHC accelerator studies, TLEP is a proposed high-luminosity circular e+e- collider, aimed at measuring the properties of the Higgs boson H(126) with unprecedented accuracy, as well as those of the W boson, the Z boson and the top quark. In order to calculate the impact of synchrotron radiation, the latter has been implemented in the FLUKA code as new source term. A first account of escaping power as a function of the vacuum chamber shielding thickness, photoneutron production, and activation has been obtained for the 80 km circumference 175 GeV (beam energy) TLEP option. Starting from a preliminary layout of the FODO cell and a possible dipole design, energy deposition simulations have been carried out, investigating the effectiveness of absorbers in the interconnections. The results provide inputs to improve the cell design and to support mechanical integration studies

  9. Investigation of GEM-Micromegas Detector on X-ray Beam of Synchrotron Radiation

    CERN Document Server

    Zhang, YuLian; Hu, BiTao; Fan, ShengNan; Wang, Bo; Liu, Mei; Zhang, Jian; Liu, RongGuang; Chang, GuangCai; Liu, Peng; Ouyang, Qun; Chen, YuanBo; Yi, FuTing

    2013-01-01

    To solve the discharge of the standard Bulk Micromegas and GEM detector, the GEM-Micromegas detector was developed in Institute of High Energy Physics. Taking into account the advantages of the two detectors, one GEM foil was set as a preamplifier on the mesh of Micromegas in the structure and the GEM preamplification decreased the working voltage of Micromegas to reduce the effect of the discharge significantly. In the paper, the performance of detector in X-ray beam was studied at 1W2B laboratory of Beijing Synchrotron Radiation Facility. Finally, the result of the energy resolution under various X-ray energies was given in different working gases. It indicated that the GEM-Micromegas detector had the energy response capability in all the energy range and it could work better than the standard Bulk-Micromegas.

  10. Single-particle And Collective Effects Of Cubic Nonlinearity In The Beam Dynamics Of Proton Synchrotrons

    CERN Document Server

    Tran Hy, J

    1998-01-01

    This thesis describes some new studies of the effects of cubic nonlinearities arising from image-charge forces and octupole magnets on the transverse beam dynamics of proton synchrotrons and storage rings, and also a study of the damping of coherent oscillations using a feed-back damper. In the latter case, various corrective algorithms were modeled using linear one-turn maps. Kicks of fixed amplitude but appropriate sign were shown to provide linear damping and no coherent tune shift, though the rate predicted analytically was somewhat higher than that observed in simulations. This algorithm gave much faster damping (for equal power) than conventional proportional kicks, which damp exponentially. Two single-particle effects of the image-change force were investigated: distortion of the momentum dispersion function and amplitude dependence of the betatron tunes (resulting in tune spread). The former is calculated using transfer maps and the method of undetermined coefficients, the latter by solving the cubic ...

  11. Study of charge-sharing in MEDIPIX3 using a micro-focused synchrotron beam

    Science.gov (United States)

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

    2011-01-01

    X-ray photon-counting detectors consisting of a silicon pixel array sensor bump-bonded to a CMOS electronic readout chip offer several advantages over traditional X-ray detection technologies used for synchrotron applications. They offer high frame rate, dynamic range, count rate capability and signal-to-noise ratio. A survey of the requirements for future synchrotron detectors carried out at the Diamond Light Source synchrotron highlighted the needs for detectors with a pixel size of the order of 50μm. Reducing the pixel size leads to an increase of charge-sharing events between adjacent pixels and, therefore, to a degradation of the energy resolution and image quality of the detector. This effect was observed with MEDIPIX2, a photon-counting readout chip with a pixel size of 55μm. The lastest generation of the MEDIPIX family, MEDIPIX3, is designed to overcome this charge-sharing effect in an implemented readout operating mode referred to as Charge Summing Mode. MEDIPIX3 has the same pixel size as MEDIPIX2, but it is implemented in an 8-metal 0.13μm CMOS technology which enables increased functionality per pixel. The present work focuses on the study of the charge-sharing effect when the MEDIPIX3 is operated in Charge Summing Mode compared to the conventional readout mode, referred to as Single Pixel Mode. Tests of a standard silicon photodiode array bump-bonded to MEDIPIX3 were performed in beamline B16 at the Diamond Light Source synchrotron. A monochromatic micro-focused beam of 2.9μm x 2.2μm size at 15keV was used to scan a cluster of nine pixels in order to study the charge collection and X-ray count allocation process for each readout mode, Single Pixel Mode and Charge Summing Mode. The study showed that charge-shared events were eliminated when Medipix3 was operated in Charge Summing Mode.

  12. Special diagnostic methods and beam loss control on high intensity proton synchrotrons and storage rings Circular proton accelerator

    CERN Document Server

    Warsop, C M

    2002-01-01

    Two topics concerning high intensity, medium energy, circular proton accelerators have been studied: specialist diagnostics and beam loss control. The use of specially configured, low intensity diagnostic beams to help measure, understand and control high intensity beams is described. The ideas are developed and demonstrated on the ISIS 800 MeV, high intensity proton synchrotron at the Rutherford Appleton Laboratory in the UK. It is shown that these techniques make much new and valuable information available, which is particularly useful in achieving the precise beam optimisation required for low and controlled losses. Beam loss control in the proposed European Spallation Source (ESS) accumulator rings is studied. The expected losses are summarised, and a design for the beam collimation system presented. A new code for the simulation of loss control is outlined, and then used to test the collimation system under most foreseeable conditions. It is expected that the required loss control levels will be achievab...

  13. Energy dependent charge spread function in a dedicated synchrotron beam pnCCD detector

    Energy Technology Data Exchange (ETDEWEB)

    Yousef, Hazem

    2011-05-20

    A scan on the pixel edges is the method which is used to resolve the electron cloud size in the pixel array of the pnCCD detector. The EDR synchrotron radiation in BESSY is the source of the X-ray photons which are used in the scans. The radius of the electron cloud as a function of the impinging photon energy is analyzed. The angle of incidence of the X-ray beam is employed in the measurements. The measurements are validated by the numerical simulation models. The inclined X-ray track leads to distribute the electron clouds in a certain number of pixels according to the incident angle of the X-ray beam. The pixels detect different electron clouds according to their generation position in the detector bulk. A collimated X-ray beam of 12.14 keV is used in the measurements with 30 and 40 entrance angles. It is shown that the two factors that leads to expand the electron clouds namely the diffusion and the mutual electrostatic repulsion can be separated from the measured electron clouds. It is noticed as well that the influence of the mutual electrostatic repulsion dominates the cloud expansion over the diffusion process in the collection time of the detector. The perpendicular X-ray track leads to determine the average radius of the electron cloud per photon energy. The results show that the size of the electron clouds (RMS) in the energy range of [5.0-21.6] keV is smaller than the pixel size. (orig.)

  14. X-ray diffraction using synchrotron radiation on the G.I.L.D.A. beam line at the E.S.R.F

    Energy Technology Data Exchange (ETDEWEB)

    Balerna, A. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Meneghini, C. [INFN, Laboratori Nazionali di Frascati, Rome (Italy)]|[INFM, Genoa (Italy); Bordoni, S. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica; Mobilio, S. [Rome Univ. III (Italy). Dip. di Fisica `E. Amaldi`

    1996-09-01

    The aim of this lecture is to make a short introduction on Synchrotron radiation, its history and main properties. The main components of a synchrotron radiation beam line will be described. The Italian beam line, General purpose Italian beam line Line for Diffraction and Absorption (G.I.L.D.A.) at the European Synchrotron Radiation Facility (E.S.R.F.) in Grenoble will be used as an example. The G.I.L.D.A. diffractometer will be described in detail reporting also some experimental results.

  15. Thermal analysis of injection beam dump of high-intensity rapid-cycling synchrotron in J-PARC

    Science.gov (United States)

    Kamiya, J.; Saha, P. K.; Yamamoto, K.; Kinsho, M.; Nihei, T.

    2017-10-01

    The beam dump at the beam injection area in the J-PARC 3-GeV rapid cycling synchrotron (RCS) accepts beams that pass through the charge exchange foil without ideal electron stripping during the multi-turn beam injection. The injection beam dump consists of the beam pipe, beam stopper, radiation shield, and cooling mechanism. The ideal beam power into the injection beam dump is 400 W in the case of design RCS extraction beam power of 1 MW with a healthy foil, which has 99.7 % charge stripping efficiency. On the other hand, as a radiation generator, the RCS is permitted to be operated with maximum average beam power of 4 kW into the injection beam dump based on the radiation shielding calculation, in consideration of lower charge stripping efficiency due to the foil deterioration. In this research, to evaluate the health of the RCS injection beam dump system from the perspective of the heat generation, a thermal analysis was performed based on the actual configuration with sufficiently large region, including the surrounding concrete and soil. The calculated temperature and heat flux density distribution showed the validity of the mesh spacing and model range. The calculation result showed that the dumped 4 kW beam causes the temperature to increase up to 330, 400, and 140 °C at the beam pipe, beam stopper, and radiation shield, respectively. Although these high temperatures induce stress in the constituent materials, the calculated stress values were lower than the ultimate tensile strength of each material. Transient temperature analysis of the beam stopper, which simulated the sudden break of the charge stripper foil, demonstrated that one bunched beam pulse with the maximum beam power does not lead to a serious rise in the temperature of the beam stopper. Furthermore, from the measured outgassing rate of stainless steel at high temperature, the rise in beam line pressure due to additive outgassing from the heated beam pipe was estimated to have a negligible

  16. Transverse beam splitting made operational: Recent progress of the multi-turn extraction at the CERN proton synchrotron

    CERN Document Server

    AUTHOR|(CDS)2082016; Borburgh, Jan; Damjanovic, Sanja; Gilardoni, Simone; Giovannozzi, Massimo; Hourican, Michael; Kahle, Karsten; Michels, Olivier; Sterbini, Guido; Hernalsteens, Cedric; Le Godec, Gilles

    2016-01-01

    Following a successful commissioning period, the Multi-Turn Extraction (MTE) at the CERN Proton Synchrotron (PS) has been applied for the fixed-target physics programme at the Super Proton Synchrotron (SPS) since September 2015. This exceptional extraction technique was proposed to replace the long-serving Continuous Transfer (CT) extraction, which has the drawback of inducing high activation in the ring. MTE exploits the principles of non-linear beam dynamics to perform loss-free beam splitting in the horizontal phase space. Over multiple turns, the resulting beamlets are then transferred to the downstream accelerator. The operational deployment of MTE was rendered possible by the full understanding and mitigation of different hardware limitations and by redesigning the extraction trajectories and non-linear optics, which was required due to the installation of a dummy septum to reduce the activation of the magnetic extraction septum. The results of the related experimental and simulation studies, a summary ...

  17. Development of the microstrip silicon detector for imaging of fast processes at a synchrotron radiation beam

    Science.gov (United States)

    Aulchenko, V.; Pruuel, E.; Shekhtman, L.; Ten, K.; Tolochko, B.; Zhulanov, V.

    2017-02-01

    In situ imaging of explosions allows to study material properties under very high pressures and temperatures. Synchrotron radiation (SR) is a powerful tool for such studies because of its unique time structure. Flashes of X-rays from individual bunches in a storage ring are so short that an object under study does not move more than 1-10 μm during exposure. If a detector is able to store images synchronously with bunches of an SR source the time resolution of such method will be determined by the duration of SR flash from individual bunch. New beam line at the VEPP-4M storage ring will allow to get X-Ray flux from each bunch close to 106 photons/channel where channel area is 0.05×0.5 mm2 and average beam energy is about 30 keV. Bunches in the machine can be grouped into trains with 20 ns time gap. In order to meet these requirements a new detector development was started based on Si microstrip technology. The detector with a new dedicated front-end chip will be able to record images with maximum signal equivalent to 106 photons/channel, with signal to noise ratio of ∼103, spatial resolution of 50 μm and maximum frame rate of 50 MHz. The detector has to drive very high peak and average currents without affecting the front-end chip, therefore a specific design of Si sensor should be developed. The front-end chip has to provide signal measurements with the dynamic range of about 104 or more and recording of the signal to an analogue memory with the rate of 50 MHz. The concept of such detector is discussed in the paper. The results of the simulations of the main detector parameters and the results of the first measurements with the prototype sensors are presented.

  18. Investigation of GEM-Micromegas detector on X-ray beam of synchrotron radiation

    Science.gov (United States)

    Zhang, Yu-Lian; Qi, Hui-Rong; Hu, Bi-Tao; Fan, Sheng-Nan; Wang, Bo; Liu, Mei; Zhang, Jian; Liu, Rong-Guang; Chang, Guang-Cai; Liu, Peng; Ouyang, Qun; Chen, Yuan-Bo; Yi, Fu-Ting

    2014-04-01

    To reduce the discharge of the standard bulk Micromegas and GEM detectors, a GEM-Micromegas detector was developed at the Institute of High Energy Physics. Taking into account the advantages of the two detectors, one GEM foil was set as a preamplifier on the mesh of Micromegas in the structure and the GEM preamplification decreased the working voltage of Micromegas to significantly reduce the effect of the discharge. At the same gain, the spark probability of the GEM-Micromegas detector can be reduced to a factor 0.01 compared to the standard Micromegas detector, and an even higher gain could be obtained. This paper describes the performance of the X-ray beam detector that was studied at 1W2B Laboratory of Beijing Synchrotron Radiation Facility. Finally, the result of the energy resolution under various X-ray energies was given in different working gases. This indicates that the GEM-Micromegas detector has an energy response capability in an energy range from 6 keV to 20 keV and it could work better than the standard bulk-Micromegas.

  19. Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam

    CERN Document Server

    Watt, J; Campbell, M; Mathieson, K; Mikulec, B; O'Shea, V; Passmore, M S; Schwarz, C; Smith, K M; Whitehill, C

    2001-01-01

    Hybrid semiconductor pixel detectors are being investigated as imaging devices for radiography and synchrotron radiation beam applications. Based on previous work in the CERN RD19 and the UK IMPACT collaborations, a photon counting GaAs pixel detector (PCD) has been used in an X-ray powder diffraction experiment. The device consists of a 200 mu m thick SI-LEC GaAs detector patterned in a 64*64 array of 170 mu m pitch square pixels, bump-bonded to readout electronics operating in single photon counting mode. Intensity peaks in the powder diffraction pattern of KNbO/sub 3/ have been resolved and compared with results using the standard scintillator, and a PCD predecessor (the Omega 3). The PCD shows improved speed, dynamic range, 2-D information and comparable spatial resolution to the standard scintillator based systems. It also overcomes the severe dead time limitations of the Omega 3 by using a shutter based acquisition mode. A brief demonstration of the possibilities of the system for dental radiography and...

  20. Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam

    Energy Technology Data Exchange (ETDEWEB)

    Watt, J. E-mail: j.watt@physics.gla.ac.uk; Bates, R.; Campbell, M.; Mathieson, K.; Mikulec, B.; O' Shea, V.; Passmore, M-S.; Schwarz, C.; Smith, K.M.; Whitehill, C

    2001-03-11

    Hybrid semiconductor pixel detectors are being investigated as imaging devices for radiography and synchrotron radiation beam applications. Based on previous work in the CERN RD19 and the UK IMPACT collaborations, a photon counting GaAs pixel detector (PCD) has been used in an X-ray powder diffraction experiment. The device consists of a 200 {mu}m thick SI-LEC GaAs detector patterned in a 64x64 array of 170 {mu}m pitch square pixels, bump-bonded to readout electronics operating in single photon counting mode. Intensity peaks in the powder diffraction pattern of KNbO{sub 3} have been resolved and compared with results using the standard scintillator, and a PCD predecessor (the {omega}3). The PCD shows improved speed, dynamic range, 2-D information and comparable spatial resolution to the standard scintillator based systems. It also overcomes the severe dead time limitations of the {omega}3 by using a shutter based acquisition mode. A brief demonstration of the possibilities of the system for dental radiography and image processing are given, showing a marked reduction in patient dose and dead time compared with film.

  1. A first-order matrix approach to the analysis of electron beam emittance growth caused by coherent synchrotron radiation

    CERN Document Server

    Hajima, R

    2003-01-01

    A first-order transform matrix is proposed for calculating electron beam emittance dilution arising from coherent synchrotron radiation (CSR) in a next-generation light source based on an energy-recovery linac. The matrix approach enables us to scan numerous parameters for the design of achromatic cells of minimum emittance dilution. The emittance dilution can be minimized when the envelope of CSR wake dispersion matches the betatron function envelope at the achromatic cell exit. (author)

  2. Beam Stability in Synchrotrons with Notch and All-Pass Filters in the Feedback Loop of a Transverse Damper

    CERN Document Server

    Zhabitsky, V M; Kotzian, G

    2009-01-01

    The stability of a beam in synchrotrons with digital filters in the feedback loop of a transverse damper is treated. A transverse feedback system (TFS) is required in synchrotrons to stabilize the high intensity beams against transverse instabilities and to damp the beam injection errors. The TFS damper kicker (DK) corrects the transverse momentum of a bunch in proportion to its displacement from the closed orbit at the location of the beam position monitor (BPM). The digital signal processor in the feedback loop between BPM and DK ensures the adjustment of the phase advance and the correction of the time of flight for optimum damping. Digital FIR (finite impulse response) and IIR (infinite impulse response) filters are used commonly for the signal processing. A notch filter with zeros at the revolution frequency is required to remove the closed orbit content of the signal and correct for the imperfect electric centre of the BPM. Further processing is required to adjust for the betatron phase advance between ...

  3. Characteristics of extracted beam from a synchrotron using a fast Q-magnet assisted by RF-knockout

    Science.gov (United States)

    Nakanishi, Tetsuya; Furukawa, Takuji; Noda, Koji

    2008-05-01

    Beam experiment has been carried out at the HIMAC synchrotron to study characteristics of a beam extracted with alternate operation of a fast Q-magnet (FQ) to extract and RF-knockout to diffuse a circulating beam. The FQ coil current of a chopping wave was used to find a particle density distribution after the diffusion. Two kinds of RF-knockout signal were used: a colored noise and a frequency modulation signal. The results showed that the spill structure was like an exponential wave pattern roughly and nearly constant by use of the colored noise and was varied with the frequency modulation signal. The colored noise also gave a nearly constant diffusion rate.

  4. Measurement and simulation of the impact of coherent synchrotron radiation on the Jefferson Laboratory energy recovery linac electron beam

    Science.gov (United States)

    Hall, C. C.; Biedron, S. G.; Edelen, A. L.; Milton, S. V.; Benson, S.; Douglas, D.; Li, R.; Tennant, C. D.; Carlsten, B. E.

    2015-03-01

    In an experiment conducted on the Jefferson Laboratory IR free-electron laser driver, the effects of coherent synchrotron radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR recirculator. Here we examine the impact of CSR on the average energy loss as a function of bunch compression as well as the impact of CSR on the energy spectrum of the bunch. Simulation of beam dynamics in the machine, including the one-dimensional CSR model, shows very good agreement with the measured effect of CSR on the average energy loss as a function of compression. Finally, a well-defined structure is observed in the energy spectrum with a feature in the spectrum that varies as a function of the compression. This effect is examined in simulations, as well, and a simple explanation for the variation is proposed.

  5. Identification of Intermediates in Pyridine Pyrolysis with Molecular-beam Mass Spectrometry and Tunable Synchrotron VUV Photoionization

    Institute of Scientific and Technical Information of China (English)

    Xin Hong; Taichang Zhang; Lidong Zhang; Fei Qi

    2009-01-01

    The pyrolysis of pyridine (5.26% pyridine in argon) was performed with tunable synchrotron vacuum ultraviolet photoionization and molecular-beam mass spectrometry technique at the temperature range of 1255-1765 K at 267 Pa. About 20 products and intermediates, containing major species H2, HCN, C2H2, C5H3N, C4H2, and C3H3N, were identified by near-threshold measurements of photoionization mass spectra and their mole fractions vs.temperatures were estimated. The major reaction pathways are analyzed based on the experimental observations.

  6. Design and fabrication of soft x-ray photolithography experimental beam line at Beijing National Synchrotron Radiation Laboratory

    Science.gov (United States)

    Zhou, Changxin

    1991-08-01

    The synchrotron radiation (SR) soft x-ray photolithography experimental beam line (3B1 beam line) at Beijing National Synchrotron Radiation Laboratory, was completed and tested in June 1990. A soft x-ray photolithography experiment was successfully completed, and the width of linear etch on a silicon chip by the device with a 3B1 beam line is up to 0.5 micrometers . This SR soft x-ray photolithography experiment was done successfully for the first time in China. This paper describes the design of the beam line and the fabrication of the most important optical element--the cylindrical scanning mirror in the beam line. The 3B1 beam line consists of the shielding light plate with water-cooling, laser simulation light source system, 3-D adjustable scanning mirror, high pass-band filer (beryllium window), acoustic sensor, helium gas chamber, and vacuum system. The main specifications of the 3B1 beam line are as follows: spectral range 0.4-2 nm; horizontal acceptance angle 7.5 mrad; vertical acceptance angle 0.4 mrad; grazing incidence angle 1.5 deg; light spot size 35 nm X 12 nm; vacuum degree of the mirror box 5 X 10-10 torr (static). The cylindrical scanning mirror in grazing incidence is used in the beam line for photolithography to obtain uniform distributed intensity of illumination of the SR source in the vertical direction (Gaussian distribution) and sufficiently concentrated energy. It is made of aluminum alloy LD2 with a supersmooth optical surface. The curvature radius of the cylindrical surface is 527.5 mm; surface figure error is less than (lambda) /10; surface roughness is better than 1 nm RMS, and fold coating on the surface of the mirror under UHV of 109 torr. The laser simulation light source system is used for adjusting the optical system in the beam line instead of the SR source. The cylindrical mirror was polished supersmoothly using Al2O3 ultra micropower grinding material made in TOMAS in Japan on modified traditional machine tools, and surface

  7. Applications of Synchrotron Radiation Micro Beams in Cell Micro Biology and Medicine

    CERN Document Server

    Ide-Ektessabi, Ari

    2007-01-01

    This book demonstrates the applications of synchrotron radiation in certain aspects of cell microbiology, specifically non-destructive elemental analyses, chemical-state analyses and imaging (distribution) of the elements within a cell. The basics for understanding and applications of synchrotron radiation are also described to make the contents easier to be understood for a wide group of researchers in medical and biological sciences who might not be familiar with the physics of synchrotron radiation. The two main techniques that are discussed in this book are the x-ray fluorescence spectroscopy (XRF) and the x-ray fine structure analysis (XAFS). Application of these techniques in investigations of several important scientific fields, such as neurodegeneration and other diseases related to cell malfunctioning, are demonstrated in this book.

  8. Parallel Modem Architectures for High-Data-Rate Space Modems

    Science.gov (United States)

    Satorius, E.

    2014-08-01

    Existing software-defined radios (SDRs) for space are limited in data volume by several factors, including bandwidth, space-qualified analog-to-digital converter (ADC) technology, and processor throughput, e.g., the throughput of a space-qualified field-programmable gate array (FPGA). In an attempt to further improve the throughput of space-based SDRs and to fully exploit the newer and more capable space-qualified technology (ADCs, FPGAs), we are evaluating parallel transmitter/receiver architectures for space SDRs. These architectures would improve data volume for both deep-space and particularly proximity (e.g., relay) links. In this article, designs for FPGA implementation of a high-rate parallel modem are presented as well as both fixed- and floating-point simulated performance results based on a functional design that is suitable for FPGA implementation.

  9. Molecular beam studies of unimolecular and bimolecular chemical reaction dynamics using VUV synchrotron radiation as a product probe

    Energy Technology Data Exchange (ETDEWEB)

    Blank, David Andrew [Univ. of California, Berkeley, CA (United States)

    1997-08-01

    This dissertation describes the use of a new molecular beam apparatus designed to use tunable VUV synchrotron radiation for photoionization of the products from scattering experiments. The apparatus was built at the recently constructed Advanced Light Source at Lawrence Berkeley National Laboratory, a third generation 1-2 GeV synchrotron radiation source. The new apparatus is applied to investigations of the dynamics of unimolecular reactions, photodissociation experiments, and bimolecular reactions, crossed molecular beam experiments. The first chapter describes the new apparatus and the VUV radiation used for photoionization. This is followed by a number of examples of the many advantages provided by using VUV photoionization in comparison with the traditional technique of electron bombardment ionization. At the end of the chapter there is a discussion of the data analysis employed in these scattering experiments. The remaining four chapters are complete investigations of the dynamics of four chemical systems using the new apparatus and provide numerous additional examples of the advantages provided by VUV photoionizaiton of the products. Chapters 2-4 are photofragment translational spectroscopy studies of the photodissociation dynamics of dimethyl sulfoxide, acrylonitrile, and vinyl chloride following absorption at 193 mn. All of these systems have multiple dissociation channels and provide good examples of the ability of the new apparatus to unravel the complex UV photodissociation dynamics that can arise in small polyatomic molecules.

  10. Beam Measurements of the Longitudinal impedance of the CERN Super Proton Synchrotron

    CERN Document Server

    AUTHOR|(CDS)2090034; Petrache, Costel

    One of the main challenges of future physics projects based on particle accelerators is the need for high intensity beams. However, collective effects are a major limitation which can deteriorate the beam quality or limit the maximum intensity due to losses. The CERN SPS, which is the last injector for the LHC, is currently unable to deliver the beams required for future projects due to longitudinal instabilities. The numerous devices in the machine (accelerating RF cavities, injection and extraction magnets, vacuum flanges. etc.) lead to variations in the geometry and material of the chamber through which the beam is travelling. The electromagnetic interaction within the beam (space charge) and of the beam with its environment are described by a coupling impedance which affects the motion of the particles and leads to instabilities for high beam intensities. Consequently, the critical impedance sources should be identified and solutions assessed. To have a reliable impedance model of an accelerator, the...

  11. Study of thin oxide films by electron, ion and synchrotron radiation beams

    CERN Document Server

    Sammelselg, V; Tarre, A; Asari, J; Rauhala, E; Arstila, K; Seppaelae, A; Zakharov, A; Aarik, J; Karlis, J; Martinson, Indrek

    2002-01-01

    Titanium oxide and zirconium oxide thin films deposited on silicon substrates were characterized using electron probe microanalysis (EPMA), Rutherford backscattering spectroscopy (RBS), time-of-flight elastic recoil detection analysis (TOF-ERDA) and scanning photoelectron microscopy (SPEM). The composition and mass thickness of the films were determined and the results of different methods compared. lt was revealed that the synchrotron radiation used for SPEM studies caused considerable modification of zirconia films grown at low temperatures. (author)

  12. Study of charge-sharing in MEDIPIX3 using a micro-focused synchrotron beam

    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

    X-ray photon-counting detectors consisting of a silicon pixel array sensor bump-bonded to a CMOS electronic readout chip offer several advantages over traditional X-ray detection technologies used for synchrotron applications. They offer high frame rate, dynamic range, count rate capability and signal-to-noise ratio. A survey of the requirements for future synchrotron detectors carried out at the Diamond Light Source synchrotron highlighted the needs for detectors with a pixel size of the order of 50 mu m. Reducing the pixel size leads to an increase of charge-sharing events between adjacent pixels and, therefore, to a degradation of the energy resolution and image quality of the detector. This effect was observed with MEDIPIX2, a photon-counting readout chip with a pixel size of 55 mu m. The lastest generation of the MEDIPIX family, MEDIPIX3, is designed to overcome this charge-sharing effect in an implemented readout operating mode referred to as Charge Summing Mode. MEDIPIX3 has the same pixel size as MEDI...

  13. BNL alternating gradient synchrotron with four helical magnets to minimize the losses of the polarized proton beam

    Science.gov (United States)

    Tsoupas, N.; Huang, H.; MacKay, W. W.; Meot, F.; Roser, T.; Trbojevic, D.

    2013-04-01

    The principle of using multiple partial helical magnets to preserve the polarization of the proton beam during its acceleration was applied successfully to the alternating gradient synchrotron (AGS) which currently operates with two partial helical magnets. In this paper we further explore this idea by using four partial helical magnets placed symmetrically in the AGS ring. This provides many advantages over the present setup of the AGS, which uses two partial helical magnets. First, the symmetric placement of the four helical magnets and their relatively lower field of operation allows for better control of the AGS optics with reduced values of the beta functions especially near beam injection and allows both the vertical and horizontal tunes to be placed within the “spin tune gap,” therefore eliminating the horizontal and vertical intrinsic spin resonances of the AGS during the acceleration cycle. Second, it provides a wider spin tune gap. Third, the vertical spin direction during beam injection and extraction is closer to vertical. Although the spin tune gap, which is created with four partial helices, can also be created with a single or two partial helices, the high field strength of a single helical magnet which is required to generate such a spin tune gap makes the use of the single helical magnet impractical, and that of the two helical magnets rather difficult. In this paper we will provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and compare them with those from the present setup of the AGS that uses two partial helical magnets. Although in this paper we specifically discuss the effect of the four partial helices on the AGS, this method which can eliminate simultaneously the vertical and horizontal intrinsic spin resonances is a general method and can be applied to any medium energy synchrotron which operates in similar energy range like the AGS and provides the required space to accommodate the four

  14. BNL alternating gradient synchrotron with four helical magnets to minimize the losses of the polarized proton beam

    Directory of Open Access Journals (Sweden)

    N. Tsoupas

    2013-04-01

    Full Text Available The principle of using multiple partial helical magnets to preserve the polarization of the proton beam during its acceleration was applied successfully to the alternating gradient synchrotron (AGS which currently operates with two partial helical magnets. In this paper we further explore this idea by using four partial helical magnets placed symmetrically in the AGS ring. This provides many advantages over the present setup of the AGS, which uses two partial helical magnets. First, the symmetric placement of the four helical magnets and their relatively lower field of operation allows for better control of the AGS optics with reduced values of the beta functions especially near beam injection and allows both the vertical and horizontal tunes to be placed within the “spin tune gap,” therefore eliminating the horizontal and vertical intrinsic spin resonances of the AGS during the acceleration cycle. Second, it provides a wider spin tune gap. Third, the vertical spin direction during beam injection and extraction is closer to vertical. Although the spin tune gap, which is created with four partial helices, can also be created with a single or two partial helices, the high field strength of a single helical magnet which is required to generate such a spin tune gap makes the use of the single helical magnet impractical, and that of the two helical magnets rather difficult. In this paper we will provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and compare them with those from the present setup of the AGS that uses two partial helical magnets. Although in this paper we specifically discuss the effect of the four partial helices on the AGS, this method which can eliminate simultaneously the vertical and horizontal intrinsic spin resonances is a general method and can be applied to any medium energy synchrotron which operates in similar energy range like the AGS and provides the required space to

  15. Beam heat load investigations with a cold vacuum chamber for diagnostics in a synchrotron light source

    Energy Technology Data Exchange (ETDEWEB)

    Voutta, Robert

    2016-04-22

    The beam heat load is a crucial input parameter for the cryogenic design of superconducting insertion devices. To understand the discrepancies between the predicted heat load of an electron beam to a cold bore and the heat load observed in superconducting devices, a cold vacuum chamber for diagnostics has been built. Extensive beam heat load measurements were performed at the Diamond light source. They are analysed systematically and combined with complementary impedance bench measurements.

  16. Beam heat load investigations with a cold vacuum chamber for diagnostics in a synchrotron light source

    OpenAIRE

    Voutta, Robert

    2016-01-01

    The beam heat load is a crucial input parameter for the cryogenic design of superconducting insertion devices. To understand the discrepancies between the predicted heat load of an electron beam to a cold bore and the heat load observed in superconducting devices, a cold vacuum chamber for diagnostics has been built. Extensive beam heat load measurements were performed at the Diamond light source. They are analysed systematically and combined with complementary impedance bench measurements.

  17. Design, fabrication and testing of elliptical crystal bender for the EXAFS beam-line at INDUS-II synchrotron source

    Indian Academy of Sciences (India)

    N C Das; S N Jha; D Bhattacharyya; A K Poswal; A K Sinha; V K Mishra

    2004-10-01

    An extended X-ray absorption fine structure (EXAFS) beam-line for X-ray absorption studies using energy dispersive geometry and position sensitive detector is being developed for the INDUS-II synchrotron source. The optical design of the beam-line has been completed based on the working principle that a single crystal bent in the shape of an ellipse by a crystal bender would act as a dispersing as well as focusing element. The heart of the beam-line is the crystal bender which has been designed on the basis of the principle of four-point bending and has been fabricated indigenously. The crystal bender is capable of producing pre-defined elliptical curvature on a crystal surface by applying different couples at the two-ends of the crystal which has variable width along its length. The focusing property of the crystal bender has been tested using a laser source and has been compared with the theoretically simulated results.

  18. Panofsky magnet for the beam extraction from the synchrotron using a fast Q-magnet and RF-knockout

    Science.gov (United States)

    Masubuchi, S.; Nakanishi, T.

    2011-12-01

    The fast control of the beam spill extracted from a synchrotron is a key function for the spot scanning irradiation in cancer therapy application. The authors propose an extraction method which uses the quadruple field of fast response, as well as the RF-knockout. A Panofsky magnet was developed as a quadruple magnet, with a frequency response of around 10 kHz. The Panofsky magnet has a rectangular beam aperture and plate coils attached to the pole face. A model magnet has been manufactured with ferrite, and static and dynamic magnetic fields were measured. From the measurement we observed that the effects of eddy current in the plate coils were large and the uniformity of the magnetic field gradient in the beam aperture was worse than ±5% with a plate thickness of 0.02 cm and a frequency of current of 10 kHz. For the future, in a detailed design the eddy current effects have to be taken into account.

  19. Panofsky magnet for the beam extraction from the synchrotron using a fast Q-magnet and RF-knockout

    Energy Technology Data Exchange (ETDEWEB)

    Masubuchi, S., E-mail: cisa09016@g.nihon-u.ac.jp [College of Industrial Technology, Nihon University, 1-2-1 Izumicho, Narashino, Chiba 275-8575 (Japan); Nakanishi, T., E-mail: nakanishi.tetsuya@nihon-u.ac.jp [College of Industrial Technology, Nihon University, 1-2-1 Izumicho, Narashino, Chiba 275-8575 (Japan)

    2011-12-15

    The fast control of the beam spill extracted from a synchrotron is a key function for the spot scanning irradiation in cancer therapy application. The authors propose an extraction method which uses the quadruple field of fast response, as well as the RF-knockout. A Panofsky magnet was developed as a quadruple magnet, with a frequency response of around 10 kHz. The Panofsky magnet has a rectangular beam aperture and plate coils attached to the pole face. A model magnet has been manufactured with ferrite, and static and dynamic magnetic fields were measured. From the measurement we observed that the effects of eddy current in the plate coils were large and the uniformity of the magnetic field gradient in the beam aperture was worse than {+-}5% with a plate thickness of 0.02 cm and a frequency of current of 10 kHz. For the future, in a detailed design the eddy current effects have to be taken into account.

  20. Measurements and modeling of coherent synchrotron radiation and its impact on the Linac Coherent Light Source electron beam

    Science.gov (United States)

    Bane, K. L. F.; Decker, F.-J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J.; Huang, Z.; Iverson, R.; Limborg-Deprey, C.; Loos, H.; Nuhn, H.-D.; Ratner, D.; Stupakov, G.; Turner, J.; Welch, J.; Wu, J.

    2009-03-01

    In order to reach the high peak current required for an x-ray free electron laser, two separate magnetic dipole chicanes are used in the Linac Coherent Light Source accelerator to compress the electron bunch length in stages. In these bunch compressors, coherent synchrotron radiation (CSR) can be emitted either by a short electron bunch or by any longitudinal density modulation that may be on the bunch. In this paper, we report detailed measurements of the CSR-induced energy loss and transverse emittance growth in these compressors. Good agreement is found between the experimental results and multiparticle tracking studies. We also describe direct observations of CSR at optical wavelengths and compare with analytical models based on beam microbunching.

  1. Recommended Practice for Securing Control System Modems

    Energy Technology Data Exchange (ETDEWEB)

    James R. Davidson; Jason L. Wright

    2008-01-01

    This paper addresses an often overlooked “backdoor” into critical infrastructure control systems created by modem connections. A modem’s connection to the public telephone system is similar to a corporate network connection to the Internet. By tracing typical attack paths into the system, this paper provides the reader with an analysis of the problem and then guides the reader through methods to evaluate existing modem security. Following the analysis, a series of methods for securing modems is provided. These methods are correlated to well-known networking security methods.

  2. Low level RF systems for synchrotrons part II: High Intensity. Compensation of the beam induced effects

    CERN Document Server

    Baudrenghien, P

    2005-01-01

    The high intensity regime is reached when the voltage induced by the beam in the RF cavities is of an amplitude comparable to the desired accelerating voltage. In steady state this beam loading can be compensated by providing extra RF power. Transient beam loading occurs at injection or in the presence of a beam intensity that is not uniform around the ring. The transients are periodic at the revolution frequency. Without correction transient beam loading can be very harmful: The stable phase and bucket area will not be equal for all bunches. Strong beam loading often goes in pair with longitudinal instabilities because the RF cavities are a large contributor to the total ring impedance. The low level systems that reduce the effect of the transient beam loading will also increase the threshold intensity of the longitudinal instability caused by the cavity impedance at the fundamental RF frequency. Four classic methods are presented here: Feedforward, RF feedback, long delay feedback and bunch by bunch feedbac...

  3. A data acquisition system for longitudinal beam properties in a rapid cycling synchrotron

    CERN Document Server

    Steimel, J

    2012-01-01

    A longitudinal beam properties, data acquisition system has been commissioned to operate in the Fermilab booster ring. This system captures real time information including beam synchronous phase, bunch length, and coupled bunch instability amplitudes as the beam is accelerated from 400 MeV to 8 GeV in 33 ms. The system uses an off-the-shelf Tektronix oscilloscope running Labview software and a synchronous pulse generator. This paper describes the hardware configuration and the software configuration used to optimize the data processing rate.

  4. Optimal energy for cell radiosensitivity enhancement by gold nanoparticles using synchrotron-based monoenergetic photon beams

    Directory of Open Access Journals (Sweden)

    Rahman WN

    2014-05-01

    Full Text Available Wan Nordiana Rahman,1,2 Stéphanie Corde,3,4 Naoto Yagi,5 Siti Aishah Abdul Aziz,1 Nathan Annabell,2 Moshi Geso21School of Health Sciences, Universiti Sains Malaysia, Kelantan, Malaysia; 2Division of Medical Radiation, School of Medical Sciences, Royal Melbourne Institute of Technology, Bundoora, VIC, 3Radiation Oncology, Prince of Wales Hospital, High Street, Randwick, 4Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia; 5Japanese Synchrotron Radiation Research Institute, Sayo-gun, Hyogo, JapanAbstract: Gold nanoparticles have been shown to enhance radiation doses delivered to biological targets due to the high absorption coefficient of gold atoms, stemming from their high atomic number (Z and physical density. These properties significantly increase the likelihood of photoelectric effects and Compton scattering interactions. Gold nanoparticles are a novel radiosensitizing agent that can potentially be used to increase the effectiveness of current radiation therapy techniques and improve the diagnosis and treatment of cancer. However, the optimum radiosensitization effect of gold nanoparticles is strongly dependent on photon energy, which theoretically is predicted to occur in the kilovoltage range of energy. In this research, synchrotron-generated monoenergetic X-rays in the 30–100 keV range were used to investigate the energy dependence of radiosensitization by gold nanoparticles and also to determine the photon energy that produces optimum effects. This investigation was conducted using cells in culture to measure dose enhancement. Bovine aortic endothelial cells with and without gold nanoparticles were irradiated with X-rays at energies of 30, 40, 50, 60, 70, 81, and 100 keV. Trypan blue exclusion assays were performed after irradiation to determine cell viability. Cell radiosensitivity enhancement was indicated by the dose enhancement factor which was found to be maximum at 40 keV with a value of 3

  5. ATDRSS 300 MB/S modem program

    Science.gov (United States)

    Ryan, Carl R.

    1992-01-01

    The 300 Mbps modem was developed for direct application to the next generation high data rate Time Division Multiple Access (TDMA) communication system. This modem utilizes continuous phase modulation combined with a restricted range Reed-Solomon Codec to achieve a bandwidth efficiency of 3 bits/sec/hz. The constant envelope amplitude signal allows one to operate the power amplifier in its saturation mode without significant spectral regrowth or bit error rate degradation.

  6. Realistic RF system and Beam Simulation in Real Time for a Synchrotron

    CERN Document Server

    Tückmantel, Joachim

    2001-01-01

    Due to heavy beam loading with gaps in the LHC beams, RF and beam are intimately linked to a complex system with fast transients where the RF loops and their limitations play a decisive role. Such a system is difficult to assess with analytical methods. To learn about overall system stability and for the definition of RF components to be built it is essential to understand the complete system long before the machine really exists. Therefore the author has written a general purpose real time simulation program and applied it to model the LHC machine with its beam pattern and complete double RF system. The latter is equipped with fast RF vector feedback loops having loop delay, transmitter power limitation and limited amplifier bandwidth as well as including one-turn-delay feedback and longitudinal batch injection damping. The development of all RF and beam quantities can be displayed graphically turn by turn. These frames can be assembled to a realistic multi-trace scope movie.

  7. High-speed, two-dimensional synchrotron white-beam x-ray radiography of spray breakup and atomization.

    Science.gov (United States)

    Halls, Benjamin R; Radke, Christopher D; Reuter, Benjamin J; Kastengren, Alan L; Gord, James R; Meyer, Terrence R

    2017-01-23

    High-speed, two-dimensional synchrotron x-ray radiography and phase-contrast imaging are demonstrated in propulsion sprays. Measurements are performed at the 7-BM beamline at the Advanced Photon Source user facility at Argonne National Laboratory using a recently developed broadband x-ray white beam. This novel enhancement allows for high speed, high fidelity x-ray imaging for the community at large. Quantitative path-integrated liquid distributions and spatio-temporal dynamics of the sprays were imaged with a LuAG:Ce scintillator optically coupled to a high-speed CMOS camera. Images are collected with a microscope objective at frame rates of 20 kHz and with a macro lens at 120 kHz, achieving spatial resolutions of 12 μm and 65 μm, respectively. Imaging with and without potassium iodide (KI) as a contrast-enhancing agent is compared, and the effects of broadband attenuation and spatial beam characteristics are determined through modeling and experimental calibration. In addition, phase contrast is used to differentiate liquid streams with varying concentrations of KI. The experimental approach is applied to different spray conditions, including quantitative measurements of mass distribution during primary atomization and qualitative visualization of turbulent binary fluid mixing.

  8. Digital Beam Trajectory and Orbit System, for the CERN Proton Synchrotron

    CERN Document Server

    Kasprowicz, G; Raich, U

    2008-01-01

    A new trajectory and orbit measurement system using fast signal sampling and digital signal processing in an FPGA is proposed for the CERN PS. The system uses a constant sampling frequency while the beam revolution frequency changes during acceleration. Synchronization with the beam is accomplished through a numerical PLL algorithm. This algorithm is also capable of treating RF gymnastics like bunch splitting or batch compression with the help of external timing signals. Baseline and position calculation are provided in the FPGA code as well. After having implemented the algorithms in C and MatLab and tested them with data from a test run at the PS, they have now been implemented in the FPGA for online use. Results of measurements on a single beam position monitor in the CERN PS and the SIS-18 at GSI will be presented.

  9. Development of a silicon microstrip detector with single photon sensitivity for fast dynamic diffraction experiments at a synchrotron radiation beam

    Science.gov (United States)

    Arakcheev, A.; Aulchenko, V.; Kudashkin, D.; Shekhtman, L.; Tolochko, B.; Zhulanov, V.

    2017-06-01

    Time-resolved experiments on the diffraction of synchrotron radiation (SR) from crystalline materials provide information on the evolution of a material structure after a heat, electron beam or plasma interaction with a sample under study. Changes in the material structure happen within a microsecond scale and a detector with corresponding parameters is needed. The SR channel 8 of the VEPP-4M storage ring provides radiation from the 7-pole wiggler that allows to reach several tens photons within one μs from a tungsten crystal for the most intensive diffraction peak. In order to perform experiments that allow to measure the evolution of tungsten crystalline structure under the impact of powerful laser beam, a new detector is developed, that can provide information about the distribution of a scattered SR flux in space and its evolution in time at a microsecond scale. The detector is based on the silicon p-in-n microstrip sensor with DC-coupled metal strips. The sensor contains 1024 30 mm long strips with a 50 μm pitch. 64 strips are bonded to the front-end electronics based on APC128 ASICs. The APC128 ASIC contains 128 channels that consist of a low noise integrator with 32 analogue memory cells each. The integrator equivalent noise charge is about 2000 electrons and thus the signal from individual photons with energy above 40 keV can be observed. The signal can be stored at the analogue memory with 10 MHz rate. The first measurements with the beam scattered from a tungsten crystal with energy near 60 keV demonstrated the capability of this prototype to observe the spatial distribution of the photon flux with the intensity from below one photon per channel up to 0~10 photons per channel with a frame rate from 10 kHz up to 1 MHz.

  10. Raster-scanning serial protein crystallography using micro- and nano-focused synchrotron beams

    Energy Technology Data Exchange (ETDEWEB)

    Coquelle, Nicolas [Université Grenoble Alpes, IBS, 38044 Grenoble (France); CNRS, IBS, 38044 Grenoble (France); CEA, IBS, 38044 Grenoble (France); Brewster, Aaron S. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Kapp, Ulrike; Shilova, Anastasya; Weinhausen, Britta [European Synchrotron Radiation Facility, BP 220, 38043 Grenoble (France); Burghammer, Manfred, E-mail: burgham@esrf.fr [European Synchrotron Radiation Facility, BP 220, 38043 Grenoble (France); Ghent University, Ghent B-9000 (Belgium); Colletier, Jacques-Philippe, E-mail: burgham@esrf.fr [Université Grenoble Alpes, IBS, 38044 Grenoble (France); CNRS, IBS, 38044 Grenoble (France); CEA, IBS, 38044 Grenoble (France)

    2015-05-01

    A raster scanning serial protein crystallography approach is presented, that consumes as low ∼200–700 nl of sedimented crystals. New serial data pre-analysis software, NanoPeakCell, is introduced. High-resolution structural information was obtained from lysozyme microcrystals (20 µm in the largest dimension) using raster-scanning serial protein crystallography on micro- and nano-focused beamlines at the ESRF. Data were collected at room temperature (RT) from crystals sandwiched between two silicon nitride wafers, thereby preventing their drying, while limiting background scattering and sample consumption. In order to identify crystal hits, new multi-processing and GUI-driven Python-based pre-analysis software was developed, named NanoPeakCell, that was able to read data from a variety of crystallographic image formats. Further data processing was carried out using CrystFEL, and the resultant structures were refined to 1.7 Å resolution. The data demonstrate the feasibility of RT raster-scanning serial micro- and nano-protein crystallography at synchrotrons and validate it as an alternative approach for the collection of high-resolution structural data from micro-sized crystals. Advantages of the proposed approach are its thriftiness, its handling-free nature, the reduced amount of sample required, the adjustable hit rate, the high indexing rate and the minimization of background scattering.

  11. Synchrotron and ion beam studies of the bone-cartilage interface

    Science.gov (United States)

    Bradley, D. A.; Kaabar, W.; Gundogdu, O.; Farquharson, M. J.; Janousch, M.; Bailey, M.; Jeynes, C.

    2010-07-01

    The divalent cations Ca, P and Zn have been reported to play an important role in the normal growth and remodelling of articular cartilage and subchondral bone and in the degenerative and inflammatory processes associated with osteoarthritis (OA). In particular, they act as co-factors of a class of enzymes known as metalloproteinases, believed to be active during the initiation, progress and remodelling processes associated with the disease. The relative presence of cations and anions, in particular the ions Na 2+ and Cl -, is also intimately associated with the fixed charge density (FCD) of cartilage, neutralizing the highly charged structure associated with for instance chondroitin sulphate. Finally, structural components of bone can be expected to result from dietary intake, yielding for instance strontium apatite and fluorapatite that form inclusions in the calcium hydroxyapatite of bone. In the present investigation, thin sections of articular cartilage affected by OA have been examined using a combination of physical techniques: low energy synchrotron micro X-ray fluorescence (μ-SXRF), micro proton induced X-ray emission (μ-PIXE) and micro proton-induced gamma emission (μ-PIGE), primarily to investigate the distribution of essential cations and anions. The combination of these physical techniques offers the ability to make comprehensive assessment of the elemental content of such tissues, simultaneous mappings of a range of relatively low atomic number ions being obtained over quite large areas (˜few mm 2). Such capability has only become a realistic prospect in recent times.

  12. Raster-scanning serial protein crystallography using micro- and nano-focused synchrotron beams.

    Science.gov (United States)

    Coquelle, Nicolas; Brewster, Aaron S; Kapp, Ulrike; Shilova, Anastasya; Weinhausen, Britta; Burghammer, Manfred; Colletier, Jacques Philippe

    2015-05-01

    High-resolution structural information was obtained from lysozyme microcrystals (20 µm in the largest dimension) using raster-scanning serial protein crystallography on micro- and nano-focused beamlines at the ESRF. Data were collected at room temperature (RT) from crystals sandwiched between two silicon nitride wafers, thereby preventing their drying, while limiting background scattering and sample consumption. In order to identify crystal hits, new multi-processing and GUI-driven Python-based pre-analysis software was developed, named NanoPeakCell, that was able to read data from a variety of crystallographic image formats. Further data processing was carried out using CrystFEL, and the resultant structures were refined to 1.7 Å resolution. The data demonstrate the feasibility of RT raster-scanning serial micro- and nano-protein crystallography at synchrotrons and validate it as an alternative approach for the collection of high-resolution structural data from micro-sized crystals. Advantages of the proposed approach are its thriftiness, its handling-free nature, the reduced amount of sample required, the adjustable hit rate, the high indexing rate and the minimization of background scattering.

  13. Synchrotron and ion beam studies of the bone-cartilage interface

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.A., E-mail: d.a.bradley@surrey.ac.u [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Kaabar, W.; Gundogdu, O. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Farquharson, M.J. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1 (Canada); Janousch, M. [Swiss Light Source, Paul Scherrer Institute, 5232 Villigen (Switzerland); Bailey, M.; Jeynes, C. [Surrey Ion Beam Centre, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2010-07-21

    The divalent cations Ca, P and Zn have been reported to play an important role in the normal growth and remodelling of articular cartilage and subchondral bone and in the degenerative and inflammatory processes associated with osteoarthritis (OA). In particular, they act as co-factors of a class of enzymes known as metalloproteinases, believed to be active during the initiation, progress and remodelling processes associated with the disease. The relative presence of cations and anions, in particular the ions Na{sup 2+} and Cl{sup -}, is also intimately associated with the fixed charge density (FCD) of cartilage, neutralizing the highly charged structure associated with for instance chondroitin sulphate. Finally, structural components of bone can be expected to result from dietary intake, yielding for instance strontium apatite and fluorapatite that form inclusions in the calcium hydroxyapatite of bone. In the present investigation, thin sections of articular cartilage affected by OA have been examined using a combination of physical techniques: low energy synchrotron micro X-ray fluorescence ({mu}-SXRF), micro proton induced X-ray emission ({mu}-PIXE) and micro proton-induced gamma emission ({mu}-PIGE), primarily to investigate the distribution of essential cations and anions. The combination of these physical techniques offers the ability to make comprehensive assessment of the elemental content of such tissues, simultaneous mappings of a range of relatively low atomic number ions being obtained over quite large areas ({approx}few mm{sup 2}). Such capability has only become a realistic prospect in recent times.

  14. Rematching AGS Booster synchrotron injection lattice for smaller transverse beam emittances

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Beebe-Wang, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brown, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gardner, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zeno, K. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-01-25

    The polarized proton beam is injected into the booster via the charge-exchange (H- to H+) scheme. The emittance growth due to scattering at the stripping foil is proportional to the beta functions at the foil. It was demonstrated that the current scheme of reducing the beta functions at the stripping foil preserves the emittance better; however the betatron tunes are above but very close to half integer. Due to concern of space charge and half integer in general, options of lattice designs aimed towards reducing the beta functions at the stripping foil with tunes at more favorable places are explored.

  15. Transverse coherence properties of X-ray beams in third-generation synchrotron radiation sources

    CERN Document Server

    Geloni, Gianluca; Schneidmiller, Evgeni; Yurkov, Mikhail

    2008-01-01

    This article describes a complete theory of spatial coherence for undulator radiation sources. Current estimations of coherence properties often assume that undulator sources are quasi-homogeneous, like thermal sources, and rely on the application of the van Cittert-Zernike theorem for calculating the degree of transverse coherence. Such assumption is not adequate when treating third generation light sources, because the vertical(geometrical) emittance of the electron beam is comparable or even much smaller than the radiation wavelength in a very wide spectral interval that spans over four orders of magnitude (from 0.1 Angstrom up to 10^3 Angstrom). Sometimes, the so-called Gaussian-Schell model, that is widely used in statistical optics in the description of partially-coherent sources, is applied as an alternative to the quasi-homogeneous model. However, as we will demonstrate, this model fails to properly describe coherent properties of X-ray beams from non-homogeneous undulator sources. As a result, a more...

  16. Mathematical Model of the Electronuclear Set-Up on the Beam of the JINR Synchrotron

    CERN Document Server

    Barashenkov, V S; Kumawat, H; Lobanova, V A

    2004-01-01

    On the base of the Monte Carlo code CASCADE, developed at JINR, a mathematical model of the deep-subcritical set-up with uranium blanket used in experiments underway at JINR using a 0.6-4 GeV proton beam, is created. The neutron spectra, yields and energies of generated particles are calculated and compared for several modifications of the set-up. The influence of paraffin and graphite moderators on the characteristics of particles escaping lead target is studied. The modelled set-up can be considered as a first step to experiments with the designed at JINR U-Pu ADS SAD with heat power of several tens of kW.

  17. Beam loss reduction by injection painting in the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

    Directory of Open Access Journals (Sweden)

    H. Hotchi

    2012-04-01

    Full Text Available The 3-GeV rapid cycling synchrotron (RCS of the Japan Proton Accelerator Research Complex was commissioned in October 2007. Via the initial beam tuning and a series of underlying beam studies with low-intensity beams, since December 2009, we have intermittently been performing beam tuning experiments with higher-intensity beams including the injection painting technique. By optimizing the injection painting parameters, we have successfully achieved a 420 kW-equivalent output intensity at a low-level intensity loss of less than 1%. Also the corresponding numerical simulation well reproduced the observed painting parameter dependence on the beam loss, and captured a characteristic behavior of the high-intensity beam in the injection painting process. In this paper, we present the experimental results obtained in the course of the RCS beam power ramp-up, especially on the beam loss reduction achieved by employing the injection painting, together with the numerical simulation results.

  18. Generating Picosecond X-Ray Pulses with Beam Manipulation in Synchrotron Light Sources

    CERN Document Server

    Guo, Weiming; Harkay, Katherine C; Sajaev, Vadim; Yang Bing Xin

    2005-01-01

    The length of x-ray pulses generated by storage ring light sources is usually tens of picoseconds. For example, the value is 40 ps rms at the Advanced Photon Source (APS). Methods of x-ray pulse compression are of great interest at the APS. One possible method, per Zholents et al., is to tilt the electron bunch with deflecting rf cavities.* Alternately, we found that the electron bunch can develop a tilt after application of a vertical kick in the presence of nonzero chromaticity. After slicing, the x-ray pulse length is determined by the tilt angle and the vertical beam size. In principal, sub-picosecond pulses can be obtained at APS. To date we have observed 6 ps rms visible light pulses with a streak camera. Efforts are underway to attempt further compression of the x-ray pulse and to increase the brilliance. This method can be easily applied to any storage ring light sources to generate x-ray pulses up to two orders of magnitude shorter than the electron bunch length. In this paper, we will present the th...

  19. I. THE THEORY OF ABERRATIONS OF QUADRUPOLE FOCUSING ARRAYS. II. ION OPTICAL DESIGN OF HIGH QUALITY EXTRACTED SYNCHROTRON BEAMS WITH APPLICATION TO THE BEVATRON

    Energy Technology Data Exchange (ETDEWEB)

    Meads Jr., Philip Francis

    1963-05-15

    In Part One they formulate in a general way the problem of analyzing and evaluating the aberrations of quadrupole magnet beam systems, and of characterizing the shapes and other properties of the beam envelopes in the neighborhood of foci. They consider all aberrations, including those due to misalignments and faulty construction, through third order in small parameters, for quadrupole beam systems. One result of this study is the development of analytic and numerical techniques for treating these aberrations, yielding useful expressions for the comparison of the aberrations of different beam systems. A second result of this study is a comprehensive digital computer program that determines the magnitude and nature of the aberrations of such beam systems. The code, using linear programming techniques, will adjust the parameters of a beam system to obtain specified optical properties and to reduce the magnitude of aberrations that limit the performance of that system. They examine numerically, in detail, the aberrations of two typical beam systems. In Part Two, they examine the problem of extracting the proton beam from a synchrotron of 'H' type magnet construction. They describe the optical studies that resulted in the design of an external beam from the Bevatron that is optimized with respect to linear, dispersive, and aberration properties and that uses beam elements of conservative design. The design of the beam is the result of the collaboration of many people representing several disciplines. They describe the digital computer programs developed to carry out detailed orbit studies which were required because of the existence of large second order aberrations in the beam.

  20. Nondestructive mapping of chemical composition and structural qualities of group III-nitride nanowires using submicron beam synchrotron-based X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Bonanno, P.L., E-mail: plb2@njit.edu [Georgia Institute of Technology/GTL, UMI 2958 Georgia Tech-CNRS, 57070 Metz (France); Gautier, S. [LMOPS + UMI: Laboratoire Matériaux Optiques, Photonique et micro-nano Systèmes, UMR CNRS 7132, Université de Metz et SUPELEC, 2 rue E. Belin, 57070 Metz, France, UMI 2958 Georgia Tech-CNRS, 57070 Metz (France); Gmili, Y.El.; Moudakir, T. [UMI 2958 Georgia Tech-CNRS, 57070 Metz (France); Sirenko, A.A. [Department of Physics, New Jersey Institute of Technology, Newark, NJ 07102 (United States); Kazimirov, A. [Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States); Cai, Z.-H. [Advanced Photon Source, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Martin, J. [LMOPS + UMI: Laboratoire Matériaux Optiques, Photonique et micro-nano Systèmes, UMR CNRS 7132, Université de Metz et SUPELEC, 2 rue E. Belin, 57070 Metz, France, UMI 2958 Georgia Tech-CNRS, 57070 Metz (France); Goh, W.H. [Georgia Institute of Technology/GTL, UMI 2958 Georgia Tech-CNRS, 57070 Metz (France); Martinez, A.; Ramdane, A.; Le Gratiet, L. [Laboratoire de Photonique et de Nanostructures, UPR CNRS 20, Route de Nozay, 91460 Marcoussis (France); Maloufi, N. [Laboratoire d' Etude des Textures et Application aux Matériaux UMR CNRS 7078 Ile du Saulcy 57045 METZ cedex 1 (France); Assouar, M.B. [Laboratoire de Physique des Milieux Ionisés et Applications, Nancy University, CNRS, BP 239, F-54506 Vandoeuvre-lès-Nancy Cédex (France); Ougazzaden, A. [Georgia Institute of Technology/GTL, UMI 2958 Georgia Tech-CNRS, 57070 Metz (France)

    2013-08-31

    Submicron beam synchrotron-based X-ray diffraction (XRD) techniques have been developed and used to accurately and nondestructively map chemical composition and material quality of selectively grown group III-nitride nanowires. GaN, AlGaN, and InGaN multi-quantum-well nanowires have been selectively grown on lattice matched and mismatched substrates, and the challenges associated with obtaining and interpreting submicron beam XRD results are addressed and solved. Nanoscale cathodoluminescence is used to examine exciton behavior, and energy-dispersive X-ray spectroscopy is used to verify chemical composition. Scanning transmission electron microscopy is later used to paint a more complete picture. The advantages of submicron beam XRD over other techniques are discussed in the context of this challenging material system. - Highlights: ► We used nano selective area growth to create nanowires of GaN, AlGaN and InGaN/GaN. ► We characterized them by synchrotron-based submicron beam X-ray diffraction (XRD). ► This technique accurately determined chemical and crystallographic properties. ► Challenges of XRD are addressed in the context of this challenging material system. ► Advantages of XRD over other characterization methods are discussed.

  1. A comparative study of high resolution cone beam X-ray tomography and synchrotron tomography applied to Fe- and Al-alloys.

    Science.gov (United States)

    Kastner, Johann; Harrer, Bernhard; Requena, Guillermo; Brunke, Oliver

    2010-10-01

    X-ray computed tomography (XCT) has become a very important method for non-destructive 3D-characterization and evaluation of materials. Due to measurement speed and quality, XCT systems with cone beam geometry and matrix detectors have gained general acceptance. Continuous improvements in the quality and performance of X-ray tubes and XCT devices have led to cone beam CT systems that can now achieve spatial resolutions down to 1 μm and even below. However, the polychromatic nature of the source, limited photon flux and cone beam artefacts mean that there are limits to the quality of the CT-data achievable; these limits are particularly pronounced with materials of higher density like metals. Synchrotron radiation offers significant advantages by its monochromatic and parallel beam of high brilliance. These advantages usually cause fewer artefacts, improved contrast and resolution.Tomography data of a steel sample and of two multi-phase Al-samples (AlSi12Ni1, AlMg5Si7) are recorded by advanced cone beam XCT-systems with a μ-focus (μXCT) and a sub-μm (nano-focus, sub-μXCT) X-ray source with voxel dimensions between 0.4 and 3.5 μm and are compared with synchrotron computed tomography (sXCT) with 0.3 μm/voxel. CT data features like beam hardening and ring artefacts, detection of details, sharpness, contrast, signal-to-noise ratio and the grey value histogram are systematically compared. In all cases μXCT displayed the lowest performance. Sub-μXCT gives excellent results in the detection of details, spatial and contrast resolution, which are comparable to synchrotron-XCT recordings. The signal-to-noise ratio is usually significantly lower for sub-μXCT compared with the two other methods. With regard to measurement costs "for industrial users", scanning volume, accessibility and user-friendliness sub-μXCT has significant advantages in comparison to synchrotron-XCT.

  2. Probing droplets with biological colloidal suspensions on smart surfaces by synchrotron radiation micro- and nano-beams

    KAUST Repository

    Marinaro, Giovanni

    2015-03-01

    Droplets with colloidal biological suspensions evaporating on substrates with defined wetting properties generate confined environments for initiating aggregation and self-assembly processes. We describe smart micro- and nanostructured surfaces, optimized for probing single droplets and residues by synchrotron radiation micro- and nanobeam diffraction techniques. Applications are presented for Ac-IVD and β-amyloid (1-42) peptides capable of forming cross-β sheet structures. Complementary synchrotron radiation FTIR microspectroscopy addresses secondary structure formation. The high synchrotron radiation source brilliance enables fast raster-scan experiments. © 2015 Elsevier Ltd.

  3. Probing droplets with biological colloidal suspensions on smart surfaces by synchrotron radiation micro- and nano-beams

    Science.gov (United States)

    Marinaro, G.; Accardo, A.; Benseny-Cases, N.; Burghammer, M.; Castillo-Michel, H.; Cotte, M.; Dante, S.; De Angelis, F.; Di Cola, E.; Di Fabrizio, E.; Hauser, C.; Riekel, C.

    2016-01-01

    Droplets with colloidal biological suspensions evaporating on substrates with defined wetting properties generate confined environments for initiating aggregation and self-assembly processes. We describe smart micro- and nanostructured surfaces, optimized for probing single droplets and residues by synchrotron radiation micro- and nanobeam diffraction techniques. Applications are presented for Ac-IVD and β-amyloid (1-42) peptides capable of forming cross-β sheet structures. Complementary synchrotron radiation FTIR microspectroscopy addresses secondary structure formation. The high synchrotron radiation source brilliance enables fast raster-scan experiments.

  4. Vertical beam size measurement in the CESR-TA $e^+e^-$ storage ring using x-rays from synchrotron radiation

    CERN Document Server

    Alexander, J P; Conolly, C; Edwards, E; Ehrlichman, M P; Fontes, E; Heltsley, B K; Hopkins, W; Lyndaker, A; Peterson, D P; Rider, N T; Rubin, D L; Savino, J; Seeley, R; Shanks, J; Flanagan, J W

    2013-01-01

    We describe the construction and operation of an x-ray beam size monitor (xBSM), a device measuring $e^+$ and $e^-$ beam sizes in the CESR-TA storage ring using synchrotron radiation. The device can measure vertical beam sizes of $10-100~\\mu$m on a turn-by-turn, bunch-by-bunch basis at $e^\\pm$ beam energies of $\\sim2~$GeV. At such beam energies the xBSM images x-rays of $\\epsilon\\approx$1-10$~$keV ($\\lambda\\approx 0.1-1$ nm) that emerge from a hard-bend magnet through a single- or multiple-slit (coded aperture) optical element onto an array of 32 InGaAs photodiodes with 50$~\\mu$m pitch. Beamlines and detectors are entirely in-vacuum, enabling single-shot beam size measurement down to below 0.1$~$mA ($2.5\\times10^9$ particles) per bunch and inter-bunch spacing of as little as 4$~$ns. At $E_{\\rm b}=2.1 $GeV, systematic precision of $\\sim 1~\\mu$m is achieved for a beam size of $\\sim12~\\mu$m; this is expected to scale as $\\propto 1/\\sigma_{\\rm b}$ and $\\propto 1/E_{\\rm b}$. Achieving this precision requires compr...

  5. A chirp modem incorporating interference excision

    Science.gov (United States)

    Darbyshire, E. P.; Gott, G. F.

    1992-08-01

    The paper describes an experimental 75-baud chirp modem designed to operate at high frequency (HF), which is able to reject interference from other HF users by adaptive filtering at the receiver. It also has inherently good performance in multipath preparation and in white noise, and is thus capable of robust digital communication. The system has been tested over a 170 km point-to-point HF skywave link, in which short chirp messages (approximately 30 s duration) were alternated in time with frequency-exchange keyed (FEK) messages. The total duration of the tests was 72 hours, and included day and night operation. In these tests, the chirp system had an overall performance which was superior to that of FEK. FEK occasionally suffered from long periods (e.g., 1 hour) of severe failure, essentially due to interference, whereas the chirp modem achieved more continuous useful operation.

  6. Home Security System Using Gsm Modem

    Directory of Open Access Journals (Sweden)

    Mehek Potnis

    2015-04-01

    Full Text Available This paper mainly focuses on using wireless technology effectively for security. The system is SMS-based and uses wireless technology to revolutionize the standards of living. It uses a GSM Modem to send an SMS to the home owner in case of an intrusion. The project is realized by interfacing an infrared trans-receiver with an ATMEGA16 microcontroller and a GSM Module. As the system uses GSM technology, it provides ubiquitous access to the system for security.

  7. Verification of TG-61 dose for synchrotron-produced monochromatic x-ray beams using fluence-normalized MCNP5 calculations

    CERN Document Server

    Brown, Thomas A D; Alvarez, Diane; Matthews, Kenneth L; Ham, Kyungmin; 10.1118/1.4761870

    2012-01-01

    Ion chamber dosimetry is being used to calibrate dose for cell irradiations designed to investigate photoactivated Auger electron therapy at the Louisiana State University CAMD synchrotron facility. This study performed a dosimetry intercomparison for synchrotron-produced monochromatic x-ray beams at 25 and 35 keV. Ion chamber depth-dose measurements in a PMMA phantom were compared with the product of MCNP5 Monte Carlo calculations of dose per fluence and measured incident fluence. Monochromatic beams of 25 and 35 keV were generated on the tomography beamline at CAMD. A cylindrical, air-equivalent ion chamber was used to measure the ionization created in a 10x10x10-cm3 PMMA phantom for depths from 0.6 to 7.7 cm. The American Association of Physicists in Medicine TG-61 protocol was applied to convert measured ionization into dose. Photon fluence was determined using a NaI detector to make scattering measurements of the beam from a thin polyethylene target at angles 30 degrees to 60 degrees. Differential Compto...

  8. Hard alpha-keratin degradation inside a tissue under high flux X-ray synchrotron micro-beam: a multi-scale time-resolved study.

    Science.gov (United States)

    Leccia, Emilie; Gourrier, Aurélien; Doucet, Jean; Briki, Fatma

    2010-04-01

    X-rays interact strongly with biological organisms. Synchrotron radiation sources deliver very intense X-ray photon fluxes within micro- or submicro cross-section beams, resulting in doses larger than the MGy. The relevance of synchrotron radiation analyses of biological materials is therefore questionable since such doses, million times higher than the ones used in radiotherapy, can cause huge damages in tissues, with regard to not only DNA, but also proteic and lipid organizations. Very few data concerning the effect of very high X-ray doses in tissues are available in the literature. We present here an analysis of the structural phenomena which occur when the model tissue of human hair is irradiated by a synchrotron X-ray micro-beam. The choice of hair is supported by its hierarchical and partially ordered keratin structure which can be analysed inside the tissue by X-ray diffraction. To assess the damages caused by hard X-ray micro-beams (1 microm(2) cross-section), short exposure time scattering SAXS/WAXS patterns have been recorded at beamline ID13 (ESRF) after various irradiation times. Various modifications of the scattering patterns are observed, they provide fine insight of the radiation damages at various hierarchical levels and also unexpectedly provide information about the stability of the various hierarchical structural levels. It appears that the molecular level, i.e. the alpha helices which are stabilized by hydrogen bonds and the alpha-helical coiled coils which are stabilized by hydrophobic interactions, is more sensitive to radiation than the supramolecular architecture of the keratin filament and the filament packing within the keratin associated proteins matrix, which is stabilized by disulphide bonds.

  9. Beam-loss induced pressure rise of Large Hadron Collider collimator materials irradiated with 158 GeV/u $In^{49+}$ ions at the CERN Super Proton Synchrotron

    CERN Document Server

    Mahner, Edgar; Hansen, Jan; Page, Eric; Vincke, H

    2004-01-01

    During heavy ion operation, large pressure rises, up to a few orders of magnitude, were observed at CERN, GSI, and BNL. The dynamic pressure rises were triggered by lost beam ions that impacted onto the vacuum chamber walls and desorbed about 10/sup 4/ to 10/sup 7/ molecules per ion. The deterioration of the dynamic vacuum conditions can enhance charge-exchange beam losses and can lead to beam instabilities or even to beam abortion triggered by vacuum interlocks. Consequently, a dedicated measurement of heavy-ion induced molecular desorption in the GeV/u energy range is important for Large Hadron Collider (LHC) ion operation. In 2003, a desorption experiment was installed at the super proton synchrotron to measure the beam-loss induced pressure rise of potential LHC collimator materials. Samples of bare graphite, sputter coated (Cu, TiZrV) graphite, and 316 LN (low carbon with nitrogen) stainless steel were irradiated under grazing angle with 158 GeV/u indium ions. After a description of the new experimental ...

  10. Beam-loss induced pressure rise of Large Hadron Collider collimator materials irradiated with 158 GeV/u In49+ ions at the CERN Super Proton Synchrotron

    Science.gov (United States)

    Mahner, E.; Efthymiopoulos, I.; Hansen, J.; Page, E.; Vincke, H.

    2004-10-01

    During heavy ion operation, large pressure rises, up to a few orders of magnitude, were observed at CERN, GSI, and BNL. The dynamic pressure rises were triggered by lost beam ions that impacted onto the vacuum chamber walls and desorbed about 104 to 107 molecules per ion. The deterioration of the dynamic vacuum conditions can enhance charge-exchange beam losses and can lead to beam instabilities or even to beam abortion triggered by vacuum interlocks. Consequently, a dedicated measurement of heavy-ion induced molecular desorption in the GeV/u energy range is important for Large Hadron Collider (LHC) ion operation. In 2003, a desorption experiment was installed at the Super Proton Synchrotron to measure the beam-loss induced pressure rise of potential LHC collimator materials. Samples of bare graphite, sputter coated (Cu, TiZrV) graphite, and 316LN (low carbon with nitrogen) stainless steel were irradiated under grazing angle with 158 GeV/u indium ions. After a description of the new experimental setup, the results of the pressure rise measurements are presented, and the derived desorption yields are compared with data from other experiments.

  11. Interaction of Super Proton Synchrotron beam with solid copper target: Simulations of future experiments at HiRadMat facility at CERN

    CERN Document Server

    Tahir, N A; Brugger, M; Assmann, R; Shutov, A; Lomonosov, I V; Fortov, V E; Piriz, A R; Deutsch, C; Hoffmann, D H H

    2009-01-01

    In this paper we present numerical simulations of interaction of 450 GeV/c proton beam that is generated by Super Proton Synchrotron (SPS) at CERN, with a solid copper target. These simulations have been carried out using a two-dimensional hydrodynamic computer code, BIG2. This study has been done to assess the damage caused by these highly relativistic protons to equipment including collimators, absorbers and others in case of an uncontrolled accidental release of the beam. In fact a dedicated experimental facility named HiRadMat is under construction at CERN that will allow one to study these problems experimentally. The simulations presented in this paper will be very useful in designing these experiments and later to interpret the experimental results.

  12. Dose-response curve of EBT, EBT2, and EBT3 radiochromic films to synchrotron-produced monochromatic x-ray beams

    CERN Document Server

    Brown, Thomas A D; Alvarez, Diane; Matthews, Kenneth L; Ham, Kyungmin; Dugas, Joseph P; 10.1118/1.4767770

    2012-01-01

    This work investigates the dose-response curves of GAFCHROMIC EBT, EBT2, and EBT3 radiochromic films using synchrotron-produced monochromatic x-ray beams. EBT2 film is being utilized for dose verification in photoactivated Auger electron therapy at the Louisiana State University CAMD synchrotron facility. Monochromatic beams of 25, 30, and 35 keV were generated on the tomography beamline at CAMD. Ion chamber depth-dose measurements were used to determine the dose delivered to films irradiated at depths from 0.7 to 8.5 cm in a 10x10x10-cm3 PMMA phantom. AAPM TG-61 protocol was applied to convert measured ionization into dose. Films were digitized using an Epson 1680 Professional flatbed scanner and analyzed using the net optical density (NOD) derived from the red channel. A dose-response curve was obtained at 35 keV for EBT film, and at 25, 30, and 35 keV for EBT2 and EBT3 films. Calibrations of films for 4 MV x-rays were obtained for comparison using a radiotherapy accelerator at Mary Bird Perkins Cancer Cent...

  13. 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.

  14. 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.

  15. Multiuser Receiver Architectures for Space Modems

    Science.gov (United States)

    Bell, D.; Satorius, E.; Kuperman, I.; Koenig, J.

    2014-08-01

    In this article, we develop multiuser modem architectures suitable for augmentation of existing software-defined flight radios with important near-term enhancements to relay telecom services as well as support for missions requiring entry, descent, and landing (EDL). EDL support for missions like Mars Exploration Rover (MER), Phoenix, Mars Science Laboratory (MSL), and Mars 2020 obtains strong visibility within JPL and NASA headquarters. As part of an agency-wide commitment to support EDL, funding has been made available on past missions to prepare multiple Deep Space Network (DSN) ground station sites, non-DSN ground stations (Greenbank 100-m), and to prioritize in situ coverage from multiple orbiters. Multiuser operations open up new possibilities for simultaneous support of multiple surface landers that are in close proximity such that these surface elements simultaneously appear in the same coverage circle of a single relay orbiter. Simultaneous multiuser support is an important service type for many future surface mission paradigms. In this article, designs for field-programmable gate array (FPGA) implementation of multiuser modems are presented. A fixed-point model of the most promising architecture for space applications is presented as well as simulated performance results based on a fixed-point design that is suitable for FPGA implementation.

  16. Synchrotron-based multiple-beam FTIR chemical imaging of a multi-layered polymer in transmission and reflection: towards cultural heritage applications

    Science.gov (United States)

    Unger, Miriam; Mattson, Eric; Schmidt Patterson, Catherine; Alavi, Zahrasadet; Carson, David; Hirschmugl, Carol J.

    2013-04-01

    IRENI (infrared environmental imaging) is a recently commissioned Fourier transform infrared (FTIR) chemical imaging beamline at the Synchrotron Radiation Center in Madison, WI, USA. This novel beamline extracts 320 mrad of radiation, horizontally, from one bending magnet. The optical transport separates and recombines the beam into 12 parallel collimated beams to illuminate a commercial FTIR microspectrometer (Bruker Hyperion 3000) equipped with a focal plane array detector where single pixels in the detector image a projected sample area of either 0.54×0.54 μm2 or 2×2 μm2, depending in the measurement geometry. The 12 beams are partially overlapped and defocused, similar to wide-field microscopy, homogeneously illuminating a relatively large sample area compared to single-beam arrangements. Both transmission and reflection geometries are used to examine a model cross section from a layered polymer material. The compromises for sample preparation and measurement strategies are discussed, and the chemical composition and spatial definition of the layers are distinguished in chemical images generated from data sets. Deconvolution methods that may allow more detailed data analysis are also discussed.

  17. Mitigating Doppler shift effect in HF multitone data modem

    Science.gov (United States)

    Sonlu, Yasar

    1989-09-01

    Digital communications over High Frequency (HF) radio channels are getting important in recent years. Current HF requirements are for data transmission at rates 2.4 kbps or more to accommodate computer data links and digital secure voice. HF modems which were produced to meet these speeds are, serial modems and parallel modems. On the other hand, the HF sky-wave communication medium, the ionosphere, has some propagation problems such as multipath and Doppler shift. The effect of Doppler shift in a parallel modem which employs Differential Quadrature Phase Shift Keying (DQPSK) modulation is considered and a correction method to mitigate the Doppler Shift effect is introduced.

  18. Effectiveness of respiratory-gated radiotherapy with audio-visual biofeedback for synchrotron-based scanned heavy-ion beam delivery

    Science.gov (United States)

    He, Pengbo; Li, Qiang; Zhao, Ting; Liu, Xinguo; Dai, Zhongying; Ma, Yuanyuan

    2016-12-01

    A synchrotron-based heavy-ion accelerator operates in pulse mode at a low repetition rate that is comparable to a patient’s breathing rate. To overcome inefficiencies and interplay effects between the residual motion of the target and the scanned heavy-ion beam delivery process for conventional free breathing (FB)-based gating therapy, a novel respiratory guidance method was developed to help patients synchronize their breathing patterns with the synchrotron excitation patterns by performing short breath holds with the aid of personalized audio-visual biofeedback (BFB) system. The purpose of this study was to evaluate the treatment precision, efficiency and reproducibility of the respiratory guidance method in scanned heavy-ion beam delivery mode. Using 96 breathing traces from eight healthy volunteers who were asked to breathe freely and guided to perform short breath holds with the aid of BFB, a series of dedicated four-dimensional dose calculations (4DDC) were performed on a geometric model which was developed assuming a linear relationship between external surrogate and internal tumor motions. The outcome of the 4DDCs was quantified in terms of the treatment time, dose-volume histograms (DVH) and dose homogeneity index. Our results show that with the respiratory guidance method the treatment efficiency increased by a factor of 2.23-3.94 compared with FB gating, depending on the duty cycle settings. The magnitude of dose inhomogeneity for the respiratory guidance methods was 7.5 times less than that of the non-gated irradiation, and good reproducibility of breathing guidance among different fractions was achieved. Thus, our study indicates that the respiratory guidance method not only improved the overall treatment efficiency of respiratory-gated scanned heavy-ion beam delivery, but also had the advantages of lower dose uncertainty and better reproducibility among fractions.

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

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, K.; Adams, F. [Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry; Rivers, M.L.; Jones, K.W. [Brookhaven National Lab., Upton, NY (United States)

    1992-10-01

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ({mu}-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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, K.; Adams, F. (Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry); Rivers, M.L.; Jones, K.W. (Brookhaven National Lab., Upton, NY (United States))

    1992-01-01

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ([mu]-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.

  1. A multiple CCD X-ray detector and its first operation with synchrotron radiation X-ray beam

    CERN Document Server

    Suzuki, M; Kumasaka, T; Sato, K; Toyokawa, H; Aries, I F; Jerram, P A; Ueki, T

    1999-01-01

    A 4x4 array structure of 16 identical CCD X-ray detector modules, called the multiple CCD X-ray detector system (MCCDX), was submitted to its first synchrotron radiation experiment at the protein crystallography station of the RIKEN beamline (BL45XU) at the SPring-8 facility. An X-ray diffraction pattern of cholesterol powder was specifically taken in order to investigate the overall system performance.

  2. 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.

  3. Dose-response curve of EBT, EBT2, and EBT3 radiochromic films to synchrotron-produced monochromatic x-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Thomas A. D.; Hogstrom, Kenneth R.; Alvarez, Diane; Matthews, Kenneth L. II; Ham, Kyungmin; Dugas, Joseph P. [Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809 and Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Center for Advanced Microstructures and Devices, Louisiana State University and A and M College, 6980 Jefferson Highway, Baton Rouge, Louisiana 70806 (United States); Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809 and Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States)

    2012-12-15

    Purpose: This work investigates the dose-response curves of GAFCHROMIC{sup Registered-Sign} EBT, EBT2, and EBT3 radiochromic films using synchrotron-produced monochromatic x-ray beams. EBT2 film is being utilized for dose verification in photoactivated Auger electron therapy at the Louisiana State University Center for Advanced Microstructures and Devices (CAMD) synchrotron facility. Methods: Monochromatic beams of 25, 30, and 35 keV were generated on the tomography beamline at CAMD. Ion chamber depth-dose measurements were used to determine the dose delivered to films irradiated at depths from 0.7 to 8.5 cm in a 10 Multiplication-Sign 10 Multiplication-Sign 10-cm{sup 3} polymethylmethacrylate phantom. AAPM TG-61 protocol was applied to convert measured ionization into dose. Films were digitized using an Epson 1680 Professional flatbed scanner and analyzed using the net optical density (NOD) derived from the red channel. A dose-response curve was obtained at 35 keV for EBT film, and at 25, 30, and 35 keV for EBT2 and EBT3 films. Calibrations of films for 4 MV x-rays were obtained for comparison using a radiotherapy accelerator at Mary Bird Perkins Cancer Center. Results: The sensitivity (NOD per unit dose) of EBT film at 35 keV relative to that for 4-MV x-rays was 0.73 and 0.76 for doses 50 and 100 cGy, respectively. The sensitivity of EBT2 film at 25, 30, and 35 keV relative to that for 4-MV x-rays varied from 1.09-1.07, 1.23-1.17, and 1.27-1.19 for doses 50-200 cGy, respectively. For EBT3 film the relative sensitivity was within 3% of unity for all three monochromatic x-ray beams. Conclusions: EBT and EBT2 film sensitivity showed strong energy dependence over an energy range of 25 keV-4 MV, although this dependence becomes weaker for larger doses. EBT3 film shows weak energy dependence, indicating that it would be a better dosimeter for kV x-ray beams where beam hardening effects can result in large changes in the effective energy.

  4. A feasibility study of dynamic stress analysis inside a running internal combustion engine using synchrotron X-ray beams.

    Science.gov (United States)

    Baimpas, Nikolaos; Drakopoulos, Michael; Connolley, Thomas; Song, Xu; Pandazaras, Costas; Korsunsky, Alexander M

    2013-03-01

    The present investigation establishes the feasibility of using synchrotron-generated X-ray beams for time-resolved in situ imaging and diffraction of the interior components of an internal combustion engine during its operation. The demonstration experiment was carried out on beamline I12 (JEEP) at Diamond Light Source, UK. The external hutch of the JEEP instrument is a large-scale engineering test bed for complex in situ processing and simulation experiments. The hutch incorporates a large capacity translation and rotation table and a selection of detectors for monochromatic and white-beam diffraction and imaging. These capabilities were used to record X-ray movies of a motorcycle internal combustion engine running at 1850 r.p.m. and to measure strain inside the connecting rod via stroboscopic X-ray diffraction measurement. The high penetrating ability and high flux of the X-ray beam at JEEP allowed the observation of inlet and outlet valve motion, as well as that of the piston, connecting rod and the timing chain within the engine. Finally, the dynamic internal strain within the moving connecting rod was evaluated with an accuracy of ~50 × 10(-6).

  5. LTE modem power consumption, SAR and RF signal strength emulation

    DEFF Research Database (Denmark)

    Musiige, Deogratius; Vincent, Laulagnet; Anton, François

    2012-01-01

    This paper presents a new methodology for emulating the LTE modem power consumption, emitted SAR and RF signal strength when transmitting an LTE signal. The inputs of the methodology are: modem logical/protocol commands, time advance, near-field specifier, and antenna characteristics. The power...

  6. X-ray study of a SODART flight telescope using the expanded beam x-ray optics beamline at the Daresbury synchrotron

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Frederiksen, P. K.;

    1995-01-01

    The on- and off-axis imaging properties of the first of two SODART flight telescopes have been studied using the expanded beam x-ray facility at the Daresbury synchrotron. From on- axis measurements the encircled power distribution and the point spread function at three energies 6.627 keV, 8.837 ke......V, and 11.046 keV have been measured using a one dimensional position sensitive detector. The data have been used to calculate the half power diameter (HPD) for three different SODART focal plane detectors, the high energy proportional counter (HEPC), the low energy proportional counter (LEPC) and the 19...... element solid state array detector (SIXA). We found that the HPD decreases with increasing energy due to poorer figure error of the outermost mirrors. The HPD falls in the range from 2.3 to 3 arcmin for all detectors. Residual misalignment of the individual quadrants of the telescope was found...

  7. X-ray study of a test quadrant of the SODART telescopes using the expanded beam x-ray optics facility at the Daresbury synchrotron

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Frederiksen, P.;

    1994-01-01

    The imaging properties of a test model of the SODART telescopes have been studied using an expanded beam X-ray facility at the Daresbury synchrotron. The encircled power and the point spread function at three energies 6.627 keV, 8.837 keV and 11.046 keV have been measured using 1D and 2D position......V the HPD is 2.5 - 3.0 arcmin for all detectors whereas it is somewhat larger at 11.046 keV for HEPC and LEPC but essentially unchanged for SIXA. Finally, the data are used to point to improvements that can be introduced during the manufacture of the flight telescopes....

  8. Concept of a Staged FEL Enabled by Fast Synchrotron Radiation Cooling of Laser-Plasma Accelerated Beam by Solenoidal Magnetic Fields in Plasma Bubble

    CERN Document Server

    Seryi, Andrei; Andreev, Alexander; Konoplev, Ivan

    2016-01-01

    A novel method for generating GigaGauss solenoidal field in laser-plasma bubble, using screw-shaped laser pulses, has been recently presented in arXiv:1604.01259 [physics.plasm-ph]. Such magnetic fields enable fast synchrotron radiation cooling of the beam emittance of laser-plasma accelerated leptons. This recent finding opens a novel approach for design of laser-plasma FELs or colliders, where the acceleration stages are interleaved with laser-plasma emittance cooling stages. In this concept paper we present an outline of how a staged plasma-acceleration FEL could look like and discuss further studies needed to investigate the feasibility of the concept in detail.

  9. Digital 8-DPSK Modem For Trellis-Coded Communication

    Science.gov (United States)

    Jedrey, T. C.; Lay, N. E.; Rafferty, W.

    1989-01-01

    Digital real-time modem processes octuple differential-phase-shift-keyed trellis-coded modulation. Intended for use in communicating data at rate up to 4.8 kb/s in land-mobile satellite channel (Rician fading) of 5-kHz bandwidth at carrier frequency of 1 to 2 GHz. Modulator and demodulator contain digital signal processors performing modem functions. Design flexible in that functions altered via software. Modem successfully tested and evaluated in both laboratory and field experiments, including recent full-scale satellite experiment. In all cases, modem performed within 1 dB of theory. Other communication systems benefitting from this type of modem include land mobile (without satellites), paging, digitized voice, and frequency-modulation subcarrier data broadcasting.

  10. FEC combined burst-modem for business satellite communications use

    Science.gov (United States)

    Murakami, K.; Miyake, M.; Fuji, T.; Moritani, Y.; Fujino, T.

    The authors recently developed two types of FEC (forward error correction) combined modems both applicable to low-data-rate and intermediate-data-rate TDMA international satellite communications. Each FEC combined modem consists of a QPSK (quadrature phase-shift keyed) modem, a convolutional encoder, and a Viterbi decoder. Both modems are designed taking into consideration the fast acquisition of the carrier and bit timing and the low cycle slipping rate in the low-carrier-to-noise-ratio environment. Attention is paid to designing the Viterbi decoder to be operated in a situation in which successive bursts may have different coding rates according to the punctured coding scheme. The overall scheme of the FEC combined modems are presented, and some of the key technologies applied in developing them are outlined. The hardware implementation and experimentation are also discussed. The measured data are compared with results of theoretical analysis, and relatively good performances are obtained.

  11. Impact of high energy high intensity proton beams on targets: Case studies for Super Proton Synchrotron and Large Hadron Collider

    CERN Document Server

    Tahir, N A; Shutov, A; Schmidt, R; Piriz, A R

    2012-01-01

    The Large Hadron Collider (LHC) is designed to collide two proton beams with unprecedented particle energy of 7 TeV. Each beam comprises 2808 bunches and the separation between two neighboring bunches is 25 ns. The energy stored in each beam is 362 MJ, sufficient to melt 500 kg copper. Safety of operation is very important when working with such powerful beams. An accidental release of even a very small fraction of the beam energy can result in severe damage to the equipment. The machine protection system is essential to handle all types of possible accidental hazards; however, it is important to know about possible consequences of failures. One of the critical failure scenarios is when the entire beam is lost at a single point. In this paper we present detailed numerical simulations of the full impact of one LHC beam on a cylindrical solid carbon target. First, the energy deposition by the protons is calculated with the FLUKA code and this energy deposition is used in the BIG2 code to study the corresponding...

  12. Non-Invasive Measurement of Emittance and Optical Parameters for High-Brightness Hadron Beams in a Synchrotron

    CERN Document Server

    Jansson, A

    2001-01-01

    For hadron colliders, such as the Large Hadron Collider at CERN, emittance preservation is of prime importance to achieve a high luminosity. Since there are no significant effects (apart from active cooling) that decrease the emittance of a hadron beam, the smallest possible emittance is set by the source, and has to be preserved along the entire injector chain. One possible source of emittance increase is due to optical mismatch at beam transfer between two machines in this chain. To verify the matching on-line requires a non-invasive instrument capable of measuring the optical parameters of the injected beam. Such instruments are very rare. A quadrupole pick-up is a non-invasive instrument sensitive to beam size. It is basically a beam position monitor, where the non-linear response to particle position is used to extract information on the second moment of the transverse beam distribution. The basic idea was proposed a long time ago, and have been successfully used at a few occasions, but have not found an...

  13. X-ray beam splitting design for concurrent imaging at hard X-ray FELs and synchrotron facilities

    Energy Technology Data Exchange (ETDEWEB)

    Oberta, P., E-mail: peter.oberta@rigaku.com [Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, Praha 8, CZ-18221 (Czech Republic); Rigaku, Novodvorská 994, Praha 4, CZ-14221 (Czech Republic); Mokso, R. [Swiss Light Source, Paul Scherrer Institut, Villigen, CH-5232 Villigen (Switzerland)

    2013-11-21

    A new configuration of diffractive–refractive optics for beam splitting is investigated. The set-up can be applied to perform imaging with two beams simultaneously. It brings advantages toward dynamic studies using image guided diffraction or fluorescence spectroscopy. The optimal energy range of operation for the beam-splitter is between 7 keV and 24 keV, reaching best efficiency at an energy of 10 keV. Due to the long focusing distances (several tens of meters) created by the diffractive–refractive optics and the higher refraction efficiency in the softer energy range, the presented set-ups are ideal for hard X-ray FEL sources.

  14. Respiratory motion management using audio-visual biofeedback for respiratory-gated radiotherapy of synchrotron-based pulsed heavy-ion beam delivery

    Energy Technology Data Exchange (ETDEWEB)

    He, Pengbo; Ma, Yuanyuan; Huang, Qiyan; Yan, Yuanlin [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); School of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Qiang, E-mail: liqiang@impcas.ac.cn; Liu, Xinguo; Dai, Zhongying; Zhao, Ting; Fu, Tingyan; Shen, Guosheng [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China)

    2014-11-01

    Purpose: To efficiently deliver respiratory-gated radiation during synchrotron-based pulsed heavy-ion radiotherapy, a novel respiratory guidance method combining a personalized audio-visual biofeedback (BFB) system, breath hold (BH), and synchrotron-based gating was designed to help patients synchronize their respiratory patterns with synchrotron pulses and to overcome typical limitations such as low efficiency, residual motion, and discomfort. Methods: In-house software was developed to acquire body surface marker positions and display BFB, gating signals, and real-time beam profiles on a LED screen. Patients were prompted to perform short BHs or short deep breath holds (SDBH) with the aid of BFB following a personalized standard BH/SDBH (stBH/stSDBH) guiding curve or their own representative BH/SDBH (reBH/reSDBH) guiding curve. A practical simulation was performed for a group of 15 volunteers to evaluate the feasibility and effectiveness of this method. Effective dose rates (EDRs), mean absolute errors between the guiding curves and the measured curves, and mean absolute deviations of the measured curves were obtained within 10%–50% duty cycles (DCs) that were synchronized with the synchrotron’s flat-top phase. Results: All maneuvers for an individual volunteer took approximately half an hour, and no one experienced discomfort during the maneuvers. Using the respiratory guidance methods, the magnitude of residual motion was almost ten times less than during nongated irradiation, and increases in the average effective dose rate by factors of 2.39–4.65, 2.39–4.59, 1.73–3.50, and 1.73–3.55 for the stBH, reBH, stSDBH, and reSDBH guiding maneuvers, respectively, were observed in contrast with conventional free breathing-based gated irradiation, depending on the respiratory-gated duty cycle settings. Conclusions: The proposed respiratory guidance method with personalized BFB was confirmed to be feasible in a group of volunteers. Increased effective dose

  15. Stress evaluation in thin films: Micro-focus synchrotron X-ray diffraction combined with focused ion beam patterning for d{sub o} evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Baimpas, Nikolaos, E-mail: nikolaos.baimpas@eng.ox.ac.uk [University of Oxford, Dept. of Engineering Science (United Kingdom); Le Bourhis, Eric [University of Poitiers, Institut P' , Laboratoire de Physique des Matériaux, Poitiers (France); Eve, Sophie [ENSICAEN, CRISMAT, Caen (France); Thiaudière, Dominique [Synchrotron SOLEIL, L' Orme des Merisiers Saint-Aubin, Paris (France); Hardie, Christopher [University of Oxford, Materials Department (United Kingdom); Korsunsky, Alexander M. [University of Oxford, Dept. of Engineering Science (United Kingdom)

    2013-12-31

    Nanocrystalline metallic coatings of sub-micron thickness are widely used in modern microelectronic applications. In X-ray diffraction experiments to determine both the residual and applied stresses in nanocrystalline coatings, one difficult challenge that comes up invariably is the determination of the strain-free lattice spacing d{sub o}. The present study addresses this challenge by using the focused ion beam (FIB) to generate a built-in strain-free reference by patterning (milling) a 50 × 50 μm{sup 2} region of the coating to produce an array of small stress-relieved “islands” ∼ 0.8 × 0.8 μm{sup 2} each. Transmission X-ray diffraction setup was used for data collection at DIFFABS beamline (Synchrotron SOLEIL, France). A 150 nm-thick multi-layered W–Cu nano-composite thin film on polyimide (Kapton®) substrate was studied. The samples were loaded incrementally using a compact uniaxial loading device, and micro-beam diffraction data were collected on and away from the reference array. It was shown experimentally that the “island” array remained approximately strain free throughout the experiment, providing an on-board d{sub o} lattice spacing reference. The changing lattice spacing d in the coating was also monitored away from the array, to deduce the elastic strain evolution during deformation. The results and their implications are presented and discussed. - Highlights: • In situ deformation study of laminate polycrystalline W–Cu thin films • Focused ion beam (FIB) patterning of an array of “islands” on thin films surface • X-ray diffraction on island-patterned region • Constant strain on “islands” independently of the deformation of the substrate.

  16. Neuropathology of ablation of rat gliosarcomas and contiguous brain tissues using a microplanar beam of synchrotron-wiggler-generated X rays.

    Science.gov (United States)

    Laissue, J A; Geiser, G; Spanne, P O; Dilmanian, F A; Gebbers, J O; Geiser, M; Wu, X Y; Makar, M S; Micca, P L; Nawrocky, M M; Joel, D D; Slatkin, D N

    1998-11-23

    Adult-rat-brain tissues display an unusually high resistance to necrosis when serially irradiated with parallel, thin slices of a microplanar (i.e., microscopically thin and macroscopically broad) beam of synchrotron-wiggler-generated, approx. 35-120 keV (median approx. 50 keV) Gd-filtered X rays at skin-entrance absorbed doses of 312 to 5000 Gy per slice. Such microplanar beams were used to irradiate young adult rats bearing right frontocerebral 9L gliosarcomas (approx. 4 mm diameter), through a volume of tissue containing the tumor and contiguous brain tissue, either in a single array or in 2 orthogonally crossed arrays of tissue slices. Each array included 101 parallel microplanar slices, 100 microm center-to-center distance, each slice being approx. 25 microm wide and 12 mm high, with skin-entrance absorbed doses of 312.5 Gy or 625 Gy per slice. Compared with unirradiated controls with a median survival time of 20 days after tumor initiation, the median survival time was extended in irradiated rats by 139 days (625 Gy, crossed arrays), 96 days (312 Gy, crossed arrays) or 24 days (625 Gy, single array). The tumors disappeared in 22 of the 36 irradiated rats, 4/11 even after unidirectional microbeam irradiation. The extent and severity of radiation damage to the normal brain in rats with or without tumor was graded histopathologically. Correlation of those grades with radiation doses shows that loss of tissue structure was confined to beam-crossing regions and that only minor damage was done to zones of the brain irradiated unidirectionally.

  17. Coherent Path Beamformer Front End for High Performance Acoustic Modems

    Science.gov (United States)

    1999-09-30

    data were transmitted using a standard AUV modem towed by a boat moving in a zig - zag pattern within a 120 degrees cone, at distances from 1km to 1.5...16kHz to 32kHz, using a 32 by 32 Mills -Cross array and a single-channel acoustic modem. The intents are to measure and characterize the underwater

  18. Analysis on Residual Stress in Electron Beam-Physical Vapor Deposited Thermal Barrier Coating using Hard Synchrotron X-Rays

    OpenAIRE

    鈴木, 賢治; 松本, 一秀; 久保, 貴博; 町屋, 修太郎; 田中, 啓介; 秋庭, 義明; SUZUKI, Kenji; MATSUMOTO, Kazuhide; Kubo, Takahiro; Machiya, Syutaro; Tanaka, Keisuke; Akiniwa, Yoshiaki

    2005-01-01

    The distribution of the residual stress in the thermal barrier coating, which was made by an electron beam-physical vapor deposition (EB-PVD) method, was determined using X-ray stress measurements. As the bond coating, NiCoCrAlY was low-pressure plasma sprayed on the substrate of austenitic stainless steel. The 8 mass% Y_2O_3-ZrO_2 was coated on the bond coating using the EB-PVD method as the top coating. The top coating had the preferred orientation with the axis direction perpendicular to ...

  19. Proton synchrotron radiation at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Thurman-Keup, Randy; /Fermilab

    2006-05-01

    While protons are not generally associated with synchrotron radiation, they do emit visible light at high enough energies. This paper presents an overview of the use of synchrotron radiation in the Tevatron to measure transverse emittances and to monitor the amount of beam in the abort gap. The latter is necessary to ensure a clean abort and prevent quenches of the superconducting magnets and damage to the silicon detectors of the collider experiments.

  20. Synchrotron X-ray studies of the keel of the short-spined sea urchin Lytechinus variegatus: absorption microtomography (microCT) and small beam diffraction mapping.

    Science.gov (United States)

    Stock, S R; Barss, J; Dahl, T; Veis, A; Almer, J D; Carlo, F

    2003-05-01

    In sea urchin teeth, the keel plays an important structural role, and this paper reports results of microstructural characterization of the keel of Lytechinus variegatus using two noninvasive synchrotron x-ray techniques: x-ray absorption microtomography (microCT) and x-ray diffraction mapping. MicroCT with 14 keV x-rays mapped the spatial distribution of mineral at the 1.3 microm level in a millimeter-sized fragment of a mature portion of the keel. Two rows of low absorption channels (i.e., primary channels) slightly less than 10 microm in diameter were found running linearly from the flange to the base of the keel and parallel to its sides. The primary channels paralleled the oral edge of the keel, and the microCT slices revealed a planar secondary channel leading from each primary channel to the side of the keel. The primary and secondary channels were more or less coplanar and may correspond to the soft tissue between plates of the carinar process. Transmission x-ray diffraction with 80.8 keV x-rays and a 0.1 mm beam mapped the distribution of calcite crystal orientations and the composition Ca(1-x)Mg(x)CO(3) of the calcite. Unlike the variable Mg concentration and highly curved prisms found in the keel of Paracentrotus lividus, a constant Mg content (x = 0.13) and relatively little prism curvature was found in the keel of Lytechinus variegatus.

  1. Characterization of grown-in dislocations in high-quality glucose isomerase crystals by synchrotron monochromatic-beam X-ray topography

    Science.gov (United States)

    Suzuki, Ryo; Koizumi, Haruhiko; Kojima, Kenichi; Fukuyama, Seijiro; Arai, Yasutomo; Tsukamoto, Katsuo; Suzuki, Yoshihisa; Tachibana, Masaru

    2017-06-01

    High quality glucose isomerase (GI) single crystals are grown by using chemical cross-linked seed crystals. The crystal structure is an orthorhombic system in which the molecular arrangement is close to a body-centered cubic (bcc) one. The crystal defects, especially dislocations, in GI crystals are experimentally characterized by synchrotron monochromatic-beam X-ray topography. Two straight dislocations are clearly observed, which originate from the interface between the cross-linked seed crystal and the grown crystal. From the invisibility criterion of the dislocation images, it is experimentally identified that they are close to be of pure edge character with the Burgers vector of [1 1 bar 1] which is typical one in bcc metal crystals. Moreover, bead-like contrasts along the dislocation images and the equal-thickness fringes, related to Pendellösung fringes, at crystal edges are clearly observed, which have never been observed in other protein crystals so far. These contrasts can attributed to the dynamical diffraction effect which has been often observed in high-quality crystals such as Si. Thus it seems that the perfection of GI crystals shown in this paper is extremely high compared with other protein crystals reported so far.

  2. Investigation of the Distribution of Elements in Snail Shell With the use of Synchrotron-Based, Micro-Beam X-ray Fluorescence Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Rao, D.; Swapna, M; Cesareo, R; Brunetti, A; Akatsuka, T; Yuasa, T; Takeda, T; Tromba, G; Gigante, G

    2009-01-01

    In this study, synchrotron-based micro-beam was utilized for elemental mapping of a small animal shell. A thin X-ray spot of the order of {approx}10 em was focused on the sample. With this spatial resolution and high flux throughput, the X-ray fluorescent intensities for Ca, Mn, Fe, Ni, Zn, Cr and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive HpGe detector. The sample is scanned in a estep-and-repeat' mode for fast elemental mapping and generated elemental maps at 8, 10 and 12 keV. All images are of 10 em resolution and the measurement time was 1 s per point. The accumulation of trace elements was investigated from the soft-tissue in small areas. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other trace elements.

  3. Design and implementation of an omni-directional underwater acoustic micro-modem based on a low-power micro-controller unit.

    Science.gov (United States)

    Won, Tae-Hee; Park, Sung-Joon

    2012-01-01

    For decades, underwater acoustic communication has been restricted to the point-to-point long distance applications such as deep sea probes and offshore oil fields. For this reason, previous acoustic modems were typically characterized by high data rates and long working ranges at the expense of large size and high power consumption. Recently, as the need for underwater wireless sensor networks (UWSNs) has increased, the research and development of compact and low-power consuming communication devices has become the focus. From the consideration that the requisites of acoustic modems for UWSNs are low power consumption, omni-directional beam pattern, low cost and so on, in this paper, we design and implement an omni-directional underwater acoustic micro-modem satisfying these requirements. In order to execute fast digital domain signal processing and support flexible interfaces with other peripherals, an ARM Cortex-M3 is embedded in the micro-modem. Also, for the realization of small and omni-directional properties, a spherical transducer having a resonant frequency of 70 kHz and a diameter of 34 mm is utilized for the implementation. Physical layer frame format and symbol structure for efficient packet-based underwater communication systems are also investigated. The developed acoustic micro-modem is verified analytically and experimentally in indoor and outdoor environments in terms of functionality and performance. Since the modem satisfies the requirements for use in UWSNs, it could be deployed in a wide range of applications requiring underwater acoustic communication.

  4. Design and Implementation of an Omni-Directional Underwater Acoustic Micro-Modem Based on a Low-Power Micro-Controller Unit

    Directory of Open Access Journals (Sweden)

    Sung-Joon Park

    2012-02-01

    Full Text Available For decades, underwater acoustic communication has been restricted to the point-to-point long distance applications such as deep sea probes and offshore oil fields. For this reason, previous acoustic modems were typically characterized by high data rates and long working ranges at the expense of large size and high power consumption. Recently, as the need for underwater wireless sensor networks (UWSNs has increased, the research and development of compact and low-power consuming communication devices has become the focus. From the consideration that the requisites of acoustic modems for UWSNs are low power consumption, omni-directional beam pattern, low cost and so on, in this paper, we design and implement an omni-directional underwater acoustic micro-modem satisfying these requirements. In order to execute fast digital domain signal processing and support flexible interfaces with other peripherals, an ARM Cortex-M3 is embedded in the micro-modem. Also, for the realization of small and omni-directional properties, a spherical transducer having a resonant frequency of 70 kHz and a diameter of 34 mm is utilized for the implementation. Physical layer frame format and symbol structure for efficient packet-based underwater communication systems are also investigated. The developed acoustic micro-modem is verified analytically and experimentally in indoor and outdoor environments in terms of functionality and performance. Since the modem satisfies the requirements for use in UWSNs, it could be deployed in a wide range of applications requiring underwater acoustic communication.

  5. Phase Transformations During Solidification of a Laser-Beam-Welded TiAl Alloy—An In Situ Synchrotron Study

    Science.gov (United States)

    Liu, Jie; Staron, Peter; Riekehr, Stefan; Stark, Andreas; Schell, Norbert; Huber, Norbert; Schreyer, Andreas; Müller, Martin; Kashaev, Nikolai

    2016-09-01

    An in situ highly time-resolved, high-energy X-ray diffraction investigation was carried out to observe the phase transformations of a TiAl alloy during laser beam welding. The diffraction patterns are recorded every 0.1 seconds by a fast area two-dimensional detector and plotted according to time, yielding the solidification pathway, the solid phase volume fraction, and the lattice parameter variation of different phases during the solidification and cooling process. Moreover, it is the first study that can demonstrate that the α phase without any Burgers orientation relationship, the so-called non-Burgers α, precipitates appear earlier than the Burgers α. The non-Burgers α grains are found to nucleate on the primary borides.

  6. SYNCHROTRON RADIATION SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  7. Synchrotron radiation in biosciences

    Science.gov (United States)

    Marinkovic, Nebojsa S.; Gupta, Sayan; Zhan, Chenyang; Chance, Mark R.

    2005-12-01

    The Center for Synchrotron Biosciences (CSB) operates five beamlines at the National Synchrotron Light Source (NSLS). Infrared (IR) micro-spectroscopy, X-ray absorption spectroscopy, structural proteomics and macromolecular footprinting are among the major technologies available through the Center. IR micro-spectroscopy is used to examine protein-folding in the microsecond time regime, image bone, neurons, seeds and other biological tissues, as well as image samples of interest in the chemical and environmental sciences. Structural proteomics research of New York Structural Genomics Research Consortium (NYSGRC) is steadily increasing the number of solved protein structures, with a goal to solve 100-200 structures per year. To speed up the research, a high-throughput method called 'metallomics' was implemented for NYSGRC crystallographers to detect intrinsic anomalous scatterers using X-ray absorption spectroscopy. Hydroxyl radical mediated X-ray footprinting is capable of resolving folding events of RNA, at single base resolution on millisecond timescales using a synchrotron white beam. The high brightness of synchrotron source is essential for CSB projects as it permits the use of smaller sample sizes and/or concentration, and allows studies of more complicated biological systems than with conventional sources.

  8. Synchrotron radiation in biosciences

    Energy Technology Data Exchange (ETDEWEB)

    Marinkovic, Nebojsa S. [Center for Synchrotron Biosciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Ullman 315, Bronx, NY 10461 (United States)]. E-mail: marinkov@bnl.gov; Gupta, Sayan [Center for Synchrotron Biosciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Ullman 315, Bronx, NY 10461 (United States); Zhan, Chenyang [Center for Synchrotron Biosciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Ullman 315, Bronx, NY 10461 (United States); Chance, Mark R. [Center for Synchrotron Biosciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Ullman 315, Bronx, NY 10461 (United States)

    2005-12-15

    The Center for Synchrotron Biosciences (CSB) operates five beamlines at the National Synchrotron Light Source (NSLS). Infrared (IR) micro-spectroscopy, X-ray absorption spectroscopy, structural proteomics and macromolecular footprinting are among the major technologies available through the Center. IR micro-spectroscopy is used to examine protein-folding in the microsecond time regime, image bone, neurons, seeds and other biological tissues, as well as image samples of interest in the chemical and environmental sciences. Structural proteomics research of New York Structural Genomics Research Consortium (NYSGRC) is steadily increasing the number of solved protein structures, with a goal to solve 100-200 structures per year. To speed up the research, a high-throughput method called 'metallomics' was implemented for NYSGRC crystallographers to detect intrinsic anomalous scatterers using X-ray absorption spectroscopy. Hydroxyl radical mediated X-ray footprinting is capable of resolving folding events of RNA, at single base resolution on millisecond timescales using a synchrotron white beam. The high brightness of synchrotron source is essential for CSB projects as it permits the use of smaller sample sizes and/or concentration, and allows studies of more complicated biological systems than with conventional sources.

  9. Evaluating the Effect of Processing Parameters on Porosity in Electron Beam Melted Ti-6Al-4V via Synchrotron X-ray Microtomography

    Science.gov (United States)

    Cunningham, Ross; Narra, Sneha P.; Ozturk, Tugce; Beuth, Jack; Rollett, A. D.

    2016-03-01

    Electron beam melting (EBM) is one of the subsets of direct metal additive manufacturing (AM), an emerging manufacturing method that fabricates metallic parts directly from a three-dimensional (3D) computer model by the successive melting of powder layers. This family of technologies has seen significant growth in recent years due to its potential to manufacture complex components with shorter lead times, reduced material waste and minimal post-processing as a "near-net-shape" process, making it of particular interest to the biomedical and aerospace industries. The popular titanium alloy Ti-6Al-4V has been the focus of multiple studies due to its importance to these two industries, which can be attributed to its high strength to weight ratio and corrosion resistance. While previous research has found that most tensile properties of EBM Ti-6Al-4V meet or exceed conventional manufacturing standards, fatigue properties have been consistently inferior due to a significant presence of porosity. Studies have shown that adjusting processing parameters can reduce overall porosity; however, they frequently utilize methods that give insufficient information to properly characterize the porosity (e.g., Archimedes' method). A more detailed examination of the result of process parameter adjustments on the size and spatial distribution of gas porosity was performed utilizing synchrotron-based x-ray microtomography with a minimum feature resolution of 1.5 µm. Cross-sectional melt pool area was varied systematically via process mapping. Increasing melt pool area through the speed function variable was observed to significantly reduce porosity in the part.

  10. Beam loss caused by edge focusing of injection bump magnets and its mitigation in the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

    Science.gov (United States)

    Hotchi, H.; Tani, N.; Watanabe, Y.; Harada, H.; Kato, S.; Okabe, K.; Saha, P. K.; Tamura, F.; Yoshimoto, M.

    2016-01-01

    In the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, transverse injection painting is utilized not only to suppress space-charge induced beam loss in the low energy region but also to mitigate foil scattering beam loss during charge-exchange injection. The space-charge induced beam loss is well minimized by the combination of modest transverse painting and full longitudinal painting. But, for sufficiently mitigating the foil scattering part of beam loss, the transverse painting area has to be further expanded. However, such a wide-ranging transverse painting had not been realized until recently due to beta function beating caused by edge focusing of pulsed injection bump magnets during injection. This beta function beating additionally excites random betatron resonances through a distortion of the lattice superperiodicity, and its resultant deterioration of the betatron motion stability causes significant extra beam loss when expanding the transverse painting area. To solve this issue, we newly installed pulse-type quadrupole correctors to compensate the beta function beating. This paper presents recent experimental results on this correction scheme for suppressing the extra beam loss, while discussing the beam loss and its mitigation mechanisms with the corresponding numerical simulations.

  11. Beam loss caused by edge focusing of injection bump magnets and its mitigation in the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

    Directory of Open Access Journals (Sweden)

    H. Hotchi

    2016-01-01

    Full Text Available In the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, transverse injection painting is utilized not only to suppress space-charge induced beam loss in the low energy region but also to mitigate foil scattering beam loss during charge-exchange injection. The space-charge induced beam loss is well minimized by the combination of modest transverse painting and full longitudinal painting. But, for sufficiently mitigating the foil scattering part of beam loss, the transverse painting area has to be further expanded. However, such a wide-ranging transverse painting had not been realized until recently due to beta function beating caused by edge focusing of pulsed injection bump magnets during injection. This beta function beating additionally excites random betatron resonances through a distortion of the lattice superperiodicity, and its resultant deterioration of the betatron motion stability causes significant extra beam loss when expanding the transverse painting area. To solve this issue, we newly installed pulse-type quadrupole correctors to compensate the beta function beating. This paper presents recent experimental results on this correction scheme for suppressing the extra beam loss, while discussing the beam loss and its mitigation mechanisms with the corresponding numerical simulations.

  12. 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...

  13. 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)

  14. Acoustic communication for Maya Autonomous Underwater Vehicle - performance evaluation of acoustic modem

    Digital Repository Service at National Institute of Oceanography (India)

    Afzulpurkar, S.; Maurya, P.; Navelkar, G.S.; Desa, E.S.; Mascarenhas, A.A.M.Q.; Dabholkar, N.A.; Madhan, R.; Prabhudesai, S.P.

    with good range capability and reasonably high communication bandwidth. An elaborate literature survey indicated that EvoLogics acoustic modem [4] and EvoLogics USBL with communication capability [5] would meet the requirements. Though the primary... requirement is communication, this pair was chosen keeping in mind the future requirements of underwater positioning. These modems are shown in Figure 2a and 2b respectively. Figure 2a. EvoLogics modem Figure 2b. Modem with USBL unit...

  15. Report of the Synchrotron Radiation Vacuum Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Avery, R.T.

    1984-06-01

    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.

  16. Development and characterisation of FPGA modems using forward error correction for FSOC

    Science.gov (United States)

    Mudge, Kerry A.; Grant, Kenneth J.; Clare, Bradley A.; Biggs, Colin L.; Cowley, William G.; Manning, Sean; Lechner, Gottfried

    2016-05-01

    In this paper we report on the performance of a free-space optical communications (FSOC) modem implemented in FPGA, with data rate variable up to 60 Mbps. To combat the effects of atmospheric scintillation, a 7/8 rate low density parity check (LDPC) forward error correction is implemented along with custom bit and frame synchronisation and a variable length interleaver. We report on the systematic performance evaluation of an optical communications link employing the FPGA modems using a laboratory test-bed to simulate the effects of atmospheric turbulence. Log-normal fading is imposed onto the transmitted free-space beam using a custom LabVIEW program and an acoustic-optic modulator. The scintillation index, transmitted optical power and the scintillation bandwidth can all be independently varied allowing testing over a wide range of optical channel conditions. In particular, bit-error-ratio (BER) performance for different interleaver lengths is investigated as a function of the scintillation bandwidth. The laboratory results are compared to field measurements over 1.5km.

  17. Beam emittance control by changing injection painting area in a pulse-to-pulse mode in the 3-GeV rapid cycling synchrotron of Japan Proton Accelerator Research Complex

    Science.gov (United States)

    Saha, P. K.; Harada, H.; Hayashi, N.; Horino, K.; Hotchi, H.; Kinsho, M.; Takayanagi, T.; Tani, N.; Togashi, T.; Ueno, T.; Yamazaki, Y.; Irie, Y.

    2013-12-01

    The 3-GeV rapid cycling synchrotron (RCS) of Japan Proton Accelerator Research Complex (J-PARC) simultaneously delivers high intensity beam to the Material and Life Science Experimental Facility (MLF) as well as to the main ring (MR) at a repetition rate of 25 Hz. The RCS is designed for a beam power of 1 MW. RCS has to meet not only the need of power upgrade but also the specific requirement of each downstream facility. One of the issues, especially for high intensity operation, is to maintain two different transverse sizes of the extracted beam for MLF and MR; namely, a wider beam for MLF in order to reduce damage on the neutron production target but reversely a narrower one for the MR in order to ensure a permissible beam loss in the beam transport line of 3-GeV to MR and also in the MR. We proposed pulse-to-pulse direct control of the transverse painting area during the RCS beam injection process in order to get an extracted beam profile as desired. In addition to two existing dc septum magnets used for fixing injected beam trajectory for MLF beam, two additional dipoles named pulse steering magnets are designed for that purpose in order to control injected beam trajectory for a smaller painting area for the MR. The magnets are already installed in the injection beam transport line and successfully commissioned well in advance before they will be put in normal operation in 2014 for the 400 MeV injected beam energy upgraded from that of the present 181 MeV. Their parameters are found to be consistent to those expected in the corresponding numerical simulations. A trial one cycle user operation run for a painting area of 100πmmmrad for the MR switching from the MLF painting area of 150πmmmrad has also been successfully carried out. The extracted beam profile for the MR is measured to be sufficiently narrower as compared to that for the MLF, consistent with numerical simulation successfully demonstrating validity of the present principle.

  18. Beam emittance control by changing injection painting area in a pulse-to-pulse mode in the 3-GeV rapid cycling synchrotron of Japan Proton Accelerator Research Complex

    Directory of Open Access Journals (Sweden)

    P. K. Saha

    2013-12-01

    Full Text Available The 3-GeV rapid cycling synchrotron (RCS of Japan Proton Accelerator Research Complex (J-PARC simultaneously delivers high intensity beam to the Material and Life Science Experimental Facility (MLF as well as to the main ring (MR at a repetition rate of 25 Hz. The RCS is designed for a beam power of 1 MW. RCS has to meet not only the need of power upgrade but also the specific requirement of each downstream facility. One of the issues, especially for high intensity operation, is to maintain two different transverse sizes of the extracted beam for MLF and MR; namely, a wider beam for MLF in order to reduce damage on the neutron production target but reversely a narrower one for the MR in order to ensure a permissible beam loss in the beam transport line of 3-GeV to MR and also in the MR. We proposed pulse-to-pulse direct control of the transverse painting area during the RCS beam injection process in order to get an extracted beam profile as desired. In addition to two existing dc septum magnets used for fixing injected beam trajectory for MLF beam, two additional dipoles named pulse steering magnets are designed for that purpose in order to control injected beam trajectory for a smaller painting area for the MR. The magnets are already installed in the injection beam transport line and successfully commissioned well in advance before they will be put in normal operation in 2014 for the 400 MeV injected beam energy upgraded from that of the present 181 MeV. Their parameters are found to be consistent to those expected in the corresponding numerical simulations. A trial one cycle user operation run for a painting area of 100π  mm mrad for the MR switching from the MLF painting area of 150π  mm mrad has also been successfully carried out. The extracted beam profile for the MR is measured to be sufficiently narrower as compared to that for the MLF, consistent with numerical simulation successfully demonstrating validity of the

  19. Synchrotron based spallation neutron source concepts

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Y.

    1998-07-01

    During the past 20 years, rapid-cycling synchrotrons (RCS) have been used very productively to generate short-pulse thermal neutron beams for neutron scattering research by materials science communities in Japan (KENS), the UK (ISIS) and the US (IPNS). The most powerful source in existence, ISIS in the UK, delivers a 160-kW proton beam to a neutron-generating target. Several recently proposed facilities require proton beams in the MW range to produce intense short-pulse neutron beams. In some proposals, a linear accelerator provides the beam power and an accumulator ring compresses the pulse length to the required {approx} 1 {micro}s. In others, RCS technology provides the bulk of the beam power and compresses the pulse length. Some synchrotron-based proposals achieve the desired beam power by combining two or more synchrotrons of the same energy, and others propose a combination of lower and higher energy synchrotrons. This paper presents the rationale for using RCS technology, and a discussion of the advantages and disadvantages of synchrotron-based spallation sources.

  20. DC-PLC Modem design for PV module monitoring

    Directory of Open Access Journals (Sweden)

    Seong-Duc Ma

    2016-01-01

    Full Text Available Nowadays, power line communication (PLC is a very efficient technique in cost aspect because it is communication system using power line without extra communication cables. In case of DC-PLC, it send a communication signal of the high frequency band to the monitoring system through the DC power line and is widely used for DC grid or the distributed generation system using DC source. Especially, the management system which evaluates the performance and efficiency of PV module by measuring PV power through monitoring system based on the DC-PLC has been increased. In this paper, apply the DC-PLC method for low cost PV module monitoring system and constitutes a measuring device and communication modem on a MCU. For the communication performance, we use the digital filter and apply the multi-carrier communication. The proposed DC-PLC Modem is verified through simulation and experiment.

  1. Beam-loss induced pressure rise of Large Hadron Collider collimator materials irradiated with 158  GeV/u In^{49+} ions at the CERN Super Proton Synchrotron

    Directory of Open Access Journals (Sweden)

    E. Mahner

    2004-10-01

    Full Text Available During heavy ion operation, large pressure rises, up to a few orders of magnitude, were observed at CERN, GSI, and BNL. The dynamic pressure rises were triggered by lost beam ions that impacted onto the vacuum chamber walls and desorbed about 10^{4} to 10^{7} molecules per ion. The deterioration of the dynamic vacuum conditions can enhance charge-exchange beam losses and can lead to beam instabilities or even to beam abortion triggered by vacuum interlocks. Consequently, a dedicated measurement of heavy-ion induced molecular desorption in the GeV/u energy range is important for Large Hadron Collider (LHC ion operation. In 2003, a desorption experiment was installed at the Super Proton Synchrotron to measure the beam-loss induced pressure rise of potential LHC collimator materials. Samples of bare graphite, sputter coated (Cu, TiZrV graphite, and 316 LN (low carbon with nitrogen stainless steel were irradiated under grazing angle with 158  GeV/u indium ions. After a description of the new experimental setup, the results of the pressure rise measurements are presented, and the derived desorption yields are compared with data from other experiments.

  2. Simulation study on control of spill structure of slow extracted beam from a medical synchrotron with feed-forward and feedback using a fast quadruple magnet and RF-knockout system

    Science.gov (United States)

    Muraoka, Ryo; Nakanishi, Tetsuya

    2017-02-01

    A feedback control of the spill structure for the slow beam extraction from the medical synchrotron using a fast quadruple and radio frequency (RF)-knockout (QAR method) is studied to obtain the designed spill structure. In addition the feed-forward control is used so that the feedback control is performed effectively. In this extraction method, the spill of several ms are extracted continuously with an interval time of less than 1 ms. Beam simulation showed that a flat spill structure was effectively obtained with feed-forward and feedback control system as well as a step-wise structure which is useful for the shortening of an irradiation time in a spot scanning operation. The effect of current ripples from main quadruple magnet's power supplies could be also reduced with the feedback control application.

  3. Modem -repeater for narrow band technology of PLC

    OpenAIRE

    Bednář, Jan

    2014-01-01

    Bakalářská práce je zaměřená na problematiku PLC komunikace, konkrétně na PLC modem. Pro začátek je nutné se seznámit s technologií PLC jako takovu, nastudovat principy přenosu, výhody, nevýhody. V další části se blíže zaměřím na samotný modem a jeho návrh, od výběru vhodné komunikační jednotky podle daných paramtrů, externích obvodů pro úpravu signálu. Nakonec navhrnu plošný spoj, modem realizovat a ověřit si jeho funkčnost. Bachelor’s thesis is focused on PLC communications, particulary ...

  4. Programmable rate modem utilizing digital signal processing techniques

    Science.gov (United States)

    Bunya, George K.; Wallace, Robert L.

    1989-01-01

    The engineering development study to follow was written to address the need for a Programmable Rate Digital Satellite Modem capable of supporting both burst and continuous transmission modes with either binary phase shift keying (BPSK) or quadrature phase shift keying (QPSK) modulation. The preferred implementation technique is an all digital one which utilizes as much digital signal processing (DSP) as possible. Here design tradeoffs in each portion of the modulator and demodulator subsystem are outlined, and viable circuit approaches which are easily repeatable, have low implementation losses and have low production costs are identified. The research involved for this study was divided into nine technical papers, each addressing a significant region of concern in a variable rate modem design. Trivial portions and basic support logic designs surrounding the nine major modem blocks were omitted. In brief, the nine topic areas were: (1) Transmit Data Filtering; (2) Transmit Clock Generation; (3) Carrier Synthesizer; (4) Receive AGC; (5) Receive Data Filtering; (6) RF Oscillator Phase Noise; (7) Receive Carrier Selectivity; (8) Carrier Recovery; and (9) Timing Recovery.

  5. Using CNR to Realize the Cable Modem MAC Authentication%通过CNR实现Cable Modem MAC认证

    Institute of Scientific and Technical Information of China (English)

    赵天元

    2005-01-01

    基于Cable Modem的认证系统的开发一直相对滞后,这也相对制约了Cable Modem高级业务的发展.介绍了笔者对Cable Modem认证的一些新的思路及尝试,通过建立Cable Modem MAC认证弥补现有认证系统的不足.

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

    Energy Technology Data Exchange (ETDEWEB)

    Thomlinson, W.

    1992-10-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Thomlinson, W.

    1992-01-01

    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. Multiharmonic rf feedforward system for compensation of beam loading and periodic transient effects in magnetic-alloy cavities of a proton synchrotron

    Science.gov (United States)

    Tamura, Fumihiko; Ohmori, Chihiro; Yamamoto, Masanobu; Yoshii, Masahito; Schnase, Alexander; Nomura, Masahiro; Toda, Makoto; Shimada, Taihei; Hasegawa, Katsushi; Hara, Keigo

    2013-05-01

    Beam loading compensation is a key for acceleration of a high intensity proton beam in the main ring (MR) of the Japan Proton Accelerator Research Complex (J-PARC). Magnetic alloy loaded rf cavities with a Q value of 22 are used to achieve high accelerating voltages without a tuning bias loop. The cavity is driven by a single harmonic (h=9) rf signal while the cavity frequency response also covers the neighbor harmonics (h=8,10). Therefore the wake voltage induced by the high intensity beam consists of the three harmonics, h=8,9,10. The beam loading of neighbor harmonics is the source of periodic transient effects and a possible source of coupled bunch instabilities. In the article, we analyze the wake voltage induced by the high intensity beam. We employ the rf feedforward method to compensate the beam loading of these three harmonics (h=8,9,10). The full-digital multiharmonic feedforward system was developed for the MR. We describe the system architecture and the commissioning methodology of the feedforward patterns. The commissioning of the feedforward system has been performed by using high intensity beams with 1.0×1014 proteins per pulse. The impedance seen by the beam is successfully reduced and the longitudinal oscillations due to the beam loading are reduced. By the beam loading compensation, stable high power beam operation is achieved. We also report the reduction of the momentum loss during the debunching process for the slow extraction by the feedforward.

  9. Fourier transform infrared spectrochemical imaging: review of design and applications with a focal plane array and multiple beam synchrotron radiation source.

    Science.gov (United States)

    Hirschmugl, Carol J; Gough, Kathleen M

    2012-05-01

    The beamline design, microscope specifications, and initial results from the new mid-infrared beamline (IRENI) are reviewed. Synchrotron-based spectrochemical imaging, as recently implemented at the Synchrotron Radiation Center in Stoughton, Wisconsin, demonstrates the new capability to achieve diffraction limited chemical imaging across the entire mid-infrared region, simultaneously, with high signal-to-noise ratio. IRENI extracts a large swath of radiation (320 hor. × 25 vert. mrads(2)) to homogeneously illuminate a commercial infrared (IR) microscope equipped with an IR focal plane array (FPA) detector. Wide-field images are collected, in contrast to single-pixel imaging from the confocal geometry with raster scanning, commonly used at most synchrotron beamlines. IRENI rapidly generates high quality, high spatial resolution data. The relevant advantages (spatial oversampling, speed, sensitivity, and signal-to-noise ratio) are discussed in detail and demonstrated with examples from a variety of disciplines, including formalin-fixed and flash-frozen tissue samples, live cells, fixed cells, paint cross-sections, polymer fibers, and novel nanomaterials. The impact of Mie scattering corrections on this high quality data is shown, and first results with a grazing angle objective are presented, along with future enhancements and plans for implementation of similar, small-scale instruments.

  10. Modem Handles Data At 160 Mb/s

    Science.gov (United States)

    Budinger, James M.; Miller, Susan P.; Kappes, J. Mark; Layer, David; House, Gilmore

    1993-01-01

    Trellis-coded octal-phase-shift-keying modem transmits and receives continuous or bursted digital data for satellite applications. Helps satisfy increasing demands for communication of high-speed digital data from sources like high-performance computers and high-definition television transmitters, as well as multiplexed signals from slower signal sources. Increases maximum effective bit rate accommodated in standard 72-MHz-wide commercial satellite-transponder radio channel from 120 Mb/s to 160 Mb/s. Principal advantages: spectral efficiency and power efficiency.

  11. Modulation of synchrotron radiation by acoustic oscillations

    CERN Document Server

    Mkrtchyan, A R; Kocharyan, L A; Mirzoyan, V K

    1986-01-01

    By means of a quartz single crystal excited by piezoelectric oscillations, the modulation of synchrotron radiation reflected from the quartz planes (1011) is realized for frequencies ranging from 1 Hz to 15 kHz when the Bragg condition is satisfied. The wavelength of synchrotron radiation ranged from 0.3 to 12A. The patterns of modulated beams taken from oscillograph and analyzer screens are shown.

  12. FINAL TECHNICAL REPORT FOR DE-FG02-05ER64097 Systems and Methods for Injecting Helium Beams into a Synchrotron Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Bush, David A

    2008-09-30

    A research grant was approved to fund development of requirements and concepts for extracting a helium-ion beam at the LLUMC proton accelerator facility, thus enabling the facility to better simulate the deep space environment via beams sufficient to study biological effects of accelerated helium ions in living tissues. A biologically meaningful helium-ion beam will be accomplished by implementing enhancements to increase the accelerator's maximum proton beam energy output from 250MeV to 300MeV. Additional benefits anticipated from the increased energy include the capability to compare possible benefits from helium-beam radiation treatment with proton-beam treatment, and to provide a platform for developing a future proton computed tomography imaging system.

  13. Transversal effects of the space charge in an electrified particle beam (the proton synchrotron Saturne) (1963); Les effets transversaux de la charge d'espace dans les faisceaux de particules electrisees (synchrotron a protons Saturne) (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Faure, J.; Gouttefangeas, M.; Levy-Mandel, R.; Vienet, R.; Lago, B.; Loeb, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    This is a study of the repulsive electrostatic forces existing inside a proton beam focused by the magnetic field of a circular accelerator. The general equation that rules the variation of beam density versus time can be rewritten by a fairly simple reasoning, A numerical method to solve this equation is then developed. The next step is then to find an optimum beam, a gaussian distribution of density being proposed allowing to find an analytical solution to the problem. (authors) [French] On etudie l'action des forces electrostatiques de repulsion qui existent dans un faisceau de protons focalise par le champ magnetique d'un accelerateur circulaire. L'equation generale qui regit la variation de densite du faisceau au cours du temps est retrouvee par un raisonnement simple. On developpe une methode numerique de resolution de cette equation. On pose le probleme de la recherche d'un faisceau optimal et on propose une loi de repartition gaussienne de densite qui permet de trouver une solution analytique au probleme. (auteurs)

  14. Breast tomography with synchrotron radiation

    Science.gov (United States)

    Pani, Silvia; Arfelli, Fulvia; Dreossi, Diego; Montanari, Francesco; Longo, Renata; Olivo, Alessandro; Poropat, Paolo; Zanconati, Fabrizio; Palma, Ludovico D.; Castelli, Edoardo

    2002-05-01

    A feasibility study of breast CT with synchrotron radiation is currently being carried on at Elettra, the Trieste synchrotron radiation facility. Breast CT cannot be implemented easily with conventional radiographic tubes, due to the high dose that would be delivered to the breast by a polychromatic X-ray spectrum. The possibility of tuning the beam energy, available at a synchrotron radiation beamline, allows a significant reduction in the delivered dose, and at the same time the use of monochromatic beams avoids beam hardening artifacts on the reconstructed image. Images of in vitro breast tissue samples have been acquired by means of a high efficiency linear array detector coupled to a VLSI single photon counting readout electronics. The pixel width, determining the pixel size of the reconstructed image, is 200 micrometers , while the pixel height, determining the CT slice thickness, is 300 micrometers . Tomograms have been reconstructed by means of standard filtered backprojection algorithms. Images of normal and pathologic breast tissue samples show a good visibility of glandular structure. The delivered dose was in all cases comparable to the one delivered in clinical planar mammography. Due to the promising results we obtained, in vivo studies are under evaluation.

  15. 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

  16. GNU Radio Signal Processing Models for Dynamic Multi-User Burst Modems

    OpenAIRE

    O'Shea, Timothy J; Karra, Kiran

    2016-01-01

    This paper presents a modern method for implementing burst modems in GNU Radio. Since burst modems are widely used for multi-user channel access and sharing in non-broadcast radio systems, this capability is critical to the development of numerous waveforms in GNU Radio. We focus on making such systems easy to develop and adapt to wide classes of modems and computationally efficient at runtime. We use the GNU Radio Event Stream scheduler to demonstrate concise implementations of burst PSK and...

  17. Spin echo in synchrotrons

    Science.gov (United States)

    Chao, Alexander W.; Courant, Ernest D.

    2007-01-01

    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 Δνspin 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 τ between the two crossings. This approximate picture, however, ignores two spin dynamics effects: an interference-overlap effect and a spin echo effect. This paper is to address these two effects. The interference-overlap effect occurs when Δνspin is too small, or when τ is too short, to complete the smearing process. In this case, the two resonance crossings overlap each other, and the final polarization exhibits constructive or destructive interference patterns depending on the exact value of τ. Typically, the beam’s energy spread is large and this interference-overlap 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 τ 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 τ is very large, and could be a sensitive (albeit challenging) way to experimentally test the intricate spin dynamics in a synchrotron. After giving an analysis

  18. Geometric optimization using Monte Carlo simulations of mini-beams of radiation synchrotron; Optimizacion geometrica mediante simulacion Monte Carlo de minihaces de radiacion sincrotron

    Energy Technology Data Exchange (ETDEWEB)

    Manchado de Sola, F.; Vilches Pacheco, M.; Lallena Rojo, A. M.; Prezado, Y.

    2013-07-01

    Still in testing phase, radiation therapy with mini-beams is presented as a promising form of treatment. The irradiation with beams constituted by a group of parallel strips of radiation and shade (peaks and valleys), each an of the which has a width of the order of microns. We studied using Monte Carlo simulation, the effect of the brain caused by the heartbeat pulsed on the reason of dose peak-valley in cranial radiotherapy with mini-beams, depending on the width of peak and the rate of irradiation. (Author)

  19. Radiation protection at synchrotron radiation facilities.

    Science.gov (United States)

    Liu, J C; Vylet, V

    2001-01-01

    A synchrotron radiation (SR) facility typically consists of an injector, a storage ring, and SR beamlines. The latter two features are unique to SR facilities, when compared to other types of accelerator facilities. The SR facilities have the characteristics of low injection beam power, but high stored beam power. The storage ring is generally above ground with people occupying the experimental floor around a normally thin concrete ring wall. This paper addresses the radiation issues, in particular the shielding design, associated with the storage ring and SR beamlines. Normal and abnormal beam losses for injection and stored beams, as well as typical storage ring operation, are described. Ring shielding design for photons and neutrons from beam losses in the ring is discussed. Radiation safety issues and shielding design for SR beamlines, considering gas bremsstrahlung and synchrotron radiation, are reviewed. Radiation source terms and the methodologies for shielding calculations are presented.

  20. Limitations on plasma acceleration due to synchrotron losses

    CERN Document Server

    Barletta, W A; Bonifacio, R; De Salvo, L

    1999-01-01

    In this letter we consider the effect of synchrotron radiation losses due to the betatron motion of the electron beam in its self-induced magnetic field in a plasma accelerator taking into account the charge neutralization factor. The most favorable case is where the plasma density is smaller than the beam density. The contrary regime is strongly disfavored by the synchrotron radiation loss for beams with characteristics for TeV energies. In both cases we find that upon increasing the plasma density the synchrotron losses kill the acceleration process, so that there are limitations on the maximum allowable plasma density.

  1. Moving Shadows, Moving Sun. Early Modem Sundials Restaging Miracles.

    Science.gov (United States)

    Mersmann, Jasmin

    2015-01-01

    Irrespective of geo- or heliocentric presuppositions, the functioning of sundials is based on the observation of moving shadows or light spots. Even though the cast shadow was often simply used to indicate the time, it could also remind the users of the ephemerality of earthly things or function as an index of planetary movements. This article examines the various ways in which early modem sundials visually interpret the moving shadow or light spot. The instruments address the shadow in inscriptions, integrate it into their design (e.g., in cruciform dials) or even manipulate its course (as in the so-called Horologium Ahaz). Both the crucifix and the Ahaz dials not only refer to astronomical miracles but actually restage them. Even though by means of the horologium it was not possible to explain the Old Testament miracle of the shadow moving backward, adepts were able to recreate it on a terrestrial scale.

  2. VLSI IMPLEMENTATION OF AN ANALOG MULTIPLIER FOR MODEM

    Directory of Open Access Journals (Sweden)

    SRIVIDYA .P,

    2011-02-01

    Full Text Available A modem (modulator-demodulator is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goalis to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Here there is a need to mix the signals of different frequencies or signals of different types, whichemphasizes the use of mixers or multipliers for different RF applications. In this paper, A CMOS analog multiplier, with less number of transistors which can operate at high frequencies with low power and high linearity is proposed. The multiplier works on the basis of parallel connected MOS operation circuit.

  3. Implementasi Modem Akustik OFDM pada TMS320C6416

    Directory of Open Access Journals (Sweden)

    Yuandhika Adhi Widhyatmaka

    2013-09-01

    Full Text Available Desain sistem komunikasi digital menggunakan sinyal akustik untuk aplikasi bawah air adalah bidang yang sangat menantang karena sifat yang sangat kompleks dari saluran bawah air. Teknologi yang dikenal dengan sebutan underwater acoustic merupakan jawaban atas tantangan terhadap keterbatasan kemampuan pengiriman sinyal informasi pada media air. Hal ini disebabkan karena gelombang elektromagnetik dan radio tidak dapat mencapai jarak yang jauh pada medium air karena akan menghasilkan redaman yang sangat besar, sementara sinyal akustik dapat mencapai jarak yang jauh walaupun dengan kecepatan dan bandwidth yang terbatas. Tugas akhir ini bertujuan untuk merancang sistem tersebut, yang secara efektif dapat menahan efek samping saluran namun tetap memberikan laju data yang memadai. Untuk tujuan ini, sebuah studi mendalam tentang saluran komunikasi bawah air dilakukan dandianalisis. Seiring dengan kemajuan yang signifikan telah dibuat penggunaan modulasi multicarrier dalam bentuk ortogonal frekuensi division multiplexing (OFDM dengan data rate tinggi untuk komunikasi akustik bawah air. Dalam tugas akhir ini, implementasi modem akustik OFDM pada sistem single-input single-output menggunakan modul fixed-point DSP TMS320C6416 di mana inti DSP berjalan pada 1 GHz. Terdapat terdapat tiga kategori untuk mengetahui karakteristik modem akustik OFDM yang ditampilkan dalam grafik Bit Error Rate (BER terhadap Signal to Noise Ratio (SNR. Pengujian dilakukan dengan mengirimkan citra 40x64 8bit. Kinerja terbaik terdapat pada implementasi sistem mfile dengan nilai BER mencapai 0,0067 pada 32 subcarrier. Sedangkan kinerja terburuk terdapat pada implementasi sistem pada TMS320C6416 dan sistem simulink rata-rata nilai BER 0,5 dikarenakan kondisi sample rate antar perangkat yang tidak sinkron.

  4. Feasibility study of silicon PN photodiodes as X-ray intensity monitors for high flux X-ray beam with synchrotron radiation

    CERN Document Server

    Sato, K

    1999-01-01

    The basic properties of silicon PN photodiodes as X-ray detectors with synchrotron radiation and their application to XAFS measurements have been investigated. The effects of diffraction peaks due to the crystalline structure of the photodiodes have been eliminated by mounting the scintillators on the photodiodes; (1) CsI(Tl) crystal as a X-ray total absorption detection medium and (2) plastic scintillator as a non-crystalline solid state X-ray detection medium. An accurate comparison between XAFS signals detected by ionization chambers and silicon PN photodiodes is presented. It is shown that good quality XAFS measurements with silicon PN photodiodes are possible by eliminating the diffraction effects with scintillator photodiode configurations.

  5. 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.

  6. Medical applications of synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Fiber structural analysis by synchrotron radiation

    CERN Document Server

    Kojima, J I; Kikutani, T

    2003-01-01

    Topics of fiber structural analysis by synchrotron radiation are explained. There are only three synchrotron radiation facilities in the world, SPring-8 (Super Photon ring-8) in Japan, APS (Advanced Photon Source) in U.S.A. and ESRF (European Synchrotron Radiation Facility) in France. Online measurement of melt spinning process of PET and Nylon6 is explained in detail. Polypropylene and PBO (poly-p-phenylenebenzobisoxazole) was measured by WAXD (Wide Angle X-ray Diffraction)/SAXS (Small Angle X-ray Scattering) at the same time. Some examples of measure of drawing process of fiber are described. The structure formation process of spider's thread was measured. Micro beam of X-ray of synchrotron facility was improved and it attained to 65nm small angle resolving power by 10 mu m beamsize. (S.Y.)

  8. A Proposal to the Department of Energy for The Fabrication of a Very High Energy Polarized Gama Ray Beam Facility and A Program of Medium Energy Physics Research at The National Synchrotron Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Sandorfi, A.M.; LeVine, M.J.; Thorn, C.E.; Giordano, G.; Matone, G.

    1982-09-01

    This proposal requests support for the fabrication and operation of a modest facility that would provide relatively intense beams of monochromatic and polarized photons with energies in the range of several hundreds of MeV. These {gamma} rays would be produced by Compton backscattering laser light from the electrons circulating in the 2.5-3.0 GeV 'X-RAY' storage ring of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The excellent emittance, phase space, and high current of this state-of-the-art storage ring will allow the production of 2 x 10{sup 7} {gamma} rays per second. These photons would be tagged by detecting the scattered electrons, thereby determining the energy to 2.7 MeV for all {gamma}-ray energies. The efficiency of this tagging procedure is 100% and the {gamma}-ray beam would be essentially background free. Tagging will also allow the flexibility of operating with a dynamic range as large as 200 MeV in photon energy while still preserving high resolution and polarization. These beams will permit a fruitful study of important questions in medium-energy nuclear physics. The initial goals of this program are to reach reliable operation with photon energies up to 300 MeV and to develop {gamma}-ray beams with energies up to about 500 MeV. To demonstrate reliable operation, a modest physics program is planned that, for the most part, utilizes existing magnets and detector systems but nonetheless addresses several important outstanding problems. Gamma ray beams of the versatility, intensity, energy, and resolution that can be achieved at this facility are not currently available at any other world facility either existing or under construction. Furthermore, the proposed program would produce the first intense source of medium-energy {gamma} rays that are polarized. Because of the difficulties in producing such polarized beams, it is very unlikely that viable alternate sources can be developed in the near future; at

  9. Synchrotron radiation for direct analysis of metalloproteins on electrophoresis gels.

    Science.gov (United States)

    Ortega, Richard

    2009-03-01

    Metalloproteomics requires analytical techniques able to assess and quantify the inorganic species in metalloproteins. The most widely used methods are hyphenated techniques, based on the coupling of a high resolution chromatographic method with a high sensitivity method for metal analysis in solution. An alternative approach is the use of methods for solid sample analysis, combining metalloprotein separation by gel electrophoresis and direct analysis of the gels. Direct methods are based on beam analysis, such as lasers, ion beams or synchrotron radiation beams. The aim of this review article is to present the main features of synchrotron radiation based methods and their applications for metalloprotein analysis directly on electrophoresis gels. Synchrotron radiation X-ray fluorescence has been successfully employed for sensitive metal identification, and X-ray absorption spectroscopy for metal local structure speciation in proteins. Synchrotron based methods will be compared to ion beam and mass spectrometry for direct analysis of metalloproteins in electrophoresis gels.

  10. Two-dimensional micro-beam imaging of trace elements in a single plankton measured by a synchrotron radiation X-ray fluorescence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ezoe, Masako; Sasaki, Miho; Hokura, Akiko; Nakai, Izumi [Tokyo Univ. of Science, Faculty of Science, Tokyo (Japan); Terada, Yasuko [Japan Synchrotron Radiation Research Inst., Mikazuki, Hyogo (Japan); Yoshinaga, Tatsuki; Tukamoto, Katsumi [Tokyo Univ., Ocean Research Inst., Tokyo (Japan); Hagiwara, Atsushi [Nagasaki Univ., Graduate School of Science and Technology, Bunkyou, Nagasaki (Japan)

    2002-10-01

    Two-dimensional imaging and a quantitative analysis of trace elements in rotifer, Brachionus plicatilis, belonging to zooplankton, were carried out by a synchrotron radiation X-ray fluorescence analysis (SR-XRF). The XRF imaging revealed that female rotifers accumulated Fe and Zn in the digestive organ and Fe, Zn, Cu, and Ca in the sexual organs, while the Mn level was high in the head. From a quantitative analysis by inductively coupled plasma mass spectrometry (ICP-MS), we found that rotifers eat the chlorella and accumulate the above elements in the body. The result of quantitative analyses of Mn, Cu, and Zn by SR-XRF in a single sample is in fair agreement with the average values determined by ICP-MS analyses, which were obtained by measuring a large number of rotifers, digested by nitric acid. The present study has demonstrated that SR-XRF is an effective tool for the trace element analysis of a single individual of rotifer. (author)

  11. Irradiation of intracerebral 9L gliosarcoma by a single array of microplanar x-ray beams from a synchrotron: balance between curing and sparing

    Energy Technology Data Exchange (ETDEWEB)

    Regnard, Pierrick [Biomedical Facility, ESRF, BP220, F 38043 Grenoble (France); Duc, Geraldine Le [Biomedical Facility, ESRF, BP220, F 38043 Grenoble (France); Braeuer-Krisch, Elke [Biomedical Beamline, ESRF, BP220, F 38043 Grenoble (France); Tropres, Irene [MRI Unit, CHU A Michallon, BP217, F 38043 Grenoble (France); Siegbahn, Erik Albert [Biomedical Beamline, ESRF, BP220, F 38043 Grenoble (France); Kusak, Audrey [Biomedical Beamline, ESRF, BP220, F 38043 Grenoble (France); Clair, Charlotte [Biomedical Facility, ESRF, BP220, F 38043 Grenoble (France); Bernard, Helene [Biomedical Facility, ESRF, BP220, F 38043 Grenoble (France); Dallery, Dominique [Biomedical Facility, ESRF, BP220, F 38043 Grenoble (France); Laissue, Jean A [Institute of Pathology, University of Bern, Murtenstrasse 31, Postfach 62, CH-3010 Bern, Switcherland (Switzerland); Bravin, Alberto [Biomedical Beamline, ESRF, BP220, F 38043 Grenoble (France)

    2008-02-21

    The purpose of this work was the understanding of microbeam radiation therapy at the ESRF in order to find the best compromise between curing of tumors and sparing of normal tissues, to obtain a better understanding of survival curves and to report its efficiency. This method uses synchrotron-generated x-ray microbeams. Rats were implanted with 9L gliosarcomas and the tumors were diagnosed by MRI. They were irradiated 14 days after implantation by arrays of 25 {mu}m wide microbeams in unidirectional mode, with a skin entrance dose of 625 Gy. The effect of using 200 or 100 {mu}m center-to-center spacing between the microbeams was compared. The median survival time (post-implantation) was 40 and 67 days at 200 and 100 {mu}m spacing, respectively. However, 72% of rats irradiated at 100 {mu}m spacing showed abnormal clinical signs and weight patterns, whereas only 12% of rats were affected at 200 {mu}m spacing. In parallel, histological lesions of the normal brain were found in the 100 {mu}m series only. Although the increase in lifespan was equal to 273% and 102% for the 100 and 200 {mu}m series, respectively, the 200 {mu}m spacing protocol provides a better sparing of healthy tissue and may prove useful in combination with other radiation modalities or additional drugs.

  12. Airfoil sampling of a pulsed Laval beam with tunable vacuum ultraviolet (VUV) synchrotron ionization quadrupole mass spectrometry: Application to low--temperature kinetics and product detection

    Energy Technology Data Exchange (ETDEWEB)

    Soorkia, Satchin; Liu, Chen-Lin; Savee, John D; Ferrell, Sarah J; Leone, Stephen R; Wilson, Kevin R

    2011-10-12

    A new pulsed Laval nozzle apparatus with vacuum ultraviolet (VUV) synchrotron photoionization quadrupole mass spectrometry is constructed to study low-temperature radicalneutralchemical reactions of importance for modeling the atmosphere of Titan and the outer planets. A design for the sampling geometry of a pulsed Laval nozzle expansion has beendeveloped that operates successfully for the determination of rate coefficients by time-resolved mass spectrometry. The new concept employs airfoil sampling of the collimated expansion withexcellent sampling throughput. Time-resolved profiles of the high Mach number gas flow obtained by photoionization signals show that perturbation of the collimated expansion by theairfoil is negligible. The reaction of C2H with C2H2 is studied at 70 K as a proof-of-principle result for both low-temperature rate coefficient measurements and product identification basedon the photoionization spectrum of the reaction product versus VUV photon energy. This approach can be used to provide new insights into reaction mechanisms occurring at kinetic ratesclose to the collision-determined limit.

  13. Polymer research and synchrotron radiation perspectives

    NARCIS (Netherlands)

    Portale, Giuseppe; Hermida-Merino, Daniel; Bras, Wim

    2016-01-01

    The developments in synchrotron radiation based polymer research have been profound over the last two decades. Not only have many more beamlines suitable for soft condensed matter research become available since the pioneering days but also the technical developments with respect to X-ray beam quali

  14. The Australian synchrotron; Le synchrotron australien

    Energy Technology Data Exchange (ETDEWEB)

    Farhi, R

    2005-06-15

    This document recalls the historical aspects of the Australian Synchrotron which will be implemented in 2007. It presents then the objectives of this program, the specifications of the ring and the light lines. (A.L.B.)

  15. Characterization of modems and error correcting protocols using a scintillation playback system

    Science.gov (United States)

    Rabinovich, William S.; Mahon, Rita; Ferraro, Mike S.; Murphy, James L.; Moore, Christopher I.

    2016-03-01

    The performance of free space optical (FSO) communication systems is strongly affected by optical scintillation. Scintillation fades can cause errors when the power on a detector falls below its noise floor, while surges can overload a detector. The very long time scale of scintillation compared to a typical bit in an FSO link means that error-correcting protocols designed for fiber optic links are inappropriate for FSO links. Comparing the performance effects of different components, such as photodetectors, or protocols, such as forward error correction, in the field is difficult because conditions are constantly changing. On the other hand, laboratory-based turbulence simulators, often using hot plates and fans, do not really simulate the effects of long-range propagation through the atmosphere. We have investigated a different approach. Scintillation has been measured during field tests using FSO terminals by sending a continuous wave beam through the atmosphere. A high dynamic range photodetector was digitized at a 10 KHz rate and files of the intensity variations were saved. Many hours of scintillation data under different environmental conditions and at different sites have been combined into a library of data. A fiber-optic based scintillation playback system was then used in the laboratory to test modems and protocols with the recorded files. This allowed comparisons using the same atmospheric conditions allowing optimization of such parameters as detector dynamic range. It also allowed comparison and optimization of different error correcting protocols.

  16. 同步辐射高分辨率衍射光束线的设计%Beam line design for high-resolution diffraction at synchrotron radiation sources

    Institute of Scientific and Technical Information of China (English)

    U Pietsch; O H Seeck

    2007-01-01

    The general design of a high-resolution diffraction beamline at a third generation X-ray synchrotron radiation source is presented.For this,we introduce the basics of high resolution diffraction and the optical elements necessary to prepare a nearly parallel but intense X-ray beam with well-defined photon energy for high-resolution application.In particular,the function of double-crystal and four-bounced crystal monochromators is explained in terms of X-ray dynamical theory.As an example,we present the layout of the High Resolution Diffraction(HighRes)beamline at the new synchrotron radiation source PETRA Ⅲ in Hamburg(Germany)which will become operational in 2009.By optimizing the optical components.a resolution in q-space will be achieved down to △q=10-5 nm-1with micron beam size and a flux of more than 10 11 cts/s.%介绍了第三代同步辐射高分辨率X射线衍射光束线的总体设计.给出了高分辨率衍射的基本原理并描述了获得确定光子能量的近平行高强度X射线光束线所必需的光学元件.特别是用X射线动力学理论,解释了双晶及四次反射晶体单色器.作为一个实例,介绍了将于2009年开始在德国汉堡运行的一个新的同步辐射源PETRA Ⅲ的高分辨率衍射(HighRes)光束线的设置情况.通过优化光学部件,对微米尺寸光束,q 空间的分辨减小到△q=10-5 nm-1,光通量大于10 11cts/s.

  17. Cable Modems' Transmitted RF: A Study of SNR, Error Rates, Transmit Levels, and Trouble Call Metrics

    Science.gov (United States)

    Tebbetts, Jo A.

    2013-01-01

    Hypotheses were developed and tested to measure the cable modems operational metrics response to a reconfiguration of the cable modems' transmitted RF applied to the CMTS. The purpose of this experiment was to compare two groups on the use of non-federal RF spectrum to determine if configuring the cable modems' transmitted RF from 25.2…

  18. Three-dimensional numerical analysis of convection and conduction cooling of spherical biocrystals with localized heating from synchrotron X-ray beams.

    Science.gov (United States)

    Mhaisekar, Ashutosh; Kazmierczak, Michael J; Banerjee, Rupak

    2005-05-01

    The differential momentum and thermal energy equations for fluid flow and convective heat-transfer around the sample biocrystal, with coupled internal heat conduction, are solved using advanced computational fluid dynamics techniques. Average \\bar{h} as well as local h(theta) values of the convective heat-transfer coefficients are obtained from the fundamental equations. The results of these numerical solutions show the three-dimensional fluid flow field around the sample in conjunction with the detailed internal temperature distribution inside the crystal. The external temperature rise and maximum internal temperature increase are reported for various cases. The effect of the important system parameters, such as gas velocity and properties, crystal size and thermal conductivity and incident beam conditions (intensity and beam size), are all illustrated with comparative examples. For the reference case, an external temperature rise of 7 K and internal temperature increase of 0.5 K are calculated for a 200 microm-diameter cryocooled spherical biocrystal subjected to a 13 keV X-ray beam of 4 x 10(14) photons s(-1) mm(-2) flux density striking half the sample. For all the cases investigated, numerical analysis shows that the controlling thermal resistance is the rate of convective heat-transfer and not internal conduction. Thermal diffusion results in efficient thermal spreading of the deposited energy and this results in almost uniform internal crystal temperatures (DeltaT(internal) approximately 0.5 K), in spite of the non-uniform h(theta) with no more than 1.3 K internal temperature difference for the worst case of localized and focused beam heating. Rather, the major temperature variation occurs between the outer surface of the crystal/loop system and the gas stream, T(s) - T(gas), which itself is only about DeltaT(external) approximately 5-10 K, and depends on the thermal loading imposed by the X-ray beam, the rate of convection and the size of the loop

  19. Parallel digital modem using multirate digital filter banks

    Science.gov (United States)

    Sadr, Ramin; Vaidyanathan, P. P.; Raphaeli, Dan; Hinedi, Sami

    1994-01-01

    A new class of architectures for an all-digital modem is presented in this report. This architecture, referred to as the parallel receiver (PRX), is based on employing multirate digital filter banks (DFB's) to demodulate, track, and detect the received symbol stream. The resulting architecture is derived, and specifications are outlined for designing the DFB for the PRX. The key feature of this approach is a lower processing rate then either the Nyquist rate or the symbol rate, without any degradation in the symbol error rate. Due to the freedom in choosing the processing rate, the designer is able to arbitrarily select and use digital components, independent of the speed of the integrated circuit technology. PRX architecture is particularly suited for high data rate applications, and due to the modular structure of the parallel signal path, expansion to even higher data rates is accommodated with each. Applications of the PRX would include gigabit satellite channels, multiple spacecraft, optical links, interactive cable-TV, telemedicine, code division multiple access (CDMA) communications, and others.

  20. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  1. Status of the booster synchrotron for SPring-8

    Science.gov (United States)

    Suzuki, H.; Yonehara, H.; Aoki, T.; Tani, N.; Kaneda, T.; Ueyama, Y.; Sasaki, Y.; Nagafuchi, T.; Hayashi, S.; Yokomizo, H.

    1995-02-01

    The specification and the layout of the booster synchrotron for SPring-8 were decided. The synchrotron is designed to accelerate electron or positron beams from 1 to 8 GeV with a repetition cycle of 1 Hz. The construction of the synchrotron was started in 1993. First, one bending, one quadrupole, and one sextupole magnet were made and the results of the magnetic field measurement were acquired. Two septum, one bump, and one kicker magnets for the beam extraction have been made, the field measurement and a few improvements have progressed. The high power test of the first rf cavity was finished successfully. The calibration test of the button position monitor with the signal treatment circuits is advanced now. The residual components of the synchrotron are designed and constructed, and the commissioning of the synchrotron will start in 1996. This paper presents the first measurement of each component.

  2. 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.

  3. Carbyne formation by synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kaito, C.; Kimura, Y.; Hanamoto, K.; Sasaki, M.; Kimura, S.; Nakada, T.; Saito, Y.; Koike, C.; Nakayama, Y. E-mail: nakayamy@se.ritsumei.ac.jp

    2001-07-21

    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.

  4. Synchronization of Synchrotrons for bunch-to-bucket Transfers

    CERN Document Server

    Ferrand, Thibault; Damerau, Heiko; CERN. Geneva. ATS Department

    2015-01-01

    To reach high particle energies with synchrotrons, a chain of several accelerators is required, as the ratio of extraction and injection energy is in the range of 10 to 20 per synchrotron. Hence the beam must be transfered from one accelerator to the next one. This document deals with the bunch-to-bucket transfer method to inject particle bunches composing the beam from a source synchrotron to a target synchrotron. After we highlight the theoretical concept of the bunch-to-bucket transfer, we determine physical limitations due to the beam dynamics and the adiabatic aspect of the particle bunches. A summary of the currently performed bunch-to-bucket transfer scenarios between the accelerators at CERN is given and set in relation with the mentioned theoretical concepts.

  5. Broadband Wireline Provider Service: Cable Modem - Other; BBRI_cableOther12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - Other" technology. Broadband availability is...

  6. Broadband Wireline Provider Service: Cable Modem - DOCSIS 3.0; BBRI_cableDOCSIS12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - DOCSIS 3.0" technology. Broadband availability is...

  7. PREFACE: IUMRS-ICA 2008 Symposium, Sessions 'X. Applications of Synchrotron Radiation and Neutron Beam to Soft Matter Science' and 'Y. Frontier of Polymeric Nano-Soft-Materials - Precision Polymer Synthesis, Self-assembling and Their Functionalization'

    Science.gov (United States)

    Takahara, Atsushi; Kawahara, Seiichi

    2009-09-01

    Applications of Synchrotron Radiation and Neutron Beam to Soft Matter Science (Symposium X of IUMRS-ICA2008) Toshiji Kanaya, Kohji Tashiro, Kazuo Sakura Keiji Tanaka, Sono Sasaki, Naoya Torikai, Moonhor Ree, Kookheon Char, Charles C Han, Atsushi Takahara This volume contains peer-reviewed invited and contributed papers that were presented in Symposium X 'Applications of Synchrotron Radiation and Neutron Beam to Soft Matter Science' at the IUMRS International Conference in Asia 2008 (IUMRS-ICA 2008), which was held on 9-13 December 2008, at Nagoya Congress Center, Nagoya, Japan. Structure analyses of soft materials based on synchrotron radiation (SR) and neutron beam have been developed steadily. Small-angle scattering and wide-angle diffraction techniques clarified the higher-order structure as well as time dependence of structure development such as crystallization and microphase-separation. On the other hand, reflectivity, grazing-incidence scattering and diffraction techniques revealed the surface and interface structural features of soft materials. From the viewpoint of strong interests on the development of SR and neutron beam techniques for soft materials, the objective of this symposium is to provide an interdisciplinary forum for the discussion of recent advances in research, development, and applications of SR and neutron beams to soft matter science. In this symposium, 21 oral papers containing 16 invited papers and 14 poster papers from China, India, Korea, Taiwan, and Japan were presented during the three-day symposium. As a result of the review of poster and oral presentations of young scientists by symposium chairs, Dr Kummetha Raghunatha Reddy (Toyota Technological Institute) received the IUMRS-ICA 2008 Young Researcher Award. We are grateful to all invited speakers and many participants for valuable contributions and active discussions. Organizing committee of Symposium (IUMRS-ICA 2008) Professor Toshiji Kanaya (Kyoto University) Professor Kohji

  8. The measurement of stress and phase fraction distributions in pre and post-transition Zircaloy oxides using nano-beam synchrotron X-ray diffraction

    Science.gov (United States)

    Swan, H.; Blackmur, M. S.; Hyde, J. M.; Laferrere, A.; Ortner, S. R.; Styman, P. D.; Staines, C.; Gass, M.; Hulme, H.; Cole-Baker, A.; Frankel, P.

    2016-10-01

    Zircaloy-4 oxide stress profiles and tetragonal:monoclinic oxide phase fraction distributions were studied using nano-beam transmission X-ray diffraction. Continuous stress relief and phase transformation during the first cycle of oxide growth was observed. The in-plane monoclinic stress was shown to relax strongly up to each transition, whereas in-plane tetragonal stress-relief (near the metal-oxide interface) was only observed post transition. The research demonstrates that plasticity in the metal and the development of a band of in-plane cracking both relax the monoclinic in-plane stress. The observations are consistent with a model of transition in which in-plane cracking becomes interlinked prior to transition. These cracks, combined with the development of cracks with a through-thickness component (driven primarily by plasticity in the metal) and/or a porous network of fine cracks (associated with phase transformation), form a percolation path through the oxide layer. The oxidising species can then percolate from the oxide surface to the metal/oxide interface, at which stage transition then ensues.

  9. 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 ...

  10. 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...

  11. Practical application of noise diffusion in U-70 synchrotron

    Science.gov (United States)

    Ivanov, S. V.; Lebedev, O. P.

    2016-12-01

    This paper briefly outlines the physical substantiation and the engineering implementation of technological systems in the U-70 synchrotron based on controllable noise diffusion of the beam. They include two systems of stochastic slow beam extraction (for high and intermediate energy) and the system of longitudinal noise RF gymnastics designated for flattening the bunch distribution over the azimuth.

  12. Remote Synchrotron Light Instrumentation Using Optical Fibers

    Energy Technology Data Exchange (ETDEWEB)

    De Santis, S.; Yin, Y.

    2009-05-04

    By coupling the emitted synchrotron light into an optical fiber, it is possible to transmit the signal at substantial distances from the light port, without the need to use expensive beamlines. This would be especially beneficial in all those cases when the synchrotron is situated in areas not easily access because of their location, or due to high radiation levels. Furthermore, the fiber output can be easily switched, or even shared, between different diagnostic instruments. We present the latest results on the coupling and dispersion measurements performed at the Advanced Light Source in Berkeley. In several cases, coupling synchrotron light into optical fibers can substantially facilitate the use of beam diagnostic instrumentation that measures longitudinal beam properties by detecting synchrotron radiation. It has been discussed in with some detail, how fiberoptics can bring the light at relatively large distances from the accelerator, where a variety of devices can be used to measure beam properties and parameters. Light carried on a fiber can be easily switched between instruments so that each one of them has 100% of the photons available, rather than just a fraction, when simultaneous measurements are not indispensable. From a more general point of view, once synchrotron light is coupled into the fiber, the vast array of techniques and optoelectronic devices, developed by the telecommunication industry becomes available. In this paper we present the results of our experiments at the Advanced Light Source, where we tried to assess the challenges and limitations of the coupling process and determine what level of efficiency one can typically expect to achieve.

  13. Assessing noise sources at synchrotron infrared ports.

    Science.gov (United States)

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

    2012-01-01

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

  14. 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...

  15. Inauguration of Proton Synchrotron

    CERN Multimedia

    1960-01-01

    On 5 February 1960, the Proton Synchrotron (PS) was formally inaugurated. The great Danish physicist, Niels Bohr, releases a bottle of champagne against a shielding block to launch the PS on its voyage in physics.

  16. Coherent synchrotron radiation: Theory and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Courtland L. Bohn

    2002-07-19

    Our understanding of the generation of coherent synchrotron radiation in magnetic bending systems and its impact on beam dynamics has grown considerably over the past few years. The search for understanding has brought a number of surprises, all related to the complexity of the fully self-consistent problem. Herein I survey the associated phenomenology, theory, and experiments while emphasizing important subtleties that have recently been uncovered. I conclude by speculating on courses of future investigations that may prove fruitful.

  17. Study of complex molecules of biological interest with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Prince, K.C. [Elettra-Sincrotrone Trieste, Strada Statale 14–km 163,5 in AREA Science Park, I-34149 Trieste (Italy); Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, in Area Science Park, I-34149 Trieste (Italy); Molecular Model Discovery Laboratory, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Melbourne, Victoria, 3122 (Australia); Bolognesi, P., E-mail: paola.bolognesi@cnr.it [CNR-ISM, Area della Ricerca di Roma 1, Via Salaria Km. 29,300, Monterotondo (Roma) (Italy); Feyer, V. [Elettra-Sincrotrone Trieste, Strada Statale 14–km 163,5 in AREA Science Park, I-34149 Trieste (Italy); Research Center Jülich, Peter Grünberg Institute (PGI-6), 52425 Jülich (Germany); Plekan, O. [Elettra-Sincrotrone Trieste, Strada Statale 14–km 163,5 in AREA Science Park, I-34149 Trieste (Italy); Avaldi, L. [CNR-ISM, Area della Ricerca di Roma 1, Via Salaria Km. 29,300, Monterotondo (Roma) (Italy)

    2015-10-15

    Synchrotron radiation and synchrotron based spectroscopic techniques have found important applications in the study of isolated molecular species of biological interest. In this paper, some examples of spectroscopic and dynamic studies of amino acids and small peptides, nucleobases and pharmaceuticals are reviewed. Opportunities offered by the advent of new radiation sources combined with novel methods for the production of beams of these molecules are also discussed.

  18. 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)

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

    Science.gov (United States)

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

    2004-01-01

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

  20. 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.

  1. Optical systems for synchrotron radiation. Lecture 2. Mirror systems

    Energy Technology Data Exchange (ETDEWEB)

    Howells, M.R.

    1986-02-01

    The process of reflection of VUV and x-radiation is summarized. The functions of mirrors in synchrotron beamlines are described, which include deflection, filtration, power absorption, formation of a real image, focusing, and collimation. Fabrication of optical surfaces for synchrotron radiation beamlines are described, and include polishing of a near spherical surface as well as bending a cylindrical surface to toroidal shape. The imperfections present in mirrors, aberrations and surface figure inaccuracy, are discussed. Calculation of the thermal load of a mirror in a synchrotron radiation beam and the cooling of the mirror are covered briefly. 50 refs., 7 figs. (LEW)

  2. Proceedings of the workshop on LAMPF II synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.K. (comp.)

    1983-01-01

    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. (GHT)

  3. 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.

  4. Technology of SDH remote maintenance based on telephone MODEM%于基电话网 MODEM 的SDH 远程维护技术

    Institute of Scientific and Technical Information of China (English)

    周伟; 程红霞

    2014-01-01

    This article presents a remote maintenance technology of SDH network in unmanned area based on fixed telephone network and MODEM. It also introduces the application of SDH network remote maintenance based on embedded MODEM and Point-to-Point protocol in detail.%将固定电话网络(PSTN)与调制解调技术(MODEM)相结合,提出了一种解决偏远无人值守地区SDH网络的远程维护技术,详细介绍了基于嵌入式MODEM技术、点对点传输技术(PPP)实现SDH网络远程维护的设计方案。

  5. Two-Way Radio Modem Data Transfer for Newborn Hearing Screening Devices.

    Science.gov (United States)

    Matulat, Peter; Lepper, Ingo; Böttcher, Peter; Parfitt, Ross; Oswald, Hans; Am Zehnhoff-Dinnesen, Antoinette; Deuster, Dirk

    2017-01-01

    The success of a newborn hearing screening program depends on successful tracking and follow-up to ensure that children who have had positive screening results in the first few days of life receive appropriate and timely diagnostic and intervention services. The easy availability, through a suitable infrastructure, of the data necessary for the tracking, diagnosis, and care of children concerned is a major key to enhancing the quality and efficiency of newborn hearing screening programs. Two systems for the automated two-way transmission of newborn hearing screening and configuration data, based on mobile communication technology, for the screening devices MADSEN AccuScreen(®) and Natus Echo-Screen(®) were developed and tested in a field study. Radio modem connections were compared with conventional analogue modem transmissions from Natus Echo-Screen devices for duration, transmission rate, number of lost connections, and frequency of use. The average session duration was significantly lower with the MADSEN AccuScreen (12 s) and Natus Echo-Screen both with radio modem (15 s) than the Natus Echo-Screen with analogue modem (108 s). The transmission rate was significantly higher (898 and 1,758 vs. 181 bytes/s) for the devices with radio modems. Both radio modem devices had significantly lower rates of broken connections after initial connection (2.1 and 0.9 vs. 5.5%). An increase in the frequency of data transmission from the clinics with mobile radio devices was found. The use of mobile communication technology in newborn hearing screening devices offers improvements in the average session duration, transmission rate, and reliability of the connection over analogue solutions. We observed a behavioral change in clinical staff using the new technology: the data exchange with the tracking center is more often used. The requirements for on-site support were reduced. These savings outweigh the small increase in costs for the Internet service provider.

  6. Coherent Synchrotron Radiation: Theory and Simulations.

    Energy Technology Data Exchange (ETDEWEB)

    Novokhatski, Alexander; /SLAC

    2012-03-29

    The physics of coherent synchrotron radiation (CSR) emitted by ultra-relativistic electron bunches, known since the last century, has become increasingly important with the development of high peak current free electron lasers and shorter bunch lengths in storage rings. Coherent radiation can be described as a low frequency part of the familiar synchrotron radiation in bending magnets. As this part is independent of the electron energy, the fields of different electrons of a short bunch can be in phase and the total power of the radiation will be quadratic with the number of electrons. Naturally the frequency spectrum of the longitudinal electron distribution in a bunch is of the same importance as the overall electron bunch length. The interest in the utilization of high power radiation from the terahertz and far infrared region in the field of chemical, physical and biological processes has led synchrotron radiation facilities to pay more attention to the production of coherent radiation. Several laboratories have proposed the construction of a facility wholly dedicated to terahertz production using the coherent radiation in bending magnets initiated by the longitudinal instabilities in the ring. Existing synchrotron radiation facilities also consider such a possibility among their future plans. There is a beautiful introduction to CSR in the 'ICFA Beam Dynamics Newsletter' N 35 (Editor C. Biscari). In this paper we recall the basic properties of CSR from the theory and what new effects, we can get from the precise simulations of the coherent radiation using numerical solutions of Maxwell's equations. In particular, transverse variation of the particle energy loss in a bunch, discovered in these simulations, explains the slice emittance growth in bending magnets of the bunch compressors and transverse de-coherence in undulators. CSR may play same the role as the effect of quantum fluctuations of synchrotron radiation in damping rings. It can limit

  7. 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...

  8. Spatial Coherence of Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Marchesini, S; Coisson, R

    2003-10-30

    Synchrotron Radiation (SR) has been widely used since the 80's as a tool for many applications of UV, soft X rays and hard X rays in condensed matter physics, chemistry and biology. The evolution of SR sources towards higher brightness has led to the design of low-emittance electron storage rings (emittance is the product of beam size and divergence), and the development of special source magnetic structures, as undulators. This means that more and more photons are available on a narrow bandwidth and on a small collimated beam; in other words there is the possibility of getting a high power in a coherent beam. In most applications, a monochromator is used, and the temporal coherence of the light is given by the monochromator bandwidth. With smaller and smaller sources, even without the use of collimators, the spatial coherence of the light has become appreciable, first in the UV and soft X ray range, and then also with hard X rays. This has made possible new or improved experiments in interferometry, microscopy, holography, correlation spectroscopy, etc. In view of these recent possibilities and applications, it is useful to review some basic concepts about spatial coherence of SR, and its measurement and applications. In particular we show how the spatial coherence properties of the radiation in the far field can be calculated with simple operations from the single-electron amplitude and the electron beam angular and position spreads. The gaussian approximation will be studied in detail for a discussion of the properties of the far field mutual coherence and the estimate of the coherence widths, and the comparison with the VanCittert-Zernike limit.

  9. 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.

  10. Compact synchrotron light sources

    CERN Document Server

    Weihreter, Ernst

    1996-01-01

    This book covers a new niche in circular accelerator design, motivated by the promising industrial prospects of recent micromanufacturing methods - X-ray lithography, synchrotron radiation-based micromachining and microanalysis techniques. It describes the basic concepts and the essential challenges for the development of compact synchrotron radiation sources from an accelerator designer's point of view and gives an outline of the actual state of the art. The volume is intended as an introduction and as a reference for physicists, engineers and managers involved in this rapidly developing fiel

  11. Observation of wide rf induced synchrotron sideband depolarizing resonances.

    Science.gov (United States)

    Bychkov, M. A.; Anferov, V. A.; Blinov, B. B.; Courant, E. D.; Crandell, D. A.; Derbenev, Ya. S.; Kaufman, W. A.; Krisch, A. D.; Lorenzon, W.; Nurushev, T. S.; Phelps, R. A.; Wong, V. K.; Caussyn, D. D.; Chu, C. M.; Ellison, T. J. P.; Lee, S. Y.; Rinckel, T.; Schwandt, P.; Sperisen, F.; Stephenson, E. J.; von Przewoski, B.; Ohmori, C.; Minty, M. G.; Russell, A. D.

    1997-04-01

    In a recent experiment with a stored 104.1 MeV vertically polarized proton beam at the IUCF Cooler Ring, we depolarized the beam using an rf solenoid with a magnetic field of about 1.3\\cdot10-3T\\cdotm. We observed the two expected rf depolarizing resonances centered around the protons' 1.5 MHz circulation frequency as in previous experiments. Near each of these resonances, we also found synchrotron sidebands which are caused by the proton's energy oscillations. The strengths and widths of the synchrotron resonances were quite different for the sidebands above and below the circulation frequency.

  12. Successful Beam-Beam Tuneshift Compensation

    Energy Technology Data Exchange (ETDEWEB)

    Bishofberger, Kip Aaron [Univ. of California, Los Angeles, CA (United States)

    2005-01-01

    The performance of synchrotron colliders has been limited by the beam-beam limit, a maximum tuneshift that colliding bunches could sustain. Due to bunch-to-bunch tune variation and intra-bunch tune spread, larger tuneshifts produce severe emittance growth. Breaking through this constraint has been viewed as impossible for several decades. This dissertation introduces the physics of ultra-relativistic synchrotrons and low-energy electron beams, with emphasis placed on the limits of the Tevatron and the needs of a tuneshift-compensation device. A detailed analysis of the Tevatron Electron Lens (TEL) is given, comparing theoretical models to experimental data whenever possible. Finally, results of Tevatron operations with inclusion of the TEL are presented and analyzed. It is shown that the TEL provides a way to shatter the previously inescapable beam-beam limit.

  13. A New Signal Processing Technique of π/4-DQPSK Modem Based on Software Radio

    Institute of Scientific and Technical Information of China (English)

    常疆; 张乃通

    2003-01-01

    π/4-DQPSK modem has been chosen as the modem scheme in many mobile communication systems. A new signal processing technique of π/4-DQPSK modem based on software radio is discussed in this paper. Unlike many other software radio solutions to the subject, we choose a universal digital radio baseband processor operating as the co-processor of DSP. Only the core algorithms for signal processing are implemented with DSP. Thus the computation burden on DSP is reduced significantly. Compared with the traditional ones, the technique mentioned in this paper is more promising and attractive. It is extremely compact and power-efficient, which is often required by a mobile communication system. The implementation of baseband signal processing for π/4-DQPSK modem on this platform is illustrated in detail. Special emphases are laid on the architecture of the system and the algorithms used in the baseband signal processing. Finally, some experimental results are presented and the performances of the signal processing and compensation algorithms are evaluated through computer simulations.

  14. Software-defined open-architecture modems: Historical review and the NILUS approach

    NARCIS (Netherlands)

    Dol, H.S.; Casari, P.; Zwan, T. van der

    2014-01-01

    Flexible/adaptive modems that are reprogramma-ble/reconfigurable at all layers of the communication stack, either by a user or by means of autonomous decisions, are considered as an important enabler for interoperability and cognitive networking in the underwater domain. This paper reviews existing

  15. 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.)

  16. Transfiguration of extracting mirror in synchrotron radiation system at SSRF

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The first extracting mirror is very important for synchrotron radiation monitor (SRM). The SRM system of SSRF (Shanghai Synchrotron Radiation Facility) should extract the visible light with low optical distortion. The analysis of SR power spectrum and heat transfiguration based on Matlab is introduced in this paper, which will be used in calibration. One beryllium mirror with water-cooling is used to transmit X-ray and reflect visible light to satisfy the measurement request. The existing system suffers from a dynamic problem in some beam physics study. The system includes optics, image acquisition and interferometers. One of the instruments is a digital camera providing the image of the beam transverse profile. The hardware configuration will be summarized. The synchrotron radiation measurement system has been in operation in SSRF for more than one year.

  17. The design study for a 500 MeV proton synchrotron with CSNS linac as an injector

    CERN Document Server

    Huang, Liang-Sheng; Ji, Hong-Fei

    2016-01-01

    Using the China Spallation Neutron Source (CSNS) linac as the injector, a 500 MeV proton synchrotron is proposed for multidisciplinary application, such as biology, material and proton therapy. The synchrotron will deliver proton beam with energy from 80 MeV to 500 MeV. A compact lattice design was worked out, and all the important beam dynamics issues were investigated. The 80 MeV H- beam is stripped and injected into the synchrotron by using multi-turn injection. In order to continuously extraction the proton with small beam loss, the achromatic structure is proposed and slow extraction method with RF knock-out is adopted and optimized.

  18. Local transverse coupling impedance measurements in a synchrotron light source from turn-by-turn acquisitions

    National Research Council Canada - National Science Library

    Carlà, Michele; Benedetti, Gabriele; Günzel, Thomas; Iriso, Ubaldo; Martí, Zeus

    2016-01-01

    .... Beam position monitor turn-by-turn analysis for impedance characterization has been usually employed in large circumference machines, while synchrotron light sources have mainly used slow orbit based techniques...

  19. 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.

  20. Polarization factor measurements of flat crystals using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Wohrer, K.; Touati, A.; Chetioui, A.; Rozet, J.P.; Chevallier, P.; Wang, J.X.; Bouisset, P.

    1989-01-01

    A method for measuring polarization factors of flat crystals, using a highly polarized beam source provided by synchrotron radiation, is presented. Application to the test of a graphite mosaic crystal, performed at the LURE-DCI facility in Orsay (France), is reported. Results concerning polarization factors at different energies are discussed in connection with measured crystal reflectivities.

  1. Monochromator on a synchrotron undulator source for liquid surface studies

    DEFF Research Database (Denmark)

    Als-Nielsen, Jens Aage; Freund, A.K.

    1992-01-01

    a monochromator made of a beryllium mosaic crystal using the (002) reflection in Laue geometry placed in undulator beams of DORIS III at the Hamburger Synchrotronstrahlungslabor and of the European Synchrotron Radiation Facility. An analysis of the diffraction properties in terms of mosaic spread, heat load...

  2. Low-Power Direct-Sequence Spread-Spectrum Modem Architecture for Distributed Wireless Sensor Networks

    Energy Technology Data Exchange (ETDEWEB)

    Chien, C; Elgorriaga, I; McConaghy, C

    2001-07-03

    Emerging CMOS and MEMS technologies enable the implementation of a large number of wireless distributed microsensors that can be easily and rapidly deployed to form highly redundant, self-configuring, and ad hoc sensor networks. To facilitate ease of deployment, these sensors should operate on battery for extended periods of time. A particular challenge in maintaining extended battery lifetime lies in achieving communications with low power. This paper presents a direct-sequence spread-spectrum modem architecture that provides robust communications for wireless sensor networks while dissipating very low power. The modem architecture has been verified in an FPGA implementation that dissipates only 33 mW for both transmission and reception. The implementation can be easily mapped to an ASIC technology, with an estimated power performance of less than 1 mW.

  3. Hardware implementation of pi/4-DQPSK modem for mobile communication (Short Communication

    Directory of Open Access Journals (Sweden)

    K.P.M. Bhat

    2001-07-01

    Full Text Available Spectrally efficient digital modulation schemes for land mobile voice transmission applications highlighting advantages of a 7Pi/4-DQPSK modem are briefly reviewed, A procedure to generate 7Pi/4-DQPSK signal by directly mapping pairs of input bits through dibit transformation function and analog multiplexer is described. Details of modulator hardware for a standard data rate of 48 kbps are also incorporated, A promising all-digital receiver structure which lends itself for miniaturisation, is described.

  4. KOMUNIKASI MODEM SERIAL DENGAN MENGGUNAKAN POINT TO POINT PROTOCOL PADA SISTEM OPERASI LINUX

    Directory of Open Access Journals (Sweden)

    Silvia Rostianingsih

    2002-01-01

    Full Text Available Linux Operating System which growing rapidly this day start to attract many people, especially academic and proffesionals in computer's world. Many things which make Linux more attractive is the open source's characterictic, which mean its application is freely available to everyone. In fact, we can get the source code easily, and the stabilize as an operating system getting admission by many society. Linux also can make a connection between modem, even internet. Linux also support the client-server system. Therefore, Local Area Network system can use only one modem as the connection for many computers to go through the internet. Point to point protocol is one of the protocols which used to do the connection to the internet or LAN, because of a lot of things its provided easily, especially the installation and the used of it. Abstract in Bahasa Indonesia : Sistem operasi Linux yang berkembang dengan pesat akhir-akhir ini mulai menarik minat sebagian orang, terutama kalangan akademisi dan profesional yang berkecimpung di dunia komputer. Beberapa hal yang membuat Linux semakin diminati adalah sifat Linux yang open source, artinya banyak aplikasi bersifat gratis, tidak diharuskan untuk membayar. Bahkan source codenya bisa didapatkan dengan mudah, serta kestabilan Linux sebagai sistem operasi mulai diakui oleh banyak kalangan. Sistem operasi Linux juga dapat melakukan hubungan antar modem, bahkan dapat melakukan koneksi ke Internet. Sistem operasi Linux juga mendukung sistem client-server. Jadi di dalam suatu sistem Local Area Network dapat menggunakan hanya dengan satu modem saja untuk dapat koneksi ke Internet dengan menggunakan banyak komputer. Point to Point Protocol merupakan salah satu protocol yang banyak sekali dipakai untuk melakukan koneksi ke Internet maupun ke LAN, karena beberapa kemudahan yang dimiliki, terutama proses instalasi dan penggunaannya. Kata kunci: point to point protocol, linuc, client-server.

  5. Integration of an Acoustic Modem onto a Wave Glider Unmanned Surface Vehicle

    Science.gov (United States)

    2012-06-01

    equation for the power of each wave. (4.9) 2 2 2 [W] 32wave g H T Vρ π Π = The vehicle is of course not able to use all of this power for thrust as...modem and the node. The glider portion of the vehicle tends to lead the float portion by 0.55 meters [6]. Using simple trigonometry we can

  6. 50 GeV proton synchrotron for JAERI/KEK Joint project

    CERN Document Server

    Mori, Y

    2001-01-01

    This paper describes a design of a 50 GeV proton synchrotron for a JAERI-KEK Joint (JKJ) project which has been proposed by High Energy Research Organization (KEK) and Japan Atomic Energy Research Institute (JAERI). The site of the proposed accelerators is JAERI Tokai site. The JKJ project includes particle physics, nuclear physics, material science, life science and nuclear technology, using a new proton accelerator complex. The high beam power allows the production of a variety of intense secondary beams. The accelerator complex consists of the linac, 3 GeV synchrotron and 50 GeV synchrotron. The 3 GeV synchrotron is a rapid cycling synchrotron with the repetition rate of 25 Hz and provides a 1 MW beam for the spallation neutron source and muon facility. At the 50 GeV synchrotron, nuclear and particle physics experiments using anti- protons, kaons, hyperons and primary proton beam are planned. The long-baseline neutrino oscillation from JKJ to Super Kamiokande is also planned. The 50 GeV synchrotron will pr...

  7. Synchrotrons for Hadrontherapy

    Science.gov (United States)

    Pullia, Marco G.

    Since 1990, when the world's first hospital-based proton therapy center opened in Loma Linda, California, interest in dedicated proton and carbon ion therapy facilities has been growing steadily. Today, many proton therapy centers are in operation, but the number of centers offering carbon ion therapy is still very low. This difference reflects the fact that protons are well accepted by the medical community, whereas radiotherapy with carbon ions is still experimental. Furthermore, accelerators for carbon ions are larger, more complicated and more expensive than those for protons only. This article describes the accelerator performance required for hadrontherapy and how this is realized, with particular emphasis on carbon ion synchrotrons.

  8. 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.

  9. Status of the delta synchrotron light-monitoring-system

    CERN Document Server

    Berges, U

    2000-01-01

    A synchrotron radiation source like DELTA needs an optical monitoring system to measure the beam size at different points of the ring with high resolution and accuracy. The measurements with the present synchrotron light monitors show that beam sizes larger than 250 μm can be measured. The measured emittance is of the order of the theoretical values of the optics and goes down to 8 nm rad. The magnification of the system can simply be increased by adding another lens to measure smaller emittances and beamsizes down to 100 μm. In this case you still have an optical image of the beam available, but sometimes the position of the camera has to be adapted due to the great magnification of the optical system. The image processing system which is based on a VME Framegrabber makes a two dimensional gaussian fit to the images from different synchrotron light-monitors. First tests with monochromatic components of the synchrotron radiation (500 nm and 550 nm) and with short time cameras (shutter time...

  10. 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".

  11. Design of a compact synchrotron for medical applications

    CERN Document Server

    Harbi, N A

    2003-01-01

    An optimal design of a low energy (300 MeV) proton synchrotron for medical applications is addressed. The machine has the following properties: (1) The transition energy is higher than the targets final proton beam energy of 300 MeV; (2) the betatron tunes are chosen such that the machine is free of systematic resonances; (3) the machine can accommodate both slow and fast extraction systems; and (4) the machine can provide rapid cycling operations depending on the rf cavity voltage. Applications of this low energy synchrotron are discussed. (10 refs).

  12. Combustion study with synchrotron radiation single photon ionization technique

    Institute of Scientific and Technical Information of China (English)

    YANG Rui; WANG Jing; HUANG Chaoqun; YANG Bin; WEI Lixia; SHAN Xiaobin; SHENG Liusi; ZHANG Yunwu; QI Fei

    2005-01-01

    Here we report a combustion endstation at National Synchrotron Radiation Laboratory (NSRL) and some primary experimental results. Synchrotron radiation can provide the tunable vacuum ultraviolet (VUV) photon with the high intensity and the good collimation. VUV photoionization is a single-photon ionization process. Combined with molecular-beam mass spectrometry (MBMS), the VUV single-photon ionization can be applied to detect the combustion products, especially the intermediates and free radicals produced from combustion process. This method is proved to be a powerful tool for combustion study, which could be helpful for developing combustion kinetic models and understanding the mechanism of combustion reactions.

  13. Space Charge Effects and Limitations in the CERN Proton Synchrotron

    CERN Document Server

    Wasef, R; Damerau, H; Gilardoni, S; Hancock, S; Hernalsteens, C; Huschauer, A; Schmidt, F; Franchetti, G

    2013-01-01

    Space charge produces a large incoherent tune-spread which, in presence of betatronic resonances, could lead to beam losses and emittance growth. In the CERN Proton Synchrotron, at the current injection kinetic energy (1.4 GeV) and even at the future kinetic energy (2 GeV), space charge is one of the main limitations for high brightness beams and especially for the future High- Luminosity LHC beams. Several detailed studies and measurements have been carried out to improve the understanding of space charge limitations to determine the maximum acceptable tune spread and identify the most important resonances causing losses and emittance growth.

  14. Beam cavity interaction

    CERN Document Server

    Gamp, A

    2011-01-01

    We begin by giving a description of the rf generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, rf feedback, and feed-forward are described. Examples of digital rf phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  15. Application of FLUKA to simulate the beam loss monitoring system for the booster of the Shanghai synchrotron radiation facility%FLUKA在上海光源增强器束流损失监测系统模拟中的应用

    Institute of Scientific and Technical Information of China (English)

    任丽; 邱睿; 曾鸣; 李君利; 邵贝贝

    2011-01-01

    上海光源(SSRF)是中国迄今为止最大的大科学装置,在科学界和工业界有着广泛的应用价值。上海光源增强器的束流损失监测系统,对于保障中国首台增强器的正常运行和机器研究都起到重要的作用。针对该束流损失监测系统设计中相关的问题,利用FLUKA程序,对不同能量的束损电子在真空室壁中的簇射过程进行了模拟,并比较了次级粒子在探测器内的能量沉积。结果表明:探测器中对能量沉积起主导作用的是簇射电子,设计方案是可行的。同时讨论了在不同能量束流电子损失下,探测器测量结果的一致性问题。%The Shanghai Synchrotron Radiation Facility is by far the largest scientific facility in China,with wide applications in the scientific community and industry.The beam loss monitoring(BLM) system of the Shanghai Synchrotron Radiation Facility booster plays an important role in protecting normal operation of the first booster in China.Problems in the BLM system design were analyzed using the FLUKA code to simulate the beam electron shower with different kinetic energies in the vacuum chamber wall.The energy deposition of the secondary particles in the detector was compared to show that the shower electrons deposit the most energy in the detector,which can firms the design feasibility.The beam loss measurements for beam with different kinetic energies were also analyzed.

  16. Exacerbation of demyelinating syndrome after exposure to wireless modem with public hotspot.

    Science.gov (United States)

    Johansson, Olle; Redmayne, Mary

    2016-01-01

    In August 2003, 48-year-old JS of Colorado, USA, a fitness therapist and sports nutritionist, contracted neuroinvasive West Nile virus which left her with disabilities due to spinal axonal damage.In August 2014, she suddenly developed symptoms very much like her acute West Nile infection 11 years ago, including focal seizures, ataxia, vertigo and headaches. Her blood count looked normal so there was no obvious infection. What struck her as odd was that when she left her apartment for any length of time, the symptoms stopped. She found out that a new type of wireless modem, enabled for both personal use and functioning as a public hotspot designed to reach up to 100 m, had been installed in the flat under hers.Her neighbor replaced the modem with a router without the hotspot feature. After that, the seizures stopped immediately, and the other symptoms faded gradually, after which she was fine and again could sleep well. Later, when another activated hotspot was installed in an adjacent flat, JS once again noticed symptoms.A possible association between electrohypersensitivity, myelin integrity and exposure to low-intensity radiofrequency electromagnetic fields (RF-EMF) typical in the modern world has recently been proposed. Since the West Nile virus attacks both the nerve cells and the glial ones, one explanation to the above observed case effects is that the initial virus attack and the wireless modem's RF-EMF affect the nervous system through the very same, or similar, avenues, and maybe both via the oligodendrocytes.

  17. Hardware Implementation of a 16-QAM Modem Using Waveform Switching Technique

    Directory of Open Access Journals (Sweden)

    K.P.M. Bhat

    2006-11-01

    Full Text Available A new modem circuit technique is proposed for multilevel signal transmission to utilisethe transmission bandwidth efficiently in bandwidth-constrained voice-band channels. Usingthis technique, a 16-level quadrature amplitude modulated (16-QAM signal is generated as acascaded configuration of an 8-level phase-shift keying (8-PSK and a 4-level amplitude-shiftkeying ( 4-ASK using waveform mapping rules. The data detection procedure, which is basedon the determination of each symbol one-by-one by inspection of their amplitude level andabsolute phase information, is described.

  18. 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

  19. A dedicated infrared synchrotron ring at the ALS

    Science.gov (United States)

    Barry, W.; Biocca, A.; Byrd, J. M.; Byrne, W.; Kwiatkowski, S.; Martin, Michael C.; McKinney, Wayne R.; Nishimura, H.; Sannibale, F.; Steier, C.; Rex, K.; Robin, D.; Stover, G.; Thur, W.; Wu, Y.

    2002-03-01

    We present preliminary plans for a storage ring dedicated to and optimized for the production of synchrotron radiation over the infrared wavelength range from 1 micron to > 1 mm. The site for the 66 m circumference ring is atop the existing ALS booster synchrotron shielding. This area provides enough floor space for both the ring and beamlines, and hutches. We plan to operate the ring in two modes: as a conventional light source and as a superradiant source in the far-IR. In the conventional mode, our design allows greater transmission of light in the far-infrared than typical light sources, and significantly improves beam stability. In the superradiant mode, we hope to achieve very intense coherent emission of synchrotron radiation over the 0.2 - 10 mm wavelength range by shortening the electron bunches. This mode will generate much higher flux & brightness than conventional far-IR and coherent THz sources.

  20. 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.

  1. Geometry optimization using Monte Carlo simulation mini-beams of synchrotron radiation for therapeutic use; Optimizacion geometrica mediante simulacion Monte Carlo de Minihaces de radiacion sincrotron para uso terapeutico

    Energy Technology Data Exchange (ETDEWEB)

    Manchado, F.; Vilches, M.; Guiraldo, D.; Lallena, A. M.

    2011-07-01

    In this paper we have studied, using Monte Carlo simulation, the properties of such beams, degradation with depth traversed, the influence of target motion during irradiation, how to reduce the absorbed dose between bands and how to reduce simulation times.

  2. Longitudinal tracking studies for a high intensity proton synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Lessner, E.; Cho, Y.; Harkay, K.; Symon, K. [Argonne National Laboratory, 9700 Cass Ave., Argonne, Illinois 60439 (United States)

    1996-06-01

    Results from longitudinal tracking studies for a high intensity proton synchrotron designed for a 1-MW spallation source are presented. The machine delivers a proton beam of 0.5 mA time-averaged current at a repetition rate of 30 Hz. The accelerator is designed to have radiation levels that allow hands-on-maintenance. However, the high beam intensity causes strong space charge fields whose effects may lead to particle loss and longitudinal instabilities. The space charge fields modify the particle distribution, distort the stable bucket area and reduce the rf linear restoring force. Tracking simulations were conducted to analyze the space charge effects on the dynamics of the injection and acceleration processes and means to circumvent them. The tracking studies led to the establishment of the injected beam parameters and rf voltage program that minimized beam loss and longitudinal instabilities. Similar studies for a 10-GeV synchrotron that uses the 2-GeV synchrotron as its injector are also discussed. {copyright} {ital 1996 American Institute of Physics.}

  3. Simple modification of Compton polarimeter to redirect synchrotron radiation

    Directory of Open Access Journals (Sweden)

    J. Benesch

    2015-11-01

    Full Text Available Synchrotron radiation produced as an electron beam passes through a bending magnet is a significant source of background in many experiments. Using modeling, we show that simple modifications of the magnet geometry can reduce this background by orders of magnitude in some circumstances. Specifically, we examine possible modifications of the four dipole magnets used in Jefferson Lab’s Hall A Compton polarimeter chicane. This Compton polarimeter has been a crucial part of experiments with polarized beams and the next generation of experiments will utilize increased beam energies, up to 11 GeV, requiring a corresponding increase in Compton dipole field to 1.5 T. In consequence, the synchrotron radiation (SR from the dipole chicane will be greatly increased. Three possible modifications of the chicane dipoles are studied; each design moves about 2% of the integrated bending field to provide a gentle bend in critical regions along the beam trajectory which, in turn, greatly reduces the synchrotron radiation within the acceptance of the Compton polarimeter photon detector. Each of the modifications studied also softens the SR energy spectrum at the detector sufficiently to allow shielding with 5 mm of lead. Simulations show that these designs are each capable of reducing the background signal due to SR by three orders of magnitude. The three designs considered vary in their need for vacuum vessel changes and in their effectiveness.

  4. High-precision simulation of slow-extraction spill from a hadrontherapy synchrotron

    Science.gov (United States)

    Méot, F.

    2008-10-01

    This report reviews the reconstruction, by means of multiturn, stepwise ray-tracing, of a slow-extracted particle beam from a synchrotron. The goal is to show that very precise descriptions of the transverse beam densities and the slow-spill intensity, which are crucial parameters in hadrontherapy, can be obtained in this way.

  5. High-precision simulation of slow-extraction spill from a hadrontherapy synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [CEA and IN2P3, LPSC, 53 Avenue des Marturs, 38026 Grenoble (France)], E-mail: meot@lpsc.in2p3.fr

    2008-10-11

    This report reviews the reconstruction, by means of multiturn, stepwise ray-tracing, of a slow-extracted particle beam from a synchrotron. The goal is to show that very precise descriptions of the transverse beam densities and the slow-spill intensity, which are crucial parameters in hadrontherapy, can be obtained in this way.

  6. Design study for a 500 MeV proton synchrotron with CSNS linac as an injector

    Science.gov (United States)

    Huang, Liang-Sheng; Ji, Hong-Fei; Wang, Sheng

    2016-09-01

    Using the China Spallation Neutron Source (CSNS) linac as the injector, a 500 MeV proton synchrotron is proposed for multidisciplinary applications, such as biology, material science and proton therapy. The synchrotron will deliver proton beam with energy from 80 MeV to 500 MeV. A compact lattice design has been worked out, and all the important beam dynamics issues have been investigated. The 80 MeV H- beam is stripped and injected into the synchrotron by using multi-turn injection. In order to continuously extraction the proton with small beam loss, an achromatic structure is proposed and a slow extraction method with RF knock-out is adopted and optimized.

  7. Mono-Energy Coronary Angiography with a Compact Synchrotron Source

    Science.gov (United States)

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

    2017-02-01

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

  8. 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.

  9. A High-Speed Optical Modem Communication System for CORK Seafloor Observatories

    Science.gov (United States)

    Farr, N.; Tivey, M.; Ware, J.; Pontbriand, C.; Pelletier, L. P.

    2014-12-01

    High-speed communications underwater is an increasing requirement for data intensive seafloor sensors. Acoustic modems provide dependable long-range communications underwater, but data rates are limited to ship with an SDSL link over the conducting wire. Other methods utilized OMs mounted to both ROV Jason and submersible Alvin. We deployed OMs at two CORKs in 2012 in the northeast pacific at sites 857D and 1025C. The CORKs were visited in 2013 by a vessel of opportunity to download data and were put into sleep mode. The CORKs were revisited in 2014, woken up and successfully interrogated for data. ALVIN retrieved the CORK-OMs for corrosion, biofouling and battery performance assessment. We also performed tests of a next generation OM using a deployed seafloor modem and AUV Sentry. A complete lambertian optical field was quantitatively mapped by Sentry and test data was successfully downloaded from 20 to 150 m slant range. The AUV modality demonstrates the capability of 'data-mule' operations to autonomously recover data from a seafloor observatory with minimal human intervention.

  10. Micro-beam XRF localization by a laser beam

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    A new method for micro-beam XRF localization is presented. A laserbeam along with an incident X-ray hits on the surface of a sample. The micro region onthe sample that reached by X-ray beam can be localized by means of thevisible spot of the laser beam. This method is suitable for X-ray microprobesusing anX-ray tube or synchrotron radiation as excitation sources.

  11. 现代企业情报工作的内容及方法%The Content & Method of Information Services of Modem Enterprises

    Institute of Scientific and Technical Information of China (English)

    尹怀琼

    2002-01-01

    The article discusses the content and method of information services of modem enterprises, including competitive intelligence, defensive competitive intelligence and the formulation of competitive strategies.

  12. An Ultra-Low Power and Flexible Acoustic Modem Design to Develop Energy-Efficient Underwater Sensor Networks

    Directory of Open Access Journals (Sweden)

    Antonio Sánchez

    2012-05-01

    Full Text Available This paper is focused on the description of the physical layer of a new acoustic modem called ITACA. The modem architecture includes as a major novelty an ultra-low power asynchronous wake-up system implementation for underwater acoustic transmission that is based on a low-cost off-the-shelf RFID peripheral integrated circuit. This feature enables a reduced power dissipation of 10 µW in stand-by mode and registers very low power values during reception and transmission. The modem also incorporates clear channel assessment (CCA to support CSMA-based medium access control (MAC layer protocols. The design is part of a compact platform for a long-life short/medium range underwater wireless sensor network.

  13. An ultra-low power and flexible acoustic modem design to develop energy-efficient underwater sensor networks.

    Science.gov (United States)

    Sánchez, Antonio; Blanc, Sara; Yuste, Pedro; Perles, Angel; Serrano, Juan José

    2012-01-01

    This paper is focused on the description of the physical layer of a new acoustic modem called ITACA. The modem architecture includes as a major novelty an ultra-low power asynchronous wake-up system implementation for underwater acoustic transmission that is based on a low-cost off-the-shelf RFID peripheral integrated circuit. This feature enables a reduced power dissipation of 10 μW in stand-by mode and registers very low power values during reception and transmission. The modem also incorporates clear channel assessment (CCA) to support CSMA-based medium access control (MAC) layer protocols. The design is part of a compact platform for a long-life short/medium range underwater wireless sensor network.

  14. An Ultra-Low Power and Flexible Acoustic Modem Design to Develop Energy-Efficient Underwater Sensor Networks

    Science.gov (United States)

    Sánchez, Antonio; Blanc, Sara; Yuste, Pedro; Perles, Angel; Serrano, Juan José

    2012-01-01

    This paper is focused on the description of the physical layer of a new acoustic modem called ITACA. The modem architecture includes as a major novelty an ultra-low power asynchronous wake-up system implementation for underwater acoustic transmission that is based on a low-cost off-the-shelf RFID peripheral integrated circuit. This feature enables a reduced power dissipation of 10 μW in stand-by mode and registers very low power values during reception and transmission. The modem also incorporates clear channel assessment (CCA) to support CSMA-based medium access control (MAC) layer protocols. The design is part of a compact platform for a long-life short/medium range underwater wireless sensor network. PMID:22969324

  15. Bystander Effects During Synchrotron Imaging Procedures?

    Science.gov (United States)

    Schültke, Elisabeth; Bewer, Brian; Wysokinski, Tomasz; Chapman, Dean; Nikkhah, Guido

    2010-07-01

    Using monochromatic beam and synchrotron phase-contrast technique at the biomedical beamline of the Italian synchrotron facility Elettra (SYRMEP), we have shown in a small animal model of malignant brain tumor that it is possible to obtain high-resolution images of very small tumors when they have developed from implanted tumor cells loaded with colloidal gold nanoparticles (GNP). All previous experiments were conducted in post-mortem samples. We have now designed a cell culture experiment to investigate the effects of synchrotron radiation with an energy and dose profile similar to that expected in our first in vivo imaging studies according to the protocol developed at SYRMEP. Materials and Methods: Culture flasks containing either gold-loaded or naïve C6 glioma cells were exposed to a dose of 0.5 Gy at 24 keV. The irradiated medium was aspirated and replaced with fresh growth medium. Twenty-four hours later this non-irradiated medium exposed to irradiated cells was aspirated, then added to non-irradiated C6 cells in order to investigate whether bystander effects are seen under the conditions of our image acquisition protocol. The irradiated medium was added to a number of other non-irradiated cell cultures. Cell counts were followed until 72 hrs after irradiation. Western blots were conducted with H2AX antibodies. This experiment was one of the first biomedical experiments conducted at BMIT, the new biomedical imaging and therapy beamline of the Canadian Light Source. Results: No significant differences in proliferation were seen between cells that were directly irradiated, exposed to irradiated medium or exposed to the non-irradiated 24-hr-medium from the irradiated cells. However, there was a tendency towards a higher number of double strand breaks in previously irradiated cells when they were exposed to non-irradiated medium that had been in contact with irradiated cells for 24 hrs.

  16. Anticlastic curvature measurements on unribbed crystal optics for synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Quintana, J.P.; Dolin, Y.; Georgopoulos, P. (DND-CAT Synchrotron Research Center, APS/ANL Sector 5, Building 400, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)); Kushnir, V.I. (APS/XFD, Bldg. 362, 9700 South Cass Ave., Argonne, Illinois 60439 (United States))

    1995-02-01

    Various methods have been proposed for measuring the distortion in perfect crystals using double-crystal methods. The majority of these methods rely on making comparisons between double-crystal rocking curve measurements under the spatial extent of an extended x-ray beam. Unless the beam is large and parallel (such as at a synchrotron bending magnet), these methods are not easily scalable to large crystals (e.g., crystal focusing elements for synchrotron beamlines) due to the mechanical inaccuracies inherent in moving the various optical components. We present a method based on a scanning source which simplifies the problems in scaling double-crystal methods to large optics. In addition, results using this method are presented on a ribless sagittal focusing Si(111) crystal demonstrating that the anticlastic deviation can be made to be less than [plus minus]1 s of arc over a 1-cm-long section parallel to the sagittal axis.

  17. Reshuffle lifts French synchrotron hopes

    CERN Multimedia

    McCabe, H

    2000-01-01

    The sacking of Claude Allegre as research minister has raised doubts over the level of France's promised participation in the construction of Diamond but reawakened French hopes that the synchrotron Soleil may now be built (1 page).

  18. Regions compete for French synchrotron

    CERN Multimedia

    2000-01-01

    Ten regions in France have placed bids to host the planned national synchrotron Soleil. Leading contenders include a joint bid from Ile-de-France and Essonne for Orsay, offering FF 1 billion towards the construction costs (2 paragraphs).

  19. Synchrotron radiation techniques for the characterization of $Nb_{3}Sn$ superconductors

    CERN Document Server

    Scheuerlein, C; Buta, F; Reichert, H; Thilly, L

    2009-01-01

    The high flux of high energy x-rays that can be provided through state-of-the-art high energy synchrotron beam lines has enabled a variety of new experiments with the highly absorbing Nb3Sn superconductors. We report different experiments with Nb3Sn strands that have been conducted at the ID15 High Energy Scattering beam line of the European Synchrotron Radiation Facility (ESRF). Synchrotron x-ray diffraction has been used in order to monitor phase transformations during in-situ reaction heat treatments prior to Nb3Sn formation, and to monitor Nb3Sn growth. Fast synchrotron micro-tomography was applied to study void growth during the reaction heat treatment of Internal Tin strands. The elastic strain in the different phases of fully reacted Nb3Sn composite conductors can be measured by high resolution x-ray diffraction during in-situ tensile tests.

  20. Multiple energy synchrotron biomedical imaging system

    Science.gov (United States)

    Bassey, B.; Martinson, M.; Samadi, N.; Belev, G.; Karanfil, C.; Qi, P.; Chapman, D.

    2016-12-01

    A multiple energy imaging system that can extract multiple endogenous or induced contrast materials as well as water and bone images would be ideal for imaging of biological subjects. The continuous spectrum available from synchrotron light facilities provides a nearly perfect source for multiple energy x-ray imaging. A novel multiple energy x-ray imaging system, which prepares a horizontally focused polychromatic x-ray beam, has been developed at the BioMedical Imaging and Therapy bend magnet beamline at the Canadian Light Source. The imaging system is made up of a cylindrically bent Laue single silicon (5,1,1) crystal monochromator, scanning and positioning stages for the subjects, flat panel (area) detector, and a data acquisition and control system. Depending on the crystal’s bent radius, reflection type, and the horizontal beam width of the filtered synchrotron radiation (20-50 keV) used, the size and spectral energy range of the focused beam prepared varied. For example, with a bent radius of 95 cm, a (1,1,1) type reflection and a 50 mm wide beam, a 0.5 mm wide focused beam of spectral energy range 27 keV-43 keV was obtained. This spectral energy range covers the K-edges of iodine (33.17 keV), xenon (34.56 keV), cesium (35.99 keV), and barium (37.44 keV) some of these elements are used as biomedical and clinical contrast agents. Using the developed imaging system, a test subject composed of iodine, xenon, cesium, and barium along with water and bone were imaged and their projected concentrations successfully extracted. The estimated dose rate to test subjects imaged at a ring current of 200 mA is 8.7 mGy s-1, corresponding to a cumulative dose of 1.3 Gy and a dose of 26.1 mGy per image. Potential biomedical applications of the imaging system will include projection imaging that requires any of the extracted elements as a contrast agent and multi-contrast K-edge imaging.

  1. Control of synchrotron radiation effects during recirculation with bunch compression

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, David [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Benson, Stephen [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Yves [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, Christopher [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Krafft, Geoffrey [Old Dominion Univ., Norfolk, VA (United States); Terzic, Balsa [Old Dominion Univ., Norfolk, VA (United States); Tsai, Cheng [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

    2015-05-01

    Studies of beam quality during recirculation have been extended to an arc providing bunch compression with positive momentum compaction. It controls both incoherent and coherent synchrotron radiation (ISR and CSR) using methods including optics balance and generates little microbunching gain. We detail the dynamical basis for the design, discuss the design process, give an example, and provide simulations of ISR and CSR effects. Reference will be made to a complete analysis of microbunching effects.

  2. The European 400 GeV proton synchrotron

    CERN Document Server

    Middelkoop, Willem Cornelis

    1977-01-01

    On 19th February 1971, CERN decided to build a super proton synchrotron at a cost of 1150*10/sup 6/ Swiss francs. The design target of 400 GeV with a beam intensity of 10/sup 13/ protons/pulse was reached on the 4th of November 1976 within the original budget, allowing for inflation. The technical aspects of the SPS are reviewed, together with operating experience since May 1976. (2 refs).

  3. Injection Efficiency Monitor for the Australian Synchrotron

    Directory of Open Access Journals (Sweden)

    Rassool R. P.

    2012-10-01

    Full Text Available The Australian Synchrotron AS is moving towards a continuous injection mode called top-up. During top-up the linac and booster synchrotron injection system will be in continuous operation rather than usedevery eight hours the way they are used at present. In order to monitor the performance of the injection system areal-time injection efficiency monitoring system has been developed. The system consists of several Fast CurrentTransformers [1] and matching digitisers [2] and is designed to count every beam pulse and measure the transmission efficiency through the whole accelerator complex. After calibrating the system using a properly matchedFaraday Cup at the electron gun, a transmission efficiency is then calculated at each stage of transferring the beamfrom 90 keV out of the gun to 3 GeV in the storage ring. The system is used to optimise the injection process inorder to maximise the injection efficiency and as an early warning system when equipment starts to fail and theinjection efficiency decreases.

  4. 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...

  5. KEKB beam instrumentation systems

    Science.gov (United States)

    Arinaga, M.; Flanagan, J.; Hiramatsu, S.; Ieiri, T.; Ikeda, H.; Ishii, H.; Kikutani, E.; Mimashi, T.; Mitsuhashi, T.; Mizuno, H.; Mori, K.; Tejima, M.; Tobiyama, M.

    2003-02-01

    For the stable high-luminosity operation and luminosity increase, the electron and positron storage rings of the KEK B-Factory (KEKB) is equipped with various beam instrumentations, which have been working well since the start of the commissioning in December, 1998. Details and performance of the beam-position monitor system based on the spectrum analysis using DSPs, the turn-by-turn BPM with four-dimensional function available for measurements of the individual bunch position, phase and intensity, the parametric beam-DCCTs designed so as to avoid the magnetic-core-selection problems for the parametric flux modulation, the bunch-by-bunch feedback system indispensable to suppress the strong multibunch instabilities in KEKB, the various optical beam diagnostic systems, such as synchrotron radiation interferometers for precise beam-size measurement, the tune meters, the bunch length monitors and the beam-loss monitors are described. Delicate machine tuning of KEKB is strongly supported by these instrumentations.

  6. Beam instrumentation performance overview

    CERN Document Server

    Sapinski, M

    2012-01-01

    The 2011 run has proven that LHC can operate safely and stably with higher bunch intensity and smaller transverse emittance than foreseen in the Technical Design Report. In this presentation the performance of the Beam Position Monitoring (BPM) system is discussed. The improvements to the system, those made during the last year and those expected to be done for 2012 run are presented. The status of the three types of devices measuring the transverse beam emittance, wire scanners (BWS), synchrotron radiation monitors (BSRT) and beam gas ionization monitors (BGI), are shown. The control room applications are reviewed and a set of improvements proposed by the operation team is presented.

  7. The AGS synchrotron with four helical magnets

    Energy Technology Data Exchange (ETDEWEB)

    Tsoupas N.; Huang, H.; Roser, T.; MacKay, W.W.; Trbojevic, D.

    2012-05-20

    The idea of using two partial helical magnets was applied successfully to the AGS synchrotron to preserve the proton beam polarization. In this paper we explore in details the idea of using four helical magnets placed symmetrically in the AGS ring. The placement of four helical magnets in the AGS ring provides many advantages over the present setup of the AGS which uses two partial helical magnets. First, the symmetric placement of the four helical magnets allows for a better control of the AGS optics with reduced values of the beta functions especially near beam injection, second, the vertical spin direction during beam injection and extraction is closer to vertical, and third, it provides for a larger 'spin tune gap', which allows the vertical and horizontal tunes to be placed, and prevent the horizontal and vertical intrinsic spin resonances of the AGS to occur during the acceleration cycle. Although the same spin gap can be obtained with a single or two partial helices, the required high field strength of a single helix makes its use impractical, and that of the double helix rather difficult. In this paper we will provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and compare these results with the present setup of the AGS that uses two partial helical magnets.

  8. Machine detector interface studies: Layout and synchrotron radiation estimate in the future circular collider interaction region

    CERN Document Server

    Boscolo, Manuela; Sullivan, Michael Kenneth

    2017-01-01

    The interaction region layout for the e$^+$e$^−$ future circular collider FCC-ee is presented together with a preliminary estimate of synchrotron radiation that affects this region. We describe in this paper the main guidelines of this design and the estimate of synchrotron radiation coming from the last bending magnets and from the final focus quadrupoles, with the software tools developed for this purpose. The design follows the asymmetric optics layout as far as incoming bend radiation is concerned with the maximum foreseen beam energy of 175 GeV and we present a feasible initial layout with an indication of tolerable synchrotron radiation.

  9. Machine detector interface studies: Layout and synchrotron radiation estimate in the future circular collider interaction region

    Directory of Open Access Journals (Sweden)

    Manuela Boscolo

    2017-01-01

    Full Text Available The interaction region layout for the e^{+}e^{-} future circular collider FCC-ee is presented together with a preliminary estimate of synchrotron radiation that affects this region. We describe in this paper the main guidelines of this design and the estimate of synchrotron radiation coming from the last bending magnets and from the final focus quadrupoles, with the software tools developed for this purpose. The design follows the asymmetric optics layout as far as incoming bend radiation is concerned with the maximum foreseen beam energy of 175 GeV and we present a feasible initial layout with an indication of tolerable synchrotron radiation.

  10. Machine detector interface studies: Layout and synchrotron radiation estimate in the future circular collider interaction region

    Science.gov (United States)

    Boscolo, Manuela; Burkhardt, Helmut; Sullivan, Michael

    2017-01-01

    The interaction region layout for the e+e- future circular collider FCC-ee is presented together with a preliminary estimate of synchrotron radiation that affects this region. We describe in this paper the main guidelines of this design and the estimate of synchrotron radiation coming from the last bending magnets and from the final focus quadrupoles, with the software tools developed for this purpose. The design follows the asymmetric optics layout as far as incoming bend radiation is concerned with the maximum foreseen beam energy of 175 GeV and we present a feasible initial layout with an indication of tolerable synchrotron radiation.

  11. 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...

  12. 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.

  13. Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Keith W.

    1999-09-01

    Elemental analysis using emission of characteristic x rays is a well-established scientific method. The success of this analytical method is highly dependent on the properties of the source used to produce the x rays. X-ray tubes have long existed as a principal excitation source, but electron and proton beams have also been employed extensively. The development of the synchrotron radiation x-ray source that has taken place during the past 40 years has had a major impact on the general field of x-ray analysis. Even tier 40 years, science of x-ray analysis with synchrotron x-ray beams is by no means mature. Improvements being made to existing synchrotron facilities and the design and construction of new facilities promise to accelerate the development of the general scientific use of synchrotron x-ray sources for at least the next ten years. The effective use of the synchrotron source technology depends heavily on the use of high-performance computers for analysis and theoretical interpretation of the experimental data. Fortunately, computer technology has advanced at least as rapidly as the x-ray technology during the past 40 years and should continue to do so during the next decade. The combination of these technologies should bring about dramatic advances in many fields where synchrotron x-ray science is applied. It is interesting also to compare the growth and rate of acceptance of this particular research endeavor to the rates for other technological endeavors. Griibler [1997] cataloged the time required for introduction, diffusion,and acceptance of technological, economic, and social change and found mean values of 40 to 50 years. The introduction of the synchrotron source depends on both technical and non-technical factors, and the time scale at which this seems to be occurring is quite compatible with what is seen for other major innovations such as the railroad or the telegraph. It will be interesting to see how long the present rate of technological change

  14. Brightness of synchrotron radiation from wigglers

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-12-15

    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. In the geometrical optics limit computations can be performed analytically. Within this limit, we restrict ourselves to the case of the beam size-dominated regime, which is typical for synchrotron radiation facilities in the X-ray wavelength range. We give a direct demonstration of the fact that the apparent horizontal source size is broadened in proportion to the beamline opening angle and to the length of the wiggler. While this effect is well-understood, a direct proof appears not to have been given elsewhere. We consider the problem of the calculation of the wiggler source size by means of numerical simulations alone, which play the same role of an experiment. We report a significant numerical disagreement between exact calculations and approximations currently used in literature.

  15. Pemrograman Antarmuka Modem GSM dengan Pengendali Mikro AVR Menggunakan Bahasa C

    Directory of Open Access Journals (Sweden)

    Daniel Kartawiguna

    2011-12-01

    Full Text Available Cell phones are now a cheap means of wide-ranged wireless communication. One feature widely used is the short message service (SMS. The cellular communication system is more appropriate for long-distanced applications than high speed data transfer. This study aims to develop a GSM modem interface with AVR microcontroller using C programming language. The tools controlled by the microcontroller system can gain more benefit if it is linked with GSM mobile communication system. The results of this study can be applied whether in a remote monitoring system, remote control system, or communication between the microcontroller via SMS. Many additional benefits can be obtained for the tools controlled by the microcontroller when connected to a GSM system. 

  16. Development of a PLC modem for data transmission over a PWM power supply

    Science.gov (United States)

    Batard, Christophe; Ginot, Nicolas; Mannah, Marc Anthony; Millet, Christophe; Poitiers, Frédéric

    2014-04-01

    In variable-speed electrical drive and online conditioning monitoring, a feedback loop is required in order to transmit the sensor information from the motor to the controller close to the inverter. Additional cabling is used for signalling. This extra cabling has a significant cost and data transmission may not be reliable. Thus, the use of power line communication (PLC) technology to transmit data in motor drive application is quite interesting. The use of a PLC modem dedicated to the home network in a three-phase inverter-fed motor power cable does not work. Therefore, specific coupling interfaces are developed to transmit data through a pulse-width modulated power supply. Laboratory tests have shown that the couplers are operating properly. They ensure reliable data transmission in a motor drive application.

  17. MODEM: a multi-agent hierarchical structure to model the human motor control system.

    Science.gov (United States)

    Emadi Andani, Mehran; Bahrami, Fariba; Jabehdar Maralani, Parviz; Ijspeert, Auke Jan

    2009-12-01

    In this study, based on behavioral and neurophysiological facts, a new hierarchical multi-agent architecture is proposed to model the human motor control system. Performance of the proposed structure is investigated by simulating the control of sit to stand movement. To develop the model, concepts of mixture of experts, modular structure, and some aspects of equilibrium point hypothesis were brought together. We have called this architecture MODularized Experts Model (MODEM). Human motor system is modeled at the joint torque level and the role of the muscles has been embedded in the function of the joint compliance characteristics. The input to the motor system, i.e., the central command, is the reciprocal command. At the lower level, there are several experts to generate the central command to control the task according to the details of the movement. The number of experts depends on the task to be performed. At the higher level, a "gate selector" block selects the suitable subordinate expert considering the context of the task. Each expert consists of a main controller and a predictor as well as several auxiliary modules. The main controller of an expert learns to control the performance of a given task by generating appropriate central commands under given conditions and/or constraints. The auxiliary modules of this expert learn to scrutinize the generated central command by the main controller. Auxiliary modules increase their intervention to correct the central command if the movement error is increased due to an external disturbance. Each auxiliary module acts autonomously and can be interpreted as an agent. Each agent is responsible for one joint and, therefore, the number of the agents of each expert is equal to the number of joints. Our results indicate that this architecture is robust against external disturbances, signal-dependent noise in sensory information, and changes in the environment. We also discuss the neurophysiological and behavioral basis of

  18. Hard X-ray Sources for the Mexican Synchrotron Project

    Science.gov (United States)

    Reyes-Herrera, Juan

    2016-10-01

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

  19. Design and Performance of the Upgraded LHC Synchrotron Light Monitor

    CERN Document Server

    Goldblatt, A; Roncarolo, F; Trad, G

    2013-01-01

    The LHC is equipped with two synchrotron radiation systems, one per beam, used to measure the transverse bunch distributions. The light emitted by a superconducting undulator and/or by a dipole magnet (depending on beam energy) is intercepted by an extraction mirror in vacuum and sent through a viewport to the imaging Beam Synchrotron Radiation Telescope (BSRT). The first version of the telescope, used from 2009 to mid 2012, was based on spherical focusing mirrors in order to minimize chromatic aberrations. However, this required a very complicated delay line in order to switch the focus between the two different light sources as a function of beam energy. A new system based on optical lenses was designed and installed in mid 2012 in order to simplify the optical line and thus reduce misalignment and focusing errors. The first results with LHC beam using this new system showed a significant reduction in the correction factor required to match the emittance as measured by wire scanners. This contribution discu...

  20. Compensating effect of the coherent synchrotron radiation in bunch compressors

    Directory of Open Access Journals (Sweden)

    Yichao Jing

    2013-06-01

    Full Text Available Typical bunch compression for a high-gain free-electron laser (FEL requires a large compression ratio. Frequently, this compression is distributed in multiple stages along the beam transport line. However, for a high-gain FEL driven by an energy recovery linac (ERL, compression must be accomplished in a single strong compressor located at the beam line’s end; otherwise the electron beam would be affected severely by coherent synchrotron radiation (CSR in the ERL’s arcs. In such a scheme, the CSR originating from the strong compressors could greatly degrade the quality of the electron beam. In this paper, we present our design for a bunch compressor that will limit the effect of CSR on the e-beam’s quality. We discuss our findings from a study of such a compressor, and detail its potential for an FEL driven by a multipass ERL developed for the electron-Relativistic Heavy Ion Collider.

  1. 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...

  2. Commissioning of a compact synchrotron radiation source at Hiroshima University

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, K.; Andreyashkin, M.; Goto, K. [Hiroshima Univ. (Japan)] [and others

    1998-11-01

    A 700 MeV synchrotron radiation source is under commissioning at Hiroshima University. The ring is of a racetrack type with two undulators, linear and helical ones, at the long straight sections. The bending field, produced by normal conducting magnet, is as strong as 2.7 Tesla, which generates as high radiation power as compatible with the one from usual 1.6 GeV ring. 14 beam-ports from the bending sections together with two from the undulators are prepared. The injector is a 150 MeV racetrack microtron, which is used also for other purposes than the beam injection into the storage ring. As of March 1998, the stored current is typically 100 mA at start and the beam lifetime is three hours. We expect the beam lifetime will be extended to be eight hours after degassing operation for another few months. (author)

  3. The optimization for the conceptual design of a 300 MeV proton synchrotron

    CERN Document Server

    An, Yuwen; Wang, Sheng; Huang, Liangsheng

    2016-01-01

    A research complex for aerospace radiation effects research has been proposed in Harbin Institute of Technology. Its core part is a proton accelerator complex, which consists of a 10 MeV injector, a 300 MeV synchrotron and beam transport lines. The proton beam extracted from the synchrotron is utilized for the radiation effects research. Based on the conceptual design [1], the design study for optimizing the synchrotron has been done. A new lattice design was worked out, and the multi-turn injection and slow extraction system were optimized with the new lattice design. In order to improve the time structure of the extracted beam, a RF knock-out method is employed. To meet the requirement of accurate control of dose, the frequency of the RF kicker is well investigated.

  4. LATTICES FOR HIGH-POWER PROTON BEAM ACCELERATION AND SECONDARY BEAM COLLECTION AND COOLING.

    Energy Technology Data Exchange (ETDEWEB)

    WANG, S.; WEI, J.; BROWN, K.; GARDNER, C.; LEE, Y.Y.; LOWENSTEIN, D.; PEGGS, S.; SIMOS, N.

    2006-06-23

    Rapid cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: (a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics (b) long straight sections for low-loss injection, extraction, and high-efficiency collimation (c) dispersion-free straights to avoid longitudinal-transverse coupling, and (d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.

  5. Towards synchrotron-based nanocharacterization

    Science.gov (United States)

    Bleuet, Pierre; Arnaud, Lucile; Biquard, Xavier; Cloetens, Peter; Doyen, Lise; Gergaud, Patrice; Lamontagne, Patrick; Lavayssière, Maylis; Micha, Jean-Sébastien; Renault, Olivier; Rieutord, François; Susini, Jean; Ulrich, Olivier

    2009-09-01

    The advent of 3rd generation synchrotron sources coupled with high efficiency x-ray focusing optics opened new nanocharacterization possibilities. This paper is an overview of synchrotron-based techniques that may be of interest for nanotechnology researchers. Although not exhaustive, it includes a general background of synchrotron principle and main x-ray interactions before addressing nanoimaging possibilities. Three-dimensional (3D) hard x-ray multimodal tomography is now doable that allows producing 3D morphological, chemical and crystalline images with a sub-100 nm resolution. Although the resolution is still limited with respect to electron imaging, it presents attractive features like depth resolution and non-destructive exam. Besides imaging, diffraction also allows strain determination within microstructures and is illustrated here on 100 nm copper lines. Surface analysis is illustrated through X-ray Photoelectron Emission Microscopy (XPEEM).

  6. Detection and spectral measurements of coherent synchrotron radiation at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, Christopher

    2010-02-15

    The operation of high-gain free-electron laser (FEL) underlies tremendous demands on high quality electron beams with high peak currents. At the Free-Electron-Laser in Hamburg (FLASH), two magnetic bunch compressors are used to compress the electron bunches longitudinally. In the bunch compressor magnets, these short electron bunches generate coherent synchrotron radiation (CSR). This CSR contains information on the longitudinal bunch profile, which is relevant for driving an FEL. In order to investigate coherent synchrotron radiation at the second bunch compressor BC3 at FLASH, a new setup behind the last dipole was installed. For the detection of coherent synchrotron radiation, which is emitted in the infrared regime, pyroelectric detectors were used. These pyroelectric detectors have been calibrated at the free-electron laser FELIX in the wavelength range from 5 {mu}m to 110 {mu}m. For characterisation of the emitted radiation, a transverse scanning device was used to measure the transverse intensity distribution. Various transmission filters were used to obtain additional information about the spectral content. In order to get spectral information with high resolution over a wide wavelength range, a rotating mirror spectrometer using reflective blazed gratings was installed. Using this spectrometer, the first spectral measurements of coherent synchrotron radiation at FLASH in a wavelength range from 10 {mu}m to 160 {mu}m were done. (orig.)

  7. Synchrotron Radiation in eRHIC Interaction Region

    CERN Document Server

    Beebe-Wang, Joanne; Montag, Christoph; Rondeau, Daniel J; Surrow, Bernd

    2005-01-01

    The eRHIC currently under study at BNL consists of an electron storage ring added to the existing RHIC complex. The interaction region of this facility has to provide the required low-beta focusing while accommodating the synchrotron radiation generated by beam separation close to the interaction point. In the current design, the synchrotron radiation caused by 10GeV electrons bent by low-beta triplet magnets will be guided through the interaction region and dumped 5m downstream. However, it is unavoidable to stop a fraction of the photons at the septum where the electron and ion vacuum system are separated. In order to protect the septum and minimize the backward scattering of the synchrotron radiation, an absorber and collimation system will be employed. In this paper, we first present the overview of the current design of the eRHIC interaction region with special emphasis on the synchrotron radiation. Then the initial design of the absorber and collimation system, including their geometrical and physical p...

  8. 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.

  9. Heavy Ion Injection Into Synchrotrons, Based On Electron String Ion Sources

    CERN Document Server

    Donets, E E; Syresin, E M

    2004-01-01

    A possibility of heavy ions injection into synchrotrons is discussed on the base of two novel ion sources, which are under development JINR during last decade: 1) the electron string ion source (ESIS), which is a modified version of a conventional electron beam ion source (EBIS), working in a reflex mode of operation, and 2) the tubular electron string ion source (TESIS). The Electron String Ion Source "Krion-2" (VBLHE, JINR, Dubna) with an applied confining magnetic field of 3 T was used for injection into the superconducting JINR synchrotron - Nuclotron and during this runs the source provided a high pulse intensity of the highly charged ion beams: Ar16+

  10. Synchrotron X-ray CT characterization of titanium parts fabricated by additive manufacturing. Part I. Morphology.

    Science.gov (United States)

    Scarlett, Nicola Vivienne Yorke; Tyson, Peter; Fraser, Darren; Mayo, Sheridan; Maksimenko, Anton

    2016-07-01

    Synchrotron X-ray tomography has been applied to the study of titanium parts fabricated by additive manufacturing (AM). The AM method employed here was the Arcam EBM(®) (electron beam melting) process which uses powdered titanium alloy, Ti64 (Ti alloy with approximately 6%Al and 4%V), as the feed and an electron beam for the sintering/welding. The experiment was conducted on the Imaging and Medical Beamline of the Australian Synchrotron. Samples were chosen to examine the effect of build direction and complexity of design on the surface morphology and final dimensions of the piece.

  11. 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.

  12. Current advances in synchrotron radiation instrumentation for MX experiments

    Energy Technology Data Exchange (ETDEWEB)

    Owen, Robin L.; Juanhuix, Jordi; Fuchs, Martin

    2016-07-01

    Following pioneering work 40 years ago, synchrotron beamlines dedicated to macromolecular crystallography (MX) have improved in almost every aspect as instrumentation has evolved. Beam sizes and crystal dimensions are now on the single micron scale while data can be collected from proteins with molecular weights over 10 MDa and from crystals with unit cell dimensions over 1000 Å. Furthermore it is possible to collect a complete data set in seconds, and obtain the resulting structure in minutes. The impact of MX synchrotron beamlines and their evolution is reflected in their scientific output, and MX is now the method of choice for a variety of aims from ligand binding to structure determination of membrane proteins, viruses and ribosomes, resulting in a much deeper understanding of the machinery of life. A main driving force of beamline evolution have been advances in almost every aspect of the instrumentation comprising a synchrotron beamline. In this review we aim to provide an overview of the current status of instrumentation at modern MX experiments. The most critical optical components are discussed, as are aspects of endstation design, sample delivery, visualisation and positioning, the sample environment, beam shaping, detectors and data acquisition and processing.

  13. Status of the IUCF Cooler Injector Synchrotron Construction Project

    Science.gov (United States)

    Friesel, D. L.; Lee, S. Y.

    1997-05-01

    Construction of a 2.24 T-m, rapid-cycling booster synchrotron is nearing completion at IUCF. The synchrotron is designed to accelerate protons to 220 MeV and will replace the IUCF isochronous cyclotrons as an injector of polarized light ion beams into the 3.6 T-m electron-cooled storage ring. CIS (Cooler Injector Synchrotron), with a circumference of 1/5th the Cooler ring, will fill the Cooler to about 10^11 protons via ``boxcar" stacking in a few seconds for research. The compact booster design, which can accelerate protons to energies between 60 and 220 MeV, is also well suited for use in proton therapy applications. At 28 months into the construction program, all major ring elements (dipoles, quads, injector linac, RF system) are fabricated, assembled, installed and in some cases, commissioned. Ring beam injection and ramping studies are scheduled to start in May, 1997 and Cooler injection studies are planned for late 1997. The booster design properties, component commissioning results and construction completion schedule will be summarized.

  14. Electron cloud observations at the ISIS Proton Synchrotron

    CERN Document Server

    Pertica, A

    2013-01-01

    The build up of electron clouds inside a particle accelerator vacuum chamber can produce strong transverse and longitudinal beam instabilities which in turn can lead to high levels of beam loss often requiring the accelerator to be run below its design specification. To study the behaviour of electron clouds at the ISIS Proton Synchrotron, a Micro-Channel Plate (MCP) based electron cloud detector has been developed. The detector is based on the Retarding Field Analyser (RFA) design and consists of a retarding grid, which allows energy analysis of the electron signal, and a MCP assembly placed in front of the collector plate. The MCP assembly provides a current gain over the range 300 to 25K, thereby increasing the signal to noise ratio and dynamic range of the measurements. This paper presents the first electron cloud observations at the ISIS Proton Synchrotron. These results are compared against signals from a beam position monitor and a fast beam loss monitor installed at the same location.

  15. Scaling Behavior of Circular Colliders Dominated by Synchrotron Radiation

    CERN Document Server

    Talman, Richard

    2015-01-01

    The quite low Higgs particle mass makes it natural for the next high energy facility to be a circular e+e- Higgs factory and, after that, a next-generation p,p collider in the same tunnel. Surveying the luminosity-limiting phenomena of synchrotron radiation power loss, beam-beam interaction limitations, and beamstrahlung, scaling laws are established that fix all parameters of the Higgs factory, as functions of assumed radius $r$, and RF power $P$. at least to a first approximation. Historically the accelerator formalisms of electron and hadron rings have been distinguished largely by the importance of synchrotron radiation for electrons, and its unimportance for protons. While electron beams equilibrate within seconds, proton beam distributions have survived largely intact for extended periods. For future hadron colliders, this distinction will no longer be valid. This will have a large impact on the design of the future FCC-pp proton collider whose parameters can be extrapolated using formulas previously ap...

  16. Optical systems for synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Howells, M.R.

    1985-12-01

    Various fundamental topics which underlie the design and use of optical systems for synchrotron radiation are considered from the viewpoint of linear system theory. These topics include the damped harmonic oscillator, free space propagation of an optical field, electromagnetic theory of optical properties of materials, theory of dispersion, and the Kramers-Kronig relations. 32 refs., 5 figs. (LEW)

  17. 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.)

  18. Synchrotron radiation and biomedical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Luccio, A.

    1986-08-01

    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.

  19. Axion beams at HERA?

    OpenAIRE

    Piotrzkowski, Krzysztof

    2007-01-01

    If the recently observed anomaly in the PVLAS experiment is due to the axion, then the powerful beams of synchrotron photons, propagating through high magnetic field of the HERA beamline, become strong axion sources. This gives a unique opportunity of detection of the axion-photon interactions by installing a small detector in the HERA tunnel, and to corroborate the axion hypothesis within a few days of running. Comment: 5 pages, 1 figure

  20. Room-temperature macromolecular serial crystallography using synchrotron radiation

    Directory of Open Access Journals (Sweden)

    Francesco Stellato

    2014-07-01

    Full Text Available A new approach for collecting data from many hundreds of thousands of microcrystals using X-ray pulses from a free-electron laser has recently been developed. Referred to as serial crystallography, diffraction patterns are recorded at a constant rate as a suspension of protein crystals flows across the path of an X-ray beam. Events that by chance contain single-crystal diffraction patterns are retained, then indexed and merged to form a three-dimensional set of reflection intensities for structure determination. This approach relies upon several innovations: an intense X-ray beam; a fast detector system; a means to rapidly flow a suspension of crystals across the X-ray beam; and the computational infrastructure to process the large volume of data. Originally conceived for radiation-damage-free measurements with ultrafast X-ray pulses, the same methods can be employed with synchrotron radiation. As in powder diffraction, the averaging of thousands of observations per Bragg peak may improve the ratio of signal to noise of low-dose exposures. Here, it is shown that this paradigm can be implemented for room-temperature data collection using synchrotron radiation and exposure times of less than 3 ms. Using lysozyme microcrystals as a model system, over 40 000 single-crystal diffraction patterns were obtained and merged to produce a structural model that could be refined to 2.1 Å resolution. The resulting electron density is in excellent agreement with that obtained using standard X-ray data collection techniques. With further improvements the method is well suited for even shorter exposures at future and upgraded synchrotron radiation facilities that may deliver beams with 1000 times higher brightness than they currently produce.

  1. Beam instability Workshop - plenary sessions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The purpose of this workshop was to provide a review of the mechanisms of limiting beam instabilities, their cures, including feedback, and beam measurement for synchrotron radiation light sources. 12 plenary sessions took place whose titles are: 1) challenging brilliance and lifetime issues with increasing currents; 2) limiting instabilities in multibunch; 3) experience from high currents in B factories; 4) longitudinal dynamics in high intensity/bunch; 5) Transverse instabilities for high intensity/bunch; 6) working group introduction from ESRF experience; 7) impedance modelling: simulations, minimization; 8) report on the broadband impedance measurements and modelling workshop; 9) feedback systems for synchrotron light sources; 10) beam instabilities diagnostics; 11) harmonic cavities: the pros and cons; and 12) experimental study of fast beam-ion instabilities at PLS. This document gathers the 12 articles that were presented during these sessions.

  2. Time-resolved spectroscopy using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Poliakoff, E.D.

    1979-08-01

    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 Xe/sub 2/ system. It was found that even qualitative agreement of observed Xe/sub 2/ 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* (B/sup 2/..sigma../sup +/) and XeF* (B/sup 2/..sigma../sup +/ and C/sup 2/ Pi/sub 3/2//), were studied by pulsed photodissociation of stable parent compounds, ICN and XeF/sub 2/. When the polarization of the CN* (B/sup 2/..sigma../sup +/) 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.

  3. New synchrotron powder diffraction facility for long-duration experiments

    Science.gov (United States)

    Murray, Claire A.; Potter, Jonathan; Day, Sarah J.; Baker, Annabelle R.; Thompson, Stephen P.; Kelly, Jon; Morris, Christopher G.; Tang, Chiu C.

    2017-01-01

    A new synchrotron X-ray powder diffraction instrument has been built and commissioned for long-duration experiments on beamline I11 at Diamond Light Source. The concept is unique, with design features to house multiple experiments running in parallel, in particular with specific stages for sample environments to study slow kinetic systems or processes. The instrument benefits from a high-brightness X-ray beam and a large area detector. Diffraction data from the commissioning work have shown that the objectives and criteria are met. Supported by two case studies, the results from months of measurements have demonstrated the viability of this large-scale instrument, which is the world’s first dedicated facility for long-term studies (weeks to years) using synchrotron radiation. PMID:28190992

  4. Synchrotron-based FTIR spectromicroscopy: Cytotoxicity and heating considerations

    Energy Technology Data Exchange (ETDEWEB)

    Holman, Hoi-Ying N.; Martin, Michael C.; McKinney, Wayne R.

    2002-12-13

    Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectromicroscopy is a newly emerging bioanalytical and imaging tool. This unique technique provides mid-infrared (IR) spectra, hence chemical information, with high signal-to-noise at spatial resolutions as fine as 3 to 10 microns. Thus it enables researchers to locate, identify, and track specific chemical events within an individual living mammalian cell. Mid-IR photons are too low in energy (0.05 - 0.5 eV) to either break bonds or to cause ionization. In this review, we show that the synchrotron IR beam has no detectable effects on the short- and long-term viability, reproductive integrity, cell-cycle progression, and mitochondrial metabolism in living human cells, and produces only minimal sample heating (< 0.5 degrees C). These studies have established an important foundation for SR-FTIR spectromicroscopy in biological and biomedical research.

  5. A vacuum ultraviolet filtering monochromator for synchrotron-based spectroscopy

    Science.gov (United States)

    Janik, Ireneusz; Marin, Timothy W.

    2013-01-01

    We describe the design, characterization, and implementation of a vacuum ultraviolet (VUV) monochromator for use in filtering stray and scattered light from the principal monochromator output of the Stainless Steel Seya VUV synchrotron beam line at the Synchrotron Radiation Center, University of Wisconsin-Madison. We demonstrate a reduction of three orders of magnitude of stray and scattered light over the wavelength range 1400-2000 Å with minimal loss of light intensity, allowing for over six orders of magnitude of dynamic range in light detection. We suggest that a similar filtering scheme can be utilized in any variety of spectroscopic applications where a large dynamic range and low amount of background signal are of import, such as in transmittance experiments with very high optical density.

  6. Application of X-ray synchrotron microscopy instrumentation in biology

    Energy Technology Data Exchange (ETDEWEB)

    Gasperini, F. M. [Medical Science Program, Fluminense Federal Univ., Niteroi (Brazil); Pereira, G. R. [Dept. of Metallurgical and Materials Engineering, Federal Univ. of Rio de Janeiro (Brazil); Granjeiro, J. M. [Molecular and Cell Biology Dept., Fluminense Federal Univ., Niteroi, Rio de Janeiro (Brazil); Calasans-Maia, M. D. [Oral Surgery Dept., Fluminense Federal Univ., Niteroi, Rio de Janeiro (Brazil); Rossi, A. M. [Biomaterials Laboratory, Brazilian Center of Physics Research, Rio de Janeiro (Brazil); Perez, C. A. [Brazilian Synchrotron Laboratory, Campinas, Sao Paulo (Brazil); Lopes, R. T.; Lima, I. [Nuclear Engineering Laboratory, Federal Univ. of Rio de Janeiro (Brazil)

    2011-07-01

    X-ray micro-fluorescence imaging technique has been used as a significant tool in order to investigate minerals contents in some kinds of materials. The aim of this study was to evaluate the elemental distribution of calcium and zinc in bone substitute materials (nano-hydroxyapatite spheres) and cortical bones through X-Ray Micro-fluorescence analysis with the increment of Synchrotron Radiation in order to evaluate the characteristics of the newly formed bone and its interface, the preexisting bone and biomaterials by the arrangement of collagen fibers and its birefringence. The elemental mapping was carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo, Brazil working at D09-XRF beam line. Based on this study, the results suggest that hydroxyapatite-based biomaterials are biocompatible, promote osteo-conduction and favored bone repair. (authors)

  7. New synchrotron powder diffraction facility for long-duration experiments.

    Science.gov (United States)

    Murray, Claire A; Potter, Jonathan; Day, Sarah J; Baker, Annabelle R; Thompson, Stephen P; Kelly, Jon; Morris, Christopher G; Yang, Sihai; Tang, Chiu C

    2017-02-01

    A new synchrotron X-ray powder diffraction instrument has been built and commissioned for long-duration experiments on beamline I11 at Diamond Light Source. The concept is unique, with design features to house multiple experiments running in parallel, in particular with specific stages for sample environments to study slow kinetic systems or processes. The instrument benefits from a high-brightness X-ray beam and a large area detector. Diffraction data from the commissioning work have shown that the objectives and criteria are met. Supported by two case studies, the results from months of measurements have demonstrated the viability of this large-scale instrument, which is the world's first dedicated facility for long-term studies (weeks to years) using synchrotron radiation.

  8. Synchrotron-based FTIR spectromicroscopy Cytotoxicity and heating considerations

    CERN Document Server

    Holman, H Y N; McKinney, W R

    2002-01-01

    Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectromicroscopy is a newly emerging bioanalytical and imaging tool. This unique technique provides mid-infrared (IR) spectra, hence chemical information, with high signal-to-noise at spatial resolutions as fine as 3 to 10 microns. Thus it enables researchers to locate, identify, and track specific chemical events within an individual living mammalian cell. Mid-IR photons are too low in energy (0.05 - 0.5 eV) to either break bonds or to cause ionization. In this review, we show that the synchrotron IR beam has no detectable effects on the short- and long-term viability, reproductive integrity, cell-cycle progression, and mitochondrial metabolism in living human cells, and produces only minimal sample heating (< 0.5 degrees C). These studies have established an important foundation for SR-FTIR spectromicroscopy in biological and biomedical research.

  9. 1994 activity report: Stanford Synchrotron Radiation Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Cantwell, K.; Dunn, L. [eds.

    1994-01-01

    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.

  10. New Pulsed Orbit Bump Magnets for the Fermilab Booster Synchrotron

    CERN Document Server

    Lackey, James; John, Carson; Kashikhin, Vladimir; Makarov, Alexander; Prebys, Eric

    2005-01-01

    The beam from the Fermilab Linac is injected onto a bump in the closed orbit of the Booster Synchrotron where a carbon foil strips the electrons from the Linac’s negative ion hydrogen beam. Although the Booster itself runs at 15Hz, heat dissipation in the orbit bump magnets has been one limitation to the fraction of the cycles that can be used for beam. New, 0.28T pulsed window frame dipole magnets have been constructed that will fit into the same space as the old ones, run at the full repetition rate of the Booster, and provide a larger bump to allow a cleaner injection orbit. The new magnets use a high saturation flux density Ni-Zn ferrite in the yoke rather than laminated steel. The presented magnetic design includes two and three dimensional magnetic field calculations with eddy currents and ferrite nonlinear effects.

  11. On-line control of the nonlinear dynamics for synchrotrons

    Science.gov (United States)

    Bengtsson, J.; Martin, I. P. S.; Rowland, J. H.; Bartolini, R.

    2015-07-01

    We propose a simple approach to the on-line control of the nonlinear dynamics in storage rings, based on compensation of the nonlinear resonance driving terms using beam losses as the main indicator of the strength of a resonance. The correction scheme is built on the analysis of the resonance driving terms in first perturbative order and on the possibility of using independent power supplies in the sextupole magnets, which is nowadays present in many synchrotron light sources. Such freedom allows the definition of "smart sextupole knobs" attacking each resonance separately. The compensation scheme has been tested at the Diamond light source and proved to be effective in opening up the betatron tune space, resonance free, available to the electron beam and to improve the beam lifetime.

  12. Spectrum Analyzer Application for the Proton Synchrotron Wall Current Monitors

    CERN Document Server

    Limpens, Rik

    The Proton Synchrotron (PS) is a key component in CERN's accelerator complex, where it usually accelerates either protons or heavy ions. The new acquisition system for the PS ring wall current monitors has been installed to be able to perform higher frequency measurements of a beam bunch. This is an important improvement, since the oscillating signals are related to losses of a beam bunch. The main goal of this project is to develop a LabVIEW application running on a Real-Time target to perform continuous and triggered spectral acquisition of a PS beam bunch and to provide a data visualization and analysis tool for the operators and users of the machine.

  13. Versatile AFM setup combined with micro-focused X-ray beam

    CERN Document Server

    Slobodskyy, T; Tholapi, R; Liefeith, L; Fester, M; Sprung, M; Hansen, W

    2015-01-01

    Micro-focused X-ray beams produced by third generation synchrotron sources offer new perspective of studying strains and processes at nanoscale. Atomic force microscope setup combined with a micro-focused synchrotron beam allows precise positioning and nanomanipulation of nanostructures under illumination. In this paper, we report on integration of a portable commercial atomic force microscope setup into a hard X-ray synchrotron beamline. Details of design, sample alignment procedure and performance of the setup are presented.

  14. Scaling behavior of circular colliders dominated by synchrotron radiation

    Science.gov (United States)

    Talman, Richard

    2015-08-01

    The scaling formulas in this paper — many of which involve approximation — apply primarily to electron colliders like CEPC or FCC-ee. The more abstract “radiation dominated” phrase in the title is intended to encourage use of the formulas — though admittedly less precisely — to proton colliders like SPPC, for which synchrotron radiation begins to dominate the design in spite of the large proton mass. Optimizing a facility having an electron-positron Higgs factory, followed decades later by a p, p collider in the same tunnel, is a formidable task. The CEPC design study constitutes an initial “constrained parameter” collider design. Here the constrained parameters include tunnel circumference, cell lengths, phase advance per cell, etc. This approach is valuable, if the constrained parameters are self-consistent and close to optimal. Jumping directly to detailed design makes it possible to develop reliable, objective cost estimates on a rapid time scale. A scaling law formulation is intended to contribute to a “ground-up” stage in the design of future circular colliders. In this more abstract approach, scaling formulas can be used to investigate ways in which the design can be better optimized. Equally important, by solving the lattice matching equations in closed form, as contrasted with running computer programs such as MAD, one can obtain better intuition concerning the fundamental parametric dependencies. The ground-up approach is made especially appropriate by the seemingly impossible task of simultaneous optimization of tunnel circumference for both electrons and protons. The fact that both colliders will be radiation dominated actually simplifies the simultaneous optimization task. All GeV scale electron accelerators are “synchrotron radiation dominated”, meaning that all beam distributions evolve within a fraction of a second to an equilibrium state in which “heating” due to radiation fluctuations is canceled by the “cooling” in

  15. Strong-Strong Beam-Beam Simulation of Bunch Length Splitting at the LHC

    CERN Document Server

    Qiang, J; Pieloni, Tatiana; Ohmi, Kazuhito

    2015-01-01

    Longitudinal bunch length splitting was observed for some LHC beams. In this paper, we will report on the study of the observation using strong-strong beam-beam simulations. We explore a variety of factors including initial momentum deviation, collision crossing angle, synchrotron tune, chromaticity, working points and bunch intensity that contribute to the beam particle loss and the bunch length splitting, and try to understand the underlying mechanism of the observed phenomena.

  16. Analytical estimation of ATF beam halo distribution

    Science.gov (United States)

    Wang, Dou; Philip, Bambade; Kaoru, Yokoya; Gao, Jie

    2014-12-01

    In order to study the backgrounds in the ATF2 beam line and the interaction point (IP), this paper has developed an analytical method to give an estimation of the ATF beam halo distribution based on K. Hirata and K. Yokoya's theory. The equilibrium particle distribution of the beam tail in the ATF damping ring is presented, with each electron affected by several stochastic processes such as beam-gas scattering, beam-gas bremsstrahlung and intra-beam scattering, in addition to the synchrotron radiation damping effects. This is a general method which can also be applied to other electron rings.

  17. Analytical estimation of ATF beam halo distribution

    CERN Document Server

    Wang, Dou; Yokoya, Kaoru; Gao, Jie

    2013-01-01

    In order to study the background status in the ATF2 beam line and the interaction point (IP), this paper developed an analytical method to give the estimation of ATF beam halo distribution based on K. Hirata and K. Yokoya's theory. The equilibrium particle distribution of beam tail in ATF damping ring, when each electron is being affected by, in addition to the synchrotron radiation damping effects, several stochastic processes, such as beam-gas scattring, beam-gas bremsstrahlung and intra-beam scattering, was presented. This method is common and can be applied on other electron rings.

  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. Dynamic intensity control system with RF-knockout slow-extraction in the HIMAC synchrotron

    Science.gov (United States)

    Sato, Shinji; Furukawa, Takuji; Noda, Koji

    2007-05-01

    We have developed a dynamic beam intensity control system intended for use in three-dimensional pencil-beam scanning irradiation. In this system, which controls the spill structure and intensities of the beams extracted from the synchrotron, the amplitude of the RF-knockout is controlled using a 10 kHz response. Its amplitude modulation function is generated based on an analytical one-dimensional model of the RF-knockout slow-extraction. Using feedback control of the proportional and integral controls, this system allows us to control the beam current dynamically in response to the request, as was experimentally verified in the HIMAC synchrotron. In this paper, we describe the system for controlling the amplitude modulation through the inclusion of feedback, and we provide some experimental results.

  20. Thermal management of next-generation contact-cooled synchrotron x-ray mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Khounsary, A.

    1999-10-29

    In the past decade, several third-generation synchrotrons x-ray sources have been constructed and commissioned around the world. Many of the major problems in the development and design of the optical components capable of handling the extremely high heat loads of the generated x-ray beams have been resolved. It is expected, however, that in the next few years even more powerful x-ray beams will be produced at these facilities, for example, by increasing the particle beam current. In this paper, the design of a next generation of synchrotron x-ray mirrors is discussed. The author shows that the design of contact-cooled mirrors capable of handing x-ray beam heat fluxes in excess of 500 W/mm{sup 2} - or more than three times the present level - is well within reach, and the limiting factor is the thermal stress rather then thermally induced slope error.

  1. Design Options of a High-power Synchrotron for Laguna-LBNO

    CERN Document Server

    Papaphilippou, Y; Alekou, A; Antoniou, F; Benedikt, M; Efthymiopoulos, I; Garoby, R; Gerigk, F; Goddard, B; Lazaridis, C; Parfenova, A; Shaposhnikova, E; Steerenberg, R

    2013-01-01

    Design studies have been initiated at CERN, exploring the prospects of future high-power proton beams for producing neutrinos, within the LAGUNA-LBNO project. These studies include the design of a 2 MW high-power proton synchrotron (HP-PS) using the LP-SPL as injector. This paper resumes the design options under study in order to reach this high power, and their implications regarding layout, magnet technology, beam loss control and RF considerations

  2. A dedicated synchrotron light source for ultrafast x-ray science

    Energy Technology Data Exchange (ETDEWEB)

    Corlett, J.; DeSantis, S.; Hartman, N.; Heimann, P.; Lafever, R.; Li, D.; Padmore, H.; Rimmer, R.; Robinson, K.E.; Schoenlein, R.; Tanabe, J.; Wang, S.; Zholents, A.; Kairan, D.

    2001-06-16

    We describe a proposed femtosecond synchrotron radiation x-ray source based on a flat-beam RF gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. X-ray pulse durations of <100 fs at a 10 kHz repetition rate are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression.

  3. A Furnace for Diffraction Studies using Synchrotron X-Ray Radiation

    DEFF Research Database (Denmark)

    Buras, B.; Lebech, Bente; Kofoed, W.

    1984-01-01

    A furnace for diffraction studies using synchrotron X-ray radiation is described. The furnace can be operated between ambient temperature and 1 800 °C with a temperature stability better than 5 °C for temperatures above 300 °C. Kapton windows allow almost 360° access for the X-ray beam in the hor...

  4. Synchrotron and Compton Components and their Variability in BL Lac Objects

    CERN Document Server

    Giommi, P; Padovani, P; Tagliaferri, G

    2000-01-01

    BL Lacertae objects are extreme extragalactic sources characterized by theemission of strong and rapidly variable nonthermal radiation over the entireelectromagnetic spectrum. Synchrotron emission followed by inverse Comptonscattering in a relativistic beaming scenario is generally thought to be themechanism powering these objects. ...

  5. Methods of computer processing of experimental data on the intensity of bunches in synchrotrons

    Science.gov (United States)

    Zhabitsky, V. M.

    2016-12-01

    Methods of computer processing of experimental data on the intensity of bunches in synchrotrons for the purpose of receiving functional dependences from time during the accelerating cycle for a number of circulating particles and the mean-square length of a bunch are discussed. Examples of such dependences for the beam at the nuclotron (JINR) and PSB (CERN) are presented.

  6. Rilke and Modem Chinese Poetry%里尔克与中国现代新诗

    Institute of Scientific and Technical Information of China (English)

    张岩泉

    2012-01-01

    里尔克是20世纪杰出的德语诗人,也是对中国现代新诗产生过重大影响的诗人。从20年代初到40年代末,中国诗人从"生疏"到"亲切"的译介过程,使里尔克在中国现代新诗史上刻下了窄而深的印记;冯至、九叶诗人学习借鉴里尔克的诗学观念、诗歌艺术与精神品格成效显著,尤其在静观物象、凝然沉思的写作中,奉献出一批新诗名篇。不过,对里尔克晚期作品与思想的有所忽略,则给中国新诗与外国诗歌的交流留下了历史缺憾,提出了新的课题。%As a distinguished 20th-century poet in the German language, Rainer Maria Rilke becomes a major influence on modern Chinese poetry. Through Chinese poets' and scholars' translation and introduction from the early 1920s till the late 1940s, Rilke and his works had left narrow but deep traces on the course of modem Chinese poetry. Feng Zhi and Jiuye poets had learnt a lot from Rilke' s poetic concepts, poetry skills and moral character, which led to a num- ber of their excellent modern poems by their watching in tranquility and writing in reflection. However, the long neglect of Rilke' s late works and ideas has left a gap in the history of poetic exchange between China and the Western world, which raises a new subject for us.

  7. Genome-wide transcription responses to synchrotron microbeam radiotherapy.

    Science.gov (United States)

    Sprung, Carl N; Yang, Yuqing; Forrester, Helen B; Li, Jason; Zaitseva, Marina; Cann, Leonie; Restall, Tina; Anderson, Robin L; Crosbie, Jeffrey C; Rogers, Peter A W

    2012-10-01

    The majority of cancer patients achieve benefit from radiotherapy. A significant limitation of radiotherapy is its relatively low therapeutic index, defined as the maximum radiation dose that causes acceptable normal tissue damage to the minimum dose required to achieve tumor control. Recently, a new radiotherapy modality using synchrotron-generated X-ray microbeam radiotherapy has been demonstrated in animal models to ablate tumors with concurrent sparing of normal tissue. Very little work has been undertaken into the cellular and molecular mechanisms that differentiate microbeam radiotherapy from broad beam. The purpose of this study was to investigate and compare the whole genome transcriptional response of in vivo microbeam radiotherapy versus broad beam irradiated tumors. We hypothesized that gene expression changes after microbeam radiotherapy are different from those seen after broad beam. We found that in EMT6.5 tumors at 4-48 h postirradiation, microbeam radiotherapy differentially regulates a number of genes, including major histocompatibility complex (MHC) class II antigen gene family members, and other immunity-related genes including Ciita, Ifng, Cxcl1, Cxcl9, Indo and Ubd when compared to broad beam. Our findings demonstrate molecular differences in the tumor response to microbeam versus broad beam irradiation and these differences provide insight into the underlying mechanisms of microbeam radiotherapy and broad beam.

  8. Performance of extraction kicker magnet in a rapid cycling synchrotron

    Science.gov (United States)

    Kamiya, Junichiro; Takayanagi, Tomohiro; Watanabe, Masao

    2009-07-01

    Installation of the kicker magnets in the extraction section of the rapid cycling synchrotron in the J-PARC facility has been completed. They succeeded in extracting the proton beam accelerated up to 3 GeV in the first commissioning with beam. The operation parameters of the kicker system agreed well with the parameters, which were estimated from the magnetic field measurement and the current test of each power supply. The distribution of the integrated magnetic field is flat enough to meet the beam requirements. The beam based measurement of the flattop of the magnetic field was performed with the beam position monitors. Although a ringing structure was observed, which exceeded the specified limit, the degree of the flattop distortion could be corrected by the timing adjustment of the output current. The stability of the power supply is on the order of ±0.2%, which is sufficient to achieve stable beam extraction. The rise time of the output current largely depends on the gas pressure in the thyratrons. Dependence of the rise time on the gas pressure was strictly measured and the number of unwanted prefires could be reduced.

  9. A critical experimental test of synchrotron radiation theory with 3rd generation light source

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-05-15

    A recent ''beam splitting'' experiment at LCLS apparently demonstrated that after a microbunched electron beam is kicked on a large angle compared to the divergence of the FEL radiation, the microbunching wave front is readjusted along the new direction of motion of the kicked beam. Therefore, coherent radiation from an undulator placed after the kicker is emitted along the kicked direction without suppression. This strong emission of coherent undulator radiation in the kicked direction cannot be explained in the framework of conventional synchrotron radiation theory. In a previous paper we explained this puzzle. We demonstrated that, in accelerator physics, the coupling of fields and particles is based, on the one hand, on the use of results from particle dynamics treated according to the absolute time convention and, on the other hand, on the use of Maxwell equations treated according to the standard (Einstein) synchronization convention. Here lies the misconception which led to the strong qualitative disagreement between theory and experiment. After the ''beam splitting'' experiment at LCLS, it became clear that the conventional theory of synchrotron radiation cannot ensure the correct description of coherent and spontaneous emission from a kicked electron beam, nor the emission from a beam with finite angular divergence, in an undulator or a bending magnet. However, this result requires further experimental confirmation. In this publication we propose an uncomplicated and inexpensive experiment to test synchrotron radiation theory at 3rd generation light sources.

  10. Producing Terahertz Conherent Synchrotron Radiation Based On Hefei Light Source

    CERN Document Server

    De-Rong, Xu; Yan, Shao

    2014-01-01

    This paper theoretically proves that an electron storage ring can generate coherent radiation in THz region using a quick kicker magnet and an ac sextupole magnet. When the vertical chromaticity is modulated by the ac sextupole magnet, the vertical beam collective motion excited by the kicker produces a wavy spatial structure after a number of longitudinal oscillation periods. We calculate the radiation spectral distribution from the wavy bunch in Hefei Light Source(HLS). If we reduce electron energy to 400MeV, it can produce extremely strong coherent synchrotron radiation(CSR) at 0.115THz.

  11. Synchrotron radiation backgrounds for the FCC-hh experiments

    CERN Document Server

    Collamati, Francesco; Burkhardt, Helmut; Kersevan, Roberto

    2017-01-01

    In this paper we present a detailed analysis of the Synchrotron Radiation emitted by the 50 TeV protons of the FCC-hh in the last bending and quadrupole magnets upstream of the interaction region. We discuss the characteristics of this radiation in terms of power, flux, photon spectrum and fans with and without crossing angle for comparison. We mainly focus our study on the fraction of photons that may hit the detector, with a full tracking in GEANT4 that simulates the interaction within the central beam pipe.

  12. Calculation of the characteristics of infrared synchrotron radiation

    CERN Document Server

    Maslova, M V; Maltsev, M A

    2005-01-01

    Subroutines for calculating the spectral and angular characteristics of infrared synchrotron radiation are developed. Corresponding calculations are carried out for a number of proton and electron accelerators. The results obtained enable methods to be developed for beam diagnostics as well as highly sensitive detectors of infrared radiation for remote contactless nondestructive diagnostics and for investigating bunches and high-speed processes in ring-type (CERN /SEPS-LHC) and linear (GSI bunch target) accelerators, and also the thermal fields in nuclear power plants.

  13. Automated tuning of the advanced photon source booster synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Biedron, S.G.; Milton, S.V.

    1997-08-01

    The acceleration cycle of the Advanced Photon Source (APS) booster synchrotron is completed within 223 ms and is repeated at 2 Hz. Unless properly corrected, transverse and longitudinal injection errors can lead to inefficient booster performance. In order to simplify daily operation, automated tuning methods have been developed. Through the use of beam position monitor (BPM) reading, transfer line corrector magnets, magnet ramp timing, and empirically determined response functions, the injection process is optimized by correcting the first turn trajectory to the measured closed orbit. These tuning algorithms and their implementation are described here along with an evaluation of their performance.

  14. Stanford Synchrotron Radiation Laboratory. Activity report for 1989

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    The April, 1990 SPEAR synchrotron radiation run was one of the two or three best in SSRL`s history. High currents were accumulated, ramping went easily, lifetimes were long, beam dumps were infrequent and the average current was 42.9 milliamps. In the one month of operation, 63 different experiments involving 208 scientists from 50 institutions received beam. The end-of-run summary forms completed by the experimenters indicated high levels of user satisfaction with the beam quality and with the outstanding support received from the SSRL technical and scientific staffs. These fine experimental conditions result largely from the SPEAR repairs and improvements performed during the past year and described in Section I. Also quite significant was Max Cornacchia`s leadership of the SLAG staff. SPEAR`s performance this past April stands in marked contrast to that of the January-March, 1989 run which is also described in Section I. It is, we hope, a harbinger of the operation which will be provided in FY `91, when the SPEAR injector project is completed and SPEAR is fully dedicated to synchrotron radiation research. Over the coming years, SSRL intends to give highest priority to increasing the effectiveness of SPEAR and its various beam lines. The beam line and facility improvements performed during 1989 are described in Section III. In order to concentrate effort on SSRL`s three highest priorities prior to the March-April run: (1) to have a successful run, (2) to complete and commission the injector, and (3) to prepare to operate, maintain and improve the SPEAR/injector system, SSRL was reorganized. In the new organization, all the technical staff is contained in three groups: Accelerator Research and Operations Division, Injector Project and Photon Research and Operations Division, as described in Section IV. In spite of the limited effectiveness of the January-March, 1989 run, SSRL`s users made significant scientific progress, as described in Section V of this report.

  15. Brightness of synchrotron radiation from wigglers

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca, E-mail: gianluca.geloni@xfel.eu [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2016-01-21

    According to the 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. We exemplify this formalism in simple limiting cases. We consider the problem of the calculation of the wiggler source size by means of numerical simulations alone, which play the same role of an experiment. We report a significant numerical disagreement between exact calculations and approximations currently used in the literature.

  16. Brightness of synchrotron radiation from wigglers

    Science.gov (United States)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2016-01-01

    According to the 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. We exemplify this formalism in simple limiting cases. We consider the problem of the calculation of the wiggler source size by means of numerical simulations alone, which play the same role of an experiment. We report a significant numerical disagreement between exact calculations and approximations currently used in the literature.

  17. 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...

  18. A Remote and Virtual Synchrotron Beamline

    Science.gov (United States)

    Jackson, J. M.; Alp, E.; Sturhahn, W.

    2012-12-01

    National facilities offer one-of-a-kind opportunities to apply state-of-the-art experimental techniques to the pressing scientific problems of today. Yet, few students are able to experience research projects at national facilities due to limited accessibility caused in part by limited involvement in the local academic institution, constrained working areas at the experimental stations, and/or travel costs. We present a virtual and remote beam-line for Earth science studies using nuclear resonant and inelastic x-ray scattering methods at Sector 3 of the Advanced Photon Source at Argonne National Laboratory. Off-site students have the capability of controlling their measurements via secure internet connections and webcams. Students can access a 'view only mode' for ease of interaction and safety-control. More experienced users have exclusive control of the experiment and can remotely change variables within the experimental setup. Students may also access the virtual aspects these experiments by simulating certain conditions with our newly developed software. We evaluate such a tool by giving "before" and "after" assignments to students at different levels. These levels include high-school students from the Pasadena and greater Los Angeles area school districts, undergraduate students from Caltech's SURF/MURF program, and graduate students at Caltech. We specifically target underrepresented groups. Our results thus far show that the capabilities offered by our remote and virtual beamline show improved knowledge and understanding of applying experimental-based studies at the synchrotron to solve problems in the Earth sciences.

  19. Beam-Beam Effect with an External Noise in LHC

    CERN Document Server

    Ohmi, K; Höfle, Wolfgang; Tomás, R; Zimmermann, F

    2007-01-01

    In absence of synchrotron radiation, proton beams do not have any damping mechanism for incoherent betatron motion. A noise, which kicks beam particles in the transverse plane, gives a coherent betatron amplitude. If the system is linear, the coherent motion is maintained in amplitude. Nonlinear force, beam-beam and beam-electron cloud interactions, cause a decoherence of the betatron motion keeping the amplitude of each beam particle, with the result that an emittance growth arises. We focus only on fast noise with a correlation time of 1-100 turns. Slower noise is less serious, because it is regarded as an adiabatic change like a closed orbit change. As sources of the noise, we consider the bunch by bunch feedback system and phase jitter of cavities which turns to transverse noise via a crab cavity.

  20. Resolving two beams in beam splitters with a beam position monitor

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S. (Sergey)

    2002-01-01

    The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters. Monitoring two separated beams in a common beam pipe in the splitter sections imposes certain requirements on diagnostics for these sections. In this note we explore a two-beam system in a generic beam monitor and study the feasibility of resolving the positions of the two beams with a single diagnostic device. In the Advanced Hydrotest Facility (AHF), 20-ns beam pulses (bunches) are extracted from the 50-GeV main proton synchrotron and then are transported to the target by an elaborated transport system. The beam transport system splits the beam bunches into equal parts in its splitting sections so that up to 12 synchronous beam pulses can be delivered to the target for the multi-axis proton radiography. Information about the transverse positions of the beams in the splitters, and possibly the bunch longitudinal profile, should be delivered by some diagnostic devices. Possible candidates are the circular wall current monitors in the circular pipes connecting the splitter elements, or the conventional stripline BPMs. In any case, we need some estimates on how well the transverse positions of the two beams can be resolved by these monitors.

  1. Photoelectron photoion molecular beam spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Trevor, D.J.

    1980-12-01

    The use of supersonic molecular beams in photoionization mass spectroscopy and photoelectron spectroscopy to assist in the understanding of photoexcitation in the vacuum ultraviolet is described. Rotational relaxation and condensation due to supersonic expansion were shown to offer new possibilities for molecular photoionization studies. Molecular beam photoionization mass spectroscopy has been extended above 21 eV photon energy by the use of Stanford Synchrotron Radiation Laboratory (SSRL) facilities. Design considerations are discussed that have advanced the state-of-the-art in high resolution vuv photoelectron spectroscopy. To extend gas-phase studies to 160 eV photon energy, a windowless vuv-xuv beam line design is proposed.

  2. Use of a Synchrotron Radiation X-Ray Microprobe for Elemental Analysis at the National Synchrotron Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, B. M.

    1980-04-01

    The National Synchrotron Light Source (NSLS) is a facility consisting of a 700 MeV and a 2.5 GeV electron storage ring and dedicated to providing synchrotron radiation in the energy range from the vacuum ultraviolet to high energy x rays. Some of the properties of synchrotron radiation that contribute to its usefulness for x-ray fluorescence are: a continuous, tunable energy spectrum, strong collimation in the horizontal plane, high polarization in the storage ring plane, and relatively low energy deposition. The highest priority is for the development of an x-ray microprobe beam line capable of trace analysis in the parts per million range with spatial resolution as low as one micrometer. An eventual capability for bulk sample analysis is also planned with sensitivities in the more favorable cases being as low as 50 parts per billion in dry biological tissue. The microprobe technique has application to a variety of fields including the geological, medical, materials and environmental sciences. Examples of investigations include multielemental trace analysis across grain boundaries for the study of diffusion and cooling processes in geological and materials sciences samples; in leukocytes and other types of individual cells for studying the relationship between trace element concentrations and disease or nutrition; and in individual particles in air pollution samples.

  3. 现代舞之"力"的探讨%Study on the Force of Modem Dance

    Institute of Scientific and Technical Information of China (English)

    李超

    2011-01-01

    This essay expounds the modem dance art developing in western nations from 20th century from the “force”.From four levels discussed the theory about force of world famous artists, dancers: “force to the dance” put forward by Susan Lange who is the famous America artist, the father of western modern dance named Rudolf Von Laban tried to reveal the dance “force” with the theory of “force effect”, one of the three art giants in 20th century named Marsha Graham was going about to explore the force in dance, and Doris Humphrey who is the founder of American modern dance attempt to reveal the dance force.Eventually, the author draws the conclusion that the modern dance is the most pure way to express the human nature and life experience which resort to human body.%文章从"力"的角度阐释了20世纪开始西方世界如火如荼发展的现代舞艺术,分四个层次论述了世界著名的艺术家、舞蹈家有关力的学说:美国著名符号学家苏珊-朗格对舞蹈的力的认识,西方现代舞之父冯·鲁道夫·拉班通过创立"力效理论"揭示了舞蹈的"力"的奥秘,20世纪三大艺术巨匠之一、美国现代舞奠基人玛莎·格雷姆有关"力"的探索和另一位美国现代舞蹈奠基人多丽丝·韩芙莉对舞蹈"力"的揭示.文章通过分析最终得出了结论:现代舞是以最纯粹的生命状态--"力"的方式将隐秘的人性、生命的体验诉诸于人体并加以呈现的.

  4. CCD sensors in synchrotron X-ray detectors

    Science.gov (United States)

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

    1988-04-01

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

  5. Sensitive beam current measurement for FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Schwickert, Marcus; Kurian, Febin; Reeg, Hansjoerg [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Seidel, Paul; Neubert, Ralf [Friedrich-Schiller-Universitaet Jena (Germany); Geithner, Rene; Vodel, Wolfgang [Helmholtz-Institut Jena (Germany)

    2012-07-01

    Presently FAIR, the Facility for Antiproton and Ion Research, entered the final planning phase at GSI. The new accelerator facility requires precise devices for beam current measurements due to the large dynamics in beam intensities for the various synchrotrons, transport lines and storage rings. We report on the actual developments of beam diagnostic devices for the measurement of beam intensities ranging from 5 x 10{sup 11} uranium ions down to the detection of less than 10{sup 4} antiprotons. This contribution gives an overview of the planned instruments with a focus on non-intercepting beam current transformers, and summarizes the on-going development of a cryogenic current comparator.

  6. Modeling Longitudinal Dynamics in the Fermilab Booster Synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Ostiguy, Jean-Francois [Fermilab; Bhat, Chandra [Fermilab; Lebedev, Valeri [Fermilab

    2016-06-01

    The PIP-II project will replace the existing 400 MeV linac with a new, CW-capable, 800 MeV superconducting one. With respect to current operations, a 50% increase in beam intensity in the rapid cycling Booster synchrotron is expected. Booster batches are combined in the Recycler ring; this process limits the allowed longitudinal emittance of the extracted Booster beam. To suppress eddy currents, the Booster has no beam pipe; magnets are evacuated, exposing the beam to core laminations and this has a substantial impact on the longitudinal impedance. Noticeable longitudinal emittance growth is already observed at transition crossing. Operation at higher intensity will likely necessitate mitigation measures. We describe systematic efforts to construct a predictive model for current operating conditions. A longitudinal only code including a laminated wall impedance model, space charge effects, and feedback loops is developed. Parameter validation is performed using detailed measurements of relevant beam, rf and control parameters. An attempt is made to benchmark the code at operationally favorable machine settings.

  7. Brightness of synchrotron radiation from undulators and bending magnets

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-15

    We consider the maximum of the Wigner distribution (WD) of synchrotron radiation (SR) fields as a possible definition of SR source brightness. Such figure of merit was originally introduced in the SR community by Kim. The brightness defined in this way is always positive and, in the geometrical optics limit, can be interpreted as maximum density of photon flux in phase space. For undulator and bending magnet radiation from a single electron, the WD function can be explicitly calculated. In the case of an electron beam with a finite emittance the brightness is given by the maximum of the convolution of a single electron WD function and the probability distribution of the electrons in phase space. In the particular case when both electron beam size and electron beam divergence dominate over the diffraction size and the diffraction angle, one can use a geometrical optics approach. However, there are intermediate regimes when only the electron beam size or the electron beam divergence dominate. In this asymptotic cases the geometrical optics approach is still applicable, and the brightness definition used here yields back once more the maximum photon flux density in phase space. In these intermediate regimes we find a significant numerical disagreement between exact calculations and the approximation for undulator brightness currently used in literature. We extend the WD formalism to a satisfactory theory for the brightness of a bending magnet. We find that in the intermediate regimes the usually accepted approximation for bending magnet brightness turns out to be inconsistent even parametrically.

  8. The RF Cycle of the PIMMS Medical Synchrotron

    CERN Document Server

    Crescenti, M; Knaus, P

    2000-01-01

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

  9. Space-Charge Experiments at the CERN Proton Synchrotron

    CERN Document Server

    Franchetti, Giuliano; Hofmann, I; Martini, M; Métral, E; Qiang, J; Ryne, D; Steerenberg, R; CFA Beam Dynamics Workshop “High Intensity and Brightness Hadron Beams”

    2005-01-01

    Benchmarking of the simulation codes used for the design of the next generation of high beam power accelerators is of paramount importance due to the very demanding requirements on the level of beam losses. This is usually accomplished by comparing simulation results against available theories, and more importantly, against experimental observations. To this aim, a number of well-defined test cases, obtained by accurate measurements made in existing machines, are of great interest. Such measurements have been made in the CERN Proton Synchrotron to probe three space-charge effects: (i) transverse emittance blow-up due to space-charge induced crossing of the integer or half-integer stop-band, (ii) space-charge and octupole driven resonance trapping, and (iii) intensity-dependent emittance transfer between the two transverse planes. The last mechanism is discussed in detail in this paper and compared to simulation predictions.

  10. Evaluation of RBC aggregation using synchrotron X-ray speckles

    Science.gov (United States)

    Ha, Hojin; Nam, Kwon-Ho; Lee, Sang Joon

    2010-11-01

    When a coherent beam illuminates spatially-disordered particles, speckles are usually generated by the inference of the scattered light waves. The speckle has been known to contain the information of the objects under near-field condition. In this study, we hypothesized that the speckle patterns of the red blood cells are related to the aggregation shape and the size of RBCs in the medium. The speckle patterns of RBCs in static condition were investigated by transmitting the monochromatic synchrotron X-ray beam to the sample with varying hematocrit(10-80 %) and medium type(phosphate buffered saline, autologous plasma and 0.75 % polyvinylpyrrolidone 360 in phosphate buffered saline). The temporal variation of speckle patterns after sudden removal of shear rate was observed by stopping the blood flow in a tube. The size of aggregated RBCs is closely correlated with the characteristic features of the speckle patterns.

  11. Measurement and Compensation of Betatron Resonances at the CERN PS Booster Synchrotron

    CERN Document Server

    Urschütz, Peter; Benedikt, Michael

    2004-01-01

    The CERN PS Booster synchrotron is the first circular accelerator in the proton injector chain of the future Large Hadron Collider and links the linear accelerator, Linac2, with the Proton Synchrotron. Apart from serving as a pre-injector for the LHC, the PS Booster provides high intensity beams for the ISOLDE physics facility and various other beams for the Proton Synchrotron and its users. The 50 MeV proton beam coming from Linac2 is accumulated in the PS Booster by means of a multi-turn-injection scheme. Throughout injection, rf-capture and early acceleration, the individual particles in the beam “see” large, fluctuating incoherent space-charge tune shifts, consequently sweeping a large area in the tune diagram and covering many resonances. Thus, the beam suffers amplitude blow-up from transverse betatron resonances and an efficient compensation is required to avoid subsequent particle losses. The presently used resonance compensation scheme was established 25 years ago by orthogonal search of coupled ...

  12. Vacuum and magnetic field constraints in a H -/light ion synchrotron

    Science.gov (United States)

    Arduini, G.; Martin, R. L.; Rossi, S.; Silari, M.

    1994-08-01

    Acceleration of H - ions in a synchrotron imposes severe restrictions on the level of residual pressure in the vacuum chamber and the maximum magnetic field in the magnets of the ring. Significant vacuum requirements are also imposed by the acceleration of ions. This paper discusses these two aspects of the design of a combined H -/light ion synchrotron for radiation therapy. The fractional loss of the accelerated beam induced by the two processes is evaluated on the basis of a general treatment of the physics of these phenomena. The values of the vacuum and magnetic field necessary for normal operation of the machine are specified and a discussion is given of the behaviour of the above quantities as a function of several parameters such as beam energy, composition and pressure of the residual gas in the vacuum chamber and beam extraction time.

  13. Synchrotron infrared spectromicroscopy as a novel bioanalytical microprobe for individual living cells: Cytotoxicity considerations

    Energy Technology Data Exchange (ETDEWEB)

    Holman, Hoi-Ying N.; Bjornstad, Kathleen A.; McNamara, Morgan P.; Martin, Michael C.; McKinney, Wayne R.; Blakely, Eleanor A.

    2001-12-12

    Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectromicroscopy is a newly emerging analytical tool capable of monitoring the biochemistry within an individual living mammalian cell in real time. This unique technique provides infrared (IR)spectra, hence chemical information, with high signal-to-noise at spatial resolutions as fine as 3 to 10 microns. Mid-IR photons are too low in energy (0.05-0.5 eV) to either break bonds or to cause ionization, and the synchrotron IR beam has been shown to produce minimal sample heating. However, an important question remains, ''Does the intense synchrotron beam induce any cytotoxic effects in living cells?'' In this work, we present the results from a series of standard biological assays to evaluate any short-and/or long-term effects on cells exposed to the synchrotron radiation-based infrared (SR-IR) beam. Cell viability was tested using alcian blue dye-exclusion and colony formation assays. Cell-cycle progression was tested with bromodeoxyuridine (BrdU) uptake during DNA synthesis. Cell metabolism was tested using an 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. All control, 5-, 10-, and 20-minute SR-IR exposure tests (267 total and over 1000 controls) show no evidence of cytotoxic effects. Concurrent infrared spectra obtained with each experiment confirm no detectable chemistry changes between control and exposed cells.

  14. Extended one-dimensional method for coherent synchrotron radiation including shielding

    Directory of Open Access Journals (Sweden)

    David Sagan

    2009-04-01

    Full Text Available Coherent synchrotron radiation can severely limit the performance of accelerators designed for high brightness and short bunch length. Examples include light sources based on energy recovery LINAC or free-electron lasers, and bunch compressors for linear colliders. In order to better simulate coherent synchrotron radiation, a one-dimensional formalism due to Saldin, Schneidmiller, and Yurkov has been implemented in the general beam dynamics code Bmad. Wide vacuum chambers are simulated by means of vertical image charges. Results from Bmad are here compared to analytical approximations, to numerical solutions of the Maxwell equations, and to the simulation code elegant and the code of Agoh and Yokoya.

  15. Extended one-dimensional method for coherent synchrotron radiation including shielding

    Science.gov (United States)

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

    2009-04-01

    Coherent synchrotron radiation can severely limit the performance of accelerators designed for high brightness and short bunch length. Examples include light sources based on energy recovery LINAC or free-electron lasers, and bunch compressors for linear colliders. In order to better simulate coherent synchrotron radiation, a one-dimensional formalism due to Saldin, Schneidmiller, and Yurkov has been implemented in the general beam dynamics code Bmad. Wide vacuum chambers are simulated by means of vertical image charges. Results from Bmad are here compared to analytical approximations, to numerical solutions of the Maxwell equations, and to the simulation code elegant and the code of Agoh and Yokoya.

  16. Experimental Studies on Coherent Synchrotron Radiation at an Emittance Exchange Beamline

    Energy Technology Data Exchange (ETDEWEB)

    Thangaraj, J.C.T.; Thurman-Keup, R.; Ruan, J.; Johnson, A.S.; Lumpkin, A.H.; Santucci, J.; /Fermilab

    2012-04-01

    One of the goals of the Fermilab A0 photoinjector is to experimentally investigate the transverse to longitudinal emittance exchange (EEX) principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR) in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy chirped beam.

  17. 10μm thin transmissive photodiode produced by ALBA Synchrotron and IMB-CNM-CSIC

    Science.gov (United States)

    Cruz, C.; Jover-Manas, G.; Matilla, O.; Avila, J.; Juanhuix, J.; Pellegrini, G.; Quirion, D.; Rodriguez, J.

    2015-03-01

    Thin silicon photodiodes are common X-ray beam diagnosis devices at synchrotron facilities. Here we present a new device featuring an extremely thin layer that allows X-ray transmission over 90% for energies above 10 keV. The diode has a radiation-hard silicon junction with silicon dioxide passivation and a protective entrance window. These outstanding features make this device suited for diagnostic applications in X-ray synchrotron beamlines. Hereby preliminary results of X-ray transmission, responsivity and uniformity are presented.

  18. Study of silicon pixel sensor for synchrotron radiation detection

    Science.gov (United States)

    Li, Zhen-Jie; Jia, Yun-Cong; Hu, Ling-Fei; Liu, Peng; Yin, Hua-Xiang

    2016-03-01

    The silicon pixel sensor (SPS) is one of the key components of hybrid pixel single-photon-counting detectors for synchrotron radiation X-ray detection (SRD). In this paper, the design, fabrication, and characterization of SPSs for single beam X-ray photon detection is reported. The designed pixel sensor is a p+-in-n structure with guard-ring structures operated in full-depletion mode and is fabricated on 4-inch, N type, 320 μm thick, high-resistivity silicon wafers by a general Si planar process. To achieve high energy resolution of X-rays and obtain low dark current and high breakdown voltage as well as appropriate depletion voltage of the SPS, a series of technical optimizations of device structure and fabrication process are explored. With optimized device structure and fabrication process, excellent SPS characteristics with dark current of 2 nA/cm2, full depletion voltage 150 V are achieved. The fabricated SPSs are wire bonded to ASIC circuits and tested for the performance of X-ray response to the 1W2B synchrotron beam line of the Beijing Synchrotron Radiation Facility. The measured S-curves for SRD demonstrate a high discrimination for different energy X-rays. The extracted energy resolution is high (10 keV) and the linear properties between input photo energy and the equivalent generator amplitude are well established. It confirmed that the fabricated SPSs have a good energy linearity and high count rate with the optimized technologies. The technology is expected to have a promising application in the development of a large scale SRD system for the Beijing Advanced Photon Source. Supported by Prefabrication Research of Beijing Advanced Photon Source (R&D for BAPS) and National Natural Science Foundation of China (11335010)

  19. Discussing the processes constraining the Jovian synchrotron radio emission's features

    Science.gov (United States)

    Santos-Costa, Daniel; Bolton, Scott J.

    2008-03-01

    Our recent analysis and understanding of the Jovian synchrotron radio emission with a radiation-belt model is presented. In this work, the electron population is determined by solving the Fokker-Planck diffusion equation and considering different physical processes. The results of the modeling are first compared to in situ particle data, brightness distributions, radio spectrum, and beaming curves to verify the simulated particle distributions. The dynamics of high-energy electrons in Jupiter's inner magnetosphere and their related radio emission are then examined. The results demonstrate that the Jovian moons set the extension and intensity of the synchrotron emission's brightness distribution along the magnetic equator. Simulations show that moons and dust both control the transport toward the planet by significantly reducing the abundance of particles constrained to populate, near the equator and inside 1.8 Jovian radii, the innermost region of the magnetosphere. Due to interactions with dust and synchrotron mechanism, radiation-belt electrons are moved along field lines, between Metis (1.79 Jovian radii) and Amalthea (2.54 Jovian radii), toward high latitudes. The quantity of particles transported away from the equator is sufficient to produce measurable secondary radio emissions. Among all the phenomena acting in the inner magnetosphere, the moons (Amalthea and Thebe) are the primary moderator for the radiation's intensity at high latitudes. Moon losses also affect the characteristics of the total radio flux with longitude. The sweeping effect amplifies the 10-h modulation of the beaming curve's amplitude while energy resonances occurring near Amalthea and Thebe belong to phenomena adjusting it to the right level. Interactions with dust do not significantly constrain radio spectrum features. Resonances near Amalthea and Thebe are responsible for the Jovian radio spectrum's particular slope.

  20. High resolution 3D imaging of synchrotron generated microbeams

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, Frank M., E-mail: frank.gagliardi@wbrc.org.au [Alfred Health Radiation Oncology, The Alfred, Melbourne, Victoria 3004, Australia and School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia); Cornelius, Iwan [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2500 (Australia); Blencowe, Anton [Division of Health Sciences, School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, South Australia 5000, Australia and Division of Information Technology, Engineering and the Environment, Mawson Institute, University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Franich, Rick D. [School of Applied Sciences and Health Innovations Research Institute, RMIT University, Melbourne, Victoria 3000 (Australia); Geso, Moshi [School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia)

    2015-12-15

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

  1. Stanford Synchrotron Radiation Laboratory activity report for 1986

    Energy Technology Data Exchange (ETDEWEB)

    Cantwell, K. [ed.

    1987-12-31

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

  2. Synchrotron-driven spallation sources

    CERN Document Server

    Bryant, P J

    1996-01-01

    The use of synchrotrons for pulsed neutron spallation sources is an example of scientific and technological spin-off from the accelerator development for particle physics. Accelerator-driven sources provide an alternative to the continuous-flux, nuclear reactors that currently furnish the majority of neutrons for research and development. Although the present demand for neutrons can be adequately met by the existing reactors, this situation is unlikely to continue due to the increasing severity of safety regulations and the declared policies of many countries to close down their reactors within the next decade or so. Since the demand for neutrons as a research tool is, in any case,expected to grow, there has been a corresponding interest in sources that are synchrotron-driven or linac-driven with a pulse compression ring and currently several design studies are being made. These accelerator-driven sources also have the advantage of a time structure with a high peak neutron flux. The basic requirement is for a...

  3. Sirepo for Synchrotron Radiation Workshop

    Energy Technology Data Exchange (ETDEWEB)

    2016-10-25

    Sirepo is an open source framework for cloud computing. The graphical user interface (GUI) for Sirepo, also known as the client, executes in any HTML5 compliant web browser on any computing platform, including tablets. The client is built in JavaScript, making use of the following open source libraries: Bootstrap, which is fundamental for cross-platform web applications; AngularJS, which provides a model–view–controller (MVC) architecture and GUI components; and D3.js, which provides interactive plots and data-driven transformations. The Sirepo server is built on the following Python technologies: Flask, which is a lightweight framework for web development; Jinja, which is a secure and widely used templating language; and Werkzeug, a utility library that is compliant with the WSGI standard. We use Nginx as the HTTP server and proxy, which provides a scalable event-driven architecture. The physics codes supported by Sirepo execute inside a Docker container. One of the codes supported by Sirepo is the Synchrotron Radiation Workshop (SRW). SRW computes synchrotron radiation from relativistic electrons in arbitrary magnetic fields and propagates the radiation wavefronts through optical beamlines. SRW is open source and is primarily supported by Dr. Oleg Chubar of NSLS-II at Brookhaven National Laboratory.

  4. On intrinsic nonlinear particle motion in compact synchrotrons

    Science.gov (United States)

    Hwang, Kyung Ryun

    Due to the low energy and small curvature characteristics of compact synchrotrons, there can be unexpected features that were not present or negligible in high energy accelerators. Nonlinear kinetics, fringe field effect, and space charge effect are those features which become important for low energy and small curvature accelerators. Nonlinear kinematics can limit the dynamics aperture for compact machine even if it consists of all linear elements. The contribution of the nonlinear kinematics on nonlinear optics parameters are first derived. As the dipole bending radius become smaller, the dipole fringe field effect become stronger. Calculation of the Lie map generator and corresponding mapping equation of dipole fringe field is presented. It is found that the higher order nonlinear potential is inverse proportional to powers of fringe field extent and correction to focusing and low order nonlinear potential is proportional to powers of fringe field extent. The fringe field also found to cause large closed orbit deviation for compact synchrotrons. The 2:1 and 4:1 space charge resonances are known to cause beam loss, emittance growth and halo formation for low energy high intensity beams. By numerical simulations, we observe a higher order 6:2 space charge resonance, which can successfully be understood by the concatenation of 2:1 and 4:1 resonances via canonical perturbation. We also develop an explicit symplectic tracking method for compact electrostatic storage rings and explore the feasibility of electric dipole moment (EDM) measurements.

  5. Electron Beam Dynamics in 4GLS

    CERN Document Server

    Williams, P H; Muratori, B D; Owen, H L; Smith, S L

    2007-01-01

    Studies of the electron beam dynamics for the 4GLS design are presented. 4GLS will provide three different electron bunch trains to a variety of user synchrotron sources. The 1 kHz XUV-FEL and 100 mA High Average Current branches share a common 540 MeV linac, whilst the 13 MHz IR-FEL must be well-synchronised to them. An overview of the injector designs, electron transport, and energy recovery is given, including ongoing studies of coherent synchrotron radiation, beam break-up and wakefields. This work is being pursued for the forthcoming Technical Design Report due in 2008.

  6. Considerations for NSLS-II Synchrotron Radiation Protection When Operating Damping Wigglers at Low Machine Energy

    Energy Technology Data Exchange (ETDEWEB)

    Seletskiy, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Dept.; Podobedov, B. [Brookhaven National Lab. (BNL), Upton, NY (United States). Photon Sciences Dept.

    2015-12-30

    The NSLS-II storage ring vacuum chamber, including frontends (FE) and beamlines (BL), is protected from possible damage from synchrotron radiation (SR) emitted from insertion devices (IDs) by a dedicated active interlock system (AIS). The system monitors electron beam position and angle and triggers a beam dump if the beam orbit is outside of the active interlock envelope (AIE). The AIE was calculated under the assumptions of 3 GeV beam energy and ID gaps set to their minimum operating values (i.e. “fully closed”). Recently it was proposed to perform machine studies that would ramp the stored beam energy significantly below the nominal operational value of 3 GeV. These studies may potentially include the use of NSLS-II damping wigglers (DWs) for electron beam emittance reduction and control.

  7. Study of the Charge Density Control Method Including the Space Charge Effect in the Proton Synchrotron

    Science.gov (United States)

    Kato, Shinichi; Harada, Hiroyuki; Hotchi, Hideaki; Okabe, Kota; Yamamoto, Kazami; Kinsho, Michikazu

    For high intensity proton accelerators, one of the beam loss sources is the incoherent tune spread caused by the space charge force. In the 3 GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, beams are injected sequentially and shifted slightly from the central orbit in order to increase the beam size intentionally and suppress the charge density and incoherent tune spread. This injection method has been adopted and suppressed the beam loss. However, simulations clarified that beams did not spread as much as expected because of the space charge effect in the high current case. As simulation results of the optimized beam shift pattern when the space charge effect is considered, it was obtained that the incoherent tune spread could be suppressed to an extent that has not been achieved previously.

  8. Experimental study of coherent synchrotron radiation in the emittance exchange line at the A0-photoinjector

    CERN Document Server

    Thangaraj, Jayakar C T; Johnson, A; Lumpkin, A H; Edwards, H; Ruan, J; Santucci, J; Sun, Y E -; Church, M; Piot, P

    2012-01-01

    Next generation accelerators will require a high current, low emittance beam with a low energy spread. Such accelerators will employ advanced beam conditioning systems such as emittance exchangers to manipulate high brightness beams. One of the goals of the Fermilab A0 photoinjector is to investigate the transverse to longitudinal emittance exchange principle. Coherent synchrotron radiation could limit high current operation of the emittance exchanger. In this paper, we report on the preliminary experimental and simulation study of the coherent synchroton radiation (CSR) in the emittance exchange line at the A0 photoinjector.

  9. Longitudinal bunch monitoring at the Fermilab Tevatron and Main Injector synchrotrons

    CERN Document Server

    Thurman-Keup, R; Blokland, W; Crisp, J; Eddy, N; Fellenz, B; Flora, R; Hahn, A; Hansen, S; Kiper, T; Para, A; Pordes, S; Tollestrup, A V

    2011-01-01

    The measurement of the longitudinal behavior of the accelerated particle beams at Fermilab is crucial to the optimization and control of the beam and the maximizing of the integrated luminosity for the particle physics experiments. Longitudinal measurements in the Tevatron and Main Injector synchrotrons are based on the analysis of signals from resistive wall current monitors. This article describes the signal processing performed by a 2 GHz-bandwidth oscilloscope together with a computer running a LabVIEW program which calculates the longitudinal beam parameters.

  10. 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).

  11. Synchrotron applications in wood preservation and deterioration

    Science.gov (United States)

    Barbara L. Illman

    2003-01-01

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

  12. Synchrotron radiation absorber for high density loads

    Science.gov (United States)

    Anashin, V. V.; Kuzminych, V. S.; Trakhtenberg, E. M.; Zholents, A. A.

    1991-10-01

    A design of a special synchrotron radiation absorber for the storage ring VEPP-4M is presented. The density of the synchrotron radiation power on the absorber surface is up to 500 W/mm 2. The absorber is made from a beryllium plate, brazed inside to the copper vacuum chamber, which is intensively water-cooled from outside.

  13. 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.

  14. 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.

  15. A new method for beam stacking in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, C.M.; /Fermilab

    2008-06-01

    Recently, I developed a new beam stacking scheme for synchrotron storage rings called 'longitudinal phase-space coating' (LPSC). This scheme has been convincingly validated by multi-particle beam dynamics simulations and has been demonstrated with beam experiments at the Fermilab Recycler. Here, I present the results from both simulations and experiments. The beam stacking scheme presented here is the first of its kind.

  16. Effects of synchrotron radiation spectrum energy on polymethyl methacrylate photosensitivity to deep x-ray lithography

    CERN Document Server

    Mekaru, H; Hattori, T

    2003-01-01

    Since X-ray lithography requires a high photon flux to achieve deep resist exposure, a synchrotron radiation beam, which is not monochromatized, is generally used as a light source. If the synchrotron radiation beam is monochromatized, photon flux will decrease rapidly. Because of this reason, the wavelength dependence of the resist sensitivity has not been investigated for deep X-ray lithography. Measuring the spectrum of a white beam with a Si solid-state detector (SSD) is difficult because a white beam has a high intensity and an SSD has a high sensitivity. We were able to measure the spectrum and the photocurrent of a white beam from a beam line used for deep X-ray lithography by keeping the ring current below 0.05 mA. We evaluated the characteristics of the output beam based on the measured spectrum and photocurrent, and used them to investigate the relationship between the total exposure energy and the dose-processing depth with polymethyl methacrylate (PMMA). We found that it is possible to guess the p...

  17. Monte Carlo simulations of ultra high vacuum and synchrotron radiation for particle accelerators

    CERN Document Server

    AUTHOR|(CDS)2082330; Leonid, Rivkin

    With preparation of Hi-Lumi LHC fully underway, and the FCC machines under study, accelerators will reach unprecedented energies and along with it very large amount of synchrotron radiation (SR). This will desorb photoelectrons and molecules from accelerator walls, which contribute to electron cloud buildup and increase the residual pressure - both effects reducing the beam lifetime. In current accelerators these two effects are among the principal limiting factors, therefore precise calculation of synchrotron radiation and pressure properties are very important, desirably in the early design phase. This PhD project shows the modernization and a major upgrade of two codes, Molflow and Synrad, originally written by R. Kersevan in the 1990s, which are based on the test-particle Monte Carlo method and allow ultra-high vacuum and synchrotron radiation calculations. The new versions contain new physics, and are built as an all-in-one package - available to the public. Existing vacuum calculation methods are overvi...

  18. Contrast mechanism in superscrew dislocation images on synchrotron back-reflection topographs

    Energy Technology Data Exchange (ETDEWEB)

    Huang, X.R.; Dudley, M.; Vetter, W.M.; Huang, W.; Wang, S. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Materials Science and Engineering; Carter, C.H. Jr. [Cree Research, Inc., Durham, NC (United States)

    1998-12-31

    The topographic contrast of superscrew dislocations in 6H{single_bond}SiC crystals has been studied by synchrotron white-beam x-ray topography in the Bragg reflection geometry. The diffraction images of these dislocations are simulated using a ray-tracing method. Systematical simulations, which coincide with the dislocation images taken by back- and grazing-reflection topography, clearly reveal the kinematic diffraction mechanisms of the superscrew dislocation, and illustrate that synchrotron reflection topography is capable of providing accurate descriptions of the strain fields, the Burgers vector magnitudes, and the senses of these dislocations. In addition, the experiments and simulations demonstrate straightforwardly the relation between the topographic contrast and the lattice distortions, and therefore the general mechanisms underlying contrast formation of defect images in synchrotron reflection topographs are provided.

  19. The three-dimensional microstructure of polycrystalline materials unravelled by synchrotron light

    DEFF Research Database (Denmark)

    Ludwig, W.; King, A.; Herbig, M.

    2011-01-01

    The three-dimensional microstructure of polycrystalline materials unravelled by synchrotron light Synchrotron radiation X-ray imaging and diffraction techniques offer new possibilities for non-destructive bulk characterization of polycrystalline materials. Minute changes in electron density...... (different crystallographic phases, cracks, porosities) can be detected using 3D imaging modes exploiting Fresnel diffraction and the coherence properties of third generation synchrotron beams. X-ray diffraction contrast tomography, a technique based on Bragg diffraction imaging, provides access to the 3D...... shape, orientation and elastic strain state of the individual grains from polycrystalline sample volumes containing several hundred up to a few thousand grains. Combining both imaging modalities allows a comprehensive description of the microstructure of the material at the micrometer length scale...

  20. Stanford Synchrotron Radiation Laboratory 1991 activity report. Facility developments January 1991--March 1992

    Energy Technology Data Exchange (ETDEWEB)

    Cantwell, K.; St. Pierre, M. [eds.

    1992-12-31

    SSRL is a national facility supported primarily by the Department of Energy for the utilization of synchrotron radiation for basic and applied research in the natural sciences and engineering. It is a user-oriented facility which welcomes proposals for experiments from all researchers. The synchrotron radiation is produced by the 3.5 GeV storage ring, SPEAR, located at the Stanford Linear Accelerator Center (SLAC). SPEAR is a fully dedicated synchrotron radiation facility which operates for user experiments 7 to 9 months per year. SSRL currently has 24 experimental stations on the SPEAR storage ring. There are 145 active proposals for experimental work from 81 institutions involving approximately 500 scientists. There is normally no charge for use of beam time by experimenters. This report summarizes the activity at SSRL for the period January 1, 1991 to December 31, 1991 for research. Facility development through March 1992 is included.

  1. An introduction to beam physics

    CERN Document Server

    Berz, Martin; Wan, Weishi

    2015-01-01

    The field of beam physics touches many areas of physics, engineering, and the sciences. In general terms, beams describe ensembles of particles with initial conditions similar enough to be treated together as a group so that the motion is a weakly nonlinear perturbation of a chosen reference particle. Particle beams are used in a variety of areas, ranging from electron microscopes, particle spectrometers, medical radiation facilities, powerful light sources, and astrophysics to large synchrotrons and storage rings such as the LHC at CERN. An Introduction to Beam Physics is based on lectures given at Michigan State University’s Department of Physics and Astronomy, the online VUBeam program, the U.S. Particle Accelerator School, the CERN Academic Training Programme, and various other venues. It is accessible to beginning graduate and upper-division undergraduate students in physics, mathematics, and engineering. The book begins with a historical overview of methods for generating and accelerating beams, high...

  2. Application of Synchrotron Radiation in the Geological and Environmental Sciences

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Keith W.

    1999-09-01

    A survey of some of the different ways that synchrotrons x-ray beams can be used to study geological materials is presented here. This field developed over a period of about 30 years, and it is clear that the geological community has made major use of the many synchrotrons facilities operating around the world during this time period. This was a time of rapid change in the operational performance of the synchrotrons facilities and this in itself has made it possible for geologists to develop new and more refined types of experiments that have yielded many important results. The advance in experimental techniques has proceeded in parallel with a revolution in computing techniques that has made it possible to cope with the great amount of data accumulated in the experiments. It is reasonable, although risky, to speculate about what might be expected to develop in the field during the next five- to ten-year period. It does seem plausible that the rate of change in the performance of what might now be called conventional x-ray storage rings will slow. There are no new facilities that are superior to the ESRF, ALS, APS, or SPring8 facilities under construction or about to come into operation. Thus, performance increments in the characteristics of the x-ray sources may come through the introduction of specialized devices in existing storage rings. The free electron laser is one example of a developing new technology that should take us into new regions of performance for radiation sources and stimulate new types of experimental applications. It is also likely that major advances will come through the introduction of more sophisticated experimental devices developed for use with the very recently operational undulator or wiggler sources at the newer rings. Improved x-ray optics and x-ray detectors and more powerful computation and high-speed data transmission can bring about more refined experiments and make the synchrotrons facilities more widely available to the

  3. X-ray phase-contrast tomography with a compact laser-driven synchrotron source.

    Science.gov (United States)

    Eggl, Elena; Schleede, Simone; Bech, Martin; Achterhold, Klaus; Loewen, Roderick; Ruth, Ronald D; Pfeiffer, Franz

    2015-05-05

    Between X-ray tubes and large-scale synchrotron sources, a large gap in performance exists with respect to the monochromaticity and brilliance of the X-ray beam. However, due to their size and cost, large-scale synchrotrons are not available for more routine applications in small and medium-sized academic or industrial laboratories. This gap could be closed by laser-driven compact synchrotron light sources (CLS), which use an infrared (IR) laser cavity in combination with a small electron storage ring. Hard X-rays are produced through the process of inverse Compton scattering upon the intersection of the electron bunch with the focused laser beam. The produced X-ray beam is intrinsically monochromatic and highly collimated. This makes a CLS well-suited for applications of more advanced--and more challenging--X-ray imaging approaches, such as X-ray multimodal tomography. Here we present, to our knowledge, the first results of a first successful demonstration experiment in which a monochromatic X-ray beam from a CLS was used for multimodal, i.e., phase-, dark-field, and attenuation-contrast, X-ray tomography. We show results from a fluid phantom with different liquids and a biomedical application example in the form of a multimodal CT scan of a small animal (mouse, ex vivo). The results highlight particularly that quantitative multimodal CT has become feasible with laser-driven CLS, and that the results outperform more conventional approaches.

  4. Mobile setup for synchrotron based in situ characterization during thermal and plasma-enhanced atomic layer deposition

    Science.gov (United States)

    Dendooven, Jolien; Solano, Eduardo; Minjauw, Matthias M.; Van de Kerckhove, Kevin; Coati, Alessandro; Fonda, Emiliano; Portale, Giuseppe; Garreau, Yves; Detavernier, Christophe

    2016-11-01

    We report the design of a mobile setup for synchrotron based in situ studies during atomic layer processing. The system was designed to facilitate in situ grazing incidence small angle x-ray scattering (GISAXS), x-ray fluorescence (XRF), and x-ray absorption spectroscopy measurements at synchrotron facilities. The setup consists of a compact high vacuum pump-type reactor for atomic layer deposition (ALD). The presence of a remote radio frequency plasma source enables in situ experiments during both thermal as well as plasma-enhanced ALD. The system has been successfully installed at different beam line end stations at the European Synchrotron Radiation Facility and SOLEIL synchrotrons. Examples are discussed of in situ GISAXS and XRF measurements during thermal and plasma-enhanced ALD growth of ruthenium from RuO4 (ToRuS™, Air Liquide) and H2 or H2 plasma, providing insights in the nucleation behavior of these processes.

  5. The Beam Diagnostics for SESAME

    CERN Document Server

    Varnasseri, S

    2005-01-01

    SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is an Independent Intergovernmental Organization developed and officially established under the auspices of UNESCO. SESAME will become a major international research center in the Middle East, located in Allan, Jordan. The machine design is based on a 2.5 GeV 3rd generation Light Source with an emittance of 26 nm*rad and 12 straights for insertion devices. The conceptual design of the accelerator complex has been frozen and the engineering design is started. The completion of the accelerators complex construction is scheduled for the end of 2009. In the following an overview of the electron beam diagnostic system is presented, with special emphasis on the beam position monitoring system and the synchrotron light monitor.

  6. Stanford Synchrotron Radiation Laboratory. Activity report for 1988

    Energy Technology Data Exchange (ETDEWEB)

    Cantwell, K. [ed.

    1996-01-01

    For SSRL operations, 1988 was a year of stark contrasts. The first extended PEP parasitic running since the construction of our two beam lines on that storage ring took place in November and December. Four experiments discussed below, were performed and detailed operational procedures which allowed synchrotron radiation an high energy users to coexist were established. SSRL anticipates that there will be significant amounts of beam time when PEP is run again for high energy physics. On the other hand, activity on SPEAR consisted of brief parasitic running on the VUV lines in December when the ring was operated at 1.85 GeV for colliding beam experiments. There was no dedicated SPEAR running throughout the entire calendar year. This is the first time since dedicated SPEAR operation was initiated in 1980 that there was no such running. The decision was motivated by both cost and performance factors, as discussed in Section 1 of this report. Fortunately, SLAC and SSRL have reached an agreement on SPEAR and PEP dedicated time charges which eliminates the cost volatility which was so important in the cancellation of the June-July dedicated SPEAR run. As discussed in Section 2, the 3 GeV SPEAR injector construction is proceeding on budget and on schedule. The injector will overcome the difficulties associated with the SLC-era constraint of only two injections per day. SSR and SLAC have also embarked on a program to upgrade SPEAR to achieve high reliability and performance. As a consequence, SSRL`s users may anticipate a highly effective SPEAR by 1991, at the latest. At that time, SPEAR is expected to be fully dedicated to synchrotron radiation research and operated by SSRL. Also contained in this report is a discussion of the improvements to SSRL`s experimental facilities and highlights of the experiments of the past year.

  7. Simulation of Head-on Beam-Beam Limitations in Future High Energy Colliders

    CERN Document Server

    Buffat, Xavier; Florio, Adrien; Pieloni, Tatiana; Tambasco, Claudia

    2016-01-01

    The Future Circular Hadron Collider (FCC-hh) project calls for studies in a new regime of beam-beam interactions. While the emittance damping due to synchrotron radiation is still slower than in past or existing lepton colliders, it is significantly larger than in other hadron colliders. The slow reduction of the emittance is profitable for higher luminosity in term of transverse beam size at the interaction points and also to mitigate long-range beam-beam effects, potentially allowing for a reduction of the crossing angle between the beams during the operation. In such conditions, the strength of head-on beam-beam interactions increases, potentially limiting the beam brightness. 4D weak-strong and strong-strong simulations are performed in order to assess these limitations.

  8. Experimental demonstration of the induction synchrotron.

    Science.gov (United States)

    Takayama, Ken; Arakida, Yoshio; Dixit, Tanuja; Iwashita, Taiki; Kono, Tadaaki; Nakamura, Eiji; Otsuka, Kazunori; Shimosaki, Yoshito; Torikai, Kota; Wake, Masayoshi

    2007-02-01

    We report an experimental demonstration of the induction synchrotron, the concept of which has been proposed as a future accelerator for the second generation of neutrino factory or hadron collider. The induction synchrotron supports a superbunch and a superbunch permits more charge to be accelerated while observing the constraints of the transverse space-charge limit. 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.

  9. Beam Loss Monitors at the ESRF

    CERN Document Server

    Joly, B; Naylor, G A

    2000-01-01

    The European Synchrotron radiation facility is a third generation x-ray source providing x-rays on a continuous basis. As a facility available to external users, the monitoring of radiation caused by the loss of high-energy stored beam is of great concern. A network of beam loss monitors has been installed inside the storage ring tunnel so as to detect and localize the slow loss of electrons during a beam decay. This diagnostic tool allows optimization of beam parameters and physical aperture limits as well as giving useful information on the machine to allow the lifetime to be optimized and defects localized.

  10. One cryogenic collimator, tested with beam

    CERN Document Server

    EuCARD, Collaboration

    2014-01-01

    The main accelerator SIS100 of the FAIR-complex will provide heavy ion beams of highest intensities. Beam loss due to ionization is the most demanding loss mechanism at operation with high intensity, intermediate charge state heavy ions. A special synchrotron design has been developed for SIS100, aiming for hundred percent control of ionization beam loss by means of a dedicated cryogenic ion catcher system. To suppress dynamic vacuum effects, the cryocatcher system shall provide a significantly reduced effective desorption yield. The construction and test of a prototype cryocatcher is a task of the EuCARD WP8 ColMat. A prototype test setup, including cryostat has been constructed, manufactured and tested under realistic conditions with beams from the heavy ion synchrotron SIS18. The design and results are presented.

  11. High purity 100 GeV electron identification with synchrotron radiation arXiv

    CERN Document Server

    Depero, E.; Burtsev, V.; Chumakov, A.; Cooke, D.; Dermenev, A.V.; Donskov, S.V.; Dubinin, F.; Dusaev, R.R.; Emmenegger, S.; Fabich, A.; Frolov, V.N.; Gardikiotis, A.; Gninenko, S.N.; Hösgen, M.; Karneyeu, A.E.; Ketzer, B.; Kirsanov, M.M.; Konorov, I.V.; Kramarenko, V.A.; Kuleshov, S.V.; Lyubovitskij, V.E.; Lysan, V.; Matveev, V.A.; Mikhailov, Yu.V.; Myalkovskiy, V.V.; Peshekhonov, V.D.; Peshekhonov, D.V.; Polyakov, V.A.; Radics, B.; Rubbia, A.; Samoylenko, V.D.; Tikhomirov, V.O.; Tlisov, D.A.; Toropin, A.N.; Vasilishin, B.; Vasquez Arenas, G.; Ulloa, P.; Crivelli, P.

    In high energy experiments such as active beam dump searches for rare decays and missing energy events, the beam purity is a crucial parameter. In this paper we present a technique to reject heavy charged particle contamination in the 100 GeV electron beam of the H4 beam line at CERN SPS. The method is based on the detection with BGO scintillators of the synchrotron radiation emitted by the electrons passing through a bending dipole magnet. A 100 GeV $\\pi^-$ beam is used to test the method in the NA64 experiment resulting in a suppression factor of $10^{-5}$ while the efficiency for electron detection is $\\sim$95%. The spectra and the rejection factors are in very good agreement with the Monte Carlo simulation. The reported suppression factors are significantly better than previously achieved.

  12. High purity 100 GeV electron identification with synchrotron radiation

    Science.gov (United States)

    Depero, E.; Banerjee, D.; Burtsev, V.; Chumakov, A.; Cooke, D.; Dermenev, A. V.; Donskov, S. V.; Dubinin, F.; Dusaev, R. R.; Emmenegger, S.; Fabich, A.; Frolov, V. N.; Gardikiotis, A.; Gninenko, S. N.; Hösgen, M.; Karneyeu, A. E.; Ketzer, B.; Kirsanov, M. M.; Konorov, I. V.; Kramarenko, V. A.; Kuleshov, S. V.; Lyubovitskij, V. E.; Lysan, V.; Matveev, V. A.; Mikhailov, Yu. V.; Myalkovskiy, V. V.; Peshekhonov, V. D.; Peshekhonov, D. V.; Polyakov, V. A.; Radics, B.; Rubbia, A.; Samoylenko, V. D.; Tikhomirov, V. O.; Tlisov, D. A.; Toropin, A. N.; Vasilishin, B.; Arenas, G. Vasquez; Ulloa, P.; Crivelli, P.

    2017-09-01

    In high energy experiments such as active beam dump searches for rare decays and missing energy events, the beam purity is a crucial parameter. In this paper we present a technique to reject heavy charged particle contamination in the 100 GeV electron beam of the H4 beam line at CERN SPS. The method is based on the detection with BGO scintillators of the synchrotron radiation emitted by the electrons passing through a bending dipole magnet. A 100 GeV π- beam is used to test the method in the NA64 experiment resulting in a suppression factor of 10-5 while the efficiency for electron detection is ∼95%. The spectra and the rejection factors are in very good agreement with the Monte Carlo simulation. The reported suppression factors are significantly better than previously achieved.

  13. A bent Laue-Laue monochromator for a synchrotron-based computed tomography system

    CERN Document Server

    Ren, B; Chapman, L D; Ivanov, I; Wu, X Y; Zhong, Z; Huang, X

    1999-01-01

    We designed and tested a two-crystal bent Laue-Laue monochromator for wide, fan-shaped synchrotron X-ray beams for the program multiple energy computed tomography (MECT) at the National Synchrotron Light Source (NSLS). MECT employs monochromatic X-ray beams from the NSLS's X17B superconducting wiggler beamline for computed tomography (CT) with an improved image quality. MECT uses a fixed horizontal fan-shaped beam with the subject's apparatus rotating around a vertical axis. The new monochromator uses two Czochralski-grown Si crystals, 0.7 and 1.4 mm thick, respectively, and with thick ribs on their upper and lower ends. The crystals are bent cylindrically, with the axis of the cylinder parallel to the fan beam, using 4-rod benders with two fixed rods and two movable ones. The bent-crystal feature of the monochromator resolved the difficulties we had had with the flat Laue-Laue design previously used in MECT, which included (a) inadequate beam intensity, (b) excessive fluctuations in beam intensity, and (c) i...

  14. CSR Impedance for Non-Ultrarelativistic Beams

    Energy Technology Data Exchange (ETDEWEB)

    Li, Rui [Jefferson Lab., Newport News, VA (United States); Tsai, Cheng Y. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Jefferson Lab., Newport News, VA (United States)

    2015-09-01

    For the analysis of the coherent synchrotron radiation (CSR)-induced microbunching gain in the low energy regime, such as when a high-brightness electron beam is transported through a low-energy merger in an energy-recovery linac (ERL) design, it is necessary to extend the CSR impedance expression in the ultrarelativistic limit to the non-ultrarelativistic regime. This paper presents our analysis of CSR impedance for general beam energies.

  15. Quantitative X-ray microtomography with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Donath, T. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Materialforschung

    2007-07-01

    Synchrotron-radiation-based computed microtomography (SR{sub {mu}}CT) is an established method for the examination of volume structures. It allows to measure the x-ray attenuation coefficient of a specimen three-dimensionally with a spatial resolution of about one micrometer. In contrast to conventional x-ray sources (x-ray tubes), the unique properties of synchrotron radiation enable quantitative measurements that do not suffer from beam-hardening artifacts. During this work the capabilities for quantitative SR{sub {mu}}CT measurements have been further improved by enhancements that were made to the SR{sub {mu}}CT apparatus and to the reconstruction chain. For high-resolution SR{sub {mu}}CT an x-ray camera consisting of luminescent screen (x-ray phosphor), lens system, and CCD camera was used. A significant suppression of blur that is caused by reflections inside the luminescent screen could be achieved by application of an absorbing optical coating to the screen surface. It is shown that blur and ring artifacts in the tomographic reconstructions are thereby drastically reduced. Furthermore, a robust and objective method for the determination of the center of rotation in projection data (sinograms) is presented that achieves sub-pixel precision. By implementation of this method into the reconstruction chain, complete automation of the reconstruction process has been achieved. Examples of quantitative SR{sub {mu}}CT studies conducted at the Hamburger Synchrotronstrahlungslabor HASYLAB at the Deutsches Elektronen-Synchrotron DESY are presented and used for the demonstration of the achieved enhancements. (orig.)

  16. Optimization of the Multi-turn Injection Efficiency for Medical Synchrotron

    CERN Document Server

    Kim, J; Yoon, M

    2016-01-01

    We present a method for optimization of the multi-turn injection effciency for medical synchrotron. We show that for given injection energy the injection efficiency can be greatly enhanced by choosing transverse tunes appropriately as well as optimizing the injection bump and the number of turns required for beam injection. We verify our study by applying the method to the Korea Heavy Ion Medical Accelerator (KHIMA) synchrotron which is currently built at the campus of Dongnam Institute of Radiological and Medical Sciences (DIRAMS) in Busan, Korea. First the frequency map analysis is performed with the help of ELEGANT and ACCSIM codes. The tunes which yield the good injection efficiency are then selected. With these tunes the injection bump and the number of turns required for injection are then optimized by tracking a number of particles up to one thousand turns after injection beyond which there is no further beam loss. Results for optimization of the injection efficiency for proton ion are presented.

  17. Development of a new Frequency Program in the CERN Proton Synchrotron

    CERN Document Server

    Sundal, Magnus; Larsen, Ragnhild; Johnsen, Ragnar

    The development of a new frequency program in the Proton Synchrotron (PS) is a project that links existing and new infrastructure in the first particle accelerator built at CERN. In a particle synchrotron, the magnetic field strength of the bending magnets and the revolution frequency of the particles are coupled to keep a circulating beam at fixed orbit during acceleration. The frequency program delivers a revolution frequency based on the measurements of the bending magnets. Ongoing renovations in the magnet measurement system are changing the way the information is distributed from the magnets. Once implemented, it will represent a step towards fully digital beam controls. This project involves development of both Very High Speed Integrated Circuit Hardware Description Language (VHDL) firmware and Printed Circuit Boards (PCBs) in the form of FPGA Mezzanine Cards (FMCs) to adapt the frequency program to the new transmission protocol called White Rabbit. The White Rabbit is a network solution that provides s...

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

    Science.gov (United States)

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

    2015-06-01

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

  19. Synchrotron X-ray CT characterization of titanium parts fabricated by additive manufacturing. Part II. Defects.

    Science.gov (United States)

    Scarlett, Nicola Vivienne Yorke; Tyson, Peter; Fraser, Darren; Mayo, Sheridan; Maksimenko, Anton

    2016-07-01

    Synchrotron X-ray tomography (SXRT) has been applied to the study of defects within three-dimensional printed titanium parts. These parts were made using the Arcam EBM(®) (electron beam melting) process which uses powdered titanium alloy, Ti64 (Ti alloy with approximately 6%Al and 4%V) as the feed and an electron beam for the sintering/welding. The experiment was conducted on the Imaging and Medical Beamline of the Australian Synchrotron. The samples represent a selection of complex shapes with a variety of internal morphologies. Inspection via SXRT has revealed a number of defects which may not otherwise have been seen. The location and nature of such defects combined with detailed knowledge of the process conditions can contribute to understanding the interplay between design and manufacturing strategy. This fundamental understanding may subsequently be incorporated into process modelling, prediction of properties and the development of robust methodologies for the production of defect-free parts.

  20. 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.

  1. 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).

  2. Solenoid and Synchrotron radiation effects in CLIC

    CERN Document Server

    Dalena, B; Tomás, R; Angal-Kalinin, D

    2010-01-01

    The emission of Synchrotron Radiation in the CLIC BDS is one of the major limitations of the machine performance. An extensive revision of this phenomenon is presented with special emphasis on the Interaction point (IP) solenoid.

  3. Simulation of synchrotron motion with rf noise

    Energy Technology Data Exchange (ETDEWEB)

    Leemann, B.T.; Forest, E.; Chattopadhyay, S.

    1986-08-01

    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.

  4. Beam Time Accounting

    CERN Document Server

    Seitova, Diana

    2016-01-01

    ISOLDE is one of the leading research facilities in the field of nuclear physics. A proton beam with an energy 1.4 GeV coming from the Proton Synchrotron Booster (PSB) hits one of the targets at ISOLDE and produces Radioactive Ion Beams (RIBs). Then, the RIBs of interest is selected and delivered to the different experimental stations. In order to deliver the beam to the certain experimental station, the positions of the devices along the beamline should satisfy certain conditions. The purpose of this project is to define the conditions for the beam to pass through the different beamlines and to store the data about device’s status for later analysis and statistics, so it would be possible to know when the beam was used for different experiments. The data with the settings of the different devices is saved in the Timber database and the first steps for making virtual devices to compile the status of the beamlines were completed.

  5. Efficient Analytical Approaches to the Optics of Compound Refractive Lenses for Use with Synchrotron X-rays

    DEFF Research Database (Denmark)

    Poulsen, Stefan Othmar; Poulsen, Henning Friis

    2014-01-01

    The properties of compound refractive lenses (CRLs) of biconcave parabolic lenses for focusing and imaging synchrotron X-rays have been investigated theoretically by ray transfer matrix analysis and Gaussian beam propagation. We present approximate analytical expressions, that allow fast estimation...

  6. Precision Calibration of Infrared Synchrotron Radiation Detectors

    CERN Document Server

    Maltsev, A A; Maslova, M V

    2003-01-01

    The technique of calibration of synchrotron radiation precision detectors on a tungsten source based on similarity (close similarity) of character of spectral distributions of synchrotron and thermal radiations is given. The characteristics of various commonly used lamps, used as "standard" ones, are given. The errors of measurements are analyzed. The detectors are intended for absolute measurements of the number of electrons in a ring-shaped bunch.

  7. Wakefields in Coherent Synchrotron Radiation

    Science.gov (United States)

    Billinghurst, Brant E.; Bergstrom, J. C.; Baribeau, C.; Batten, T.; Dallin, L.; May, Tim E.; Vogt, J. M.; Wurtz, Ward A.; Warnock, Robert L.; Bizzozero, D. A.; Kramer, S.; Michaelian, K. H.

    2016-06-01

    When the electron bunches in a storage ring are sufficiently short the electrons act coherently producing radiation several orders of magnitude more intense than normal synchrotron radiation. This is referred to as Coherent Syncrotron Radiation (CSR). Due to the potential of CSR to provide a good source of Terahertz radiation for our users, the Canadian Light Source (CLS) has been researching the production and application of CSR. CSR has been produced at the CLS for many years, and has been used for a number of applications. However, resonances that permeate the spectrum at wavenumber intervals of 0.074 cm-1, and are highly stable under changes in the machine setup, have hampered some experiments. Analogous resonances were predicted long ago in an idealized theory. Through experiments and further calculations we elucidate the resonance and wakefield mechanisms in the CLS vacuum chamber. The wakefield is observed directly in the 30-110 GHz range by rf diodes. These results are consistent with observations made by the interferometer in the THz range. Also discussed will be some practical examples of the application of CSR for the study of condensed phase samples using both transmission and Photoacoustic techniques.

  8. Synchrotron radiation from massless charge

    CERN Document Server

    Gal'tsov, D V

    2015-01-01

    Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some general arguments suggest that strictly massless charge does not not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for {\\em ab initio} massless particle of zero spin. Provided $E^2\\gg eH$, the maximum in the spectrum is shown to be at $\\hbar \\omega=E/3$, and the average photon energy is $4E/9$. The normalized spectrum is universal, depending neither on $E$ nor on $H$. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Our results are consistent with the view (sup...

  9. Synchrotron radiation from massless charge

    Directory of Open Access Journals (Sweden)

    D.V. Gal'tsov

    2015-07-01

    Full Text Available Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some authors suggest that strictly massless charge does not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for ab initio massless particle of zero spin. Provided E2≫eH, the maximum in the spectrum is shown to be at ħω=E/3, and the average photon energy is 4E/9. The normalized spectrum is universal, depending neither on E nor on H. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Classical theory is reliable only as providing the low-frequency part of the true quantum radiation spectrum.

  10. A study on radiation shielding and safety analysis for a synchrotron radiation beamline

    Energy Technology Data Exchange (ETDEWEB)

    Asano, Yoshihiro [Japan Atomic Energy Research Inst., Kansai Research Establishment, Synchrotron Radiation Research Center, Mikazuhi, Hyogo (Japan)

    2001-03-01

    Methods of shielding design and safety analysis are presented for a beam-line of synchrotron radiation. This paper consists of the shielding and safety study of synchrotron radiation with extremely intense and low energy photon below several hundreds keV, and the study for the behavior of remarkable high-energy photons up to 8 GeV, which can creep into beam-lines. A new shielding design code, STAC8 was developed to estimate the leakage dose outside the beam line hutch (an enclosure of the beam, optical elements or experimental instruments) easily and quickly with satisfactory accuracy. The code can calculate consistently from sources of synchrotron radiation to dose equivalent outside hutches with considering the build up effect and polarization effect. Validity of the code was verified by comparing its calculations with those of Monte Carlo simulations and measurement results of the doses inside the hutch of the BL14C of Photon Factory in the High Energy Accelerator Research Organization (KEK), showing good agreements. The shielding design calculations using STAC8 were carried out to apply to the practical beam-lines with the considering polarization effect and clarified the characteristics of the typical beam-line of the third generation synchrotron radiation facility, SPring-8. In addition, the shielding calculations were compared with the measurement outside the shield wall of the bending magnet beam-line of SPring-8, and showed fairly good agreement. The new shielding problems, which have usually been neglected in shielding designs for existing synchrotron radiation facilities, are clarified through the analysis of the beam-line shielding of SPring-8. The synchrotron radiation from the SPring-8 has such extremely high-intensity involving high energy photons that the scattered synchrotron radiation from the concrete floor of the hutch, the ground shine, causes a seriously high dose. The method of effective shielding is presented. For the estimation of the gas

  11. Peak Satellite-to-Earth Data Rates Derived From Measurements of a 20 Gbps Bread-Board Modem

    Science.gov (United States)

    Landon, David G.; Simons, Rainee N.; Wintucky, Edwin G.; Sun, Jun Y.; Winn, James S.; Laraway, Stephen A.; McIntire, William K.; Metz, John L.; Smith, Francis J.

    2011-01-01

    A prototype data link using a Ka-band space qualified, high efficiency 200 W TWT amplifier and a bread-board modem emulator were created to explore the feasibility of very high speed communications in satellite-to-earth applications. Experiments were conducted using a DVB-S2-like waveform with modifications to support up to 20 Gbps through the addition of 128-Quadrature Amplitude Modulation (QAM). Limited by the bandwidth of the amplifier, a constant peak symbol rate of 3.2 Giga-symbols/sec was selected and the modulation order was varied to explore what peak data rate might be supported by an RF link through this amplifier. Using 128-QAM, an implementation loss of 3 dB was observed at 20 Gbps, and the loss decreased as data rate or bandwidth were reduced. Building on this measured data, realistic link budget calculations were completed. Low-Earth orbit (LEO) missions based on this TWTA with reasonable hardware assumptions and antenna sizing are found to be bandwidth-limited, rather than power-limited, making the spectral efficiency of 9/10-rate encoded 128-QAM very attractive. Assuming a bandwidth allocation of 1 GHz, these computations indicate that low-Earth orbit vehicles could achieve data rates up to 5 Gbps-an order of magnitude beyond the current state-of-practice, yet still within the processing power of a current FPGA-based software-defined modem. The measured performance results and a description of the experimental setup are presented to support these conclusions.

  12. Beam emittance reduction during operation of Indus-2

    Energy Technology Data Exchange (ETDEWEB)

    Fakhri, Ali Akbar, E-mail: fakhri@rrcat.gov.in; Kant, Pradeep; Ghodke, A. D.; Singh, Gurnam [Raja Ramanna Centre for Advanced Technology, Indore 452 013 (India)

    2015-11-15

    Indus-2 storage ring is a 2.5 GeV third generation synchrotron radiation source. This source was commissioned using a moderate optics. Beam injection was accomplished using an off momentum electron beam to avoid difficulties faced in storage of beam at 550 MeV. The injection procedure and relevant beam dynamical studies are discussed. The switch over from the moderate optics to low emittance optics is done at 2.5 GeV after storing the electron beam. The procedure evolved to reduce the beam emittance and its implementation during the operation is discussed.

  13. Characteristics of radiation safety for synchrotron radiation and X-ray free electron laser facilities.

    Science.gov (United States)

    Asano, Yoshihiro

    2011-07-01

    Radiation safety problems are discussed for typical electron accelerators, synchrotron radiation (SR) facilities and X-ray free electron laser (XFEL) facilities. The radiation sources at the beamline of the facilities are SR, including XFEL, gas bremsstrahlung and high-energy gamma ray and photo-neutrons due to electron beam loss. The radiation safety problems for each source are compared by using 8 GeV class SR and XFEL facilities as an example.

  14. National synchrotron light source. Annual report 1985, October 1, 1984-September 30, 1985

    Energy Technology Data Exchange (ETDEWEB)

    Thomlinson, W.; White-DePace, S. (eds.)

    1985-10-01

    The NSLS has made great strides in the past year. Both storage rings are now in full operational status. The users have assembled a most impressive array of beam lines and are making creative use of them. This report outlines the status, describes the facility, and discusses some of the science which is being produced. The facility represents not only a large increase in the national capacity to do synchrotron research, but a new level of capability, with further gains occurring rapidly.

  15. Comparing the effect of low and high emittance on synchrotron radiation and beamline design

    Directory of Open Access Journals (Sweden)

    A Gholampour Azhir

    2017-08-01

    Full Text Available In this paper, we have discussed about the role of two emittance values suggested for Iranian Light Source Facility (ILSF (3.278 and 0.476 nm.rad on different radiation features of the synchrotron light sources (bending magnet, shaker and oscillator such as spot size, divergence of the beam on light spot, brilliance and important quantities in beamline design such as photon cross-section, optical element sizes and energy resolution  

  16. Setup for measurements of partial ion yields at the Synchrotron Radiation Center

    Science.gov (United States)

    Wehlitz, R.; Lukić, D.; Koncz, C.; Sellin, I. A.

    2002-03-01

    A new setup for measuring partial photoion yields was developed and built at the Synchrotron Radiation Center. The vacuum chamber, which accommodates an ion time-of-flight spectrometer, a metal vapor oven, and a liquid nitrogen cooled trap, consists mainly of a standard conflat 6 in. six-way cross and a 6 in. tee. A differential pumping stage separates the vacuum chamber from the beam line. First experiments with this apparatus were performed using neon, lithium, and beryllium.

  17. Stanford Synchrotron Radiation Laboratory activity report for 1987

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, S.; Cantwell, K. [eds.

    1988-12-31

    During 1987, SSRL achieved many significant advances and reached several major milestones utilizing both SPEAR and PEP as synchrotron radiation sources as described in this report. Perhaps the following two are worthy of particular mention: (1) SPEAR reached an all time high of 4,190 delivered user-shifts during calendar year 1987, highlights of the many scientific results are given; (2) during a 12 day run in December of 1987, PEP was operated in a low emittance mode (calculated emittance 6.4 nanometer-radians) at 7.1 GeV with currents up to 33 mA. A second undulator beam line on PEP was commissioned during this run and used to record many spectra showing the extremely high brightness of the radiation. PEP is now by far the highest brightness synchrotron radiation source in the world. The report is divided into the following sections: (1) laboratory operations; (2) accelerator physics programs; (3) experimental facilities; (4) engineering division; (5) conferences and workshops; (6) SSRL organization; (7) experimental progress reports; (8) active proposals; (9) SSRL experiments and proposals by institution; and (10) SSRL publications.

  18. Synchrotron radiation shielding design and ICRP radiological protection quantities.

    Science.gov (United States)

    Bassey, Bassey; Moreno, Beatriz; Chapman, Dean

    2015-06-01

    Protection and operational quantities as defined by the International Commission on Radiological Protection (ICRP) and the International Commission on Radiation Units and Measurements (ICRU) are the two sets of quantities recommended for use in radiological protection for external radiation. Since the '80s, the protection quantities have evolved from the concept of dose equivalent to effective dose equivalent to effective dose, and the associated conversion coefficients have undergone changes. In this work, the influence of three different versions of ICRP photon dose conversion coefficients in the synchrotron radiation shielding calculations of an experimental enclosure has been examined. The versions are effective dose equivalent (ICRP Publication 51), effective dose (ICRP Publication 74), and effective dose (ICRP Publication 116) conversion coefficients. The sources of the synchrotron radiation white beam into the enclosure were a bending magnet, an undulator and a wiggler. The ranges of photons energy from these sources were 10-200 keV for the bending magnet and undulator, and 10-500 keV for the wiggler. The design criterion aimed a radiation leakage less than 0.5 µSv h(-1) from the enclosure. As expected, larger conversion coefficients in ICRP Publication 51 lead to higher calculated dose rates. However, the percentage differences among the calculated dose rates get smaller once shielding is added, and the choice of conversion coefficients set did not affect the final shielding decision.

  19. Phase contrast imaging of breast tumours with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Olivo, A. [Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT (United Kingdom)], E-mail: aolivo@medphys.ucl.ac.uk; Rigon, L. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Area Science Park, Padriciano 99, 34012 Trieste (Italy)], E-mail: rigon@ts.infn.it; Vinnicombe, S.J. [Department of Radiology, St. Bartholomews Hospital, Barts and the London NHS Trust, West Smithfield, London EC1A 7BE (United Kingdom)], E-mail: s.j.vinnicombe@qmul.ac.uk; Cheung, K.C. [STFC Daresbury Laboratory, Keckwick Lane, Warrington, Cheshire WA4 4AD (United Kingdom)], E-mail: k.c.cheung@dl.ac.uk; Ibison, M. [Department of Physics, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom)], E-mail: m.ibison@dl.ac.uk; Speller, R.D. [Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT (United Kingdom)], E-mail: rspeller@medphys.ucl.ac.uk

    2009-06-15

    Even though the potential of phase contrast (PC) imaging has been demonstrated in a number of biological tissue samples, the availability of free-space propagation phase contrast images of real breast tumours is still limited. The aim of this study was to obtain phase contrast images of two different pathological breast specimens containing tumours of differing morphological type at two synchrotron radiation (SR) facilities, and to assess any qualitative improvements in the evaluation and characterisation of the masses through the use of phase contrast imaging. A second aim was to assess the effects of parameters such as detector resolution, beam energy and sample-to-detector distance on image quality using the same breast specimens, as to date these effects have been modelled and discussed only for geometric phantoms. At each synchrotron radiation facility a range of images was acquired with different detectors and by varying the above parameters. Images of the same samples were also acquired with the absorption-based approach to allow a direct comparison and estimation of the advantages specifically ascribable to the PC technique.

  20. Cancellation of coherent synchrotron radiation kicks with optics balance.

    Science.gov (United States)

    Di Mitri, S; Cornacchia, M; Spampinati, S

    2013-01-04

    Minimizing transverse emittance is essential in linear accelerators designed to deliver very high brightness electron beams. Emission of coherent synchrotron radiation (CSR), as a contributing factor to emittance degradation, is an important phenomenon to this respect. A manner in which to cancel this perturbation by imposing certain symmetric conditions on the electron transport system has been suggested.We first expand on this idea by quantitatively relating the beam Courant-Snyder parameters to the emittance growth and by providing a general scheme of CSR suppression with asymmetric optics, provided it is properly balanced along the line. We present the first experimental evidence of this cancellation with the resultant optics balance of multiple CSR kicks: the transverse emittance of a 500 pC, sub-picosecond, high brightness electron beam is being preserved after the passage through the achromatic transfer line of the FERMI@Elettra free electron laser, and emittance growth is observed when the optics balance is intentionally broken. We finally show the agreement between the theoretical model and the experimental results. This study holds the promise of compact dispersive lines with relatively large bending angles, thus reducing costs for future electron facilities.

  1. 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 ...

  2. Nanofocusing optics for synchrotron radiation made from polycrystalline diamond.

    Science.gov (United States)

    Fox, O J L; Alianelli, L; Malik, A M; Pape, I; May, P W; Sawhney, K J S

    2014-04-07

    Diamond possesses many extreme properties that make it an ideal material for fabricating nanofocusing x-ray optics. Refractive lenses made from diamond are able to focus x-ray radiation with high efficiency but without compromising the brilliance of the beam. Electron-beam lithography and deep reactive-ion etching of silicon substrates have been used in a transfer-molding technique to fabricate diamond optics with vertical and smooth sidewalls. Latest generation compound refractive lenses have seen an improvement in the quality and uniformity of the optical structures, resulting in an increase in their focusing ability. Synchrotron beamline tests of two recent lens arrays, corresponding to two different diamond morphologies, are described. Focal line-widths down to 210 nm, using a nanocrystalline diamond lens array and a beam energy of E = 11 keV, and 230 nm, using a microcrystalline diamond lens at E = 15 keV, have been measured using the Diamond Light Source Ltd. B16 beamline. This focusing prowess is combined with relatively high transmission through the lenses compared with silicon refractive designs and other diffractive optics.

  3. Solving X-ray protein structures without a crystal: using X-ray Free Electron Laser, the fourth generation synchrotron light sources

    Institute of Scientific and Technical Information of China (English)

    Bo Huang

    2010-01-01

    @@ A synchrotron light source is a source of electromagnetic radiation artificially produced by specialized electron accelerators. Compared to the commonly used in-house X-ray sources, it is wavelength adjustable, much stronger and more focused. In the last two decades, synchrotron usage has become the mainstream for X-ray protein structure determination. Taking the advantage of micro-focus light beams of the third generation synchrotron, the size of a usable protein crystal for data collection decreases to micron level, which increases the rate of macromolecular structure determination to about 10 new protein data bank entries per day.

  4. Simulation of temperature distribution by finite element analysis on different components of the EXAFS beamline at INDUS-II synchrotron source

    Indian Academy of Sciences (India)

    D Bhattacharyya; S N Jha; N C Das; Vishnu Verma; S G Markandeya; A K Ghosh

    2005-12-01

    An extended X-ray absorption fine structure (EXAFS) beamline is being developed for the INDUS-II synchrotron source. Several optical and mechanical components of the beamline are exposed to high intensity synchrotron radiation while in operation. The temperature rise on different components of the beamline on exposure to the synchrotron beam has been simulated by finite element analysis. Design of the cooling mechanism for each of these components has been carried out and estimation of the temperature rise has also been done incorporating the cooling mechanism.

  5. The 57Fe Synchrotron Mössbauer Source at the ESRF.

    Science.gov (United States)

    Potapkin, Vasily; Chumakov, Aleksandr I; Smirnov, Gennadii V; Celse, Jean Philippe; Rüffer, Rudolf; McCammon, Catherine; Dubrovinsky, Leonid

    2012-07-01

    The design of a (57)Fe Synchrotron Mössbauer Source (SMS) for energy-domain Mössbauer spectroscopy using synchrotron radiation at the Nuclear Resonance beamline (ID18) at the European Synchrotron Radiation Facility is described. The SMS is based on a nuclear resonant monochromator employing pure nuclear reflections of an iron borate ((57)FeBO(3)) crystal. The source provides (57)Fe resonant radiation at 14.4 keV within a bandwidth of 15 neV which is tunable in energy over a range of about ±0.6 µeV. In contrast to radioactive sources, the beam of γ-radiation emitted by the SMS is almost fully resonant and fully polarized, has high brilliance and can be focused to a 10 µm × 5 µm spot size. Applications include, among others, the study of very small samples under extreme conditions, for example at ultrahigh pressure or combined high pressure and high temperature, and thin films under ultrahigh vacuum. The small cross section of the beam and its high intensity allow for rapid collection of Mössbauer data. For example, the measuring time of a spectrum for a sample in a diamond anvil cell at ∼100 GPa is around 10 min, whereas such an experiment with a radioactive point source would take more than one week and the data quality would be considerably less. The SMS is optimized for highest intensity and best energy resolution, which is achieved by collimation of the incident synchrotron radiation beam and thus illumination of the high-quality iron borate crystal within a narrow angular range around an optimal position of the rocking curve. The SMS is permanently located in an optics hutch and is operational immediately after moving it into the incident beam. The SMS is an in-line monochromator, i.e. the beam emitted by the SMS is directed almost exactly along the incident synchrotron radiation beam. Thus, the SMS can be easily utilized with all existing sample environments in the experimental hutches of the beamline. Owing to a very strong

  6. Brightness of synchrotron radiation from undulators and bending magnets.

    Science.gov (United States)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2015-03-01

    The maximum of the Wigner distribution (WD) of synchrotron radiation (SR) fields is considered as a possible definition of SR source brightness. Such a figure of merit was originally introduced in the SR community by Kim [(1986), Nucl. Instrum. Methods Phys. Res. A, 246, 71-76]. The brightness defined in this way is always positive and, in the geometrical optics limit, can be interpreted as the maximum density of photon flux in phase space. For undulator and bending magnet radiation from a single electron, the WD function can be explicitly calculated. In the case of an electron beam with a finite emittance the brightness is given by the maximum of the convolution of a single electron WD function and the probability distribution of the electrons in phase space. In the particular case when both electron beam size and electron beam divergence dominate over the diffraction size and the diffraction angle, one can use a geometrical optics approach. However, there are intermediate regimes when only the electron beam size or the electron beam divergence dominate. In these asymptotic cases the geometrical optics approach is still applicable, and the brightness definition used here yields back once more to the maximum photon flux density in phase space. In these intermediate regimes a significant numerical disagreement is found between exact calculations and the approximation for undulator brightness currently used in the literature. The WD formalism is extended to a satisfactory theory for the brightness of a bending magnet. It is found that in the intermediate regimes the usually accepted approximation for bending magnet brightness turns out to be inconsistent even parametrically.

  7. Control of the slow extraction process in a dedicated proton synchrotron for hadron therapy

    CERN Document Server

    Molodozhentsev, A Yu

    1999-01-01

    The ring design of the synchrotron for cancer treatment, based on the third-order resonant extraction, was been performed to meet the special medical requirements. The uniformity of the slow extracted beam from the proton synchrotron is the main requirement on the beam quality determined by the medical application. The smooth extraction during at least 400 msec should be realized for the `raster' scanning of tumours. Control of the slow extraction over the whole spill time is discussed in this report. To keep all lattice functions of the ring constant during the extraction a slow movement of the accelerated particles into the resonance can be used. To reduce degradation of the uniformity of the extracted beam by ripples from the power converters of the magnetic elements, the RF empty-bucket channeling method should be utilized. This method allows reduce the ripple influence during slow extraction. Both methods are analyzed to control the slow extraction for the dedicated proton synchrotron. The main parameter...

  8. Synchrotron radiation in strongly coupled conformal field theories

    CERN Document Server

    Athanasiou, Christiana; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna

    2010-01-01

    Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled ${\\cal N}=4$ supersymmetric Yang-Mills (SYM) theory. We compare the strong coupling results to those at weak coupling, finding them to be very similar. In both regimes, the angular distribution of the radiated power is in fact similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle $\\alpha \\sim 1/\\gamma$. To an observer far away from the quark, the emitted radiation appears as a short periodic burst, just like the light from a lighthouse does to a ship at sea. Our strong coupling results are valid for any strongly coupled conformal field theory with a dual classical gravity description.

  9. Measurement and analysis of coherent synchrotron radiation effects at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Beutner, B.

    2007-12-15

    The vacuum-ultra-violet Free Electron Laser in Hamburg (FLASH) is a linac driven SASE-FEL. High peak currents are produced using magnetic bunch compression chicanes. In these magnetic chicanes, the energy distribution along an electron bunch is changed by eff ects of Coherent Synchrotron Radiation (CSR). Energy changes in dispersive bunch compressor chicanes lead to transverse displacements along the bunch. These CSR induced displacements are studied using a transverse deflecting RF-structure. Experiments and simulations concerning the charge dependence of such transverse displacements are presented and analysed. In these experiments an over-compression scheme is used which reduces the peak current downstream the bunch compressor chicanes. Therefore other self interactions like space charge forces which might complicate the measurements are suppressed. Numerical simulations are used to analyse the beam dynamics under the influence of CSR forces. The results of these numerical simulations are compared with the data obtained in the over-compression experiments at FLASH. (orig.)

  10. Nonlinear Resonance Benchmarking Experiment at the CERN Proton Synchrotron

    CERN Document Server

    Hofmann, I; Giovannozzi, Massimo; Martini, M; Métral, Elias

    2003-01-01

    As a first step of a space charge - nonlinear resonance benchmarking experiment over a large number of turns, beam loss and emittance evolution were measured over 1 s on a 1.4 GeV kinetic energy flat-bottom in the presence of a single octupole. By lowering the working point towards the resonance a gradual transition from a loss-free core emittance blow-up to a regime dominated by continuous loss was found. Our 3D simulations with analytical space charge show that trapping on the resonance due to synchrotron oscillation causes the observed core emittance growth as well as halo formation, where the latter is explained as the source of the observed loss.

  11. Theoretical foundations of synchrotron and storage ring RF systems

    CERN Document Server

    Klingbeil, Harald; Lens, Dieter

    2015-01-01

    This course-tested text is an ideal starting point for engineers and physicists entering the field of particle accelerators. The fundamentals are comprehensively introduced, derivations of essential results are provided, and a consistent notation style used throughout the book allows readers to quickly familiarize themselves with the field, providing a solid theoretical basis for further studies.   Emphasis is placed on the essential features of the longitudinal motion of charged particle beams, together with the corresponding RF generation and power amplification devices for synchrotron and storage ring systems. In particular, electrical engineering aspects such as closed-loop control of system components are discussed.   The book also offers a valuable resource for graduate students in physics, electronics engineering, or mathematics looking for an introductory and self-contained text on accelerator physics.

  12. Electron cloud detection and characterization in the CERN Proton Synchrotron

    CERN Document Server

    Mahner, Edgar; Caspers, Friedhelm

    2008-01-01

    We describe a dedicated electron cloud experiment which was installed in the CERN Proton Synchrotron in 2007. The setup comprises shielded button-type pickups, a fast vacuum logging, a dipole magnet, and a stripline electrode to experimentally verify the beneficial effect of electron cloud clearing.The electron cloud effect was observed within the last milliseconds before ejection of the nominal LHC proton beam consisting of 72 bunches with 25 ns spacing. Measurements of electron flux at the wall and vacuum pressure are presented for a set of magnetic fields and bias voltages on the clearing electrode, showing that efficient electron cloud suppression can be obtained for appropriate clearing voltages but revealing an unexpectedly complex dependence on magnetic field and voltage.

  13. Modelling and control of neutron and synchrotron beamline positioning systems

    Science.gov (United States)

    Nneji, S. O.; Zhang, S. Y.; Kabra, S.; Moat, R. J.; James, J. A.

    2016-03-01

    Measurement of residual stress using neutron or synchrotron diffraction relies on the accurate alignment of the sample in relation to the gauge volume of the instrument. Automatic sample alignment can be achieved using kinematic models of the positioning system provided the relevant kinematic parameters are known, or can be determined, to a suitable accuracy. In this paper, the use of techniques from robotic calibration theory to generate kinematic models of both off-the-shelf and custom-built positioning systems is demonstrated. The approach is illustrated using a positioning system in use on the ENGIN-X instrument at the UK's ISIS pulsed neutron source comprising a traditional XYZΩ table augmented with a triple axis manipulator. Accuracies better than 100 microns were achieved for this compound system. Discussed here in terms of sample positioning systems these methods are entirely applicable to other moving instrument components such as beam shaping jaws and detectors.

  14. Unexpectedly wide rf-induced synchrotron sideband depolarizing resonances

    Science.gov (United States)

    Chu, C. M.; Ellison, T. J.; Lee, S. Y.; Rinckel, T.; Schwandt, P.; Sperisen, F.; von Przewoski, B.; Anferov, V. A.; Blinov, B. B.; Bychkov, M. A.; Caussyn, D. D.; Courant, E. D.; Crandell, D. A.; Derbenev, Ya. S.; Kaufman, W. A.; Krisch, A. D.; Lorenzon, W.; Nurushev, T. S.; Phelps, R. A.; Ratner, L. G.; Wong, V. K.; Ohmori, C.; Minty, M. G.; Martin, P. S.; Russell, A. D.; Sivers, D. W.

    1998-10-01

    Using an rf solenoid magnet, we studied the depolarization of a stored 104.1 MeV vertically polarized proton beam. The two primary rf depolarizing resonances were properly centered around the protons' circulation frequency fc, at fc(3-νs) and fc(νs-1), where νs is the spin tune; moreover, each resonance was roughly consistent with the expected width of about 720 Hz. Each primary rf resonance had two synchrotron sideband resonances at the expected frequencies. The two νs-1 sidebands were deep dips while the two 3-νs sidebands were very shallow; this was not expected. Moreover, all four sideband resonances were unexpectedly wider than the two primary resonances.

  15. Bounding Isotropic Lorentz Violation Using Synchrotron Losses at LEP

    CERN Document Server

    Altschul, Brett

    2009-01-01

    Some deviations from special relativity--especially isotropic effects--are most efficiently constrained using particles with velocities very close to 1. While there are extremely tight bounds on some of the relevant parameters coming from astrophysical observations, many of these rely on our having an accurate understanding of the dynamics of high-energy sources. It is desirable to have reliable laboratory constraints on these same parameters. The fastest-moving particles in a laboratory were electrons and positrons at LEP. The energetics of the LEP beams were extremely well understood, and measurements of the synchrotron emission rate indicates that that any isotropic deviation of the speed of light from 1 must be smaller than 1.2 x 10^(-15).

  16. Bounding isotropic Lorentz violation using synchrotron losses at LEP

    Science.gov (United States)

    Altschul, Brett

    2009-11-01

    Some deviations from special relativity—especially isotropic effects—are most efficiently constrained using particles with velocities very close to 1. While there are extremely tight bounds on some of the relevant parameters coming from astrophysical observations, many of these rely on our having an accurate understanding of the dynamics of these high-energy sources. It is desirable to have reliable laboratory constraints on these same parameters. The fastest-moving particles in a laboratory were electrons and positrons at LEP. The energetics of the LEP beams were extremely well understood, and measurements of the synchrotron emission rate indicate that the isotropic Lorentz violation coefficient |κ˜tr-(4)/(3)c00| must be smaller than 5×10-15.

  17. Physical Analysis of the Jovian Synchrotron Radio Emission

    Science.gov (United States)

    Santos-Costa, D.; Bolton, S. J.; Levin, S. M.; Thorne, R. M.

    2006-12-01

    We present results of our recent investigation of the Jovian synchrotron emission based on a particle transport code. The features of the two-dimensional brightness distributions, radio spectra and beaming curves are correlated to the different phenomena driven the dynamics of the electron radiation belts. The adiabatic invariant theory was used for performing this analysis work. The theoretical approach first enabled us to describe the electron radiation belts by modeling the interactions between high-energy trapped particles and plasmas, neutrals, moons, dust and magnetic field. Then radio observations were used to discuss the computed particle distributions in the inner magnetosphere of Jupiter. The simulated brightness mappings were compared with VLA observations made at two wavelengths (20 and 6 cm). The beaming curve comparisons at 13-cm wavelength were performed for different epochs in order to evaluate the dependence of the model to the geometric factor De. The computed radio spectra were discussed with measurements made in the [0.5-20] GHz radio band. The simulation results match the different remote observations very well and thus allowed us to study the phenomenology of the Jovian synchrotron radio emission. The analysis of the Jovian synchrotron emission demonstrates that during the inward particle transport, local losses associated with the Jovian moons set the extension and intensity of the synchrotron radiation along the magnetic equator. Close to the planet, trapped electrons suffer from the interactions with dust and magnetic field, resulting in the transport of particles toward the high latitudes. The quantity of particles transported away from the equator is sufficient to produce the measurable secondary radio emissions. The simulations show that the moon sweeping effect controls both the transport toward the planet and at high latitudes by reducing the abundance of particles constrained to populate the regions out of the equator. Among the

  18. Automated Tuning of the Advanced Photon Source Booster Synchrotron

    Science.gov (United States)

    Biedron, S. G.; Carwardine, J. A.; Milton, S. V.

    1997-05-01

    The acceleration cycle of the Advanced Photon Source (APS) booster synchrotron is completed within 250 ms and is repeated at 2 Hz. Unless properly corrected, transverse and longitudinal injection errors can lead to inefficient booster performance. Ramped-magnet tracking errors can also lead to losses during the acceleration cycle. In order to simplify daily operation, automated tuning methods have been developed. Through the use of empirically determined response functions, transfer line corrector magnets, and beam position monitor readings, the injection process is optimized by correcting the first turn trajectory to the measured closed orbit. An automated version of this correction technique has been implemented using the feedback-based program sddscontrollaw. Further automation is used to adjust and minimize tracking errors between the five main ramped power supplies. These tuning algorithms and their implementation are described here along with an evaluation of their! performance.

  19. Modelling and control of neutron and synchrotron beamline positioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Nneji, S.O., E-mail: Stephen.nneji@open.ac.uk [The Open University, Materials Engineering, Walton Hall, Milton Keynes, Buckinghamshire MK7 6AA (United Kingdom); Science and Technology Facility Council , Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, OX110QX Oxfordshire (United Kingdom); Zhang, S.Y.; Kabra, S. [Science and Technology Facility Council , Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, OX110QX Oxfordshire (United Kingdom); Moat, R.J.; James, J.A. [The Open University, Materials Engineering, Walton Hall, Milton Keynes, Buckinghamshire MK7 6AA (United Kingdom)

    2016-03-21

    Measurement of residual stress using neutron or synchrotron diffraction relies on the accurate alignment of the sample in relation to the gauge volume of the instrument. Automatic sample alignment can be achieved using kinematic models of the positioning system provided the relevant kinematic parameters are known, or can be determined, to a suitable accuracy. In this paper, the use of techniques from robotic calibration theory to generate kinematic models of both off-the-shelf and custom-built positioning systems is demonstrated. The approach is illustrated using a positioning system in use on the ENGIN-X instrument at the UK's ISIS pulsed neutron source comprising a traditional XYZΩ table augmented with a triple axis manipulator. Accuracies better than 100 microns were achieved for this compound system. Discussed here in terms of sample positioning systems these methods are entirely applicable to other moving instrument components such as beam shaping jaws and detectors.

  20. Applications of Parallel Computational Methods to Charged-Particle Beam Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kabel, A.; Cai, Y.; /SLAC; Dohlus, M.; /DESY; Sen, T.; /Fermilab; Uplenchwar, R.; /SLAC /DESY

    2007-10-16

    The availability of parallel computation hardware and the advent of standardized programming interfaces has made a new class of beam dynamics problems accessible to numerical simulations. We describe recent progress in code development for simulations of coherent synchrotron radiation and the weak-strong and strong-strong beam-beam interaction. Parallelization schemes will be discussed, and typical results will be presented.