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Sample records for berkeley escar storage ring

  1. Around the laboratories: Rutherford: Successful tests on bubble chamber target technique; Stanford (SLAC): New storage rings proposal; Berkeley: The HAPPE project to examine cosmic rays with superconducting magnets; The 60th birthday of Professor N.N. Bogolyubov; Argonne: Performance of the automatic film measuring system POLLY II

    CERN Multimedia

    1969-01-01

    Around the laboratories: Rutherford: Successful tests on bubble chamber target technique; Stanford (SLAC): New storage rings proposal; Berkeley: The HAPPE project to examine cosmic rays with superconducting magnets; The 60th birthday of Professor N.N. Bogolyubov; Argonne: Performance of the automatic film measuring system POLLY II

  2. Heavy ion storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Schuch, R.

    1987-01-01

    A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented.

  3. Autumn study on storage rings

    CERN Multimedia

    1974-01-01

    The first two weeks of October have seen storage ring people from accelerator Laboratories throughout the world at CERN to study the fundamental problems of very high energy protonproton colliding beam machines.

  4. A new storage-ring light source

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Alex [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-06-01

    A recently proposed technique in storage ring accelerators is applied to provide potential high-power sources of photon radiation. The technique is based on the steady-state microbunching (SSMB) mechanism. As examples of this application, one may consider a high-power DUV photon source for research in atomic and molecular physics or a high-power EUV radiation source for industrial lithography. A less challenging proof-of-principle test to produce IR radiation using an existing storage ring is also considered.

  5. Neutrino Signals in Electron-Capture Storage-Ring Experiments

    Directory of Open Access Journals (Sweden)

    Avraham Gal

    2016-06-01

    Full Text Available Neutrino signals in electron-capture decays of hydrogen-like parent ions P in storage-ring experiments at GSI are reconsidered, with special emphasis placed on the storage-ring quasi-circular motion of the daughter ions D in two-body decays P → D + ν e . It is argued that, to the extent that daughter ions are detected, these detection rates might exhibit modulations with periods of order seconds, similar to those reported in the GSI storage-ring experiments for two-body decay rates. New dedicated experiments in storage rings, or using traps, could explore these modulations.

  6. The Cryogenic Storage Ring CSR

    CERN Document Server

    von Hahn, Robert; Berg, Felix; Blaum, Klaus; Breitenfeldt, Christian; Fadil, Hisham; Fellenberger, Florian; Froese, Michael; George, Sebastian; Göck, Jürgen; Grieser, Manfred; Grussie, Florian; Guerin, Elisabeth A; Heber, Oded; Herwig, Philipp; Karthein, Jonas; Krantz, Claude; Kreckel, Holger; Lange, Michael; Laux, Felix; Lohmann, Svenja; Menk, Sebastian; Meyer, Christian; Mishra, Preeti M; Novotný, Oldřich; Connor, Aodh P O; Orlov, Dmitry A; Rappaport, Michael L; Repnow, Roland; Saurabh, Sunny; Schippers, Stefan; Schröter, Claus Dieter; Schwalm, Dirk; Schweikhard, Lutz; Sieber, Thomas; Shornikov, Andrey; Spruck, Kaija; Kumar, Sudhakaran Sunil; Ullrich, Joachim; Urbain, Xavier; Vogel, Stephen; Wilhelm, Patrick; Wolf, Andreas; Zajfman, Daniel

    2016-01-01

    An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 $\\pm$ 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion) and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas den...

  7. The cryogenic storage ring CSR

    Science.gov (United States)

    von Hahn, R.; Becker, A.; Berg, F.; Blaum, K.; Breitenfeldt, C.; Fadil, H.; Fellenberger, F.; Froese, M.; George, S.; Göck, J.; Grieser, M.; Grussie, F.; Guerin, E. A.; Heber, O.; Herwig, P.; Karthein, J.; Krantz, C.; Kreckel, H.; Lange, M.; Laux, F.; Lohmann, S.; Menk, S.; Meyer, C.; Mishra, P. M.; Novotný, O.; O'Connor, A. P.; Orlov, D. A.; Rappaport, M. L.; Repnow, R.; Saurabh, S.; Schippers, S.; Schröter, C. D.; Schwalm, D.; Schweikhard, L.; Sieber, T.; Shornikov, A.; Spruck, K.; Sunil Kumar, S.; Ullrich, J.; Urbain, X.; Vogel, S.; Wilhelm, P.; Wolf, A.; Zajfman, D.

    2016-06-01

    An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm-3 is derived, equivalent to a room-temperature pressure below 10-14 mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

  8. Nuclear Physics Experiments with Ion Storage Rings

    CERN Document Server

    Litvinova, Yu A; Blaum, K; Bosch, F; Brandau, C; Chen, L X; Dillmann, I; Egelhof, P; Geissel, H; Grisenti, R E; Hagmann, S; Heil, M; Heinz, A; Kalantar-Nayestanaki, N; Knöbel, R; Kozhuharov, C; Lestinsky, M; Ma, X W; Nilsson, T; Nolden, F; Ozawa, A; Raabe, R; Reed, M W; Reifarth, R; Sanjari, M S; Schneider, D; Simon, H; Steck, M; Stöhlker, T; Sun, B H; Tu, X L; Uesaka, T; Walker, P M; Wakasugi, M; Weick, H; Winckler, N; Woods, P J; Xu, H S; Yamaguchi, T; Yamaguchi, Y; Zhang, Y H

    2013-01-01

    In the last two decades a number of nuclear structure and astrophysics experiments were performed at heavy-ion storage rings employing unique experimental conditions offered by such machines. Furthermore, building on the experience gained at the two facilities presently in operation, several new storage ring projects were launched worldwide. This contribution is intended to provide a brief review of the fast growing field of nuclear structure and astrophysics research at storage rings.

  9. Beam Measurements in Storage Rings

    Science.gov (United States)

    Hofmann, Albert

    1996-05-01

    Beam measurements in storage rings are made to diagnose performance limitations and to gain knowledge of the beam behavior in view of improvements and to the benefit for other machines. In beam optics the measurement of the orbit or the trajectory with beam position monitors distributed around the ring reveals deflection errors. The overall focusing is checked by measuring the betatron frequency (tune) using a pulse or continuous excitation of the oscillation. Observing this oscillation with all the beam position monitors around the ring the beta function and the betatron phase advance are obtained. This measurement done for different momenta, i.e. RF-frequencies, gives the local chromaticity and its correction. The tune dependence on quadrupole strength gives the value of the local beta function. Synchrotron radiation is a powerful diagnostics tool and can give the beam cross section. Beam instabilities are investigated with similar methods. The growth or damping rates and frequencies of betatron and synchrotron oscillations, observed as a function of intensity, give a convolution of the resistive and reactive part of the transverse and longitudinal impedance with the spectrum of the oscillation mode. Coupled bunch instabilities are caused by narrow band impedances at particular frequencies while single traversal effects, including energy loss and bunch lengthening, are due to a broad band impedance. A model of the impedance can be constructed from such measurements done with different bunch lengths, tunes and other parameters. In some cases the element causing an instability can be identified. The dependence of the orbit and phase advance around the ring on intensity can give the location of impedances. To probe the impedance at very high frequencies the effects on very short bunches or the energy loss of a continuous beam due to its Schottky noise are measured. The beam energy, usually known from magnetic measurements, can be obtained directly with high

  10. Longitudinal dynamics in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Colton, E.P.

    1986-01-01

    The single-particle equations of motion are derived for charged particles in a storage ring. Longitudinal space charge is included in the potential assuming an infinitely conducting circular beam pipe with a distributed inductance. The framework uses Hamilton's equations with the canonical variables phi and W. The Twiss parameters for longitudinal motion are also defined for the small amplitude synchrotron oscillations. The space-charge Hamiltonian is calculated for both parabolic bunches and ''matched'' bunches. A brief analysis including second-harmonic rf contributions is also given. The final sections supply calculations of dynamical quantities and particle simulations with the space-charge effects neglected.

  11. The cryogenic storage ring project

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Robert von; Blaum, Klaus; Becker, Arno; Fellenberger, Florian; George, Sebastian; Grieser, Manfred; Grussie, Florian; Herwig, Philipp; Krantz, Claude; Kreckel, Holger; Lange, Michael; Menk, Sebastian; Repnow, Roland; Vogel, Stephen; Wolf, Andreas [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Spruck, Kaija [Justus-Liebig-Universitaet, Giessen (Germany)

    2014-07-01

    At MPIK the electrostatic cryogenic storage ring CSR is nearing completion. At beam energies of 20 to 300 keV per charge unit and 35 m circumference the CSR will allow experiments in a cryogenic environment providing conditions of extremely low vacuum and heat radiation. By using liquid helium at 2 K for cryopumping, the projected vacuum (confirmed at a prototype) lies at 1E-13 mbar or below, ensuring long storage times for slow singly charged and highly charged ions, molecules and clusters. Moreover, phase space cooling by electrons will be implemented. The internal quantum states of molecular and cluster ions can be cooled to low temperature, yielding well defined vibrational and for smaller systems also rotational structures. In the CSR construction, the cryogenic ion beam vacuum system has been set up. Extensive tests confirming the criteria on heat flow, alignment and high-voltage stability were successfully completed on the first quadrant. In addition beam diagnostic units for electric pickup signals and spatial profiles, detectors for neutral and charged fragments, the injection beam line, and an electron cooling device are under construction.

  12. The "g-2" Muon Storage Ring

    CERN Multimedia

    1974-01-01

    The "g-2" muon storage ring, shortly before completion in June 1974. Bursts of pions (from a target, hit by a proton beam from the 26 GeV PS) are injected and polarized muons from their decay are captured on a stable orbit. When the muons decay too, their precession in the magnetic field of the storage ring causes a modulation of the decay-electron counting rate, from which the muon's anomalous magnetic moment can be determined. In 1977, the "g-2" magnets were modified to build ICE (Initial Cooling Experiment), a proton and antiproton storage ring for testing stochastic and electron cooling. Later on, the magnets had a 3rd life, when the ion storage ring CELSIUS was built from them in Uppsala. For later use as ICE, see 7711282, 7802099, 7809081,7908242.

  13. Storage rings, internal targets and PEP

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, J.E.

    1986-11-01

    Storage rings with internal targets are described, using PEP as an example. The difference between electrons and heavier particles such as protons, antiprotons, and heavy ions is also discussed because it raises possibilities of bypass insertions for more exotic experiments. PEP is compared to other rings in various contexts to verify the assertion that it is an ideal ring for many fundamental and practical applications that can be carried on simultaneously. (LEW)

  14. Storage-ring Electron Cooler for Relativistic Ion Beams

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Fanglei [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Derbenev, Yaroslav [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Guo, Jiquan [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Johnson, Rolland P. [Muons Inc., Batavia, IL (United States); Krafft, Geoffrey A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Morozov, Vasiliy [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, Yuhong [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-05-01

    Application of electron cooling at ion energies above a few GeV has been limited due to reduction of electron cooling efficiency with energy and difficulty in producing and accelerating a high-current high-quality electron beam. A high-current storage-ring electron cooler offers a solution to both of these problems by maintaining high cooling beam quality through naturally-occurring synchrotron radiation damping of the electron beam. However, the range of ion energies where storage-ring electron cooling can be used has been limited by low electron beam damping rates at low ion energies and high equilibrium electron energy spread at high ion energies. This paper reports a development of a storage ring based cooler consisting of two sections with significantly different energies: the cooling and damping sections. The electron energy and other parameters in the cooling section are adjusted for optimum cooling of a stored ion beam. The beam parameters in the damping section are adjusted for optimum damping of the electron beam. The necessary energy difference is provided by an energy recovering SRF structure. A prototype linear optics of such storage-ring cooler is presented.

  15. Inauguration ceremony for the Intersecting Storage Rings

    CERN Multimedia

    1971-01-01

    The inauguration ceremony for the Intersecting Storage Rings (ISR) was held on 16 October 1971. Kjell Johnsen is seen in the picture handing a symbolic key to the ISR to Edoardo Amaldi. From left to right on the podium: Victor Frederik Weisskopf, former Director-General; M Antonioz; Willibald Jentschke as Director-General of CERN, and on the other side Werner Heisenberg.

  16. First interactions from the Intersecting Storage Rings

    CERN Multimedia

    1971-01-01

    On 27 January 1971, Kjell Johnsen, who led the construction team which built the Intersecting Storage Rings (ISR), announced that the first ever interactions from colliding protons had been recorded. On the left are Franco Bonaudi, who was responsible for the civil engineering and Dirk Neet, who later took charge of ISR operations.

  17. Electron Storage Ring Development for ICS Sources

    Energy Technology Data Exchange (ETDEWEB)

    Loewen, Roderick [Lyncean Technologies, Inc., Palo Alto, CA (United States)

    2015-09-30

    There is an increasing world-wide interest in compact light sources based on Inverse Compton Scattering. Development of these types of light sources includes leveraging the investment in accelerator technology first developed at DOE National Laboratories. Although these types of light sources cannot replace the larger user-supported synchrotron facilities, they offer attractive alternatives for many x-ray science applications. Fundamental research at the SLAC National Laboratory in the 1990’s led to the idea of using laser-electron storage rings as a mechanism to generate x-rays with many properties of the larger synchrotron light facilities. This research led to a commercial spin-off of this technology. The SBIR project goal is to understand and improve the performance of the electron storage ring system of the commercially available Compact Light Source. The knowledge gained from studying a low-energy electron storage ring may also benefit other Inverse Compton Scattering (ICS) source development. Better electron storage ring performance is one of the key technologies necessary to extend the utility and breadth of applications of the CLS or related ICS sources. This grant includes a subcontract with SLAC for technical personnel and resources for modeling, feedback development, and related accelerator physics studies.

  18. Perspective for a compact electrostatic storage ring : Miniature quadrilateral electrostatic storage ring

    OpenAIRE

    El Ghazaly, Mohamed ,

    2013-01-01

    International audience; A flexible, compact-sized electrostatic storage ring is being designed at the King Abdulaziz City for Science and Technology (KACST). The design features a quadratic shaped ring with four 90° bending corners and relies exclusively on quadrupoles to act on the stored ion beam.

  19. Storage-ring Electron Cooler for Relativistic Ion Beams

    CERN Document Server

    Lin, F; Douglas, D; Guo, J; Johnson, R P; Krafft, G; Morozov, V S; Zhang, Y

    2016-01-01

    Application of electron cooling at ion energies above a few GeV has been limited due to reduction of electron cooling efficiency with energy and difficulty in producing and accelerating a high-current high-quality electron beam. A high-current storage-ring electron cooler offers a solution to both of these problems by maintaining high cooling beam quality through naturally-occurring synchrotron radiation damping of the electron beam. However, the range of ion energies where storage-ring electron cooling can be used has been limited by low electron beam damping rates at low ion energies and high equilibrium electron energy spread at high ion energies. This paper reports a development of a storage ring based cooler consisting of two sections with significantly different energies: the cooling and damping sections. The electron energy and other parameters in the cooling section are adjusted for optimum cooling of a stored ion beam. The beam parameters in the damping section are adjusted for optimum damping of the...

  20. Feasibility of a ring FEL at low emittance storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Agapov, I., E-mail: ilya.agapov@xfel.eu

    2015-09-01

    A scheme for generating coherent radiation at latest generation low emittance storage rings such as PETRA III at DESY (Balewski et al., 2004 [1]) is proposed. The scheme is based on focusing and subsequent defocusing of the electron beam in the longitudinal phase space at the undulator location. The expected performance characteristics are estimated for radiation in the wavelength range of 500–1500 eV. It is shown that the average brightness is increased by several orders of magnitude compared to spontaneous undulator radiation, which can open new perspectives for photon-hungry soft X-ray spectroscopy techniques.

  1. Chaotic dynamics in a storage-ring Free Electron Laser

    CERN Document Server

    De Ninno, G; Bruni, C; Couprie, Marie Emmanuelle

    2002-01-01

    The temporal dynamics of a storage-ring Free Electron Laser is here investigated with particular attention to the case in which an external modulation is applied to the laser-electron beam detuning. The system is shown to produce bifurcations, multi-furcations as well as chaotic regimes. The peculiarities of this phenomenon with respect to the analogous behavior displayed by conventional laser sources are pointed out. Theoretical results, obtained by means of a phenomenological model reproducing the evolution of the main statistical parameters of the system, are shown to be in a good agreement with experiments carried out on the Super-ACO Free Electron Laser.

  2. Introductory statistical mechanics for electron storage rings

    Science.gov (United States)

    Jowett, John M.

    1987-02-01

    These lectures concentrate on statistical phenomena in electron storage rings. A stored electron beam is a dissipative, fluctuating system far from equilibrium whose mathematical description can be based upon non-equilibrium statistical mechanics. Stochastic differential equations are used to describe the quantum fluctuations of synchrotron radiation which is the main cause of randomness in electron dynamics. Fluctuating radiation reaction forces can be described via stochastic terms in Hamilton's equations of motion. Normal modes of particle motion, radiation damping effects, quantum diffusion in single-particle phase space are all discussed in this statistical formalism. (AIP)

  3. FLSR - The Frankfurt low energy storage ring

    Science.gov (United States)

    Stiebing, K. E.; Alexandrov, V.; Dörner, R.; Enz, S.; Kazarinov, N. Yu.; Kruppi, T.; Schempp, A.; Schmidt Böcking, H.; Völp, M.; Ziel, P.; Dworak, M.; Dilfer, W.

    2010-02-01

    An electrostatic storage ring for low-energy ions with a design energy of 50 keV is presently being set up at the Institut für Kernphysik der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany (IKF). This new device will provide a basis for new experiments on the dynamics of ionic and molecular collisions, as well as for high precision and time resolved laser spectroscopy. In this article, the design parameters of this instrument are reported.

  4. Storage ring electric dipole moment experiments

    Science.gov (United States)

    Morse, William M.; Storage Ring EDM Collaboration

    2013-10-01

    Dedicated electric dipole moment (edm) searches have been done only for neutral systems. We discuss in this talk dedicated storage ring proposals for measuring edms of charged particles. The statistical error dominates over the systematic error for the neutron and mercury atom edm searches. Large numbers of particles are available today from modern polarized sources at several accelerators. A proposed proton edm experiment at BNL would improve the present proton edm limit by a factor of 104. A "precursor" deuteron edm experiment has been proposed at COSY, Juelich, Germany. This would be the first measurement of the deuteron edm.

  5. Design Considerations for High Energy Electron -- Positron Storage Rings

    Science.gov (United States)

    Richter, B.

    1966-11-01

    High energy electron-positron storage rings give a way of making a new attack on the most important problems of elementary particle physics. All of us who have worked in the storage ring field designing, building, or using storage rings know this. The importance of that part of storage ring work concerning tests of quantum electrodynamics and mu meson physics is also generally appreciated by the larger physics community. However, I do not think that most of the physicists working tin the elementary particle physics field realize the importance of the contribution that storage ring experiments can make to our understanding of the strongly interacting particles. I would therefore like to spend the next few minutes discussing the sort of things that one can do with storage rings in the strongly interacting particle field.

  6. Search for electric dipole moments in storage rings

    Directory of Open Access Journals (Sweden)

    Lenisa Paolo

    2016-01-01

    Full Text Available The JEDI collaboration aims at making use of storage ring to provide the most precise measurement of the electric dipole moments of hadrons. The method makes exploits a longitudinal polarized beam. The existence an electric dipole moment would generate a torque slowly twisting the particle spin out of plan of the storage ring into the vertical direction. The observation of non zero electric dipole moment would represent a clear sign of new physics beyond the Standard Model. Feasiblity tests are presently undergoing at the COSY storage ring Forschungszentrum Jülich (Germany, to develop the novel techniques to be implemented in a future dedicated storage ring.

  7. Characterization of a new electrostatic storage ring for photofragmentation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, H. B., E-mail: hbjp@phys.au.dk; Svendsen, A.; Harbo, L. S.; Kiefer, H. V.; Kjeldsen, H.; Lammich, L.; Andersen, L. H. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Toker, Y. [Departement of Physics, Bar Ilan University, Ramat Gan 5290002 (Israel)

    2015-06-15

    We describe the design of and the first commissioning experiments with a newly constructed electrostatic storage ring named SAPHIRA (Storage Ring in Aarhus for PHoton-Ion Reaction Analysis). With an intense beam of Cu{sup −} at 4 keV, the storage ring is characterized in terms of the stored ion beam decay rate, the longitudinal spreading of an injected ion bunch, as well as the direct measurements of the transverse spatial distributions under different conditions of storage. The ion storage stability in SAPHIRA was investigated systematically in a selected region of its electrical configuration space.

  8. Astrochemistry at the Cryogenic Storage Ring

    Science.gov (United States)

    Kreckel, Holger; Becker, Arno; Blaum, Klaus; Breitenfeldt, Christian; George, Sebastian; Göck, Jürgen; Grieser, Manfred; Grussie, Florian; Guerin, Elisabeth; Heber, Oded; Karthein, Jonas; Krantz, Claude; Meyer, Christian; Mishra, Preeti; Novotny, Oldrich; O'Connor, Aodh; Saurabh, Sunny; Schippers, Stefan; Spruck, Kaija; Kumar, S. Sunil; Urbain, Xavier; Vogel, Stephen; von Hahn, Robert; Wilhelm, Patrick; Wolf, Andreas; Zajfman, Daniel

    2017-01-01

    Almost 200 different molecular species have been identified in space, and this number continues to grow steadily. This surprising molecular diversity bears witness to an active reaction network, in which molecular ions are the main drivers of chemistry in the gas phase. To study these reactions under controlled conditions in the laboratory is a major experimental challenge. The new Cryogenic Storage Ring (CSR) that has recently been commissioned at the Max Planck Institute for Nuclear Physics in Heidelberg will serve as an ideal testbed to study cold molecular ions in the gas phase. With residual gas densities of CSR will allow for merged beams collision studies involving molecular ions, neutral atoms, free electrons and photons under true interstellar conditions.

  9. Unicell structure for superconducting storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Danby, G.; DeVito, B.; Jackson, J.; Keohane, G.; Lee, Y.Y.; Phillips, R.; Plate, S.; Repeta, L.; Skaritka, J.; Smith, L.

    1985-01-01

    Mechanically integrated, magnetically decoupled storage rings were designed for a heavy ion collider for 100 GeV/amu Au, at B = 2.7T. New concepts were developed, including detailed engineering design and cost estimates. A ''unicell'' contains a half-cell of both rings within a single He vessel. The unicell design is optimized for economical mass production. Survey pads welded to the laminations provide external fiducials to locate the magnet cores. Roller bearing self aligning supports accommodate cool-down shrinkage. The design tolerates relative motion of components resulting from longitudinal shrinkage in the approx.15 m long unicell without affecting performance. Magnetic and physical lengths are the same, eliminating waste space. ''Achromatic'' quadrupoles with sextupoles at both ends are located on a common precision beam tube which aligns and supports a pick-up electrode. The unicell accommodates longer dipoles compared to conventional designs, reducing B/sub max/, stored energy, and the volume of iron and superconductor. Applications to future machines will be discussed.

  10. Unicell structure for superconducting storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Danby, G.; DeVito, B.; Jackson, J.; Keohane, G.; Lee, Y.Y.; Phillips, R.; Plate, S.; Repeta, L.; Skaritka, J.; Smith, L.

    1985-10-01

    Mechanically integrated, magnetically decoupled storage rings were designed for a heavy ion collider for 100 GeV/amu Au, at B=2.7T. New concepts were developed, including detailed engineering design and cost estimates. A ''unicell'' contains a half-cell of both rings within a single He vessel. The unicell design is optimized for economical mass production. Survey pads welded to the laminations provide external fiducials to locate the magnet cores. Roller bearing self aligning supports accommodate cool-down shrinkage. The design tolerates relative motion of components resulting from longitudinal shrinkage in the about15 m long unicell without affecting performance. Magnetic and physical lengths are the same, eliminating waste space. ''Achromatic'' quadrupoles with sextupoles at both ends are located on a common precision beam tube which aligns and supports a pick-up electrode. The unicell accommodates longer dipoles compared to conventional designs, reducing B /SUB max'/ stored energy, and the volume of iron and superconductor. Applications to future machines will be discussed.

  11. Design study of the storage ring EUTERPE

    Science.gov (United States)

    Xi, Boling; Botman, J. I. M.; Timmermans, C. J.; Hagedoorn, H. L.

    1992-05-01

    At present the 400 MeV electron storage ring EUTERPE is being constructed at the Eindhoven University of Technology. It is a university project set up for studies of charged particle beam dynamics and applications of synchroton radiation, and for the education of students in these fields. The design of the ring is described in this paper. Considering the requirements of users in different fields, a lattice based on a so-called triple bend achromat structure with a high flexibility has been chosen. With this lattice, different optical options, including the HBSB (high brightness, small beam), the SBL (short bunch length) and the HLF (high light flux) modes can be realized. A small emittance of 7 nm rad and a short bunch length of the order of several mm can be achieved. In the first phase the synchrotron radiation in the UV and XUV region (the critical wavelength is 8.3 nm) will be provided from the regular dipole magnets. Later on, a 10 T wiggler magnet and other special inserters will be added, and other applications and beam dynamics studies will be feasible. Bending magnets are of the parallel faced C configuration. The effective aperture of the vacuum chamber is 2.3 cm (vertical) in the bending magnets and 4.7 cm elsewhere with a working vacuum condition of 10-9 Torr. Collective effects have been studied initially. First calculations indicate that a lifetime of several hours, influenced by the Touschek effect and residual gas scattering will be achievable for a 200 mA beam in the HLF mode for the standard rf parameters. A 70 MeV racetrack microtron will serve as injector for the ring.

  12. Bunch transverse emittance increase in electron storage rings

    Institute of Scientific and Technical Information of China (English)

    GAO Jie

    2009-01-01

    In this paper a theoretical framework to estimate the bunch transverse emittance growing in electron storage rings due to short range transverse wakefield of the machine is established. New equilibrium emittance equations are derived and applied to explain the experimentally obtained results in ATF damping ring. This equation will be useful for linear collider damping ring design.

  13. VUV optical ring resonator for Duke storage ring free electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.H.; Litvinenko, V.N.; Madey, J.M.J. [Duke Univ., Durham, NC (United States)] [and others

    1995-12-31

    The conceptual design of the multifaceted-mirror ring resonator for Duke storage ring VUV FEL is presented. The expected performance of the OK-4 FEL with ring resonator is described. We discuss in this paper our plans to study reflectivity of VUV mirrors and their resistivity to soft X-ray spontaneous radiation from OK-4 undulator.

  14. Calibration of the linear optics in the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    TIAN Shunqiang; LIU Guimin; ZHANG Wenzhi; LI Haohu; ZHANG Manzhou; HOU Jie; CHEN Guangling

    2008-01-01

    Phase Ⅰ commissioning of the SSRF storage ring at 3.0 GeV was ended with encouraging results. Distortions and calibrations of the linear optics during the storage ring commissioning are discussed in this paper. The calibration procedure has reduced sextupole-additional focusing effects by minimizing closed orbit deviation and corrected quadrupole magnetic coefficients with the linear optics from closed orbit (LOCO) technique. After fitting the closed orbit response matrix, linear optics of the storage ring is substantially corrected, and the measured parameters agree well with the design. Four optics modes were commissioned, and relevant machine physics studies were carried out. Their results are summarized.

  15. Physics issues in diffraction limited storage ring design

    Institute of Scientific and Technical Information of China (English)

    FAN Wei; BAI ZhengHe; GAO WeiWei; FENG GuangYao; LI WeiMin; WANG Lin; HE DuoHui

    2012-01-01

    Diffraction limited electron storage ring is considered a promising candidate for future light sources,whose main characteristics are higher brilliance,better transverse coherence and better stability.The challenge of diffraction limited storage ring design is how to achieve the ultra low beam emittance with acceptable nonlinear performance.Effective linear and nonlinear parameter optimization methods based on Artificial Intelligence were developed for the storage ring physical design.As an example of application,partial physical design of HALS (Hefei Advanced Light Source),which is a diffraction limited VUV and soft X-ray light source,was introduced.Severe emittance growth due to the Intra Beam Scattering effect,which is the main obstacle to achieve ultra low emittance,was estimated quantitatively and possible cures were discussed.It is inspiring that better performance of diffraction limited storage ring can be achieved in principle with careful parameter optimization.

  16. Physics issues in diffraction limited storage ring design

    Science.gov (United States)

    Fan, Wei; Bai, ZhengHe; Gao, WeiWei; Feng, GuangYao; Li, WeiMin; Wang, Lin; He, DuoHui

    2012-05-01

    Diffraction limited electron storage ring is considered a promising candidate for future light sources, whose main characteristics are higher brilliance, better transverse coherence and better stability. The challenge of diffraction limited storage ring design is how to achieve the ultra low beam emittance with acceptable nonlinear performance. Effective linear and nonlinear parameter optimization methods based on Artificial Intelligence were developed for the storage ring physical design. As an example of application, partial physical design of HALS (Hefei Advanced Light Source), which is a diffraction limited VUV and soft X-ray light source, was introduced. Severe emittance growth due to the Intra Beam Scattering effect, which is the main obstacle to achieve ultra low emittance, was estimated quantitatively and possible cures were discussed. It is inspiring that better performance of diffraction limited storage ring can be achieved in principle with careful parameter optimization.

  17. Estimates of CSR Instability Thresholds for Various Storage Rings

    CERN Document Server

    Zimmermann, Frank

    2010-01-01

    We review the key predictions and conditions by several authors for the onset of longitudinal instabilities due to coherent synchrotron radiation (CSR), and evaluate them numerically for various storage rings, namely the KEKB High Energy Ring (HER) & Low Energy Ring (LER), SuperKEKB HER & LER, old and new designs of the SuperKEKB Damping Ring (DR), SuperB HER & LER, CLIC DR (2009 and 2010 design parameters), SLC DR, and ATF DR. We show that the theoretical uncertainty in the instability onset is at least at the level of 20-30% in bunch intensity. More importantly, we present some doubts about the general applicability for many of these storage rings of some commonly used formulae. To cast further light on these questions, an experiment at lower beam energy on the ATF Damping Ring is proposed.

  18. Storage ring at HIE-ISOLDE Technical design report

    NARCIS (Netherlands)

    Grieser, M.; Litvinov, Yu. A.; Raabe, R.; Blaum, K.; Blumenfeld, Y.; Butler, P. A.; Wenander, F.; Woods, P. J.; Aliotta, M.; Andreyev, A.; Artemyev, A.; Atanasov, D.; Aumann, T.; Balabanski, D.; Barzakh, A.; Batist, L.; Bernardes, A. -P.; Bernhardt, D.; Billowes, J.; Bishop, S.; Borge, M.; Borzov, I.; Boston, A. J.; Brandau, C.; Catford, W.; Catherall, R.; Cederkall, J.; Cullen, D.; Davinson, T.; Dillmann, I.; Dimopoulou, C.; Dracoulis, G.; Duellmann, Ch. E.; Egelhof, P.; Estrade, A.; Fischer, D.; Flanagan, K.; Fraile, L.; Fraser, M. A.; Freeman, S. J.; Geissel, H.; Gerl, J.; Greenlees, P.; Grisenti, R. E.; Habs, D.; von Hahn, R.; Hagmann, S.; Hausmann, M.; He, J. J.; Heil, M.; Huyse, M.; Jenkins, D.; Jokinen, A.; Jonson, B.; Joss, D. T.; Kadi, Y.; Kalantar-Nayestanaki, N.; Kay, B. P.; Kiselev, O.; Kluge, H. -J.; Kowalska, M.; Kozhuharov, C.; Kreim, S.; Kroell, T.; Kurcewicz, J.; Labiche, M.; Lemmon, R. C.; Lestinsky, M.; Lotay, G.; Ma, X. W.; Marta, M.; Meng, J.; Muecher, D.; Mukha, I.; Mueller, A.; Murphy, A. St J.; Neyens, G.; Nilsson, T.; Nociforo, C.; Noertershaeuser, W.; Page, R. D.; Pasini, M.; Petridis, N.; Pietralla, N.; Pfuetzner, M.; Podolyak, Z.; Regan, P.; Reed, M. W.; Reifarth, R.; Reiter, P.; Repnow, R.; Riisager, K.; Rubio, B.; Sanjari, M. S.; Savin, D. W.; Scheidenberger, C.; Schippers, S.; Schneider, D.; Schuch, R.; Schwalm, D.; Schweikhard, L.; Shubina, D.; Siesling, E.; Simon, H.; Simpson, J.; Smith, J.; Sonnabend, K.; Steck, M.; Stora, T.; Stoehlker, T.; Sun, B.; Surzhykov, A.; Suzaki, F.; Tarasov, O.; Trotsenko, S.; Tu, X. L.; Van Duppen, P.; Volpe, C.; Voulot, D.; Walker, P. M.; Wildner, E.; Winckler, N.; Winters, D. F. A.; Wolf, A.; Xu, H. S.; Yakushev, A.; Yamaguchi, T.; Yuan, Y. J.; Zhang, Y. H.; Zuber, K.; Bosch, F.M.

    2012-01-01

    We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams tha

  19. Exact solutions for the spin tune for model storage rings

    CERN Document Server

    Mane, S R

    2002-01-01

    We present exact analytical expressions for the spin tune for arbitrary values of the orbital action for several storage ring models. The models we treat contain Siberian Snakes, the use of which is essential to preserve the polarization of beams in high-energy proton storage rings. Our solutions contain some novel features. We also prove a previously conjectured claim about the behavior of spin tuneshifts in rings with multiple Snakes. The conjecture is based on numerical simulations, but our proof is analytical, and also nonperturbative.

  20. Storage rings for investigation of ion-atom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Schuch, R.

    1987-08-01

    In this survey, we give a brief description of synchrotron storage rings for heavy ions, and examples for their use in ion-atom collision physics. The compression of the phase space distribution of the ions by electron cooling, and the gain factors of in-ring experiments compared to single-pass experiments are explained. Some examples of a new generation of ion-atom collision experiments which may become feasible with storage rings are given. These include the studies of angular differential single- and double-electron capture cross sections, the production of slow highly charged recoil ions, and atomic collision processes using decelerated and crossed beam. 30 refs.

  1. Ultra High Precision with a Muon Storage Ring

    CERN Document Server

    Roberts, B L

    2002-01-01

    The Muon $(g-2)$ experiment, E821, at the Brookhaven AGS has the goal to measure the muon anomalous magnetic moment to a relative accuracy of $\\pm 3.5 \\times 10^{-7}$. A superferric 14 m diameter storage ring has been constructed and an averaged magnetic field uniformity over the 90 mm diameter muon storage region of $\\pm$ 1 part per million (ppm) has been achieved. A truncated double-cosine superconducting septum magnet (the inflector) was constructed along with a fast non-ferric kicker. The performance of the storage ring, along with the physics results are reviewed.

  2. Design of a novel electrostatic ion storage ring at KACST

    CERN Document Server

    Ghazaly, M O A El; Welsch, C P; Alharbi, H H

    2013-01-01

    A new electrostatic storage ring for beams at energies up to 30keV.q is currently under development at the National Centre for Mathematics and Physics (NCMP), King Abdulaziz City for Science and Technology (KACST). The ring design is based on the existing electrostatic storage rings, but stretches significantly beyond them in that it shall form the core of a unique flexible experimental facility at KACST. The lattice of this ring has been designed in a way that enables the use of state-of-the-art experimental methods to study electron-ion, laser-ion, and ion-neutral beams interactions. The lattice design also allows for a future upgrade of the ring to a double storage ring structure that would enable ion-ion beam interactions to be performed. In this paper, we present the design of this ring with a focus on beam dynamics calculations for the 7o single-bend racetrack layout. The study is principally based on the SIMION8 program. We complemented this study further by using purpose-written routine and MAD-X simu...

  3. Simulation of Spin-orbit Dynamics in Storage Rings

    Science.gov (United States)

    Ivanov, A.; Andrianov, S.; Senichev, Yu.

    2016-09-01

    In the article a mapping approach based on nonlinear matrix integration for longterm spin-orbit dynamics simulation is briefly described. Using this technique the nonlinear effects of spin dynamics in an electrostatics storage ring are investigated. Namely, the fringe fields, the energy conservation law and the random field errors are considered. The necessity of examination of such effects arises, for example, in the storage ring design for search the Electrical Dipole Moment of proton and deuteron. The EDM ring is proposed to measure EDM using the spin transformation of polarized particle in the magneto-electrostatic elements of the ring. The article consists of short description of the spin-orbit simulation results based on the nonlinear model.

  4. SPARC Collaboration: New Strategy for Storage Ring Physics at FAIR

    CERN Document Server

    Stöhlker, Thomas; Bräuning-Demian, Angela; Lestinsky, Michael; Herfurth, Frank; Maier, Rudolf; Prasuhn, Dieter; Schuch, Reinhold; Steck, Markus

    2014-01-01

    SPARC collaboration at FAIR pursues the worldwide unique research program by utilizing storage ring and trapping facilities for highly-charged heavy ions. The main focus is laid on the exploration of the physics at strong, ultra-short electromagnetic fields including the fundamental interactions between electrons and heavy nuclei as well as on the experiments at the border between nuclear and atomic physics. Very recently SPARC worked out a realization scheme for experiments with highly-charged heavy-ions at relativistic energies in the High-Energy Storage Ring HESR and at very low-energies at the CRYRING coupled to the present ESR. Both facilities provide unprecedented physics opportunities already at the very early stage of FAIR operation. The installation of CRYRING, dedicated Low-energy Storage Ring (LSR) for FLAIR, may even enable a much earlier realisation of the physics program of FLAIR with slow anti-protons.

  5. Workshop on compact storage ring technology: applications to lithography

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-30

    Project planning in the area of x-ray lithography is discussed. Three technologies that are emphasized are the light source, the lithographic technology, and masking technology. The needs of the semiconductor industry in the lithography area during the next decade are discussed, particularly as regards large scale production of high density dynamic random access memory devices. Storage ring parameters and an overall exposure tool for x-ray lithography are addressed. Competition in this area of technology from Germany and Japan is discussed briefly. The design of a storage ring is considered, including lattice design, magnets, and beam injection systems. (LEW)

  6. Isochronicity Correction in the CR Storage Ring

    CERN Document Server

    Litvinov, S; Weick, H; Dolinskii, A

    2013-01-01

    A challenge for nuclear physics is to measure masses of exotic nuclei up to the limits of nuclear existence which are characterized by low production cross sections and short half-lives. The large acceptance Collector Ring (CR) at FAIR tuned in the isochronous ion-optical mode offers unique possibilities for measuring short-lived and very exotic nuclides. However, in a ring designed for maximal acceptance, many factors limit the resolution. One point is a limit in time resolution inversely proportional to the transverse emittance. But most of the time aberrations can be corrected and others become small for large number of turns. We show the relations of the time correction to the corresponding transverse focusing and that the main correction for large emittance corresponds directly to the chromaticity correction for transverse focusing of the beam. With the help of Monte-Carlo simulations for the full acceptance we demonstrate how to correct the revolution times so that in principle resolutions of dm/m=1E-6 ...

  7. Applying Frequency Map Analysis to the Australian Synchrotron Storage Ring

    CERN Document Server

    Tan, Yaw-Ren E; Le Blanc, Gregory Scott

    2005-01-01

    The technique of frequency map analysis has been applied to study the transverse dynamic aperture of the Australian Synchrotron Storage Ring. The results have been used to set the strengths of sextupoles to optimise the dynamic aperture. The effects of the allowed harmonics in the quadrupoles and dipole edge effects are discussed.

  8. DESIGN OF VISIBLE DIAGNOSTIC BEAMLINE FOR NSLS2 STORAGE RING

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, W.; Fernandes, H.; Hseuh, H.; Kosciuk, B.; Krinsky, S.; Singh, O.

    2011-03-28

    A visible synchrotron light monitor (SLM) beam line has been designed at the NSLS2 storage ring, using the bending magnet radiation. A retractable thin absorber will be placed in front of the first mirror to block the central x-rays. The first mirror will reflect the visible light through a vacuum window. The light is guided by three 6-inch diameter mirrors into the experiment hutch. In this paper, we will describe design work on various optical components in the beamline. The ultra high brightness NSLS-II storage ring is under construction at Brookhaven National Laboratory. It will have 3GeV, 500mA electron beam circulating in the 792m ring, with very low emittance (0.9nm.rad horizontal and 8pm.rad vertical). The ring is composed of 30 DBA cells with 15 fold symmetry. Three damping wigglers will be installed in long straight sections 8, 18 and 28 to lower the emittance. While electrons pass through the bending magnet, synchrotron radiation will be generated covering a wide spectrum. There are other insertion devices in the storage ring which will generate shorter wavelength radiation as well. Synchrotron radiation has been widely used as diagnostic tool to measure the transverse and longitudinal profile. Three synchrotron light beam lines dedicated for diagnostics are under design and construction for the NSLS-II storage ring: two x-ray beam lines (pinhole and CRL) with the source points from Cell 22 BM{_}A (first bending in the DBA cell) and Cell22 three-pole wiggler; the third beam line is using visible part of radiation from Cell 30 BM{_}B (second bending magnet from the cell). Our paper focuses on the design of the visible beam line - SLM.

  9. Performance of high-resolution position-sensitive detectors developed for storage-ring decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, T., E-mail: yamaguti@phy.saitama-u.ac.jp [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Suzaki, F. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Izumikawa, T. [RI Center, Niigata University, Niigata 951-8510 (Japan); Miyazawa, S. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Morimoto, K. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Suzuki, T. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Tokanai, F. [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Furuki, H.; Ichihashi, N.; Ichikawa, C. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Kitagawa, A. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Kuboki, T. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Momota, S. [School of Environmental Science and Engineering, Kochi University of Technology, Kochi 782-8502 (Japan); Nagae, D. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Nagashima, M.; Nakamura, Y. [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Nishikiori, R.; Niwa, T. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Ohtsubo, T. [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Ozawa, A. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); and others

    2013-12-15

    Highlights: • Position-sensitive detectors were developed for storage-ring decay spectroscopy. • Fiber scintillation and silicon strip detectors were tested with heavy ion beams. • A new fiber scintillation detector showed an excellent position resolution. • Position and energy detection by silicon strip detectors enable full identification. -- Abstract: As next generation spectroscopic tools, heavy-ion cooler storage rings will be a unique application of highly charged RI beam experiments. Decay spectroscopy of highly charged rare isotopes provides us important information relevant to the stellar conditions, such as for the s- and r-process nucleosynthesis. In-ring decay products of highly charged RI will be momentum-analyzed and reach a position-sensitive detector set-up located outside of the storage orbit. To realize such in-ring decay experiments, we have developed and tested two types of high-resolution position-sensitive detectors: silicon strips and scintillating fibers. The beam test experiments resulted in excellent position resolutions for both detectors, which will be available for future storage-ring experiments.

  10. Ion-Induced Beam Instability in an Electron Storage Ring

    Institute of Scientific and Technical Information of China (English)

    LI Yong-Jun; JIN Yu-Ming; LI Wei-Min; LIU Zu-Ping

    2000-01-01

    In a small electron storage ring, such as the Hefei Light Source (HLS) ring, the newly generated ions, which can not escape from the beam potential and then are trapped from turn to turn, will lead to the beam instability. The ions created by the leading bunches can perturb the trailing bunches and also themselves during their subsequent passage, which will make the amplitude of beam oscillation be damped and anti-damped periodically. A computer simulation based on the strong-weak model shows a good agreement with our analytical model using the linear theory.

  11. Synchronization of Chaotic Storage-Ring Free-Electron Laser by Bi-Directional Coupling Scheme with the Coupling Strength Varied Periodically

    Institute of Scientific and Technical Information of China (English)

    HUANG Liang-Yu; LUO Xiao-Shu

    2006-01-01

    @@ We analyse the chaotic dynamics of storage-ring free-electron lasers and report a bi-directional coupled scheme with the coupling strength varied periodically to synchronize two chaotic storage-ring free-electron lasers.

  12. The KACST Heavy-Ion Electrostatic Storage Ring

    Science.gov (United States)

    Almuqhim, A. A.; Alshammari, S. M.; El Ghazaly, M. O. A.; Papash, A. I.; Welsch, C. P.

    2011-10-01

    A novel Electrostatic Storage Ring (ESR) for beams at energies up to 30keV/q is now being constructed at the National Centre for Mathematics and Physics (NCMP), King Abdul-Aziz City for Science and Technology (KACST). The ring is designed to be the core of a highly flexible experimental platform that will combine a large package of complementary beam techniques for atomic and molecular physics and related fields. The lattice design had to cover the different experimental techniques that the ring will be equipped with, such as e.g. Electron-Ion, Laser-Ion, Ion-Ion or Ion-Neutral beams, in both crossed and merged-beam configurations. The development of such an ESR is realized in a staged approach, in which a simple and early-run adaptation of the ring is built first, and then this basic version is upgraded to a higher symmetry of the ultimate version of the ring. Here, we report a general overview of this technical development with a focus on the layout of the first built stage of the ring.

  13. Stabilization of betatron tune in Indus-2 storage ring

    Science.gov (United States)

    Saroj, Jena; Yadav, S.; K. Agrawal, R.; D. Ghodke, A.; Pravin, Fatnani; A. Puntambekar, T.

    2014-06-01

    Indus-2 is a synchrotron radiation source that is operational at RRCAT, Indore, India. It is essentially pertinent in any synchrotron radiation facility to store the electron beam without beam loss. During the day to day operation of Indus-2 storage ring, difficulty was being faced in accumulating higher beam current. After examination, it was found that the working point was shifting from its desired value during accumulation. For smooth beam accumulation, a fixed desired tune in both horizontal and vertical plane plays a significant role in avoiding beam loss via the resonance process. This required a betatron tune feedback system to be put in the storage ring. After putting ON this feedback, the beam accumulation was smooth. The details of this feedback and its working principle are described in this paper.

  14. First commissioning of the HLS-II storage ring

    CERN Document Server

    Liu, Gang-Wen; Xu, Wei; Wang, Lin; Li, Wei-Min; Li, Jing-yi

    2015-01-01

    To meet the increasing requirements of synchrotron radiation users, the upgrade project to enhance the performance of Hefei Light Source (HLS), named HLS-II, was launched in 2010, and in 2014 the first commissioning of HLS-II was successfully completed. After the commissioning, the main design goals for the HLS-II storage ring have been achieved, with natural emittance of electron beam lower than 40 nm-rad at 800 MeV, five insertion devices installed in straight sections and root mean square (rms) jitter of closed orbit smaller than 4 {\\mu}m, making HLS-II at a higher level among the same class of machines in the world. This paper reports on the results of the commissioning of the HLS-II storage ring, which includes linear optics correction, compensation of insertion devices effect and closed orbit feedback.

  15. Storage Ring Measurements of Electron Impact Ionization for Solar Physics

    Science.gov (United States)

    Hahn, Michael; Becker, A.; Bernhardt, D.; Grieser, M.; Krantz, C.; Lestinsky, M.; Müller, A.; Novotný, O.; Repnow, R.; Schippers, S.; Spruck, K.; Wolf, A.; Savin, D. W.

    2013-07-01

    The interpretation of astrophysical spectra requires knowledge of the charge state distribution (CSD) of the plasma. The CSD is determined by the rates of ionization and recombination. Thus, accurate electron impact ionization (EII) data are needed to calculate the CSD of the solar atmosphere as well as for other electron-ionized astrophysical objects, such as stars, supernovae, galaxies, and clusters of galaxies. We are studying EII for astrophysically important ions using the TSR storage ring located at the Max Plank Institute for Nuclear Physics in Heidelberg, Germany. Storage ring measurements are largely free of the metastable contamination found in other experimental geometries, resulting in unambiguous EII data. We have found discrepancies of about 10% - 30% between our measured cross sections and those commonly used in CSD models. Because it is impractical to perform experimental measurements for every astrophysically relevant ion, theory must provide the bulk of the necessary EII data. These experimental results provide an essential benchmark for such EII calculations.

  16. Lattice study for the HLS-Ⅱ storage ring

    Institute of Scientific and Technical Information of China (English)

    BAI Zheng-He; WANG Lin; JIA Qi-Ka; LI Wei-Min

    2013-01-01

    The Hefei Light Source (HLS) is undergoing a major upgrade project,named HLS-Ⅱ,in order to obtain lower emittance and more insertion device straight sections.Undulators are the main insertion devices in the HLS-Ⅱstorage ring.In this paper,based on the database of lattice parameters built for the HLS-Ⅱ storage ring obtained by the global scan method,we use the quantity related to the undulator radiation brightness to more directly search for high brightness lattices.Lattice solutions for achromatic and non-achromatic modes are easily found with lower emittance,smaller beta functions at the center of the insertion device straight sections and lower dispersion in nonzero dispersion straight sections compared with the previous lattice solutions.In this paper,the superperiod lattice with alternating high and low horizontal beta functions in long straight sections for the achromatic mode is studied using the multiobjective particle swarm optimization algorithm.

  17. Scale Down Experiments for a Stellarator type Magnetostatic Storage Ring

    CERN Document Server

    Joshi, N; Meusel, O; Niebuhr, H; Ratzinger, U

    2016-01-01

    The beam transport experiments in toroidal magnets were first described in EPAC08 [1] within the framework of a proposed low energy ion storage ring at Frankfurt University. The experiments with two room temperature 30 degree toroids are needed to design the accumulator ring with closed longitudinal magnetic field levels up to 6-8 T. The test setup aims on developing a ring injection system. The primary beam line for the experiments was installed and successfully commissioned in 2009. A special probe for ion beam detection was installed. This modular technique allows online diagnostics of the ion beam along the beam path. In this paper, we present new results on beam transport experiments and discuss transport and transverse beam injection properties of that system.

  18. Cooler storage ring accomplished at heavy ion facility in Lanzhou

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Heavy Ion Research Facility in Lanzhou-Cooler Storage Ring (HIRFLCSR),a flagship facility of basic research in China,passed the acceptance check under auspices of the State Development and Reform Commission on 30 July in Lanzhou,capital of Gansu Province.The event was jointly presided over by the Commission's Vice Minister ZHANG Xiaoqian and CAS Executive Vice President BAI Chunli.

  19. Application of Accelerators and Storage Rings: Accelerators in Medicine

    CERN Document Server

    Amaldi, U

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '11.3 Accelerators in Medicine' of the Chapter '11 Application of Accelerators and Storage Rings' with the content: 11.3 Accelerators in Medicine 11.3.1 Accelerators and Radiopharmaceuticals 11.3.2 Accelerators and Cancer Therapy

  20. Bunch lengthening with bifurcation in electron storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun-San; Hirata, Kohji [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

    1996-08-01

    The mapping which shows equilibrium particle distribution in synchrotron phase space for electron storage rings is discussed with respect to some localized constant wake function based on the Gaussian approximation. This mapping shows multi-periodic states as well as double bifurcation in dynamical states of the equilibrium bunch length. When moving around parameter space, the system shows a transition/bifurcation which is not always reversible. These results derived by mapping are confirmed by multiparticle tracking. (author)

  1. Physics of Superpulses in Storage Ring Free-Electron Lasers

    Directory of Open Access Journals (Sweden)

    Vladimir N. Litvinenko

    2008-01-01

    Full Text Available Contradictory to the widespread perception, storage ring free-electron lasers with substantial net gain can generate peak lasing power reaching GW levels in the so-called superpulse mode. This power level is sufficient for studies of nonlinear processes and efficient intracavity harmonic generation. This letter describes the physics of the superpulses and a phase-space refreshment in the electron beam responsible for this phenomenon.

  2. 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.

  3. General spin precession and betatron oscillation in storage rings

    Science.gov (United States)

    Fukuyama, Takeshi

    2016-07-01

    Spin precession of particles having both anomalous magnetic and electric dipole moments (EDMs) is considered. We give the generalized expression of spin precession of these particles injected with transversal extent in magnetic storage rings. This is the generalization of the Farley’s pitch correction [F. J. N. Farley, Phys. Lett. B 42, 66 (1972)], including radial oscillation as well as vertical one. The transversal betatron oscillation formulae of these particles are also reproduced.

  4. Compensation for booster leakage field in the Duke storage ring

    Science.gov (United States)

    Li, Wei; Hao, Hao; Mikhailov, Stepan F.; Popov, Victor; Li, Wei-Min; Wu, Ying. K.

    2017-01-01

    The High Intensity Gamma-ray Source (HIGS) at Duke University is an accelerator-driven Compton gamma-ray source, providing high flux gamma-ray beam from 1 MeV to 100 MeV for photo-nuclear physics research. The HIGS facility operates three accelerators, a linac pre-injector (0.16 GeV), a booster injector (0.16—1.2 GeV), and an electron storage ring (0.24—1.2 GeV). Because of the proximity of the booster injector to the storage ring, the magnetic field of the booster dipoles close to the ring can significantly alter the closed orbit in the storage ring being operated in the low energy region. This type of orbit distortion can be a problem for certain precision experiments which demand a high degree of energy consistency of the gamma-ray beam. This energy consistency can be achieved by maintaining consistent aiming of the gamma-ray beam, and therefore a steady electron beam orbit and angle at the Compton collision point. To overcome the booster leakage field problem, we have developed an orbit compensation scheme. This scheme is developed using two fast orbit correctors and implemented as a feedforward which is operated transparently together with the slow orbit feedback system. In this paper, we will describe the development of this leakage field compensation scheme, and report the measurement results, which demonstrate the effectiveness of the scheme. Supported by National Natural Science Foundation of China (11175180, 11475167) and US DOE (DE-FG02-97ER41033)

  5. Future Synchrotron Light Sources Based on Ultimate Storage Rings

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yunhai; /SLAC

    2012-04-09

    The main purpose of this talk is to describe how far one might push the state of the art in storage ring design. The talk will start with an overview of the latest developments and advances in the design of synchrotron light sources based on the concept of an 'ultimate' storage ring. The review will establish how bright a ring based light source might be, where the frontier of technological challenges are, and what the limits of accelerator physics are. Emphasis will be given to possible improvements in accelerator design and developments in technology toward the goal of achieving an ultimate storage ring. An ultimate storage ring (USR), defined as an electron ring-based light source having an emittance in both transverse planes at the diffraction limit for the range of X-ray wavelengths of interest for a scientific community, would provide very high brightness photons having high transverse coherence that would extend the capabilities of X-ray imaging and probe techniques beyond today's performance. It would be a cost-effective, high-coherence 4th generation light source, competitive with one based on energy recovery linac (ERL) technology, serving a large number of users studying material, chemical, and biological sciences. Furthermore, because of the experience accumulated over many decades of ring operation, it would have the great advantage of stability and reliability. In this paper we consider the design of an USR having 10-pm-rad emittance. It is a tremendous challenge to design a storage ring having such an extremely low emittance, a factor of 100 smaller than those in existing light sources, especially such that it has adequate dynamic aperture and beam lifetime. In many ultra-low emittance designs, the injection acceptances are not large enough for accumulation of the electron beam, necessitating on-axis injection where stored electron bunches are completely replaced with newly injected ones. Recently, starting with the MAX-IV 7-bend

  6. Cooler Storage Ring at China Institute of Modern Physics

    CERN Document Server

    Wen-Xia, Jia; Zhan, W

    2005-01-01

    CSR, a new ion cooler-storage-ring project in China IMP, is a double ring system, and consists of a main ring (CSRm) and an experimental ring (CSRe). The two existing cyclotrons SFC (K=69) and SSC (K=450) of the Heavy Ion Research Facility in Lanzhou (HIRFL) will be used as its injector system. The heavy ion beams with the energy range of 7-30 MeV/nucleus from the HIRFL will be accumulated, cooled and accelerated to the higher energy range of 100-500 MeV/ nucleus in CSRm, and then extracted fast to produce radioactive ion beams or highly charged heavy ions. Those secondary beams will be accepted and stored or decelerated by CSRe for many internal-target experiments or high precision spectroscopy with beam cooling. On the other hand, the beams with the energy range of 100-1000MeV/ nucleus will also be extracted from CSRm by using slow extraction or fast extraction for many external-target experiments. CSR project was started in the end of 1999 and will be finished in 2006. In this paper the outline and the act...

  7. Beam Loss Monitors for NSLS-II Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, S.L.; Cameron, P.

    2011-03-28

    The shielding for the NSLS-II storage ring will provide adequate protection for the full injected beam losses in two cells of the ring around the injection point, but the remainder of the ring is shielded for lower losses of <10% top-off injection beam current. This will require a system to insure that beam losses do not exceed levels for a period of time that could cause excessive radiation exposure outside the shield walls. This beam Loss Control and Monitoring system will have beam loss monitors that will measure where the beam charge is lost around the ring, to warn operators if losses approach the design limits. To measure the charge loss quantitatively, we propose measuring the electron component of the shower as beam electrons hit the vacuum chamber (VC) wall. This will be done using the Cerenkov light as electrons transit ultra-pure fused silica rods placed close to the inner edge of the VC. The entire length of the rod will collect light from the electrons of the spread out shower resulting from the small glancing angle of the lost beam particles to the VC wall. The design and measurements results of the prototype Cerenkov BLM will be presented.

  8. Fast cooling of bunches in compton storage rings*

    CERN Document Server

    Bulyak, E; Zimmermann, F

    2011-01-01

    We propose an enhancement of laser radiative cooling by utilizing laser pulses of small spatial and temporal dimensions, which interact only with a fraction of an electron bunch circulating in a storage ring. We studied the dynamics of such electron bunch when laser photons scatter off the electrons at a collision point placed in a section with nonzero dispersion. In this case of ‘asymmetric cooling’, the stationary energy spread is much smaller than under conditions of regular scattering where the laser spot size is larger than the electron beam; and the synchrotron oscillations are damped faster. Coherent oscillations of large amplitude may be damped within one synchrotron period, so that this method can support the rapid successive injection of many bunches in longitudinal phase space for stacking purposes. Results of extensive simulations are presented for the performance optimization of Compton gamma-ray sources and damping rings.

  9. Measurement of sextupole orbit offsets in the APS storage ring.

    Energy Technology Data Exchange (ETDEWEB)

    Borland, M.

    1999-04-16

    Horizontal orbit errors at the sextuples in the Advanced Photon Source (APS) storage ring can cause changes in tune and modulation of the beta functions around the ring. To determine the significance of these effects requires knowing the orbit relative to the magnetic center of the sextuples. The method considered here to determine the horizontal beam position in a given sextupole is to measure the tune shift caused by a change in the sextupole strength. The tune shift and a beta function for the same plane uniquely determine the horizontal beam position in the sextupole. The beta function at the sextupole was determined by propagating the beta functions measured at nearby quadrupoles to the sextupole location. This method was used to measure the sextupole magnetic center offset relative to an adjacent beam position monitor (BPM) at a number of sextupole locations. We report on the successes and problems of the method as well as an improved method.

  10. ELASR – An electrostatic storage ring for atomic and molecular physics at KACST

    Directory of Open Access Journals (Sweden)

    Mohamed O.A. El Ghazaly

    2015-01-01

    Full Text Available A new ELectrostAtic Storage Ring (ELASR has been designed and built at the King Abdulaziz City for Science and Technology (KACST, in Riyadh, Saudi Arabia. It was developed to be the core of a new storage ring laboratory for atomic and molecular physics at KACST. ELASR follows the standard design of the pioneering storage ring ELISA and it thereby features a racetrack single-bend shaped ring. Complementary simulation code packages were used to work out the design under the requirements of the projected experiments. This paper reports a short description of the ELASR storage ring through an overview of its design and construction.

  11. The injection septum magnets of the SPring-8 storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Keiko; Matsui, Sakuo [JAERI-RIKEN, Hyogo (Japan)

    1994-07-01

    Three DC septum magnets and a pulsed septum magnet are used for the injection of the SPring-8 storage ring. This paper describes the design principle of these injection septum magnets and the electromagnetic performances of a prototype pulsed magnet. The peak strength of the magnetic stray field of the pulsed septum magnet is 1.3 gauss on the bump orbit, and is lower than the limit of sensitivity of the measurement on the reference orbit when the field strength in the magnet gap is 5,600 gauss and the pulse width is 65 {mu}sec.

  12. Beam loss studies at the ANKA storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Hertle, Edmund; Smale, Nigel; Goetsch, Tobias; Mueller, Anke-Susanne; Wegh, Frans; Worms, Kai [Karlsruher Institut fuer Technologie (Germany)

    2013-07-01

    The real time study and the post mortem analysis of beam loss are powerful tools for the optimization of a storage ring's performance. It allows, for example, a fast identification of failing hardware components or can be used to improve the beam lifetime by a reduction of the losses. This needs a sophisticated beam loss monitor system with appropriate spatial and temporal resolution. This presentation gives an overview of the loss monitor system under study at the ANKA synchrotron radiation facility of the Karlsruhe Institute of Technology.

  13. Design and manufacturing of the antechamber for BEPCII storage rings

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Antechamber which composes the arc vacuum chamber of storage rings is one of the key devices of BEPCII. It has the characteristic of various specifications, large size, complex structure, and high dimension accuracy. This paper gives a review on the structure features and the procedure of production, including the mechanical machining process, cleaning and welding process of high vacuum aluminum alloy, ultrahigh vacuum test and so on. In view of the occurrence of the concave deformation, the reasons are analyzed and the correction method developed is introduced too.

  14. Radiation Damage of Polypropylene Fiber Targets in Storage Rings

    CERN Document Server

    Rohdjess, H; Bisplinghoff, J; Bollmann, R; Büsser, K; Diehl, O; Dohrmann, F; Engelhardt, H P; Eversheim, P D; Greiff, J; Gross, A; Gross-Hardt, R; Hinterberger, F; Igelbrink, M; Langkau, R; Maier, R; Mosel, F; Müller, M; Muenstermann, M; Prasuhn, D; Von Rossen, P; Scheid, H; Schirm, N; Schwandt, F; Scobel, W; Trelle, H J; Wellinghausen, A; Wiedmann, W; Woller, K; Ziegler, R

    2004-01-01

    Thin polypropylene (CH$_2$) fibers have been used for internal experiments in storage rings as an option for hydrogen targets. The change of the hydrogen content due to the radiation dose applied by the circulating proton beam has been investigated in the range $1\\cdot10^6$ to $2\\cdot10^8$~Gy at beam momenta of 1.5 to 3 GeV/c by comparing the elastic pp-scattering yield to that from inelastic p-carbon reactions. It is found that the loss of hydrogen as a function of applied dose receives contributions from a fast and a slow component.

  15. Study of orbit stability in the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    DAI Zhi-Min; LIU Gui-Min; HUANG Nan

    2003-01-01

    In this paper, analysis of the beam orbit stability and conceptual study of the dynamic orbit feedback inthe SSRF storage ring are presented. It is shown that beam orbit position movement at the photon source points issmaller than the orbit stability requirements in horizontal plane, but exceeds the orbit stability requirements in verticalplane. A dynamic global orbit feedback system, which consists of 38 high-bandwidth air-coil correctors and 40high-precise BPMs, is proposed to suppress the vertical beam orbit position movement. Numerical simulations showthat this dynamic orbit feedback system can stabilize the vertical beam orbit position movement in the frequencyrange up to 100 Hz.

  16. Application of permanent magnets in accelerators and electron storage rings

    Science.gov (United States)

    Halbach, K.

    1985-04-01

    The use of permanent-magnet systems in high-energy accelerators and as sources of synchrotron radiation in electron-storage rings is discussed in a review of recent experimental investigations. Consideration is given to the generic advantages of permanent magnets over electromagnets (higher field strength per magnet size) in small-scale configurations; the magnetic properties of some charge-sheet-equivalent-permanent-magnet materials (CSEMs); and the design of pure-CSEM and CSEM-Fe-hybrid multipole magnetic lenses, dipoles, and undulator/wiggler systems for use in free-electron lasers and the production of elliptically polarized synchrotron light. Drawings and diagrams are provided.

  17. Measurement of electric dipole moments at storage rings

    Science.gov (United States)

    Jörg Pretz JEDI Collaboration

    2015-11-01

    The electric dipole moment (EDM) is a fundamental property of a particle, like mass, charge and magnetic moment. What makes this property in particular interesting is the fact that a fundamental particle can only acquire an EDM via {P} and {T} violating processes. EDM measurements contribute to the understanding of the matter over anti-matter dominance in the universe, a question closely related to the violation of fundamental symmetries. Up to now measurements of EDMs have concentrated on neutral particles. Charged particle EDMs can be measured at storage ring. Plans at Forschungszentrum Jülich and results of first test measurements at the COoler SYnchrotron COSY will be presented.

  18. Octupole Focusing Relativistic Self-Magnetometer Electric Storage Ring "Bottle"

    CERN Document Server

    Talman, Richard

    2015-01-01

    A method proposed for measuring the electric dipole moment (EDM) of a charged fundamental particle such as the proton, is to measure the spin precession caused by a radial electric bend field $E_r$, acting on the EDMs of frozen spin polarized protons circulating in an all-electric storage ring. The dominant systematic error limiting such a measurement comes from spurious spin precession caused by unintentional and unknown average radial magnetic field $B_r$ acting on the (vastly larger) magnetic dipole moments (MDM) of the protons. Along with taking extreme magnetic shielding measures, the best protection against this systematic error is to use the storage ring itself, as a "self-magnetometer"; the exact magnetic field average $\\langle B_r\\rangle$ that produces systematic EDM error, is nulled to exquisite precision by orbit position control. By using octupole rather than quadrupole focusing the restoring force can be vanishingly small for small amplitude vertical betatron-like motion yet strong enough at larg...

  19. CESAR, 2 MeV electron storage ring; general view.

    CERN Multimedia

    1964-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  20. Beam based alignment of the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    ZHANG Man-Zhou; LI Hao-Hu; JIANG Bo-Cheng; LIU Gui-Min; LI De-Ming

    2009-01-01

    There are 140 beam position monitors (BPMs) in the Shanghai Synchrotron Radiation Facility (SSRF) storage ring used for measuring the closed orbit. As the BPM pickup electrodes are assembled directly on the vacuum chamber, it is important to calibrate the electrical center offset of the BPM to an adjacent quadrupole magnetic center. A beam based alignment (BBA) method which varies individual quadrupole magnet strength and observes its effects on the orbit is used to measure the BPM offsets in both the horizontal and vertical planes. It is a completely automated technique with various data processing methods. There are several parameters such as the strength change of the correctors and the quadrupoles which should be chosen carefully in real measurement. After several rounds of BBA measurement and closed orbit correction, these offsets are set to an accuracy better than 10 μm. In this paper we present the method of beam based calibration of BPMs, the experimental results of the SSRF storage ring, and the error analysis.

  1. CESAR, 2 MeV electron storage ring.

    CERN Multimedia

    1967-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  2. STRIPLINE KICKER DESIGN FOR NSLS2 STORAGE RING

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, W.; Blednykh, A.; Krinsky, S.; Singh, O.

    2011-03-28

    In the NSLS2 storage ring, there are four stripline kickers/pickups. Two long striplines with electrode length of 30cm will be used as bunch-by-bunch transverse feedback actuators. Two short stripline kickers/pickups with 15cm length will mainly used for tune measurement excitation or signal pickup for the beam stability monitor. High shunt impedance of the long stripline kickers is demanded to produce 200 {micro}s damping time. Meanwhile the beam impedance should be minimized. The design work for these two types of stripline is discussed in this paper. NSLS2 is a third-generation light source under construction at Brookhaven National Laboratory. The machine will have < 1nm.rad horizontal emittance by using weak dipoles together with damping wigglers. For the storage ring of 792m circumference, geometric impedance, resistive wall impedance and ion effects are expected to be significant. A transverse bunch-by-bunch feedback system has been designed to suppress the coupled bunch instabilities. More information can be found in previous paper.

  3. Ion beam polarization in storage rings. Production, controlling and preservation

    Energy Technology Data Exchange (ETDEWEB)

    Prozorov, A. [St. Petersburg State Univ. (Russian Federation). V.A. Fock Research Institute for Physics; Labzowsky, L. [St. Petersburg State Univ. (Russian Federation). V.A. Fock Research Institute for Physics]|[St. Petersburg Nuclear Physics Institute (Russian Federation); Plunien, G. [Technische Univ. Dresden (Germany). Inst. fuer Theoretische Physik; Liesen, D. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Heidelberg Univ. (Germany). Physikalisches Inst.; Bosch, F. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Fritzsche, S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Heidelberg Univ. (Germany). Physikalisches Inst.]|[Max-Planck Insitute of Nuclear Physics, Heidelberg (Germany); Surzhykov, A. [Max-Planck Insitute of Nuclear Physics, Heidelberg (Germany)

    2008-03-15

    The present paper reports on the actual status of the theoretical concepts for the production of polarized heavy ion beams in storage rings and for methods to control online the degree of polarization as well as investigations of the preservation of the polarization during the ion movement across the magnetic system of the ring. It is argued that for hydrogen-like ions beam polarization can be built up efficiently by optical pumping of the Zeeman sublevels of ground-state hyperfine levels and that the maximal achievable nuclear polarization exceeds 90%. Of special interest are polarized helium-like ions which can be produced by the capture of one electron, because in selected cases parity nonconservation effects are found to be of unprecedented size in Atomic Physics. The measurements of these effects require online-diagnostics of the degree of the ion beam polarization. It is shown that this can be accomplished by an online-detection of the linear polarization of the X-rays which are emitted with the capture of the electron. In order to investigate the preservation of the polarization of the ions stored in the ring, the concept of an instantaneous quantization axis is introduced. The dynamics of this axis and the behaviour of the polarization with respect to it are explored in detail. (orig.)

  4. Status and upgrade of the VEPP-4 storage-ring facility

    Science.gov (United States)

    Levichev, E. B.

    2016-12-01

    The VEPP-4 facility is an e + e - collider with a beam energy up to 2 GeV. The scientific program includes topics in high-energy and nuclear physics, as well as various investigations using synchrotron radiation and polarized or unpolarized charged-particle beams. An energy upgrade to 5 GeV is planned, and reliable and efficient operation of the storage-ring complex upon increased energy must be provided. We discuss the recent experimental results and the opportunities to be created by the energy upgrade.

  5. Coupling measurement and correction at the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Brightness is an important parameter for 3rd generation light source. Correcting the emittance coupling is a realistic way to increase brightness without any additional equipment in a machine under operation. The main sources of emittance coupling are betatron coupling and vertical dispersion. At the SSRF storage ring, tune split and LOCO are used to measure the respective betatron and emittance coupling. Both of these sources can be corrected by skew quadrupoles. By measuring the skew quadrupole-coupling response matrix, betatron coupling can be changed from 0.014% to 2%. But the vertical dispersion changes at the same time. LOCO can find the suitable setting to correct simultaneously the betatron coupling and vertical dispersion. The emittance coupling can be reduced to 0.17% by this method. More simulations show the potential for smaller emittance coupling if more skew quadrupoles are employed.

  6. Ion trapping in the high-energy storage ring HESR

    Energy Technology Data Exchange (ETDEWEB)

    Hinterberger, Frank [Bonn Univ. (Germany). Helmholtz-Institut fuer Strahlen- und Kernphysik

    2011-10-15

    The problem of ion trapping in the high-energy storage ring HESR is studied in the present report. Positive ions are trapped in the negative potential well of the antiproton beam. The ions are produced by the interaction between the antiproton beam and the residual gas. The adverse effects of ion trapping like tune shifts, tune spreads and coherent instabilities are reviewed. The ion production rate by ionization of the residual gas molecules is estimated. The negative potential well and the corresponding electric fields of the antiproton beam are evaluated in order to study the transverse and longitudinal motion of the ions and the accumulation in trapping pockets. The removal of ions can be achieved using clearing electrodes and under certain conditions resonant transverse beam shaking. Diagnostic tools and measurements of trapped ion effects are sketched. (orig.)

  7. Emittance growth induced by electron cloud in proton storage rings

    CERN Document Server

    Benedetto, Elena; Coppa, G

    2006-01-01

    In proton and positron storage rings with many closely spaced bunches, a large number of electrons can accumulate in the beam pipe due to various mechanisms (photoemission, residual gas ionization, beam-induced multipacting). The so-formed electron cloud interacts with the positively charged bunches, giving rise to instabilities, emittance growth and losses. This phenomenon has been observed in several existing machines such as the CERN Super Proton Synchrotron (SPS), whose operation has been constrained by the electron-cloud problem, and it is a concern for the Large Hadron Collider (LHC), under construction at CERN. The interaction between the beam and the electron cloud has features which cannot be fully taken into account by the conventional and known theories from accelerators and plasma physics. Computer simulations are indispensable for a proper prediction and understanding of the instability dynamics. The main feature which renders the beam-cloud interactions so peculiar is that the the electron cloud...

  8. Spin Motion and Resonances in Accelerators and Storage Rings

    Energy Technology Data Exchange (ETDEWEB)

    Courant,E.

    2008-01-01

    Some of the basic aspects of the spin dynamics of accelerators and storage rings are reviewed. Since the components of spin parallel and perpendicular to the particle velocity behave differently it is desirable to reformulate the equations of spin motion in a frame of reference that exhibits this difference explicitly. The conventional treatment employs a coordinate system derived from a reference orbit. An alternate coordinate system, based on the actual trajectory of the particle, leads to simplified equations of spin motion but, contrary to a conjecture presented in a previous note, resonance strengths calculated by the conventional and the revised formalisms are identical, as pointed out by Kondratenko. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

  9. 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.

  10. Performance of the OK-4/Duke storage ring FEL

    CERN Document Server

    Litvinenko, V N; Pinayev, I V; Wu, Y

    2001-01-01

    In this paper, we report measured parameters of the OK-4 FEL driven by the Duke storage ring. The OK-4 FEL was being operated continuously for 2 yr in the broad wavelength range for user applications utilising spontaneous and coherent XUV and UV radiation as well as Compton back-scattered gamma-rays in the range of 2-58 MeV. During this time, the OK-4 FEL lased in the range from 193.7 to about 730 nm using five sets of mirrors and electron beam energies from 240 to 800 MeV. Our predictions for the OK-4 FEL are compared with measured performance, both in the CW and in the giant pulse mode. We discuss our future plans for the OK-4 FEL operation as well as the construction and commissioning of the OK-5 FEL with helical wigglers.

  11. EDM searches at storage rings with Wien filters

    Energy Technology Data Exchange (ETDEWEB)

    Saleev, Artem [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik; Nikolaev, Kolya [Landau Institute, Chernogolovka (Russian Federation); Collaboration: JEDI-Collaboration

    2013-07-01

    Future searches of an EDM of protons and deuterons at COSY storage ring in Juelich, envision the use of Wien filter acting as spin rotator. Crucial idea is that Wien filter produces spin kicks which give a growth of the EDM signal. In all approaches one starts with the injection of the vertically polarized beam. Radiofrequency Wien filter modulates spin tune of stored particles. If EDM is non-zero this modulation conspires with the EDM-induced rotation of the spin in the motional electric field in the ring and generates the EDM signal - the in-plane horizontal polarization. We discuss the duality between RF spin flipper and RF Wien filter and we argue why spin coherence time is equal for two devices. Another case is static Wien filter with constant fields. Behavior of spin vector is the same, but the machine is operated exactly at imperfection resonance (for protons, Gγ=2), which drastically decreases spin coherence time. Last case is more promising but it needs supercompensated magnetic lattice, an option which has to be studied further.

  12. Proceedings of the workshop on polarized targets in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Holt, R.J. (ed.)

    1984-08-01

    Polarization phenomena have played an increasingly important part in the study of nuclei and nucleons in recent years. Polarization studies have been hampered by the relatively few and rather fragile polarized targets which are presently available. The concept of polarized gas targets in storage rings opens a much wider range of possibilities than is available in the external target geometry. This novel method will represent a considerable advance in nuclear physics and will continue to receive much attention in plans for future facilities. An internal, polarized-target station is being planned for the cooler ring at the Indiana University Cyclotron Facility. Internal targets are compatible with recent designs of electron accelerators proposed by the Massachusetts Institute of Technology and the Southeastern Universities Research Association. The key to nuclear-science programs based on internal targets pivots on recent developments in polarized atomic beam methods, which include the more recent laser-driven polarized targets. The workshop drew together a unique group of physicists in the fields of high-energy, nuclear and atomic physics. The meeting was organized in a manner that stimulated discussion among the 58 participants and focused on developments in polarized target technology and the underlying atomic physics. An impressive array of future possibilities for polarized targets as well as current developments in polarized target technology were discussed at the workshop. Abstracts of individual items from the workshop were prepared separately for the data base.

  13. Numerical simulation of crystalline ion beams in storage ring

    Science.gov (United States)

    Meshkov, I.; Möhl, D.; Katayama, T.; Sidorin, A.; Smirnov, A.; Syresin, E.; Trubnikov, G.; Tsutsui, H.

    2004-10-01

    The use of crystalline ion beams can increase luminosity in the collider and in experiments with targets for investigation of rare radioactive isotopes. The ordered state of circulating ion beams was observed at several storage rings: NAP-M (Proceedings of the Fourth All Union Conference on Charged Particle Accelerators, Vol. 2, Nauka, Moscow, 1975 (in Russian); Part. Accel. 7 (1976) 197; At. Energy 40 (1976) 49; Preprint CERN/PS/AA 79-41, Geneva, 1979) (Novosibirsk), ESR (Phys. Rev. Lett. 77 (1996) 3803) and SIS (Proceedings of EPAC'2000, 2000) (Darmstadt), CRYRING (Proceedings of PAC'2001, 2001) (Stockholm) and PALLAS (Proceedings of the Conference on Applications of Accelerators in Research and Industry, AIP Conference Proceedings, p. 576, in preparation) (München). New criteria of the beam orderliness are derived and verified with a new program code. Molecular dynamics technique is inserted in BETACOOL program (Proceedings of Beam Cooling and Related Topics, Bad Honnef, Germany, 2001) and used for numerical simulation of crystalline beams. The sudden reduction of momentum spread in the ESR experiment is described with this code. The simulation shows a good agreement with the experimental results. The code has then been used to calculate characteristics of the ordered state of ion beams for the MUSES Ion Ring (IR) (MUSES Conceptual Design Report, RIKEN, Japan, 2001) in collider mode. A new strategy of the cooling process is proposed which permits to increase significantly the linear density of the ordered ion beam and thereby the luminosity of electron-ion colliding experiments.

  14. Analytical solutions for spin response functions in model storage rings with Siberian Snakes

    Energy Technology Data Exchange (ETDEWEB)

    Mane, S.R. [Convergent Computing Inc., P.O. Box 561, Shoreham, NY 11786 (United States)], E-mail: srmane@optonline.net

    2009-03-01

    I present analytical solutions for the spin response functions for radial field rf dipole spin flippers in models of storage rings with one Siberian Snake or two diametrically opposed orthogonal Siberian Snakes. The solutions can serve as benchmarks tests for computer programs. The spin response functions can be used to calculate the resonance strengths for radial field rf dipole spin flippers in storage rings.

  15. New Results from Experiments at the HERA Storage Ring and from ARGUS

    Science.gov (United States)

    Wegener, D.

    1994-10-01

    Recent results from the ep storage ring HERA and from the e+e- storage ring DORIS II are discussed. Special emphasis is given to the specific layout of the detectors and to the progress in calorimetry achieved in the last few years. The impact of the ARGUS experiment on B- and π-physics is discussed.

  16. Coherent Harmonic Generation using the Elettra Storage-Ring Optical Klystron A Numerical Analysis

    CERN Document Server

    Curbis, F

    2005-01-01

    Coherent harmonic generation can be obtained by means of frequency up-conversion of a high-power external laser focused into the first undulator of an optical klystron. The standard configuration is based on a single-pass device, where the seed laser is synchronized with an electron beam entering the first undulator of the optical klystron after being accelerated using a linear accelerator. As an alternative, the optical klystron may be installed on a storage ring, where it is normally used as interaction region for an oscillator free-electron laser. In this case, removing the optical cavity and using an external seed, one obtains a configuration which is similar to the standard one but also presents some peculiar characteristics. In this paper we investigate the possibility of harmonic generation using the Elettra storage-ring optical klystron. We explore different experimental set-ups varying the beam energy, the seed characteristics and the strength of the optical-klystron dispersive section. We also study...

  17. Commissioning of the Cryogenic Plant for the Cryogenic Storage Ring (CSR) at Heidelberg

    CERN Document Server

    von Hahn, R; Grieser, M; Haberstroh, C; Kaiser, D; Lange, M; Laux, F; Menk, S; Orlov, D A; Repnow, R; Sieber, T; Quack, H; Varju, J; Wolf A

    2009-01-01

    At the Max-Planck-Institute for Nuclear Physics in Heidelberg a next generation electrostatic storage ring for low velocity atomic and molecular ion beams is under construction. In contrast to existing electrostatic storage rings, the Cryogenic Storage Ring CSR will be cooled down to temperatures below 2 K. Thus acting as a large cryopump it will provide long storage times and, in addition, open a new field of quantum state controlled molecular physics due to a low heat radiation background from space-like environment. A concept for cooling the storage ring has been developed and is presently tested by means of a linear trap as a prototype with a length of 1/10 of the planned ring. A commercial refrigerator with 21 W at 2 K has been successfully commissioned and was connected to the prototype. This paper presents the status of the cryogenic plant after the commissioning and one year of operation.

  18. QCD physics at hadron storage rings: From COSY to FAIR

    Indian Academy of Sciences (India)

    James Ritman

    2006-05-01

    As a result of the rapid rise of the coupling constant at low momentum transfers, perturbation theory is not an appropriate method to describe the strong interaction. In this kinematic regime other methods such as lattice QCD or effective field theories are more appropriate to investigate the appearance of a still unsettled phenomena: confinement and chiral symmetry breaking. Furthermore, the confinement of quarks and gluons to hadrons allows crucial tests of fundamental symmetries that are inherent to the QCD Lagrangian but are broken in hadronic systems. Thus, high precision measurements of the production and decay of specific hadronic states provides decisive benchmarks to investigate the properties of QCD in this regime. A new series of experiments are being prepared using nearly full acceptance detectors for neutral and charged particles around internal targets in high intensity, phase-space-cooled hadronic beams. Later this year, it is planned to transfer the WASA detector from the CELSIUS to the COSY ring in order to measure the production and various decay channels of the and ' mesons, thereby investigating the violation of P, C, T, and combinations thereof, as well as isospin violation. The experimental and theoretical techniques employed here will provide an important basis to extend these investigations to the static and dynamical properties of hadrons with charm quark content with the high energy storage ring for antiprotons at the new GSI/FAIR facility. Additional related perspectives will be opened at the new facility ranging from the properties of hadrons in dense nuclear matter to measurements of the nucleon's transverse spin distribution in the valence quark region using polarized antiprotons.

  19. Historic moment as SESAME begins storage ring installation

    CERN Multimedia

    JORDAN

    2016-01-01

    The first of the 16 cells of SESAME (link is external)’s storage ring was installed recently in the shielding tunnel in the Centre’s experimental hall in Allan, Jordan. SESAME will be the Middle East’s first synchrotron light source. The installation was led by SESAME’s Technical Director, Erhard Huttel, with help from members of CERN forming part of the CESSAMag (CERN-EC Support for SESAME Magnets) team as well as scientists and technicians from the SESAME region. Each cell consists of magnets (dipole, quadrupoles and sextupoles) and the vacuum chamber, supported by a girder. After many years in the making, commissioning of SESAME is scheduled to begin in 2016, serving a growing community of some 300 scientists from the region. The initial research programme will cover topics as diverse as the search for new cancer drugs to the exploration of the regions shared cultural heritage. SESAME is also a pioneer in promoting international cooperation in the region. The laboratory is expected

  20. The electrostatic Cryogenic Storage Ring CSR - Mechanical concept and realization

    Science.gov (United States)

    von Hahn, R.; Berg, F.; Blaum, K.; Crespo Lopez-Urrutia, J. R.; Fellenberger, F.; Froese, M.; Grieser, M.; Krantz, C.; Kühnel, K.-U.; Lange, M.; Menk, S.; Laux, F.; Orlov, D. A.; Repnow, R.; Schröter, C. D.; Shornikov, A.; Sieber, T.; Ullrich, J.; Wolf, A.; Rappaport, M.; Zajfman, D.

    2011-12-01

    A new and technologically challenging project, the electrostatic Cryogenic Storage Ring CSR, is presently under construction at the Max-Planck-Institute for Nuclear Physics in Heidelberg. Applying liquid helium cooling, the CSR, with 35 m circumference, will provide a low temperature environment of only a few Kelvin and an extremely high vacuum of better than 10 -13 mbar. To realize these conditions the mechanical design has been completed and now the first quarter section is in the construction phase. For the onion skin structure of the cryogenic system we have at the outer shell the cryostat chambers, realized by welded rectangular stainless steel frames with aluminum plates. The next two shells are fabricated as aluminum shields kept at 80 and 40 K. The inner vacuum chambers for the experimental vacuum consist of stainless steel chambers cladded with external copper sheets connected to the LHe lines for optimized thermal equilibration and cryopumping. Additional large surface 2 K units are installed for cryogenic pumping of H 2. The mechanical concepts and the realization will be presented in detail.

  1. Long-term stability of the APS storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Friedsam, H.; Penicka, M.; Error, J.

    1999-10-26

    The Advanced Photon Source (APS), a third-generation synchrotrons light source, was commissioned in 1995 at Argonne ''National Laboratory and has been fully-operational for beamline users since 1997. The APS storage ring can accommodate up to 68 user beamlines; about 70% of the available beamlines are currently in use by various collaborative access teams (CATS). The 7-GeV synchrotrons light source produces light in the soft to hard x-ray range that is used for research in such areas as x-ray instrumentation; material, chemical and atomic sciences; biology; and geo/soil/ environmental sciences. For the successful operation of an x-ray light source such as the Advanced Photon Source, the long-term stability of the concrete floor supporting the beam components and user beamlines is crucial. Settlements impact the orbit and location of the x-ray source points as well as the position of the x-ray beamlines. This paper compares the results of two successive resurveys of the APS accelerator components performed in 1995 and 1998.

  2. Design of the muon collider isochronous storage ring lattice

    Science.gov (United States)

    Trbojevic, D.; Ng, K. Y.; Courant, E. D.; Lee, S. Y.; Johnstone, C.; Gallardo, J.; Palmer, R.; Tepikian, S.

    1996-04-01

    The muon collider would extend the limitations of e+ e- colliders and provide new physics potentials, with possible discovery of the heavy Higgs bosons. At the maximum energy of 2 TeV the projected luminosity is of the order of 1035 cm-2 s-1. The colliding μ+ μ- bunches have to be focused to a very small transverse size of 2.8 μm, which is accomplished by the betatron functions at the crossing point of β*=3 mm. This requires a longitudinal space of the same length, 3 mm. These very short bunches at 2 TeV could circulate only in a quasi-isochronous storage ring where the momentum compaction is very close to zero. We report on a design of a muon collider isochronous lattice. The momentum compaction is brought to zero by having the average value of the dispersion function through dipoles equal to zero. This is accomplished by a combination of FODO cells with a low-beta insertion. The dispersion function oscillates between negative and positive values.

  3. Effects of insertion device on SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Shanghai Synchrotron Radiation Facility (SSRF), one of the third generation light sources, aims to produce high brightness and/or high flux X-ray source for users; therefore insertion devices (IDs) are important magnetic elements for SSRF. In this paper, the linear perturbations due to IDs toward its storage ring lattice, such as beta function distortions, tune shifts, emittance growths, and energy spreads are estimated by using analytical formulae, and the nonlinear effects from IDs, especially dynamic aperture, are simulated by using Racetrack code. The results show that (a) the reduction of dynamic aperture from single undulator is negligible, since electron beam energy of 3.5 GeV is high and ID's magnetic field is low, and the beta functions in the middle of straight sections, where ID is located, are well optimized; (b) however, the reduction from single wigglers, especially super-conducting wiggler, is visible, because of its higher magnetic field; (c) effects of each ID on emittance growths and energy spreads are less than 7%.

  4. Initial scientific uses of coherent synchrotron radiation inelectron storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Basov, D.N.; Feikes, J.; Fried, D.; Holldack, K.; Hubers, H.W.; Kuske, P.; Martin, M.C.; Pavlov, S.G.; Schade, U.; Singley, E.J.; Wustefeld, G.

    2004-11-23

    The production of stable, high power, coherent synchrotron radiation at sub-terahertz frequency at the electron storage ring BESSY opens a new region in the electromagnetic spectrum to explore physical properties of materials. Just as conventional synchrotron radiation has been a boon to x-ray science, coherent synchrotron radiation may lead to many new innovations and discoveries in THz physics. With this new accelerator-based radiation source we have been able to extend traditional infrared measurements down into the experimentally poorly accessible sub-THz frequency range. The feasibility of using the coherent synchrotron radiation in scientific applications was demonstrated in a series of experiments: We investigated shallow single acceptor transitions in stressed and unstressed Ge:Ga by means of photoconductance measurements below 1 THz. We have directly measured the Josephson plasma resonance in optimally doped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} for the first time and finally we succeeded to confine the sub-THz radiation for spectral near-field imaging on biological samples such as leaves and human teeth.

  5. Planning and Prototyping for a Storage Ring Measurement of the Proton Electric Dipole Moment

    Energy Technology Data Exchange (ETDEWEB)

    Talman, Richard [Cornell Univ., Ithaca, NY (United States)

    2015-07-01

    Electron and proton EDM's can be measured in "frozen spin" (with the beam polarization always parallel to the orbit, for example) storage rings. For electrons the "magic" kinetic energy at which the beam can be frozen is 14.5 MeV. For protons the magic kinetic energy is 230 MeV. The currently measured upper limit for the electron EDM is much smaller than the proton EDM upper limit, which is very poorly known. Nevertheless, because the storage ring will be an order of magnitude cheaper, a sensible plan is to first build an all-electric electron storage ring as a prototype. Such an electron ring was successfully built at Brookhaven, in 1954, as a prototype for their AGS ring. This leaves little uncertainty concerning the cost and performance of such a ring. (This is documentedin one of the Physical Review papers mentioned above.)

  6. Storage-ring ionization and recombination experiments with multiply charged ions relevant to astrophysical and fusion plasmas

    CERN Document Server

    Schippers, Stefan

    2011-01-01

    Past and ongoing research activities at the Heidelberg heavy-ion storage-ring TSR are reviewed which aim at providing accurate absolute rate coefficients and cross sections of atomic collision processes for applications in astrophysics and magnetically confined fusion. In particular, dielectronic recombination and electron impact ionization of iron ions are discussed as well as dielectronic recombination of tungsten ions.

  7. Users program for storage-ring based FEL and synchrotron sources of the Duke FEL Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Straub, K.D.; Barnett, G.; Burnham, B. [and others

    1995-12-31

    The storage ring at the Duke FEL Laboratory was first operated with a stored e-beam in November, 1994. It has now achieved operation energies in excess 1 GeV with more than 100 mA current at 280 MeV. The ring has several ports for FEL and synchrotron light source research. The circulating ring current can be synchronized with the seperate Mark III FEL operating in the 2-9.5 {mu}m IR region. This allows low optical jitter (10-20 ps) between the two sources and thus pump-probe operation. The ring has been configured to drive a number of light sources including the OK-4 FEL system capable of FEL operation between 400 and 65 nm, an inverse Compton scattering source using this undulator which will yield 4-200 MeV gammas, an undulator source at approximately 40 {angstrom} (not an FEL), a mm FEL with inverse compton scattering providing 1-100 keV x-rays and two synchrotron ports from the bend magnets for which the {lambda}{sub c} = 11-12 {angstrom} for 1 GeV. The broadly tunable FEL sources and their associated inverse compton scattering are extremely bright. The initial research proposals, submitted to the Laboratory emphasizes photoelectron spectroscopy, PEEM, high resolution vacuum UV of gases, solid spectroscopy and photochemistry in the UV, X-ray microprobe studies, X-ray microscopy, X-ray holography, X-ray crystallography, Mossbauer spectroscopy, nuclear spectroscopy, neutron production, photon activation therapy and broadband synchrotron as a probe of fast reaction in the IR and near IR.

  8. Analytical Approach to Eigen-Emittance Evolution in Storage Rings

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Boaz; /SLAC

    2006-05-16

    This dissertation develops the subject of beam evolution in storage rings with nearly uncoupled symplectic linear dynamics. Linear coupling and dissipative/diffusive processes are treated perturbatively. The beam distribution is assumed Gaussian and a function of the invariants. The development requires two pieces: the global invariants and the local stochastic processes which change the emittances, or averages of the invariants. A map based perturbation theory is described, providing explicit expressions for the invariants near each linear resonance, where small perturbations can have a large effect. Emittance evolution is determined by the damping and diffusion coefficients. The discussion is divided into the cases of uniform and non-uniform stochasticity, synchrotron radiation an example of the former and intrabeam scattering the latter. For the uniform case, the beam dynamics is captured by a global diffusion coefficient and damping decrement for each eigen-invariant. Explicit expressions for these quantities near coupling resonances are given. In many cases, they are simply related to the uncoupled values. Near a sum resonance, it is found that one of the damping decrements becomes negative, indicating an anti-damping instability. The formalism is applied to a number of examples, including synchrobetatron coupling caused by a crab cavity, a case of current interest where there is concern about operation near half integer {nu}{sub x}. In the non-uniform case, the moment evolution is computed directly, which is illustrated through the example of intrabeam scattering. Our approach to intrabeam scattering damping and diffusion has the advantage of not requiring a loosely-defined Coulomb Logarithm. It is found that in some situations there is a small difference between our results and the standard approaches such as Bjorken-Mtingwa, which is illustrated by comparison of the two approaches and with a measurement of Au evolution in RHIC. Finally, in combining IBS

  9. Ring wall storages. An essential contribution of the geotechnics to te energy storage; Ringwallspeicher. Ein essentieller Beitrag der Geotechnik zur Energiespeicherung

    Energy Technology Data Exchange (ETDEWEB)

    Popp, Matthias [Matthias Popp Ingenieurbuero Erneuerbare Energien, Energiespeicherung, Wuppertal (Germany)

    2012-11-01

    The author of the contribution under consideration reports on ring wall storages as an essential contribution to the geotechnical engineering for energy storage. At first, renewable energies as well as the storage requirements for the compensation of the volatility of electricity from wind power and solar energy are described. Subsequently, the storage technologies for energy management requirements as well as the need for water and land area of pumped storage systems are presented with special emphasis of ring wall storages.

  10. Theory and analysis of nonlinear dynamics and stability in storage rings: A working group summary

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, S.; Audy, P.; Courant, E.D.; Forest, E.; Guignard, G.; Hagel, J.; Heifets, S.; Keil, E.; Kheifets, S.; Mais, H.; Moshammer, H.; Pellegrini, C.; Pilat, F.; Suzuki, T.; Turchetti, G.; Warnock, R.L.

    1988-07-01

    A summary and commentary of the available theoretical and analytical tools and recent advances in the nonlinear dynamics, stability and aperture issues in storage rings are presented. 11 refs., 4 figs.

  11. ETEAPOT: symplectic orbit/spin tracking code for all-electric storage rings

    CERN Document Server

    Talman, Richard M

    2015-01-01

    Proposed methods for measuring the electric dipole moment (EDM) of the proton use an intense, polarized proton beam stored in an all-electric storage ring "trap". At the "magic" kinetic energy of 232.792 MeV, proton spins are "frozen", for example always parallel to the instantaneous particle momentum. This paper describes an accelerator simulation code, ETEAPOT, a new component of the Unified Accelerator Libraries (UAL), to be used for long term tracking of particle orbits and spins in electric bend accelerators, in order to simulate EDM storage ring experiments. Though qualitatively much like magnetic rings, the non-constant particle velocity in electric rings give them significantly different properties, especially in weak focusing rings. Like the earlier code TEAPOT (for magnetic ring simulation) this code performs \\emph{exact tracking in an idealized (approximate) lattice} rather than the more conventional approach, which is \\emph{approximate tracking in a more nearly exact lattice.} The BMT equation des...

  12. Response of Charged Particles in a Storage Ring to Gravitational Waves

    Institute of Scientific and Technical Information of China (English)

    DONG Dong; HUANG Chao-Guang

    2003-01-01

    The influence of gravitational waves on the charged particles in a storage ring is studied. It shows thatthe gravitational waves might be directly detected by monitoring the motion of charged particles in a storage ring. Theangular velocity of the charged particles is continually adjustable by changing the initial energy of particles and thestrength of the magnetic field. This feature is very useful for finding the gravitational waves with different frequencies.

  13. Response of Charged Particles in a Storage Ring to Gravitational Waves

    Institute of Scientific and Technical Information of China (English)

    DONGDong; HUANGChao-Guang

    2003-01-01

    The influence of gravitational waves on the charged particles in a storage ring is studied. It shows that the gravitational waves might be directly detected by monitoring the motion of charged particles in a storage ring. The angular velocity of the charged particles is continually adjustable by changing the initial energy of particles and the strength of the magnetic field. This feature is very useful for finding the gravitational waves with different frequencies.

  14. A practical method to generate brilliant hard x-rays with a tabletop electron storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H. [Ritsumeikan Univ., Shiga (Japan); Amano, D.; Miyade, H. [Sumitomo Heavy Industries, Ltd., Tanashi-City (Japan)

    1995-12-31

    With electron storage rings not only synchrotron radiation(SR) but also bremsstrahlung(BS) from a thin target placed in the electron orbit are mechanisms to generate brilliant x-ray beams. The calculated brilliance of BS with a 50 MeV storage ring, which is nearly 10{sup 13} photons/s, mrad{sup 2}, mm{sup 2}, 0.1% band width for 100 keV x-rays, exceeds that of SR from a 1 GeV storage ring. This photon energy spectrum is almost constant and extend up to the electron energy. The reasons for this high brilliance with this new radiation scheme is that the electron beams penetrating the thin target are utilized repeatedly, the narrow angular divergence of BS is determined by the kinematics of relativistic electron as same as SR, and the x-ray source size of the order of 1 {mu}m is determined by the size of thin target instead of electron beam sizes. Continuous injection of electron beam to the storage ring at full energy is the way to keep high and constant beam current. Peak current and repetition rate determine x-ray out put power. Note that the power of x-ray beam is also provided from a RF cavity of the storage ring. In this paper we will report some experimental results and discuss further application on a coherent bremsstrahlung generated from a set of stacked foils placed in the electron orbit of the ring. Resulting from these investigations the photon storage ring which is based on a 50 MeV exact circular electron storage ring could provide wide range of coherent and incoherent radiations from far infrared to hard x-ray in a practical amount of radiation power.

  15. A review of methods for experimentally determining linear optics in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Safranek, J.

    1995-12-31

    In order to maximize the brightness and provide sufficient dynamic aperture in synchrotron radiation storage rings, one must understand and control the linear optics. Control of the horizontal beta function and dispersion is important for minimizing the horizontal beam size. Control of the skew gradient distribution is important for minimizing the vertical size. In this paper, various methods for experimentally determining the optics in a storage ring will be reviewed. Recent work at the National Synchrotron Light Source X-Ray Ring will be presented as well as work done at laboratories worldwide.

  16. Storage life of silicone rubber sealing ring used in solid rocket motor

    Institute of Scientific and Technical Information of China (English)

    Liu Weikai; He Guoqiang

    2014-01-01

    It is urgent to carry out detailed research on storage performance of rubber sealing ring to get the criterion for its storage life. This paper acquires material ageing regularity by theoretical analysis and experimental confirmation. On this condition, failure mode and failure criterion of typ-ical sealing structure is studied, and the failure mechanism is found. Thus by analyzing the stress distribution, the relationship between ageing state and sealing condition is established. Rationaliza-tion proposal is put forward and storage life of sealing ring is evaluated. The research mentioned-above has special reference to the design of sealing structures and can provide reference for prolong-ing their service life.

  17. TSR: A storage and cooling ring for HIE-ISOLDE

    Energy Technology Data Exchange (ETDEWEB)

    Butler, P.A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Blaum, K. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Davinson, T. [School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom); Flanagan, K.; Freeman, S.J. [School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Grieser, M. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Lazarus, I.H. [S.T.F.C. Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Litvinov, Yu.A. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Lotay, G. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Page, R.D. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Raabe, R. [KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven (Belgium); Siesling, E.; Wenander, F. [CERN, 1211 Geneva 23 (Switzerland); Woods, P.J. [School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)

    2016-06-01

    It is planned to install the heavy-ion, low-energy ring TSR, currently at the Max-Planck-Institute for Nuclear Physics in Heidelberg, at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored, cooled secondary beams that is rich and varied, spanning from studies of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. In addition to experiments performed using beams recirculating within the ring, the cooled beams can be extracted and exploited by external spectrometers for high-precision measurements. The capabilities of the ring facility as well as some physics cases will be presented, together with a brief report on the status of the project.

  18. The new 1.5 GeV storage ring for synchrotron radiation: MAX II

    Science.gov (United States)

    Andersson, Å.; Eriksson, M.; Lindgren, L.-J.; Röjsel, P.; Werin, S.

    1995-02-01

    The MAX laboratory at Lund University, Sweden, today operates an accelerator system consisting of a 100 MeV racetrack microtron and a 550 MeV storage ring (MAX I). At the moment (July 1994) a new storage ring MAX II is near completion and will start first injections within 2 months. This work gives an overview of the MAX II project including the first beamlines and a description of the accelerator system. MAX II is a 1.5 GeV third generation light source optimized for the VUV and soft-x-ray region. It consists of a ten cell double bend achromat lattice forming the 90 m circumference ring. Injection is done at 500 MeV from the existing storage ring MAX I, and ramping up to full energy will take place in MAX II. The straight sections have a length of 3.2 m and eight sections are free to house insertion devices. At start up the ring will be equipped with one 7.5 T superconducting wiggler and one 1.8 T multipole wiggler. Two more undulators are ordered and under construction. To be able to achieve the project a few shortcuts have been made in the design of the storage ring: (1) Nonzero dispersion is allowed in the straight sections, (2) chromaticity correction is built into the quadrupole magnets, and (3) the length of the straight sections is limited to 3.2 m. The project is progressing on time. Extraction of an electron beam from the MAX I storage ring has been achieved and has successfully been transported into the MAX II building. The MAX II ring is under assembly with most of the sections already mounted. First injection is planned to take place in August 1994.

  19. The injector of the storage ring ANKA; Der Injektor der Speicherringanlage ANKA

    Energy Technology Data Exchange (ETDEWEB)

    Einfeld, D.; Pont, M. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). FGS

    2000-07-01

    The injector of the ANKA storage ring should create a beam of electrons and accelerate them to 500 MeV ready to be injected into the storage ring. This is accomplished with a combination of a microtron and a booster synchrotron, which we call the injector system of ANKA. The microtron delivers a pulse of 1 {mu}sec length with a current of 10 mA. The energy of the electrons when leaving the microtron is 53 MeV. The injection transfer line transports this beam to the booster synchrotron where the electron beam is accelerated to 500 MeV. At 500 MeV another transfer line, the so called extraction transfer line transports the beam to the storage ring. The repetition rate is 1 Hz. (orig.)

  20. Photoswitchable Molecular Rings for Solar-Thermal Energy Storage.

    Science.gov (United States)

    Durgun, E; Grossman, Jeffrey C

    2013-03-21

    Solar-thermal fuels reversibly store solar energy in the chemical bonds of molecules by photoconversion, and can release this stored energy in the form of heat upon activation. Many conventional photoswichable molecules could be considered as solar thermal fuels, although they suffer from low energy density or short lifetime in the photoinduced high-energy metastable state, rendering their practical use unfeasible. We present a new approach to the design of chemistries for solar thermal fuel applications, wherein well-known photoswitchable molecules are connected by different linker agents to form molecular rings. This approach allows for a significant increase in both the amount of stored energy per molecule and the stability of the fuels. Our results suggest a range of possibilities for tuning the energy density and thermal stability as a function of the type of the photoswitchable molecule, the ring size, or the type of linkers.

  1. Steady State Microbunching for High Brilliance and High Repetition Rate Storage Ring-Based Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Alex; Ratner, Daniel; /SLAC; Jiao, Yi; /Beijing, Inst. High Energy Phys.

    2012-09-06

    Electron-based light sources have proven to be effective sources of high brilliance, high frequency radiation. Such sources are typically either linac-Free Electron Laser (FEL) or storage ring types. The linac-FEL type has high brilliance (because the beam is microbunched) but low repetition rate. The storage ring type has high repetition rate (rapid beam circulation) but comparatively low brilliance or coherence. We propose to explore the feasibility of a microbunched beam in a storage ring that promises high repetition rate and high brilliance. The steady-state-micro-bunch (SSMB) beam in storage ring could provide CW sources for THz, EUV, or soft X-rays. Several SSMB mechanisms have been suggested recently, and in this report, we review a number of these SSMB concepts as promising directions for high brilliance, high repetition rate light sources of the future. The trick of SSMB lies in the RF system, together with the associated synchrotron beam dynamics, of the storage ring. Considering various different RF arrangements, there could be considered a number of scenarios of the SSMB. In this report, we arrange these scenarios more or less in order of the envisioned degree of technical challenge to the RF system, and not in the chronological order of their original references. Once the stored beam is steady-state microbunched in a storage ring, it passes through a radiator repeatedly every turn (or few turns). The radiator extracts a small fraction of the beam energy as coherent radiation with a wavelength corresponding to the microbunched period of the beam. In contrast to an FEL, this radiator is not needed to generate the microbunching (as required e.g. by SASE FELs or seeded FELs), so the radiator can be comparatively simple and short.

  2. Commissioning of the DESIREE storage rings - a new facility for cold ion-ion collisions

    Science.gov (United States)

    Gatchell, M.; Schmidt, H. T.; Thomas, R. D.; Rosén, S.; Reinhed, P.; Löfgren, P.; Brännholm, L.; Blom, M.; Björkhage, M.; Bäckström, E.; Alexander, J. D.; Leontein, S.; Hanstorp, D.; Zettergren, H.; Liljeby, L.; Källberg, A.; Simonsson, A.; Hellberg, F.; Mannervik, S.; Larsson, M.; Geppert, W. D.; Rensfelt, K. G.; Danared, H.; Paál, A.; Masuda, M.; Halldén, P.; Andler, G.; Stockett, M. H.; Chen, T.; Källersjö, G.; Weimer, J.; Hansen, K.; Hartman, H.; Cederquist, H.

    2014-04-01

    We report on the ongoing commissioning of the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. Beams of atomic carbon anions (C-) and smaller carbon anion molecules (C-2, C-3, C-4 etc.) have been produced in a sputter ion source, accelerated to 10 keV or 20 keV, and stored successfully in the two electrostatic rings. The rings are enclosed in a common vacuum chamber cooled to below 13 Kelvin. The DESIREE facility allows for studies of internally relaxed single isolated atomic, molecular and cluster ions and for collision experiments between cat- and anions down to very low center-of-mass collision energies (meV scale). The total thermal load of the vacuum chamber at this temperature is measured to be 32 W. The decay rates of stored ion beams have two components: a non-exponential component caused by the space charge of the beam itself which dominates at early times and an exponential term from the neutralization of the beam in collisions with residual gas at later times. The residual gas limited storage lifetime of carbon anions in the symmetric ring is over seven minutes while the 1/e lifetime in the asymmetric ring is measured to be about 30 seconds. Although we aim to improve the storage in the second ring, the number of stored ions are now sufficient for many merged beams experiments with positive and negative ions requiring milliseconds to seconds ion storage.

  3. Preliminary application of turn-by-turn data analysis to the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-Hui; ZHAO Zhen-Tang

    2009-01-01

    There is growing interest in utilizing the beam position monitor turn-by-turn (TBT) data to debug accelerators. TBT data can be used to determine the linear optics, coupled optics and nonlinear behaviors of the storage ring lattice. This is not only a useful complement to other methods of determining the linear optics such as LOCO, but also provides a possibility to uncover more hidden phenomena. In this paper, a preliminary application of a β function measurement to the SSRF storage ring is presented.

  4. A Genetic Algorithm for Chromaticity Correction in Diffraction Limited Storage Rings

    CERN Document Server

    Ehrlichman, Michael

    2016-01-01

    An multi-objective genetic algorithm is developed for optimizing nonlinearities in diffraction limited storage rings. This algorithm determines sextupole and octupole strengths for chromaticity correction that deliver optimized dynamic aperture and beam lifetime. The algorithm makes use of dominance constraints to breed desirable properties into the early generations. The momentum aperture is optimized indirectly by constraining the chromatic tune footprint and optimizing the off-energy dynamic aperture. The result is an effective and computationally efficient technique for correcting chromaticity in a storage ring while maintaining optimal dynamic aperture and beam lifetime. This framework was developed for the Swiss Light Source (SLS) upgrade project.

  5. Design and fabrication of the first quadrupole magnet for the ILSF storage ring

    Directory of Open Access Journals (Sweden)

    F Saeidi

    2015-09-01

    Full Text Available The Iranian Light Source Facility (ILSF is a new 3 GeV third generation synchrotron light source which is consisted of several pre-accelerators and a storage ring with the beam current of 400 mA. Based on the main lattice candidate, the storage ring includes of 100 dipoles, 320 quadrupoles and 320 sextupole magnets. To develop fabrication procedures and techniques and to compare the measurement results with the design data, a series of lattice magnets have been fabricated inside Iran with internal industries. In this article the first prototype quadrupole magnet fabrication process has been described

  6. US-Japan collaboration in the construction of the BNL superconducting muon storage ring and inflector

    Energy Technology Data Exchange (ETDEWEB)

    Hirabayashi, Hiromi; Yamamoto, Akira [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

    2003-03-01

    The US-Japan collaboration in the contraction of a BNL muon storage ring for the g-2 experiment (E821) is described from the viewpoint of Japanese collaborators. Japan has contributed in the production of the pole pieces made of a vacuum-melted Ultra-Low Carbon Steel, Al-stabilized Nb/Ti superconductors for the superferric storage ring dipole coils, including technology transfer, and the development of a sophisticated superconducting inflector for muon injection. All of above items seem to be essential techniques to pursue accurate and detailed muon g-2 experiments. Recent experimental results are also mentioned in the latter part of this report. (author)

  7. New chromaticity compensation approach and dynamic aperture increase in the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    TIAN Shun-Qiang; HOU Jie; CHEN Guang-Ling; LIU Gui-Min

    2008-01-01

    Strong chromatic sextupoles used to compensate natural chromaticities in the third generation light source storage ring usually reduce dynamic aperture drastically.Many optimization methods can be used to find solutions that provide large dynamic apertures.This paper discusses a new optimization approach of sextupole strengths with step-by-step procedure,which is applied in the SSRF storage ring,and a better solution is obtained.Investigating driving terms generated by the sextupoles in every step can analyze their convergences and guide the weight setting among different terms in object function of the single resonance approach based on the perturbation theory.

  8. Optics for the lattice of the compact storage ring for a Compton X-ray source

    Institute of Scientific and Technical Information of China (English)

    YU Pei-Cheng; WANG Yu; SHEN Xiao-zhe; HUANG Wen-Hui; YAN Li-xin; DU Ying-Chao; LI Ren-Kai; TANG Chuan-Xiang

    2009-01-01

    We present two types of optics for the lattice of a compact storage ring for a Compton X-ray source.The optics design for different operation modes of the storage ring are discussed in detail.For the pulse mode optics,an IBS-suppression scheme is applied to optimize the optics for lower IBS emittance growth rate;as for the steady mode,the method to control momentum compact factor is adopted[Gladkikh P,Phys.Rev.ST Accel.Beams 8,050702]to obtain stability of the electron beam.

  9. The heavy ion cooler-storage-ring project (HIRFL-CSR) at Lanzhou

    CERN Document Server

    Xia, J W; Wei, B W; Yuan, Y J; Song, M T; Zhang, W Z; Yang, X D; Yuan Ping; Gao, D Q; Zhao, H W; Yang, X T; Xiao, G Q; Man, K T; Dang, J R; Cai, X H; Wang, Y F; Tang, J Y; Qiao, W M; Rao, Y N; He, Y; Mao, L Z; Zhou, Z Z

    2002-01-01

    HIRFL-CSR, a new ion Cooler-Storage-Ring (CSR) project, is the post-acceleration system of the Heavy Ion Research Facility in Lanzhou (HIRFL). It consists of a main ring (CSRm) and an experimental ring (CSRe). From the HIRFL cyclotron system the heavy ions will be accumulated, cooled and accelerated in the CSRm, then extracted fast to produce radioactive ion beams (RIB) or highly charged heavy ions. Those secondary beams will be accepted and stored by the CSRe for many internal-target experiments with electron cooling.

  10. Design of the SSRF storage ring magnet lattice

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Shanghai Synchrotron Radiation Facility (SSRF) is a proposed 3rd generation light source with 3.5 GeV in energy. It is composed of 20 DBA cells resulting in a ring that is about 10 nm(rad in emittance and 396 m in circumference, and provides 10 straight sections of 7.24 m and other 10 straight sections of 5.0 m for the inclusion of insertion devices, injection components and RF cavities. The lattice has high flexibility, and the tunes and beta functions can be easily adjusted within a wide range to meet the requirements for different operation modes, including high beta mode and hybrid beta mode with and/or without dispersion in straight sections. In this paper, the results of linear optics design and dynamic aperture study are presented.

  11. Environmental research at Berkeley

    CERN Multimedia

    1973-01-01

    The information concerning the Energy and Environment Programme at the Lawrence Berkeley Laboratory is based on a talk given at CERN by A.M. Sessler, one of the initiators of the Programme. (Dr. Sessler has been appointed Director of the Lawrence Berkeley Laboratory, in succession to Prof. E. M. McMillan, from 1 November.) Many of the topics mentioned merit an extended story in themselves but the purpose of this article is simply to give a sketch of what is happening.

  12. Limitation on the luminosity of e+e- storage rings due to beamstrahlung

    CERN Document Server

    Telnov, V I

    2013-01-01

    Particle loss due to the emission of single energetic beamstrahlung photons in beam collisions is shown to impose a fundamental limit on storage-ring luminosities at energies greater than 2E~140 GeV for head-on collisions and 2E~40 GeV for crab-waist collisions. Above these threshold energies, the suppression factor due to beamstrahlung scales as 1/E^{4/3}, and for a fixed power of synchrotron radiation, the luminosity L is proportional to R/E^{13/3}, where R is the collider radius. For 2E > 150 GeV, both collision schemes have similar luminosity limits. The luminosities attainable at storage-ring and linear-collider (LC) 2E=240 GeV Higgs factories are comparable; at higher energies, LCs are preferable. This conference paper is based on my recent PRL publication [1], supplemented with additional comments on linac-ring e+e- colliders and ring e+e- colliders with charge compensation (four-beam collisions).

  13. Modern Ives-Stilwell Experiments At Storage Rings: Large Boosts Meet High Precision

    CERN Document Server

    Gwinner, G; Geppert, C; Huber, G; Karpuk, S; Krieger, A; Nörtershäuser, W; Novotny, C; Kühl, T; Sanchez, R; Stöhlker, T; Bing, D; Schwalm, D; Wolf, A; Hänsch, T W; Reinhardt, S; Saathoff, G

    2013-01-01

    We give a brief overview of time dilation tests using high-resolution laser spectroscopy at heavy-ion storage rings. We reflect on the various methods used to eliminate the first-order Doppler effect and on the pitfalls encountered, and comment on possible extensions at future facilities providing relativistic heavy ion beams at $\\gamma \\gg 1$.

  14. Spin flip by RF-field at storage rings with siberian snakes

    Energy Technology Data Exchange (ETDEWEB)

    Koop, I.; Shatunov, Y. [Budker Institute for Nuclear Physics, Novosibirsk, 630090 (Russia)

    1995-09-01

    The beam dynamics and optics of spin flipping polarized beams with an RF field in storage rings with Siberian Snakes is discussed. The dispersion relations are determined and depolarization of the beams are discussed. (AIP) {copyright} {ital 1995 American Institute of Physics.}

  15. Laser-rf double-resonance spectroscopy in a storage ring

    Science.gov (United States)

    Kristensen, M.; Hangst, J. S.; Jessen, P. S.; Nielsen, J. S.; Poulsen, O.; Shi, P.

    1992-10-01

    Laser-rf double-resonance spectroscopy of the hyperfine transition between F''=0 and F'=1 in the metastable 3S1 state of 6Li+ was performed in 100-keV beam in the storage ring ASTRID. High efficiency of optical pumping was demonstrated for complex pumping schemes. A broadband (dc-6 GHz) rf device was designed and used for rf spectroscopy in the storage ring. The possibility of obtaining coherent rf signals (Ramsey fringes) from successive interactions with the same field was investigated. Important limitations for the coherences due to magnetic-field inhomogeneities were observed. These led to randomization of the atomic polarization during only one turn in the storage ring and completely prevented observation of Ramsey fringes. This situation is different from the case of fundamental particles in a storage ring, where the polarization may be preserved for many round-trips. Limits were put on the demands to beam quality, beam positioning, and magnetic-field quality to overcome the problem. The effects of the rf device on the external degrees of freedom of the ion beam were investigated. Its small aperture substantially reduced the beam lifetime, and at very low rf frequencies the electric field in the rf device was able to excite external transverse resonances in the beam.

  16. Effects of CSR Generated from Upstream Bends in a Laser Plasma Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, C.; Qiang, J.; Venturini, M.

    2013-08-28

    The recent proposal [1] of a Laser Plasma Storage Ring (LPSR) envisions the use of a laser-plasma (LP) acceleration module to inject an electron beam into a compact 500 MeV storage ring. Electron bunches generated by LP methods are naturally very short (tens of femtoseconds), presenting peak currents on the order of 10 kA or higher. Of obvious concern is the impact of collective effects and in particular Coherent Synchrotron Radiation (CSR) on the beam dynamics in the storage ring. Available simulation codes (e.g. Elegant [2]) usually include transient CSR effects but neglect the contribution of radiation emitted from trailing magnets. In a compact storage ring, with dipole magnets close to each other, cross talking between different magnets could in principle be important.In this note we investigate this effect for the proposed LPSR and show that, in fact, this effect is relatively small. However our analysis also indicates that CSR effects in general would be quite strong and deserve a a careful study.

  17. Compact storage ring to search for the muon electric dipole moment

    NARCIS (Netherlands)

    Adelmann, A.; Kirch, K.; Onderwater, C. J. G.; Schietinger, T.

    2010-01-01

    We present the concept of a compact storage ring of less than 0.5 m orbit radius to search for the electric dipole moment (EDM) of the muon (d(mu)) by adapting the 'frozen spin' method. At existing muon facilities a statistics limited sensitivity of d(mu) similar to 7 x 10(-23) e cm can be achieved

  18. Towards the ultimate storage ring: the lattice design for Beijing Advanced Photon Source

    CERN Document Server

    Gang, Xu

    2013-01-01

    A storage ring-based light source, Beijing Advanced Photon Source (BAPS) is proposed to store 5-GeV low-emittance electron beam and to provide high-brilliance coherent radiation. In this paper, we report our efforts of pushing down the emittance of BAPS to approach the so-called ultimate storage ring, while fixing the circumference to about 1200 m. To help dealing with the challenge of beam dynamics associated with the intrinsic very strong nonlinearities in an ultralow-emittance ring, a combination of several progressive technologies is used in the linear optics design and nonlinear optimization, such as modified theoretical minimum emittance cell with small-aperture magnets, quasi-3rd-order achromat, theoretical analyzer based on Lie Algebra and Hamiltonian analysis, multi-objective genetic algorithm, and frequency map analysis. These technologies enable us to obtain satisfactory beam dynamics in one lattice design with natural emittance of 75 pm.

  19. Nonlinear and long-term beam dynamics in low energy storage rings

    Science.gov (United States)

    Papash, A. I.; Smirnov, A. V.; Welsch, C. P.

    2013-06-01

    Electrostatic storage rings operate at very low energies in the keV range and have proven to be invaluable tools for atomic and molecular physics. Because of the mass independence of electric rigidity, these machines are able to store a wide range of different particles, from light ions to heavy singly charged biomolecules, opening up unique research opportunities. However, earlier measurements have shown strong limitations in maximum beam intensity, fast decay of the stored ion current, and reduced beam lifetime. The nature of these effects has not been fully understood and an improved understanding of the physical processes influencing beam motion and stability in such rings is needed. In this paper, a comprehensive study into nonlinear and long-term beam dynamics studies is presented on the examples of a number of existing and planned electrostatic storage rings using the BETACOOL, OPERA-3D, and MAD-X simulation software. A detailed investigation into ion kinetics, under consideration of effects from electron cooling and multiple scattering of the beam on a supersonic gas jet target, is carried out and yields a consistent explanation of the physical effects in a whole class of storage rings. The lifetime, equilibrium momentum spread, and equilibrium lateral spread during collisions with the target are estimated. In addition, the results from experiments at the Test Storage Ring, where a low-intensity beam of CF+ ions at 93keV/u has been shrunk to extremely small dimensions, are reproduced. Based on these simulations, the conditions for stable ring operation with an extremely low-emittance beam are presented. Finally, results from studies into the interaction of 3-30 keV ions with a gas jet target are summarized.

  20. Symplectic orbit and spin tracking code for all-electric storage rings

    Science.gov (United States)

    Talman, Richard M.; Talman, John D.

    2015-07-01

    Proposed methods for measuring the electric dipole moment (EDM) of the proton use an intense, polarized proton beam stored in an all-electric storage ring "trap." At the "magic" kinetic energy of 232.792 MeV, proton spins are "frozen," for example always parallel to the instantaneous particle momentum. Energy deviation from the magic value causes in-plane precession of the spin relative to the momentum. Any nonzero EDM value will cause out-of-plane precession—measuring this precession is the basis for the EDM determination. A proposed implementation of this measurement shows that a proton EDM value of 10-29e -cm or greater will produce a statistically significant, measurable precession after multiply repeated runs, assuming small beam depolarization during 1000 s runs, with high enough precision to test models of the early universe developed to account for the present day particle/antiparticle population imbalance. This paper describes an accelerator simulation code, eteapot, a new component of the Unified Accelerator Libraries (ual), to be used for long term tracking of particle orbits and spins in electric bend accelerators, in order to simulate EDM storage ring experiments. Though qualitatively much like magnetic rings, the nonconstant particle velocity in electric rings gives them significantly different properties, especially in weak focusing rings. Like the earlier code teapot (for magnetic ring simulation) this code performs exact tracking in an idealized (approximate) lattice rather than the more conventional approach, which is approximate tracking in a more nearly exact lattice. The Bargmann-Michel-Telegdi (BMT) equation describing the evolution of spin vectors through idealized bend elements is also solved exactly—original to this paper. Furthermore the idealization permits the code to be exactly symplectic (with no artificial "symplectification"). Any residual spurious damping or antidamping is sufficiently small to permit reliable tracking for the

  1. Experimental modelling of the dipole magnet for the electron storage ring DELSY

    CERN Document Server

    Meshkov, I N; Syresin, E M

    2003-01-01

    In the Joint Institute for Nuclear Research (Dubna) the project of Dubna Electron Synchrotron (DELSY) with an electron energy of 1.2 GeV is developed. The electron storage ring in the DELSY project is planned to be created on the basis of magnetic elements, which were used earlier in the storage ring AmPS (NIKHEF, Amsterdam). The optics of the ring is necessary to be changed, its perimeter to be reduced approximately in one and a half time, the energy of electrons to be increased. The paper is devoted to the development of a modified dipole magnet of the storage ring. The preliminary estimation of geometry of the magnet pole is carried out by means of computer modelling using two- and three- dimensional codes of the magnetic field calculation SUPERFISH and RADIA. The experimental stand for the measurements of the dipole magnetic field is described. As the result of calculational and experimental modelling for the dipole magnet, the geometry of its poles was estimated, providing in the horizontal aperture +- 3...

  2. Effectiveness of rf phase modulation for increasing bunch length in electron storage rings

    Science.gov (United States)

    Orsini; Mosnier

    2000-04-01

    Aiming at increasing the apparent bunch length and hence the beam lifetime in electron storage rings, rf phase modulation near one parametric resonance has been experimentally investigated. Since the possible benefit of this technique depends greatly on the ring parameters, we studied the effect of such a modulation for different rf parameters on the longitudinal emittance. Theoretical predictions and results of simulations are compared and discussed. It is shown that synchrotron radiation tends to spoil the parametric resonance. In particular, a criterion for island survival has been found.

  3. Calibration of the Nonlinear Accelerator Model at the Diamond Storage Ring

    CERN Document Server

    Bartolini, Riccardo; Rowland, James; Martin, Ian; Schmidt, Frank

    2010-01-01

    The correct implementation of the nonlinear ring model is crucial to achieve the top performance of a synchrotron light source. Several dynamics quantities can be used to compare the real machine with the model and eventually to correct the accelerator. Most of these methods are based on the analysis of turn-by-turn data of excited betatron oscillations. We present the experimental results of the campaign of measurements carried out at the Diamond. A combination of Frequency Map Analysis (FMA) and detuning with momentum measurements has allowed a precise calibration of the nonlinear model capable of reproducing the nonlinear beam dynamics in the storage ring

  4. El idealismo de Berkeley

    Directory of Open Access Journals (Sweden)

    David Sobrevilla

    1995-12-01

    Full Text Available En esta conferencia se examina en qué consiste el idealismo de Berkeley. Para ello se sigue el mismo camino propuesto por G .J. Warnock: se indaga contra qué se opone Berkeley, el materialismo, y cómo lo entiende, y por qué está en contra del mismo. A continuación se reexamina el idealismo berkeleyano, y en la consideración final se juzgan sus virtudes y defectos: algunas de las críticas fundadas que se le han formulado y la visión de la ciencia que se desprende de los escritos de Berkeley. A este respecto se pone en conexión las ideas del autor con algunos planteamientos del último Husserl y con una interpretación de Popper sobre la sorprendente modernidad de algunas de las ideas berkeleyanas sobre la ciencia.

  5. First storage of ion beams in the Double Electrostatic Ion-Ring Experiment: DESIREE

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, H. T.; Thomas, R. D.; Gatchell, M.; Rosen, S.; Reinhed, P.; Loefgren, P.; Braennholm, L.; Blom, M.; Bjoerkhage, M.; Baeckstroem, E.; Alexander, J. D.; Leontein, S.; Zettergren, H.; Liljeby, L.; Kaellberg, A.; Simonsson, A.; Hellberg, F.; Mannervik, S.; Larsson, M.; Geppert, W. D. [Department of Physics, Stockholm University, SE-10691 Stockholm (Sweden); and others

    2013-05-15

    We report on the first storage of ion beams in the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. We have produced beams of atomic carbon anions and small carbon anion molecules (C{sub n}{sup -}, n= 1, 2, 3, 4) in a sputter ion source. The ion beams were accelerated to 10 keV kinetic energy and stored in an electrostatic ion storage ring enclosed in a vacuum chamber at 13 K. For 10 keV C{sub 2}{sup -} molecular anions we measure the residual-gas limited beam storage lifetime to be 448 s {+-} 18 s with two independent detector systems. Using the measured storage lifetimes we estimate that the residual gas pressure is in the 10{sup -14} mbar range. When high current ion beams are injected, the number of stored particles does not follow a single exponential decay law as would be expected for stored particles lost solely due to electron detachment in collision with the residual-gas. Instead, we observe a faster initial decay rate, which we ascribe to the effect of the space charge of the ion beam on the storage capacity.

  6. Beam dynamics simulations in laser electron storage rings and optical stochastic cooling

    Science.gov (United States)

    Duru, Alper

    Laser-electron storage rings are potential compact X-ray sources. Longitudinal dynamics in laser-electron storage rings is studied including the effects of both laser interaction and synchrotron radiation. It is shown that the steady state energy spread can reach as high as a few percent. The main reason is the wide spread in the energy loss by electrons to laser photons. Optical stochastic cooling has been studied numerically. The effects of the finite bandwidth of the amplifier are mixing and signal distortion. Both are included in the simulations and the results are compared to theoretical results. It is shown that the beam can be cooled both in transverse and longitudinal phase phase spaces simultaneously.

  7. Beam Performance and Luminosity Limitations in the High-Energy Storage Ring (HESR)

    CERN Document Server

    Lehrach, A; Hinterberger, F; Maier, R; Prasuhn, D

    2006-01-01

    The High-Energy Storage Ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt is planned as an antiproton synchrotron and storage ring in the momentum range from 1.5 to 15 GeV/c. An important feature of this new facility is the combination of phase space cooled beams with dense internal targets (e.g. pellet targets), resulting in demanding beam parameter of two operation modes: high luminosity mode with peak luminosities up to 2*10^32 cm-2 s-1, and high resolution mode with a momentum spread down to 10^-5, respectively. To reach these beam parameters very powerful phase space cooling is needed, utilizing high-energy electron cooling and high-bandwidth stochastic cooling. The effect of beam-target scattering and intra-beam interaction is investigated in order to study beam equilibria and beam losses for the two different operation modes.

  8. Beam performance and luminosity limitations in the high-energy storage ring (HESR)

    Science.gov (United States)

    Lehrach, A.; Boine-Frankenheim, O.; Hinterberger, F.; Maier, R.; Prasuhn, D.

    2006-06-01

    The high-energy storage ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt is planned as an antiproton synchrotron storage ring in the momentum range 1.5-15 GeV/ c. An important feature of this new facility is the combination of phase space cooled beams and dense internal targets (e.g. pellet targets), which results in demanding beam parameter requirements for two operation modes: high luminosity mode with peak luminosities to 2×10 32 cm -2 s -1, and high-resolution mode with a momentum spread down to 10 -5. To reach these beam parameters one needs a very powerful phase space cooling, utilizing high-energy electron cooling and high-bandwidth stochastic cooling. The effects of beam-target scattering and intra-beam interaction are investigated in order to study beam equilibria and beam losses for the two different operation modes.

  9. Ion Optics of the HESR storage ring at FAIR for operation with heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Kovalenko, Oleksandr; Dolinskyy, Oleksiy; Litvinov, Yuri; Stoehlker, Thomas [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

    2014-07-01

    High Energy Storage Ring (HESR) of the FAIR project is primarily designed for internal target experiments with stored and cooled antiprotons, which is the main objective of the PANDA collaboration. However, the HESR storage ring also appears to have remarkable properties to carry out physics experiments with heavy ions. This paper proposes a new ion optical design allowing for the heavy ion operation mode of the HESR. The main goal was to provide an optics which meets the requirements of the future experiments with heavy ion beams. In connection, issues like closed orbit correction, dynamic aperture as well as other characteristics of beam dynamics of the new ion optical setup are under analysis in this study.

  10. A modeling GUI for accelerator physics of the storage ring at SSRF

    Institute of Scientific and Technical Information of China (English)

    CHEN Guangling; TIAN Shunqiang; LIU Guimin; JIANG Bocheng

    2009-01-01

    In this paper, we report a MATLAB-based GUI tool, bodgui, which integrates functions of lattice editor,linear match, and nonlinear optimization, and visualized tracking functions for beam optics design. A user can switch his/ber design procedures one to another. Flexibilities are provided for adjusting or optimizing the lattice settings in commissioning or operation of the accelerators. The algorithm of the linear match and nonlinear optimization, and the GUI windows including the main functions and running status, are presented. The SSRF storage ring was employed as a test lattice. Several optics modes designed and optimized by the GUI tools were used for commissioning the storage ring. Functions of bodgui tool are machine-independent, and it can be well applied to modern light sources being built in other parts of the world.

  11. Measurement of the Beam Longitudinal Profile in a Storage Ring by Non-Linear Laser Mixing

    Science.gov (United States)

    Beche, J.-F.; Byrd, J.; De Santis, S.; Denes, P.; Placidi, M.; Turner, W.; Zolotorev, M.

    2004-11-01

    We report on the development of a new technique for the measurement of the longitudinal beam profile in storage rings. This technique, which has been successfully demonstrated at the Advanced Light Source, mixes the synchrotron radiation with the light from a mode-locked solid-state laser oscillator in a non-linear crystal. The up-converted radiation is then detected with a photomultiplier and processed to extract, store, and display the required information. The available choices of laser repetition frequency, pulse width, and phase modulation give a wide range of options for matching the bunch configuration of a particular storage ring. Besides the dynamic measurement of the longitudinal profile of each bunch, the instrument can monitor the evolution of the bunch tails, the presence of un trapped particles, and their diffusion into nominally empty RF buckets ("ghost bunches").

  12. Measurement of the beam longitudinal profile in a storage ring bynon-linear laser mixing

    Energy Technology Data Exchange (ETDEWEB)

    Beche, J.-F.; Byrd, J.; De Santis, S.; Denes, P.; Placidi, M.; Turner, W.; Zolotorev, M.

    2004-05-03

    We report on the development of a new technique for the measurement of the longitudinal beam profile in storage rings. This technique, which has been successfully demonstrated at the Advanced Light Source, mixes the synchrotron radiation with the light from a mode-locked solid state laser oscillator in a non-linear crystal. The up-converted radiation is then detected with a photomultiplier and processed to extract, store, and display the required information. The available choices of laser repetition frequency, pulse width, and phase modulation give a wide range of options for matching the bunch configuration of a particular storage ring. Besides the dynamic measurement of the longitudinal profile of each bunch, the instrument can monitor the evolution of the bunch tails, the presence of untrapped particles and their diffusion into nominally empty RF buckets (''ghostbunches'').

  13. Steady-State Microbunching in a Storage Ring for Generating Coherent Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ratner, Daniel F.; /Stanford U., Appl. Phys. Dept.; Chao, Alexander W.; /SLAC

    2011-05-19

    Synchrotrons and storage rings deliver radiation across the electromagnetic spectrum at high repetition rates, and free electron lasers (FELs) produce radiation pulses with high peak brightness. However, at present few light sources can generate both high repetition rate and high brightness outside the optical range. We propose to create steady-state microbunching (SSMB) in a storage ring to produce coherent radiation at a high repetition rate or in continuous wave (CW) mode. In this paper we describe a general mechanism for producing SSMB and give sample parameters for EUV lithography and sub-millimeter sources. We also describe a similar arrangement to produce two pulses with variable spacing for pump-probe experiments. With technological advances, SSMB could reach the soft X-ray range (< 10 nm).

  14. Study of Magnetic Hysteresis Effects in a Storage Ring Using Precision Tune Measurement

    CERN Document Server

    Li, Wei; Mikhailov, Stepan F; Xu, Wei; Li, Jing-Yi; Li, Wei-Min; Wu, Ying K

    2016-01-01

    With advances in accelerator science and technology in the recent decades, the accelerator community has focused on the development of next-generation light sources, for example the diffraction-limited storage rings (DLSRs), which requires precision control of the electron beam energy and betatron tunes. This work is aimed at understanding magnet hysteresis effects on the electron beam energy and lattice focusing in the circular accelerators, and developing new methods to gain better control of these effects. In this paper, we will report our recent experimental study of the magnetic hysteresis effects and their impacts on the Duke storage ring lattice using the transverse feedback based precision tune measurement system. The major magnet hysteresis effects associated with magnet normalization and lattice ramping are carefully studied to determine an effective procedure for lattice preparation while maintaining a high degree of reproducibility of lattice focusing. The local hysteresis effects are also studied...

  15. Applications of differential algebra to single-particle dynamics in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Y.

    1991-09-01

    Recent developments in the use of differential algebra to study single-particle beam dynamics in charged-particle storage rings are the subject of this paper. Chapter 2 gives a brief review of storage rings. The concepts of betatron motion and synchrotron motion, and their associated resonances, are introduced. Also introduced are the concepts of imperfections, such as off-momentum, misalignment, and random and systematic errors, and their associated corrections. The chapter concludes with a discussion of numerical simulation principles and the concept of one-turn periodic maps. In Chapter 3, the discussion becomes more focused with the introduction of differential algebras. The most critical test for differential algebraic mapping techniques -- their application to long-term stability studies -- is discussed in Chapter 4. Chapter 5 presents a discussion of differential algebraic treatment of dispersed betatron motion. The paper concludes in Chapter 6 with a discussion of parameterization of high-order maps.

  16. Recombination and Ionization Measurements at the Heidelberg Heavy Ion Storage Ring TSR

    Science.gov (United States)

    Hahn, M.; Lestinsky, M.; Novotný, O.; Savin, D. W.; Bernhardt, D.; Müller, A.; Schippers, S.; Krantz, C.; Grieser, M.; Repnow, R.; Wolf, A.

    2011-05-01

    Knowledge of the charge state distribution (CSD) of astrophysical plasmas is important for the interpretation of spectroscopic data. To accurately calculate CSDs, reliable rate coefficients are needed for dielectronic recombination (DR), which is the dominant electron-ion recombination mechanism for most ions, and for electron impact ionization (EII). We are carrying out DR and EII measurements of astrophysically important ions using the TSR storage ring at the Max-Plank-Institute for Nuclear Physics in Heidelberg, Germany. Storage ring measurements are largely free of the metastable contamination found in other experimental geometries, resulting in more unambiguous DR and EII reaction rate measurements. The measured data can be used in plasma modelling as well as for benchmarking theoretical atomic calculations.

  17. Improved nonlinear optimization in the storage ring of the modern synchrotron radiation light source

    Institute of Scientific and Technical Information of China (English)

    TIAN Shun-Qiang; LIU Gui-Min; HOU Jie; CHEN Guang-Ling; CHEN Sen-Yu

    2009-01-01

    In the storage ring of the third generation light sources,nonlinear optimization is an indispensable course in order to obtain ample dynamic acceptances and to reach high injection efficiency and long beam lifetime,especially in a low emittance lattice.An improved optimization algorithm based on the single resonance approach,which takes relative weight and initial Harmonic Sextupole Integral Strength (HSIS) as search variables,is discussed in this paper.Applications of the improved method in several test lattices are presented.Detailed analysis of the storage ring of the Shanghai Synchrotron Radiation Facility (SSRF) is particularly emphasized.Furthermore,cancellation of the driving terms is investigated to reveal the physical mechanism of the harmonic sextupole compensation.Sensitivity to the weight and the initial HSIS as well as dependence of the optimum solution on the convergent factor is analyzed.

  18. Intense inverse compton {gamma}-ray source from Duke storage ring FEL

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko, V.N.; Madey, J.M.J. [Duke Univ., Durham, NC (United States)

    1995-12-31

    We suggest using FEL intracavity power in the Duke storage ring fortrays production via Inverse Compton Backscattering (ICB). The OK-4 FEL driven by the Duke storage ring will tens of watts of average lasing power in the UV/VUV range. Average intracavity power will be in kilowatt range and can be used to pump ICB source. The {gamma}-rays with maximum energy from 40 MeV to 200 MeV with intensity of 0.1-5 10{sup 10}{gamma} per second can be generated. In this paper we present expected parameters of {gamma}-ray beam parameters including its intensity and distribution. We discuss influence of e-beam parameters on collimated {gamma}-rays spectrum and optimization of photon-electron interaction point.

  19. Analytical Benchmarking, Precision Particle Tracking, Electric and Magnetic Storage Rings, Runge-Kutta, Predictor-Corrector

    CERN Document Server

    Metodiev, E M; Fandaros, M; Haciomeroglu, S; Huang, D; Huang, K L; Patil, A; Prodromou, R; Semertzidis, O A; Sharma, D; Stamatakis, A N; Orlov, Y F; Semertzidis, Y K

    2015-01-01

    A set of analytical benchmarks for tracking programs are required for precision storage ring experiments. To determine the accuracy of precision tracking programs in electric and magnetic rings, a variety of analytical estimates of particle and spin dynamics in the rings are developed and compared to the numerical results of tracking simulations. Initial discrepancies in the comparisons indicated the need for improvement of several of the analytical estimates. As an example, we find that the fourth order Runge-Kutta/Predictor-Corrector method was accurate but slow, and that it passed all the benchmarks it was tested against, often to the sub-part per billion level. Thus high precision analytical estimates and tracking programs based on fourth order Runge-Kutta/Predictor-Corrector integration can be used to benchmark faster tracking programs for accuracy.

  20. Dynamical aspects on FEL interaction in single passage and storage ring devices

    Energy Technology Data Exchange (ETDEWEB)

    Dattoli, G.; Renieri, A. [ENEA, Frascati (Italy)

    1995-12-31

    The dynamical behaviour of the free-electron lasers is investigated using appropriate scaling relations valid for devices operating in the low and high gain regimes, including saturation. The analysis is applied to both single passage and storage ring configurations. In the latter case the interplay between the interaction of the electron bean with the laser field and with the accelerator environment is investigated. In particular we discuss the effect of FEL interaction on the microwave instability.

  1. Design summary of the magnet support structures for the proton storage ring injection line upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Bernardin, J.D.; Ledford, J.E.; Smith, B.G.

    1997-05-01

    This report summarizes the technical engineering and design issues associated with the Proton Storage Ring (PSR) Injection Line upgrade of the Los Alamos Neutron Science Center (LANSCE). The main focus is on the engineering design calculations of several magnet support structures. The general procedure based upon a set number of design criteria is outlined, followed by a case-by-case summary of the engineering design analyses, reutilization or fabrication callouts and design safety factors.

  2. A Storage Ring Experiment to Detect a Proton Electric Dipole Moment

    CERN Document Server

    Anastassopoulos, V; Baartman, R; Bai, M; Baessler, S; Benante, J; Berz, M; Blaskiewicz, M; Bowcock, T; Brown, K; Casey, B; Conte, M; Crnkovic, J; Fanourakis, G; Fedotov, A; Fierlinger, P; Fischer, W; Gaisser, M O; Giomataris, Y; Grosse-Perdekamp, M; Guidoboni, G; Haciomeroglu, S; Hoffstaetter, G; Huang, H; Incagli, M; Ivanov, A; Kawall, D; Khazin, B; Kim, Y I; King, B; Koop, I A; Larsen, R; Lazarus, D M; Lebedev, V; Lee, M J; Lee, S; Lee, Y H; Lehrach, A; Lenisa, P; Sandri, P Levi; Luccio, A U; Lyapin, A; MacKay, W; Maier, R; Makino, K; Malitsky, N; Marciano, W J; Meng, W; Meot, F; Metodiev, E M; Miceli, L; Moricciani, D; Morse, W M; Nagaitsev, S; Nayak, S K; Orlov, Y F; Ozben, C S; Park, S T; Pesce, A; Pile, P; Polychronakos, V; Podobedov, B; Pretz, J; Ptitsyn, V; Ramberg, E; Raparia, D; Rathmann, F; Rescia, S; Roser, T; Sayed, H Kamal; Semertzidis, Y K; Senichev, Y; Sidorin, A; Silenko, A; Simos, N; Stahl, A; Stephenson, E J; Stroeher, H; Syphers, M J; Talman, J; Talman, R M; Tishchenko, V; Touramanis, C; Tsoupas, N; Venanzoni, G; Vetter, K; Vlassis, S; Won, E; Zavattini, G; Zelenski, A; Zioutas, K

    2015-01-01

    A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of $10^{-29}e\\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000~TeV.

  3. A storage ring experiment to detect a proton electric dipole moment.

    Science.gov (United States)

    Anastassopoulos, V; Andrianov, S; Baartman, R; Baessler, S; Bai, M; Benante, J; Berz, M; Blaskiewicz, M; Bowcock, T; Brown, K; Casey, B; Conte, M; Crnkovic, J D; D'Imperio, N; Fanourakis, G; Fedotov, A; Fierlinger, P; Fischer, W; Gaisser, M O; Giomataris, Y; Grosse-Perdekamp, M; Guidoboni, G; Hacıömeroğlu, S; Hoffstaetter, G; Huang, H; Incagli, M; Ivanov, A; Kawall, D; Kim, Y I; King, B; Koop, I A; Lazarus, D M; Lebedev, V; Lee, M J; Lee, S; Lee, Y H; Lehrach, A; Lenisa, P; Levi Sandri, P; Luccio, A U; Lyapin, A; MacKay, W; Maier, R; Makino, K; Malitsky, N; Marciano, W J; Meng, W; Meot, F; Metodiev, E M; Miceli, L; Moricciani, D; Morse, W M; Nagaitsev, S; Nayak, S K; Orlov, Y F; Ozben, C S; Park, S T; Pesce, A; Petrakou, E; Pile, P; Podobedov, B; Polychronakos, V; Pretz, J; Ptitsyn, V; Ramberg, E; Raparia, D; Rathmann, F; Rescia, S; Roser, T; Kamal Sayed, H; Semertzidis, Y K; Senichev, Y; Sidorin, A; Silenko, A; Simos, N; Stahl, A; Stephenson, E J; Ströher, H; Syphers, M J; Talman, J; Talman, R M; Tishchenko, V; Touramanis, C; Tsoupas, N; Venanzoni, G; Vetter, K; Vlassis, S; Won, E; Zavattini, G; Zelenski, A; Zioutas, K

    2016-11-01

    A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of 10(-29) e ⋅ cm by using polarized "magic" momentum 0.7 GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the standard model at the scale of 3000 TeV.

  4. Stability of Coulomb crystals in a linear Paul trap with storage-ring-like confinement

    DEFF Research Database (Denmark)

    Kjærgaard, Niels; Mølhave, Kristian; Drewsen, Michael

    2002-01-01

    We report experiments on the stability of ion Coulomb crystals in a linear Paul trap with storage-ring-like confinement. The transverse dynamics of charged particles in a trap of this type is analogous to that of a fast beam traveling through a channel with periodic, magnetic alternating gradient...... confinement. The experimentally observed stability conditions for stationary crystals comply remarkably well with current theory of crystalline plasmas and beams....

  5. Cascade Problems in Some Atomic Lifetime Measurements at a Heavy-Ion Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Trabert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

    2008-10-09

    Lifetimes of 3s{sup 2}3p{sup k} ground configuration levels of Al-, Si-, P-, and S-like ions of Be, Co, and Ni have been measured at a heavy-ion storage ring. Some of the observed decay curves show strong evidence of cascade repopulation from specific 3d levels that feature lifetimes in the same multi-millisecond range as the levels of the ground configuration.

  6. The double electrostatic ion ring experiment: A unique cryogenic electrostatic storage ring for merged ion-beams studies

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R. D.; Schmidt, H. T.; Andler, G.; Bjoerkhage, M.; Blom, M.; Braennholm, L.; Baeckstroem, E.; Danared, H.; Das, S.; Haag, N.; Hallden, P.; Hellberg, F.; Holm, A. I. S.; Johansson, H. A. B.; Kaellberg, A.; Kaellersjoe, G.; Larsson, M.; Leontein, S.; Liljeby, L.; Loefgren, P. [Department of Physics, Stockholm University, SE-106 91 Stockholm (Sweden); and others

    2011-06-15

    We describe the design of a novel type of storage device currently under construction at Stockholm University, Sweden, using purely electrostatic focussing and deflection elements, in which ion beams of opposite charges are confined under extreme high vacuum cryogenic conditions in separate ''rings'' and merged over a common straight section. The construction of this double electrostatic ion ring experiment uniquely allows for studies of interactions between cations and anions at low and well-defined internal temperatures and centre-of-mass collision energies down to about 10 K and 10 meV, respectively. Position sensitive multi-hit detector systems have been extensively tested and proven to work in cryogenic environments and these will be used to measure correlations between reaction products in, for example, electron-transfer processes. The technical advantages of using purely electrostatic ion storage devices over magnetic ones are many, but the most relevant are: electrostatic elements which are more compact and easier to construct; remanent fields, hysteresis, and eddy-currents, which are of concern in magnetic devices, are no longer relevant; and electrical fields required to control the orbit of the ions are not only much easier to create and control than the corresponding magnetic fields, they also set no upper mass limit on the ions that can be stored. These technical differences are a boon to new areas of fundamental experimental research, not only in atomic and molecular physics but also in the boundaries of these fields with chemistry and biology. For examples, studies of interactions with internally cold molecular ions will be particular useful for applications in astrophysics, while studies of solvated ionic clusters will be of relevance to aeronomy and biology.

  7. Spin decoherence in electron storage rings --- more from a simple model

    CERN Document Server

    Barber, D P

    2015-01-01

    This is an addendum to the paper "Some models of spin coherence and decoherence in storage rings" by one of the authors [1] in which spin diffusion in simple electron storage rings is studied. In particular, we illustrate in a compact way, a key implication in the Epilogue of [1], namely that the exact formalism of [1] delivers a rate of depolarisation which can differ from that obtained by the conventional treatments of spin diffusion which rely on the use of the derivative $\\partial \\hat n/\\partial\\eta$ [2,3,4]. As a vehicle we consider a ring with a Siberian Snake and electron polarisation in the plane of the ring (Machine II in [1]). For this simple setup with its one-dimensional spin motion, we avoid having to deal directly with the Bloch equation [5,6] for the polarisation density. Our treatment, which is deliberately pedagogical, shows that the use of $\\partial \\hat n/\\partial\\eta$ provides a very good approximation to the rate of spin depolarisation in the model considered. But it then shows that the ...

  8. Single bunch injection system for storage ring FEL using an rf photoinjector

    Science.gov (United States)

    O'Shea, P. G.; Lancaster, J. A.; Madey, J. M. J.; Sachtschale, R.; Jones, R.

    1997-05-01

    RF photoinjectors have gained acceptance as the source of choice for high-brightness electron accelerators, but have been quite expensive to build and difficult to operate. In this paper we describe the successful operation of an inexpensive, simple and reliable rf photoinjector suitable for single bunch injection into storage rings. For optimum storage ring FEL and Compton Backscatter performance, we require that the electrons be injected to specified ring rf buckets and no others. The injector-linac electron gun is a single-cell s-band rf gun with a LaB6 cathode. The gun is followed by an a-magnet momentum filter and buncher. The LaB6 cathode can be operated in a pure thermionic mode, a laser switched photoemission mode, or in a combined mode. The laser is a near-UV TEA nitrogen laser with a 600 ps pulse, and 0-50 Hz repetition rate. We routinely inject 0.1 nC bunches at 270 MeV. The ratio of charge in the primary ring bucket to that in the other buckets is better than 1000.

  9. Spin decoherence in electron storage rings. More from a simple model

    Energy Technology Data Exchange (ETDEWEB)

    Barber, D.P. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Heinemann, K. [The Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Mathematics and Statistics

    2015-06-15

    This is an addendum to the paper ''Some models of spin coherence and decoherence in storage rings'' by one of the authors (K. Heinemann, DESY Report 97-166 (1997)), in which spin diffusion in simple electron storage rings is studied. In particular, we illustrate in a compact way, namely that the exact formalism of this article delivers a rate of depolarisation which can differ from that obtained by the conventional treatments of spin diffusion which rely on the use of the derivative ∂n/∂η. As a vehicle we consider a ring with a Siberian Snake and electron polarisation in the plane of the ring. For this simple setup with its one-dimensional spin motion, we avoid having to deal directly with the Bloch equation for the polarisation density. Our treatment, which is deliberately pedagogical, shows that the use of ∂n/∂η provides a very good approximation to the rate of spin depolarisation in the model considered. But it then shows that the exact rate of depolarisation can be obtained by replacing ∂n/∂η by another derivative, while giving a heuristic justification for the new derivative.

  10. Accurate correction of magnetic field instabilities for high-resolution isochronous mass measurements in storage rings

    CERN Document Server

    Shuai, P; Zhang, Y H; Litvinov, Yu A; Wang, M; Tu, X L; Blaum, K; Zhou, X H; Yuan, Y J; Audi, G; Yan, X L; Chen, X C; Xu, X; Zhang, W; Sun, B H; Yamaguchi, T; Chen, R J; Fu, C Y; Ge, Z; Huang, W J; Liu, D W; Xing, Y M; Zeng, Q

    2014-01-01

    Isochronous mass spectrometry (IMS) in storage rings is a successful technique for accurate mass measurements of short-lived nuclides with relative precision of about $10^{-5}-10^{-7}$. Instabilities of the magnetic fields in storage rings are one of the major contributions limiting the achievable mass resolving power, which is directly related to the precision of the obtained mass values. A new data analysis method is proposed allowing one to minimise the effect of such instabilities. The masses of the previously measured at the CSRe $^{41}$Ti, $^{43}$V, $^{47}$Mn, $^{49}$Fe, $^{53}$Ni and $^{55}$Cu nuclides were re-determined with this method. An improvement of the mass precision by a factor of $\\sim 1.7$ has been achieved for $^{41}$Ti and $^{43}$V. The method can be applied to any isochronous mass experiment irrespective of the accelerator facility. Furthermore, the method can be used as an on-line tool for checking the isochronous conditions of the storage ring.

  11. Ionization and Recombination Measurements at the Heidelberg Heavy Ion Storage Ring TSR

    Science.gov (United States)

    Savin, D. W.; Hahn, M.; Lestinsky, M.; Novonty, O.; Bernhardt, D.; Mueller, A.; Schippers, S.; Krantz, C.; Wolf, A.

    2011-05-01

    Reliable ionization balance calculations are needed to analyze spectra from a wide range of cosmic sources including photoionized objects such as AGNs and X-ray binaries and electron ionized objects such as as stars, supernovae, galaxies, and clusters of galaxies. These theoretical charge state distributions (CSD) depend in turn upon the underlying atomic data. Of particular importance are reliable rate coefficients for dielectronic recombination (DR), which is the dominant electron-ion recombination recombination mechanism for most ions, and for electron impact ionization (EII). We are carrying out DR and EII measurements of astrophysically important ions using the heavy ion Test Storage Ring (TSR) at the Max-Plank-Institute for Nuclear Physics in Heidelberg, Germany. The storage ring measurements are largely free of the metastable contamination found in other experimental geometries. Storage ring measurements therefore result in more precise DR and EII reaction rate measurements. The measured rate coefficients can be used in modeling cosmic and laboratory plasmas as well as in the benchmarking of theoretical atomic calculations. Here we report results for selected recent DR and EII measurements.

  12. Time structure measurement of the SSRF storage ring using TRXEOL method

    Institute of Scientific and Technical Information of China (English)

    张招红; 姜政; 薛松; 郑丽芳

    2015-01-01

    In order to do alignment between the timing signal and the synchrotron X-ray pulse on the sample spot in the time domain, measuring time structure of the storage ring on the sample spot inside the experimental hutch is a foundational step during the time-resolved experiments using the pulsed synchrotron X-rays with the time structure defined by the storage ring. In this work, the method of time-resolved X-ray excited optical luminescence (TRXEOL) was designed and implemented to do the measurement. It is based on the principle of time-correlated single photon counting techniques. The measurement system consists of a spectrometer with a detector of photomultiplier tube, a timing system, a set of nuclear instrument modules and a luminescent material of zinc oxide. The measurement was performed on the X-ray absorbed fine structure spectrum beamline at Shanghai Synchrotron Radiation Facility. The results show that this method can be used to measure the time structure of the storage ring with a precision of less than 1 ns. The measurement system can also be used for the time-resolved research for the optical luminescent materials.

  13. Simulation of spin dynamics to measure electric dipole moments in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, Marcel; Lehrach, Andreas [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik; Collaboration: JEDI-Collaboration

    2013-07-01

    CP violation in the baryon sector, which is predicted by the Standard Model of Particle Physics, is too small to explain the matter and antimatter asymmetry in our universe. Permanent Electric Dipole Moments (EDMs) violate both P and T symmetries and are therefore, through the CPT theorem, also CP violating. No direct EDM measurements for protons, deuterons and light nuclei have been performed up to now. The JEDI collaboration at Forschungszentrum Juelich (FZJ) and the BNL-EDM collaboration at Brookhaven National Laboratory (BNL) pursue the goal to measure the EDMs of these particles in dedicated storage rings. Therefore different approaches are studied to reach an ultimate sensitivity of 10{sup -29} e.cm. A first direct measurement of the proton and deuteron EDM at a sensitivity level of 10{sup -24} e.cm will be performed in the existing conventional storage ring at FZJ, the Cooler Synchrotron COSY. Particle tracking simulations to explore the motion-correlated spin dynamics are a crucial part of feasibility studies of the planned storage ring EDM experiments. In a first step, a benchmarking of simulation codes with measurements at the Cooler Synchrotron COSY is performed.

  14. Storage Rings in the Sky: Gamma Ray Bursts and Galactic Gravitational Collapse Stored Energy

    Science.gov (United States)

    Greyber, H. D.

    2004-05-01

    The recent discovery of almost 100% polarization of the prompt gamma ray emission from GRB021206, (1), confirms my 44 year old ``Strong" Magnetic Field" model (SMF) for galactic dynamics. In SMF, Storage Ring particles were accelerated long ago during the original gravitational collapse of the pregalactic/prequasar plasma cloud that is permeated by an almost uniform primordial magnetic field (2,3) The enormous, intense, slender, relativistic, stable, completely coherent Storage Ring stores a very small fraction of the huge galactic gravitational collapse energy in an almost radiationless state, unless disturbed. The concept of an Astrophysical Storage Ring was introduced by me in l961. At first it was to explain galactic structure, but soon it proved useful to explain active galactic nuclei (AGN) and the dynamics of quasar/AGN jets. AGN and galactic morphology, energetics and dynamics vary as the ratio of magnetic energy to rotational energy in the particular object. Gamma ray bursts (GRB) are due simply to a ``rock". i.e. a white dwarf, ordinary star, neutron sstar, asteroid, planet, etc. falling rapidly through the Storage Ring and being almost instantly vaporized into a hot plasma fireball, causing an electromagnetic shower (2) Then the fireball speeds into the huge organized magnetic field surrounding the current ring, thus generating very highly polarized prompt gamma ray emission (as seen in GRB021206) from the synchrotron radiation process. The timing fits the GRB observations nicely. For instance, a ``rock" racing at 1000 kilometers per second across a 20,000 km. path in the beam would produce a twenty second burst. Other times, a target might track across a short chord for a short burst. Space missions have shown that often typical currents in space plasmas are made up of slender filaments. Thus the puzzling less than one millisecond spikes observed in some GRB are simply describing the structure of that particular ring current at that particular time. 1

  15. Recommissioning of Duke Storage Ring with a HOM-Damped RF Cavity and a New Straight Section Lattice for FELs

    CERN Document Server

    Wu, Y K; Emamian, Mark; Faircloth, Joe; Gustavsson, J; Hartman, Steven M; Howell, C; Johnson, M; Li, Jingyi; Mikhailov, Stepan; Oakeley, Owen; Patterson, J; Pentico, Maurice; Popov, Victor; Rathbone, V; Swift, Gary; Wallace, Patrick W; Wang, Ping

    2005-01-01

    The Duke FEL lab operates a unique UV/VUV storage ring FEL and an FEL driven, nearly monochromatic, highly polarized, high intensity Compton gamma-ray source. The Duke storage ring light source is undergoing several phases of upgrade in order to significantly improve light source capabilities and performance. The 2004 phase included an upgrade of the RF system with a high-order mode damped RF cavity and a new 34 meter long straight section lattice to host new FEL wigglers in the next phase. This upgrade was completed in August 2004 and storage ring and light source commissioning were completed in November 2004. This paper will provide an overview of this upgrade project and report our commissioning experience of the storage ring and light sources.

  16. Spin motion at and near orbital resonance in storage rings with Siberian snakes I. At orbital resonance

    Energy Technology Data Exchange (ETDEWEB)

    Barber, D.P.; Vogt, M.

    2006-12-15

    Here, and in a sequel, we invoke the invariant spin field to provide an in-depth study of spin motion at and near low order orbital resonances in a simple model for the effects of vertical betatron motion in a storage ring with Siberian Snakes. This leads to a clear understanding, within the model, of the behaviour of the beam polarization at and near so-called snake resonances in proton storage rings. (orig.)

  17. Spin motion at and near orbital resonance in storage rings with Siberian Snakes. Part I: at orbital resonance

    CERN Document Server

    Barber, D P

    2006-01-01

    Here, and in a sequel, we invoke the invariant spin field to provide an in--depth study of spin motion at and near low order orbital resonances in a simple model for the effects of vertical betatron motion in a storage ring with Siberian Snakes. This leads to a clear understanding, within the model, of the behaviour of the beam polarisation at and near so--called snake resonances in proton storage rings.

  18. Present status of the NIJI-IV storage-ring free-electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, T.; Yamada, K.; Sei, N. [Electrotechnical Lab., Ibaraki (Japan)] [and others

    1995-12-31

    The tunable region of the free-electron-laser (FEL) wavelength with the NIJI-IV system is now 348{approximately}595 nm. After the lasing at 352 nm in 1994, the quality of the electron beam stored in the ring has been improved further, and the highest peak intensity of the laser obtained so far is more than 300 times as high as that of the resonated spontaneous emission. The macro-temporal structure of the lasing has been greatly improved. Recently, a single-bunch injection system was completed, and the system has been installed in the injector linac, which is expected to increase the peak stored-beam current. The commissioning and the test of the new system is under way. The beam transporting system from the linac to the ring is also being modified by increasing the number of quadrupole magnets. The experiments related to the FEL in the ultraviolet wavelength region will be begun in this coming May. The results and the status of the FEL experiments will be presented at the Conference.

  19. Towards the ultimate storage ring: The lattice design for Beijing Advanced Photon Source

    Institute of Scientific and Technical Information of China (English)

    XU Gang; JIAO Yi

    2013-01-01

    A storage ring-based light source,Beijing Advanced Photon Source (BAPS),is proposed to store a 5 GeV low-emittance electron beam and to provide high-brilliance coherent radiation.In this paper,we report our efforts of pushing down the emittance of BAPS to approach the so-called ultimate storage ring,while fixing the circumference to about 1200 m.To help deal with the challenge of beam dynamics associated with the intrinsic,very strong nonlinearities in an ultralow-emittance ring,a combination of several progressive technologies is used in the linear optics design and nonlinear optimization,such as a modified theoretical minimum emittance cell with smallaperture magnets,quasi-3rd-order achromat,theoretical analyzer based on Lie Algebra and Hamiltonian analysis,multi-objective genetic algorithm and frequency map analysis.These technologies enable us to obtain satisfactory beam dynamics in one lattice design with natural emittance of 75 pm.

  20. Diffraction-limited storage rings - a window to the science of tomorrow.

    Science.gov (United States)

    Eriksson, Mikael; van der Veen, J Friso; Quitmann, Christoph

    2014-09-01

    This article summarizes the contributions in this special issue on Diffraction-Limited Storage Rings. It analyses the progress in accelerator technology enabling a significant increase in brightness and coherent fraction of the X-ray light provided by storage rings. With MAX IV and Sirius there are two facilities under construction that already exploit these advantages. Several other projects are in the design stage and these will probably enhance the performance further. To translate the progress in light source quality into new science requires similar progress in aspects such as optics, beamline technology, detectors and data analysis. The quality of new science will be limited by the weakest component in this value chain. Breakthroughs can be expected in high-resolution imaging, microscopy and spectroscopy. These techniques are relevant for many fields of science; for example, for the fundamental understanding of the properties of correlated electron materials, the development and characterization of materials for data and energy storage, environmental applications and bio-medicine.

  1. THE POTENTIAL FOR NEUTRINO PHYSICS AT MUON COLLIDERS AND DEDICATED HIGH CURRENT MUON STORAGE RINGS

    Energy Technology Data Exchange (ETDEWEB)

    BIGI,I.; BOLTON,T.; FORMAGGIO,J.; HARRIS,D.; MORFIN,J.; SPENTZOURIS,P.; YU,J.; KAYSER,B.; KING,B.J.; MCFARLAND,K.; PETROV,A.; SCHELLMAN,H.; VELASCO,M.; SHROCK,R.

    2000-05-11

    Conceptual design studies are underway for both muon colliders and high-current non-colliding muon storage rings that have the potential to become the first true neutrino factories. Muon decays in long straight sections of the storage rings would produce uniquely intense and precisely characterized two-component neutrino beams--muon neutrinos plus electron antineutrinos from negative muon decays and electron neutrinos plus muon antineutrinos from positive muons. This article presents a long-term overview of the prospects for these facilities to greatly extend the capabilities for accelerator-based neutrino physics studies for both high rate and long baseline neutrino experiments. As the first major physics topic, recent experimental results involving neutrino oscillations have motivated a vigorous design effort towards dedicated neutrino factories that would store muon beams of energies 50 GeV or below. These facilities hold the promise of neutrino oscillation experiments with baselines up to intercontinental distances and utilizing well understood beams that contain, for the first time, a substantial component of multi-GeV electron-flavored neutrinos. In deference to the active and fast-moving nature of neutrino oscillation studies, the discussion of long baseline physics at neutrino factories has been limited to a concise general overview of the relevant theory, detector technologies, beam properties, experimental goals and potential physics capabilities. The remainder of the article is devoted to the complementary high rate neutrino experiments that would study neutrino-nucleon and neutrino-electron scattering and would be performed at high performance detectors placed as close as is practical to the neutrino production straight section of muon storage rings in order to exploit beams with transverse dimensions as small as a few tens of centimeters.

  2. Proposal of a relationship between dynamic aperture adn intensity evolution in a storage ring

    CERN Document Server

    Giovannozzi, M

    2010-01-01

    A scaling law for the time-dependence of the dynamic aperture, i.e., the region of phase space where stable motion occurs, was proposed in previous papers, about ten years ago. The use of fundamental theorems of the theory of dynamical systems allowed showing that the dynamic aperture has a logarithmic dependence on time. In this paper this result, proved by mean of numerical simulations, is used as a basis for deriving a scaling law for the intensity evolution in a storage ring. The proposed scaling law is also tested against experimental data showing a remarkable agreement.

  3. Linear optics calibration and nonlinear optimization during the commissioning of the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    TIAN Shun-Qiang; ZHANG Wen-Zhi; LI Hao-Hu; ZHANG Man-Zhou; HOU Jie; ZHOU xue-Mei; LIU Gui-Min

    2009-01-01

    Phase Ⅰ commissioning of the SSRF storage ring on 3.0 GeV beam energy was started at the end of December 2007.A lot of encouraging results have been obtained so far.In this paper,calibrations of the linear optics during the commissioning are discussed,and some measured results about the nonlinearity given.Calibration procedure emphasizes correcting quadrupole magnetic coefficients with the Linear Optics from Closed Orbit(LOCO)technique.After fitting the closed orbit response matrix,the linear optics of the four test modes is substantially corrected,and the measured physical parameters agree well with the designed ones.

  4. Study of closed orbit response to magnet vibrations at the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-Hui; ZHAO Zhen-Tang; DAI Zhi-Min; LIU Gui-Min

    2008-01-01

    This paper presents the analytical and simulation responses of the closed orbit distortion in the SSRF storage ring to random and plane wave like magnet vibrations respectively. It is shown that the use of girder is very beneficial in the view of suppressing this response function. Effect of the independently supported gradient bending magnets to the closed orbit response is given. An analytic formula is written to give a rough estimate of the closed orbit distortion due to ground motion, taking into account the closed orbit response function and girder transfer function. As an example, the result of SSRF case is given.

  5. Proposal to detect an emission of unusual super-high energy electrons in electron storage rings

    Directory of Open Access Journals (Sweden)

    Da-peng Qian

    2014-01-01

    Full Text Available According to an extended Lorentz–Einstein mass formula taken into the uncertainty principle, it is predicted that the electron beams passing accelerating electric field should with a small probability generate abnormal super-high energy electrons which are much higher than the beam energy. Author’s preliminary experiment result at electron storage ring has hinted these signs, so suggests to more strictly detect this unusual phenomenon, and thus to test the extended mass formula as well as a more perfect special relativity.

  6. Design of the beam transport line and injection system of the compact storage ring for TTX

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In this article, we present the design of the beam transport line and injection system of the compact storage ring for the Tsinghua Thomson scattering X-ray (TTX) source. The layout of the beam transport line fits in with the limited available space. The injection system is simplified, consisting of only one single kicker; the stray field on the reference orbit is also reduced without the septum magnet. We choose a travelling wave kicker and present both 2D and 3D simulations for the structure design.

  7. Probing the violation of equivalence principle at a muon storage ring via neutrino oscillation

    CERN Document Server

    Datta, A

    2001-01-01

    We examine the possible tests of violation of the gravitational equivalence principle (VEP) at a muon storage ring via neutrino oscillation experiments. If different neutrino flavours couple to the gravitational potential with different strength, flavour eigenstates are no longer the gravitational interaction eigenstates. This leads to the neutrino oscillation. If one starts with $\\mu ^+$ beam then appearance of $\\tau ^\\pm$, $e ^+$ and $\\mu ^-$ in the final state are the signals for neutrino oscillation. We have estimated the number of $\\mu ^-$ and $\\tau^+$ events in this scenario in $\

  8. Characteristics of the Duke/OK-4 storage ring FEL and gamma-ray source

    Science.gov (United States)

    Park, Seong Hee

    The Duke/OK-4 storage ring is a dedicated device for driving a short wavelength Free Electron Laser (FEL). In addition, Compton scattering of the laser light from the circulating electron beam products a semi-monochromatic γ-ray source. The dynamics of such a system including accelerator physics, FEL physics, and Compton backscattering is complex and requires special study, This dissertation is a detailed theoretical and experimental analysis of such a system. The main emphasis of the theory presented here is the self-consistent analysis of the system which incorporates three drastically different processes-the dynamics of an intense electron beam, the free electron laser, and the Compton backscattering. The interdependence of these three processes and the physics of this complex system is discussed in this work. The OK-4/Duke storage ring FEL is the only accelerator facility capable of routine lasing in the deep-UV range and able to generate intense γ-ray beams with energy tunable from 2 MeV to 55 MeV, with energy resolution between 0.5%-1% and with flux up to -5 × 107. The flexibility of this γ-ray source is due to the record-breaking performance of the OK-4/Duke storage ring FEL (lasing from 193.7 nm to 730 nm). Experimental studies determining the parameters of the electron beams, OK-4 FEL beams, and γ-ray beams compare favorably with the theoretical predictions. This study confirms that the electron energy spread induced by FEL lasing is currently the main factor limiting energy resolution. These results provide a solid foundation for future development of the system to obtain more reliable predictions of its performance. A number of useful ``scaling laws'' are also presented here. The results of this work have provided the basis for a number of applications of the OK-4 FEL beam and γ- ray beam that are underway or in the advance planning stage. Future plans include the development and design of a system capable of generating γ-ray beams with an energy

  9. Rf stability, control and bunch lengthening in electron synchrotron storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Wachtel, J.M.

    1989-09-01

    A self-consistent theory for nonlinear longitudinal particle motion and rf cavity excitation in a high energy electron storage ring is developed. Coupled first order equations for the motion of an arbitrary number of particles and for the field in several rf cavities are given in the form used in control system theory. Stochastic quantum excitation of synchrotron motion is included, as are the effects of rf control system corrections. Results of computations for double cavity bunch lengthening are given. 11 refs., 4 figs., 1 tab.

  10. Safe operating conditions for NSLS-II Storage Ring Frontends commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Seletskiy, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Amundsen, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ha, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hussein, A. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-04-02

    The NSLS-II Storage Ring Frontends are designed to safely accept the synchrotron radiation fan produced by respective insertion device when the electron beam orbit through the ID is locked inside the predefined Active Interlock Envelope. The Active Interlock is getting enabled at a particular beam current known as AI safe current limit. Below such current the beam orbit can be anywhere within the limits of the SR beam acceptance. During the FE commissioning the beam orbit is getting intentionally disturbed in the particular ID. In this paper we explore safe operating conditions for the Frontends commissioning.

  11. Intensity interferometry of single x-ray pulses from a synchrotron storage ring

    CERN Document Server

    Singer, A; Marras, A; Klyuev, A; Becker, J; Schlage, K; Skopintsev, P; Gorobtsov, O; Shabalin, A; Wille, H -C; Franz, H; Graafsma, H; Vartanyants, I A

    2014-01-01

    We report on measurements of second-order intensity correlations at the high brilliance storage ring PETRA III using a prototype of the newly developed Adaptive Gain Integrating Pixel Detector (AGIPD). The detector recorded individual synchrotron radiation pulses with an x-ray photon energy of 14.4 keV and repetition rate of about 5 MHz. The second-order intensity correlation function was measured simultaneously at different spatial separations that allowed to determine the transverse coherence length at these x-ray energies. The measured values are in a good agreement with theoretical simulations based on the Gaussian Schell-model.

  12. Th.P-19. Collisional effects and dynamic aperture in high-intensity storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Benedetti, C. [Dipartimento di Fisica Universita di Bologna and INFN, Via Irnerio 46, Bologna 40126 (Italy)]. E-mail: benedetti@bo.infn.it; Rambaldi, S. [Dipartimento di Fisica Universita di Bologna and INFN, Via Irnerio 46, Bologna 40126 (Italy); Turchetti, G. [Dipartimento di Fisica Universita di Bologna and INFN, Via Irnerio 46, Bologna 40126 (Italy)

    2005-05-21

    We analyze the dynamic aperture in the presence of strong sextupolar errors for a high-intensity beam. The scaling laws for the short-term dynamic aperture are examined and its dependence on the perveance is discussed in a mean field approximation for a coasting beam. The collisional effects of Coulombian interaction are estimated for a linear lattice using a scaling law for the relaxation time. The collisional effects on the long-time dynamic aperture are discussed by comparing the results of full Hamiltonian integration with a mean field theory. An application to a storage ring with the HIDIF parameters is briefly outlined.

  13. Addenda to General Spin Precession and Betatron Oscillation in Storage Ring

    CERN Document Server

    Fukuyama, Takeshi

    2016-01-01

    We give the geralized expression of spin precession of extended bunch particles having both anomalous magnetic and electric dipole moments in storage ring in higher order than the previous work and in the presence of ${\\bf E}$ field as well as ${\\bf B}$ field. These addenda are essential since some experiments consider the focusing field in the second order of the beam extent and in the presence of both ${\\bf B}$ and ${\\bf E}$ fields . It is shown that some focusing fields with constant magnitude of the velocity considered in many literatures lead to the violation of self consistency.

  14. An MDM Spin Transparent Quadrupole for Storage Ring based EDM Search

    CERN Document Server

    Bai, Mei; Sagan, David

    2016-01-01

    A storage ring provides an attractive option for directly measuring the electric dipole moment~(EDM) of charged particles. To reach a sensitivity of 10^-29 e x cm, it is critical to mitigate the systematic errors from all sources. This daunting task is pushing the precision frontier of accelerator science and technology beyond its current state of the art. Here, we present a unique idea of a magnetic dipole moment~(MDM) spin transparent quadrupole that can significantly reduce the systematic errors due to the transverse electric and magnetic fields that particle encounters.

  15. Commissioning and Early Operation Experience of the NSLS-II Storage Ring RF System

    Energy Technology Data Exchange (ETDEWEB)

    Gao, F.; Rose, J.; Cupolo, J.; Dilgen, T.; Rose, B.; Gash, W.; Ravindranath, V.; Yeddulla, M.; Papu, J.; Davila, P.; Holub, B.; Tagger, J.; Sikora, R.; Ramirez, G.; Kulpin, J.

    2015-05-03

    The National Synchrotron Light Source II (NSLS-II) is a 3 GeV electron X-ray user facility commissioned in 2014. The storage ring RF system, essential for replenishing energy loss per turn of the electrons, consists of digital low level RF controllers, 310 kW CW klystron transmitters, CESR-B type superconducting cavities, as well as a supporting cryogenic system. Here we will report on RF commissioning and early operation experience of the system for beam current up to 200mA.

  16. Beam dynamics studies on BEPC-Ⅱstorage rings at the commissioning stage

    Institute of Scientific and Technical Information of China (English)

    QIN Qing; HUANG Nan; LIU Wei-Bin; LIU Yu-Dong; PENG Yue-Mei; QIU Jing; WANG Dou; WANG Xin-Hao; WANG Na; WANG Jiu-Qing; WEI Yuan-Yuan; WEN Xue-Mei; XING Jun; XU Gang; Yu Cheng-Hui; ZHANG Chuang; ZHANG Yuan; ZHAO Zheng; ZHOU De-Min

    2009-01-01

    During the 1st and 2nd stages of the commissioning of the upgrade project of the Beijing Electron Positron Collider(BEPC Ⅱ),which started on Nov.12,2006 and Oct.24,2007,respectively,we got the luminosity one tenth of its design value,provided beams to synchrotron radiation users for about 4 months,and studied beam dynamics as well.In this paper,some beam dynamics studies on the storage rings and their preliminary results are given.

  17. Recent Results and Progress on Leptonic and Storage Ring EDM Searches

    Science.gov (United States)

    Kawall, David

    2016-02-01

    The Standard Model is incomplete and unable to explain the matter-antimatter asymmetry in the universe. Many extensions of the Standard Model predict new particles and interactions with additional CP-violating phases that can explain this imbalance. Electric dipole moments (EDMs) of fundamental particles, which are generated by CP-violating interactions, can be enhanced by many orders of magnitude by contributions from this new physics to a magnitude within reach of current and planned experiments. New approaches to EDM searches using storage rings, and their sensitivity to new physics are presented.

  18. Restriction on the energy and luminosity of e(+)e(-) storage rings due to beamstrahlung.

    Science.gov (United States)

    Telnov, V I

    2013-03-15

    The role of beamstrahlung in high-energy e(+)e(-) storage-ring colliders (SRCs) is examined. Particle loss due to the emission of single energetic beamstrahlung photons is shown to impose a fundamental limit on SRC luminosities at energies 2E(0)≳140  GeV for head-on collisions and 2E(0)≳40  GeV for crab-waist collisions. With beamstrahlung taken into account, we explore the viability of SRCs in the 2E(0)=240-500   GeV range, which is of interest in the precision study of the Higgs boson. At 2E(0)=240  GeV, SRCs are found to be competitive with linear colliders; however, at 2E(0)=400-500  GeV, the attainable SRC luminosity would be a factor 15-25 smaller than desired.

  19. The HERMES Polarized Hydrogen and Deuterium Gas Target in the HERA Electron Storage Ring

    CERN Document Server

    Airapetian, A; Akopov, Z; Amarian, M; Ammosov, V V; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Baturin, V; Baumgarten, C; Beckmann, M; Belostotskii, S; Bernreuther, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Bouwhuis, M; Brack, J; Brüll, A; Bryzgalov, V V; Capitani, G P; Chiang, H C; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; De Leo, R; De Nardo, L; De Sanctis, E; Devitsin, E G; Di Nezza, P; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G M; Ellinghaus, F; Elschenbroich, U; Ely, J; Fabbri, R; Fantoni, A; Feshchenko, A; Felawka, L; Fox, B; Franz, J; Frullani, S; Gärber, Y; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Garutti, E; Gaskell, D; Gavrilov, G E; Karibian, V; Graw, G; Grebenyuk, O; Greeniaus, L G; Hafidi, K; Hartig, M; Hasch, D; Heesbeen, D; Henoch, M; Hertenberger, R; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Kinney, E; Kiselev, A; Königsmann, K C; Kopytin, M; Korotkov, V A; Kozlov, V; Krauss, B; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Laziev, A; Lenisa, P; Liebing, P; Lindemann, T; Lipka, K; Lorenzon, W; Lü, J; Maiheu, B; Makins, N C R; Marianski, B; Marukyan, H O; Masoli, F; Mexner, V; Meyners, N; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Nass, A; Negodaev, M A; Nowak, Wolf-Dieter; Oganessyan, K; Ohsuga, H; Orlandi, G; Pickert, N; Potashov, S Yu; Potterveld, D H; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubacek, L; Ryckbosch, D; Salomatin, Yu I; Sanjiev, I; Savin, I; Scarlett, C; Schäfer, A; Schill, C; Schnell, G; Schüler, K P; Schwind, A; Seele, J; Seidl, R; Seitz, B; Shanidze, R G; Shearer, C; Shibata, T A; Shutov, V B; Simani, M C; Sinram, K; Stancari, M D; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Stösslein, U; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Tkabladze, A V; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Vetterli, Martin C; Vikhrov, V; Vincter, M G; Visser, J; Vogel, C; Vogt, M; Volmer, J; Weiskopf, C; Wendland, J; Wilbert, J; Ybeles-Smit, G V; Yen, S; Zihlmann, B; Zohrabyan, H G; Zupranski, P

    2004-01-01

    The HERMES hydrogen and deuterium nuclear-polarized gas targets have been in use since 1996 with the polarized electron beam of HERA at DESY to study the spin structure of the nucleon. Polarized atoms from a Stern-Gerlach Atomic Beam Source are injected into a storage cell internal to the HERA electron ring. Atoms diffusing from the center of the storage cell into a side tube are analyzed to determine the atomic fraction and the atomic polarizations. The atoms have a nuclear polarization, the axis of which is defined by an external magnetic holding field. The holding field was longitudinal during 1996-2000, and was changed to transverse in 2001. The design of the target is described, the method for analyzing the target polarization is outlined, and the performance of the target in the various running periods is presented.

  20. A PULSED MODULATOR POWER SUPPLY FOR THE G-2 MUON STORAGE RING INJECTION KICKER.

    Energy Technology Data Exchange (ETDEWEB)

    MI,J.LEE,Y.Y.MORSE,W.M.PAI,C.I.PAPPAS,G.C.SANDERS,Y.SEMERTIZIDIS,Y.,ET AL.

    2003-03-01

    This paper describes the pulse modulator power supplies used to drive the kicker magnets that inject the muon beam into the 8-2 storage ring that has been built at Brookhaven National Laboratory. Three modulators built into coaxial structures consisting of a series circuit of an energy storage capacitor, a damping resistor and a fast thyratron switch are used to energize three magnets that kick the beam into the proper orbit. A 100 kV charging power supply is used to charge the capacitor to 95kV. The damping resistor shapes the magnet current waveform to a 450 nanosecond half-sine to match the injection requirements. This paper discusses the modulator design, construction and operation.

  1. Deposition of robust multilayer mirror coatings for storage ring FEL lasing at 176nm

    Science.gov (United States)

    Günster, St.; Ristau, D.; Trovó, M.; Danailov, M.; Gatto, A.; Kaiser, N.; Sarto, F.; Piegari, A.

    2005-09-01

    Progress was achieved in the last years in the development of multilayer mirrors used in storage ring Free Electron Lasers (FEL) operating in the vacuum ultraviolet spectral range. Based on dense oxide coatings deposited by Ion Beam Sputtering, a stable lasing at 190 nm was demonstrated. The extension towards shorter wavelengths had to overcome severe problems connected to the radiation resistance and the necessary reflectivity of the resonator mirrors. In this context, radiation resistance can be considered as the ability of the mirror materials to withstand the high power laser radiation and the intense energetic background radiation generated in the synchrotron source. The bombardment with high energetic photons leads to irreversible changes and a coloration on the specimen. Reflectivity requirements can be evaluated from the tolerable losses of FEL systems. At ELETTRA FEL the resonator mirror reflectivity must be above 95 %. Evaporated fluoride multilayer mirrors provide sufficient reflectivity, but they do not exhibit an adequate radiation resistance. Pure oxide multilayers show a sufficient radiation resistance, but they cannot reach the necessary reflectivity below 190 nm. A successful approach combines evaporated fluoride multilayer stack with a dense protection layer of silicon dioxide deposited by Ion Beam Sputtering. Such mirror systems were produced reaching a reflectivity of approximately 99 % at 180 nm. Lasing in the storage ring FEL at ELETTRA was realised in the range between 176 - 179 nm. The mirror reflectivity shows only a slight degradation after lasing, which could be fully restored after the lasing experiment.

  2. A single particle detector for electron-ion collision experiments in the Cryogenic Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Spruck, Kaija; Mueller, Alfred; Schippers, Stefan [Institut fuer Atom- und Molekuelphysik, Justus-Liebig-Universitaet Giessen (Germany); Krantz, Claude; Becker, Arno; Vogel, Stephen; Wolf, Andreas [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Novotny, Oldrich [Columbia Astrophysics Laboratory, New York (United States)

    2014-07-01

    The study of ion chemistry in the interstellar medium requires, among others, knowledge about cross sections for the recombination of atomic and molecular ions with low temperature (∝10 K) electrons. Especially the database on singly charged atomic ions relevant to the chemistry of molecular clouds is incomplete in this respect. The electrostatic Cryogenic Storage Ring (CSR), currently being commissioned at the Max-Planck-Institute for Nuclear Physics in Heidelberg, will allow experiments with atomic, molecular and cluster ions at beam energies up to 300 keV per unit charge in a cryogenic extremely high vacuum (XHV) environment. Collisions of stored atomic ions with electrons provided by an electron cooler will lead to reaction products with charge states that differ from those of the parent particles. The detection of these products will be carried out behind a bending deflector of the storage ring by a high-efficiency movable single-particle detector, based on a secondary electron converter backed by heatable microchannel plates. The designs of the mechanical actuator and the detector are compatible with the cryogenic operating conditions at 10 K and a bakeout temperature of up to 530 K.

  3. Study of magnetic hysteresis effects in a storage ring using precision tune measurement

    Science.gov (United States)

    Li, Wei; Hao, Hao; Mikhailov, Stepan F.; Xu, Wei; Li, Jing-Yi; Li, Wei-Min; Wu, Ying. K.

    2016-12-01

    With the advances in accelerator science and technology in recent decades, the accelerator community has focused on the development of next-generation light sources, for example diffraction-limited storage rings (DLSRs), which require precision control of the electron beam energy and betatron tunes. This work is aimed at understanding magnet hysteresis effects on the electron beam energy and lattice focusing in circular accelerators, and developing new methods to gain better control of these effects. In this paper, we will report our recent experimental study of the magnetic hysteresis effects and their impacts on the Duke storage ring lattice using the transverse feedback based precision tune measurement system. The major magnet hysteresis effects associated with magnet normalization and lattice ramping are carefully studied to determine an effective procedure for lattice preparation while maintaining a high degree of reproducibility of lattice focusing. The local hysteresis effects are also studied by measuring the betatron tune shifts which result from adjusting the setting of a quadrupole. A new technique has been developed to precisely recover the focusing strength of the quadrupole by returning it to a proper setting to overcome the local hysteresis effect. Supported by National Natural Science Foundation of China (11175180, 11475167) and US DOE (DE-FG02-97ER41033)

  4. Quasiperiodic spin-orbit motion and spin tunes in storage rings

    CERN Document Server

    Barber, D P; Heinemann, K

    2004-01-01

    We present an in-depth analysis of the concept of spin precession frequency for integrable orbital motion in storage rings. Spin motion on the periodic closed orbit of a storage ring can be analyzed in terms of the Floquet theorem for equations of motion with periodic parameters and a spin precession frequency emerges in a Floquet exponent as an additional frequency of the system. To define a spin precession frequency on nonperiodic synchro-betatron orbits we exploit the important concept of quasiperiodicity. This allows a generalization of the Floquet theorem so that a spin precession frequency can be defined in this case too. This frequency appears in a Floquet-like exponent as an additional frequency in the system in analogy with the case of motion on the closed orbit. These circumstances lead naturally to the definition of the uniform precession rate and a definition of spin tune. A spin tune is a uniform precession rate obtained when certain conditions are fulfilled. Having defined spin tune we define sp...

  5. Characteristics Of The Duke/ok-4 Storage Ring Fel And Gamma-ray Source

    CERN Document Server

    Park, S H

    2000-01-01

    The Duke/OK-4 storage ring is a device for driving a short wavelength Free Electron Laser (FEL). In addition, Compton scattering of the laser light from the circulating electron beam products a semi-monochromatic γ-ray source. The dynamics of such a system including accelerator physics, FEL physics, and Compton backscattering is complex and requires special study, This dissertation is a detailed theoretical and experimental analysis of such a system. The main emphasis of the theory presented here is the self-consistent analysis of the system which incorporates three drastically different processes—the dynamics of an intense electron beam, the free electron laser, and the Compton backscattering. The interdependence of these three processes and the physics of this complex system is discussed in this work. The OK-4/Duke storage ring FEL is the only accelerator facility capable of routine lasing in the deep-UV range and able to generate intense γ-ray beams with energy tunable from 2 ...

  6. CESAR, 2 MeV electron storage ring; general view from above.

    CERN Multimedia

    Service Photo

    1967-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  7. Measurement and Compensation of Horizontal Crabbing at the Cornell Electron Storage Ring Test Accelerator

    CERN Document Server

    Ehrlichman, M P; Hartung, W; Peterson, D P; Rider, N; Rubin, D; Sagan, D; Shanks, J P; Wang, S T

    2013-01-01

    In storage rings, horizontal dispersion in the rf cavities introduces horizontal-longitudinal ($xz$) coupling, contributing to beam tilt in the $xz$ plane. This coupling can be characterized by a "crabbing" dispersion term $\\zeta_a$ that comes from decomposing the $1$-turn transfer matrix. $\\zeta_a$ is proportional to the rf cavity voltage and the horizontal dispersion in the cavity. We report experiments at the Cornell Electron Storage Ring Test Accelerator (CesrTA) where $xz$ coupling was explored using three lattices with distinct crabbing properties. We characterize the $xz$ coupling for each case by measuring the horizontal projection of the beam with a beam size monitor. The three lattice configurations correspond to a) $16$ mrad $xz$ tilt at the beam size monitor source point, b) compensation of the $\\zeta_a$ introduced by one of two pairs of RF cavities with the second, and c) zero dispersion in RF cavities, eliminating $\\zeta_a$ entirely. Additionally, intrabeam scattering (IBS) is evident in our mea...

  8. Use of the Halbach perturbation theory for the multipole design of the ALS storage ring sextupole

    Energy Technology Data Exchange (ETDEWEB)

    Marks, S. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    The Advanced Light Source (ALS) storage ring sextupole is a unique multi-purpose magnet. It is designed to operate in the primary or sextupole mode and in three auxiliary trim modes: horizontal steering, vertical steering, and skew quadrupole. Klaus Halbach developed a perturbation theory for iron-dominated magnets which provides the basis for this design. Many magnet designers, certainly those who have been exposed to Klaus, are familiar with this theory and have used it for such things as evaluating the effect of assembly alignment errors. The ALS sextupole design process was somewhat novel in its use of the perturbation theory to design essential features of the magnet. In particular, the steering and skew quadrupole functions are produced by violating sextupole symmetry and are thus perturbations of the normal sextupole excitation. The magnet was designed such that all four modes are decoupled and can be excited independently. This paper discusses the use of Halbach`s perturbation theory to design the trim functions and to evaluate the primary asymmetry in the sextupole mode, namely, a gap in the return yoke to accommodate the vacuum chamber. Prototype testing verified all operating modes of the magnet and confirmed the expected performance from calculations based upon the Halbach perturbation theory. A total of 48 sextupole magnets of this design are now installed and operating successfully in the ALS storage ring.

  9. Design, Modeling and Control of Magnetic Bearings for a Ring-Type Flywheel Energy Storage System

    Directory of Open Access Journals (Sweden)

    Chow-Shing Toh

    2016-12-01

    Full Text Available This study is concerned with the magnetic force models of magnetic bearing in a flywheel energy storage system (FESS. The magnetic bearing is of hybrid type, with axial passive magnetic bearing (PMB and radial hybrid magnetic bearing (HMB. For the PMB, a pair of ring-type Halbach arrays of permanent magnets are arranged vertically to support the rotor weight. For the HMB, a set of ring-type Halbach array is placed on the rotor side, which corresponds to coil sets on the stator side. The HMB can produce both attraction and repulsion forces on the radial direction, depending on the direction of the coil currents. It is found that the ring-type configuration and the differential winding scheme for coil sets can yield linear magnetic force models for both PMB and HMB. Based on the obtained magnetic force model, an integral sliding mode controller is designed for the stable rotor levitation in the radial direction. The experimental results show that the rotor can be stabilized to the bearing center, verifying the accuracy of the magnetic force models and effectiveness of the levitation controller.

  10. Coherent modes for multiple non-rigid bunches in a storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Berg, J.S.

    1996-03-01

    A method is presented for determining the stability of a system consisting of several highly relativistic bunches of charged particles circulating in a storage ring. The particles interact with magnets designed to guide the beam as well as with electromagnetic fields induced by the particles themselves. Previous work has considered modes where all bunches in the ring are executing the same type of internal oscillation. This dissertation considers the results of allowing those modes to couple to one another. The formalism begins with a self-consistent distribution, and analyzes small perturbations to that distribution to determine if they grow exponentially. The formalism allows one to do this computation for an arbitrary magnetic lattice, as well as an arbitrary distribution of wakefield sources around the ring. The method also allows for the inclusion of a feedback system which is designed to damp multibunch oscillations. The PEP-II B-factory with a linear lattice is used as an example to demonstrate and explain the phenomenology that results from this coupling of multibunch modes. The effect of adding feedback is also explored.

  11. Radicals in Berkeley?

    Science.gov (United States)

    Linn, Stuart

    2015-04-03

    In a previous autobiographical sketch for DNA Repair (Linn, S. (2012) Life in the serendipitous lane: excitement and gratification in studying DNA repair. DNA Repair 11, 595-605), I wrote about my involvement in research on mechanisms of DNA repair. In this Reflections, I look back at how I became interested in free radical chemistry and biology and outline some of our bizarre (at the time) observations. Of course, these studies could never have succeeded without the exceptional aid of my mentors: my teachers; the undergraduate and graduate students, postdoctoral fellows, and senior lab visitors in my laboratory; and my faculty and staff colleagues here at Berkeley. I am so indebted to each and every one of these individuals for their efforts to overcome my ignorance and set me on the straight and narrow path to success in research. I regret that I cannot mention and thank each of these mentors individually.

  12. Lattice Design for PEP-X Ultimate Storage Ring Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Bane, K.L.F.; Cai, Y.; Nosochkov, Y.; Wang, M.-H.; /SLAC; Hettel, R.O.; /SLAC

    2011-12-13

    SLAC expertise in designing and operating high current storage rings and the availability of the 2.2-km PEP-II tunnel present an opportunity for building a next generation light source - PEP-X - that would replace the SPEAR3 storage ring in the future. The PEP-X 'baseline' design, with 164 pm-rad emittance at 4.5 GeV beam energy and a current of 1.5 A, was completed in 2010. As a next step, a so-called 'ultimate' PEP-X lattice, reducing the emittance to 11 pm-rad at zero current, has been designed. This emittance approaches the diffraction limited photon emittance for multi-keV photons, providing near maximum photon brightness and high coherence. It is achieved by using 7-bend achromat cells in the ring arcs and a 90-m damping wiggler in one of the 6 long straight sections. Details of the lattice design, dynamic aperture, and calculations of the intra-beam scattering effect and Touschek lifetime at a nominal 0.2 A current are presented. Accelerator-based light sources are in high demand for many experimental applications. The availability of the 2.2-km PEP-II tunnel at SLAC presents an opportunity for building a next generation light source - PEP-X - that would replace the existing SPEAR3 light source in the future. The PEP-X study started in 2008, and the 'baseline' design, yielding 164 pm-rad emittance at 4.5 GeV beam energy and a current of 1.5 A, was completed in 2010. This relatively conservative design can be built using existing technology. However, for a long term future, it is natural to investigate a more aggressive, so-called 'ultimate' ring design. The goal is to reduce the electron emittance in both x and y planes to near the diffraction limited photon emittance of 8 pm-rad at hard X-ray photon wavelength of 0.1 nm. This would provide a near maximum photon brightness and significant increase in photon coherence. This study was motivated by the advances in low emittance design at MAX-IV. The latter was used as a

  13. Simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    CERN Document Server

    Yang, Xi

    2015-01-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. The method has been successfully demonstrated on the NSLS-II storage ring.

  14. LIGHT SOURCE: Optics for the lattice of the compact storage ring for a Compton X-ray source

    Science.gov (United States)

    Yu, Pei-Cheng; Wang, Yu; Shen, Xiao-Zhe; Huang, Wen-Hui; Yan, Li-Xin; Du, Ying-Chao; Li, Ren-Kai; Tang, Chuan-Xiang

    2009-06-01

    We present two types of optics for the lattice of a compact storage ring for a Compton X-ray source. The optics design for different operation modes of the storage ring are discussed in detail. For the pulse mode optics, an IBS-suppression scheme is applied to optimize the optics for lower IBS emittance growth rate; as for the steady mode, the method to control momentum compact factor is adopted [Gladkikh P, Phys. Rev. ST Accel. Beams 8, 050702] to obtain stability of the electron beam.

  15. Proceedings of the 1979 workshop on beam current limitations in storage rings, July 16-27, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, C. (ed.)

    1979-01-01

    The Workshop on Beam Current Limitations in Storage Rings was held at Brookhaven National Laboratory from July 16 to 27, 1979. The purpose of this Workshop was to discuss the physical mechanisms limiting the beam current or current density in accelerators or storage rings. Many of these machines are now being built or planned for a variety of applications, such as colliding beam experiments, synchrotron light production, heavy ion beams. This diversity was reflected in the Workshop and in the papers which have been contributed to these Proceedings. The twenty-one papers from the workshop were incorporated individually in the data base. (GHT)

  16. Application of FEL technique for constructing high-intensity, monochromatic, polarized gamma-sources at storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Saldin, E.L.; Schneidmiller, E.A.; Ulyanov, Yu.N. [Automatic Systems Corporation, Samara (Russian Federation)] [and others

    1995-12-31

    A possibility to construct high-intensity tunable monochromatic{gamma}-source at high energy storage rings is discussed. It is proposed to produce {gamma}-quanta by means of Compton backscattering of laser photons on electrons circulating in the storage. The laser light wavelength is chosen in such a way that after the scattering, the electron does not leave the separatrix. So as the probability of the scattering is rather small, energy oscillations are damped prior the next scattering. As a result, the proposed source can operate in {open_quotes}parasitic{close_quote} mode not interfering with the main mode of the storage ring operation. Analysis of parameters of existent storage rings (PETRA, ESRF, Spring-8, etc) shows that the laser light wavelength should be in infrared, {lambda}{approximately} 10 - 400 {mu}m, wavelength band. Installation at storage rings of tunable free-electron lasers with the peak and average output power {approximately} 10 MW and {approximately} 1 kW, respectively, will result in the intensity of the {gamma}-source up to {approximately} 10{sup 14}s{sup -1} with tunable {gamma}-quanta energy from several MeV up to several hundreds MeV. Such a {gamma}-source will reveal unique possibilities for precision investigations in nuclear physics.

  17. Klystron 'efficiency loop' for the ALS storage ring RF system

    Energy Technology Data Exchange (ETDEWEB)

    Kwiatkowski, Slawomir; Julian, Jim; Baptiste, Kenneth

    2002-05-20

    The recent energy crisis in California has led us to investigate the high power RF systems at the Advanced Light Source (ALS) in order to decrease the energy consumption and power costs. We found the Storage Ring Klystron Power Amplifier system operating as designed but with significant power waste. A simple proportional-integrator (PI) analog loop, which controls the klystron collector beam current, as a function of the output RF power, has been designed and installed. The design considerations, besides efficiency improvement, were to interface to the existing system without major expense. They were to also avoid the klystron cathode power supply filter's resonance in the loop's dynamics, and prevent a conflict with the existing Cavity RF Amplitude Loop dynamics. This efficiency loop will allow us to save up to 700 MW-hours of electrical energy per year and increase the lifetime of the klystron.

  18. Beam lifetime measurement and analysis in Indus-2 electron storage ring

    Indian Academy of Sciences (India)

    Pradeep Kumar; A D Ghodke; Gurnam Singh

    2013-05-01

    In this paper, the beam lifetime measurement and its theoretical analysis are presented using measured vacuum pressure and applied radio frequency (RF) cavity voltage in Indus-2 electron storage ring at 2 GeV beam energy. Experimental studies of the effect of RF cavity voltage and bunched beam filling pattern on beam lifetime are also presented. An equation of stable beam current decay is evolved and this equation closely follows the observed beam current decay pattern. It shows that the beam is stable and the beam current decay is due to the beam–residual gas interaction (vacuum lifetime) and electron–electron interaction within a bunch (Touschek lifetime). The estimated vacuum, Touschek and total beam lifetimes from analytical formulations are also compared with the measured beam lifetime.

  19. Lattice design and optimization for the PEP-X ultra low emittance storage ring at SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Min-Huey; Nosochkov, Yuri; Bane, Karl; Cai, Yunhai; Hettel, Robert; Huang, Xiaobiao; /SLAC

    2011-08-12

    SLAC is developing a long-range plan to transfer the evolving scientific programs at SSRL from the SPEAR3 light source to a much higher performing photon source. One of the possibilities is a new PEP-X 4.5 GeV storage ring that would be housed in the 2.2 km PEP-II tunnel. The PEP-X is designed to produce photon beams having brightness near 10{sup 22} (ph/s/mm{sup 2}/mrad{sup 2}/0.1% BW) at 10 keV with 3.5 m undulator at beam current of 1.5 A. This report presents an overview of the PEP-X baseline lattice design and describes the lattice optimization procedures in order to maximize the beam dynamic aperture. The complete report of PEP-X baseline design is published in SLAC report.

  20. The Heidelberg High Current Injector A Versatile Injector for Storage Ring Experiments

    CERN Document Server

    Von Hahn, R; Repnow, R; Schwalm, D; Welsch, C P

    2004-01-01

    The High Current Injector (HCI) was designed and built as a dedicated injector for the Test Storage Ring in Heidelberg to deliver mainly singly charged Li- and Be-ions. After start for routine operation in 1999 the HCI delivered stable beams during the following years for about 50 % of the experiments with very high reliability. Due to the requirements from the experiment the HCI changed during that period from a machine for singly charged positive ions to an injector for a large variety of molecules as well as positively or negatively charged light ions. After successful commissioning of the custom built 18 GHz high power ECR-source at its present test location various modifications and additions were made in preparation of a possible conversion into an injector for highly charged heavy ions as a second phase. This paper gives an overview of the experience gained in the passed 5 years and presents the status of the upgrade of the HCI.

  1. Longitudinal holes in debunched particle beams in storage rings, perpetuated by space-charge forces

    CERN Document Server

    Koscielniak, Shane Rupert; Lindroos, M

    2001-01-01

    Stationary, self-consistent, and localized longitudinal density perturbations on an unbunched charged-particle beam, which are solutions of the nonlinearized Vlasov-Poisson equation, have recently received some attention. In particular, we address the case that space charge is the dominant longitudinal impedance and the storage ring operates below transition energy so that the negative mass instability is not an explanation for persistent beam structure. Under the customary assumption of a bell-shaped steady-state distribution, about which the expansion is made, the usual wave theory of Keil and Schnell (1969) for perturbations on unbunched beams predicts that self-sustaining perturbations are possible only (below transition) if the impedance is inductive (or resistive) or if the bell shape is inverted. Space charge gives a capacitive impedance. Nevertheless, we report numerous experimental measurements made at the CERN Proton Synchrotron Booster that plainly show the longevity of holelike structures in coast...

  2. Non-Linear Beam Dynamics Studies of the Diamond Storage Ring

    CERN Document Server

    Bartolini, Riccardo; Belgroune, Mahdia; Henry Rowland, James; Jones, James; Martin, Ian; Singh, Beni

    2005-01-01

    The non-linear beam dynamics have been investigated for the non-zero dispersion lattice of the Diamond storage ring. Effects in realistic lattice configurations such as the introduction of coupling errors, beta beating, closed orbit correction, quadrupole fringe field and in-vacuum and helical insertion devices have been studied in the presence of realistic physical aperture limitations. Frequency map analysis together with 6D tracking allows identification of the limiting resonances as well as the loss locations and calculation of the influence of non-linear longitudinal motion on the Touschek lifetime. The sensitivity of the lattice to some of these effects leads to the identification of a better working point for the machine.

  3. An ultimate storage ring lattice with vertical emittance generated by damping wigglers

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaobiao [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)

    2015-01-06

    We discuss the approach of generating round beams for ultimate storage rings using vertical damping wigglers (with horizontal magnetic field). The vertical damping wigglers provide damping and excite vertical emittance. This eliminates the need to generate large linear coupling that is impractical with traditional off-axis injection. We use a PEP-X compatible lattice to demonstrate the approach. This lattice uses separate quadrupole and sextupole magnets with realistic gradient strengths. Intrabeam scattering effects are calculated. As a result, the horizontal and vertical emittances are 22.3 pm and 10.3 pm, respectively, for a 200 mA, 4.5 GeV beam, with a vertical damping wiggler of a total length of 90 m, a peak field of 1.5 T and a wiggler period of 100 mm.

  4. The trigger system for the external target experiment in the HIRFL cooling storage ring

    Science.gov (United States)

    Li, Min; Zhao, Lei; Liu, Jin-Xin; Lu, Yi-Ming; Liu, Shu-Bin; An, Qi

    2016-08-01

    A trigger system was designed for the external target experiment in the Cooling Storage Ring (CSR) of the Heavy Ion Research Facility in Lanzhou (HIRFL). Considering that different detectors are scattered over a large area, the trigger system is designed based on a master-slave structure and fiber-based serial data transmission technique. The trigger logic is organized in hierarchies, and flexible reconfiguration of the trigger function is achieved based on command register access or overall field-programmable gate array (FPGA) logic on-line reconfiguration controlled by remote computers. We also conducted tests to confirm the function of the trigger electronics, and the results indicate that this trigger system works well. Supported by the National Natural Science Foundation of China (11079003), the Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-YW-N27), and the CAS Center for Excellence in Particle Physics (CCEPP).

  5. Direct observation of spatio-temporal dynamics of short electron bunches in storage rings

    CERN Document Server

    Evain, C; Parquier, M Le; Szwaj, C; Tordeux, M -A; Manceron, L; Brubach, J -B; Roy, P; Bielawski, S

    2016-01-01

    In recent synchrotron radiation facilities, the use of short (picosecond) electron bunches is a powerful method for producing giant pulses of Terahertz Coherent Synchrotron Radiation (THz CSR). Here we report on the first direct observation of these pulse shapes with a few picoseconds resolution, and of their dynamics over a long time. We thus confirm in a very direct way the theories predicting an interplay between two physical processes. Below a critical bunch charge, we observe a train of identical THz pulses (a broadband Terahertz comb) stemming from the shortness of the electron bunches. Above this threshold, a large part of the emission is dominated by drifting structures, which appear through spontaneous self-organization. These challenging single-shot THz recordings are made possible by using a recently developed photonic time stretch detector with a high sensitivity. The experiment has been realized at the SOLEIL storage ring.

  6. Observation of microwave radiation using low-cost detectors at the ANKA storage ring*

    CERN Document Server

    Judin, V; Hofmann, A; Huttel, E; Kehrer, B; Klein, M; Marsching, S; Müller, A S; Nasse, M; Smale, N; Caspers, F; Peier, P

    2011-01-01

    Synchrotron light sources emit Coherent Synchrotron Radiation (CSR) for wavelengths longer than or equal to the bunch length. At most storage rings CSR cannot be observed, because the vacuum chamber cuts off radiation with long wavelengths. There are different approaches for shifting the CSR to shorter wavelengths that can propagate through the beam pipe, e.g.: the accelerator optics can be optimized for a low momentum compaction factor, thus reducing the bunch length. Alternatively, laser slicing can modulate substructures on long bunches [1]. Both techniques extend the CSR spectrum to shorter wavelengths, so that CSR is emitted at wavelengths below the waveguide shielding cut off. Usually fast detectors, like superconducting bolometer detector systems or Schottky barrier diodes, are used for observation of dynamic processes in accelerator physics. In this paper, we present observations of microwave radiation at ANKA using an alternative detector, a LNB (Low Noise Block) system. These devices are usually use...

  7. Interferometric measurement of the beam size in the compact storage ring

    CERN Document Server

    Yamamoto, Y; Mitsuhashi, T; Amano, D; Iwasaki, H

    2001-01-01

    The beam size in the compact superconducting storage ring AURORA at Ritsumeikan University was measured using the SR-interferometer. The radiation beam from the bending magnet was passed through the double-slit and an interferogram formed in the visible spectral region was recorded using a CCD camera. The spatial coherence of the beam was derived from the analysis of the intensity profile and its dependence on the spatial frequency has yielded the beam size of 10.5 mu m in the vertical direction. It is unexpectedly small, indicating a high accuracy in the design of magnetic field in the magnet. The beam size could be varied by applying an rf kick electric field and the dependence of the beam lifetime on the size has shown that it is primarily governed by the Tauschek effect.

  8. Coupling field maps of combined function bending magnets to linear optics for the SESAME storage ring

    CERN Document Server

    Milanese, A

    2013-01-01

    This note provides several analyses of the combined function bending magnets of the SESAME storage ring. The objective is to develop tools to couple the magnetic design to the linear optics specifications. Such tools can be used to carry out a 3D field optimization, at the design phase and following magnetic measurements, in particular in order to fine tune the end shims on the poles. The analyses take as input field maps on the midplane, which are then processed in different ways to obtain linear transfer matrices for the optics, in the horizontal and vertical planes. Some peculiarities of this kind of magnet are also highlighted, for example, the slight variation of gradient along the arc. For convenience, the relative codes and scripts are included in the appendix.

  9. Sub-picosecond coherent VUV source on the Elettra storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Spezzani, C. [Sincrotrone Trieste, Basovizza, Trieste (Italy)], E-mail: carlo.spezzani@elettra.trieste.it; Allaria, E.; Cautero, G. [Sincrotrone Trieste, Basovizza, Trieste (Italy); Coreno, M. [CNR-IMIP (Rome branch), c/o CNR-INFM TASC National Laboratory, Trieste (Italy); Curbis, F. [Sincrotrone Trieste, Basovizza, Trieste (Italy); University of Trieste (Italy); Danailov, M.B.; Demidovich, A.; Diviacco, B.; Karantzoulis, E.; Ivanov, R.K.; Pittana, P.; Romanzin, L.; Sergo, R.; Sigalotti, P.; Tileva, S.; Trovo, M. [Sincrotrone Trieste, Basovizza, Trieste (Italy); De Ninno, G. [Sincrotrone Trieste, Basovizza, Trieste (Italy); University of Nova Gorica (Slovenia)

    2008-11-11

    Taking advantage of the storage ring free electron laser beamline at Elettra, we have implemented an experimental setup for the generation of sub-picosecond (ps) coherent optical pulses in the VUV range. The setup is based on the frequency up-conversion of a high-power external signal (provided by a Ti:Sapphire laser) and makes use of a relativistic electron bunch as resonating medium. The produced VUV pulses have peak power in MW range, variable polarization, high shot to shot stability and control of the timing parameters at the ps level. In this paper, we present the first characterization of the temporal and spectral features of the emitted light. The radiation can be exploited for new experiments in the fields of dynamical phenomena, non-linear physics, magnetism and biology.

  10. Effects of vertical girder realignment in the Argonne APS storage ring.

    Energy Technology Data Exchange (ETDEWEB)

    Lessner, E.

    1999-04-14

    The effects of vertical girder misalignments on the vertical orbit of the Advanced Photon Source (APS) storage ring are studied. Partial sector-realignment is prioritized in terms of the closed-orbit distortions due to misalignments of the corresponding girders in the sectors. A virtual girder-displacement (VGD) method is developed that allows the effects of a girder realignment to be tested prior to physically moving the girder. The method can also be used to anticipate the corrector strengths needed to restore the beam orbit after a realignment. Simulation results are compared to experimental results and found to reproduce the latter quite closely. Predicted corrector strengths are also found to be close to the actual local corrector strengths after a proof-of-principle two-sector realignment was performed.

  11. Recent experience with inductive insert at the proton storage ring (PSR)

    Energy Technology Data Exchange (ETDEWEB)

    Ng, K.-Y (Kal Y.); Griffin, J. E. (James E.); Wildman, D.; Popovic, M. (Mihai); Browman, A. A. (Andrew A.); Fitzgerald, D. H. (Daniel H.); Macek, R. J. (Robert J.); Plum, M. A. (Michael A.); Spickermann, T. J. (Thomas J.)

    2001-01-01

    In a Fermilab-Los Alamos collaboration, inductances constructed of ferrite cores sufficient to cancel a large fraction of the space charge potential-well distortion were installed in the Los Alamos Proton Storage Ring (PSR) as one means of raising the threshold for the two-stream e-p instability. When operating at higher intensities and with sufficient inductance added for full space-charge compensation, an unacceptable longitudinal self-bunching, microwavelike, instability was encountered. Heating the cores to N 130 C proved to be an effective cure, and was found to be a means for tuning the inductance over a limited but useful range. The heated inductors were an essential ingredient in achieving a record accumulation of 9.7 pC/pulse. An engineered version of the inductors is now installed for routine operation of the PSR. A summary of the inductor characteristics, theory of operation, experimental results, and interpretation will be presented.

  12. PEP-X: An Ultimate Storage Ring Based on Fourth-Order Geometric Achromats

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yunhai; Bane, Karl; Hettel, Robert; Nosochkov, Yuri; Wang, Min-Huey; /SLAC

    2012-04-06

    We have designed an 'ultimate' storage ring for the PEP-X light source that achieves the diffraction limited emittances (at 1.5 {angstrom}) of 12 pm-rad in both horizontal and vertical planes with a 4.5-GeV beam. These emittances include the contribution of intrabeam scattering at a nominal current of 200 mA in 3300 bunches. This quality beam in conjunction with a conventional 4-m undulator in a straight section can generate synchrotron radiation having a spectral brightness above 10{sup 22} [photons/s/mm{sup 2}/mrad{sup 2}/0.1% BW] at a 10 keV photon energy. The high coherence at the diffraction limit makes PEP-X competitive with 4th generation light sources based on an energy recovery linac. In addition, the beam lifetime is several hours and the dynamic aperture is large enough to allow off-axis injection. The alignment and stability tolerances, though challenging, are achievable. A ring with all these properties is only possible because of several major advances in mitigating the effects of nonlinear resonances.

  13. 1000-TeV in the Center-Of-Mass: Introduction to High-Energy Storage Rings

    Energy Technology Data Exchange (ETDEWEB)

    Bjorken, J D

    1982-09-01

    The lecture discusses, in a pedagogic way, a hypothetical 500 TeV proton storage ring accelerator. It gives machine parameters, discusses linear optics and betatron motions, surveys questions of errors, tolerances and nonlinear resonances, and discusses some of the demands on the detection apparatus, especially the apparent inevitability of multiple interactions per bunch crossing. (GHT)

  14. Measurement of small-angle antiproton-proton and proton-proton elastic scattering at the CERN intersecting storage rings

    NARCIS (Netherlands)

    Amos, N.; Block, M.M.; Bobbink, G.J.; Botje, M.A.J.; Favart, D.; Leroy, C.; Linde, F.; Lipnik, P.; Matheys, J-P.; Miller, D.

    1985-01-01

    Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at . Using the optical theorem, total cross sections are obtained with an accuracy of about

  15. A strategy for a thorough beam stability and aperture analysis for a storage ring from design considerations

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, S.

    1988-07-01

    An outline of a possible approach to understanding and analyzing beam stability and related aperture as thoroughly as one can using tracking and all the other available analytic tools to date is presented in the context of designing any particular storage ring. 8 refs., 3 figs.

  16. First measurement of the Ru-96(p,gamma)Rh-97 cross section for the p process with a storage ring

    NARCIS (Netherlands)

    Mei, Bo; Aumann, Thomas; Bishop, Shawn; Blaum, Klaus; Boretzky, Konstanze; Bosch, Fritz; Brandau, Carsten; Braeuning, Harald; Davinson, Thomas; Dillmann, Iris; Dimopoulou, Christina; Ershova, Olga; Fueloep, Zsolt; Geissel, Hans; Glorius, Jan; Gyuerky, Gyoergy; Heil, Michael; Kaeppeler, Franz; Kelic-Heil, Aleksandra; Kozhuharov, Christophor; Langer, Christoph; Le Bleis, Tudi; Litvinov, Yuri; Lotay, Gavin; Marganiec, Justyna; Muenzenberg, Gottfried; Nolden, Fritz; Petridis, Nikolaos; Plag, Ralf; Popp, Ulrich; Rastrepina, Ganna; Reifarth, Rene; Riese, Bjoern; Rigollet, Catherine; Scheidenberger, Christoph; Simon, Haik; Sonnabend, Kerstin; Steck, Markus; Stoehlker, Thomas; Szuecs, Tamas; Suemmerer, Klaus; Weber, Guenter; Weick, Helmut; Winters, Danyal; Winters, Natalya; Woods, Philip; Zhong, Qiping

    2015-01-01

    This work presents a direct measurement of the Ru-96(p,gamma)Rh-97 cross section via a novel technique using a storage ring, which opens opportunities for reaction measurements on unstable nuclei. A proof-of-principle experiment was performed at the storage ring ESR at GSI in Darmstadt, where circul

  17. 2009 SCDNR Berkeley County Lidar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sanborn Map Company completed the original classification of the multiple return LiDAR of Berkeley County, South Carolina in 2009. In 2013, Dewberry was tasked with...

  18. Microscopic study on lasing characteristics of the UVSOR storage ring free electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Hama, H. [Institute for Molecular Science, Okazaki (Japan)]|[Graduate Univ. for Advanced Stuides, Okazaki (Japan); Yamazaki, J.; Kinoshita, T. [Institute for Molecular Science, Okazaki (Japan)] [and others

    1995-12-31

    Characteristics of storage ring free electron laser (SRFEL) at a short wavelength region (UV and visible) has been studied at the UVSOR facility, Institute for Molecular Science. We have measured the laser power evolution by using a biplanar photodiode, and the micro-macro temporal structure of both the laser and the electron bunch with a dualsweep streak camera. The saturated energy of the laser micropulse in the gain-switching (Q-switching) mode has been measured as a function of the ring current. We have not observed a limitation of the output power yet within the beam current can be stored. We have analyzed the saturated micropulse energy based on a model of gain reduction due to the bunch-heating. The bunch-heating process seems to be very complicate. We derived time dependent gain variations from the shape of macropulse and the bunch length. Those two gain variations are almost consistent with each other but slightly different in detail. The gain may be not only simply reduced by the energy spread but also affected by the phase space rotation due to synchrotron oscillation of the electron bunch. As reported in previous issue, the lasing macropulse consists of a couple of micropulses that are simultaneously evolved. From high resolution two-dimensional spectra taken by the dual-sweep streak camera, we noticed considerable internal substructures of the laser micropulse in both the time distribution and the spectral shape. There are a couple of peaks separated with almost same distance in a optical bunch. Such substructure does not seem to result from statistical fluctuations of laser seeds. Although the origin of the substructure of macropulse is not dear at the present, we are going to discuss about SRFEL properties.

  19. Electron beam properties and impedance characterization for storage rings used for free electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Dattoli, G.; Mezi, L.; Renieri, A. [ENEA, Divisione Fisica Applicata, Centro Ricerche Frascati, Frascati, RM (Italy); Migliorati, M. [Rome Univ. La Sapienza, Rome (Italy). Dipt. di Energetica; Couprie, M.E.; Garzella, D.; Nutarelli, D.; Thomas, C.; De Ninno, G. [Service de Photons, Atomes et Molecules DSM/DRECAM, Gif Sur Yvette (France); Walker, R. [Sincrotrone, Basorizza, TS (Italy)

    2000-07-01

    Good electron beam qualities and stability are the crucial features of Storage Rings dedicated to synchrotron radiation sources or to Free Electron Laser. Most of these characteristics depends on the coupling of the e-beam with the machine environment, which can be in turn modelled in terms of a characteristic impedance, whose absolute value and structure can be used to specify both the stability (longitudinal and transverse) of the beam and its qualities (energy spread, bunch length, peak current ...). In this paper are considered two specific examples of Storage Rings used for FEL operation and analyze their performances by means of semi analytical and numerical methods. The analysis is aimed at clarifying the dependence of beam energy spread and bunch length on beam current and at providing a set of parameters useful for the optimization of Free Electron Laser or synchrotron radiation sources. [Italian] La qualita' di fascio di un anello di accumulazione e la sua stabilita' sono le caratteristiche cruciali di un anello di accumulazione dedicato a sorgenti di Luce di Sincrotrone o al Laser ad Elettroni Liberi. La gran parte di tali caratteristiche dipende dall'accoppiamento del fascio di elettroni con la macchina stessa, tale accoppiamento puo' essere descritto in termini di una impedenza caratteristica, il cui valore assoluto e struttura possono essere utilizzati per specificarne sia la stabilita' del fascio (longitudinale e trasversale) e le sue qualita' (dispersione di energia, lunghezza del pacchetto, corrente di picco ...). In questo articolo si considerano due esempi specifici di anelli di accumulazione utilizzati per l'operazione Laser ed Elettroni Liberi e si analizzano le loro caratteristiche per mezzo di metodi semianalitici e numerici. L'analisi e' essenzialmente dedicata a chiarire la dipendenza della dispersione di energia e della lunghezza del pacchetto dalla corrente media e a fornire un insieme di

  20. Resonant pickups for non-destructive single-particle detection in heavy-ion storage rings and first experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Sanjari, Mohammad Shahab

    2013-04-26

    Nuclear astrophysics studies on highly charged radionuclides benefit from accelerator facilities with storage rings, where exotic nuclides produced with small yields can be efficiently investigated. Currently there are two accelerator facilities capable of storing highly charged heavy ions, GSI in Darmstadt and IMP in Lanzhou. Non-destructive detection methods are often used for in-flight measurements based on frequency analysis. The sensitivity of such detection systems are of primary importance specially when number of stored ions is small. Furthermore, since the exotic nuclides of interest are as a rule short-lived, the detectors must be fast. One common form of such detectors are parallel plate SCHOTTKY monitors, on which particles induce a mirror charge at each passage. This method has been successfully used at ESR experimental storage ring of GSI since 1991. In this work we describe a new resonant SCHOTTKY pickup operating as a high sensitive cavity current monitor which was mounted and commissioned in the ESR early 2010. It was successfully used in several storage ring experiments. A very similar pickup was mounted in CSRe at IMP Lanzhou in 2011. First in-ring tests have been performed and new experimental results are pending. The spectral analysis of acquired signals by the new detector has enabled a broad range of new physics experiments. The theory of operation and first experimental results and future perspectives are presented in this thesis.

  1. 76 FR 37650 - Safety Zone; 4th of July Festival Berkeley Marina Fireworks Display Berkeley, CA

    Science.gov (United States)

    2011-06-28

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; 4th of July Festival Berkeley Marina Fireworks Display Berkeley, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast... Berkeley Pier, Berkeley, CA in support of the 4th of July Festival Berkeley Marina Fireworks...

  2. The trapped ion-electron instability in an electron storage ring with a gap in the bunch train

    Science.gov (United States)

    Bosch, R. A.

    2000-08-01

    The trapped ion-electron instability in an electron storage ring is studied for a broad distribution of natural ion oscillation frequencies, termed ion bounce frequencies. A gap in the train of electron bunches may be used to create bands of unstable ion bounce frequencies, so that an ion species is ejected from regions of the ring where its horizontal or vertical bounce frequency is unstable. Expressions are obtained for the reduction in the incoherent tune shifts and trapped ion-electron instability growth rates resulting from the gap.

  3. The trapped ion-electron instability in an electron storage ring with a gap in the bunch train

    Energy Technology Data Exchange (ETDEWEB)

    Bosch, R.A. E-mail: bosch@src.wisc.edu

    2000-08-11

    The trapped ion-electron instability in an electron storage ring is studied for a broad distribution of natural ion oscillation frequencies, termed ion bounce frequencies. A gap in the train of electron bunches may be used to create bands of unstable ion bounce frequencies, so that an ion species is ejected from regions of the ring where its horizontal or vertical bounce frequency is unstable. Expressions are obtained for the reduction in the incoherent tune shifts and trapped ion-electron instability growth rates resulting from the gap.

  4. Dynamic Aperture and Tolerances for PEP-X Ultimate Storage Ring Design

    Energy Technology Data Exchange (ETDEWEB)

    Borland, M.; /Argonne; Cai, Y.; Nosochkov, Y.; Wang, M.-H.; /SLAC; Hettel, R.O.; /SLAC

    2011-12-13

    A lattice for the PEP-X ultimate storage ring light source, having 11 pm-rad natural emittance at a beam energy of 4.5 GeV at zero current, using 90 m of damping wiggler and fitting into the existing 2.2-km PEP-II tunnel, has been recently designed. Such a low emittance lattice requires very strong sextupoles for chromaticity correction, which in turn introduce strong non-linear field effects that limit the beam dynamic aperture. In order to maximize the dynamic aperture we choose the cell phases to cancel the third and fourth order geometric resonances in each 8-cell arc. Four families of chromatic sextupoles and six families of geometric (or harmonic) sextupoles are added to correct the chromatic and amplitude-dependent tunes. To find the best settings of the ten sextupole families, we use a Multi-Objective Genetic Optimizer employing elegant to optimize the beam lifetime and dynamic aperture simultaneously. Then we evaluate dynamic aperture reduction caused by magnetic field multipole errors, magnet fabrication errors and misalignments. A sufficient dynamic aperture is obtained for injection, as well as workable beam lifetime.

  5. XAS at the materials science X-ray beamline BL8 at the DELTA storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Frahm, R; Wagner, R; Luetzenkirchen-Hecht, D [Fachbereich C - Physik, Bergische Universitaet Wuppertal, Gaussstrasse 20, 42097 Wuppertal (Germany); Herdt, A, E-mail: frahm@uni-wuppertal.d [Fachbereich Physik/DELTA, Technische Universitaet Dortmund, Maria-Goeppert-Mayer-Strasse 2, 44221 Dortmund (Germany)

    2009-11-15

    The hard X-ray beamline BL 8 at the 1.5 GeV electron storage ring DELTA is described, and experimental data of different fields of research are presented. Making use of the intense X-ray beam emitted by a superconducting wiggler, the beamline is dedicated to X-ray absorption experiments. Three different monochromator crystal pairs are permanently available for experiments in the spectral range from about 1 keV to ca. 25 keV photon energy. Results of reference materials show that high quality EXAFS data can be obtained using Si(111) and Si(311) monochromators. First measurements in the energy range between 1.2 and 5 keV have been accomplished using YB{sub 66}(400) monochromator crystals. The experimental hutch accommodates a unique 6-axis diffractometer which is well suited for all kinds of diffraction and absorption experiments, including the grazing incidence geometry. The diffractometer can carry heavy loads related to non-ambient sample environments such as e.g. ultrahigh vacuum sample stages or cryostats. Here we present typical results obtained at BL8 in different areas of materials science including investigations of dilute alloys by fluorescence mode EXAFS and the study of the structural changes associated with temperature induced spin transitions of metallo-supramolecular polyelectrolyte-amphiphile-complexes.

  6. Design and erection of the storage ring ANKA; Entwurf und Aufbau des Speicherringes ANKA

    Energy Technology Data Exchange (ETDEWEB)

    Einfeld, D. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). FGS

    2000-07-01

    The storage ring ANKA has been designed to meet the requirements of its main users: the LIGA technique and the analytical applications. According to this ANKA has to provide photons with an energy of up to 30 keV with a medium emittance (50 to 90 nm . rad), but with a high photon flux which corresponds to a stored beam of 400 mA. The nominal energy of ANKA is 2.5 GeV with a magnetic flux in the bendings of 1,5 T. To reach the emittance a classical DBA-structure over an angle of 45 degree has been used. ANKA has a circumference of 110.4 m with 4 long straight sections (5.6 m long) for the accomodation of future insertion devices and 4 short straight section (2.2 m) for the r. f. as well as the injection system. The injector is a 500 MeV booster synchrotron with a 53 MeV racetrack microtron as a pre-injector. (orig.)

  7. HISTRAP: Proposal for a Heavy Ion Storage Ring for Atomic Physics

    Energy Technology Data Exchange (ETDEWEB)

    1988-11-01

    This paper presents an overview of the physics capabilities of HISTRAP together with a brief description of the facility and a sampling of the beams which will be available for experimentation, and surveys some of the lines of investigation in the physics of multicharged ions, molecular ion spectroscopy, condensed beams, and nuclear physics that will become possible with the advent of HISTRAP. Details of the accelerator design are discussed, including computer studies of beam tracking in the HISTRAP lattice, a discussion of the HHIRF tandem and ECR/RFQ injectors, and a description of the electron beam cooling system. In the past three years, HISTRAP has received substantial support from Oak Ridge National Laboratory management and staff. The project has used discretionary funds to develop hardware prototypes and carry out design studies. Construction has been completed on a vacuum test stand which models 1/16 of the storage ring and has attained a pressure of 4 x 10/sup -12/ Torr; a prototype rf cavity capable of accelerating beams up to 90 MeV/nucleon and decelerating to 20 keV/nucleon; and a prototype dipole magnet, one of the eight required for the HISTRAP lattice. This paper also contains a summary of the work on electron cooling carried out by one of our staff members at CERN. Building structures and services are described. Details of cost and schedule are also discussed. 77 refs.

  8. A multi-length bunch design for electron storage rings with odd buckets

    Institute of Scientific and Technical Information of China (English)

    ZHU Liang-Jing; LI Wei-Min; WANG Lin; XIANG Dao; HUANG Xiao-Biao

    2015-01-01

    A scheme with two superconducting RF cavities is designed to upgrade electron storage rings with odd buckets to multi-length bunches.In this paper,the Hefei Light Source Ⅱ (HLS Ⅱ) is given as an example for odd buckets.As it is designed for 45 buckets,which is a multiple of 3,simultaneous generation of three different lengths of bunches is proposed with the presently applied user optics.The final result,without low-α optics,is to fill HLS Ⅱ with long bunches of length 50 ps,medium bunches of 23 ps and short bunches of 6 ps.Every third bucket can be filled with short bunches,of which the current limit is up to 6.6 mA,more than 60 times the limit for low-α mode.Moreover,particle tracking simulations to examine the beam dynamics,performed by ELEGANT,and calculations of the beam instabilities are presented in this paper.

  9. Measurement of bunch length in Indus-1 storage ring using fast photodiode

    Science.gov (United States)

    Garg, Akash Deep; Nathwani, R. K.; Holikatti, A. C.; Kumar Karnewar, Akhilesh; Tyagi, Y.; Yadav, S.; Puntambekar, T. A.; Navathe, C. P.

    2012-11-01

    The length of electron bunches in a storage ring is an important parameter for both synchrotron radiation users and accelerator physicists. Several methods are used for measurements of bunch length using electronic and optical instruments. We have measured temporal profile of synchrotron radiation emitted from dipole magnet of Indus-1 by using fast photodiode. Bunch length is calculated by assuming gaussian profile for the particles inside bunch. The results show that bunch length is increasing with the decrease of gap voltage of RF cavity. These measurements were carried out at low beam current; at high voltage results are in close agreement with theory and the values estimated using ZAP code. In the second experiment, the results show that bunch length increases with the increase of beam current inside the bunch, and above threshold current, it follows Chao-Gareyte scaling law. The longitudinal broadband impedance for Indus-1 SRS was estimated using Keil-Schnell criterion and results were compared with theoretical estimated values using ZAP code.

  10. Investigation on the fabrication of the 3rd harmonic superconducting cavity for the SSRF storage ring

    Institute of Scientific and Technical Information of China (English)

    MA Zhen-Yu; MA Guang-Ming; YU Hai-Bo; MAO Dong-Qing; FENG Zi-Qiang; HOU Hong-Tao; LIU Jian-Fei

    2009-01-01

    A third harmonic superconducting niobium cavity has been proposed for installation in the Shang-hai Synchrotron Radiation Facility (SSRF) storage ring to improve the Touschek lifetime. In order to investigate the feasibility of the superconducting cavity fabrication indigenously and the possibility to master the fabrica-tion techniques, cavities were fabricated from copper and niobium sheets by deep drawing and electron-beam welding, and a series of measurements, such as resonant frequency, shape dimensions and wall thickness, were carried out during this process. After analysis of various problems existing in the fabrication process, tech-nique improvements were proposed, and finally the precise shape as designed and resonant frequency within 1.2 MHz were achieved for the new completed cavities. In addition, full annealing was finally proved to be a good cure for niobium sheets' tearing up during deep drawing. By fabricating niobium cavities successfully, some problems to the next step were cleared. This paper introduces the process of cavity fabrication and its technique improvements towards forming, and the initial vertical test result of niobium cavity is also presented.

  11. New energy ramping control system in the Pohang Light Source Storage Ring

    CERN Document Server

    Kim, E S; Seo, J H; Nam, S H

    2003-01-01

    A new energy ramping control system is developed to increase electron beam energy from 2.0 GeV to 2.5 GeV in the Pohang Light Source storage ring. The control system shows faster energy ramping and more stable beam characteristics than the previous energy ramping control system that consists of an operator interface workstation, subsystem control computer and machine interface units. The previous system controls current settings of the magnet power supplies in multiple steps with different energy increment rate during the energy ramping. In order to improve synchronization of the magnet power supply systems and beam stabilities during the energy ramping, we developed the energy ramping controller hardware that is controlled using a network of optical fibers. Thus, the new ramping system is able to control more synchronously the magnet power supplies with a constant energy increment rate during the energy ramping. With this reliable synchronization, it is also possible to perform the energy de-ramping step fro...

  12. The search for electric dipole moments of light ions in storage rings

    Science.gov (United States)

    Rathmann, Frank; Saleev, Artem; Nikolaev, N. N.; Jedi; srEdm Collaborations

    2013-07-01

    The Standard Model (SM) of Particle Physics is not capable of accounting for the apparent matter-antimatter asymmetry of our universe. Physics beyond the SM is required and is searched for by (i) employing highest energies (e.g., at LHC), and (ii) striving for ultimate precision and sensitivity (e.g., in the search for electric dipole moments (EDMs)). Permanent EDMs of particles violate both time reversal (T) and parity (P) invariance, and are via the CPT-theorem also CP-violating. Finding an EDM would be a strong indication for physics beyond the SM, and reducing upper limits further provides crucial tests for any corresponding theoretical model, e.g., SUSY. Direct searches for proton and deuteron EDMs bear the potential to reach sensitivities beyond 10-29 e·cm. For an all-electric proton storage ring, this goal is pursued by the US-based srEDM collaboration [1], while the newly founded Jülich-based JEDI collaboration [2] is pursuing an approach using a combined electric-magnetic lattice, which shall provide access to the EDMs of protons, deuterons, and 3He ions in the same machine. In addition, JEDI has recently proposed making a direct measurement of the proton and/or deuteron EDM at COSY using resonant techniques involving Wien filters.

  13. Search for electric dipole moments of light ions in storage rings

    Science.gov (United States)

    Rathmann, F.; Saleev, A.; Nikolaev, N. N.

    2014-01-01

    The Standard Model (SM) of Particle Physics is not capable to account for the apparent matterantimatter asymmetry of our Universe. Physics beyond the SM is required and is searched for by (i) employing highest energies (e.g., at LHC), and (ii) striving for ultimate precision and sensitivity (e.g., in the search for electric dipole moments (EDMs)). Permanent EDMs of particles violate both time reversal ( T) and parity ( P) invariance, and are via the CPT-theorem also CP-violating. Finding an EDM would be a strong indication for physics beyond the SM, and pushing upper limits further provides crucial tests for any corresponding theoretical model, e.g., SUSY. Direct searches of proton and deuteron EDMs bear the potential to reach sensitivities beyond 10-29 e cm. For an all-electric proton storage ring, this goal is pursued by the US-based srEDM collaboration [2], while the newly found Julich-based JEDI collaboration [1] is pursuing an approach using a combined electric-magnetic lattice which shall provide access to the EDMs of protons, deuterons, and 3He ions in the same machine. In addition, JEDI has recently proposed to perform a direct measurement of the proton and/or deuteron EDM at COSY using resonant techniques involving Wien filters.

  14. Towards an RF-Wien-filter for EDM experiments in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Mey, Sebastian; Gebel, Ralf [Forschungszentrum Juelich GmbH, Juelich (Germany); Collaboration: JEDI-Collaboration

    2015-07-01

    The JEDI Collaboration (Juelich Electric Dipole Moment (EDM) Investigations) is developing tools for the measurement of permanent EDMs of charged, light hadrons in storage rings. While the standard model prediction for the EDM gives unobservably small magnitudes, a non-vanishing EDM can lead to a tiny build-up of vertical polarization in a beforehand horizontally polarized beam. This requires a spin tune modulation by an RF Wien-Filter *. In the course of 2014, a prototype RF ExB-Dipole has been successfully commissioned and tested. To determine the characteristics of the device, the force of a radial magnetic field is canceled out by a vertical electric one to achieve a net Lorentz-Force compensation. In this configuration, it directly rotates the particles' polarization vector. We were able to verify that the device can be used to continuously flip the vertical polarization of a 970 MeV/c deuteron beam without exciting any coherent beam oscillations. For a first EDM Experiment, the RF ExB-Dipole in Wien-Filter mode is going to be rotated by 90 {sup circle} around the beam axis and will be used for systematic investigations of sources for false EDM signals.

  15. Spin tune investigations for the storage ring EDM experiment at COSY

    Energy Technology Data Exchange (ETDEWEB)

    Chekmenev, Stanislav [III. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); Collaboration: JEDI-Collaboration

    2015-07-01

    An experimental method which is aimed to find a permanent electric dipole moment (EDM) of a charged particle was proposed by JEDI (Juelich Electric Dipole moment Investigations) collaboration [1]. EDMs can be observed by their small influence on spin motion. The only possible way to perform a direct measurement is to use a storage ring. For this purpose, it was decided to carry out the first precursor experiment at the Cooler Synchrotron (COSY). Since the EDM of a particle violates CP invariance it is expected to be tiny, treatment of all various sources of systematic errors should be done with a great level of precision. A recent achievement of the JEDI collaboration is the determination of the spin tune with a precision of 10{sup -10} in a single accelerator cycle. In parallel with that achievement a new spin tracking code was developed. It is planned to use the spin tune measurement to benchmark the simulation code. In the last data taking period, spin motion changes were generated by steerers and solenoids. Comparison of simulation results with data collected will be discussed.

  16. Measurement of permanent electric dipole moments of charged hadrons in storage rings

    Science.gov (United States)

    Pretz, Jörg

    2013-03-01

    Permanent Electric Dipole Moments (EDMs) of elementary particles violate two fundamental symmetries: time reversal invariance ({T}) and parity ({P}). Assuming the {CPT} theorem this implies {CP} violation. The {CP} violation of the Standard Model is orders of magnitude too small to be observed experimentally in EDMs in the foreseeable future. It is also way too small to explain the asymmetry in abundance of matter and anti-matter in our universe. Hence, other mechanisms of {CP} violation outside the realm of the Standard Model are searched for and could result in measurable EDMs. Up to now most of the EDM measurements were done with neutral particles. With new techniques it is now possible to perform dedicated EDM experiments with charged hadrons at storage rings where polarized particles are exposed to an electric field. If an EDM exists the spin vector will experience a torque resulting in change of the original spin direction which can be determined with the help of a polarimeter. Although the principle of the measurement is simple, the smallness of the expected effect makes this a challenging experiment requiring new developments in various experimental areas. Complementary efforts to measure EDMs of proton, deuteron and light nuclei are pursued at Brookhaven National Laboratory and at Forschungszentrum Jülich with an ultimate goal to reach a sensitivity of 10 - 29 e·cm.

  17. Characterization of electron clouds in the Cornell Electron Storage Ring Test Accelerator using TE-wave transmission

    Energy Technology Data Exchange (ETDEWEB)

    De Santis, S.; Byrd, J. M.; Billing, M.; Palmer, M.; Sikora, J.; Carlson, B.

    2010-01-02

    A relatively new technique for measuring the electron cloud density in storage rings has been developed and successfully demonstrated [S. De Santis, J.M. Byrd, F. Caspers, A. Krasnykh, T. Kroyer, M.T.F. Pivi, and K.G. Sonnad, Phys. Rev. Lett. 100, 094801 (2008).]. We present the experimental results of a systematic application of this technique at the Cornell Electron Storage Ring Test Accelerator. The technique is based on the phase modulation of the TE mode transmitted in a synchrotron beam pipe caused by the periodic variation of the density of electron plasma. Because of the relatively simple hardware requirements, this method has become increasingly popular and has been since successfully implemented in several machines. While the principles of this technique are straightforward, quantitative derivation of the electron cloud density from the measurement requires consideration of several effects, which we address in detail.

  18. Photo excitation and laser detachment of C60 − anions in a storage ring

    DEFF Research Database (Denmark)

    Støchkel, Kristian; Andersen, Jens Ulrik

    2013-01-01

    (REMPED) has been repeated both at room temperature and with the trap cooled to liquid nitrogen temperature. However, wavelength dependence of the overlap of the strongly focused laser beam with the ion beam introduces distortions of the absorption spectrum. We have therefore applied a new method...... level, is much weaker in the new measurements and could be an H g vibrational sideband. Also earlier studies of direct laser detachment from C60 − in the storage ring ASTRID have been revisited, with ions cooled by liquid nitrogen in the ion trap. We confirm the previous measurement with a determination......We have studied the photo physics of C60 − anions in the electrostatic storage ring ELISA with ions produced in a plasma source and cooled and bunched in a He filled ion trap. A previous study using delayed electron detachment as a signal of resonance-enhanced multiphoton electron detachment...

  19. Relativistic, QED and nuclear effects in highly charged ions revealed by resonant electron-ion recombination in storage rings

    OpenAIRE

    Schippers, Stefan

    2008-01-01

    Dielectronic recombination (DR) of few-electron ions has evolved into a sensitive spectroscopic tool for highly charged ions. This is due to technological advances in electron-beam preparation and ion-beam cooling techniques at heavy-ion storage rings. Recent experiments prove unambiguously that DR collision spectroscopy has become sensitive to 2nd order QED and to nuclear effects. This review discusses the most recent developments in high-resolution spectroscopy of low-energy DR resonances, ...

  20. X-ray nanoprobes and diffraction-limited storage rings: opportunities and challenges of fluorescence tomography of biological specimens

    Energy Technology Data Exchange (ETDEWEB)

    Jonge, Martin D. de, E-mail: martin.dejonge@synchrotron.org.au [Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia); Ryan, Christopher G. [CSIRO Earth Science and Research Engineering, Clayton, Victoria 3168 (Australia); Jacobsen, Chris J. [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Department of Physics, Chemistry of Life Processes Institute, Northwestern University, 2170 Campus Drive, Evanston, IL 60208 (United States); Chemistry of Life Processes Institute, Northwestern University, 2170 Campus Drive, Evanston, IL 60208 (United States)

    2014-08-27

    Nanoscale X-ray scanning microscopes, or X-ray nanoprobes, will benefit greatly from diffraction-limited storage rings. Here the requirements for nanoscale fluorescence tomography are explored to gain insight into the scientific opportunities and technical challenges that such sources offer. X-ray nanoprobes require coherent illumination to achieve optic-limited resolution, and so will benefit directly from diffraction-limited storage rings. Here, the example of high-resolution X-ray fluorescence tomography is focused on as one of the most voracious demanders of coherent photons, since the detected signal is only a small fraction of the incident flux. Alternative schemes are considered for beam delivery, sample scanning and detectors. One must consider as well the steps before and after the X-ray experiment: sample preparation and examination conditions, and analysis complexity due to minimum dose requirements and self-absorption. By understanding the requirements and opportunities for nanoscale fluorescence tomography, one gains insight into the R&D challenges in optics and instrumentation needed to fully exploit the source advances that diffraction-limited storage rings offer.

  1. Ion optics and beam dynamics optimization at the HESR storage ring for the SPARC experiments with highly charged heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Kovalenko, Oleksandr

    2015-06-24

    The High-Energy Storage Ring (HESR) is a part of an upcoming International Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt. A key part of a scientific program, along with antiproton physics, will be physics with highly-charged heavy ions. Phase-space cooled beams together with fixed internal target will provide an excellent environment for storage ring experiments at the HESR for the SPARC collaboration. Until recently, however, the existing ion optical lattice for the HESR was designed only for the experiments with antiproton beams. The thesis presents a new ion optical mode developed specifically for the operation of the HESR with highly charged heavy ions. The presence of the errors, such as beam momentum spread, magnetic field impurities or magnets misalignments, leads to disruption of beam dynamics: exciting of resonant motion and loss of beam stability. Within the paper, these effects are investigated with the help of numerical codes for particle accelerator design and simulation MAD-X and MIRKO. A number of correction techniques are applied to minimize the nonlinear impact on the beam dynamics and improve the experimental conditions. The application of the analytical and numerical tools is demonstrated in the experiment with uranium U{sup 90+} beam at the existing storage ring ESR, GSI.

  2. Simulation of crystalline beams in storage rings using molecular dynamics technique

    Science.gov (United States)

    Meshkov, I.; Katayama, T.; Sidorin, A.; Smirnov, A.; Syresin, E.; Trubnikov, G.; Tsutsui, H.

    2006-03-01

    Achieving very low temperatures in the beam rest frame can present new possibilities in accelerator physics. Increasing luminosity in the collider and in experiments with targets is a very important asset for investigating rare radioactive isotopes. The ordered state of circulating ion beams was observed at several storage rings: NAP-M [Budker, et al., in: Proceedings of the 4th All-Union Conference on Charged-Particle Accelerators [in Russian], vol. 2, Nauka, Moscow, 1975, p. 309; Budker et al., Part. Accel. 7 (1976) 197; Budker et al., At. Energ. 40 (1976) 49. E. Dementev, N. Dykansky, A. Medvedko et al., Prep. CERN/PS/AA 79-41, Geneva, 1979] (Novosibirsk), ESR [M. Steck et al., Phys. Rev. Lett. 77 (1996) 3803] and SIS [Hasse and Steck, Ordered ion beams, in: Proceeding of EPAC '2000] (Darmstadt), CRYRING [Danared et al., Observation of ordered ion beams in CRYRING, in: Proceeding of PAC '2001] (Stockholm) and PALLAS [Schramm et al., in: J.L. Duggan (Eds.), Proceedings of the Conference on Appl. of Acc. in Research and Industry AIP Conference Proceedings, p. 576 (to be published)] (Munich). In this report, the simulation of 1D crystalline beams with BETACOOL code is presented. The sudden reduction of momentum spread in the ESR experiment is described with this code. Simulation shows good agreement with experimental results and also with the intrabeam scattering (IBS) theory [Martini, Intrabeam scattering in the ACOOL-AA machines, CERN PS/84-9 AA, Geneva, 1984]. The code was used to calculate characteristics of the ordered state of ion beams for the TARN-II [Katayama, TARN II project, in: Proceedings of the IUCF workshop on nuclear physics with stored cooled beams, Spencer, IN, USA, 1984].

  3. Overlap knock-out effects in the CERN intersecting storage rings (ISR)

    CERN Document Server

    Gourber, J P; Myers, S

    1977-01-01

    Overlap knock-out arises from an overlap between frequencies present in a bunched beam and the betatron frequencies in a stack. The 'single ring' effect in the interaction of a bunched beam with a stack in the same ring. Here the coupling forces are fairly linear and are transmitted by machine elements. The 'two-ring' effect is the interaction of a bunched beam with a stack in the other ring. Here the coupling forces are nonlinear since they are produced by the beam-beam interaction. A brief outline of the general theory of these effects is given. The single ring and two-ring dipole effects have been observed and shown to cause a large increase in the transverse size of the stacked beam. (4 refs).

  4. High-Precision Storage Ring for g-2 of the Muon and Possible Applications in Particle and Heavy Ion Physics

    CERN Document Server

    Jungmann, Klaus

    1998-01-01

    A new superferric magnetic storage ring with highly homogeneous field at 1.45 T and weak electrostatic focussing is described which has been set up at the Brookhaven National Laboratory (BNL), USA, for a precision measurement of the magnetic anomaly of the muon. The toroidal storage volume has a radius of 7 m and a diameter of 9 cm. Precision magnetic field determination based on pulsed NMR on protons in H$_2$O yields the field to better than 0.1 ppm everywhere within the storage region. Follow on experiments using the setup have been already suggested to search for a finite mass of the muon neutrino and to search for an electric dipole moment of the muon with significantly increased accuracy. The high homogeneity of the field suggests the usage of such devices as a mass spectrometer for heavier particles as well.

  5. Molecular Foundry, Berkeley, California (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Carlisle, N.

    2008-03-01

    This case study provides information on the Molecular Foundry, which incorporates Labs21 principles in its design and construction. The design includes many of the strategies researched at Lawrence Berkeley Laboratory for energy efficient cleanroom and data centers. The result is an energy efficient high-performing sustainable laboratory.

  6. Five-membered rings as diazo components in optical data storage devices: An ab initio investigation of the lowest singlet excitation energies

    DEFF Research Database (Denmark)

    Åstrand, P.-O.; Sommer-Larsen, P.; Hvilsted, Søren;

    2000-01-01

    been investigated as diazo components for a potential use in optical das storage materials. It is found that the diazo compounds with two heterocyclic five-membered rings have pi --> pi* excitation energies corresponding to laser wavelengths in the region 450-500 nm whereas one five-membered ring...

  7. 78 FR 29022 - Safety Zone; Fourth of July Fireworks, Berkeley Marina, Berkeley, CA

    Science.gov (United States)

    2013-05-17

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fourth of July Fireworks, Berkeley Marina, Berkeley, CA... enforce the safety zone for the Berkeley Marina Fourth of July Fireworks display in the Captain of the... Berkeley Pier in approximate position 37 51'40'' N, 122 19'19'' W (NAD 83) from 9:30 p.m. until 10:15...

  8. CsI-Silicon Particle detector for Heavy ions Orbiting in Storage rings (CsISiPHOS)

    Science.gov (United States)

    Najafi, M. A.; Dillmann, I.; Bosch, F.; Faestermann, T.; Gao, B.; Gernhäuser, R.; Kozhuharov, C.; Litvinov, S. A.; Litvinov, Yu. A.; Maier, L.; Nolden, F.; Popp, U.; Sanjari, M. S.; Spillmann, U.; Steck, M.; Stöhlker, T.; Weick, H.

    2016-11-01

    A heavy-ion detector was developed for decay studies in the Experimental Storage Ring (ESR) at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany. This detector serves as a prototype for the in-pocket particle detectors for future experiments with the Collector Ring (CR) at FAIR (Facility for Antiproton and Ion Research). The detector includes a stack of six silicon pad sensors, a double-sided silicon strip detector (DSSD), and a CsI(Tl) scintillation detector. It was used successfully in a recent experiment for the detection of the β+-decay of highly charged 142Pm60+ ions. Based on the ΔE / E technique for particle identification and an energy resolution of 0.9% for ΔE and 0.5% for E (Full Width at Half Maximum (FWHM)), the detector is well-suited to distinguish neighbouring isobars in the region of interest.

  9. Analysis of the wake field effects in the PEP-II storage rings with extremely high currents

    Energy Technology Data Exchange (ETDEWEB)

    Novokhatski, A., E-mail: novo@slac.stanford.edu; Seeman, J.; Sullivan, M.

    2014-01-21

    We present the history and analysis of different wake field effects throughout the operational life of the PEP-II SLAC B-factory. Although the impedance of the high and low energy rings is small, the intense high-current beams generated a lot of power. The effects from these wake fields are: heating and damage of vacuum beam chamber elements like RF seals, vacuum valves, shielded bellows, BPM buttons and ceramic tiles; vacuum spikes, vacuum instabilities and high detector background; and beam longitudinal and transverse instabilities. We also discuss the methods used to eliminate these effects. Results of this analysis and the PEP-II experience may be very useful in the design of new storage rings and light sources.

  10. Analysis of the wake field effects in the PEP-II storage rings with extremely high currents

    Science.gov (United States)

    Novokhatski, A.; Seeman, J.; Sullivan, M.

    2014-01-01

    We present the history and analysis of different wake field effects throughout the operational life of the PEP-II SLAC B-factory. Although the impedance of the high and low energy rings is small, the intense high-current beams generated a lot of power. The effects from these wake fields are: heating and damage of vacuum beam chamber elements like RF seals, vacuum valves, shielded bellows, BPM buttons and ceramic tiles; vacuum spikes, vacuum instabilities and high detector background; and beam longitudinal and transverse instabilities. We also discuss the methods used to eliminate these effects. Results of this analysis and the PEP-II experience may be very useful in the design of new storage rings and light sources.

  11. Capture, acceleration and bunching rf systems for the MEIC booster and storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shaoheng [Jefferson Lab, Newport News, VA; Guo, Jiquan [Jefferson Lab, Newport News, VA; Lin, Fanglei [Jefferson Lab, Newport News, VA; Morozov, Vasiliy [Jefferson Lab, Newport News, VA; Rimmer, Robert A. [Jefferson Lab, Newport News, VA; Wang, Haipeng [Jefferson Lab, Newport News, VA; Zhang, Yuhong [Jefferson Lab, Newport News, VA

    2015-09-01

    The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. The electron collider ring accepts electrons from CEBAF at energies from 3 to 12 GeV. Protons and ions are delivered to a booster and captured in a long bunch before being ramped and transferred to the ion collider ring. The ion collider ring accelerates a small number of long ion bunches to colliding energy before they are re-bunched into a high frequency train of very short bunches for colliding. Two sets of low frequency RF systems are needed for the long ion bunch energy ramping in the booster and ion collider ring. Another two sets of high frequency RF cavities are needed for re-bunching in the ion collider ring and compensating synchrotron radiation energy loss in the electron collider ring. The requirements from energy ramping, ion beam bunching, electron beam energy compensation, collective effects, beam loading and feedback capability, RF power capability, etc. are presented. The preliminary designs of these RF systems are presented. Concepts for the baseline cavity and RF station configurations are described, as well as some options that may allow more flexible injection and acceleration schemes.

  12. The Pulsed Power Converter and Septum Magnet System for Injection into the Electron Storage Ring at ESRF

    CERN Document Server

    Perrine, J P; Völker, F V

    1996-01-01

    At ESRF, the European Synchrotron Radiation Facility in Grenoble, electrons are accelerated, via a 200 MeV Linac and a 6 GeV synchrotron booster, and injected into the storage ring at 10 Hz rate. Two thin septum blade magnets and an eddy current sheet type septum magnet provide the final deflection of the injected beam. The operational requirements of the e- injection scheme and the resulting demanding hardware specifications are recalled. The pulsed septum magnets are briefly described. The design, circuit layout and construction of the power converters are related with emphasis on innovative aspects of general interest. Results of tests during commissioning are reported.

  13. Electron beam stability and beam peak to peak motion data for NSLS X-Ray storage ring

    Energy Technology Data Exchange (ETDEWEB)

    Singh, O.

    1993-07-01

    In the past two years, a significant reduction in electron beam motion has been achieved at the NSLS X-Ray storage ring. The implementation of global analog orbit feedbacks, based on a harmonics correction scheme, has reduced the beam motion globally. Implementation of six local analog feedback systems has reduced the beam motion even further at the corresponding beam line straight sections. This paper presents beam motion measurements, showing the improvement due to the feedback systems. Beam motion is measured using a spectrum analyzer and data is presented at various frequencies, where peaks were observed. Finally, some of the beam motion sources are discussed.

  14. Three-dimensional ordering of cold ion beams in a storage ring: A molecular-dynamics simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Yuri, Yosuke, E-mail: yuri.yosuke@jaea.go.jp [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi Takasaki, Gunma 370-1292 Japan (Japan)

    2015-06-29

    Three-dimensional (3D) ordering of a charged-particle beams circulating in a storage ring is systematically studied with a molecular-dynamics simulation code. An ion beam can exhibit a 3D ordered configuration at ultralow temperature as a result of powerful 3D laser cooling. Various unique characteristics of the ordered beams, different from those of crystalline beams, are revealed in detail, such as the single-particle motion in the transverse and longitudinal directions, and the dependence of the tune depression and the Coulomb coupling constant on the operating points.

  15. Studies of systematic limitations in the EDM searches at storage rings

    CERN Document Server

    Saleev, Artem; Rathmann, Frank

    2015-01-01

    Searches of the electric dipole moment (EDM) at a pure magnetic ring, like COSY, encounter strong background coming from magnetic dipole moment (MDM). The most troubling issue is the MDM spin rotation in the so-called imperfection, radial and longitudinal, B-fields. To study the systematic effects of the imperfection fields at COSY we proposed the original method which makes use of the two static solenoids acting as artificial imperfections. Perturbation of the spin tune caused by the spin kicks in the solenoids probes the systematic effect of cumulative spin rotation in the imperfection fields all over the ring. The spin tune is one of the most precise quantities measured presently at COSY at $10^{-10}$ level. The method has been successfully tested in September 2014 run at COSY, unravelling strength of spin kicks in the ring's imperfection fields at the level of $10^{-3} rad$.

  16. From single photons to milliwatt radiant power-electron storage rings as radiation sources with a high dynamic range

    Energy Technology Data Exchange (ETDEWEB)

    Klein, R.; Thornagel, R.; Ulm, G. [Physikalisch-Technische Bundesanstalt, Berlin (Germany)

    2010-10-15

    The spectral radiant intensity of synchrotron radiation from electron storage rings can be calculated from basic electrodynamic relations (Schwinger equation) and it is directly proportional to the stored electron beam current, i.e. the number of stored electrons. With the necessary equipment installed to measure and control the electron beam current over a wide dynamic range, the radiant intensity of the synchrotron radiation can be adjusted accordingly without changing the spectrum. This is done, e.g., at the Metrology Light Source (MLS), the dedicated electron storage ring of the Physikalisch-Technische Bundesanstalt. The MLS is operated as a primary radiation source standard from the near IR up to the soft x-ray region and its operational parameters can be adjusted and accurately measured in a wide range: the electron beam current can be varied from 1 pA (one stored electron) up to 200 mA and thus the radiant intensity can be changed by more than 11 decades. The photon flux or radiant power for typical angular acceptances can thus be varied from single photons to milliwatts. This is a very powerful tool, e.g., for the characterization of the linearity of the response of radiation detectors or for the calibration of photon counting detectors. In this article we present an overview of past, current and possible future activities exploiting this feature. (authors)

  17. Transient absorption spectroscopy in biology using the Super-ACO storage ring FEL and the synchrotron radiation combination

    CERN Document Server

    Renault, E; De Ninno, G; Garzella, D; Hirsch, M; Nahon, L; Nutarelli, D

    2001-01-01

    The Super-ACO storage ring FEL, covering the UV range down to 300 nm with a high average power (300 mW at 350 nm) together with a high stability and long lifetime, is a unique tool for the performance of users applications. We present here the first pump-probe two color experiments on biological species using a storage ring FEL coupled to the synchrotron radiation. The intense UV pulse of the Super-ACO FEL is used to prepare a high initial concentration of chromophores in their first singlet electronic excited state. The nearby bending magnet synchrotron radiation provides, on the other hand a pulsed, white light continuum (UV-IR), naturally synchronized with the FEL pulses and used to probe the photochemical subsequent events and the associated transient species. We have demonstrated the feasibility with a dye molecule (POPOP) observing a two-color effect, signature of excited state absorption and a temporal signature with Acridine. Applications on various chromophores of biological interest are carried out,...

  18. Environmental Survey preliminary report, Lawrence Berkeley Laboratory, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    The purpose of this report is to present the preliminary findings made during the Environmental Survey, February 22--29, 1988, at the US Department of Energy (DOE) Lawrence Berkeley Laboratory (LBL) in Berkeley, California. The University of California operates the LBL facility for DOE. The LBL Survey is part of the larger DOE-wide Environmental Survey announced by Secretary John S. Herrington on September 18, 1985. The purpose of this effort is to identify, via no fault'' baseline Surveys, existing environmental problems and areas of environmental risk at DOE facilities, and to rank them on a DOE wide basis. This ranking will enable DOE to more effectively establish priorities for addressing environmental problems and allocate the resources necessary to correct them. Because the Survey is no fault'' and is not an audit,'' it is not designed to identify specific isolated incidents of noncompliance or to analyze environmental management practices. Such incidents and/or management practices will, however, be used in the Survey as a means of identifying existing and potential environmental problems. The LBL Survey was conducted by a multidisciplinary team of technical specialists headed and managed by a Team Leader and Assistant Team Leader from DOE's Office of Environmental Audit. A complete list of the LBL Survey participants and their affiliations is provided in Appendix A. 80 refs., 27 figs., 37 tabs.

  19. Two amateur astronomers at Berkeley

    CERN Document Server

    Sparavigna, Amelia Carolina

    2012-01-01

    The book on Mechanics of the Physics at Berkeley, by C. Kittel, W.D. Knight and M.A. Ruderman, is proposing at the end of its first chapter some problems of simple astronomy within the solar system. The discussion begins with two amateur astronomers who set for themselves the goal of determining the diameter and mass of the Sun. Here we discuss the problems proposed by the book and some other matters on ancient and modern astronomical studies of the solar system.

  20. Time structure measurement of the storage ring with the time-resolved X-ray excited optical luminescence method at SSRF

    CERN Document Server

    Zhaohong, Zhang; Song, Xue; Lifang, Zheng

    2014-01-01

    Measuring the time structure of the storage ring on the sample spot inside the experimental hutch is a foundational step during the time-resolved experiments using the pulsed synchrotron X-rays with the time structure defined by the storage ring. In this work, the method of time-resolved X-ray excited optical luminescence was designed and implemented to do the measurement. This method is based on the principle of time-correlated single photon counting techniques. The measurement system consists of a spectrometer with a detector of photomultiplier tube, a timing system, a set of Nuclear Instrument Modules and a luminescent material of Zinc Oxide. The measurement was performed on the X-ray absorbed fine structure spectrum beamline at Shanghai Synchrotron Radiation Facility. The results show that this system can be used to measure the time structure of the storage ring with a precision of less than 1 ns.

  1. Low-Beta Insertions inducing Chromatic Aberrations in Storage Rings and their Local and Global Correction

    CERN Document Server

    Fartoukh, S

    2010-01-01

    The chromatic aberrations induced by low-β insertions can seriously limit the performance of circular colliders. The impact is twofold: (1) a substantial off-momentum beta-beating wave traveling around the ring and leading to a net reduction of the mechanical aperture of the low-beta quadrupoles but also impacting on the hierarchy of the collimator and protection devices of the machine, (2) a huge non-linear chromaticity which, when combined with the magnetic imperfections of the machine, could substantially reduce the momentum acceptance of the ring by pushing slightly off-momentum particles towards non-linear resonances. These effects will be analyzed and illustrated in the framework of the LHC insertions upgrade Phase I [1] and a strategy for correction will be developed, requiring a deep modification of the LHC overall optics.

  2. Low-Beta insertions inducing chromatic aberrations in storage rings and their local and global correction

    CERN Document Server

    Fartoukh, S

    2010-01-01

    The chromatic aberrations induced by low-β insertions can seriously limit the performance of circular colliders. The impact is twofold: (1) a substantial off-momentum beta-beating wave traveling around the ring and leading to a net reduction of the mechanical aperture of the lowbeta quadrupoles but also impacting on the hierarchy of the collimator and protection devices of the machine, (2) a huge non-linear chromaticity which, when combined with the magnetic imperfections of the machine, could substantially reduce the momentum acceptance of the ring by pushing slightly off-momentum particles towards non-linear resonances. These effects will be analyzed and illustrated in the framework of the LHC insertions upgrade Phase I [1] and a strategy for correction will be developed, requiring a deep modification of the LHC overall optics.

  3. Studies of systematic limitations in the EDM searches at storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Saleev, Artem [Institut fuer Kernphysik, Forschungszentrum Juelich (Germany); Collaboration: JEDI-Collaboration

    2014-07-01

    Future experiments on search for the EDM of protons and deuterons at COSY will make use of the E/B- fields to drive the EDM-induced spin precession. One of the options is the so-called radiofrequency Wien-filter. It excerpts zero Lorentz force on the beam, is EDM-transparent, but rotates the magnetic moment (MDM) of the beam particles by which it generates the frequency modulation of the spin tune. This modulation causes a coupling to the EDM precession in the constant motional electric field in the ring and the buildup of the EDM signal under the resonance condition. The troubling issue is that, alongside with the radial motional E-field, the so-called imperfection, radial and longitudinal B-fields from the magnet misalignments abound in the ring. The Wien-filter frequency modulation of the spin tune couples the MDM to the imperfection magnetic fields in precisely the same manner as the EDM couples to the motional electric field in the ring and the imperfection magnetic fields emerge as one of the principal sources of the systematic background to the EDM signal. Upon half a century of experimentation with neutrons, the upper bound of the neutron EDM is at the level of almost 10{sup -12} of the neutron MDM. This indicates a challenge one faces in disentangling the true EDM signal from the MDM induced signal and the compensation for imperfection fields.

  4. 77 FR 37604 - Safety Zone; Fourth of July Fireworks, Berkeley Marina, Berkeley, CA

    Science.gov (United States)

    2012-06-22

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fourth of July Fireworks, Berkeley Marina, Berkeley, CA... enforce the safety zone for the Berkeley Marina Fourth of July Fireworks display in the Captain of the... Berkeley Pier in position 37 51'40'' N, 122 19'19'' W (NAD 83) from 9:30 p.m. until 10:15 p.m. on July...

  5. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xi [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, Xiaobiao [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2016-08-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. Furthermore, the fitting results are used for lattice correction. Our method has been successfully demonstrated on the NSLS-II storage ring.

  6. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    Science.gov (United States)

    Yang, Xi; Huang, Xiaobiao

    2016-08-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. The method has been successfully demonstrated on the NSLS-II storage ring.

  7. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xi [Brookhaven National Laboratory, Upton, Long Island, NY 11973 (United States); Huang, Xiaobiao, E-mail: xiahuang@slac.stanford.edu [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2016-08-21

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. The method has been successfully demonstrated on the NSLS-II storage ring.

  8. Estimation of effective dose caused by stray radiations of photons, electrons and positrons around a small storage ring for a synchrotron radiation facility

    Science.gov (United States)

    Takashima, Y.; Oki, S.; Sugiyama, H.; Kobayakawa, H.

    2005-10-01

    The spatial distribution of the effective dose of photons, electrons and positrons caused by beam loss around a small electron storage ring in a synchrotron radiation source is calculated. We propose a simple formula applicable to calculate the effective dose for storage rings for beam energies ranging from 200 MeV to 5 GeV. The formula is derived from Monte Carlo calculations of radiation flux using the simulation code EGS4. We apply the formula to estimate the effective dose distribution in a small synchrotron radiation facility planned by the Nagoya University.

  9. Time structure measurement of the storage ring with the time-resolved X-ray excited optical luminescence method at SSRF

    OpenAIRE

    Zhaohong, Zhang; Zheng, Jiang; Song, Xue; Lifang, Zheng

    2014-01-01

    Measuring the time structure of the storage ring on the sample spot inside the experimental hutch is a foundational step during the time-resolved experiments using the pulsed synchrotron X-rays with the time structure defined by the storage ring. In this work, the method of time-resolved X-ray excited optical luminescence was designed and implemented to do the measurement. This method is based on the principle of time-correlated single photon counting techniques. The measurement system consis...

  10. Development of Low Level RF Control Systems for Superconducting Heavy Ion Linear Accelerators, Electron Synchrotrons and Storage Rings

    CERN Document Server

    Aminov, Bachtior; Kolesov, Sergej; Pekeler, Michael; Piel, Christian; Piel, Helmut

    2005-01-01

    Since 2001 ACCEL Instruments is supplying low level RF control systems together with turn key cavity systems. The early LLRF systems used the well established technology based on discrete analogue amplitude and phase detectors and modulators. Today analogue LLRF systems can make use of advanced vector demodulators and modulators combined with a fast computer controlled analogue feed back loop. Feed forward control is implemented to operate the RF cavity in an open loop mode or to compensate for predictable perturbations. The paper will introduce the general design philosophy and show how it can be adapted to different tasks as controlling a synchrotron booster nc RF system at 500 MHz, or superconducting storage ring RF cavities, as well as a linear accelerator at 176 MHz formed by a chain of individually driven and controlled superconducting λ/2 cavities.

  11. A fast wire scanner, used to measure the transverse density distribution of beams circulating in an accelerator or storage ring.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Fast wire scanners are used to measure the transverse density distribution of beams circulating in an accelerator or storage ring. In order to minimize blow-up of the beam through multiple Coulomb scattering, the wires are very thin (in the version shown here it is actually a twisted strand of carbon fibres with a total diameter of about 25 microns) and are swept through the beam at high speed (a linear motor, not mounted here, accelerates the wires to up to 20 m/s). One measures either the secondary emission current from the wire, or the signal from a scintillator/photomultiplier combination downstream from the wire scanner receiving the shower from nuclear reactions of beam particles with the wire nuclei. There are four such fast wire scanners in the 26 GeV PS and eight in the 1.4 GeV Booster.

  12. 6 MeV storage ring dedicated to hard X-ray imaging and far-infrared spectroscopy

    Indian Academy of Sciences (India)

    M M Haque; A Moon; T Hirai; H Yamada

    2011-02-01

    The tabletop storage ring, 6 MeV MIRRORCLE, is dedicated to hard X-ray imaging as well as far-infrared (FIR) spectroscopy. In spite of low electron energy, the 6 MeV MIRRORCLE generates hard X-rays ranging from 10 keV up to its electron energy and milliwatt order submillimetre range FIR rays. Bremsstrahlung is the mechanism for the hard X-ray generation. Images produced with 11 × geometrical magnification display a sharply enhanced edge effect when generated using a 25 mm rod electron target. Bright far-infrared is generated in the same way using a conventional synchrotron light source, but with MIRRORCLE the spectral flux is found to be ∼ 1000 times greater than that of a standard thermal source. Partially coherent enhancement is observed in the case of FIR output.

  13. Two-photon exchange contribution in elastic electron-proton scattering, experiment at the VEPP-3 storage ring

    Directory of Open Access Journals (Sweden)

    Nikolenko D.M.

    2014-03-01

    Full Text Available We describe a precise measurement of the ratio of the (e+ p to (e− p elastic scattering cross sections. This comparison is sensitive to the effect of two-photon exchange contributions which may be the cause for inconsistent extractions of the proton form factors obtained using different methods. The experiment was performed at storage ring VEPP–3, Novosibirsk at energies of positron/electron beams of 1.0 and 1.6 GeV with electron/positron scattering angles θ = 65÷105° for the first case and 15÷25° and 55÷75° for the second case. Details of the experiment and the preliminary results are presented.

  14. Single-particle detection of products from atomic and molecular reactions in a cryogenic ion storage ring

    Science.gov (United States)

    Krantz, C.; Novotný, O.; Becker, A.; George, S.; Grieser, M.; Hahn, R. von; Meyer, C.; Schippers, S.; Spruck, K.; Vogel, S.; Wolf, A.

    2017-04-01

    We have used a single-particle detector system, based on secondary electron emission, for counting low-energetic (∼keV/u) massive products originating from atomic and molecular ion reactions in the electrostatic Cryogenic Storage Ring (CSR). The detector is movable within the cryogenic vacuum chamber of CSR, and was used to measure production rates of a variety of charged and neutral daughter particles. In operation at a temperature of ∼ 6 K , the detector is characterised by a high dynamic range, combining a low dark event rate with good high-rate particle counting capability. On-line measurement of the pulse height distributions proved to be an important monitor of the detector response at low temperature. Statistical pulse-height analysis allows to infer the particle detection efficiency of the detector, which has been found to be close to unity also in cryogenic operation at 6 K.

  15. Station on the SR beam of the VEPP-3 storage ring for the study of macromolecular crystal structure (abstract)

    Science.gov (United States)

    Popov, A. N.; Antson, A. A.; Bondarenko, K. P.; Belyaev, V. V.; Harutunyan, E. G.; Kheiker, D. M.; Sheromov, M. A.; Mytnytchenko, S. V.

    1989-07-01

    The station designed to speed up the collection of integral intensity data from protein and virus crystals is constructed on the SR beam of the VEPP-3 storage ring. A flat triangular Si crystal cut at 8° relative to the (111) plane is used to monochromatize the radiation. The monochromator is placed on the automatic goniometer which allows us to obtain the necessary energy of radiation, to make the adjusting turns and displacements, and to bend the crystal in order to achieve focusing in the horizontal plane. All the mechanical drive units are supplied with position sensors based on multiturn potentiometers. A conventional Arndt-Wonacott rotation camera is used to collect structure information. The station also includes an optical bench which can turn about the axis coinciding with that of the monochromator, and a set of slits to cut the background and to form the beam. The ionization camera serves to adjust the monochromator and to monitor the beam.

  16. Multiple-bunch-length operating mode design for a storage ring using hybrid low alpha and harmonic cavity method

    Science.gov (United States)

    Gao, Weiwei; Wang, Lin; Li, Heting

    2017-03-01

    In this paper we design a simultaneous three bunch length operating mode at the HLS-II (Hefei Light Source II) storage ring by installing two harmonic cavities and minimizing the momentum compaction factor. The short bunches (2.6 mm) presented in this work will meet the requirement of coherent millimeter-wave and sub-THz radiation experiments, while the long bunches (20 mm) will efficiently increase the total beam current. Therefore, this multiple-bunch-length operating mode allows present synchrotron users and coherent millimeter-wave users (or sub THz users) to carry out their experiments simultaneously. Since the relatively low energy characteristic of HLS-II we achieve the multiple-bunch-length operating mode without multicell superconducting RF cavities, which is technically feasible.

  17. Measurements of aperture and beam lifetime using movable beam scrapers in Indus-2 electron storage ring.

    Science.gov (United States)

    Kumar, Pradeep; Ghodke, A D; Karnewar, A K; Holikatti, A C; Yadav, S; Puntambekar, T A; Singh, G; Singh, P

    2013-12-01

    In this paper, the measurements of vertical and horizontal aperture which are available for stable beam motion in Indus-2 at beam energy 2.5 GeV using movable beam scrapers are presented. These beam scrapers are installed in one of the long straight sections in the ring. With the movement of beam scrapers towards the beam centre, the beam lifetime is measured. The beam lifetime data obtained from the movement of vertical and horizontal beam scrapers are analyzed. The contribution of beam loss due to beam-gas scattering (vacuum lifetime) and electron-electron scattering within a beam bunch (Touschek lifetime) is separated from the measured beam lifetime at different positions of the beam scrapers. Vertical and horizontal beam sizes at scrapers location are estimated from the scraper movement towards the beam centre in quantum lifetime limit and their values closely agree with measured value obtained using X-ray diagnostic beamline.

  18. Measurements of aperture and beam lifetime using movable beam scrapers in Indus-2 electron storage ring

    Science.gov (United States)

    Kumar, Pradeep; Ghodke, A. D.; Karnewar, A. K.; Holikatti, A. C.; Yadav, S.; Puntambekar, T. A.; Singh, G.; Singh, P.

    2013-12-01

    In this paper, the measurements of vertical and horizontal aperture which are available for stable beam motion in Indus-2 at beam energy 2.5 GeV using movable beam scrapers are presented. These beam scrapers are installed in one of the long straight sections in the ring. With the movement of beam scrapers towards the beam centre, the beam lifetime is measured. The beam lifetime data obtained from the movement of vertical and horizontal beam scrapers are analyzed. The contribution of beam loss due to beam-gas scattering (vacuum lifetime) and electron-electron scattering within a beam bunch (Touschek lifetime) is separated from the measured beam lifetime at different positions of the beam scrapers. Vertical and horizontal beam sizes at scrapers location are estimated from the scraper movement towards the beam centre in quantum lifetime limit and their values closely agree with measured value obtained using X-ray diagnostic beamline.

  19. Non-Gaussian beam dynamics in low energy antiproton storage rings

    Science.gov (United States)

    Resta-López, J.; Hunt, J. R.; Welsch, C. P.

    2016-10-01

    In low energy antiproton facilities, where electron cooling is fundamental, the cooling forces together with heating phenomena causing emittance blow-up, such as Intra Beam Scattering (IBS), result in highly non-Gaussian beam distributions. In these cases, a precise simulation of IBS effects is essential to realistically evaluate the long term beam evolution, taking into account the non-Gaussian characteristics of the beam. Here, we analyse the beam dynamics in the Extra Low ENergy Antiproton ring (ELENA), which is a new small synchrotron currently being constructed at CERN to decelerate antiprotons to energies as low as 100 keV. Simulations are performed using the code BETACOOL, comparing different models of IBS.

  20. Lifetime improvement and beam stabilization by longitudinal phase modulation at the DELTA electron storage ring; Lebensdauerverbesserung und Strahlstabilisierung durch longitudinale Phasenmodulation am Elektronenspreicherring DELTA

    Energy Technology Data Exchange (ETDEWEB)

    Fuersch, Jonathan

    2014-10-16

    In DELTA especially at high beam currents often the occurence of an instability of a longitudinal oscillation mode is observed. In the framework of the present thesis first with different procedure the cause of the longitudinal oscillation mode, which is especially strongly excited at high beam currents, is searched for. Thereby connections between the occurrence of this mode and parameters from the region of the storage-ring high-frequency system is observed. It is shown by comparison of different procedures, simulation calculations, and experimental pre-examinations, that especially by a phase modulation of the storage-ring high frequency an essential improvement of especially the longitudinal beam stability and the beam lifetime can be reached. For the durable and reliable improvement of these beam properties in the framework of the present thesis a system for the longitudinal phase modulation of the after-acceleration voltage in the cavity resonator of the DELTA storage ring is concipated, developed, constructed, taken in operation, and tested. Finally the results aimed hereby are presented and discussed.

  1. Modeling the effects of a flat wiggler on a storage ring beam

    Energy Technology Data Exchange (ETDEWEB)

    Helm, R.H.

    1978-06-01

    The purpose of the present note is to show how the various effects of the wiggler may be modeled in a simple way suitable for use in machine control. It will be seen that in general a total of about 17 functions are involved. However, in typical designs many of these functions vanish identically because of symmetries, and others are neglibly small. Furthermore, each of the functions may be modeled quite accurately by a single power law in (B/sub o//E)/sup n/ where B is a measure of the field excitation. E is the beam energy, and n is an integer which takes on values of either 0, 2, 3, 4, for 5 for the different functions. Magnet saturation may cause the field distribution to vary with excitation so that the series coefficients would vary slowly with B/sub o/. A computer program has been used to obtain numerical results for typical wiggler designs. In practice, the required functions could be determined either by computer analysis of the measured field data, or by experimental calibration using the stored beam in the ring. 9 refs., 3 figs., 11 tabs.

  2. Berkeley-Madonna implementation of Ikeda's model.

    Science.gov (United States)

    Fontecave-Jallon, J; Baconnier, P

    2007-01-01

    Starting from one model, we check the possibility of using Berkeley-Madonna software to transpose and simulate some existing biological integrated models. The considered model is the one of Ikeda et al., proposed in 1979, which treats of fluid regulation and which is very well described mathematically in the original paper. Despite a few mistakes or bugs, the model has been easily and successfully implemented under Berkeley-Madonna. We recover the same simulation results as Ikeda and new simulations can now easily be carried out, thanks to the user-friendly qualities of Berkeley-Madonna.

  3. The anticentre old open clusters Berkeley 27, Berkeley 34, and Berkeley 36: new additions to the BOCCE project

    CERN Document Server

    Donati, P; Cignoni, M; Cocozza, G; Tosi, M

    2012-01-01

    In this paper we present the investigation of the evolutionary status of three open clusters: Berkeley 27, Berkeley 34, and Berkeley 36, all located in the Galactic anti-centre direction. All of them were observed with SUSI2@NTT using the Bessel B, V, and I filters. The cluster parameters have been obtained using the synthetic colour-magnitude diagram (CMD) method i.e. the direct comparison of the observational CMDs with a library of synthetic CMDs generated with different evolutionary sets (Padova, FRANEC, and FST). This analysis shows that Berkeley 27 has an age between 1.5 and 1.7 Gyr, a reddening E(B-V) in the range 0.40 and 0.50, and a distance modulus (m-M)_0 between 13.1 and 13.3; Berkeley 34 is older with an age in the range 2.1 and 2.5 Gyr, E(B-V) between 0.57 and 0.64, and (m-M)_0 between 14.1 and 14.3; Berkeley 36, with an age between 7.0 and 7.5 Gyr, has a reddening E(B-V)~0.50 and a distance modulus (m-M)_0 between 13.1 and 13.2. For all the clusters our analysis suggests a sub-solar metallicity ...

  4. Berkeley Lab Laser Accelerator (BELLA) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Berkeley Lab Laser Accelerator (BELLA) facility (formerly LOASIS) develops advanced accelerators and radiation sources. High gradient (1-100 GV/m) laser-plasma...

  5. External meeting - Geneva University: Proposal to measure the muon electric dipole moment with a compact storage ring at PSI

    CERN Multimedia

    2007-01-01

    GENEVA UNIVERSITY ECOLE DE PHYSIQUE Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 ? Tél : 022 379 62 73 - Fax: 022 379 69 92 Wednesday 16th May  2007 PARTICLE PHYSICS SEMINAR at 17:00 - Stückelberg Auditorium Proposal to measure the muon electric dipole moment with a compact storage ring at PSI by Dr. Thomas Schietinger, PSI - Villigen In the Standard Model, lepton electric dipole moments (EDM) arise from the CP-violating phase in the CKM matrix at the three-loop level only, resulting in values that are many orders of magnitude below the sensitivity of current and future experiments. Lepton EDMs therefore offer an excellent opportunity to discover unambiguous evidence for new CP-violating phases, as called for by the baryon-antibaryon asymmetry of the universe. The muon EDM is one of the least constrained fundamental properties in elementary particle physics. We propose to utilize the large available flux of polarized muons at PSI to search for a muon EDM ...

  6. Observation of Electron Cloud Instabilities and Emittance Dilution at the Cornell Electron-Positron Storage Ring Test Accelerator

    Science.gov (United States)

    Holtzapple, R. L.; Billing, M. G.; Campbell, R. C.; Dugan, G. F.; Flanagan, J.; McArdle, K. E.; Miller, M. I.; Palmer, M. A.; Ramirez, G. A.; Sonnad, K. G.; Totten, M. M.; Tucker, S. L.; Williams, H. A.

    2016-04-01

    Electron cloud related emittance dilution and instabilities of bunch trains limit the performance of high intensity circular colliders. One of the key goals of the Cornell electron-positron storage ring Test Accelerator (CesrTA) research program is to improve our understanding of how the electron cloud alters the dynamics of bunches within the train. Single bunch beam diagnotics have been developed to measure the beam spectra, vertical beam size, two important dynamical effects of beams interacting with the electron cloud, for bunch trains on a turn-by-turn basis. Experiments have been performed at CesrTA to probe the interaction of the electron cloud with stored positron bunch trains. The purpose of these experiments was to characterize the dependence of beam-electron cloud interactions on the machine parameters such as bunch spacing, vertical chromaticity, and bunch current. The beam dynamics of the stored beam, in the presence of the electron cloud, was quantified using: 1) a gated beam position monitor (BPM) and spectrum analyzer to measure the bunch-by-bunch frequency spectrum of the bunch trains; 2) an x-ray beam size monitor to record the bunch-by-bunch, turn-by-turn vertical size of each bunch within the trains. In this paper we report on the observations from these experiments and analyze the effects of the electron cloud on the stability of bunches in a train under many different operational conditions.

  7. Ray Tracing through the Edge Focusing of Rectangular Benders and an Improved Model for the Los Alamos Proton Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Kolski, Jeffrey S. [Los Alamos National Laboratory; Barlow, David B. [Los Alamos National Laboratory; Macek, Robert J. [Los Alamos National Laboratory; McCrady, Rodney C. [Los Alamos National Laboratory

    2011-01-01

    Particle ray tracing through simulated 3D magnetic fields was executed to investigate the effective quadrupole strength of the edge focusing of the rectangular bending magnets in the Los Alamos Proton Storage Ring (PSR). The particle rays receive a kick in the edge field of the rectangular dipole. A focal length may be calculated from the particle tracking and related to the fringe field integral (FINT) model parameter. This tech note introduces the baseline lattice model of the PSR and motivates the need for an improvement in the baseline model's vertical tune prediction, which differs from measurement by .05. An improved model of the PSR is created by modifying the fringe field integral parameter to those suggested by the ray tracing investigation. This improved model is then verified against measurement at the nominal PSR operating set point and at set points far away from the nominal operating conditions. Lastly, Linear Optics from Closed Orbits (LOCO) is employed in an orbit response matrix method for model improvement to verify the quadrupole strengths of the improved model.

  8. A Design Report of the Baseline for PEP-X: an Ultra-Low Emittance Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Bane, Karl; Bertsche, Kirk; Cai, Yunhai; Chao, Alex; Corbett, Willian; Fox, John; Hettel, Robert; Huang, Xiaobiao; Huang, Zhirong; Ng, Cho-Kuen; Nosochkov, Yuri; Novokhatski, Sasha; Radedeau, Thomas; Raubenheimer, Tor; Rivetta, Claudio; Safranek, James; Seeman, John; Stohr, Joachim; Stupakov, Gennady; Wang, Lanfa; Wang, Min-Huey; /SLAC

    2010-06-02

    Over the past year, we have worked out a baseline design for PEP-X, as an ultra-low emittance storage ring that could reside in the existing 2.2-km PEPII tunnel. The design features a hybrid lattice with double bend achromat (DBA) cells in two arcs and theoretical minimum emittance (TME) cells in the remaining four arcs. Damping wigglers are used to reduce the horizontal emittance to 86 pm-rad at zero current for a 4.5 GeV electron beam. At a design current of 1.5 A, the horizontal emittance increases, due to intrabeam scattering, to 164 pm-rad when the vertical emittance is maintained at a diffraction limited 8 pm-rad. The baseline design will produce photon beams achieving a brightness of 10{sup 22} (ph/s/mm{sup 2}/mrad{sup 2}/0.1% BW) at 10 keV in a 3.5-m conventional planar undulator. Our study shows that an optimized lattice has adequate dynamic aperture, while accommodating a conventional off-axis injection system. In this report, we present the results of study, including the lattice properties, nonlinear dynamics, intra-beam scattering and Touschek lifetime, RF system, and collective instabilities. Finally, we discuss the possibility of partial lasing at soft X-ray wavelengths using a long undulator in a straight section.

  9. A Monte-Carlo simulation of the equilibrium beam polarization in ultra-high energy electron(positron) storage rings

    CERN Document Server

    Duan, Zhe; Barber, Desmond P; Qin, Qing

    2015-01-01

    With the recently emerging global interest in building a next generation of circular electron-positron colliders to study the properties of the Higgs boson, and other important topics in particle physics at ultra-high beam energies, it is also important to pursue the possibility of implementing polarized beams at this energy scale. It is therefore necessary to set up simulation tools to evaluate the beam polarization at these ultra-high beam energies. In this paper, a Monte-Carlo simulation of the equilibrium beam polarization based on the Polymorphic Tracking Code(PTC) is described. The simulations are for a model storage ring with parameters similar to those of proposed circular colliders in this energy range, and they are compared with the suggestion that there are different regimes for the spin dynamics underlying the polarization of a beam in the presence of synchrotron radiation at ultra-high beam energies. In particular, it has been suggested that the so-called "correlated" crossing of spin resonances ...

  10. Charge and frequency resolved isochronous mass spectrometry in storage rings: First direct mass measurement of the short-lived neutron-deficient $^{51}$Co nuclide

    CERN Document Server

    Shuai, P; Tu, X L; Zhang, Y H; Sun, B H; Litvinov, Yu A; Yan, X L; Blaum, K; Wang, M; Zhou, X H; He, J J; Sun, Y; Kaneko, K; Yuan, Y J; Xia, J W; Yang, J C; Audi, G; Chen, X C; Jia, G B; Hu, Z G; Ma, X W; Mao, R S; Mei, B; Sun, Z Y; Wang, S T; Xiao, G Q; Xu, X; Yamaguchi, T; Yamaguchi, Y; Zang, Y D; Zhao, H W; Zhao, T C; Zhang, W; Zhan, W L

    2014-01-01

    Revolution frequency measurements of individual ions in storage rings require sophisticated timing detectors. One of common approaches for such detectors is the detection of secondary electrons released from a thin foil due to penetration of the stored ions. A new method based on the analysis of intensities of secondary electrons was developed which enables determination of the charge of each ion simultaneously with the measurement of its revolution frequency. Although the mass-over-charge ratios of $^{51}$Co$^{27+}$ and $^{34}$Ar$^{18+}$ ions are almost identical, and therefore, the ions can not be resolved in a storage ring, by applying the new method the mass excess of the short-lived $^{51}$Co is determined for the first time to be ME($^{51}$Co)=-27342(48) keV. Shell-model calculations in the $fp$-shell nuclei compared to the new data indicate the need to include isospin-nonconserving forces.

  11. Spin rotation and birefringence effect for a particle in a high energy storage ring and measurement of the real part of the coherent elastic zero-angle scattering amplitude, electric and magnetic polarizabilities

    CERN Document Server

    Baryshevsky, V G

    2005-01-01

    In the present paper the equations for the spin evolution of a particle in a storage ring are analyzed considering contributions from the tensor electric and magnetic polarizabilities of the particle. Study of spin rotation and birefringence effect for a particle in a high energy storage ring provides for measurement as the real part of the coherent elastic zero-angle scattering amplitude as well as tensor electric and magnetic polarizabilities. We proposed the method for measurement the real part of the elastic coherent zero-angle scattering amplitude of particles and nuclei in a storage ring by the paramagnetic resonance in the periodical in time nuclear pseudoelectric and pseudomagnetic fields.

  12. Analytical treatment of the nonlinear electron cloud effect and the combined effects with beam-beam and space charge nonlinear forces in storage rings

    Institute of Scientific and Technical Information of China (English)

    GAO Jie

    2009-01-01

    In this paper we treat first some nonlinear beam dynamics problems in storage rings, such as beam dynamic apertures due to magnetic multipoles, wiggles, beam-beam effects, nonlinear space charge effect, and then nonlinear electron cloud effect combined with beam-beam and space charge effects, analytically. This analytical treatment is applied to BEPC Ⅱ. The corresponding analytical expressions developed in this paper are useful both in understanding the physics behind these problems and also in making practical quick hand estimations.

  13. Calculations of neutron and photon source terms and attenuation profiles for the generic design of the SPEAR3 storage ring shield.

    Science.gov (United States)

    Rokni, S H; Khater, H; Liu, J C; Mao, S; Vincke, H

    2005-01-01

    The FLUKA Monte Carlo particle generation and transport code was used to calculate shielding requirements for the 3 GeV, 500 mA SPEAR3 storage ring at the Stanford Synchrotron Radiation Laboratory. The photon and neutron dose equivalent source term data were simulated for a 3 GeV electron beam interacting with two typical target/shielding geometries in the ring. The targets simulated are a rectangular block of 0.7 cm thick copper and a 5 cm thick iron block, both tilted at 1 degree relative to the beam direction. Attenuation profiles for neutrons and photons in concrete and lead as a function of angle at different shield thicknesses were calculated. The first, second and equilibrium attenuation lengths of photons and neutrons in the shield materials are derived from the attenuation profiles. The source term data and the attenuation lengths were then used to evaluate the shielding requirements for the ratchet walls of all front-ends of the SPEAR3 storage ring.

  14. Investigation and optimization of transverse non-linear beam dynamics in the high-energy storage ring HESR

    Energy Technology Data Exchange (ETDEWEB)

    Welsch, Dominic Markus

    2010-03-10

    The High-Energy Storage Ring (HESR) is part of the upcoming Facility for Antiproton and Ion Research (FAIR) which is planned as a major extension to the present facility of the Helmholtzzentrum fuer Schwerionenforschung (GSI) in Darmstadt. The HESR will provide antiprotons in the momentum range from 1.5 to 15 GeV/c for the internal target experiment PANDA. The demanding requirements of PANDA in terms of beam quality and luminosity together with a limited production rate of antiprotons call for a long beam life time and a minimum of beam loss. Therefore, an effective closed orbit correction and a sufficiently large dynamic aperture of the HESR are crucial. With this thesis I present my work on both of these topics. The expected misalignments of beam guiding magnets have been estimated and used to simulate the closed orbit in the HESR. A closed orbit correction scheme has been developed for different ion optical settings of the HESR and numerical simulations have been performed to validate the scheme. The proposed closed orbit correction method which uses the orbit response matrix has been benchmarked at the Cooler Synchrotron COSY of the Forschungszentrum Juelich. A chromaticity correction scheme for the HESR consisting of sextupole magnets has been developed to reduce tune spread and thus to minimize the emittance growth caused by betatron resonances. The chromaticity correction scheme has been optimized through dynamic aperture calculations. The estimated field errors of the HESR dipole and quadrupole magnets have been included in the non-linear beam dynamics studies. Investigations concerning their optimization have been carried out. The ion optical settings of the HESR have been improved using dynamic aperture calculations and the technique of frequency map analysis. The related diffusion coefficient was also used to predict long-term stability based on short-term particle tracking. With a reasonable reduction of the quadrupole magnets field errors and a

  15. Investigation of transient processes at the DELTA electron storage ring using a digital bunch-by-bunch feedback system

    Energy Technology Data Exchange (ETDEWEB)

    Hoener, Markus

    2015-07-01

    At the 1.5-GeV synchrotron radiation source DELTA, operated by the TU Dortmund University, intensive synchrotron radiation in the spectral range from hard X-rays to THz radiation is generated by the circular deflection of highly relativistic electron bunches. Interacting with the vacuum chamber wall, the electron bunches create electric fields, which can act back on subsequent bunches. With increasing beam current, the excitation is enhanced so that the electron beam is unstable, which means that the electron bunches oscillate longitudinally or transversely relative to their reference position. The oscillations reduce the quality of the synchrotron radiation and limit the maximum storable beam current. Within the scope of this thesis, the beam instabilities at the storage ring were systematically investigated. A digital bunch-by-bunch feedback system was installed and commissioned, which allows to detect and digitize the position of each electron bunch at each turn. Based on the input signal, a correction signal is calculated in order to suppress transverse and longitudinal oscillation of the bunches. In addition, it is possible to excite dedicated bunches. The systematic excitation of all coupled-bunch modes allowed for the first time to determine the damping rates of all 192 eigenmodes of the electron beam. The current dependence of the damping rates was investigated and an instability threshold was found. Besides the investigation of multibunch instabilities, single-bunch instabilities are discussed. In addition, the acquisition unit of the digital feedback system can be triggered on external events. This was used to investigate the injection process and beam losses. It was shown that the transverse feedback system increases the injection efficiency. Another aspect of this thesis is the improvement of the signal quality of ultrashort coherent synchrotron radiation pulses, which are generated by the short-pulse facility at DELTA. The short-pulse facility is based

  16. THE YOUNG OPEN CLUSTER BERKELEY 55

    Energy Technology Data Exchange (ETDEWEB)

    Negueruela, Ignacio; Marco, Amparo, E-mail: ignacio.negueruela@ua.es, E-mail: amparo.marco@ua.es [Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, Apdo. 99, E-03080 Alicante (Spain)

    2012-02-15

    We present UBV photometry of the highly reddened and poorly studied open cluster Berkeley 55, revealing an important population of B-type stars and several evolved stars of high luminosity. Intermediate-resolution far-red spectra of several candidate members confirm the presence of one F-type supergiant and six late supergiants or bright giants. The brightest blue stars are mid-B giants. Spectroscopic and photometric analyses indicate an age 50 {+-} 10 Myr. The cluster is located at a distance d Almost-Equal-To 4 kpc, consistent with other tracers of the Perseus Arm in this direction. Berkeley 55 is thus a moderately young open cluster with a sizable population of candidate red (super)giant members, which can provide valuable information about the evolution of intermediate-mass stars.

  17. C. Judson King of UC Berkeley

    Energy Technology Data Exchange (ETDEWEB)

    Prausnitz, John

    2005-06-01

    In the middle of the UC Berkeley campus, next to the Main Library, South Hall is the last surviving building from the original campus, founded about 135 years ago. A tiny tree-shaded appendix to this venerated classical building houses Berkeley's Center for Studies in Higher Education, directed by C. Judson King, former Provost and Senior Vice President--Academic Affairs of the ten-campus University of California and long-time Professor of Chemical Engineering at Berkeley. Jud came to Berkeley in 1963 as assistant professor of chemical engineering, following receipt of a doctor's degree from MIT and a subsequent short appointment as director of the MIT chemical engineering practice school station at what was then Esso (now Exxon) in New Jersey. His undergraduate degree is from Yale. Starting with his MIT doctoral dissertation on gas absorption, Jud has devoted much of his professional career to separation processes. His teaching and research activities have been primarily concerned with separation of mixtures with emphasis on liquid-liquid extraction and drying. As a consultant to Procter and Gamble, he contributed to the technology of making instant coffee. His life-long activities in hiking and camping stimulated Jud's interest in the manufacture of freeze-dried foods (e.g. turkey meat) to minimize the weight of his hiking back-pack. Jud is internationally known not only for his many research publications but even more, for his acclaimed textbook ''Separation Processses'' (McGraw-Hill, second edition 1980) that is used in standard chemical engineering courses in the US and abroad.

  18. Lawrence Berkeley Laboratory 1993 Site Environmental Report

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    This annual Site Environmental Report summarizes Lawrence Berkeley Laboratory`s (LBL`s) environmental activities in calendar year (CY) 1993. The purpose of this report is to characterize site environmental management performance, confirm compliance status with environmental standards and requirements, and highlight significant programs and efforts. Its format and content are consistent with the requirements of the US Department of Energy (DOE) Order 5400.1, General Environmental Protection Program.

  19. Berkeley Lab Computing Sciences: Accelerating Scientific Discovery

    OpenAIRE

    Hules, John A.

    2009-01-01

    Scientists today rely on advances in computer science, mathematics, and computational science, as well as large-scale computing and networking facilities, to increase our understanding of ourselves, our planet, and our universe. Berkeley Lab's Computing Sciences organization researches, develops, and deploys new tools and technologies to meet these needs and to advance research in such areas as global climate change, combustion, fusion energy, nanotechnology, biology, and astrophysics.

  20. First Measurement of the $^{96}$Ru(p,$\\gamma$)$^{97}$Rh Cross Section for the p-Process with a Storage Ring

    CERN Document Server

    Mei, Bo; Bishop, Shawn; Blaum, Klaus; Boretzky, Konstanze; Bosch, Fritz; Brandau, Carsten; Bräuning, Harald; Davinson, Thomas; Dillmann, Iris; Dimopoulou, Christina; Ershova, Olga; Fülöp, Zsolt; Geissel, Hans; Glorius, Jan; Gyürky, György; Heil, Michael; Käppeler, Franz; Kelic-Heil, Aleksandra; Kozhuharov, Christophor; Langer, Christoph; Bleis, Tudi Le; Litvinov, Yuri; Lotay, Gavin; Marganiec, Justyna; Münzenberg, Gottfried; Nolden, Fritz; Petridis, Nikolaos; Plag, Ralf; Popp, Ulrich; Rastrepina, Ganna; Reifarth, René; Riese, Björn; Rigollet, Catherine; Scheidenberger, Christoph; Simon, Haik; Sonnabend, Kerstin; Steck, Markus; Stöhlke, Thomas; Szücs, Tamás; Sümmerer, Klaus; Weber, Günter; Weick, Helmut; Winters, Danyal; Winters, Natalya; Woods, Philip; Zhong, Qiping

    2015-01-01

    This work presents a direct measurement of the $^{96}$Ru($p, \\gamma$)$^{97}$Rh cross section via a novel technique using a storage ring, which opens opportunities for reaction measurements on unstable nuclei. A proof-of-principle experiment was performed at the storage ring ESR at GSI in Darmstadt, where circulating $^{96}$Ru ions interacted repeatedly with a hydrogen target. The $^{96}$Ru($p, \\gamma$)$^{97}$Rh cross section between 9 and 11 MeV has been determined using two independent normalization methods. As key ingredients in Hauser-Feshbach calculations, the $\\gamma$-ray strength function as well as the level density model can be pinned down with the measured ($p, \\gamma$) cross section. Furthermore, the proton optical potential can be optimized after the uncertainties from the $\\gamma$-ray strength function and the level density have been removed. As a result, a constrained $^{96}$Ru($p, \\gamma$)$^{97}$Rh reaction rate over a wide temperature range is recommended for $p$-process network calculations.

  1. Spatial distribution and polarization of gamma-rays generated via Compton backscattering in the Duke/OK-4 storage ring FEL

    CERN Document Server

    Park, S H; Tornow, W; Montgomery, C

    2001-01-01

    Beams of nearly monochromatic gamma-rays are produced via intracavity Compton backscattering in the OK-4/Duke storage ring FEL, the high-intensity gamma-ray source (HI gamma S). Presently, HI gamma S generates gamma-ray beams with an energy tunable from 2 to 58 MeV and a maximum flux of 5x10 sup 7 gamma-rays per second. The gamma-rays are linearly polarized with a degree of polarization close to 100% (V.N. Litvinenko, et al., Predictions and expected performance for the VUV OK-5/Duke Storage Ring FEL with variable polarization, Nucl. Instr. and Meth. A, to be published in this proceeding) and they are collimated to pencil-like semi-monoenergetic beams with RMS energy spreads as low as 0.2%. The detailed theoretical and experimental studies of the gamma-ray beam quality were conducted during the last two years (S.H. Park, Thesis, Duke University, Durham, NC, USA, 2000). In this paper, we present the theoretical analysis and the experimental results on the spatial distribution and polarization of gamma-rays fro...

  2. Non-linear beam-beam forces in storage rings. Particular analysis for S. S. C. and L. H. C. parameters

    Energy Technology Data Exchange (ETDEWEB)

    Pusterla, M.; Servizi, G.; Turchetti, G.

    1985-10-01

    Theoretical models, suitable for description of the long behaviour of bunched and unbunched beams of particles in accelerators and storage rings, are becoming more and more appreciated by physicists that want a high luminosity joined with the stability of the beams. Such a point is going to be particulary important for the next generation machines as L.E.P., S.S.C. and L.H.C. In this note we are giving a simplified analysis of the beam-beam non-linear effects for proton colliders on the basis of the latest designs (we think of S.S.C. and L.H.C.). Before doing that, however, we like to consider the general features of the dynamical approaches that describe the beam-beam forces both for the proton proton rings (fixed angle collision) and for proton-antiproton or electronpositron rings (head-on collisions): they follow directly from the recent developments of non-linear classical mechanics, namely the K.A.M. theorem and the transition to a chaotic motion in deterministic mechanical systems.

  3. Suppressing the Coffee-Ring Effect in Semitransparent MnO2 Film for a High-Performance Solar-Powered Energy Storage Window.

    Science.gov (United States)

    Jin, Huanyu; Qian, Jiasheng; Zhou, Limin; Yuan, Jikang; Huang, Haitao; Wang, Yu; Tang, Wing Man; Chan, Helen Lai Wa

    2016-04-13

    We introduce a simple and effective method to deposit a highly uniform and semitransparent MnO2 film without coffee-ring effect (CRE) by adding ethanol into MnO2 ink for transparent capacitive energy storage devices. By carefully controlling the amount of ethanol added in the MnO2 droplet, we could significantly reduce the CRE and thus improve the film uniformity. The electrochemical properties of supercapacitor (SC) devices using semitransparent MnO2 film electrodes with or without CRE were measured and compared. The SC device without CRE shows a superior capacitance, high rate capability, and lower contact resistance. The CRE-free device could achieve a considerable volumetric capacitance of 112.2 F cm(-3), resulting in a high volumetric energy density and power density of 10 mWh cm(-3) and 8.6 W cm(-3), respectively. For practical consideration, both flexible SC and large-area rigid SC devices were fabricated to demonstrate their potential for flexible transparent electronic application and capacitive energy-storage window application. Moreover, a solar-powered energy storage window which consists of a commercial solar cell and our studied semitransparent MnO2-film-based SCs was assembled. These SCs could be charged by the solar cell and light up a light emitting diode (LED), demonstrating their potential for self-powered systems and energy-efficient buildings.

  4. Investigation of the isochronous mode of the experimental storage ring (ESR) and the collector ring (CR). Decay spectroscopy of highly charged stored {sup 140}Pr ions at the FRS-ESR facility

    Energy Technology Data Exchange (ETDEWEB)

    Litvinov, Sergey A.

    2008-11-15

    The combination of the present fragment separator FRS and the cooler-storage ring ESR at GSI provides conditions for accurate mass and unique half-life measurements of exotic nuclei. A major part of this doctoral work has been devoted to investigations of the isochronous ion-optical operating mode of the present ESR facility and the planned Collector Ring (CR) facility at FAIR. A detailed ion-optical study of the isochronous storage ring with the emphasis on the main parameters has been done. For example, a simple scaling law providing a quantitative estimate for the mass resolving power as a function of the transverse acceptance has been derived. The ion-optical matching of the FRS-ESR has been calculated and experimentally verified for both the standard and the isochronous operating modes of the ESR. In addition, the dispersion function of a stored ion beam has been measured for both ion-optical modes at the straight section. The improved setting for higher transmission in the standard mode has been used in an experiment on the half-life measurements of highly-charged ions. Orbital electron capture (EC) and/or {beta}{sup +}-decay rates of {sup 140}Pr ions with zero-, one- and two- bound electrons have been measured. A complementary future study of EC-decay in highly-charged {sup 64}Cu ions is discussed. Based on the present experience, the ion-optical matching between the future in-flight fragment separator Super-FRS and the CR has been calculated. The isochronous mode of the CR has been calculated. A dedicated Monte-Carlo code (ISOCHRON) has been developed in order to investigate the influence of the transverse acceptance, the closed orbit distortions, the fringe fields of the quadrupoles, the magnetic field imperfections of the magnets on the mass resolving power. The influence of chromaticity on the isochronicity has been investigated. The correction of the chromaticity and of second-order isochronicity has been performed employing sextupole magnets in the

  5. 上海光源储存环线性模型校正%Linear Optics Model Correction at SSRF Storage Ring

    Institute of Scientific and Technical Information of China (English)

    张满洲; 后接; 李浩虎; 陈建辉; 田顺强; 张文志

    2011-01-01

    上海光源是我国刚刚建成的一台第三代中能同步辐射光源。为使得上海光源能够严格工作在设计状态下,在调试过程中进行了一系列线性模型的校正,主要包括闭轨校正、基于束流准直(BBA)校正、LOCO参数校正和线性耦合校正。经过反复的线性模型校正以后,上海光源储存环的闭轨畸变均方根误差在水平和垂直两个方向可以分别控制到50和60μm的水平,包络函数畸变和色散函数畸变都可以控制到小于1%的状态,工作点和束流发射度基本上校正到了设计值。线性耦合校正能够方便地将储存环的耦合度从0.02%调节到2%左右。调试结果表明,上海光源采取的这一套线性模型校正方法,能够有效地将上海光源的工作状态校正到设计状态,并且为其他模式的调节奠定了基础。%In the commissioning stage of Shanghai Synchrotron Radiation Facility(SSRF) storage ring,several methods were used to correct the linear optics.Beam Based Alignment(BBA) was used for BPM-Quadrupole offsets measurement;Response matrix was used for orbit correction;LOCO was used for linear optics fitting,and quadrupoles strength were adjusted to correction the beta function;coupling was measured and corrected by skew quadrupoles.After correction,closed orbit are reduced to 50/60 μm in hortizontal and vertical plane;β beating and dispersion errors are less than 1%;betatron tune and emmittance are closed to the design value;betatron coupling also can be adjusted from 0.02% to 2%.These methods have been proved to be useful for storage ring calibrations,with the help of these methods,SSRF storage ring can be tuned to the design model and other model easily.

  6. Lawrence Berkeley Laboratory 1994 site environmental report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The 1994 Site Environmental Report summarizes environmental activities at Lawrence Berkeley Laboratory (LBL) for the calendar year (CY) 1994. The report strives to present environmental data in a manner that characterizes the performance and compliance status of the Laboratory`s environmental management programs when measured against regulatory standards and DOE requirements. The report also discusses significant highlight and planning efforts of these programs. The format and content of the report are consistent with the requirements of the U.S. Department of Energy (DOE) Order 5400.1, General Environmental Protection Program.

  7. Three new bricks in the wall: Berkeley 23, Berkeley 31, and King 8

    CERN Document Server

    Cignoni, Michele; Bragaglia, Angela; Tosi, Monica

    2011-01-01

    A comprehensive census of Galactic open cluster properties places unique constraints on the Galactic disc structure and evolution. In this framework we investigate the evolutionary status of three poorly-studied open clusters, Berkeley 31, Berkeley 23 and King 8, all located in the Galactic anti-centre direction. To this aim, we make use of deep LBT observations, reaching more than 6 mag below the main sequence Turn- Off. To determine the cluster parameters, namely age, metallicity, distance, reddening and binary fraction, we compare the observational colour-magnitude diagrams (CMDs) with a library of synthetic CMDs generated with different evolutionary sets (Padova, FRANEC and FST) and metallicities. We find that Berkeley 31 is relatively old, with an age between 2.3 and 2.9 Gyr, and rather high above the Galactic plane, at about 700 pc. Berkeley 23 and King 8 are younger, with best fitting ages in the range 1.1-1.3 Gyr and 0.8-1.3 Gyr, respectively. The position above the Galactic plane is about 500- 600 pc...

  8. Investigation by techniques of electron stimulated desorption of the merits of glow discharge cleaning of the surfaces of vacuum chambers at the CERN intersecting storage rings

    CERN Document Server

    Jones, A W; Williams, E M

    1973-01-01

    To provide surface cleaning of the CERN intersecting storage rings, in which the pressure is below 10/sup -10/ torr over a 2 km length of mostly elliptical pipe (160*52 mm), ion bombardment during a glow discharge has been utilized. The discharge in argon at a pressure of about 3*10/sup -2/ torr was carried out intermittently in the course of a 15 h bake-out at 300 degrees C. Subsequent electron scrubbing enabled the electron desorption efficiency of the surface of the ISR vacuum chambers to be reduced by two to three orders of magnitude. Information is given on the apparatus used and the procedure adopted, together with a discussion of the diagnostic technique and a consideration of the action of the discharge cleaning. (15 refs).

  9. Statistical analysis of the limitation of half integer resonances on the available momentum acceptance of a diffraction-limited storage ring

    CERN Document Server

    Jiao, Yi

    2016-01-01

    In a diffraction-limited storage ring (DLSR), the momentum acceptance (MA) might be limited by the half integer resonances (HIRs) excited by focusing errors, associated with the large detuning terms from the strong focusing and strong sextupoles required for an ultralow emittance. Taking the High Energy Photon Source (HEPS) as an example and through statistical analysis, we found that the horizontal HIRs have stronger impact on dynamics than the vertical ones; and the probability of MA reduction caused by a HIR is closely correlated with the level of the beta beats at the same plane, but independent of the error sources. For the HEPS design, to reach a small MA-reduction probability of about 1%, the rms amplitude of the beta beats at the nominal tunes should be kept below 1.5% horizontally and 2.5% vertically. The presented analysis can provide useful reference for other DLSR designs.

  10. Careers in Data Science: A Berkeley Perspective

    Science.gov (United States)

    Koy, K.

    2015-12-01

    Last year, I took on an amazing opportunity to serve as the Executive Director of the new Berkeley Institute for Data Science (BIDS). After a 15-year career working with geospatial data to advance our understanding of the environment, I have been presented with a unique opportunity through BIDS to work with talented researchers from a wide variety of backgrounds. Founded in 2013, BIDS is a central hub of research and education at UC Berkeley designed to facilitate and nurture data-intensive science. We are building a community centered on a cohort of talented data science fellows and senior fellows who are representative of the world-class researchers from across our campus and are leading the data science revolution within their disciplines. Our initiatives are designed to bring together broad constituents of the data science community, including domain experts from the life, social, and physical sciences and methodological experts from computer science, statistics, and applied mathematics. While many of these individuals rarely cross professional paths, BIDS actively seeks new and creative ways to engage and foster collaboration across these different research fields. In this presentation, I will share my own story, along with some insights into how BIDS is supporting the careers of data scientists, including graduate students, postdocs, faculty, and research staff. I will also describe how these individuals we are helping support are working to address a number of data science-related challenges in scientific research.

  11. 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...

  12. Collective instabilities and collisional effects for a 2D model of a beam in a storage ring

    CERN Document Server

    Benedetti, C

    2007-01-01

    We consider a collisional 2D model for a beam in a ring. In the smooth focusing approximation the relaxation time scales according to Landau’s theory, but the p.d.f of momentum jumps has a power law decaying queue. A new hybrid regime is found for the equipartitioning due to the interplay between collisional and collective effects. The moments equations of a small perturbation to the KV distribution are analytically determined and the stability conditions follow from Floquet’s theory.

  13. Optimizing the lattice design of a diffraction-limited storage ring with a rational combination of particle swarm and genetic algorithms

    Science.gov (United States)

    Jiao, Yi; Xu, Gang

    2017-02-01

    In the lattice design of a diffraction-limited storage ring (DLSR) consisting of compact multi-bend achromats (MBAs), it is challenging to simultaneously achieve an ultralow emittance and a satisfactory nonlinear performance, due to extremely large nonlinearities and limited tuning ranges of the element parameters. Nevertheless, in this paper we show that the potential of a DLSR design can be explored with a successive and iterative implementation of the multi-objective particle swarm optimization (MOPSO) and multi-objective genetic algorithm (MOGA). For the High Energy Photon Source, a planned kilometer-scale DLSR, optimizations indicate that it is feasible to attain a natural emittance of about 50 pm·rad, and simultaneously realize a sufficient ring acceptance for on-axis longitudinal injection, by using a hybrid MBA lattice. In particular, this study demonstrates that a rational combination of the MOPSO and MOGA is more effective than either of them alone, in approaching the true global optima of an explorative multi-objective problem with many optimizing variables and local optima. Supported by NSFC (11475202, 11405187) and Youth Innovation Promotion Association CAS (2015009)

  14. Optimizing the lattice design for a diffraction-limited storage ring with a rational combination of particle swarm and genetic algorithms

    CERN Document Server

    Jiao, Y

    2016-01-01

    In the design of a diffraction-limited storage ring (DLSR) consisting of compact multi-bend achromats (MBAs), it is challenging to simultaneously achieve an ultralow emittance and a satisfactory nonlinear performance, due to extremely large nonlinearities and limited tuning ranges of the element parameters. Nevertheless, taking the High Energy Photon Source (HEPS) as an example, we demonstrate that the potential of a DLSR design can be explored with a successive and iterative implementation of the particle swarm optimization (PSO) and multi-objective genetic algorithm (MOGA). It turns out that with a hybrid MBA lattice, it is feasible for the HEPS to attain a natural emittance of about 50 pm.rad, and meanwhile, realize a sufficient ring acceptance for beam accumulation with an on-axis longitudinal injection scheme. Particularly, this study indicates that a rational combination of the PSO and MOGA is more effective than either of them alone in approaching the true global optima, for an explorative multi-object...

  15. Parameter optimization for Doppler laser cooling of a low-energy heavy ion beam at the storage ring S-LSR

    Science.gov (United States)

    Osaki, Kazuya; Okamoto, Hiromi

    2014-05-01

    S-LSR is a compact ion storage ring constructed at Kyoto University several years ago. The ring is equipped with a Doppler laser cooling system aimed at beam crystallization. Bearing in mind hardware limitations in S-LSR, we try to find an optimum set of primary experimental parameters for the production of an ultracold heavy ion beam. Systematic molecular dynamics simulations are carried out for this purpose. It is concluded that the detuning and spot size of the cooling laser should be chosen around -42 MHz and 1.5 mm, respectively, for the most efficient cooling of 40 keV ^{24}Mg^+ beams in S-LSR. Under the optimum conditions, the use of the resonant coupling method followed by radio-frequency field ramping enables us to reach an extremely low beam temperature on the order of 0.1 K in the transverse degrees of freedom. The longitudinal degree of freedom can be cooled to close to the Doppler limit; i.e., to the mK range. We also numerically demonstrate that it is possible to establish a stable, long one-dimensionally ordered state of ions.

  16. The g-2 ring

    CERN Multimedia

    1974-01-01

    The precise measurement of "g-2", the anomalous magnetic moment of the muon, required a special muon storage ring with electrostatic focussing and very accurate knowledge of the magnetic bending field. For more details see under photo 7405430.

  17. 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...

  18. Injector for CESAR (2 MeV electron storage ring): 2-beam, 2 MV van de Graaff generator.

    CERN Document Server

    1963-01-01

    The van de Graaff generator in its tank. For voltage-holding, the tank was filled with pressurized extra-dry nitrogen. 2 beams emanated from 2 separate electron-guns. The left beam, for injection into the CESAR ring, was pulsed at 50 Hz, with currents of up to 1 A for 400 ns. The right beam was sent to a spectrometer line. Its pulselength was also 400 ns, but the pulse current was 12 microA, at a rate variable from 50 kHz to 1 MHz. This allowed stabilization of the top-terminal voltage to an unprecedented stability of +- 100 V, i.e. 6E-5. Although built for a nominal voltage of 2 MV, the operational voltage was limited to 1.75 MV in order to minimize voltage break-down events.

  19. The Berkeley gas-filled separator

    CERN Document Server

    Ninov, V; McGrath, C A

    1998-01-01

    The BGS is being constructed at the 88-Inch Cyclotron at LBNL in Berkeley. The magnetic configuration of the BGS will allow a large angular acceptance and good suppression of primary beam particles. BGS operates as a mass spectrometer with a A/ Delta A approximately =200 and as a gas filled separator at pressures between 0.1-50 hPa. The reaction products recoiling off a thin target will be collected with efficiencies from 10-80at the focal plane. A Monte Carlo simulation program of the ion transport through the gas-filled magnets in combination of 3-dimensional TOSCA field maps has been developed and reproduces closely the experimental behavior of BGS. (9 refs).

  20. Lawrence Berkeley Laboratory Affirmative Action Program. Revised

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The Lawrence Berkeley Laboratory`s Affirmative Action Program (AAP) serves as a working document that describes current policies, practices, and results in the area of affirmative action. It represents the Laboratory`s framework for an affirmative approach to increasing the representation of people of color and women in segments of our work force where they have been underrepresented and taking action to increase the employment of persons with disabilities and special disabled and Vietnam era veterans. The AAP describes the hierarchy of responsibility for Laboratory affirmative action, the mechanisms that exist for full Laboratory participation in the AAP, the policies and procedures governing recruitment at all levels, the Laboratory`s plan for monitoring, reporting, and evaluating affirmative action progress, and a description of special affirmative action programs and plans the Laboratory has used and will use in its efforts to increase the representation and retention of groups historically underrepresented in our work force.

  1. The Berkeley extreme ultraviolet calibration facility

    Science.gov (United States)

    Welsh, Barry Y.; Jelinsky, Patrick; Malina, Roger F.

    1988-01-01

    The vacuum calibration facilities of the Space Sciences Laboratory, University of California at Berkeley are designed for the calibration and testing of EUV and FUV spaceborne instrumentation (spectral range 44-2500 A). The facility includes one large cylindrical vacuum chamber (3 x 5 m) containing two EUV collimators, and it is equipped with a 4-axis manipulator of angular-control resolution 1 arcsec for payloads weighing up to 500 kg. In addition, two smaller cylindrical chambers, each 0.9 x 1.2 m, are available for vacuum and thermal testing of UV detectors, filters, and space electronics hardware. All three chambers open into class-10,000 clean rooms, and all calibrations are referred to NBS secondary standards.

  2. Telescience at the University of California, Berkeley

    Science.gov (United States)

    Chakrabarti, S.; Marchant, W. T.; Kaplan, G. C.; Dobson, C. A.; Jernigan, J. G.; Lampton, M. L.; Malina, R. F.

    1989-01-01

    The University of California at Berkeley (UCB) is a member of a university consortium involved in telescience testbed activities under the sponsorship of NASA. Our Telescience Testbed Project consists of three experiments using flight hardware being developed for the Extreme Ultraviolet Explorer project at UCB's Space Sciences Laboratory. The first one is a teleoperation experiment investigating remote instrument control using a computer network such as the Internet. The second experiment is an effort to develop a system for operation of a network of remote workstations allowing coordinated software development, evaluation, and use by widely dispersed groups. The final experiment concerns simulation as a method to facilitate the concurrent development of instrument hardware and support software. We describe our progress in these areas.

  3. The Berkeley SETI program - SERENDIP IV instrumentation

    Science.gov (United States)

    Werthimer, Dan; Bowyer, Stuart; Ng, David; Donnelly, Charles; Cobb, Jeff; Lampton, Michael; Airieau, Sabine

    1997-01-01

    We discuss the hardware design of SERENDIP IV, which will be deployed in early 1997 for a 21-cm sky survey at the National Astronomy and Ionospheric Center's 305-m radio telescope in Arecibo, Puerto Rico. SERENDIP IV is a 167 million channel spectrum analyzer, covering a 100-Mhz bandwidth, with 0.6-Hz resolution and a 1.7-s integration time. SERENDIP IV's modular design incorporates a bank of digital mixers and filters to separate the 100 MHz band into 40 2.5 MHz subbands. Each 2.5 MHz subband is further broken down into 0.6 Hz bins by means of a four million point fast Fourier transform. The resulting power spectra are analyzed by 40 high-speed processors. Narrowband signals having power significantly above background noise levels are recorded along with telescope coordinates, time, and frequency. The data are sent in real time to Berkeley for analysis.

  4. Junior High Schools of Berkeley, California. Bulletin, 1923, No. 4

    Science.gov (United States)

    Preston, James T.; Clark, W. B.; Glessner, H. H.; Hennessey, D. L.

    1923-01-01

    This bulletin demonstrates that Berkeley, California's educational problem is and has been that of meeting the varied needs of a population such as may be found in any typical American city. The varied population needs, together with the rapid growth, have brought many difficult problems to Berkeley, just has they have to other cities. Based on…

  5. The Fermilab recycler ring

    Energy Technology Data Exchange (ETDEWEB)

    Martin Hu

    2001-07-24

    The Fermilab Recycler is a permanent magnet storage ring for the accumulation of antiprotons from the Antiproton Source, and the recovery and cooling of the antiprotons remaining at the end of a Tevatron store. It is an integral part of the Fermilab III luminosity upgrade. The following paper describes the design features, operational and commissioning status of the Recycler Ring.

  6. Injector for CESAR (2 MeV electron storage ring): 2-beam, 2 MV van de Graaff generator; tank removed.

    CERN Multimedia

    1968-01-01

    The van de Graaff generator in its tank. For voltage-holding, the tank was filled with pressurized extra-dry nitrogen. 2 beams emanated from 2 separate electron-guns. The left beam, for injection into the CESAR ring, was pulsed at 50 Hz, with currents of up to 1 A for 400 ns. The right beam was sent to a spectrometer line. Its pulselength was also 400 ns, but the pulse current was 12 microA, at a rate variable from 50 kHz to 1 MHz. This allowed stabilization of the top-terminal voltage to an unprecedented stability of +- 100 V, i.e. 6E-5. Although built for a nominal voltage of 2 MV, the operational voltage was limited to 1.75 MV in order to minimize voltage break-down events. CESAR was terminated at the end of 1967 and dismantled in 1968. R.Nettleton (left) and H.Burridge (right) are preparing the van de Graaff for shipment to the University of Swansea.

  7. What Made Berkeley Great? The Sources of Berkeley's Sustained Academic Excellence. Research & Occasional Paper Series CSHE.3.11

    Science.gov (United States)

    Breslauer, George W.

    2011-01-01

    University of California (UC) Berkeley's chief academic officer explores the historical sources of Berkeley' academic excellence. He identifies five key factors: (1) wealth from many sources; (2) supportive and skilled governors; (3) leadership from key UC presidents; (4) the pioneering ethos within the State of California; and (5) a process of…

  8. Radioactive ion beam development in Berkeley

    CERN Document Server

    Wutte, D C; Leitner, M A; Xie, Z Q

    1999-01-01

    Two radioactive ion beam projects are under development at the 88" Cyclotron, BEARS (Berkeley Experiment with accelerated radioactive species) and the 14O experiment. The projects are initially focused on the production of 11C and 14O, but it is planned to expand the program to 17F, 18F, 13N and 76Kr. For the BEARS project, the radioactivity is produced in form of either CO2 or N2O in a small medical 10 MeV proton cyclotron. The activity is then transported through a 300 m long He-jet line to the 88" cyclotron building, injected into the AECR-U ion source and accelerated through the 88" cyclotron to energies between 1 to 30 MeV/ nucleon. The 14O experiment is a new experiment at the 88" cyclotron to measure the energy-shape of the beta decay spectrum. For this purpose, a target transfer line and a radioactive ion beam test stand has been constructed. The radioactivity is produced in form of CO in a hot carbon target with a 20 MeV 3He from the 88" Cyclotron. The activity diffuses through an 8m long stainless s...

  9. Life sciences: Lawrence Berkeley Laboratory, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    Life Sciences Research at LBL has both a long history and a new visibility. The physics technologies pioneered in the days of Ernest O. Lawrence found almost immediate application in the medical research conducted by Ernest's brother, John Lawrence. And the tradition of nuclear medicine continues today, largely uninterrupted for more than 50 years. Until recently, though, life sciences research has been a secondary force at the Lawrence Berkeley Laboratory (LBL). Today, a true multi-program laboratory has emerged, in which the life sciences participate as a full partner. The LBL Human Genome Center is a contribution to the growing international effort to map the human genome. Its achievements represent LBL divisions, including Engineering, Materials and Chemical Sciences, and Information and Computing Sciences, along with Cell and Molecular Biology and Chemical Biodynamics. The Advanced Light Source Life Sciences Center will comprise not only beamlines and experimental end stations, but also supporting laboratories and office space for scientists from across the US. This effort reflects a confluence of scientific disciplines --- this time represented by individuals from the life sciences divisions and by engineers and physicists associated with the Advanced Light Source project. And finally, this report itself, the first summarizing the efforts of all four life sciences divisions, suggests a new spirit of cooperation. 30 figs.

  10. Measurement of proton-proton and proton-antiproton elastic scattering at the European center for nuclear research intersecting storage rings

    CERN Document Server

    Amos, Norman A

    1985-01-01

    Proton-proton and proton-antiproton elastic scattering was measured at the CERN Intersecting Storage Rings. Using the optical theorem, we have extracted the total nuclear cross sections for these collisions. By measuring the interference between the Coulomb amplitude and the nuclear amplitude we have found rho, the ratio of the real part to the imaginary part of the forward nuclear elastic scattering amplitude. Further, we have extracted the nuclear slope parameter in the forward direction. For proton-proton interactions, the total nuclear cross sections measured were 39.95 +- 0.30 mb and 42.19 +- 0.19 mb for center-of-mass energies √s = 30.6 GeV and 52.8 GeV, respectively. The measured values of rho were 0.035 +- 0.009 and 0.071 +- 0.010. For proton-antiproton interactions, the cross sections found were 41.10 +- 0.40 mb and 43.34 +- 0.43 mb, respectively, and the rho values were 0.088 +- 0.025 and 0.066 +- 0.022

  11. Single differential projectile ionization cross sections d σ/dEe for 50 AMeV U28+ in the ESR storage ring

    Science.gov (United States)

    Hagmann, Siegbert; Hillenbrand, Pierre-Michel; Stoehlker, Thomas; Litvinov, Yuri; Appa-Sparc Collaboration

    2013-05-01

    The very high intensity beams of relativistic high Z ions with incident collision energies up to 2.7AGeV requested for experiments using the SIS100 synchrotron of FAIR require that 1.3 1011 ions at 2.6Hz be injected from SIS12/18 into SIS100. The needed luminosity of the beam can only be achieved for such high Z ions when - considering the space charge limit (~A/q2) - a low charge state q of the ion to be accelerated keeps the particle density at the highest feasible level. For a thorough understanding of beam loss it is imperative that the mechanisms active in projectile ionization be understood quantitatively to provide benchmarks for advancedab initio theories beyond first order. We have embarked on an experimental investigation of single differential projectile ionization cross sections d σ/dEe (SDCS) for single and multiple ionization of U28+in the ESR storage ring by measuring the electron loss to continuum (ELC) cusp at 00 with respect to the beam axis employing our imaging forward electron spectrometer. This was motivated by the high relative fraction of multiple ionization estimated to exceed 40%. We report first results for absolute projectile ionization SDCS for U28+. We find a remarkably high asymmetry for the ELC cusp. This is at strong variance with the line shape expected for validity of first order theories.

  12. 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...

  13. Energy and Resources Group, University of California, Berkeley.

    Science.gov (United States)

    Christensen, Mark N.

    1987-01-01

    Describes an interdisciplinary program at the University of California (Berkeley) that addresses the multifaceted problems of energy and resources through a teaching and resource program. Discusses the program's structure, curriculum, research activities, students, resources, and problems and possibilities. (TW)

  14. Former Fermilab boss to lead Lawrence Berkeley National Laboratory

    Science.gov (United States)

    Gwynne, Peter

    2016-03-01

    Particle physicist Michael Witherell - current vice-chancellor for research at the University of California, Santa Barbara (UCSB) - has been appointed the next director of the Lawrence Berkeley National Laboratory (LBL).

  15. Annual environmental monitoring report of the Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Schleimer, G.E.; Pauer, R.O. (eds.)

    1990-08-01

    The Lawrence Berkeley Laboratory (LBL) is a multiprogram national laboratory managed by the University of California (UC) for the US Department of Energy (DOE). LBL's major role is to conduct basic and applied science research that is appropriate for an energy research laboratory. The Environmental Monitoring Program of the Lawrence Berkeley Laboratory is described. Data for 1989 are presented, and general trends are discussed. 17 refs., 12 figs., 23 tabs.

  16. ALS Booster Ring RF System Upgrade for Top-Off Mode of Operation

    CERN Document Server

    Kwiatkowski, Slawomir

    2005-01-01

    ALS is one of the first third generation synchrotron light sources which has been operating since 1993 at Berkeley Lab. In the present ALS operation scenario 1.5GeV electron beam is injected from the booster into the storage ring every 8 hours where is accelerated to the final energy of 1.9GeV. The beam decays between fills from 400mA to 200mA with the time average current of 250mA. In order to increase the beam brighthess ALS team plans to increase the beam current to 500mA and maintain it constant during machine operation ("Top-Off" mode of operation). This operation scenario will require full energy injection from the booster ring into the storage ring and constant operation of the injector (10 bunches with the total charge of 1nC every 30 to 35 seconds). In this paper we will present the results of the ALS injector RF system analysis fo Top-Off mode of operation and describe the way we intent to implement the necessary modifications to the booster RF system.

  17. 上海光源储存环束流轨道联锁系统升级%Storage ring beam orbit interlock system upgrade for SSRF

    Institute of Scientific and Technical Information of China (English)

    耿合龙; 冷用斌; 周伟民; 赖龙伟; 沈通; 阎映炳

    2015-01-01

    Background: Required by machine malfunction analysis, the beam orbit interlock system for the storage ring needs to be upgraded at the Shanghai Synchrotron Radiation Facility (SSRF). Purpose: This study aims to implement an upgraded new interlock system that can label 140 interlock signals coming from different Beam Position Monitor (BPM) electronics and record all data in the new system. And the turn-by-turn data in the BPM electronics Post Mortem buffer will be latched whenever the interlock occurs. Methods: The interlock signals and the latch signals were transmitted through the optical fiber and processed in an NI PXI 7813R Field Programmable Gate Array (FPGA) board. NI PXI-8106 controller is configured to run Linux operation system for Input/Output Controller (IOC) of Experimental Physics and Industrial Control System (EPICS) and communicate with PXI 7813R board which processes all interlock signals. Results: All interlock signal processing and latched trigger signal output were achieved in the FPGA board. The new system was fully integrated to the main EPICS for the storage ring. And the system runs as expected. Conclusions: The online test data show that the new system can detect the first interlock signal caused by the machine abnormality while the turn-by-turn data are latched. The analysis of turn-by-turn data shows the first BPM electronics which sends the interlock signal. The result is consistent with the FPGA board. Meanwhile, beam orbit changes were observed during beam abortions.%针对上海光源机器故障分析的需求,对原有储存环束流轨道联锁系统进行升级,实现对储存环束流位置测量系统中140台束流位置监测器(Beam Position Monitor, BPM)电子学输出的联锁信号进行标记,同时锁存丟束过程中所有BPM电子学中的逐圈轨道数据。联锁信号的处理与锁存触发信号的输出在FPGA (Field Programmable Gate Array)内完成。该系统集成至储存环的物理

  18. A novel Beam-Down System for Solar Power Generation with Multi-Ring Central Reflectors and Molten Salt Thermal Storage

    Energy Technology Data Exchange (ETDEWEB)

    Tamaura, Y.; Utamura, M.; Kaneko, H.; Hasuike, H.; Domingo, M.; Relloso, S.

    2006-07-01

    A new concept of beam-down solar power with thermal storage is proposed. The system is featured in an optical system with multi-ring central reflectors and a liquid film molten salt thermal receiver installed near ground level. Its feasibility study has been carried out and power generation cost as well as EPC cost has been estimated. To compensate the drawback to a beam-down solar concentrating system in optical losses, a new receiver concept of liquid film molten salt thermal receiver is designed to aim at higher thermal efficiency than that of tubular receiver. Molten salt liquid film is formed along the inner surface of the receiver wall. The liquid film flows down by gravity. It is shown that the liquid film receiver has a high heat exchange potential up to 2MW/m2 of solar beam flux on the inner wall surface and proved to be feasible. Assuming 24 hour continuous power generation located at Almeria Spain, conceptual designs for two capacities of 120MWt (commercial plant) and 20MWt (pilot plant) have been made. The height and the radius of the central receiver have been optimized as a result of trade off of optical loss and the cost of the central reflector and its support structure. The total cost of the Beam-Down will become 8.37 US cents/kWh, which will be competitive with coal and natural gas, when crude oil cost increases. TITECH (Tokyo Institute of Technology) plans to launch an international program to develop the innovative/cheaper solar tower beam--down concentrating system. (Author)

  19. A first course in noncommutative rings

    CERN Document Server

    Lam, T Y

    2001-01-01

    A First Course in Noncommutative Rings, an outgrowth of the author's lectures at the University of California at Berkeley, is intended as a textbook for a one-semester course in basic ring theory. The material covered includes the Wedderburn-Artin theory of semisimple rings, Jacobson's theory of the radical, representation theory of groups and algebras, prime and semiprime rings, local and semilocal rings, perfect and semiperfect rings, etc. By aiming the level of writing at the novice rather than the connoisseur and by stressing th the role of examples and motivation, the author has produced a text that is suitable not only for use in a graduate course, but also for self- study in the subject by interested graduate students. More than 400 exercises testing the understanding of the general theory in the text are included in this new edition.

  20. 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.

  1. Berkeley Phylogenomics Group web servers: resources for structural phylogenomic analysis.

    Science.gov (United States)

    Glanville, Jake Gunn; Kirshner, Dan; Krishnamurthy, Nandini; Sjölander, Kimmen

    2007-07-01

    Phylogenomic analysis addresses the limitations of function prediction based on annotation transfer, and has been shown to enable the highest accuracy in prediction of protein molecular function. The Berkeley Phylogenomics Group provides a series of web servers for phylogenomic analysis: classification of sequences to pre-computed families and subfamilies using the PhyloFacts Phylogenomic Encyclopedia, FlowerPower clustering of proteins sharing the same domain architecture, MUSCLE multiple sequence alignment, SATCHMO simultaneous alignment and tree construction and SCI-PHY subfamily identification. The PhyloBuilder web server provides an integrated phylogenomic pipeline starting with a user-supplied protein sequence, proceeding to homolog identification, multiple alignment, phylogenetic tree construction, subfamily identification and structure prediction. The Berkeley Phylogenomics Group resources are available at http://phylogenomics.berkeley.edu.

  2. Near IR photometry of the old open clusters Berkeley 17 and Berkeley 18 Probing the age of the galactic disc

    CERN Document Server

    Carraro, G; Girardi, L; Richichi, A; Carraro, Giovanni; Vallenari, Antonella; Girardi, Leo; Richichi, Andrea

    1998-01-01

    We report on near IR ($J$ and $K$ bands) observations of two $8 \\times 8 Berkeley~18, for which only optical photometry (in $B$,$V$ and $I$ bands) exists. $J$ and $K$ photometry allows us to obtain an independent estimate of cluster metallicity by means of the relationship between the spectroscopic metallicity and the Red Giant Branch (RGB) slope calibrated by Tiede et al (1997). From the analysis of the colour magnitude diagram (CMD) and luminosity function (LF), Berkeley~17 turns out to have a metal content $[Fe/H]~\\sim~-0.35$. It is $9~Gyr$ old, suffers from a reddening $E(B-V) = 0.58 mag$ and has an heliocentric distance of $2.5 kpc$. Berkeley~17 comes out to be substantially younger than in previous work (age $\\approx 13~Gyr$). On the other hand Berkeley~18 is found to have solar metal abundance, and to be younger than Berkeley~17, with an age of about $4~Gyr$. While we confirm Kaluzny (1997) reddening estimate, we significantly revise the distance of the cluster, which lies $4.5 kpc$ from the Sun. These...

  3. Laser system for cooling of relativistic C{sup 3+}-ion beams in storage rings; Lasersystem zur Kuehlung relativistischer C{sup 3+}-Ionenstrahlen in Speicherringen

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Tobias

    2015-02-15

    Cold ion beams are essential for many precision experiments at storage rings. While spectroscopic experiments gain from the high energy resolution, collision experiments benefit from the increased luminosity. Furthermore, sympathetic cooling of exotic species is conceivable with the aid of cold ion beams. Besides the long established electron cooling, alternative cooling methods are gaining in importance, especially for high energy particles. In the past, experiments to cool ions with lasers were performed. Because of the matching wavelength and output power, frequency doubled Argon-ion lasers at 257 nm were used during these experiments. Due to the strongly limited scanning potential of these systems, it was not possible to cool the full inertia spread of the ion beams. A new laser system was developed in this thesis because of the lack of commercial alternatives. After the characterization of the system, it was tested during a beamtime at the Experimentierspeicherring (ESR) at the Gesellschaft fuer Schwerionenforschung (GSI). The completely solid state based system delivers up to 180 mW of output power at 257 nm and is modehop free tunable up to 16 GHz in 10 ms at this wavelength. By using efficient diode lasers, the new system consumes considerably less power than comparable Argon-ion lasers. The fundamental wavelength of 1028 nm is amplified up to 16 W with an Yb-doped fiber amplifier. Subsequently, the target wavelength of 257 nm is realized in two consecutive build-up cavities. Another diode laser, stabilized to a wavelength meter, serves as a frequency reference. This new laser system first came to operation during beamtime in August 2012, when relativistic C{sup 3+} ions with β=0.47 were cooled successfully. For the first time it was possible to access the whole inertia spread of a bunched ion beam without electron precooling. In contrast to prior experiments, only the laser frequency was scanned and not the bunching frequency of the ion beam. The results

  4. Lawrence Berkeley Laboratory Institutional Plan FY 1987-1992

    Energy Technology Data Exchange (ETDEWEB)

    Various

    1986-12-01

    The Lawrence Berkeley Laboratory, operated by the University of California for the Department of Energy, provides national scientific leadership and supports technological innovation through its mission to: (1) Perform leading multidisciplinary research in general sciences and energy sciences; (2) Develop and operate unique national experimental facilities for use by qualified investigators; (3) Educate and train future generations of scientists and engineers; and (4) Foster productive relationships between LBL research programs and industry. The following areas of research excellence implement this mission and provide current focus for achieving DOE goals. GENERAL SCIENCES--(1) Accelerator and Fusion Research--accelerator design and operation, advanced accelerator technology development, accelerator and ion source research for heavy-ion fusion and magnetic fusion, and x-ray optics; (2) Nuclear Science--relativistic heavy-ion physics, medium- and low-energy nuclear physics, nuclear theory, nuclear astrophysics, nuclear chemistry, transuranium elements studies, nuclear data evaluation, and detector development; (3) Physics--experimental and theoretical particle physics, detector development, astrophysics, and applied mathematics. ENERGY SCIENCES--(1) Applied Science--building energy efficiency, solar for building systems, fossil energy conversion, energy storage, and atmospheric effects of combustion; (2) Biology and Medicine--molecular and cellular biology, diagnostic imaging, radiation biophysics, therapy and radiosurgery, mutagenesis and carcinogenesis, lipoproteins, cardiovascular disease, and hemopoiesis research; (3) Center for Advanced Materials--catalysts, electronic materials, ceramic and metal interfaces, polymer research, instrumentation, and metallic alloys; (4) Chemical Biodynamics--molecular biology of nucleic acids and proteins, genetics of photosynthesis, and photochemistry; (5) Earth Sciences--continental lithosphere properties, structures and

  5. Technology Being Developed at Lawrence Berkeley National Laboratory: Ultra-Low- Emission Combustion Technologies for Heat and Power Generation

    Science.gov (United States)

    Cheng, Robert K.

    2001-01-01

    The Combustion Technologies Group at Lawrence Berkeley National Laboratory has developed simple, low-cost, yet robust combustion technologies that may change the fundamental design concept of burners for boilers and furnaces, and injectors for gas turbine combustors. The new technologies utilize lean premixed combustion and could bring about significant pollution reductions from commercial and industrial combustion processes and may also improve efficiency. The technologies are spinoffs of two fundamental research projects: An inner-ring burner insert for lean flame stabilization developed for NASA- sponsored reduced-gravity combustion experiments. A low-swirl burner developed for Department of Energy Basic Energy Sciences research on turbulent combustion.

  6. Cobalt hydroxide/oxide hexagonal ring-graphene hybrids through chemical etching of metal hydroxide platelets by graphene oxide: energy storage applications.

    Science.gov (United States)

    Nethravathi, C; Rajamathi, Catherine R; Rajamathi, Michael; Wang, Xi; Gautam, Ujjal K; Golberg, Dmitri; Bando, Yoshio

    2014-03-25

    The reaction of β-Co(OH)2 hexagonal platelets with graphite oxide in an aqueous colloidal dispersion results in the formation of β-Co(OH)2 hexagonal rings anchored to graphene oxide layers. The interaction between the basic hydroxide layers and the acidic groups on graphene oxide induces chemical etching of the hexagonal platelets, forming β-Co(OH)2 hexagonal rings. On heating in air or N2, the hydroxide hybrid is morphotactically converted to porous Co3O4/CoO hexagonal ring-graphene hybrids. Porous NiCo2O4 hexagonal ring-graphene hybrid is also obtained through a similar process starting from β-Ni0.33Co0.67(OH)2 platelets. As electrode materials for supercapacitors or lithium-ion batteries, these materials exhibit a large capacity, high rate capability, and excellent cycling stability.

  7. Lawrence Berkeley Laboratory Institutional Plan FY 1995--2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-01

    This report presents the details of the mission and strategic plan for Lawrence Berkeley Laboratory during the fiscal years of 1995--2000. It presents summaries of current programs and potential changes; critical success factors such as human resources; management practices; budgetary allowances; and technical and administrative initiatives.

  8. UC-Berkeley-area citizens decry waste transfer from lab.

    CERN Multimedia

    Nakasato, L

    2002-01-01

    Residents are working to stop the transfer of potentially hazardous and radioactive material from Lawrence Berkeley National Laboratory. The lab has begun to dismantle the Bevatron which has been shut down since 1993 and says eight trucks per day will move material offsite (1 page).

  9. Teaching at Berkeley: A Guide for Foreign Teaching Assistants.

    Science.gov (United States)

    Cohen, Robby, Ed.; Robin, Ron, Ed.

    A handbook for foreign teaching assistants (TAs) is presented by foreign graduate students with teaching experience and other educators who have worked closely with them. Language skills, teaching strategies, cultural issues, resources, and the environment at the University of California, Berkeley, are addressed in 16 articles. Article titles and…

  10. For Berkeley's Sports Endowment, a Goal of $1-Billion

    Science.gov (United States)

    Keller, Josh

    2009-01-01

    Most athletics programs, if forced to raise $300-million to renovate a football stadium, would not set an ambitious endowment goal at the same time. The University of California at Berkeley is trying to do both. The university's California Memorial Stadium sits directly over an earthquake fault: it needs a major seismic retrofit that will take…

  11. Berkeley extreme-ultraviolet airglow rocket spectrometer - BEARS

    Science.gov (United States)

    Cotton, D. M.; Chakrabarti, S.

    1992-01-01

    The Berkeley EUV airglow rocket spectrometer (BEARS) instrument is described. The instrument was designed in particular to measure the dominant lines of atomic oxygen in the FUV and EUV dayglow at 1356, 1304, 1027, and 989 A, which is the ultimate source of airglow emissions. The optical and mechanical design of the instrument, the detector, electronics, calibration, flight operations, and results are examined.

  12. Integration Defended: Berkeley Unified's Strategy to Maintain School Diversity

    Science.gov (United States)

    Chavez, Lisa; Frankenberg, Erica

    2009-01-01

    In June 2007, the Supreme Court limited the tools that school districts could use to voluntarily integrate schools. In the aftermath of the decision, educators around the country have sought models of successful plans that would also be legal. One such model may be Berkeley Unified School District's (BUSD) plan. Earlier this year, the California…

  13. Ring blowers. Ring blower

    Energy Technology Data Exchange (ETDEWEB)

    Nakahara, Y.; Okamura, T.; Takahashi, M. (Fuji Electric Co. Ltd., Tokyo (Japan))

    1991-06-10

    Features, structures and several products of ring blowers were outlined. The ring blower is featured by its medium characteristics because it is higher in air pressure than a turboblower and larger in airflow than a vane blower, and it is applicable flexibly to not only air blasting but various industrial fields such as suction transfer. As several products corresponding to various fields, the followings were outlined: the low noise type with optimum shapes of inlet, outlet and casing cover for reducing noises by 10 dB or more, the heat resistant, water-tight and explosion-proof types suitable for severe environmental conditions, the multi-voltage type for every country served at different voltages, the high air pressure type with two pressure rise stages, and the large airflow type with a wide impeller. In addition, as special use products, the glass fiber reinforced unsatulated polyester ring blower for respiration apparatus, and the variable speed blushless DC motor-driven one for medical beds were outlined. 2 refs., 9 figs., 1 tab.

  14. The Undergraduate Origins of PhD Economists: The Berkeley Experience

    Science.gov (United States)

    Olney, Martha L.

    2015-01-01

    The University of California, Berkeley sends more undergraduate students to economics PhD programs than any other public university. While this fact is surely a function of its size, there may be lessons from the Berkeley experience that others could adopt. To investigate why Berkeley generates so many economics PhD students, the author convened…

  15. 碎石环梁与混凝土环梁超大储罐强夯地基沉降变形对比研究%NUMERICAL COMPARISONS OF SEDIMENTATION CHARACTERISTICS FOR STORAGE TANKS FOUNDATIONS WITH GRAVEL RING WALL OR CONCRETE RING WALL

    Institute of Scientific and Technical Information of China (English)

    李洪江; 刘红军; 黄永勃; 张浩; 吉成林

    2015-01-01

    地层沉降及不均匀沉降控制是储罐建造安全性保障的重要环节。本文重点分析了加设碎石环梁强夯地层的沉降变形特征,综合比较了碎石环梁与混凝土环梁加固储罐地基土的环向、径向沉降与不均匀沉降差异;指出地层差异能影响两类环梁基础的地基土加固效果;考察了碎石环梁弹性模量改变对储罐地基土沉降规律的影响;比较了截面为矩形的混凝土环梁与梯形碎石环梁对储罐地层的加固效果;并给出了碎石环梁加固储罐地基土的工程建议。研究成果可为类似工程建设提供借鉴参考。%Ground settlement and uneven settlement control is an important part of the tank construction safety. This paper analyzes the settlement deformation characteristics of tanks foundation added gravel ring wall in detail. The settlement and uneven settlement differences are compared for storage tank foundations added with gravel ring wall or concrete ring wall along both ring and radial directions.The relationships between elastic modulus of gravel ring wall and foundation settlement rules are analyzed.The different reinforcement effects of rectangular concrete ring walls and trapezoidal gravel ring walls are compared.Engineering suggestions of gravel ring walls used to reinforce the tank foundation are given in the final.The research results can have a great significance to similar engineering projects.

  16. Vortex rings

    Energy Technology Data Exchange (ETDEWEB)

    Akhmetov, D.G. [Lavrentiev Institute of Hydrodynamics, Novosibirsk (Russian Federation)

    2009-07-01

    This book presents a comprehensive coverage of the wide field of vortex rings. The book presents the results of systematic experimental investigations, theoretical foundation, as well as the practical applications of vortex rings, such as the extinction of fires at gushing gas and oil wells. All the basic properties of vortex rings as well as their hydrodynamic structures are presented. Special attention is paid to the formation and motion of turbulent vortex rings. (orig.)

  17. Catalog of research projects at Lawrence Berkeley Laboratory, 1985

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This Catalog has been created to aid in the transfer of technology from the Lawrence Berkeley Laboratory to potential users in industry, government, universities, and the public. The projects are listed for the following LBL groups: Accelerator and Fusion Research Division, Applied Science Division, Biology and Medicine Division, Center for Advanced Materials, Chemical Biodynamics Division, Computing Division, Earth Sciences Division, Engineering and Technical Services Division, Materials and Molecular Research Division, Nuclear Science Division, and Physics Division.

  18. Guide to user facilities at the Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1984-04-01

    Lawrence Berkeley Laboratories' user facilities are described. Specific facilities include: the National Center for Electron Microscopy; the Bevalac; the SuperHILAC; the Neutral Beam Engineering Test Facility; the National Tritium Labeling Facility; the 88 inch Cyclotron; the Heavy Charged-Particle Treatment Facility; the 2.5 MeV Van de Graaff; the Sky Simulator; the Center for Computational Seismology; and the Low Background Counting Facility. (GHT)

  19. Ring theory

    CERN Document Server

    Rowen, Louis H

    1991-01-01

    This is an abridged edition of the author's previous two-volume work, Ring Theory, which concentrates on essential material for a general ring theory course while ommitting much of the material intended for ring theory specialists. It has been praised by reviewers:**""As a textbook for graduate students, Ring Theory joins the best....The experts will find several attractive and pleasant features in Ring Theory. The most noteworthy is the inclusion, usually in supplements and appendices, of many useful constructions which are hard to locate outside of the original sources....The audience of non

  20. Evaluating the Impact of Open Access at Berkeley: Results from the 2015 Survey of Berkeley Research Impact Initiative (BRII) Funding Recipients

    Science.gov (United States)

    Teplitzky, Samantha; Phillips, Margaret

    2016-01-01

    The Berkeley Research Impact Initiative (BRII) was one of the first campus-based open access (OA) funds to be established in North America and one of the most active, distributing more than $244,000 to support University of California (UC) Berkeley authors. In April 2015, we conducted a qualitative study of 138 individuals who had received BRII…

  1. Planetary Rings

    CERN Document Server

    Tiscareno, Matthew S

    2011-01-01

    Planetary rings are the only nearby astrophysical disks, and the only disks that have been investigated by spacecraft. Although there are significant differences between rings and other disks, chiefly the large planet/ring mass ratio that greatly enhances the flatness of rings (aspect ratios as small as 1e-7), understanding of disks in general can be enhanced by understanding the dynamical processes observed at close-range and in real-time in planetary rings. We review the known ring systems of the four giant planets, as well as the prospects for ring systems yet to be discovered. We then review planetary rings by type. The main rings of Saturn comprise our system's only dense broad disk and host many phenomena of general application to disks including spiral waves, gap formation, self-gravity wakes, viscous overstability and normal modes, impact clouds, and orbital evolution of embedded moons. Dense narrow rings are the primary natural laboratory for understanding shepherding and self-stability. Narrow dusty...

  2. Summary of the AccNet-EuCARD Workshop on Optics Measurements, Corrections and Modelling for High-Performance Storage Rings “OMCM”, CERN, Geneva, 20-22 June 2011

    CERN Document Server

    Bartolini, R; Calaga, R; Einfeld, D; Giovannozzi, M; Koutchouk, J-P; Milardi, C; Safranek, J; Tomás, R; Wenninger, J; Zimmermann, F

    2012-01-01

    The LHC, its luminosity upgrade HL-LHC, its injectors upgrade LIU and other high performance storage rings around the world are facing challenging requirements for optics measurements, correction and modelling. This workshop aims to do a review of the existing techniques to measure and control linear and non-linear optics parameters. The precise optics determination has proven to be a key ingredient to improve the performance of the past and present accelerators. From 20 to 22 June 2011 an international workshop, “OMCM,” was held at CERN with the goal of assessing the limits of the present techniques and evaluating new paths for improvement. The OMCM workshop was sponsored and supported by CERN and by the European Commission under the FP7 “Research Infrastructures” project EuCARD, grant agreement no. 227579.

  3. Community Relations Plan for Lawrence Berkeley Laboratory. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    The Lawrence Berkeley Laboratory (LBL) has applied to the California Environmental Protection Agency, Department of Toxic Substances Control (DTSC), for renewal of its Hazardous Waste Handling Facility Permit. A permit is required under Resource Conservation and Recovery Act (RCRA) regulations. The permit will allow LBL to continue using its current hazardous waste handling facility, upgrade the existing facility, and construct a replacement facility. The new facility is scheduled for completion in 1995. The existing facility will be closed under RCRA guidelines by 1996. As part of the permitting process, LBL is required to investigate areas of soil and groundwater contamination at its main site in the Berkeley Hills. The investigations are being conducted by LBL`s Environmental Restoration Program and are overseen by a number of regulatory agencies. The regulatory agencies working with LBL include the California Environmental Protection Agency`s Department of Toxic Substances Control, the California Regional Water Quality Control Board, the Bay Area Air Quality Management District, the East Bay Municipal Utilities District, and the Berkeley Department of Environmental Health. RCRA requires that the public be informed of LBL`s investigations and site cleanup, and that opportunities be available for the public to participate in making decisions about how LBL will address contamination issues. LBL has prepared this Community Relations Plan (CRP) to describe activities that LBL will use to keep the community informed of environmental restoration progress and to provide for an open dialogue with the public on issues of importance. The CRP documents the community`s current concerns about LBL`s Environmental Restoration Program. Interviews conducted between February and April 1993 with elected officials, agency staff, environmental organizations, businesses, site neighbors, and LBL employees form the basis for the information contained in this document.

  4. Lawrence Berkeley National Laboratory 1995 site environmental report

    Energy Technology Data Exchange (ETDEWEB)

    Balgobin, D.; Javandel, I.; Lackner, G.; Smith, C.; Thorson, P.; Tran, H.

    1996-07-01

    The 1995 Site Environmental Report summarizes environmental activities at the Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) for the 1995 calendar year. The report strives to present environmental data in a manner that characterizes the performance and compliance status of the environmental management programs. The report also discusses significant highlights and plans of these programs. Topics discussed include: environmental monitoring, environmental compliance programs, air quality, water quality, ground water protection, sanitary sewer monitoring, soil and sediment quality, vegetation and foodstuffs monitoring, and special studies which include preoperational monitoring of building 85 and 1995 sampling results, radiological dose assessment, and quality assessment.

  5. Stability of the Zagreb Carnegie-Mellon-Berkeley model

    CERN Document Server

    Osmanović, H; Švarc, A; Hadžimehmedović, M; Stahov, J

    2011-01-01

    In ref. [1] we have used the Zagreb realization of Carnegie-Melon-Berkeley coupled-channel, unitary model as a tool for extracting pole positions from the world collection of partial wave data, with the aim of eliminating model dependence in pole-search procedures. In order that the method is sensible, we in this paper discuss the stability of the method with respect to the strong variation of different model ingredients. We show that the Zagreb CMB procedure is very stable with strong variation of the model assumptions, and that it can reliably predict the pole positions of the fitted partial wave amplitudes.

  6. Assembly Manual for the Berkeley Lab Cosmic Ray Detector

    CERN Document Server

    Collier, M

    2002-01-01

    The Berkeley Lab Cosmic Ray Detector consists of 3 main components that must be prepared separately before they can be assembled. These components are the scintillator, circuit board, and casing. They are described in the main sections of this report, which may be completed in any order. Preparing the scintillator paddles involves several steps--cutting the scintillator material to the appropriate size and shape, preparing and attaching Lucite cookies (optional), polishing the edges, gluing the end to the photomultiplier tube (optional), and wrapping the scintillator. Since the detector has 2 paddles, each of the sections needs to be repeated for the other paddle.

  7. Assembly Manual for the Berkeley Lab Cosmic Ray Detector

    Energy Technology Data Exchange (ETDEWEB)

    Collier, Michael

    2002-12-17

    The Berkeley Lab Cosmic Ray Detector consists of 3 main components that must be prepared separately before they can be assembled. These components are the scintillator, circuit board, and casing. They are described in the main sections of this report, which may be completed in any order. Preparing the scintillator paddles involves several steps--cutting the scintillator material to the appropriate size and shape, preparing and attaching Lucite cookies (optional), polishing the edges, gluing the end to the photomultiplier tube (optional), and wrapping the scintillator. Since the detector has 2 paddles, each of the sections needs to be repeated for the other paddle.

  8. Lipoprotein subclasses in genetic studies: The Berkeley Data Set

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, R.M.; Williams, P.T.; Blanche, P.J.; Cavanaugh, A.; Holl, L.G. [Lawrence Berkeley Lab., CA (United States); Austin, M.A. [Washington Univ., Seattle, WA (United States). Dept. of Epidemiology

    1992-10-01

    Data from the Berkeley Data Set was used to investigate familial correlations of HDL-subclasses. Analysis of the sibling intraclass correlation coefficient by HDL particle diameter showed that sibling HDL levels were significantly correlated for HDL{sub 2b}, HDL{sub 3a} and HDL{sub 3b} subclasses. The percentage of the offsprings` variance explained by their two parents. Our finding that parents and offspring-have the highest correlation for HDL{sub 2b} is consistent with published reports that show higher heritability estimates for HDL{sub 2} compared with HDL{sub 3}{minus} cholesterol.

  9. USING DOE-2.1 AT LAWRENCE BERKELEY LABORATORY

    Energy Technology Data Exchange (ETDEWEB)

    Building Energy Analysis Group.; Authors, Various

    1980-09-01

    The purpose of this manual is to assist the DOE-2 user to run DOE-2 and its utility programs at Lawrence Berkeley Laboratory (LBL). It is organized to reflect the facts that every DOE-2 job run at LBL requires certain steps, and that there are options related to DOE-2 job runs available to any DOE-2 user. The standard steps for running a DOE-2 job are as follows: 1. Prepare a job deck 2. Process a job deck 3. Obtain standard output reports.

  10. Design of a quasi-isochronous storage ring for THz light source%用于太赫兹光源的准等时性储存环的设计

    Institute of Scientific and Technical Information of China (English)

    朱家鹏; 徐宏亮; 冯光耀; 蓝杰钦

    2012-01-01

    A quasi-isochronous storage ring is designed by manipulating lattice parameters to introduce a negative dispersion function to the dispersion section. This quasi-isochronous storage ring is designed for a THz synchrotron radiation source. The simulation of the optics function and beam emittance shows its feasibility, and the tracing result of particles indicates that the designed ring has a good particle dynamic aperture. In addition, a three-dimensional model of the vacuum chamber used for photon radiation in the quasi-isochronous mode is also designed. The eigenmodes of the chamber are simulated, and characteristic parameters such as quality factor, power loss and characteristic impedance are also calculated. The result shows that the vacuum chamber has little effect on the circulating beam.%介绍了一种获得准等时性储存环的方案,即调节Lattice参数,在色散段引入负色散函数从而降低线性滑相因子,获得短束团.根据此方案设计了用于相干太赫兹光源的准等时性储存环,结果给出了线形光学函数曲线以及粒子的动力学孔径,表明了通过调节四极铁参数可以达到降低束团长度获得准等时性储存环的目的.还设计了用于准等时性储存环弯铁处的真空室的3维模型,并对其类腔体部分的本征模进行了计算,得到特性阻抗与品质因数的比值在10-3量级以下,表明类腔体部分对束流的影响很小.

  11. Environmental assessment for construction and operation of a Human Genome Laboratory at Lawrence Berkeley Laboratory, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-01

    Lawrence Berkeley Laboratory (LBL) proposes to construct and operate a new laboratory for consolidation of current and future activities of the Human Genome Center (HGC). This document addresses the potential direct, indirect, and cumulative environmental and human-health effects from the proposed facility construction and operation. This document was prepared in accordance the National Environmental Policy Act of 1969 (United States Codes 42 USC 4321-4347) (NEPA) and the US Department of Energy`s (DOE) Final Rule for NEPA Implementing Procedures [Code of Federal Regulations 10CFR 1021].

  12. The eRHIC Ring-Ring Collider Design

    CERN Document Server

    Wang, Fuhua; Beebe-Wang, Joanne; Deshpande, Abhay A; Farkhondeh, Manouchehr; Franklin, Wilbur; Graves, William; Litvinenko, Vladimir N; MacKay, William W; Milner, Richard; Montag, Christoph; Ozaki, Satoshi; Parker, Brett; Peggs, Steve; Ptitsyn, Vadim; Roser, Thomas; Tepikian, Steven; Trbojevic, Dejan; Tschalär, C; Wang, Dong; Zolfaghari, Abbasali; Zwart, Townsend; van der Laan, Jan

    2005-01-01

    The eRHIC ring-ring collider is the main design option of the future lepton-ion collider at Brookhaven National Laboratory. We report the revisions of the ring-ring collider design features to the baseline design presented in the eRHIC Zeroth Design Report (ZDR). These revisions have been made during the past year. They include changes of the interaction region which are required from the modifications in the design of the main detector. They also include changes in the lepton storage ring for high current operations as a result of better understandings of beam-beam interaction effects. The updated collider luminosity and beam parameters also take into account a more accurate picture of current and future operational aspects of RHIC.

  13. The little-studied cluster Berkeley 90 - III. Cluster parameters

    Science.gov (United States)

    Marco, Amparo; Negueruela, Ignacio

    2017-02-01

    The open cluster Berkeley 90 is the home to one of the most massive binary systems in the Galaxy, LS III +46°11, formed by two identical, very massive stars (O3.5 If* + O3.5 If*), and a second early-O system (LS III +46°12 with an O4.5 IV((f)) component at least). Stars with spectral types earlier than O4 are very scarce in the Milky Way, with no more than 20 examples. The formation of such massive stars is still an open question today, and thus the study of the environments where the most massive stars are found can shed some light on this topic. To this aim, we determine the properties and characterize the population of Berkeley 90 using optical, near-infrared and WISE photometry and optical spectroscopy. This is the first determination of these parameters with accuracy. We find a distance of 3.5^{+0.5}_{-0.5} kpc and a maximum age of 3 Ma. The cluster mass is around 1000 M⊙ (perhaps reaching 1500 M⊙ if the surrounding population is added), and we do not detect candidate runaway stars in the area. There is a second population of young stars to the southeast of the cluster that may have formed at the same time or slightly later, with some evidence for low-activity ongoing star formation.

  14. The little-studied cluster Berkeley 90. III. Cluster parameters

    CERN Document Server

    Marco, Amparo

    2016-01-01

    The open cluster Berkeley 90 is the home to one of the most massive binary systems in the Galaxy, LS III +46$^{\\circ}$11, formed by two identical, very massive stars (O3.5 If* + O3.5 If*), and a second early-O system (LS III +46$^{\\circ}$12 with an O4.5 IV((f)) component at least). Stars with spectral types earlier than O4 are very scarce in the Milky Way, with no more than 20 examples. The formation of such massive stars is still an open question today, and thus the study of the environments where the most massive stars are found can shed some light on this topic. To this aim, we determine the properties and characterize the population of Berkeley 90 using optical, near-infrared and WISE photometry and optical spectroscopy. This is the first determination of these parameters with accuracy. We find a distance of $3.5^{+0.5}_{-0.5}$ kpc and a maximum age of 3 Ma. The cluster mass is around $1000$ $M_{\\odot}$ (perhaps reaching $1500$ $M_{\\odot}$ if the surrounding population is added), and we do not detect cand...

  15. 有风时大型油罐密封圈火灾下油罐间的安全距离%Safe Distance of Large Storage Tank’s Seal Ring Fire Under Wind Condition

    Institute of Scientific and Technical Information of China (English)

    关新凤; 刘德俊; 魏亚峰; 祝贺; 葛岚; 杨萍

    2015-01-01

    针对有风时大型原油储罐火灾安全问题,以密封圈火灾着火油罐作为研究对象,采用编程软件对着火油罐的辐射区域进行模拟计算,进而确定储罐间的安全距离。研究结果表明,风速一定时,辐射热量随着距火焰的距离增加而降低;同一着火油罐,热辐射情况随着风速的加大而加剧;风速为4 m/s 时,相邻油罐间的安全距离为31.2 m。%With respect to the security issue of large storage tanks’ fire, taking crude oil tank’s seal ring fire as the research object, programming software was used to simulate and calculate the thermal radiation of burning storage tank, which can get the safe distance between the tanks. The study results show that, under the condition of certain weed speed, the thermal radiation decreases with increasing of the distance reaching the burning storage tank. For the same burning tank, with increasing of the wind speed, the thermal radiation increases. When the wind speed is 4 m/s, the safe distance between the tanks is 31.2 m.

  16. SUPRAMITRAL RING

    Directory of Open Access Journals (Sweden)

    Rajesh G

    2011-11-01

    Full Text Available Supra mitral ring is a rare cause for congenital mitral valve obstr uction. The reported incidence of supramitral ring is 0.2-0.4% in general population and 8% in patients with congenital mitral valve disease. The condition is characterized by an abnormal ridge of connective tissue often circumferential in shape ,on the atrial side of the mitral valve encroaching on the orifice of the mitral valve. It may adhere to the leaflets of the valve and restrict their movements. Although a supramitral ring may be rarely nonobstructive, it often results in mitral valve inflow obstruction.

  17. Determinantal rings

    CERN Document Server

    Bruns, Winfried

    1988-01-01

    Determinantal rings and varieties have been a central topic of commutative algebra and algebraic geometry. Their study has attracted many prominent researchers and has motivated the creation of theories which may now be considered part of general commutative ring theory. The book gives a first coherent treatment of the structure of determinantal rings. The main approach is via the theory of algebras with straightening law. This approach suggest (and is simplified by) the simultaneous treatment of the Schubert subvarieties of Grassmannian. Other methods have not been neglected, however. Principal radical systems are discussed in detail, and one section is devoted to each of invariant and representation theory. While the book is primarily a research monograph, it serves also as a reference source and the reader requires only the basics of commutative algebra together with some supplementary material found in the appendix. The text may be useful for seminars following a course in commutative ring theory since a ...

  18. Cave Rings

    Science.gov (United States)

    2010-10-13

    hypothesis, that cave rings are formed in the same manner as coffee rings[3], that is, due to the enhanced deposition at the edges of sessile drops ...ring’ is the deposit formed when a sessile drop of a solution containing dissolved particles, such as coffee or salt, dries. This was investigated by...who expanded on Deegan et al.[3] to find an exact form for the evaporation flux over a sessile drop . It turns out that solving 179 for the flux is

  19. Spin flipping in rings with Siberian Snakes

    Energy Technology Data Exchange (ETDEWEB)

    Mane, S.R. [Convergent Computing Inc., P.O. Box 561, Shoreham, NY 11786 (United States)], E-mail: srmane@optonline.net

    2009-07-01

    I display numerical spin tracking simulations for spin flippers in model storage rings with full or nearly full Siberian Snakes. In many cases, the results differ from the predictions using the Froissart-Stora formula.

  20. BVI photometry of the very old open cluster Berkeley 17

    CERN Document Server

    Bragaglia, A; Marconi, G; Tosi, M; Andreuzzi, Gloria; Bragaglia, Angela; Marconi, Gianni; Tosi, Monica

    2006-01-01

    We have obtained BVI CCD imaging of Berkeley 17, an anticentre open cluster that competes with NGC 6791 as the oldest known open cluster. Using the synthetic colour magnitude diagrams (CMD) technique with three sets of evolutionary tracks we have determined that its age is 8.5 - 9.0 Gyr, it distance modulus is (m-M)_0 = 12.2, with a reddening of E(B-V) = 0.62 - 0.60. Differential reddening, if present, is at the 5 % level. All these values have been obtained using models with metallicity about half of solar (Z=0.008 or Z=0.01 depending on the stellar evolution tracks), which allows us to reproduce the features of the cluster CMD better than other metallicities. Finally, from the analysis of a nearby comparison field we think to have intercepted a portion of the disrupting Canis Major dwarf galaxy.

  1. Visualization and communication of pharmacometric models with berkeley madonna.

    Science.gov (United States)

    Krause, A; Lowe, P J

    2014-05-28

    Population or other pharmacometric models are a useful means to describe, succinctly, the relationships between drug administration, exposure (concentration), and downstream changes in pharmacodynamic (PD) biomarkers and clinical endpoints, including the mixed effects of patient factors and random interpatient variation (fixed and random effects). However, showing a set of covariate equations to a drug development team is perhaps not the best way to get a message across. Visualization of the consequences of the knowledge encapsulated within the model is the key component. Yet in many instances, it can take hours, perhaps days, to collect ideas from teams, write scripts, and run simulations before presenting the results-by which time they have moved on. How much better, then, to seize the moment and work interactively to decide on a course of action, guided by the model. We exemplify here the visualization of pharmacometric models using the Berkeley Madonna software with a particular focus on interactive sessions. The examples are provided as Supplementary Material.

  2. Early History of Heavy Isotope Research at Berkeley

    Energy Technology Data Exchange (ETDEWEB)

    Glenn T. Seaborg

    1976-06-01

    I have had the idea for some time that it would be interesting and worthwhile to put together an account of the early work on heavy isotopes at Berkeley. Of a special interest is the discovery of plutonium (atomic number 94) and the isotope U{sup 233}, and the demonstration of their fission with slow neutrons. This work served as a prelude to the subsequent Plutonium Project (Metallurgical Project) centered at the University of Chicago, in connection with which I have also had the idea of putting together a history of the work of my chemistry group. I have decided that it would be an interesting challenge to write this account on a day-to-day basis in a style that would be consistent with the entries having been written at the end of each day. The aim would be to make this history as accurate as possible by going back to the original records and using them with meticulous care.

  3. Narrative and Spectacle in the Hollywood Musical: Contrasting the Choreography of Busby Berkeley and Gene Kelly

    Science.gov (United States)

    Pattullo, Lauren

    2007-01-01

    This paper examines the relationship between narrative and spectacle in the Hollywood musical, with reference to the work of Busby Berkeley and Gene Kelly. It discusses Busby Berkeley's "backstage" musicals in terms of his "aggregate" approach to dealing with the narrative/spectacle relationship, and considers the effect of the backstage musical's…

  4. Morphological and functional platelet abnormalities in Berkeley sickle cell mice.

    Science.gov (United States)

    Shet, Arun S; Hoffmann, Thomas J; Jirouskova, Marketa; Janczak, Christin A; Stevens, Jacqueline R M; Adamson, Adewole; Mohandas, Narla; Manci, Elizabeth A; Cynober, Therese; Coller, Barry S

    2008-01-01

    Berkeley sickle cell mice are used as animal models of human sickle cell disease but there are no reports of platelet studies in this model. Since humans with sickle cell disease have platelet abnormalities, we studied platelet morphology and function in Berkeley mice (SS). We observed elevated mean platelet forward angle light scatter (FSC) values (an indirect measure of platelet volume) in SS compared to wild type (WT) (37+/-3.2 vs. 27+/-1.4, mean+/-SD; p<0.001), in association with moderate thrombocytopenia (505+/-49 x 10(3)/microl vs. 1151+/-162 x 10(3)/microl; p<0.001). Despite having marked splenomegaly, SS mice had elevated levels of Howell-Jolly bodies and "pocked" erythrocytes (p<0.001 for both) suggesting splenic dysfunction. SS mice also had elevated numbers of thiazole orange positive platelets (5+/-1% vs. 1+/-1%; p<0.001), normal to low plasma thrombopoietin levels, normal plasma glycocalicin levels, normal levels of platelet recovery, and near normal platelet life spans. Platelets from SS mice bound more fibrinogen and antibody to P-selectin following activation with a threshold concentration of a protease activated receptor (PAR)-4 peptide compared to WT mice. Enlarged platelets are associated with a predisposition to arterial thrombosis in humans and some humans with SCD have been reported to have large platelets. Thus, additional studies are needed to assess whether large platelets contribute either to pulmonary hypertension or the large vessel arterial occlusion that produces stroke in some children with sickle cell disease.

  5. Subjektiv idealisme møder virtuel virkelighed: George Berkeley og Second Life

    DEFF Research Database (Denmark)

    Grund, Cynthia M.; Pilegaard, Jesper

    Filosoffen George Berkeleys (1685-1753) velkendte motto var esse est percipi aut percipere: to be is to be perceived or to perceive. Berkeleys hensigt var at kortlægge en forståelse af den virkelige verden som noget, der kun bestod af bevidstheder og bevidsthedsindhold, perceivers and perceptions....... Berkeleys filosofi indeholder mange elementer, som gør, at den er relevant i forhold til de filosofiske spørgsmål, der trænger sig på i relation til den voksende sammenfletning, vi oplever mellem it-styret virtuel virkelighed og den aktuelle virkelighed. Second Life, et open access online virtuel univers......, er et eksempel på denne form for virtuel virkelighed, hvor Berkeleys filosofi giver en rig kontekst for refleksion over forholdene mellem perceivers og perceptions. Berkeleys amerikanske hjem 1729-1731 bærer navnet Whitehall. På SDU's virtuelle campus i Second Life, SDUSL, findes der et virtuelt...

  6. Topological rings

    CERN Document Server

    Warner, S

    1993-01-01

    This text brings the reader to the frontiers of current research in topological rings. The exercises illustrate many results and theorems while a comprehensive bibliography is also included. The book is aimed at those readers acquainted with some very basic point-set topology and algebra, as normally presented in semester courses at the beginning graduate level or even at the advanced undergraduate level. Familiarity with Hausdorff, metric, compact and locally compact spaces and basic properties of continuous functions, also with groups, rings, fields, vector spaces and modules, and with Zorn''s Lemma, is also expected.

  7. 77 FR 75448 - Welded Tube-Berkeley Including On-Site Leased Workers From Snelling, Aerotek and Express...

    Science.gov (United States)

    2012-12-20

    ... Employment and Training Administration Welded Tube--Berkeley Including On-Site Leased Workers From Snelling... Worker Adjustment Assistance on October 10, 2012, applicable to workers of Welded Tube--Berkeley... Welded Tube-- Berkeley. The Department has determined that these workers were sufficiently under...

  8. Ring interferometry

    CERN Document Server

    Malykin, Grigorii B; Zhurov, Alexei

    2013-01-01

    This monograph is devoted to the creation of a comprehensive formalism for quantitative description of polarized modes' linear interaction in modern single-mode optic fibers. The theory of random connections between polarized modes, developed in the monograph, allows calculations of the zero shift deviations for a fiber ring interferometer. The monograph addresses also the

  9. On SAP-rings

    OpenAIRE

    Zhixiang, Wu

    2006-01-01

    The rings whose simple right modules are absolutely pure are called right $SAP$-rings. We give a new characterization of right $SAP$ rings, right $V$ rings, and von Neumann regular rings. We also obtain a new decomposition theory of right selfinjective von Neumann regular rings. The relationships between $SAP$-rings, $V$-rings, and von Neumann regular rings are explored. Some recent results obtained by Faith are generalized and the results of Wu-Xia are strengthened.

  10. The BErkeley Atmospheric CO2 Observation Network: initial evaluation

    Science.gov (United States)

    Shusterman, Alexis A.; Teige, Virginia E.; Turner, Alexander J.; Newman, Catherine; Kim, Jinsol; Cohen, Ronald C.

    2016-10-01

    With the majority of the world population residing in urban areas, attempts to monitor and mitigate greenhouse gas emissions must necessarily center on cities. However, existing carbon dioxide observation networks are ill-equipped to resolve the specific intra-city emission phenomena targeted by regulation. Here we describe the design and implementation of the BErkeley Atmospheric CO2 Observation Network (BEACO2N), a distributed CO2 monitoring instrument that utilizes low-cost technology to achieve unprecedented spatial density throughout and around the city of Oakland, California. We characterize the network in terms of four performance parameters - cost, reliability, precision, and systematic uncertainty - and find the BEACO2N approach to be sufficiently cost-effective and reliable while nonetheless providing high-quality atmospheric observations. First results from the initial installation successfully capture hourly, daily, and seasonal CO2 signals relevant to urban environments on spatial scales that cannot be accurately represented by atmospheric transport models alone, demonstrating the utility of high-resolution surface networks in urban greenhouse gas monitoring efforts.

  11. The berkeley wavelet transform: a biologically inspired orthogonal wavelet transform.

    Science.gov (United States)

    Willmore, Ben; Prenger, Ryan J; Wu, Michael C-K; Gallant, Jack L

    2008-06-01

    We describe the Berkeley wavelet transform (BWT), a two-dimensional triadic wavelet transform. The BWT comprises four pairs of mother wavelets at four orientations. Within each pair, one wavelet has odd symmetry, and the other has even symmetry. By translation and scaling of the whole set (plus a single constant term), the wavelets form a complete, orthonormal basis in two dimensions. The BWT shares many characteristics with the receptive fields of neurons in mammalian primary visual cortex (V1). Like these receptive fields, BWT wavelets are localized in space, tuned in spatial frequency and orientation, and form a set that is approximately scale invariant. The wavelets also have spatial frequency and orientation bandwidths that are comparable with biological values. Although the classical Gabor wavelet model is a more accurate description of the receptive fields of individual V1 neurons, the BWT has some interesting advantages. It is a complete, orthonormal basis and is therefore inexpensive to compute, manipulate, and invert. These properties make the BWT useful in situations where computational power or experimental data are limited, such as estimation of the spatiotemporal receptive fields of neurons.

  12. Berkeley PHOG: PhyloFacts orthology group prediction web server.

    Science.gov (United States)

    Datta, Ruchira S; Meacham, Christopher; Samad, Bushra; Neyer, Christoph; Sjölander, Kimmen

    2009-07-01

    Ortholog detection is essential in functional annotation of genomes, with applications to phylogenetic tree construction, prediction of protein-protein interaction and other bioinformatics tasks. We present here the PHOG web server employing a novel algorithm to identify orthologs based on phylogenetic analysis. Results on a benchmark dataset from the TreeFam-A manually curated orthology database show that PHOG provides a combination of high recall and precision competitive with both InParanoid and OrthoMCL, and allows users to target different taxonomic distances and precision levels through the use of tree-distance thresholds. For instance, OrthoMCL-DB achieved 76% recall and 66% precision on this dataset; at a slightly higher precision (68%) PHOG achieves 10% higher recall (86%). InParanoid achieved 87% recall at 24% precision on this dataset, while a PHOG variant designed for high recall achieves 88% recall at 61% precision, increasing precision by 37% over InParanoid. PHOG is based on pre-computed trees in the PhyloFacts resource, and contains over 366 K orthology groups with a minimum of three species. Predicted orthologs are linked to GO annotations, pathway information and biological literature. The PHOG web server is available at http://phylofacts.berkeley.edu/orthologs/.

  13. Tiger Team assessment of the Lawrence Berkeley Laboratory, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    1991-02-01

    This report documents the results of the Department of Energy's (DOE's) Tiger Team Assessment of the Lawrence Berkeley Laboratory (LBL) conducted from January 14 through February 15, 1991. The purpose of the assessment was to provide the Secretary of Energy with the status of environment, safety, and health (ES H) programs at LBL. The Tiger Team concluded that curtailment of cessation of any operations at LBL is not warranted. However, the number and breadth of findings and concerns from this assessment reflect a serious condition at this site. In spite of its late start, LBL has recently made progress in increasing ES H awareness at all staff levels and in identifying ES H deficiencies. Corrective action plans are inadequate, however, many compensatory actions are underway. Also, LBL does not have the technical expertise or training programs nor the tracking and followup to effectively direct and control sitewide guidance and oversight by DOE of ES H activities at LBL. As a result of these deficiencies, the Tiger Team has reservations about LBL's ability to implement effective actions in a timely manner and, thereby, achieve excellence in their ES H program. 4 figs., 24 tabs.

  14. Status of the UC-Berkeley SETI Efforts

    CERN Document Server

    Korpela, Eric J; Bankay, Robert; Cobb, Jeff; Howard, Andrew; Lebofsky, Matt; Siemion, Andrew P V; von Korff, Joshua; Werthimer, Dan

    2011-01-01

    We summarize radio and optical SETI programs based at the University of California, Berkeley. The SEVENDIP optical pulse search looks for ns time scale pulses at visible wavelengths using an automated 30 inch telescope. The ongoing SERENDIP V.v sky survey searches for radio signals at the 300 meter Arecibo Observatory. The currently installed configuration supports 128 million channels over a 200 MHz bandwidth with ~1.6 Hz spectral resolution. SETI@home uses the desktop computers of volunteers to analyze over 160 TB of data at taken at Arecibo looking for two types of continuous wave signals and two types of pulsed signals. A version to be released this summer adds autocorrelation analysis to look for complex wave forms that have been repeated (and overlayed) after a short delay. SETI@home will soon be processing data of Kepler exoplanet systems collected at the GBT. The Astropulse project is the first SETI search for $\\mu$s time scale dispersed pulses in the radio spectrum. We recently reobserved 114 sky loc...

  15. A study of the old galactic star cluster Berkeley 32

    CERN Document Server

    Richtler, T; Richtler, Tom; Sagar, Ram

    2001-01-01

    We present new CCD photometry of the distant old open star cluster Berkeley 32 in Johnson V and Cousins I passbands. A total of about 3200 stars have been observed in a field of 13X13 arcmin**2. The colour-magnitude diagram in V, (V-I) has been generated down to V = 22 mag. A broad but well defined main sequence is clearly visible. Some blue stragglers, a well developed subgiant branch and a Red Clump are also seen. By fitting isochrones to this CMD as well as to other CMDs available in the literature, and using the Red Clump location, the reddening, distance and age of the star cluster have been determined. The cluster has a distance of 3.3 kpc, its radius is about 2.4 pc; the reddening E(B-V) is 0.08 mag and the age is 6.3 Gyr. By comparison with theoretical isochrones, a metallicity of [Fe/H]= -0.2 dex has been estimated. We find a much flatter mass function than what has been found for young clusters. If the mass function is a power law dN/dm = const.*m**alpha, then we get alpha = -0.5+-0.3 in the mass ra...

  16. Berkeley lab checkpoint/restart (BLCR) for Linux clusters

    Science.gov (United States)

    Hargrove, Paul H.; Duell, Jason C.

    2006-09-01

    This article describes the motivation, design and implementation of Berkeley Lab Checkpoint/Restart (BLCR), a system-level checkpoint/restart implementation for Linux clusters that targets the space of typical High Performance Computing applications, including MPI. Application-level solutions, including both checkpointing and fault-tolerant algorithms, are recognized as more time and space efficient than system-level checkpoints, which cannot make use of any application-specific knowledge. However, system-level checkpointing allows for preemption, making it suitable for responding to ''fault precursors'' (for instance, elevated error rates from ECC memory or network CRCs, or elevated temperature from sensors). Preemption can also increase the efficiency of batch scheduling; for instance reducing idle cycles (by allowing for shutdown without any queue draining period or reallocation of resources to eliminate idle nodes when better fitting jobs are queued), and reducing the average queued time (by limiting large jobs to running during off-peak hours, without the need to limit the length of such jobs). Each of these potential uses makes BLCR a valuable tool for efficient resource management in Linux clusters.

  17. Distributed Embedded Real-time Database Engine Based on Berkeley DB%基于Berkeley DB核心嵌入式实时数据库引擎

    Institute of Scientific and Technical Information of China (English)

    黄志刚

    2007-01-01

    在研究Berkeley DB的基础上,对其数据模型、数据字典、网络特性、事务处理等方面进行优化,设计一个基于Berkeley DB核心的分布式嵌入实时数据库引擎.这种简洁的轻量级数据库系统更适合于嵌入式实时系统应用,可以为其提供更丰富的数据管理功能.

  18. Laboratories for the 21st Century: Case Studies, Molecular Foundry, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    2010-11-01

    This case study provides information on the Molecular Foundry, which incorporates Labs21 principles in its design and construction. The design includes many of the strategies researched at Lawrence Berkeley Laboratory for energy efficient cleanroom and data centers.

  19. Recent Studies of Proton Drip-Line Nuclei Using the Berkeley Gas-Filled Separator

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, M.W.; Batchelder, J.C.; Ninov, V.; Gregorich, K.E.; Toth, K.S.; Bingham, C.R.; Piechaczek, A.; Xu, X.J.; Powell, J.; Joosten, R.; Cerny, J.

    1999-10-07

    The Berkeley Gas-filled Separator provides new research opportunities at Lawrence Berkeley National Laboratory's X-Inch Cyclotron. The use of this apparatus for the study of proton drip-line nuclides is discussed. Preliminary results of {sup 78}Kr bombardments of {sup 102}Pd targets at mid-target energies of 360, 375 and 385 MeV are presented. Improvements planned partially as a result of this measurement are also discussed.

  20. Lawrence Berkeley Laboratory, Institutional Plan FY 1994--1999

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The Institutional Plan provides an overview of the Lawrence Berkeley Laboratory mission, strategic plan, scientific initiatives, research programs, environment and safety program plans, educational and technology transfer efforts, human resources, and facilities needs. For FY 1994-1999 the Institutional Plan reflects significant revisions based on the Laboratory`s strategic planning process. The Strategic Plan section identifies long-range conditions that will influence the Laboratory, as well as potential research trends and management implications. The Initiatives section identifies potential new research programs that represent major long-term opportunities for the Laboratory, and the resources required for their implementation. The Scientific and Technical Programs section summarizes current programs and potential changes in research program activity. The Environment, Safety, and Health section describes the management systems and programs underway at the Laboratory to protect the environment, the public, and the employees. The Technology Transfer and Education programs section describes current and planned programs to enhance the nation`s scientific literacy and human infrastructure and to improve economic competitiveness. The Human Resources section identifies LBL staff diversity and development program. The section on Site and Facilities discusses resources required to sustain and improve the physical plant and its equipment. The new section on Information Resources reflects the importance of computing and communication resources to the Laboratory. The Resource Projections are estimates of required budgetary authority for the Laboratory`s ongoing research programs. The Institutional Plan is a management report for integration with the Department of Energy`s strategic planning activities, developed through an annual planning process.

  1. The Astrophysics Major at the University of California, Berkeley

    Science.gov (United States)

    Arons, J.; Heiles, C.

    2001-12-01

    The Astrophysics major offered by the Berkeley Astronomy Department has been redesigned to reflect broad educational goals. Students preparing for graduate school study mostly Physics and Mathematics, leavened with four semesters of astrophysics at the sophomore and senior level. These courses make heavy use of their concurrent Physics and Math. Astrophysics and Physics majors differ in the astrophysics courses replacing other electives which a Physics major might choose. The major's redesign also opened the door to students who wish to pursue a major which gives them broad technical training without having graduate school as a goal. Many such students follow the same track as those pursuing the graduate school option; others take courses specifically designed for people with alternate careers in mind. The major change has been a laboratory requirement for all Astrophysics majors, in either track. We now have advanced undergraduate laboratories: optical, radio, and near infrared; details are on our web page. These share the common thread of development of deep capabilities in data gathering, analysis, and presentation. Students achieve expertise in these areas because the labs include the complete range of activities normally encountered in observational or experimental research. Students use laboratory equipment to measure the fundamental parameters of devices and systems, make astronomical observations with those systems, write software in UNIX and IDL to control equipment and analyze the results, and write formal lab reports in LATEX. We avoid ``black box'' or ``cookbook'' procedures . The students leave the course having gained experience and knowledge, and a ``feel'' for how to proceed when faced with sometimes recalcitrant equipment and imperfect data. A by product of the training has been an increase in student involvement in undergraduate research projects. These innovations have led to a major that has doubled in size and, in a quite unanticipated

  2. Lawrence Berkeley Laboratory Institutional Plan, FY 1993--1998

    Energy Technology Data Exchange (ETDEWEB)

    1992-10-01

    The FY 1993--1998 Institutional Plan provides an overview of the Lawrence Berkeley Laboratory mission, strategic plan, scientific initiatives, research programs, environment and safety program plans, educational and technology transfer efforts, human resources, and facilities needs. The Strategic Plan section identifies long-range conditions that can influence the Laboratory, potential research trends, and several management implications. The Initiatives section identifies potential new research programs that represent major long-term opportunities for the Laboratory and the resources required for their implementation. The Scientific and Technical Programs section summarizes current programs and potential changes in research program activity. The Environment, Safety, and Health section describes the management systems and programs underway at the Laboratory to protect the environment, the public, and the employees. The Technology Transfer and Education programs section describes current and planned programs to enhance the nation's scientific literacy and human infrastructure and to improve economic competitiveness. The Human Resources section identifies LBL staff composition and development programs. The section on Site and Facilities discusses resources required to sustain and improve the physical plant and its equipment. The Resource Projections are estimates of required budgetary authority for the Laboratory's ongoing research programs. The plan is an institutional management report for integration with the Department of Energy's strategic planning activities that is developed through an annual planning process. The plan identifies technical and administrative directions in the context of the National Energy Strategy and the Department of Energy's program planning initiatives. Preparation of the plan is coordinated by the Office for Planning and Development from information contributed by the Laboratory's scientific and support divisions.

  3. Lawrence Berkeley Laboratory Institutional Plan, FY 1993--1998

    Energy Technology Data Exchange (ETDEWEB)

    Chew, Joseph T.; Stroh, Suzanne C.; Maio, Linda R.; Olson, Karl R.; Grether, Donald F.; Clary, Mary M.; Smith, Brian M.; Stevens, David F.; Ross, Loren; Alper, Mark D.; Dairiki, Janis M.; Fong, Pauline L.; Bartholomew, James C.

    1992-10-01

    The FY 1993--1998 Institutional Plan provides an overview of the Lawrence Berkeley Laboratory mission, strategic plan, scientific initiatives, research programs, environment and safety program plans, educational and technology transfer efforts, human resources, and facilities needs. The Strategic Plan section identifies long-range conditions that can influence the Laboratory, potential research trends, and several management implications. The Initiatives section identifies potential new research programs that represent major long-term opportunities for the Laboratory and the resources required for their implementation. The Scientific and Technical Programs section summarizes current programs and potential changes in research program activity. The Environment, Safety, and Health section describes the management systems and programs underway at the Laboratory to protect the environment, the public, and the employees. The Technology Transfer and Education programs section describes current and planned programs to enhance the nation`s scientific literacy and human infrastructure and to improve economic competitiveness. The Human Resources section identifies LBL staff composition and development programs. The section on Site and Facilities discusses resources required to sustain and improve the physical plant and its equipment. The Resource Projections are estimates of required budgetary authority for the Laboratory`s ongoing research programs. The plan is an institutional management report for integration with the Department of Energy`s strategic planning activities that is developed through an annual planning process. The plan identifies technical and administrative directions in the context of the National Energy Strategy and the Department of Energy`s program planning initiatives. Preparation of the plan is coordinated by the Office for Planning and Development from information contributed by the Laboratory`s scientific and support divisions.

  4. Storage Ring Technology for Free Electron Lasers.

    Science.gov (United States)

    1984-04-01

    new starting mode, it is clear that an arbitrary third mode amplitude can be added 1ithout changing the result. It follows by induction that for an...du laser. On montre que la puissance moyenne est en accord avec la limite imposee par le chauffage du paquet d’electrons (limite de Renieri

  5. Multiscale degradations of storage ring FEL optics

    CERN Document Server

    Gatto, A; Amra, C; Boccara, C; Couprie, Marie Emmanuelle; De Ninno, G; Feigl, T; Garzella, D; Grewe, M; Kaiser, N; Marsi, M; Paoloni, S; Reita, V; Roger, J P; Torchio, P; Trovò, M; Walker, R; Wille, K

    2002-01-01

    The advanced understanding of the complete degradation phenomena is crucial in order to develop robust optics for FEL. Under very harsh Synchrotron Radiation conditions, results show that multiscale wavelength damages could be observed, inducing local crystalline structure modifications of the high optical index material with a severe increase of the surface roughness.

  6. Modes of storage ring coherent instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.M.

    1986-12-01

    Longitudinal impedance in a beam and various modes of longitudinal coherent instabilities are discussed. The coasting beam coherent instability, microwave instability, and single-bunch longitudinal coherent instabilities are considered. The Vlasov equation is formulated, and a method of solving it is developed. The synchrotron modes are treated, which take the possible bunch shape distortion fully into consideration. A method of treating the synchrotron mode coupling in the case of a small bunch is discussed which takes advantage of the fact that only a few of the synchrotron modes can contribute in such a case. The effect of many bunches on the coherent motion of the beam and the longitudinal symmetric coupled bunch modes are discussed. The transverse impedance is then introduced, and the transverse coasting beam instability is discussed. Various bunched beam instabilities are discussed, including both single bunch instabilities and coupled bunch instabilities. The Vlasov equation for transverse as well as longitudinal motion of particles is introduced as well as a method of solving it within a linear approximation. Head-tail modes and short bunch instabilities and strong coupling instabilities in the long bunch case are covered. (LEW)

  7. Search for EDMs using Storage Rings

    NARCIS (Netherlands)

    Onderwater, C.J.G.; Rathmann, F; Stroher, H; Gebel, R; Hanhart, C; Kacharava, A; Lehrach, A; Lorentz, B; Nikolaev, NN; Nogga, A

    2011-01-01

    Permanent electric dipole moments (EDMs) violate parity and time-reversal symmetry. Within the Standard Model (SM), they require CP violation and are many orders of magnitude below present experimental sensitivity. Many extensions of the SM predict much larger EDMs, which are therefore an excellent

  8. Origami rings

    CERN Document Server

    Buhler, Joe; de Launey, Warwick; Graham, Ron

    2010-01-01

    Motivated by a question in origami, we consider sets of points in the complex plane constructed in the following way. Let $L_\\alpha(p)$ be the line in the complex plane through $p$ with angle $\\alpha$ (with respect to the real axis). Given a fixed collection $U$ of angles, let $\\RU$ be the points that can be obtained by starting with $0$ and $1$, and then recursively adding intersection points of the form $L_\\alpha(p) \\cap L_\\beta(q)$, where $p, q$ have been constructed already, and $\\alpha, \\beta$ are distinct angles in $U$. Our main result is that if $U$ is a group with at least three elements, then $\\RU$ is a subring of the complex plane, i.e., it is closed under complex addition and multiplication. This enables us to answer a specific question about origami folds: if $n \\ge 3$ and the allowable angles are the $n$ equally spaced angles $k\\pi/n$, $0 \\le k < n$, then $\\RU$ is the ring $\\Z[\\zeta_n]$ if $n$ is prime, and the ring $\\Z[1/n,\\zeta_{n}]$ if $n$ is not prime, where $\\zeta_n := \\exp(2\\pi i/n)$ is ...

  9. UXO Detection and Characterization using new Berkeley UXO Discriminator (BUD)

    Science.gov (United States)

    Gasperikova, E.; Morrison, H. F.; Smith, J. T.; Becker, A.

    2006-05-01

    An optimally designed active electromagnetic system (AEM), Berkeley UXO Discriminator, BUD, has been developed for detection and characterization of UXO in the 20 mm to 150 mm size range. The system incorporates three orthogonal transmitters, and eight pairs of differenced receivers. The transmitter-receiver assembly together with the acquisition box, as well as the battery power and GPS receiver, is mounted on a small cart to assure system mobility. BUD not only detects the object itself but also quantitatively determines its size, shape, orientation, and metal content (ferrous or non-ferrous, mixed metals). Moreover, the principal polarizabilities and size of a metallic target can be determined from a single position of the BUD platform. The search for UXO is a two-step process. The object must first be detected and its location determined then the parameters of the object must be defined. A satisfactory classification scheme is one that determines the principal dipole polarizabilities of a target. While UXO objects have a single major polarizability (principal moment) coincident with the long axis of the object and two equal transverse polarizabilities, the scrap metal has all three principal moments entirely different. This description of the inherent polarizabilities of a target is a major advance in discriminating UXO from irregular scrap metal. Our results clearly show that BUD can resolve the intrinsic polarizabilities of a target and that there are very clear distinctions between symmetric intact UXO and irregular scrap metal. Target properties are determined by an inversion algorithm, which at any given time inverts the response to yield the location (x, y, z) of the target, its attitude and its principal polarizabilities (yielding an apparent aspect ratio). Signal-to-noise estimates (or measurements) are interpreted in this inversion to yield error estimates on the location, attitude and polarizabilities. This inversion at a succession of times provides

  10. SETI Programs at the University of California, Berkeley

    Science.gov (United States)

    Korpela, E. J.; Siemion, A. V. P.; Werthimer, D.; Korff, J. V.; Gautham, A.; Cobb, J.; Lebofsky, M.; Dexter, M.; MacMahon, D.; Wright, S.

    2014-03-01

    I describe recent SETI efforts by the University of California, Berkeley SETI Research center and efforts to be undertaken in the near future. In addition to our well known SETI@home (Korpela 2011) and Astropulse (Von Korff et al. 2013) public participation SETI survey projects, we have performed several targeted obsevations of different object classes. These include 1) Observations between 1.1 and 1.9 GHz of planetary systems idenfied by Kepler as containing earthlike planets in or near the habitable zones. (Siemion et al. 2013) 2) Wide-band Arecibo observations of 112 sky locations where the Astropulse project has identified strong µs duration dispersed radio pulses. 3) Observations of Kepler identified planetary systems at times when two planets would appear to be in conjuction when viewed from Earth. We plan a future campaign to simultaneously observe known planetary systems at radio, optical and IR wavelengths. We have also continued to advance our instrumentation. We are currently building the sixth generation of our SERENDIP (Siemion et al. 2011, Korpela et al. 2011) series of SETI instrumentation for installation at both Arecibo and GBT. SERENDIP VI will utilize an FPGA based polyphase filter bank course spectrometer feeding 8 or more GPU based compute nodes. The Arecibo version of this spectrometer will be capable of providing thresholded 1Hz resolution spectra of all seven beams of the 320 MHz bandwidth Arecibo L-band Feed Array in dual polarization. A separate front end will be available to allow up to 2.2 GHz of bandwidth in dual polarization from single pixel receivers. The Green Bank version of this spectrometer will utilize the single pixel front end. We are invesitating the possibility of simultaneous back end stages operating on the same or minimal processed data, for example, we could support simulataneous detection of fast extragalactic radio bursts (Thornton et al. 2013) by adding additional compute nodes. We are also developing new instruments

  11. Collecting and Using Low Latency Data at Berkeley Seismological Laboratory

    Science.gov (United States)

    Houlié, N.; Allen, R.; Hellweg, P.; Dreger, D.; Neuhauser, D.; Romanowicz, B.

    2008-12-01

    Northern California and the San Francisco Bay Area are among the US regions that combine high earthquake hazard and high population density. To rapidly and reliably monitor tectonic movement and develop an understanding of fault dynamics, measurements must cover a range of scales in time (0.1 s to years), space (mms to 100s of km) and displacement (microns to 10s of m). With these goals in mind, Berkeley Seismological Laboratory (BSL) continuously collects a wide variety of data at low latencies from seismic through geodetic, strain and electromagnetic instrumentation with sampling rates spanning 0.001 sps to 500 sps. Data from broadband seismometers and accelerometers, generally with latencies of less than 10 s, contribute to real time earthquake monitoring in Northern California including rapid assessments of source (moment tensor and finite fault) and shaking (ShakeMap). The BSL is also currently operating a real time system in test mode, using these data for earthquake early warning (ElarmS). Data from these instruments are also used for research on earthquake sources and scaling, fault-related tremor and studies of local, regional and global velocity structure. Low latency GPS data can complement seismic data, contributing robust real time continuous information especially for large earthquakes, and can potentially contribute to early warning. GPS-derived static deformation gives an independent estimate of fault orientation and dimensions, scalar seismic moment and magnitude. It also can extend the upper limits of a strong motion network to include the displacements of tens of meters expected in large and great earthquakes, and in the near field is less likely to be clipped during large movements. In an active tectonic context such as Northern California, low latency is important for data transmission, but also for reliability. At the BSL we are committed to using telemetry that is as robust as possible and often have more than one telemetry path to ensure

  12. Energy Storage.

    Science.gov (United States)

    Eaton, William W.

    Described are technological considerations affecting storage of energy, particularly electrical energy. The background and present status of energy storage by batteries, water storage, compressed air storage, flywheels, magnetic storage, hydrogen storage, and thermal storage are discussed followed by a review of development trends. Included are…

  13. Bunch-by-bunch beam loss monitor system in BEPCⅡ storage ring%BEPCⅡ储存环逐束团丢束监测系统及应用

    Institute of Scientific and Technical Information of China (English)

    邓庆勇; 曹建社; 岳军会; 魏源源; 麻惠洲; 杜垚垚

    2014-01-01

    A new prototype system for bunch-by-bunch beam position measurement has been designed and built to monitor and analyse the beam loss in the Beijing Electron-Positron ColliderⅡ(BEPCⅡ)storage ring.The fast ADC is used to sample the analog signals from the beam position monitor,then the digital signal is processed further using programmable gate array (FP-GA).The beam information can be obtained by means of bunch-by-bunch,such as bunch position,bunch current and bunch tune.Based on system monitoring and data analysis for long terms,as well as the dedicated machine experiments,it’s relatively clear for operators to understand some trip events,especially the beam loss caused by the high-frequency cavity trip,tune drift and multiple bunch instability.The study proves that the system is very useful for the operation of accelerator.%针对北京正负电子对撞机二期工程(BEPCⅡ)在高流强下运行经常出现的突然丢束问题,研制了基于逐束团测量的丢束监测系统。束流位置探头(BPM)的四路电极信号作为监测系统的信号源,四路高速模数转换器(ADC)和现场可编程门阵列(FPGA)进行模拟信号的数字化和数字信号的处理。通过获取丢束前每个束团的位置和流强等信息来分析引起丢束的原因。结合加速器硬件情况,长时间对丢束监测系统数据的分析,以及设计的对比实验,深入研究丢束问题。系统对高频系统故障、束流不稳定性和磁铁电源系统不稳定等原因引起的丢束现象可以做出准确的判断,进而为加速器稳定运行提供优化方向。

  14. Berkeley e o papel das hipóteses na filosofia natural Berkeley and the role of hypothesis in natural philosophy

    Directory of Open Access Journals (Sweden)

    Silvio Seno Chibeni

    2010-09-01

    Full Text Available A questão do estatuto epistemológico das hipóteses que postulam entes e mecanismos inobserváveis tornou-se proeminente com o advento da ciência moderna, no século XVII. Uma das razões para isso é que, por um lado, as novas teorias científicas passaram a empregá-las amplamente na explicação dos fenômenos naturais, enquanto que, por outro lado, a epistemologia empirista, geralmente adotada desde então para a análise da ciência, parecia proscrever seu uso. Neste artigo analisam-se as soluções propostas por George Berkeley para essa tensão. Mostra-se que nos Princípios do conhecimento humano ele introduz uma nova noção de explicação científica, segundo a qual a ciência poderia prescindir de hipóteses sobre inobserváveis, quaisquer que sejam. Depois, para acomodar epistemologicamente a mecânica newtoniana, ele propõe, no De motu, a interpretação instrumentalista das hipóteses sobre forças, que são centrais nessa teoria, considerada por ele "a melhor chave para a ciência natural". Finalmente, em sua obra tardia, Siris, Berkeley envolve-se, de forma aparentemente realista, na discussão e defesa de uma série de hipóteses sobre fluidos inobserváveis. Examina-se brevemente, no final do artigo, a possibilidade de conciliar essa posição com os princípios fundamentais da epistemologia e metafísica de Berkeley.The issue of the epistemological status of hypotheses postulating unobservable entities became prominent with the advent of modern science, in the 17th century. The basic reason is that such entities were widely employed by the new scientific theories in the explanation and prediction of natural phenomena, whereas empiricist epistemology, which at that time became very popular among philosophers and scientists, formed a clearly inhospitable background for unobservable elements in general. This paper examines the stands adopted, and the proposals made on this topic by George Berkeley, one of the most important

  15. Prime rings with PI rings of constants

    CERN Document Server

    Kharchenko, V K; Rodríguez-Romo, S

    1996-01-01

    It is shown that if the ring of constants of a restricted differential Lie algebra with a quasi-Frobenius inner part satisfies a polynomial identity (PI) then the original prime ring has a generalized polynomial identitiy (GPI). If additionally the ring of constants is semiprime then the original ring is PI. The case of a non-quasi-Frobenius inner part is also considered.

  16. The Indirect Perception of Distance: Interpretive Complexities in Berkeley's Theory of Vision

    Directory of Open Access Journals (Sweden)

    Michael James Braund

    2007-12-01

    Full Text Available The problem of whether perception is direct or if it depends on additional, cognitive contributions made by the perceiving subject, is posed with particular force in an Essay towards a New Theory of Vision (NTV. It is evident from the recurrent treatment it receives therein that Berkeley considers it to be one of the central issues concerning perception. Fittingly, the NTV devotes the most attention to it. In this essay, I deal exclusively with Berkeley's treatment of the problem of indirect distance perception, as it is presented in the context of that work.

  17. A community of scientists: cultivating scientific identity among undergraduates within the Berkeley Compass Project

    Science.gov (United States)

    Aceves, Ana V.; Berkeley Compass Project

    2015-01-01

    The Berkeley Compass Project is a self-formed group of graduate and undergraduate students in the physical sciences at UC Berkeley. Our goals are to improve undergraduate physics education, provide opportunities for professional development, and increase retention of students from populations typically underrepresented in the physical sciences. For students who enter as freshmen, the core Compass experience consists of a summer program and several seminar courses. These programs are designed to foster a diverse, collaborative student community in which students engage in authentic research practices and regular self-reflection. Compass encourages undergraduates to develop an identity as a scientist from the beginning of their university experience.

  18. Radical theory of rings

    CERN Document Server

    Gardner, JW

    2003-01-01

    Radical Theory of Rings distills the most noteworthy present-day theoretical topics, gives a unified account of the classical structure theorems for rings, and deepens understanding of key aspects of ring theory via ring and radical constructions. Assimilating radical theory's evolution in the decades since the last major work on rings and radicals was published, the authors deal with some distinctive features of the radical theory of nonassociative rings, associative rings with involution, and near-rings. Written in clear algebraic terms by globally acknowledged authorities, the presentation

  19. The Berkeley Puppet Interview: A Screening Instrument for Measuring Psychopathology in Young Children

    Science.gov (United States)

    Stone, Lisanne L.; van Daal, Carlijn; van der Maten, Marloes; Engels, Rutger C. M. E.; Janssens, Jan M. A. M.; Otten, Roy

    2014-01-01

    Background: While child self-reports of psychopathology are increasingly accepted, little standardized instruments are utilized for these practices. The Berkeley Puppet Interview (BPI) is an age-appropriate instrument for self-reports of problem behavior by young children. Objective: Psychometric properties of the Dutch version of the BPI will be…

  20. Berkeley Foundation for Opportunities in Information Technology: A Decade of Broadening Participation

    Science.gov (United States)

    Crutchfield, Orpheus S. L.; Harrison, Christopher D.; Haas, Guy; Garcia, Daniel D.; Humphreys, Sheila M.; Lewis, Colleen M.; Khooshabeh, Peter

    2011-01-01

    The Berkeley Foundation for Opportunities in Information Technology is a decade-old endeavor to expose pre-college young women and underrepresented racial and ethnic minorities to the fields of computer science and engineering, and prepare them for rigorous, university-level study. We have served more than 150 students, and graduated more than 65…

  1. "A Woman's World": The University of California, Berkeley, during the Second World War

    Science.gov (United States)

    Dorn, Charles

    2008-01-01

    During World War II, female students at the University of California, Berkeley--then the most populous undergraduate campus in American higher education--made significant advances in collegiate life. In growing numbers, women enrolled in male-dominated academic programs, including mathematics, chemistry, and engineering, as they prepared for…

  2. UC Berkeley's Undocumented Student Program: Holistic Strategies for Undocumented Student Equitable Success across Higher Education

    Science.gov (United States)

    Sanchez, Ruben Elias Canedo; So, Meng L.

    2015-01-01

    In this essay, Ruben Elias Canedo Sanchez and Meng L. So share the history and development of the Undocumented Student Program at the University of California, Berkeley. In describing the creation of the program, the authors offer reflections on the strategies employed to holistically support undocumented students' success on campus. By drawing on…

  3. Follow the Money: Engineering at Stanford and UC Berkeley during the Rise of Silicon Valley

    Science.gov (United States)

    Adams, Stephen B.

    2009-01-01

    A comparison of the engineering schools at UC Berkeley and Stanford during the 1940s and 1950s shows that having an excellent academic program is necessary but not sufficient to make a university entrepreneurial (an engine of economic development). Key factors that made Stanford more entrepreneurial than Cal during this period were superior…

  4. Visual Access to Visual Images: The UC Berkeley Image Database Project.

    Science.gov (United States)

    Besser, Howard

    1990-01-01

    Discusses the problem of access in managing image collections and describes a prototype system for the University of California Berkeley which would include the University Art Museum, Architectural Slide Library, Geography Department's Map Library and Lowie Museum of Anthropology photographs. The system combines an online public access catalog…

  5. You Learn What You Eat: Cognition Meets Nutrition in Berkeley Schools.

    Science.gov (United States)

    Sobel, David

    2001-01-01

    In the past 5 years, the Center for Ecoliteracy's Food Systems Project has grown from one schoolyard garden to the complete reinvention of Child Nutrition Services throughout the Berkeley Unified School District. Using food as the organizing principle for systemic change, the project is devising a pattern of healthy food, improved academic…

  6. Fermilab and Berkeley Lab Collaborate with Meyer Tool on Key Component for European Particle Accelerator

    CERN Multimedia

    2004-01-01

    Officials of the U.S. Department of Energy's Fermi National Accelerator Laboratory and Lawrence Berkeley National Laboratory announced yesterday the completion of a key component of the U.S. contribution to the Large Hadron Collider, a particle accelerator under construction at CERN, in Geneva, Switzerland

  7. Ernest Orlando Lawrence Berkeley National Laboratory Institutional Plan FY 2000-2004

    Energy Technology Data Exchange (ETDEWEB)

    Chartock, Mike (ed.); Hansen, Todd (ed.)

    1999-08-01

    The FY 2000-2004 Institutional Plan provides an overview of the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab, the Laboratory) mission, strategic plan, initiatives, and the resources required to fulfill its role in support of national needs in fundamental science and technology, energy resources, and environmental quality. To advance the Department of Energy's ongoing efforts to define the Integrated Laboratory System, the Berkeley Lab Institutional Plan reflects the strategic elements of our planning efforts. The Institutional Plan is a management report that supports the Department of Energy's mission and programs and is an element of the Department of Energy's strategic management planning activities, developed through an annual planning process. The Plan supports the Government Performance and Results Act of 1993 and complements the performance-based contract between the Department of Energy and the Regents of the University of California. It identifies technical and administrative directions in the context of the national energy policy and research needs and the Department of Energy's program planning initiatives. Preparation of the plan is coordinated by the Office of Planning and Communications from information contributed by Berkeley Lab's scientific and support divisions.

  8. Stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  9. Birth Control Ring

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Birth Control Ring KidsHealth > For Teens > Birth Control Ring A A A What's in this article? ... español Anillo vaginal anticonceptivo What Is It? The birth control ring is a soft, flexible, doughnut-shaped ring ...

  10. Multiple Landslide-Hazard Scenarios Modeled for the Oakland-Berkeley Area, Northern California

    Science.gov (United States)

    Pike, Richard J.; Graymer, Russell W.

    2008-01-01

    With the exception of Los Angeles, perhaps no urban area in the United States is more at risk from landsliding, triggered by either precipitation or earthquake, than the San Francisco Bay region of northern California. By January each year, seasonal winter storms usually bring moisture levels of San Francisco Bay region hillsides to the point of saturation, after which additional heavy rainfall may induce landslides of various types and levels of severity. In addition, movement at any time along one of several active faults in the area may generate an earthquake large enough to trigger landslides. The danger to life and property rises each year as local populations continue to expand and more hillsides are graded for development of residential housing and its supporting infrastructure. The chapters in the text consist of: *Introduction by Russell W. Graymer *Chapter 1 Rainfall Thresholds for Landslide Activity, San Francisco Bay Region, Northern California by Raymond C. Wilson *Chapter 2 Susceptibility to Deep-Seated Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike and Steven Sobieszczyk *Chapter 3 Susceptibility to Shallow Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Kevin M. Schmidt and Steven Sobieszczyk *Chapter 4 Landslide Hazard Modeled for the Cities of Oakland, Piedmont, and Berkeley, Northern California, from a M=7.1 Scenario Earthquake on the Hayward Fault Zone by Scott B. Miles and David K. Keefer *Chapter 5 Synthesis of Landslide-Hazard Scenarios Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike The plates consist of: *Plate 1 Susceptibility to Deep-Seated Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike, Russell W. Graymer, Sebastian Roberts, Naomi B. Kalman, and Steven Sobieszczyk *Plate 2 Susceptibility to Shallow Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Kevin M. Schmidt and Steven

  11. Actin Rings of Power.

    Science.gov (United States)

    Schwayer, Cornelia; Sikora, Mateusz; Slováková, Jana; Kardos, Roland; Heisenberg, Carl-Philipp

    2016-06-20

    Circular or ring-like actin structures play important roles in various developmental and physiological processes. Commonly, these rings are composed of actin filaments and myosin motors (actomyosin) that, upon activation, trigger ring constriction. Actomyosin ring constriction, in turn, has been implicated in key cellular processes ranging from cytokinesis to wound closure. Non-constricting actin ring-like structures also form at cell-cell contacts, where they exert a stabilizing function. Here, we review recent studies on the formation and function of actin ring-like structures in various morphogenetic processes, shedding light on how those different rings have been adapted to fulfill their specific roles.

  12. Alternative loop rings

    CERN Document Server

    Goodaire, EG; Polcino Milies, C

    1996-01-01

    For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

  13. Cyclist safety on bicycle boulevards and parallel arterial routes in Berkeley, California.

    Science.gov (United States)

    Minikel, Eric

    2012-03-01

    This study compares the safety of bicyclists riding on bicycle boulevards to those riding on parallel arterial routes in Berkeley, California. Literature on the impact of motor vehicle traffic characteristics on cyclist safety shows that high motor vehicle speeds and volumes and the presence of heavy vehicles are all detrimental to cyclist safety. This suggests that cyclists may be safer on side streets than on busy arterials. Bicycle boulevards-traffic-calmed side streets signed and improved for cyclist use-purport to offer cyclists a safer alternative to riding on arterials. Police-reported bicycle collision data and manually collected cyclist count data from bicycle boulevards and parallel arterial routes in Berkeley, California from 2003 to 2010 are used to test the hypothesis that Berkeley's bicycle boulevards have lower cyclist collision rates and a lower proportion of bicycle collisions resulting in severe injury. While no significant difference is found in the proportion of collisions that are severe, results show that collision rates on Berkeley's bicycle boulevards are two to eight times lower than those on parallel, adjacent arterial routes. The difference in collision rate is highly statistically significant, unlikely to be caused by any bias in the collision and count data, and cannot be easily explained away by self-selection or safety in numbers. Though the used dataset is limited and the study design is correlational, this study provides some evidence that Berkeley's bicycle boulevards are safer for cyclists than its parallel arterial routes. The results may be suggestive that, more generally, properly implemented bicycle boulevards can provide cyclists with a safer alternative to riding on arterials.

  14. Booster extraction, booster-to-storage ring transport and storage ring injection for the ALS

    Energy Technology Data Exchange (ETDEWEB)

    Zisman, M.S.

    1988-03-01

    A status report on the design of the ALS injection system is presented. The various modifications that have occurred since the time of the ALS Conceptual Design Report in July, 1986 are described, along with the reasons for the changes. 1 ref., 12 figs.

  15. On JB-Rings

    Institute of Scientific and Technical Information of China (English)

    Huanyin CHEN

    2007-01-01

    A ring R is a QB-ring provided that aR + bR = R with a, b ∈ R implies that there exists a y ∈ R such that a+by ∈ R-1q. It is said that a ring R is a JB-ring provided that R/J(R) is a QB-ring, where J(R) is the Jacobson radical of R. In this paper, various necessary and sufficient conditions, under which a ring is a JB-ring, are established. It is proved that JB-rings can be characterized by pseudo-similarity. Furthermore, the author proves that R is a J B-ring iff so is R/J(R)2.

  16. On semi ring bornologies

    Science.gov (United States)

    Imran, A. N.; Rakhimov, I. S.; Husain, Sh. K. Said

    2016-06-01

    Our main focus in this work is to introduce new structure bornological semi rings. This generalizes the theory of algebraic semi rings from the algebraic setting to the framework of bornological sets. We give basic properties for this new structure. As well as, We study the fundamental construction of bornological semi ring as product, inductive limits and projective limits and their extensions on bornological semi ring. Additionally, we introduce the category of bornological semi rings and study product and pullback (fiber product) in the category of bornological semi rings.

  17. Proceedings of the 1997 Particle Accelerator Conference Held in Vancouver, B.C., Canada on 12-16 May, 1997. Volume 1: Plenary and Special Sessions; Accelerators and Storage Rings.

    Science.gov (United States)

    2007-11-02

    Construction reports range from the CERN Large Hadron Collider and the Fermilab Main Injector and Recycler, to the BESSY-II light source and the TRIUMF-ISAC...include the initial operation of the SPring-8 light source, the PEP-II B-factory high-energy ring, the CERN LEP2 collider , and one sextant of RHIC...radioactive beam facility. Upcoming projects described include the US Spallation Neutron Source, the Japanese Hadron Facility and the RIKEN Beam

  18. A Community of Scientists and Educators: The Compass Project at UC Berkeley

    Science.gov (United States)

    Roth, Nathaniel; Schwab, Josiah

    2016-01-01

    The Berkeley Compass Project is a self-formed group of graduate and undergraduate students in the physical sciences at the University of California, Berkeley. Its goals are to improve undergraduate physics education, provide opportunities for professional development, and increase retention of students from populations underrepresented in the physical sciences. For undergraduate students, the core Compass experience consists of a summer program and several seminar courses. These programs are designed to foster a diverse, collaborative student community in which students engage in authentic research practices and regular self-reflection. Graduate students, together with upper-level undergraduates, design and run all Compass programs. Compass strives to incorporate best practices from the science education literature. Experiences in Compass leave participants poised to be successful students researchers, teachers, and mentors.

  19. Construction and operation of replacement hazardous waste handling facility at Lawrence Berkeley Laboratory. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1992-09-01

    The US Department of Energy (DOE) has prepared an environmental assessment (EA), DOE/EA-0423, for the construction and operation of a replacement hazardous waste handling facility (HWHF) and decontamination of the existing HWHF at Lawrence Berkeley Laboratory (LBL), Berkeley, California. The proposed facility would replace several older buildings and cargo containers currently being used for waste handling activities and consolidate the LBL`s existing waste handling activities in one location. The nature of the waste handling activities and the waste volume and characteristics would not change as a result of construction of the new facility. Based on the analysis in the EA, DOE has determined that the proposed action would not constitute a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act (NEPA) of 1969, 42 USC. 4321 et seq. Therefore, an environmental impact statement is not required.

  20. Leibniz's Infinitesimals: Their Fictionality, Their Modern Implementations, And Their Foes From Berkeley To Russell And Beyond

    CERN Document Server

    Katz, Mikhail G; 10.1007/s10670-012-9370-y

    2012-01-01

    Many historians of the calculus deny significant continuity between infinitesimal calculus of the 17th century and 20th century developments such as Robinson's theory. Robinson's hyperreals, while providing a consistent theory of infinitesimals, require the resources of modern logic; thus many commentators are comfortable denying a historical continuity. A notable exception is Robinson himself, whose identification with the Leibnizian tradition inspired Lakatos, Laugwitz, and others to consider the history of the infinitesimal in a more favorable light. Inspite of his Leibnizian sympathies, Robinson regards Berkeley's criticisms of the infinitesimal calculus as aptly demonstrating the inconsistency of reasoning with historical infinitesimal magnitudes. We argue that Robinson, among others, overestimates the force of Berkeley's criticisms, by underestimating the mathematical and philosophical resources available to Leibniz. Leibniz's infinitesimals are fictions, not logical fictions, as Ishiguro proposed, but ...

  1. The SEMATECH Berkeley microfield exposure tool: learning a the 22-nm node and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Naulleau, Patrick; Anderson, Christopher; Baclea-an, Lorie-Mae; Denham, Paul; George, Simi; Goldberg, Kenneth A.; Goldstein, Michael; Hoef, Brian; Hudyma, Russ; Jones, Gideon; Koh, Chawon; La Fontaine, Bruno; McClinton, Brittany; Miyakawa, Ryan; Montgomery, Warren; Roller, John; Wallow, Tom; Wurm, Stefan

    2009-02-16

    Microfield exposure tools (METs) continue to playa dominant role in the development of extreme ultraviolet (EUV) resists. One of these tools is the SEMATECH Berkeley 0.3-NA MET operating as a SEMATECH resist and mask test center. Here we present an update summarizing the latest resist test and characterization results. The relatively small numerical aperture and limited illumination settings expected from 1st generation EUV production tools make resist resolution a critical issue even at the 32-nm node. In this presentation, sub 22 nm half pitch imaging results of EUV resists are reported. We also present contact hole printing at the 30-nm level. Although resist development has progressed relatively well in the areas of resolution and sensitivity, line-edge-roughness (LER) remains a significant concern. Here we present a summary of recent LER performance results and consider the effect of system-level contributors to the LER observed from the SEMA TECH Berkeley microfield tool.

  2. Clinical results of stereotactic hellium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Levy, R.P.; Fabrikant, J.I.; Lyman, J.T.; Frankel, K.A.; Phillips, M.H.; Lawrence, J.H.; Tobias, C.A.

    1989-12-01

    The first therapeutic clinical trial using accelerated heavy-charged particles in humans was performed at Lawrence Berkeley Laboratory (LBL) for the treatment of various endocrine and metabolic disorders of the pituitary gland, and as suppressive therapy for adenohypophyseal hormone-responsive carcinomas and diabetic retinopathy. In acromegaly, Cushing's disease, Nelson's syndrome and prolactin-secreting tumors, the therapeutic goal in the 433 patients treated has been to destroy or inhibit the growth of the pituitary tumor and control hormonal hypersecretion, while preserving a functional rim of tissue with normal hormone-secreting capacity, and minimizing neurologic injury. An additional group of 34 patients was treated for nonsecreting chromophobe adenomas. This paper discusses the methods and results of stereotactic helium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory. 11 refs.

  3. Stellar Mass Segregation in the Aged Galactic Open Star Cluster Berkeley 17

    CERN Document Server

    Bhattacharya, Souradeep; Vaidya, Kaushar; Chen, Wen-Ping

    2016-01-01

    We present the analysis of the morphology of Berkeley\\,17, the oldest known open cluster ($\\sim10$ Gyr), using a probabilistic star counting of Pan-STARRS point sources, and confirm its core-tail shape, plus an antitail, previously detected with 2MASS data. The stellar population, as diagnosed by the color-magnitude diagram and theoretical isochrones, shows more massive than lower-mass members in the cluster core, whereas there is a paucity of massive members in both tails. This manifests mass segregation in this aged star cluster with the low-mass members being stripped away from the system. It has been claimed that Berkeley 17 is associated with an excessive number of blue stragglers. Our analysis in comparison of the cluster with nearby reference fields indicates that about half of the blue stragglers may be field contaminations, and some may be confused with the rare blue horizontal-branch stars in this cluster.

  4. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  5. The Berkeley EUV/FUV Shuttle Telescope - Observations of dust reflection in the FUV

    Science.gov (United States)

    Hurwitz, Mark; Martin, Christopher; Bowyer, Stuart

    1986-01-01

    Observations by the Berkeley EUV/FUV Shuttle Telescope of the FUV reflection from dust clouds are reported. Spectra of the diffuse UV background from regions of low and high hydrogen column density have been taken. The intensity of the continuum correlates well with the column density of neutral hydrogen, and the slope of this correlation is interpreted with a simple model of optically thin scattering to obtain a measurement of a combination of the albedo and asymmetry parameter in the FUV.

  6. On Weakly Semicommutative Rings*

    Institute of Scientific and Technical Information of China (English)

    CHEN WEI-XING; CUI SHU-YING

    2011-01-01

    A ring R is said to be weakly scmicommutative if for any a, b ∈ R,ab = 0 implies aRb C_ Nil(R), where Nil(R) is the set of all nilpotcnt elements in R.In this note, we clarify the relationship between weakly semicommutative rings and NI-rings by proving that the notion of a weakly semicommutative ring is a proper generalization of NI-rings. We say that a ring R is weakly 2-primal if the set of nilpotent elements in R coincides with its Levitzki radical, and prove that if R is a weakly 2-primal ring which satisfies oα-condition for an endomorphism α of R (that is, ab = 0 (←→) aα(b) = 0 where a, b ∈ R) then the skew polynomial ring R[π; αα]is a weakly 2-primal ring, and that if R is a ring and I is an ideal of R such that I and R/I are both weakly semicommutative then R is weakly semicommutative.Those extend the main results of Liang et al. 2007 (Taiwanese J. Math., 11(5)(2007),1359-1368) considerably. Moreover, several new results about weakly semicommutative rings and NI-rings are included.

  7. The little-studied cluster Berkeley 90. II. The foreground ISM

    CERN Document Server

    Apellániz, J Maíz; Sota, A; Simón-Díaz, S

    2015-01-01

    Context: Nearly one century after their discovery, the carrier(s) of Diffuse Interstellar Bands is/are still unknown and there are few sightlines studied in detail for a large number of DIBs. Aims: We want to study the ISM sightlines towards LS III +46 11 and LS III +46 12, two early-O-type stellar systems, and LS III +46 11 B, a mid-B-type star. The three targets are located in the stellar cluster Berkeley 90 and have a high extinction. Methods: We use the multi-epoch high-S/N optical spectra presented in paper I (Ma\\'iz Apell\\'aniz et al. 2015), the extinction results derived there, and additional spectra. Results: We have measured equivalent widths, velocities, and FWHMs for a large number of absorption lines in the rich ISM spectrum in front of Berkeley 90. The absorbing ISM has at least two clouds at different velocities, one with a lower column density (thinner) in the K I lines located away from Berkeley 90 and another one with a higher column density (thicker) associated with the cluster. The first cl...

  8. A Radiation Homeland Security Workshop Presented to the City of Berkeley Fire Department

    Science.gov (United States)

    Matis, Howard

    2005-04-01

    A radiation incident in a community, ranging from a transportation accident to a dirty bomb, is expected to be rare, but still can occur. First responders to such an incident must be prepared. City of Berkeley officials met with members of the Lawrence Berkeley National Laboratory staff and agreed that the laboratory participants would create material and teach it to all of their fire fighting staff. To design such a course, nuclear physicists, biologists and health physicists merged some of their existing teaching material together with previous homeland security efforts to produce a course that lasted one full day. The material was designed to help alleviate the myths and fear of radiation experienced by many first responders. It included basic nuclear physics information, biological effects, and methods that health physicists use to detect and handle radiation. The curriculum included several hands on activities which involved working directly with the meters the Berkeley Fire Department possessed. In addition, I will discuss some observations from teaching this course material plus some unusual problems that we encountered, such as suddenly the whole class responding to a fire.

  9. Near-infrared photometry of the young open clusters NGC 1893 and Berkeley 86

    CERN Document Server

    Vallenari, A; Carraro, G; Girardi, L; Vallenari, Antonella; Richichi, Andrea; Carraro, Giovanni; Girardi, Leo

    1999-01-01

    We present photometry in the J and K near-infrared bands for two regions centered on the young open clusters NGC 1893 and Berkeley 86. We study 700 stars down to K = 17 in the field of NGC 1893, and about 2000 stars in the field of Berkeley 86 down to K$\\sim$ 16.5, for which near-infrared photometry was insofar not available. Coupling J-K data with UBV photometry taken from literature, we produce reddening corrected colour-magnitude diagrams. We find that our data are consistent with previous determinations: the clusters are roughly coeval with an age between 4 and 6 million years. The mean reddening (measured as E(J-K)) values turn out to be 0.35 and 0.50 for NGC 1893 and Berkeley 86, respectively.Using colour-colour plots we discuss the presence of candidate pre-main sequence stars showing infrared excess. Candidates are found in both cluster regions, confirming the young age of these clusters.

  10. Ernest Orlando Berkeley National Laboratory - Fundamental and applied research on lean premixed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Robert K.

    1999-07-07

    Ernest Orland Lawrence Berkeley National Laboratory (Berkeley Lab) is the oldest of America's national laboratories and has been a leader in science and engineering technology for more than 65 years, serving as a powerful resource to meet Us national needs. As a multi-program Department of Energy laboratory, Berkeley Lab is dedicated to performing leading edge research in the biological, physical, materials, chemical, energy, environmental and computing sciences. Ernest Orlando Lawrence, the Lab's founder and the first of its nine Nobel prize winners, invented the cyclotron, which led to a Golden Age of particle physics and revolutionary discoveries about the nature of the universe. To this day, the Lab remains a world center for accelerator and detector innovation and design. The Lab is the birthplace of nuclear medicine and the cradle of invention for medical imaging. In the field of heart disease, Lab researchers were the first to isolate lipoproteins and the first to determine that the ratio of high density to low density lipoproteins is a strong indicator of heart disease risk. The demise of the dinosaurs--the revelation that they had been killed off by a massive comet or asteroid that had slammed into the Earth--was a theory developed here. The invention of the chemical laser, the unlocking of the secrets of photosynthesis--this is a short preview of the legacy of this Laboratory.

  11. Berkeley Lab's Saul Perlmutter wins E.O. Lawrence Award; scientist's work on supernovae reveals accelerating Universe

    CERN Multimedia

    2002-01-01

    Saul Perlmutter, from Lawrence Berkeley National Laboratory Physics Division and leader of the Supernova Cosmology Project based there, has won the DOE's 2002 E.O. Lawrence Award in the physics category (2 pages).

  12. Physics of quantum rings

    CERN Document Server

    Fomin, Vladimir M

    2013-01-01

    This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is po

  13. Envelopes of Commutative Rings

    Institute of Scientific and Technical Information of China (English)

    Rafael PARRA; Manuel SAOR(I)N

    2012-01-01

    Given a significative class F of commutative rings,we study the precise conditions under which a commutative ring R has an F-envelope.A full answer is obtained when.F is the class of fields,semisimple commutative rings or integral domains.When F is the class of Noetherian rings,we give a full answer when the Krull dimension of R is zero and when the envelope is required to be epimorphic.The general problem is reduced to identifying the class of non-Noetherian rings having a monomorphic Noetherian envelope,which we conjecture is the empty class.

  14. RING PROXY SIGNATURES

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Proxy signatures have been used to enable the transfer of digital signing power within some context and ring signatures can be used to provide the anonymity of a signer. By combining the functionalities of proxy signatures and ring signatures, this paper introduces a new concept, named ring proxy signature, which is a proxy signature generated by an anonymous member from a set of potential signers. The paper also constructs the first concrete ring proxy signature scheme based on the provably secure Schnorr's signatures and two ID-based ring proxy signature schemes. The security analysis is provided as well.

  15. Hayward Fault rate constraints at Berkeley: Evaluation of the 335-meter Strawberry Creek offset

    Science.gov (United States)

    Williams, P. L.

    2007-12-01

    At UC Berkeley the active channel of Strawberry Creek is offset 335 meters by the Hayward fault and two abandoned channels of Strawberry Creek are laterally offset 580 and 730 meters. These relationships record the displacement of the northern Hayward fault at Berkeley over a period of tens of millennia. The Strawberry Creek site has a similar geometry to the central San Andreas fault's Wallace Creek site, which arguably provides the best geological evidence of "millennial" fault kinematics in California (Sieh and Jahns, 1984). Slip rate determinations are an essential component of overall hazard evaluation for the Hayward fault, and this site is ripe to disclose a long-term form of this parameter, to contrast with geodetic and other geological rate evidence. Large offsets at the site may lower uncertainty in the rate equation relative to younger sites, as the affect of stream abandonment age, generally the greatest source of rate uncertainty, is greatly reduced. This is helpful here because it more-than-offsets uncertainties resulting from piercing projections to the fault. Strawberry Creek and its ancestral channels suggest west-side-up vertical deformation across the Hayward fault at this location. The development of the vertical deformation parameter will complement ongoing geodetic measurements, particularly InSAR, and motivate testing of other geological constraints. Up-to-the-west motion across the Hayward fault at Berkeley has important implications for the partitioning of strain and kinematics of the northern Hayward fault, and may explain anomalous up-on-the-west landforms elsewhere along the fault. For example, geological features of the western Berkeley Hills are consistent with rapid and recent uplift to the west of the fault. On the basis of a preliminary analysis of the offset channels of Strawberry Creek, up-to-the-west uplift is about 0.5mm/yr across the Hayward fault at Berkeley. If this is in fact the long-term rate, the 150 m height of the Hills

  16. Saturn's largest ring.

    Science.gov (United States)

    Verbiscer, Anne J; Skrutskie, Michael F; Hamilton, Douglas P

    2009-10-22

    Most planetary rings in the Solar System lie within a few radii of their host body, because at these distances gravitational accelerations inhibit satellite formation. The best known exceptions are Jupiter's gossamer rings and Saturn's E ring, broad sheets of dust that extend outward until they fade from view at five to ten planetary radii. Source satellites continuously supply the dust, which is subsequently lost in collisions or by radial transport. Here we report that Saturn has an enormous ring associated with its outer moon Phoebe, extending from at least 128R(S) to 207R(S) (Saturn's radius R(S) is 60,330 km). The ring's vertical thickness of 40R(S) matches the range of vertical motion of Phoebe along its orbit. Dynamical considerations argue that these ring particles span the Saturnian system from the main rings to the edges of interplanetary space. The ring's normal optical depth of approximately 2 x 10(-8) is comparable to that of Jupiter's faintest gossamer ring, although its particle number density is several hundred times smaller. Repeated impacts on Phoebe, from both interplanetary and circumplanetary particle populations, probably keep the ring populated with material. Ring particles smaller than centimetres in size slowly migrate inward and many of them ultimately strike the dark leading face of Iapetus.

  17. The contraceptive vaginal ring.

    Science.gov (United States)

    Edwardson, Jill; Jamshidi, Roxanne

    2010-03-01

    The contraceptive vaginal ring offers effective contraception that is self-administered, requires less frequent dosing than many other forms of contraception, and provides low doses of hormones. NuvaRing (Organon, Oss, The Netherlands), the only contraceptive vaginal ring approved for use in the United States, contains etonogestrel and ethinyl estradiol. It is inserted into the vagina for 3 weeks, followed by a 1-week ring-free period, and works by inhibiting ovulation. Most women note a beneficial effect on bleeding profiles and are satisfied with NuvaRing. Commonly reported adverse events include vaginitis, leukorrhea, headaches, and device-related events such as discomfort. Serious adverse events are rare. In Chile and Peru, progesterone-only vaginal contraceptive rings are available for nursing women. Studies are ongoing examining new formulations of vaginal contraceptive rings.

  18. Certain near-rings are rings, II

    Directory of Open Access Journals (Sweden)

    Howard E. Bell

    1986-01-01

    Full Text Available We investigate distributively-generated near-rings R which satisfy one of the following conditions: (i for each x,y∈R, there exist positive integers m, n for which xy=ymxn; (ii for each x,y∈R, there exists a positive integer n such that xy=(yxn. Under appropriate additional hypotheses, we prove that R must be a commutative ring.

  19. Environmental assessment for the proposed construction and operation of a Genome Sequencing Facility in Building 64 at Lawrence Berkeley Laboratory, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This document is an Environmental Assessment (EA) for a proposed project to modify 14,900 square feet of an existing building (Building 64) at Lawrence Berkeley Laboratory (LBL) to operate as a Genome Sequencing Facility. This EA addresses the potential environmental impacts from the proposed modifications to Building 64 and operation of the Genome Sequencing Facility. The proposed action is to modify Building 64 to provide space and equipment allowing LBL to demonstrate that the Directed DNA Sequencing Strategy can be scaled up from the current level of 750,000 base pairs per year to a facility that produces over 6,000,000 base pairs per year, while still retaining its efficiency.

  20. Neutrosophic LA-Semigroup Rings

    Directory of Open Access Journals (Sweden)

    Mumtaz Ali

    2015-01-01

    Full Text Available Neutrosophic LA-semigroup is a midway structure between a neutrosophic groupoid and a commutative neutrosophic semigroup. Rings are the old concept in algebraic structures. We combine the neutrosophic LA-semigroup and ring together to form the notion of neutrosophic LA-semigroup ring. Neutrosophic LAsemigroup ring is defined analogously to neutrosophic group ring and neutrosophic semigroup ring.

  1. On Exchange QB∞-Rings

    Institute of Scientific and Technical Information of China (English)

    Huanyin Chen

    2007-01-01

    In this paper, we introduce a new class of rings, the QB∞-rings. We investigate necessary and sufficient conditions under which an exchange ring is a QB∞-ring. The modules over an exchange QB∞-ring are studied. Also, we prove that every regular square matrix over an exchange QB∞-ring admits a diagonal reduction by pseudo-invertible matrices.

  2. Token Ring Project

    Directory of Open Access Journals (Sweden)

    Adela Ionescu

    2007-01-01

    Full Text Available Ring topology is a simple configuration used to connect processes that communicate among themselves. A number of network standards such as token ring, token bus, and FDDI are based on the ring connectivity. This article will develop an implementation of a ring of processes that communicate among themselves via pipe links. The processes are nodes in the ring. Each process reads from its standard input and writes in its standard output. N-1 process redirects the its standard output to a standard input of the process through a pipe. When the ring-structure is designed, the project can be extended to simulate networks or to implement algorithms for mutual exclusion

  3. Gulf ring algae

    Science.gov (United States)

    Although they rank among the tiniest of the microspcopic phytoplankton, coccolithophore algae aid oceanographers studying the Gulf Stream rings and the ring boundaries. The algal group could help to identify more precisely the boundary of the warm rings of water that spin off from the Gulf Stream and become independent pools of warm water in the colder waters along the northeastern U.S. coast.Coccolithophore populations in the Gulf Stream rings intrigue oceanographers for two reasons: The phytoplankton are subjected to an environment that changes every few days, and population explosions within one coccolithophore species seem to be associated with changes in the characteristics of ocean water, said Pat Blackwelder, an associate professor at the Nova Oceanographic Center in Dania, Fla. She is one of many studying the physics, chemistry, and biology of warm core rings. A special oceanography session on these rings was held at the recent AGU Fall Meeting/ASLO Winter Meeting.

  4. Token ring technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This report provides an overview of the IBM Token-Ring technology and products built by IBM and compatible vendors. It consists of two sections: 1. A summary of the design trade-offs for the IBM Token-Ring. 2. A summary of the products of the major token-ring compatible vendors broken down by adapters and components, wiring systems, testing, and new chip technology.

  5. Dusty plasma (Yukawa) rings

    CERN Document Server

    Sheridan, T E

    2010-01-01

    One-dimensional and quasi-one-dimensional strongly-coupled dusty plasma rings have been created experimentally. Longitudinal (acoustic) and transverse (optical) dispersion relations for the 1-ring were measured and found to be in very good agreement with the theory for an unbounded straight chain of particles interacting through a Yukawa (i.e., screened Coulomb or Debye-H\\"uckel) potential. These rings provide a new system in which to study one-dimensional and quasi-one-dimensional physics.

  6. On -Coherent Endomorphism Rings

    Indian Academy of Sciences (India)

    Li-Xin Mao

    2008-11-01

    A ring is called right -coherent if every principal right ideal is finitely presented. Let $M_R$ be a right -module. We study the -coherence of the endomorphism ring of $M_R$. It is shown that is a right -coherent ring if and only if every endomorphism of $M_R$ has a pseudokernel in add $M_R; S$ is a left -coherent ring if and only if every endomorphism of $M_R$ has a pseudocokernel in add $M_R$. Some applications are given.

  7. Physics of quantum rings

    Energy Technology Data Exchange (ETDEWEB)

    Fomin, Vladimir M. (ed.) [Leibniz Institute for Solid State and Materials Research, Dresden (Germany)

    2014-07-01

    Presents the new class of materials of quantum rings. Provides an elemental basis for low-cost high-performance devices promising for electronics, optoelectronics, spintronics and quantum information processing. Explains the physical properties of quantum rings to cover a gap in scientific literature. Presents the application of most advanced nanoengineering and nanocharacterization techniques. This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is possible on the basis of modern characterization methods of nanostructures, such as Scanning Tunneling Microscopy. A high level of complexity is demonstrated to be needed for a dedicated theoretical model to adequately represent the specific features of quantum rings. The findings presented in this book contribute to develop low-cost high-performance electronic, spintronic, optoelectronic and information processing devices based on quantum rings.

  8. Design study of a resonant Schottky pick-up for the Rare-RI Ring project

    Energy Technology Data Exchange (ETDEWEB)

    Suzaki, F., E-mail: suzaki@ribf.riken.jp [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Zenihiro, J. [RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Yamaguchi, T., E-mail: yamaguti@phy.saitama-u.ac.jp [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Ozawa, A. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Uesaka, T.; Wakasugi, M.; Yamada, K.; Yamaguchi, Y. [RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)

    2013-12-15

    Highlights: • The heavy-ion storage ring project, the Rare-RI Ring, is ongoing at the RIKEN RI Beam Factory. • The Rare-RI Ring will enable precision isochronous mass spectrometry of r-process nuclei. • A resonant Schottky pick-up will be used for the precise tuning of isochronous optics of the storage ring. • Simulation results of 3D electromagnetic field calculations show a high sensitivity of stored single-ion detection. -- Abstract: The new heavy-ion storage ring project Rare-RI Ring at the RIKEN RI Beam Factory launched in 2012 aims at precision isochronous mass spectrometry for single ions of exotic nuclides. To precisely tune the storage-ring ion optical conditions to the isochronous field setting, Schottky noise pick-up technique will be employed. Pillbox-type resonant cavity, similar to the Schottky pick-up system successfully operating at the experimental storage ring ESR at GSI, is adopted for the pick-up probe. To determine the design values of the cavity, we systematically performed a simulation study of three-dimensional electromagnetic field calculations in the high frequency region. High shunt impedance obtained in the simulation will enable us to detect stored single ions with charge down to q≃15.

  9. Exploratory Research and Development Fund, FY 1990. Report on Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-01

    The Lawrence Berkeley Laboratory Exploratory R&D Fund FY 1990 report is compiled from annual reports submitted by principal investigators following the close of the fiscal year. This report describes the projects supported and summarizes their accomplishments. It constitutes a part of an Exploratory R&D Fund (ERF) planning and documentation process that includes an annual planning cycle, projection selection, implementation, and review. The research areas covered in this report are: Accelerator and fusion research; applied science; cell and molecular biology; chemical biodynamics; chemical sciences; earth sciences; engineering; information and computing sciences; materials sciences; nuclear science; physics and research medicine and radiation biophysics.

  10. Fun and games in Berkeley: the early years (1956-2013).

    Science.gov (United States)

    Tinoco, Ignacio

    2014-01-01

    Life at Berkeley for the past 57 years involved research on the thermodynamics, kinetics, and spectroscopic properties of RNA to better understand its structures, interactions, and functions. We (myself and all the graduate students and postdocs who shared in the fun) began with dinucleoside phosphates and slowly worked our way up to megadalton-sized RNA molecular motors. We used UV absorption, circular dichroism, circular intensity differential scattering, fluorescence, NMR, and single-molecule methods. We learned a lot and had fun doing it.

  11. Public census data on CD-ROM at Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Merrill, D.W.

    1992-07-02

    In connection with the Comprehensive Epidemiologic Data Resource (CEDR) and Populations at Risk to Environmental Pollution (PAREP) projects, of the Information and Computing Sciences Division (ICSD) at Lawrence Berkeley Laboratory (LBL), are using public socioeconomic and geographic data files which are available to CEDR and PAREP collaborators via LBL's computing network. At this time 67 CD-ROM diskettes (approximately 35 gigabytes) are on line via the Unix file server cedrcd.lbl.gov. Most of the files are from the US Bureau of the Census, and most pertain to the 1990 Census of Population and Housing. This paper contains a list of the CD-ROMs available.

  12. Public census data on CD-ROM at Lawrence Berkeley Laboratory. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Merrill, D.W.

    1992-07-02

    In connection with the Comprehensive Epidemiologic Data Resource (CEDR) and Populations at Risk to Environmental Pollution (PAREP) projects, of the Information and Computing Sciences Division (ICSD) at Lawrence Berkeley Laboratory (LBL), are using public socioeconomic and geographic data files which are available to CEDR and PAREP collaborators via LBL`s computing network. At this time 67 CD-ROM diskettes (approximately 35 gigabytes) are on line via the Unix file server cedrcd.lbl.gov. Most of the files are from the US Bureau of the Census, and most pertain to the 1990 Census of Population and Housing. This paper contains a list of the CD-ROMs available.

  13. Ring Around a Galaxy

    Science.gov (United States)

    1999-01-01

    Space Telescope Science Institute astronomers are giving the public chances to decide where to aim NASA's Hubble Space Telescope. Guided by 8,000 Internet voters, Hubble has already been used to take a close-up, multi-color picture of the most popular object from a list of candidates, the extraordinary 'polar-ring' galaxy NGC 4650A. Located about 130 million light-years away, NGC 4650A is one of only 100 known polar-ring galaxies. Their unusual disk-ring structure is not yet understood fully. One possibility is that polar rings are the remnants of colossal collisions between two galaxies sometime in the distant past, probably at least 1 billion years ago. What is left of one galaxy has become the rotating inner disk of old red stars in the center. Meanwhile, another smaller galaxy which ventured too close was probably severely damaged or destroyed. The bright bluish clumps, which are especially prominent in the outer parts of the ring, are regions containing luminous young stars, examples of stellar rebirth from the remnants of an ancient galactic disaster. The polar ring appears to be highly distorted. No regular spiral pattern stands out in the main part of the ring, and the presence of young stars below the main ring on one side and above on the other shows that the ring is warped and does not lie in one plane. Determining the typical ages of the stars in the polar ring is an initial goal of our Polar Ring Science Team that can provide a clue to the evolution of this unusual galaxy. The HST exposures were acquired by the Hubble Heritage Team, consisting of Keith Noll, Howard Bond, Carol Christian, Jayanne English, Lisa Frattare, Forrest Hamilton, Anne Kinney and Zolt Levay, and guest collaborators Jay Gallagher (University of Wisconsin-Madison), Lynn Matthews (National Radio Astronomy Observatory-Charlottesville), and Linda Sparke (University of Wisconsin-Madison).

  14. Environmental health-risk assessment for tritium releases at the National Tritium Labeling Facility at Lawrence Berkeley National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    McKone, T.E.; Brand, K.P. [Lawrence Livermore National Lab., CA (United States). Health and Ecological Assessment Div.; Shan, C. [Lawrence Berkeley National Lab., CA (United States). Earth Sciences Div.

    1997-04-01

    This risk assessment calculates the probability of experiencing health effects, including cancer incidence due to tritium exposure for three groups of people: (1) LBNL workers near the LBNL facility--Building 75--that uses tritium; (2) other workers at LBNL and nearby neighbors; and (3) people who use the UC Berkeley campus area, and some Berkeley residents. All of these groups share the same probability of health effects from the background radiation from natural sources in the Berkeley area environment, including an increased risk of developing a cancer of 11,000 chances per million. In calculating risk the authors assumed continuous operation in Building 75 for at least a human lifetime. Under this assumption, LBNL workers located near Building 75 have an additional risk of 60 chances out of one million to suffer a cancer; other workers at LBNL and people who live near LBNL have an additional risk of six chances out of one million over a lifetime of exposure; and users of the UC Berkeley campus area and other residents of Berkeley have an additional risk of less than once chance out of one million over a lifetime.

  15. Illustration of Saturn's Rings

    Science.gov (United States)

    2001-01-01

    This illustration shows a close-up of Saturn's rings. These rings are thought to have formed from material that was unable to form into a Moon because of tidal forces from Saturn, or from a Moon that was broken up by Saturn's tidal forces.

  16. Birth Control Ring

    Science.gov (United States)

    ... 5 of her menstrual cycle. It remains in place for 3 weeks in a row. At the end of the third week, on the same day of the week ... birth control until the ring has been in place for 7 days. If the ring is out for more than 3 hours during your third week wearing it, call your doctor to see ...

  17. Revocable Ring Signature

    Institute of Scientific and Technical Information of China (English)

    Dennis Y. W. Liu; Joseph K. Liu; Yi Mu; Willy Susilo; Duncan S. Wong

    2007-01-01

    Group signature allows the anonymity of a real signer in a group to be revoked by a trusted party called group manager. It also gives the group manager the absolute power of controlling the formation of the group. Ring signature, on the other hand, does not allow anyone to revoke the signer anonymity, while allowing the real signer to forma group (also known as a ring) arbitrarily without being controlled by any other party. In this paper, we propose a new variant for ring signature, called Revocable Ring Signature. The signature allows a real signer to form a ring arbitrarily while allowing a set of authorities to revoke the anonymity of the real signer. This new variant inherits the desirable properties from both group signature and ring signature in such a way that the real signer will be responsible for what it has signed as the anonymity is revocable by authorities while the real signer still has the freedom on ring formation. We provide a formal security model for revocable ring signature and propose an efficient construction which is proven secure under our security model.

  18. EBT ring physics

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, N.A. (ed.)

    1980-04-01

    This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers. (MOW)

  19. Steroidal contraceptive vaginal rings.

    Science.gov (United States)

    Sarkar, N N

    2003-06-01

    The development of steroid-releasing vaginal rings over the past three decades is reviewed to illustrate the role of this device as an effective hormonal contraceptive for women. Vaginal rings are made of polysiloxane rubber or ethylene-vinyl-acetate copolymer with an outer diameter of 54-60 mm and a cross-sectional diameter of 4-9.5 mm and contain progestogen only or a combination of progestogen and oestrogen. The soft flexible combined ring is inserted in the vagina for three weeks and removed for seven days to allow withdrawal bleeding. Progesterone/progestogen-only rings are kept in for varying periods and replaced without a ring-free period. Rings are in various stages of research and development but a few, such as NuvaRing, have reached the market in some countries. Women find this method easy to use, effective, well tolerated and acceptable with no serious side-effects. Though the contraceptive efficacy of these vaginal rings is high, acceptability is yet to be established.

  20. Algorithms for finite rings

    NARCIS (Netherlands)

    Ciocanea Teodorescu I.,

    2016-01-01

    In this thesis we are interested in describing algorithms that answer questions arising in ring and module theory. Our focus is on deterministic polynomial-time algorithms and rings and modules that are finite. The first main result of this thesis is a solution to the module isomorphism problem in