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MOYCH03 | Superconducting RF Cavities for Synchrotron Light Sources | damping, electron, insertion, synchrotron | 21 | ||||||
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Superconducting (sc) RF systems are already operational or planned in several third generation synchrotron light sources. In these machines, which require relatively low RF accelerating voltage and high beam loading, the advantage of using the sc technology essentially resides in the fact that one can achieve an efficient damping of the cavity Higher Order Modes (HOM) while still maintaining a high fundamental shunt impedance. The strong HOM damping practically is realised following two approaches : a) use of absorber material, located inside the cavity tube cut-off, through which the HOM propagate and then are damped (Cornell/KEK designs); b) two-cell cavity with coaxial HOM dampers located on the tube connecting the two cells (SOLEIL design). Third harmonic idle sc cavities (1.5 GHz) of the SOLEIL type are already operational in the Swiss Light Source and ELETTRA. The main RF system (500 MHz) of these machines consist of normal conducting cavities and the purpose of the third harmonic sc system is to lengthen the bunches in order to improve the beam lifetime and stability (additional Landau damping). Recently, several third generation synchrotron light sources have also planned to use sc cavities as main accelerating RF systems. The operational conditions of the existing systems as well as the status of the planned ones are reported here.
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MOPKF006 | Enhancements of Top-up Operation at the Swiss Light Source | injection, linac, controls, booster | 309 | ||||||
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Since the first experience on 2001, Top-Up is the standard mode of operation at the Swiss Light Source (SLS) for users. In order to fulfill the ongoing demands of machine experts and experiments we have had to add more functionality to the Top-Up mode thus make it more flexible. Some time-resolved experiments require a constant charge in a single isolated bucket in the gap of the normal filling of a bunch train of 80% of the circumference of the storage ring. Therefore the Hybrid application was developed that keeps the beam current distribution constant in this mode. We developed a maintenance mode too, to allow to work continuously on the Linac and booster - for example to optimize injection/extraction - without disturbing the Top-up for user operation. Even beam destructive experiments at the Linac during Top-Up or Hybrid operation are supported, where the Linac can be used synchronously at the times between successive refilling of the storage ring. The flexible control and timing systems at the SLS made these applications feasible. We describe the controls, operation and applications of each of the above functionalities in this paper.
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MOPKF025 | Planar and Planar Helical Superconductive Undulators for Storage Rings, State of the Art | undulator, vacuum, polarization, synchrotron | 354 | ||||||
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Planar superconductive undulators for low beam currents were successfully tested in the past. In a next step devices suitable for small gaps in storage rings are in preparation. The tests will clarify experimentally the heat load generated by the beam in the cold bore and will allow to optimize the control system of such devices. In addition, the layout of the next generation of planar superconductive undulators with electrically variable polarization direction are introduced in this paper.
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MOPKF034 | Status of the Development of Superconducting Undulators at the ESRF | undulator, vacuum, synchrotron, radiation | 378 | ||||||
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This note describes the present status of the development of superconducting undulators at the ESRF. Magnetic models of superconducting undulators suitable for the ESRF storage ring have been developed and evaluated. The superconducting undulators studied are horizontally polarizing undulators with a flat field profile and the vertical physical aperture of the undulator is 6 mm. Both 2D models of the local field in a period of the undulator and 3D models of the complete superconducting undulator, including the end sections and current leads, have been evaluated. The practical limit for the obtainable magnetic field has been estimated from the known performance of superconducting wire available from the cabling industry. This note also describes the conceptual design of the cryostat of the superconducting undulator and estimations of the expected heat load to the cryostat at different filling modes of the storage ring.
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MOPKF035 | Stabilization of the Pulsed Regimes on Storage Ring Free Electron Laser: The Cases of Super-ACO and Elettra | laser, feedback, electron, undulator | 381 | ||||||
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In a Storage Ring Free Electron Laser (SRFEL) a relativistic electron beam interacts with the magnetostatic periodic field of an undulator, thus emitting synchrotron radiation. The light is stored in an optical cavity and amplified during successive turns of the particles in the ring. The laser intensity may appear as a "continuous wave (cw)" or show a stable pulsed behaviour depending on the value of the temporal detuning, i.e. the difference between the electron beam revolution period and the round trip of the photons in the cavity. It was recently shown, that the loss of stability in a SRFEL occurs through an Hopf bifurcation [*]. This observation opens up the perspective of introducing a derivative self-controlled feedback to suppress locally the bifurcation and enlarge the region of stable signal. A feedback of this type has been implemented on Super-ACO and shown to produce a significant and reproducible extension of the stable "cw" region. We review here these results and discuss new experiments performed on the Super-ACO and ELETTRA SRFELs.
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* G. De Ninno and D. Fanelli, Phys. Rev. Lett. in press; M.E. Couprie et al. Nucl. Instrum.and Meth. A., in press |
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MOPKF040 | Effect of Electron-beam Feedbacks on the ELETTRA Storage-ring Free-electron Laser | feedback, laser, free-electron-laser, electron | 393 | ||||||
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As is well known, the stability of a storage-ring free-electron laser is strongly related to that of the electron beam. With respect to second-generation devices, such as Super ACO and UVSOR, the free-electron laser at ELETTRA is characterized by a noticeably higher gain and, consequently, shows to be much more sensitive to electron-beam instabilities. In order to counteract the impact of such instabilities, both a longitudinal multibunch and a local orbit feedbacks have been implemented for free-electron laser operation. Aim of this paper is to report on the beneficial effect of these feedback systems on the laser performance.
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MOPKF047 | Suppression of Stored Beam Oscillation Excited by Beam Injection | injection, sextupole, synchrotron, optics | 414 | ||||||
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Top-up operation is scheduled from May 2004 at SPring-8. For this operation it is important that frequent beam injections should not excite the oscillation of stored beams. However, injection bump orbit was not closed perfectly and residual beam oscillations lead to increase of effective beam sizes by twice and three times in the horizontal and vertical direction respectively. We are trying to reduce these excited oscillations to less than one third of the usual beam sizes. For the suppression of horizontal one, we applied a novel scheme to reduce the effect due to the nonlinearity of sextupole magnets by adjusting the strength ratio of the sextupoles. The field similarity of bump magnets was also improved by replacing them with newly designed ones, where the effect of eddy current at the end plates was reduced. These countermeasures suppressed the horizontal oscillation by about one order. For the suppression of vertical one, the excitation mechanism has being investigated in detail. Presently the tilt angle adjustment of bump magnets reduced the vertical oscillation by one third. For further reduction of these oscillations, corrections with pulse-magnets is under investigation.
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MOPKF048 | Injection Beam Loss at the SPring-8 Storage Ring | undulator, betatron, simulation, injection | 417 | ||||||
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Capture efficiency of injection beam is extremely important for top-up operation because open photon shutter permits the bremsstrahlung from lost particles to be transported to experimental floor. Furthermore, since the SPring-8 storage ring has many in-vacuum insertion devices with narrow gap, the demagnetization by the lost electron bombardment is also serious to the beam injection with gap closing. To clarify the loss mechanism of injected beam at the SPring-8 storage ring, we investigate the loss process under various conditions of the storage ring, and especially measure the dependence of injection loss rate on gaps of insertion devices. Comparing the measurements with simulations, we found that an injected particle with a large horizontal amplitude begins to oscillate in vertical direction through error magnetic field and eventually disappears at the vertical limit. It is also found that the low chromaticity of the storage ring is effective for the reduction of injection beam loss. In this paper, we report the loss mechanism of the injection beam of the SPring-8 storage ring and the possible improvements of the capture efficiency.
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MOPKF052 | Design of an In Archromatic Superconducting Wiggler at NSRRC | wiggler, vacuum, synchrotron, multipole | 425 | ||||||
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A 15-pole superconducting wiggler with period length of 6 cm is designed for National Synchrotron Research Center (NSRRC) in Taiwan. The compact superconducting wiggler will be installed near the second bending magnet of the triple bend achromat section in the 1.5 GeV storage ring. This wiggler magnet with maximum peak field of 3.2 T at pole gap width of 19 mm is operated in 4.2 K liquid helium vessel. A 5-pole prototype magnet is tested and measured to verify the magnetic field performance in the testing dewar. Furthermore, the cryogenic considerations and thermal analysis in the 4.2 K wiggler magnet and the 77 K vacuum chamber are also presented in this work.
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MOPKF068 | Experimental Study of the Stability Margin with Beam Heating in a Short-Period Superconducting Undulator for the APS | vacuum, undulator, photon, synchrotron | 470 | ||||||
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A superconducting undulator with a period of 15 mm is under development at the Advanced Photon Source (APS). The undulator is designed to achieve a peak field on the beam axis of 0.8 T with an 8 mm pole tip gap and an NbTi coilpack current density of 1 kA/mm2. Because of the high current density in the coilpack, the superconducting magnet operates at about 75% of the short sample limit at 4.2K. Additional heat load to the coilpack, mainly due to the image currents and synchrotron radiation from the electron beam in the storage ring, will reduce the stability margin. An experiment was conducted to measure the reduction in the stability margin of the coilpack due to heat load on the beam chamber. The heat load was deposited in a 12-period prototype undulator using thin-film heaters attached to the inner surface of a simulated vacuum chamber. Evaluation of the stability margin based on the experiment and calculations of the beam heating and thermal conduction between the undulator and beam chamber will be discussed.
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MOPLT041 | Production of Superconducting Accelerator Modules for High Current Electron Storage Rings | vacuum, instrumentation, electron, damping | 638 | ||||||
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For Diamond Light Source, ACCEL was awarded to produce three more superconducting 500 MHz accelerator modules of the Cornell CESR design. With the already 6 modules produced for Cornell, NSRRC and CLS, this module can now be considered as a kind of standard product. In this paper we describe the basic parameters and guaranteed values of this module and will also report on the performance of delivered modules.
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MOPLT053 | On Parasitic Crossings and their Limitations to e+e- Storage Ring Colliders | luminosity, beam-beam-effects, factory, collider | 671 | ||||||
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We treat the problem of parasitic crossing in e+e- storage ring colliders analytically. Analytical formulae for the beam lifetime limited by the combined effects of beam-beam interactions at interaction point and at parasitic crossings are derived, and applied to the by-2 colliding mode of PEP-II low energy ring.
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MOPLT086 | Upgrading the Control System at KCSR | monitoring, vacuum, radiation, power-supply | 734 | ||||||
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Till now Kurchatov Centre of Synchrotron Radiation facility control system is based on a CAMAC-oriented computers network. In this paper the project of upgrading and results of prototyping of the new equipment is submitted. Upgrading includes two levels. First, it is possible to create the modern CAMAC crate-controller, connected with standard network. More advanced variant will consist in replacement of CAMAC modules with the embedded controllers of equipment. Second level is a creation of a local managing network of personal computers, as consoles of the control system. The control system is functionally divided into four levels: 1) the controllers managing in a real-time mode by the executive equipment; 2) the workstations which are supporting the link with controllers by CAN-network; 3) the server of applications containing a dynamic database; 4) the PCs network for users applications. Examples of realisation of the software are presented.
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MOPLT090 | High Pulse and Average Power Low-induction Load | injection, damping, linac, extraction | 746 | ||||||
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A high pulse and average power low-induction load with a built-in divider is described in this report. The load has a nominal resistance of 25 Ohm and is designed to operate with a repetition rate of up to 50 Hz at a pulse duration (FWHM) of 100 ns, a rise/fall time of 50 ns and a pulse amplitude of up to 40 kV. In this mode the dissipated energy is equal to about 8 J per pulse and average power is up to 400 W. The load can be used as an absorbing load and as a block element in high-voltage engineering.
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MOPLT092 | Single Mode RF Cavity for VEPP-2000 Storage Ring Based Collider | coupling, damping, impedance, luminosity | 752 | ||||||
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Accelerating cavity 172 MHz with strong damped higher-order modes (HOM) for VEPP-2000 electron-positron collider have been made in Novosibirsk. Resonance frequences and Q values of cavity HOMs are measured and analysed. Most of HOMs have Q values less than 300. We compare these results with computer calculations of HOM.
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MOPLT100 | Magnetic Structure of the NSC KIPT Nuclear-and-high-energy-physics Electron Accelerator | electron, injection, quadrupole, dipole | 764 | ||||||
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Design options of the magnetic structure of a new proposed accelerator facility at NSC KIPT with a continuous-wave electron beam are described. The accelerator represents a recirculator, based on standard TESLA superconducting accelerating sections in one or two straight sections with a length of 5 or 19 meters. The magnetic system is designed on the basis of the magnetic elements of storage ring EUTERPE, transferred by Eindhoven University to NSC KIPT. The focusing and dispersion functions for several design choices of the magnetic structure are reported. Modeling of the beam movement in the accelerator has been carried out; the beam parameters during acceleration and on accelerator output have been calculated.
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MOPLT109 | Longitudinal Schottky Spectra of Bunched Beams | synchrotron, antiproton, proton, diagnostics | 791 | ||||||
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In this paper we derive an expression for longitudinal Schottky spectrum of a bunched beam in a stationary bucket. The expression is then used to calculate longitudinal emittance of the antiproton beam in the Fermilab Recycler ring. The Recycler beam is bunched longitudinally by a barrier-bucket rf waveform. Under certain bucket conditions, dependence of synchrotron frequency on particle energy becomes non-monotonic. It complicates the Schottky spectrum derivation and interpretation; we address these difficulties in our paper.
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MOPLT147 | SPEAR 3 Commissioning Software | optics, simulation, insertion, insertion-device | 884 | ||||||
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In order to meet the tight SPEAR 3 accelerator commissioning schedule, a software package was assembled to streamline experimental measurements and data analysis. At the heart of the software is a MATLAB "middle layer" with an element definition database and channel access link for fast and easy communication with the EPICS control system. Originally adapted from work at the ALS, the middle layer allows direct control from the MATLAB command line, use in the form of short "scripts" for specific experiments and integration into high-level application programs. The revised software is also machine-independent. This paper outlines the software architecture and provide examples with results from the SPEAR 3 accelerator commissioning effort.
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MOPLT171 | A Pratical Demonstration of the CRFQ Storage Ring | rfq, focusing, proton, injection | 926 | ||||||
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The Circular Radiofrequency Quadrupole (CRFQ) is a new concept of a storage and accelerator ring for intense beams of light and heavy ions, protons and electrons. It is basically a Linear Radio-Frequency Quadrupole completely bent on a circle. The advantages are expected to be equivalent to those of a Linear RFQ, namely higher beam intensity and smaller beam dimensions. Moreover, it is a more compact device when compared to conventional accelerators. A collaboration was created between Brookhaven National Laboratory, the University of Naples, the University of Sannio, and the INFN-Section of Naples (Italy) for the purpose of developing a proof of principle (PoP) of the CRFQ. During the initial stage the main goal is the demonstration of the curvature effect of the quadrupolar RFQ field. At that purpose, the project is actually conceived of three phases: (i) develop an adequate 30 keV proton source, (ii) design, manufacture and test a linear RFQ section, and (iii) design, manufacture and test a curved RFQ section, both operating at 200 MHz. The linear section acts as a matching with the ion source at one end, and the curved section at the other. The paper discusses mechanical and RF considerations during the design and experiment. The final goal of the collaboration is eventually to build enough curved sections to complete the storage ring where to demonstrate storage of 30 keV protons over long periods of time.
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TUPKF001 | Upgrade and Commissioning of the LNLS RF System | klystron, synchrotron, damping, feedback | 950 | ||||||
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In this paper we present a report on the commissioning of the new RF system of the electron storage ring of the brazilian synchrotron radiation facility (LNLS).
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TUPKF020 | Numerical Investigation on the ELETTRA 500 MHz Power Coupler | vacuum, coupling, simulation, electron | 1006 | ||||||
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Due to the high input power required to feed a resonant cavity, the RF input coupler is a critical component for the reliability of an RF system. The 500 MHz RF input coupler for the ELETTRA cavities was specified for 150 kW input power. It is important to investigate the performance limits of the coupler in view of increasing RF power requirements. The coupler's maximum peak field and dissipation versus the input power have been studied by means of the numerical simulator HFSS. Possible improvements to the existing design have been investigated. The optimization has to take into consideration the following requirements: convenient power transmission efficiency, RF matching, suitable coupling coefficient, negligible perturbation on cavity voltage, moderate operating temperature and stress.
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TUPKF021 | First Year of Operation of SUPER-3HC at ELETTRA | damping, vacuum, electron, synchrotron | 1009 | ||||||
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Since July 2003 a superconducting third harmonic cavity has been in routine operation at ELETTRA. When the cavity is activated the stored electron bunches are lengthened by about a factor of three. The related longitudinal Landau damping has allowed first time operation at 320 mA, 2.0 GeV with a beam completely free of longitudinal coupled bunch instabilities. With the cavity active the lifetime at 320 mA, 2.0 GeV is three times the theoretical value for nominal bunch length. The increase in beam stability and lifetime contributed significantly to enhance the brightness and the integrated flux of the source. We will further discuss the operating experience with the superconducting cavity and the cryogenic system, analyzing the impact of the new system on machine operation and uptime. Finally we will also report on the characterization of the cavity performance for different filling patterns of the storage ring and relate the results to preliminary beam-cavity interaction studies.
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TUPKF038 | Reduced Length Designs of 500 MHz Damped Cavity Using SiC Microwave Absorber | undulator, impedance, synchrotron, factory | 1048 | ||||||
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We present a new 500 MHz HOM (Higher-Order Modes) damped cavity for high brilliance synchrotron radiation sources. The design is based on the damped cavity, which is operated at the Photon Factory storage ring in KEK. The PF cavity has a large hole beam duct (140 mm in diameter), a part of which is made of a silicon carbide (SiC) microwave absorber. The new cavity, proposed in this paper, has parallel-plate radial transmission lines on the beam duct instead of the SiC beam duct. The outer end of the radial line is terminated by SiC absorbers. The HOMs, extracted from the center part of the cavity through the beam duct, propagate in the radial line and are dissipated in the absorber. The accelerating mode is not affected by the radial line damper since the frequency is sufficiently below the cutoff of the 140-mm beam duct. In this paper, optimized design of the radial line damper and damping properties for HOMs are described in detail.
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TUPKF039 | The Experiences of Operation and Performance about the 500 MHz CW Klystrons at the PLS Storage Ring | klystron, electron, coupling, cathode | 1051 | ||||||
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There are four RF stations to supply the energy to electron at the storage ring of the Pohang Light Source(PLS). From the beginning of the operation of RF system, 500MHz 60kW(CW) klystrons have been operated. As the operation time of the tubes are increased, their performances are decreased. Therefore three 60kW tubes were replaced with the same model and two 75kW klystrons were replaced with 60 kW klystrons so far. Nowadays two 75 kW and two 60 kW klystrons are operated in the RF system of PLS. Our experiences of the klystron operation and their general performance are described in this paper.
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TUPKF053 | New Waveguide-type HOM Damper for the ALS Storage Ring RF Cavities | damping, vacuum, radiation, synchrotron | 1069 | ||||||
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The ALS storage ring 500 MHz RF system uses two re-entrant accelerating cavities powered by a single 320kW PHILLIPS YK1305 klystron. During several years of initial operation, the RF cavities were not equipped with effective passive HOM damper systems. Longitudinal beam stability was achieved through cavity temperature control and the longitudinal feedback system (LFB), which was often operating at the edge of its capabilities. As a result, longitudinal beam stability was a significant operations issue at the ALS. During two consecutive shutdown periods (April 2002 and 2003) we installed E-type HOM dampers on the main and third harmonic cavities. These devices dramatically decreased the Q-values of the longitudinal anti-symmetric HOM modes. The next step is to damp the rest of the longitudinal HOM modes in the main cavities below the synchrotron radiation damping level. This will hopefully eliminate the need for the LFB and set the stage for a possible increase in beam current. The ?waveguide? type of HOM damper was the only option that didn?t significantly compromise the vacuum performance of the RF cavity. The design process and the results of the low level measurements of the new waveguide dampers are presented in this paper.
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TUPLT003 | Transfer Matrices for the Coupled Space Charge Dominated Six-dimensional Particle Motion | space-charge, lattice, coupling, electron | 1135 | ||||||
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In this paper we present exact analytical solutions for the particle motion in the six-dimensional phase space taking into account the space charge forces of fully linear coupled beam. The transfer matrices for the typical elements of magnetic lattice, such as drifts, cavities, quadrupole and dipole magnets have been obtained. The symplectic transfer matrices are used to develop a tracking program for the coupled betatron and synchro-betatron motion that enables the simulation of the tilted beam effects in circular accelerators.
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TUPLT013 | Calculating LHC Tuning Knobs using Various Methods | quadrupole, lattice, optics, closed-orbit | 1159 | ||||||
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By measuring and adjusting the beta-functions at the IP the luminosity is being optimized. In LEP this was done with the two closest doublet magnets. This approach is not applicable for the LHC due to the asymmetric lattice and common beam pipe through the triplet magnets. To control and change the beta-functions quadrupole groups situated on both sides further away from the IP have to be used where the two beams are already separated. The quadrupoles are excited in specific linear combinations, forming the so-called tuning knobs for the IP beta-functions. We compare the performance of such knobs calculated by different methods: (1) matching in MAD, (2) inversion of the re-sponse matrix and singular value decomposition inversion and conditioning and (3) conditioning the response matrix by multidimensional minimization using Hessian method.
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TUPLT016 | Improved Performance of the Heavy Ion Storage Ring ESR | electron, ion, injection, heavy-ion | 1168 | ||||||
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The heavy ion storage ring ESR at GSI allows experiments with stable and radioactive heavy ions over a large range of energies. The energy range available for operation with completely stripped ions has recently been extended to energies as low as 3 MeV/u. Even for bare uranium such low energies can be provided by deceleration of the ions which are stripped to high charge states in a foil at energies of 300-400 MeV/u. After injection the beam is cooled and decelerated in an inverse synchrotron mode interspersed with electron cooling at an intermediate energy. At the lowest energy of 3 MeV/u some hundreds of thousands ions could be electron cooled after deceleration. At energies of 10-20 MeV/u physics experiments with stored and slowly extracted beam have been performed with some million decelerated cooled ions. The cooling of radioactive ions by a combination of stochastic pre-cooling and final electron cooling has been demonstrated. The hot fragment beam, which was injected at an energy of 400 MeV/u, was cooled in about 6 s to a quality useful for precision experiments.
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TUPLT018 | Layout of the Storage Ring Complex of the International Accelerator Facility for Research with Ions and Antiprotons at GSI | antiproton, ion, electron, target | 1174 | ||||||
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The storage ring complex of the new international accelerator facility consists of three different rings: the Collector Ring CR, the accumulator/decelerator ring RESR and the New Experimental Storage Ring NESR. The CR will serve for fast stochastic precooling of antiproton and rare isotope (RI) beams. Cooling time constants of about 100 ms for RI beams are envisaged. For experiments with RI beams the RESR serves as a decelerator ring. Precooled RI beams will be injected at 740 MeV/u and then decelerated to variable energies down to 100 MeV/u within about 1 s. The NESR will be the main instrument for nuclear and atomic physics. Besides experiments using an internal gas target, the NESR offers the possibility to collide circulating bunches of ions with electron bunches counter-propagating in a small 500 MeV electron storage ring. The physics program with antiprotons requires the accumulation of high intensity antiproton beams. The accumulation of 7×1010 antiprotons at 3 GeV per hour is foreseen. This will be accomplished by operating the RESR as an accumulator ring equipped with a stochastic cooling system. The NESR could then be used to decelerate antiprotons to 30 MeV.
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TUPLT039 | An Electrostatic Quadrupole Doublet with an Integrated Steerer | quadrupole, ion, focusing, coupling | 1234 | ||||||
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Electrostatic storage rings have proven to be a valuable tool for atomic and molecular physics Due to the mass independence of the fields in the bending and focusing elements, different kinds of ions with the same charge/energy ratio from light protons to very heavy biomolecules, can be stored with the same field setup. The transverse dimensions of the circulating beam are controlled by electrostatic quadrupole doublets or triplets. It is essential that the fields in these lenses can be adjusted independently one from another to allow an exact control of the stored ions. In this paper, first an overview of the principle of electrostatic lenses is given. After a short discussion of fringe field effects, the results of field calculations are presented and the final layout of an electrostatic quadrupole doublet with an integrated steerer as it will be used in future electrostatic storage rings in Frankfurt and Heidelberg is discussed.
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TUPLT040 | CSR - a Cryogenic Storage Ring at MPI-K | ion, electron, vacuum, quadrupole | 1237 | ||||||
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A small cryogenic storage ring is planned to be developed at MPI-K, Heidelberg. The energy in the machine will be variable from 300 keV > down to 20 keV. Electron cooling will be applied to produce a high quality ion beam. The ring shall accommodate slow, vibrationally and rotationally cooled molecular ions and highly charged ions from the EBIT ion source. Moreover, it will serve as a test facility for the low-energy antiproton ring planned within the FLAIR collaboration to be installed at the future GSI facility. A number of technological challenges have to be handled: Especially highly charged ions require a vacuum in the order below 10-13 mbar to achieve reasonable lifetimes. Therefore - and for enabling experiments with rotationally cold molecules - the complete machine will be cooled down to below 10 K. Moreover, experiments with reaction microscopes to determine the full kinematics of ion- (antiproton-) atom or molecule collisions require a bunched operation with a bunch length below 2 ns. The optical elements of the machine and the lattice functions are given and first ideas about the vacuum chamber design are described in this paper.
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TUPLT041 | Ultra-low Energy Antiprotons at FLAIR | antiproton, electron, ion, injection | 1240 | ||||||
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The Future Accelerator Facility for Beams of Ions and Antiprotons at Darmstadt will produce the highest flux of antiprotons in the world. So far it is foreseen to accelerate the antiprotons to high energies (3-15 GeV) for meson spectroscopy and other nuclear and particle physics experiments in the HESR (High Energy Storage Ring). Within the planned complex of storage rings, it is possible to decelerate the antiprotons to about 30 MeV kinetic energy, opening up the possibility to create low energy antiprotons. In the proposed FLAIR facility the antiprotons shall be slowed down in a last step from 300 keV to 20 keV in an electrostatic storage ring (USR) for various in-ring experiments as well as for their efficient injection into traps. In this energy range - especially if one thinks about realizing a real multi-purpose facility with not only antiprotons, but also various highly-charged radioactive ions to be stored and investigated - electrostatic storage rings have clear advantages compared to their magnetic counterparts. In case one envisions to even approach the eV range, electrostatic machines are the only possible choice. This contribution presents the layout and design parameters of the USR.
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TUPLT042 | Ring of FIRE | ion, quadrupole, injection, lattice | 1243 | ||||||
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A small electrostatic storage ring is the central machine of the Frankfurt Ion stoRage Experiments which will be build up at the new Stern-Gerlach-Center of Frankfurt university. With ion energies up to 50 keV it will allow new methods to analyze complex many-particle systems from atoms to very large bio molecules. The high luminosity of the beam allows measurements with many orders of magnitude better resolution compared to traditional measurements. It will be combined with existing experiments, like the reaction microscope COLTRIMS and the ECR ion source. In comparison to earlier designs, the ring lattice was modified in many details: Problems in earlier designs were related with e.g. the detection of light particles and highly charged ions with different charge states. Therefore, the deflectors were redesigned completely, allowing a more flexible positioning of the diagnostics. In this contribution the final design of the storage ring is presented and the layout of all elements given. First results from vacuum measurements in the recently assembled quarter ring section are summarized.
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TUPLT059 | Evolution of Optical Asymmetries in the Elettra Storage Ring | quadrupole, betatron, optics, sextupole | 1288 | ||||||
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Optical asymmetries have been measured and analyzed, before and after the magnet realignments. One way is to compare theoretical to measured orbit response matrices. Another way is to analyze the measured response matrix itself, by comparing the measured effects at identical optical positions. To evaluate the effects of the sextupoles on the optical asymmetries, the measurements have been performed with the sextupoles ON and OFF. The impact of a partial realignment is also analyzed both by varying the quadrupole excitations as well as by performing dispersion and coupling measurements. The results are presented in this paper.
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TUPLT074 | Dark Current Reduction System for SPring-8 Linac | linac, single-bunch, gun, synchrotron | 1324 | ||||||
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The SPring-8 linac accelerates dark currents generated by its injector part up to 1 GeV. These dark currents are injected with main beam into the SPring-8 storage ring and then spoil the purity of the stored beam. The dark currents are mainly composed of a grid emission current from a thermionic gun and field emission currents from rf accelerating structures. A beam deflector for kicking only the grid emission by a pulsed electric field was developed and installed in the SPring-8 linac. We observed that the beam deflector greatly reduced the grid emission current accelerated up to 1 GeV. The measured purity of the stored single-bunched beam was about 5x10-6 when the deflector operated, which was almost 1/100 of the purity without filtering by the deflector. However, the deflector, which is installed before the prebucher, cannot reduced the field emission currents from the buncher cavities and the first acccelerating structure. These dark currents take considerable proportion of the total dark currents observed at the end of the linac. We are trying to spin off the field emission currents by weak magnetic fields across the accelerating structure generated by several coils.
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TUPLT076 | Optimization of Sextupole Strengths in a Storage Ring for Top-up Operation | sextupole, injection, optics, synchrotron | 1330 | ||||||
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In top-up operation of a light source, electron or positron beams are frequently injected to keep the stored current constant. Closing an injection bump orbit is thus critically important not to disturb precise experiments. However, there are sextupole magnets inside the injection bump in the SPring-8 storage ring and the bump never closes all over the bump amplitude due to the sextupole nonlinearity. To solve the problem, we proposed a scheme based on minimum condition for the injection bump leakage. The scheme only restricts the sextupole strengths within the bump. Introduction of other sextupole families outside the bump can enlarge the dynamic aperture (DA) of the ring with keeping the minimum leakage. To find the best solution, we optimized the sextupole strengths changing the number of sextupole family as a parameter. The simulation shows that addition of two sextupole families sufficiently enlarges DA. Cabling of the sextupole magnets was partly changed in the summer 2003 and the effects of the strength optimization on the bump leakage, injection efficiency and beam lifetime has been investigated experimentally. We present the obtained results compared with the simulations.
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TUPLT087 | Deflection Element for S-LSR | ion, quadrupole, lattice, dipole | 1357 | ||||||
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Main lattice of the ion storage and cooler ring, S-LSR is composed of 6 dipole and 12 quadrupole magnets. The maximum magnetic field, the radius of curvature and gap height are 0.95 T, 1050 mm and 70 mm, respectively. The field measurement of the dipole magnets has been completed with use of Hall-probe position controlled by driving mechanism composed of stepping motors and ball-screws. In order to cancel out the momentum dispersion, the radial electric field is superposed with the magnetic field. The radial electric field is applied by the electrodes installed into the vacuum vessel set inside the rather limited gap of the dipole magnet. Good field quality is to be realized with use of intermediate electrodes. In the present paper, the results of the magnetic field measurements are presented together with the design of the superposed electric field.
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TUPLT099 | A Kicker Pulse Power Supply with Low Jitter | kicker, power-supply, injection, booster | 1387 | ||||||
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The performance of kicker pulse power supplies is the main parameter to increase injection efficiency of storage ring that is an important issue for laboratory of synchrotron radiation research. The output current waveform of a kicker pulse power supply with low timing jitter is our goal for years that must satisfy the Top-Up mode injection requirement of NSRRC. In the past years kicker pulse power supplies of storage ring of NSRRC are immersed in isolation oil to sustain high voltage operational environment that led difficult to maintain, electronic component degrading and uneasy to tune parameters. Air-cooling and air-isolation is adopted in the new design structure for kicker pulse power supply system and an pre-trigger unit MA2709A is installed to trigger thyratron tube CX1536A, a kicker pulse power supply with low timing jitter 1~2ns(p-p) is obtained and could satisfy for Top-Up mode injection and maintenance is more easier than before.
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TUPLT124 | DESIREE - A Double Electrostatic Storage Ring | ion, vacuum, quadrupole, ion-source | 1425 | ||||||
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The advantages of storage rings with only electrostatic elements were first demonstrated by ELISA in Aarhus and later in other places. At MSL and Fysikum at Stockholm University the ideas have been developed further in the Double Electrostatic Storage Ion Ring ExpEriment, DESIREE. Beams of negative and positive ions will be merged in a common straight section of the rings so that low energy collisions can be studied. Furthermore the rings will be cooled to 10 - 20 K in order to relax internal excitations in circulating molecules. A design report can be found at www.msl.se. The project is now (January 2004) almost fully financed and the final design work has recently been started. The paper will shortly review the physics programme and describe the status of the design work.
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TUPLT128 | The Operation Modes of Kharkov X-ray Generator based on Compton Scattering NESTOR | electron, laser, photon, scattering | 1428 | ||||||
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The results of theoretical and numerical considerations of linear Compton scattering are used to evaluate characteristics of X-rays produced by collision between a low emittance electron beam and intensive laser light in an X-rays generator NESTOR of NSC KIPT. Two main generation modes have been under consideration at preliminary NESTOR design. There are the operation mode for medicine 33.4 keV X-rays production using 43 Mev electron beam and Nd:YAG laser beam and higher energy X-rays production mode providing X-rays with energy up to 900 keV with 225 MeV electron beam and Nd:YAG laser beam. It is supposed to use an optical cavity for laser beam accumulation of about 2.6 m long and an interaction angle of about 30 in both operation modes. A few more operation modes provide possibility to expand operation range of NESTOR. Using interaction angle 100 and 1500 along with optical resonator 42 or 21 cm long and the second mode of laser light it is possible to produce X-rays in energy range from a few keV till 1.5 MeV. The intensity and spectral brightness of the X-rays is expected to be ~ 1013 phot/s and ~ 1013 phot/s/mm2/mrad2/0.01%BW respectively.
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TUPLT129 | NESTOR Reference Orbit Correction | electron, pick-up, laser, radiation | 1431 | ||||||
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It is known that intensity of scattered radiation in X-rays generators based on Compton scattering strongly depends on relative position of electron and laser beams. For this reason it is very important to have effective system of reference orbit correction and beam position control as well along whole ring as at the interaction point. In the paper the results of design and development of reference orbit correction system for compact storage ring NESTOR are presented. The total reference orbit correction will be carried out in vertical plane only. Correctors will be disposed on quadrupole lenses and will be provide reference orbit correction angle up to 0.10. The local correction at the interaction point will be provided with four correctors located at the interaction straight section. In the article results of calculations, layout of whole system, quadrupole lenses and pick-up station parameters and schemes are presented.
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TUPLT132 | Investigation of Injection through Bending Magnet Fringe Fields in X-rays Source NESTOR | injection, dipole, linac, vacuum | 1434 | ||||||
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In paper injection in the X-rays source NESTOR through fringe fields of a bending magnet is considered. The simulation of a motion of a beam of charged particles through 3-d fields of magnetic devices of the injection channel, which ones is located on a ring, are performed. The focusing properties of the injection channel are determined.
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TUPLT134 | Lattice of NSC KIPT Compact Intense X-ray Generator NESTOR | electron, lattice, laser, sextupole | 1440 | ||||||
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The new generation of the intense X-rays sources based on low energy electron storage ring and Compton scattering of laser beam allows to produce X-rays with intensity up to 1014 phot/s. One of the main traits of a storage ring lattice for such generator type is using of magnetic elements with combined focusing functions such as bending magnets with quadrupole and sextupole field components. In combination with very low bending radius and dense magnetic elements setting along ring circumference it leads to increasing of 3D magnetic field effects on electron beam dynamics and can decrease generated radiation intensity drastically. For the reasons of very low electron beam size at the interaction point and strong focusing in a compact storage ring the questions of determination of accuracy of bending magnet is very important too. The paper is devoted to the description of lattice of NSC KIPT Compact X-ray generator NESTOR. The results of investigations of the effects of 3D magnetic field and harmonic compound due to manufacture errors of bending magnets, bending magnet and lenses edges on electron beam dynamics are presented.
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TUPLT146 | Techniques to Extract Physical Modes in Model-independent Analysis of Rings | betatron, synchrotron, coupling, simulation | 1473 | ||||||
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SVD mode analysis is a basic techinique in Model-Independent Analysis of beam dynamics. It decomposes the spatial-temporal variation of a beam centroid into a small set of orthogonal modes based on statistical analysis. Although such modes have been proven to be rather informative, each orthogonal mode may not correspond to an individual physical source but a mix of several in order to be orthogonal. Such mixing makes it difficult to quantitatively understand the SVD modes and thus limits their usefulness. Here we report a new techinique to untangle the mixed modes in storage ring analysis based on the fact that most of the physical modes in a ring have identifiable characteristics in frequency domain.
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TUPLT161 | Normal Form Analysis of Linear Beam Dynamics in a Coupled Storage Ring | lattice, coupling, betatron, emittance | 1503 | ||||||
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The techniques of normal form analysis, well known in the literature, can be used to provide a straightforward characterization of linear betatron dynamics in a coupled lattice. Here, we consider both the beam distribution and the betatron oscillations in a storage ring. We find that the beta functions for uncoupled motion generalize in a simple way to the coupled case. Defined in the way that we propose, the beta functions remain well behaved (positive and finite) under all circumstances, and have essentially the same physical significance for the beam size and betatron oscillations as in the uncoupled case. Application of this analysis to the online modeling of the PEP-II rings is also discussed.
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WEYCH01 | Fast Pulsed SC Magnets | dipole, synchrotron, ion, antiproton | 132 | ||||||
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The demand for high beam intensities leads to the requirement of fast pulsed magnets for synchrotrons. An example is the proposed 'International Facility for Beams of Ions and Antiprotons' at GSI, which will consist of two synchrotrons in one tunnel and several storage rings. The high field ramp rate and repetition frequency introduce many magnet design problems and constraints in the operation of the accelerator. Persistent currents in the superconductor and eddy currents in wire, cable, iron and vacuum chamber reduce the field quality and generate cryogenic losses. Due to the large number of magnet cycles during the lifetime of such a magnet, special attention has to be paid to magnet material fatigue problems. The large charging voltages put some constraints on the use of cold diodes for quench protection. R&D has started at GSI, in collaboration with many institutions, to comply with the constraints mentioned above. Model dipoles were built and tested. The results of the R&D are reported. The advantages of the use of low field, fast pulsed superconducting, compared to resistive, magnets will be discussed
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WEILH04 | Industrial Involvement in the Construction of Synchrotron Light Sources | synchrotron, booster, vacuum, insertion | 206 | ||||||
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The design, construction and commissioning of a modern third-generation synchrotron light source facility is a major project, costing hundreds of millions of dollars. The delivery of these new facilities, usually on a fixed budget and schedule, requires an effective working relationship with all suppliers providing equipment and services to the project. This talk will examine some of the key issues in developing and maintaining such a relationship with industry during the construction of a third-generation synchrotron light facility. These issues include project planning, the contract specification, the tendering process, communication techniques over the contract term, and other aspects of contract control. Examples, primarily from our experience constructing the Canadian Light Source but also from other new facilities planned or under construction, will be used to examine the effectiveness of various approaches to working with industry.
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WEPKF005 | Pressure Field Distribution in a Cylindrical Geometry with Arbitrary Cross Section | vacuum, electron | 1597 | ||||||
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This work presents analytical and numerical results for the pressure field distribution along the axis of tubular geometries with arbitrary axisymmetric cross sections with an arbitrary time- and position-dependent gas source. Several areas of applied physics deal with problems in high-vacuum and ultra high-vacuum technology that present tubular form. In many cases one finds tubes with non uniform cross sections, like parts of particle accelerators, colliders, storage rings, gravitational antennas, and electron devices, like klystrons, electron microscopes, and also parts of vacuum systems in general, for instance, bellows, conical pipes and others. In this work one can get the detailed pressure distribution is not determined. This work presents and describes in detail the pressure field in tubes with arbitrary axisymetric cross sections. Details of the mathematical and physical formulations and modeling are given; specific conductance and specific throughput are defined; and a detailed discussion about the boundary conditions is given. These concepts and approach are applied to usual realistic cases, like conical tubes and bellows, with typical laboratory dimensions.
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WEPKF025 | Experience with the Hydrostatic Levelling System of the SLS | alignment, monitoring, synchrotron, synchrotron-radiation | 1651 | ||||||
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The Hydrostatic Levelling System (HLS) of the SLS was installed and commissioned in year 2000. It is a measurement system for monitoring the vertical positions of the SLS storage ring girders. It is integrated in the concept of dynamic alignment. The HLS was modified and re-calibrated in 2002. Since January 2003 the system has collected approximately 2 million measurements. The analysis of the data shows that displacement of the SLS storage ring foundation and the girder support was in the range of 0.15 mm in year 2003. The long term HLS stability was significantly improved. The short term precision of the HLS is in the micrometer range. The experience gained on the HLS is presented.
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WEPKF029 | The Vacuum System of the Australian Synchrotron | vacuum, dipole, synchrotron, synchrotron-radiation | 1663 | ||||||
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A 3 GeV Synchrotron Radiation Source is being built in Melbourne, Australia. The storage ring has a circumference of 216 m and has a 14 fold DBA structure. The vacuum chambers of the storage ring will be made from stainless steel. They consist of a beam chamber (width 70, height 32mm ) connected to an ante chamber, where lumped absorbers and lumped ion pumps are installed. No distributed absorber and pumps are foreseen. The nominal pumping speed of the complete ring is 31 000 l/s. The vacuum chamber of an achromat will be baked ex situ and installed under vacuum. The design of the chamber, the pump configuration and the expected vacuum behaviour will be presented.
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WEPKF030 | The Storage Ring Magnets of the Australian Synchrotron | quadrupole, sextupole, dipole, focusing | 1666 | ||||||
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A 3 GeV Synchrotron Radiation Source is being built up in Melbourne, Australia. The storage ring has a circumference of 216 m and has a 14 fold DBA structure. For the storage ring the following magnets are required: 28 gradient dipoles, with B = 1.3 T, B = 3.35 T/m, 56 quadrupoles with a gradient of B = 18 T/m, 28 quadrupoles with a gradient of 9 T/m, 56 sextupoles with d2B/dr2 = 320 T/m2 and 42 with 150 T/m2. The design of pole faces was done by scaling the SPEAR III pole face to the required gap and bore of the ASP storage ring magnets. The sextupoles will be equipped with coils for horizontal and vertical correction and for a skew quadrupole. The design of the magnets and the calculated magnetic properties will be presented.
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WEPKF032 | A General Method for 2d Magnet Pole Design | synchrotron, quadrupole, dipole, cyclotron | 1672 | ||||||
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Accurate conventional combined magnets working in saturation are currently required to fulfil the increasing demands on low emittance accelerators with long straight sections required by the newest Synchrotron Light Sources. This fact yields stringent requirements on pole profile design, manufacture and characterization. The aim of this poster is to present a general method for designing two-dimensional pole profiles. To this end, we have set up a procedure with which to select an optimum pole profile in 2D without the constraint of relying on a set of initial assumptions, not only a particular set of initial parameters but even a particular pole profile model. Moreover, we have developed a group of codes that can be compiled and run on MS-DOS or UNIX which use POISSON or OPERA-2d codes. This procedure also includes the evaluation of the sensitivity of the final pole profile to geometrical and current intensity errors for tolerance estimation, a big requirement in this context. In order to test the feasibility of this method, we have applied it to the case of the 1.2 T combined magnet of the new synchrotron to be built nearby Barcelona.
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WEPKF042 | Installation and Operation of New Klystron Power Supply with Fast Solid-State Switch for Klystron Protection at the Photon Factory Storage Ring | power-supply, klystron, factory, photon | 1699 | ||||||
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In the 2.5-GeV Photon Factory storage ring at KEK, there are four klystron power supplies which typically operate at an output voltage of -40 kV with 8 A. We replaced one of these power supplies during 2003 and the new power supply is in operation. This power supply is equipped with a solid-state high-voltage (HV) switch for klystron protection. This HV switch is made up of eighty insulated gate bipolar transistors (IGBT), and it can turn the high-voltage off within a few tens of microseconds in cases of any discharges in the klystrons. We report the performance of this new power supply.
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WEPKF043 | Measurement of the Vertical Quadrupolar Tune Shift in the Photon Factory Storage Ring | betatron, single-bunch, factory, photon | 1702 | ||||||
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We measured the frequencies of vertical quadrupole oscillations in the 2.5-GeV Photon Factory storage ring at KEK. The measured vertical quadrupole tunes showed remarkable dependence of about -7.5E-5/mA on the bunch current. This contrasts with our previous result of about +4.8E-5/mA (presented in PAC2003) for the horizontal quadrupole tune shift. These results will suggest that the transverse wake forces in a quadrupolar mode contribute significantly to the transverse motions of particles in the Photon Factory storage ring.
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WEPKF060 | Bending Magnets for the SAGA Storage Ring: Manufacturing and Magnetic Measurements | dipole, multipole, focusing, electron | 1738 | ||||||
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The paper describes the design, the manufacture and the magnetic measurement of the dipole bending magnets (BM) for SR Source storage ring (prefecture SAGA, Japan) carried out in BINP, Novosibirsk, Russia. The requirement was to create the laminated C-shape BMs with the 3.2 m radius and parallel edges. The magnetic field homogeneity must be not worth than ±2? 10-4 inside the working area: H = 30+40mm and V = ±20mm at 0.26T (250 MeV), and H = ± 28mm and V = ±20mm at 1.46 T (1.4GeV). The BMs were designed on the basis of the 2-D 3-D modeling taking into account the laminated core. The BMs yokes were produced with the help of the technology of the high temperature gluing. The computer simulations are in a good agreement with the magnetic measurements. The main parameters of the magnetic fields satisfy to the requirements and are presented. The features of the design, manufacturing and precise magnetic measurements of SAGA BMs are discussed.
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WEPKF068 | Developments in Magnet Power Converters at the SRS | power-supply, booster, septum, kicker | 1759 | ||||||
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A project to upgrade the magnet power converters of the SRS has commenced to ensure its efficient operation for its remaining operational lifetime. A recent risk analysis of the facilities equipment identified that the main areas for concern were the Storage Ring magnet power converters, kicker and septum pulse power supplies and the Booster Dipole "White Circuit" and associated power converters. This report detail the development and replacement programs currently active at Daresbury Laboratory, including future work identified to support and improve SRS utilisation.
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WEPKF071 | A New Current Regulator for the APS Storage Ring Correction Magnet Bipolar Switching Mode Power Converters | power-supply, controls, photon | 1768 | ||||||
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The correction magnets in the Advanced Photon Source's storage ring are powered by PWM-controlled bipolar switching-mode converters. These converters are designed to operate at up to ± 150 A. The original current regulator used a polarity detection circuit, with a hysteresis, to determine which IGBT was needed to regulate the current with a given polarity. Only the required IGBT was switched while others were held on or off continuously. The overall IGBT switching losses were minimized by the design. The shortcoming of the design is that the converter's output is unstable near zero current because of the hysteresis. To improve the stability, a new current regulator, using a different PWM method, has been designed to eliminate the requirement of the polarity detection. With the new design, converters can operate smoothly in the full range of ±150 A. The new design also meets tighter specs in terms of the ripple current and dynamic response. This paper describes the design of the new regulator and the test results.
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WEPLT001 | Nonlinear Beam Dynamics Study with MATLAB | simulation, lattice, quadrupole, synchrotron | 1813 | ||||||
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In this paper, we present description of MATLAB based computer code, which allows tracking of single particles by numerical integration of Hamilton's equations. For storage rings the damping time is of the order of few ms (102 '104 turns) and therefore the short-term stability time is determinant. For this reason symplecticity condition of the tracking method for the electron machines is not as important as in hadron machines. Applying recently introduced modern tools for post process analyzing, such as interpolated FFT, early indicators for long term stability, the determination of the onset of chaotic behavior using the maximal Lyapunov exponent, and etc, one can carry out simulations to evaluate the dynamic aperture, amplitude dependent tunes, phase space distortions, nonlinear resonances etc. The proposed code is applied for beam nonlinear dynamics study in CANDLE storage ring.
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WEPLT002 | Shielding Design Study for CANDLE Facility | shielding, beam-losses, radiation, electron | 1816 | ||||||
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The radiation shielding design study for the third generation synchrotron light source CANDLE is carried out. The electron beam loss estimates have done for all the stages from linac to storage ring. A well-known macroscopic model describing the dose rate for point losses has been used to calculate the shielding design requirements of the facility.
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WEPLT050 | Frequency Map Measurements at BESSY | sextupole, resonance, lattice, quadrupole | 1951 | ||||||
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With two dedicated diagnostic kicker magnets and a turn-by-turn, bunch-by-bunch beam position monitor frequency maps were measured under various operating conditions of the BESSY storage ring. Depending on the number and type of insertion devices in operation additional resonances show up. Details of the experimental setup as well as the data analysis are presented. The results will be compared with theoretical calculations which are based on the linear model of the storage ring lattice extracted from measured response matrices. Non-linear elements are added to the model in order to describe the effect of the strong sextupole magnets, the horizontal corrector magnets installed in these magnets, and of some of the insertion devices.
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WEPLT051 | Sub-Picosecond Electron Bunches in the BESSY Storage Ring | electron, synchrotron, radiation, optics | 1954 | ||||||
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BESSY is a low emittance, 1.7 Gev electron storage ring. A dedicated, low alpha optics is applied to produce short electron bunches for coherent synchrotron radiation (CSR) in the THz range[*]. By a further detuning of the optics, stable pulses as short as 0.7 ps rms length were produced. The sub-ps pulse shape is analysed by an auto-correlation method of the emitted CSR. The CSR-bursting instability is measured and compared with theory to estimate the current for stable, sub-ps pulses. Present limits of the low alpha optics are discussed.
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* M. Abo-Bakr et al., Phys. Rev. Lett. 88, 254801 (2002). |
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WEPLT055 | Observation of Ultracold Heavy Ion Beams with Micrometer Size by Scraping | ion, electron, emittance, heavy-ion | 1966 | ||||||
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The existence of an ordered beam state for low intensity, electron cooled heavy ion beams has been evidenced by a sudden reduction of the momentum spread. The detection of a similar effect in the transverse degree of freedom by non-destructive diagnostics is ruled out by the limited resolution of beam profile detectors. A method to probe the horizontal beam size of an electron cooled beam in a dispersive section has been developed. It is based on beam scraping and allows a resolution on the order of micrometers. This good transverse resolution for the cooled ion beam is achieved by precise changes of the ion energy which is varied by changes of the electron beam energy. The lower resolution limit due to power supply ripple is estimated to be below 1 micrometer. This method evidenced that the reduction of the momentum spread by one order of magnitude coincides with a reduction of the transverse beam emittance by 2-3 orders of magnitude, at least. A horizontal beam radius of a few micrometer could be demonstrated for electron cooled heavy ion beams with less than 1000 particles. This gives new evidence for the formation of an ordered beam arranged as a linear string of ions.
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WEPLT056 | An Electron Cooling System for the Proposed HESR Antiproton Storage Ring | electron, antiproton, target, acceleration | 1969 | ||||||
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The HESR storage ring in the proposed new international accelerator facility will provide high quality antiproton beams for experiments with an internal target. In order to achieve the design luminosity for collisions with a hydrogen target powerful beam cooling is required. For dedicated experiments ultimate resolution is demanded. Therefore it is foreseen to provide cooled antiproton beams in the energy range 0.8-14 GeV with an energy spread of 100 keV or better. According to computer simulations the required cooling rates can be achieved by electron cooling with an electron current of 1 A. The conceptual design of an electron beam device which is based on electrostatic acceleration of the electrons and their transport in longitudinal magnetic fields into a cooling section with a strong magnetic field of up to 0.5 T will be presented. This design will allow cooling in the magnetized regime in order to reach the required high cooling rates. Some novel features for the generation and regulation of the accelerating voltage and for the beam transport are proposed.
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WEPLT063 | Investigation of Cavity Induced Longitudinal Coupled Bunch Mode Instability Behaviour and Mechanisms | damping, synchrotron, simulation, radiation | 1990 | ||||||
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The narrowband impedances of RF-resonators in a circular accelerator can drive coupled bunch mode - CBI - instabilities which might spoil the overall beam quality. Often, as in synchrotron radiation light sources e.g. the instability does not lead to beam loss but to a severe degradation of the source brilliance. Investigations of longitudinal CBIs have been performed at the DELTA storage ring with a single DORIS-type cavity for future comparision with the behaviour of a HOM-damped cavity to be tested at DELTA. This resonator is presently developed and built within an EU-collaboration. The beam was deliberately driven into instability using the beam current as well as the cavity temperature as individual parameters. The instability characterisations at low (542 MeV) and high (1,5 GeV) energy exhibit a complex behaviour. The strength of the instability measured by the bunch excursions in the case of longitudinal CBIs, but also the spreading of the instability across neighbouring modes depends on parameters such as beam energy, resonant impedance but also on counteracting mechanisms like synchrotron radiation and Landau damping. The paper will cover the experimental results together with estimations of the influence and mechanism of Landau damping.
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WEPLT068 | Momentum Compaction Factor and Nonlinear Dispersion at the ANKA Storage Ring | optics, synchrotron, electron, synchrotron-radiation | 2005 | ||||||
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The ANKA electron storage ring operates in the energy range from 0.5 to 2.5 GeV. In order to improve machine performance a precise modelling of linear and nonlinear optics is mandatory. Apart from higher order chromaticity also momentum compaction factor and dispersion have to be controlled. In this framework, the higher order momentum compaction factor has been determined exploiting the extraordinary precision of the resonant spin depolarisation method. Furthermore the nonlinear horizontal dispersion was measured as a function of the momentum deviation for different chromaticities. This paper discusses the experimental results and compares the findings to different simulations.
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WEPLT069 | Investigation of Scraper Induced Wake Fields at ANKA | impedance, closed-orbit, synchrotron, single-bunch | 2008 | ||||||
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The ANKA synchrotron light source operates in the energy range from 0.5 to 2.5 GeV. Typical requirements for light sources include small beam sizes, large lifetimes and high currents to provide the highest possible photon flux. The understanding of impedance and instability related issues is very important in order to improve the machine performance, in particular when small aperture insertion devices are installed that require protection by a scraper. In the framework of an impedance survey the transverse and longitudinal wake fields induced by a vertical scraper have been measured and analysed. This paper reports the beam observations and compares them with the expectation.
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WEPLT070 | Studies of Current Dependent Effects at ANKA | impedance, synchrotron, betatron, closed-orbit | 2011 | ||||||
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The ANKA electron storage ring is operated at energies between 0.5 and 2.5 GeV. A major requirement for a synchrotron light source, such as ANKA, is to achieve a high beam current. A multitude of mostly impedance related effects depend on either bunch or total beam current. This paper gives an overview over the various beam studies performed at ANKA in this context, specifically the observation of current dependent detuning, the dermination of the bunch length change with current from a measurement of the ratio between coherent and incoherent synchrotron tune and an assessment of the effective longitudinal loss factor from the current dependent horizontal closed orbit distortion.
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WEPLT083 | Coherent and Incoherent Tune Shifts Deduced from Impedance Modelling in the ESRF-Ring | impedance, vacuum, single-bunch, coupling | 2047 | ||||||
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In single bunch the detuning of the transverse modes m=0,1 and -1 are calculated on the base of an impedance model contructed from element-wise wakefield calculation and the resistive wall impedance of the ESRF-ring. As the vacuum chambers of the ESRF storage ring have notably flat cross sections incoherent wake fields have an impact on the tune shifts as well as coherent wake fields. Compared to tune shift measurements in single bunch the calculated transverse mode detuning can explain half of the tune shift in the vertical plane and almost completely the tune shift in horizontal plane.
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WEPLT084 | Experimental Frequency Maps for the ESRF Storage Ring | kicker, resonance, dynamic-aperture, optics | 2050 | ||||||
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Experimental frequency maps have already revealed many unknown characteristics of the ESRF storage ring non-linear dynamics. In the past year, several efforts were undertaken in order to establish this technique as an operational on-line tool. The acquisition time was significantly reduced by collecting data from a dedicated fast BPM system. The problem of beam decoherence was limited by establishing a method for accurate tune determination in a small number of turns, using the information from all the BPMs around the ring. The possibility to explore the off-momentum dynamics by exciting the beam, with synchronous transverse and longitudinal kicks was also investigated. Finally, measurements of resonance driving term amplitudes and phase advances were used to identify the efficiency of resonance corrections.
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WEPLT106 | Growth and Suppression Time of an Ion-related Vertical Instability | octupole, factory, photon, betatron | 2098 | ||||||
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In the KEK Photon Factory electron storage ring, a vertical instability has been observed in a multi-bunch operation mode. The instability can be suppressed by octupole magnetic field in routine operation. Since the instability depends on a vacuum condition in the ring, it seems that it is an ion-related phenomenon. In order to study this instability, we measured the growth and the suppression time of it with the pulse octupole magnet system, which can produce the octupole field with rise and fall time of around 1.2msec. We obtained the result that the instability was grown slowly compared with to suppress it, and the growth time depended on the fill pattern of the bunch train and the beam current per bunch.
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WEPLT117 | Design of a Third Harmonic Superconducting RF System at PLS | emittance, vacuum, synchrotron, radiation | 2125 | ||||||
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A superconducting third harmonic rf system has been designed in the PLS to raise beam lifetime. Expected beam lifetimes verse beam emittance and operational beam current are presented. A multibunch multiparticle tracking simulation is performed to investigate energy spread, bunch-lengthening and beam instabilities due to the rf cavities. The parameters of the designed rf cavity, designed cryogenic system and estimation of heat load are also presented.
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WEPLT120 | Control Environment for the Superconducting Insertion Devices at NSRRC | power-supply, insertion, insertion-device, wiggler | 2134 | ||||||
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To enhance hard X-ray capability in the 1.5 GeV storage ring of NSRRC to serve the rapidly growing X-ray user community in Taiwan, the storage ring was installed two superconducting insertion devices. Three more superconducting insertion devices are in planning. A 6 Tesla superconducting wavelength shifter was installed in mid-2002. A 3.2 Tesla superconducting multi-pole wiggler was installed in December of 2003. Control system and operation environment have been set up to support the operation of the superconducting insertion devices. The implementation and operation experiences will be summarized in this report.
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WEPLT121 | Computer Simulation of Equilibrium Electron Beam Distribution in the Proximity of 4th Order Single Nonlinear Resonance | resonance, simulation, electron, radiation | 2137 | ||||||
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The beam distribution of particles in an electron storage ring is distorted in the presence of nonlinear resonances. A computer simulation is used to study the equilibrium distribution of an electron beam in the presence of 4th order single nonlinear resonance. The results are compared with that obtained using an analytical approach by solving the Fokker-Planck equation to first order in the resonance strength. The effect of resonance on the quantum lifetime of electron beam is also compared and investigated.
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WEPLT122 | Investigation of Microwave Instability on Electron Storage Ring TLS | impedance, simulation, damping, single-bunch | 2140 | ||||||
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With the planned installation of a superconducting rf system, the new operation mode of TLS, the electron storage ring at NSRRC, is expected to double the beam intensity. Several accelerator physics topics need to be examined. One of these topics concerns the beam instability of single-bunch longitudinal microwave instability. We consider different approaches to measure the effective broad band impedance. We compare these measurement results with each other and to the old data [*]. The new measurements of effective broad band impedance are higher than the old measurement since between these two sets of measurements several narrow gap insertion devices were installed into the storage ring. We calculate the threshold current of microwave instability with a mode-mixing analysis code written by Dr. K. Oide of KEK [**]. We also develop a multi-particle tracking code to simulate the instability. The results of simulation and measurement are compared and discussed. We conclude that the doubling of beam current will not onset the microwave instability even without a Landau cavity to lengthen the bunch.
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* M.H. Wang, et al.,"Longitudinal Beam Instability Observation with streak Camera at SRRC", proceeding of 1996 European Particle Accelerator Conference, pp. 1120** K. Oide, "Longitudinal Single-Bunch Instability in Electron Storage Rings", KEK Preprint 90-10 |
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WEPLT144 | New Characteristics of a Single-bunch Instability Observed in the APS Storage Ring | betatron, single-bunch, synchrotron, lattice | 2173 | ||||||
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In the Advanced Photon Source storage ring, a transverse single-bunch instability has long been observed that appears unique to this ring. Many of its features have been previously reported. New results have recently been obtained using beam centroid history measurements and analysis. These preliminary results provide more detailed information regarding the characteristics of this instability and could provide insight into the physics mechanism.
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WEPLT147 | Lattice Studies for CIRCE (Coherent InfraRed CEnter) at the ALS | lattice, dynamic-aperture, emittance, quadrupole | 2182 | ||||||
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CIRCE (Coherent InfraRed Center) at the Advanced Light Source is a proposal for a new electron storage ring optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range. One of the main requirement for this special mode of operation is the capability of the ring of operating at very small momentum compaction values. In this regime, the longitudinal dynamics becomes strongly nonlinear and an accurate control of the higher order energy dependent terms of the momentum compaction is necessary. The lattice for CIRCE allows controlling these terms up to the third order. The paper describes the lattice and presents the calculated performances in terms of momentum acceptance, dynamic aperture, lifetime and momentum compaction tune capabilities.
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WEPLT159 | Linear Vlasov Analysis for Stability of a Bunched Beam | synchrotron, damping, synchrotron-radiation, coupling | 2215 | ||||||
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We study the linearized Vlasov equation for a bunched beam subject to an arbitrary wake function. Following Oide and Yokoya, the equation is reduced to an integral equation expressed in angle-action coordinates of the distorted potential well. Numerical solution of the equation as a formal eigenvalue problem leads to difficulties, because of singular eigenmodes from the incoherent spectrum. We rephrase the equation so that it becomes non-singular in the sense of operator theory, and has only regular solutions for coherent modes. We report on a code that finds thresholds of instability by detecting zeros of the determinant of the system as they enter the upper-half frequency plane, upon increase of current. Results are compared with a time-domain integration of the nonlinear Vlasov equation, and with experiment, for a realistic wake function for the SLC damping rings.
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WEPLT169 | Benchmark and Threshold Analysis of Longitudinal Microwave Instability in the PSR | injection, space-charge, impedance, proton | 2224 | ||||||
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A set of inductive inserts used to provide passive longitudinal space charge compensation in the Los Alamos Proton Storage Ring cause a strong microwave instability in the beam when the inductors are at room temperature. We use the ORBIT code to perform benchmarks of the microwave instability dynamics, including the mode spectrum and the instability growth time. Additionally, we analyze the experimental instability intensity threshold and compare it with the simulated threshold. For all parameters benchmarked, results of simulations are in good agreement with the experimental data.
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THXCH01 | Achieving Sub-micron Stability in Light Sources | feedback, quadrupole, photon, resonance | 211 | ||||||
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One of the major goals for present and future light sources is to achieve sub-micron orbit stability of the electron beam at the photon beam source points over a large frequency range. This puts tight constraints on the design of the various accelerator components like girders, magnets, power supplies and diagnostic hardware. Fast orbit feedbacks systems based on high performance RF- and X-BPMs become essential to suppress residual orbit distortions. Furthermore the "top-up" operation mode which guaranties a constant electron beam current and thus a constant heat load in 3rd generation light sources is one of the key ingredients to reach sub-micron stability.
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Video of talk
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THOACH01 | SPEAR3 Commissioning | dynamic-aperture, closed-orbit, feedback, resonance | 216 | ||||||
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Starting in April, 2003, the SPEAR2 storage ring was removed and replaced with a new 500 mA, 3 GeV light source, SPEAR3. The SPEAR2 storage ring had been in use for high energy physics, then synchrotron radiation since 1972. Commissioning of SPEAR3 started on December 8, 2003 and synchrotron radiation will be delivered to the first users on March 8, 2004. SPEAR3 commissioning will be reviewed, including discussion of diagnostics, orbit control, optics correction and high current studies.
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THOACH02 | Commissioning of the 500 MeV Injector for MAX-lab | linac, gun, electron, injection | 219 | ||||||
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A 500 MeV new injector system for the storage rings MAX I, II and III have been installed during the winter 2003-4 at MAX-lab. The system consists of two linacs at 125 MeV each, using SLED, and a recirculating system such that the electrons pass the linacs twice, thus reaching a final energy of 500 MeV. The system is injected by a thermionic RF-gun. The commissioning of the complete system will be performed in the spring 2004.
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THOACH03 | Top-up Operation at SPring-8 - Towards Maximizing the Potential of a 3rd Generation Light Source | injection, target, beam-losses, single-bunch | 222 | ||||||
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Top-up operation maximizes research activities in a light source facility by an infinite beam lifetime and photon beam stability. We have been improving the SPring-8 accelerators to achieve the ideal top-up operation. For the perturbation-free injection, we adjusted the magnetic field shape of four bump magnets to close the bump orbit, and introduced a scheme to suppress the stored beam oscillation induced by the nonlinearlity of sextupole magnets. These reduced the horizontal oscillation down to a third of the stored beam size. For the loss-free injection, beam collimators were installed upstream of the injection line. This realized the injection efficiency of ~100% under the restricted gap condition of in-vacuum insertion devices (ID). Since autumn 2003, we have been injecting the beams keeping the photon beam shutters opened and ID gaps closed. We developed a bunch-by-bunch feedback system to reduce the beam loss further with all the ID gaps fully closed by lowering the operating chromaticity. The operation with constant stored current is scheduled in June 2004. We present the overview and progress of the SPring-8 top-up operation focusing on our developments and results.
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THZCH02 | Electron Cooling: Remembering and Reflecting | electron, ion, proton, antiproton | 244 | ||||||
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The report contains a brief review of developments in electron cooling methods. The influence of electron cooling concepts on progress in particle beam physics is considered, particularly: development of alternative and complementary cooling methods - stochastic, laser, muon cooling; physics of cooled and intense particle beams; ordering effects in cooled ion beams and the idea of crystalline beams; intrabeam scattering in cooled beams, etc. Creation of new accelerator technology, based on electron cooling and its application to different fields of experimental physics, particle, nuclear and atomic physics, is described. Modern trends and new concepts of electron cooling applications are discussed.
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THOBLH03 | BESSY II Operated as a Primary Source Standard | electron, photon, radiation, synchrotron | 273 | ||||||
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The Physikalisch-Technische Bundesanstalt (PTB) is the German National Metrology Institute and responsible for the realization and dissemination of the legal units in Germany. For the realization of the radiometric units in the VUV and X-ray spectral range PTB has been using calculable synchrotron radiation of bending magnets from the BESSY I and BESSY II electron storage rings for more than 20 years. The spectral photon flux of synchrotron radiation can be precisely calculated by Schwinger's theory. Therefore, all the storage ring parameters entering the Schwinger equation have to be measured with low uncertainty which requires a stable and reproducible operation of the storage ring. At BESSY II, PTB has installed all equipment necessary to measure the electron energy, the electron beam current, the effective vertical source size and the magnet induction at the radiation source point as well as all geometrical quantities with low uncertainty. The measurement accuracy for these quantities enables PTB to calculate the spectral photon flux from the visible up to the soft X-ray range with relative uncertainties below 0.4 %. We report on the measurement of the storage ring parameters with low uncertainty.
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THPKF004 | The Australian Synchrotron Project - Update | synchrotron, injection, site, insertion | 2260 | ||||||
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The Australian Synchrotron - a 3rd generation synchrotron light facility based on a 3-GeV electron storage ring - is under construction at a site adjacent to Monash University in the Metropolitan District of Melbourne. Site preparation started in September 2003 and project completion is scheduled for March 2007. In this paper we present an overview of the facility and discuss progress to date in meeting this very agressive schedule.
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THPKF005 | The Australian Synchrotron Project Storage Ring and Injection System Overview | synchrotron, lattice, injection, dipole | 2263 | ||||||
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This paper describes the Australian Synchrotron storage ring. The storage ring is a 3 GeV machine with 14 cells and a circumference of 216 m. The unit cell is based on a Double Bend Achromat (DBA) structure. The design of the magnet lattice and the results of simulations pertaining to the storage ring performance are presented.
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THPKF006 | Lifetime Studies in the LNLS Electron Storage Ring | scattering, synchrotron, coupling, single-bunch | 2266 | ||||||
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In this paper we present a set of measurements performed at the 1.37 GeV electron storage ring of the Brazilian Synchrotron Light Source. We measured the beam lifetime as a function of: current per bunch, gap voltage and position of horizontal and vertical scrapers. Those measurements helped us to determine the contribution of various particle loss mechanisms (Touschek, elastic and inelastic scattering and quantum fluctuations) to the lifetime of the beam. Comparison with theory is also presented as well as an interpretation of each effect.
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THPKF007 | Canadian Light Source Status and Commissioning Results | quadrupole, injection, dipole, sextupole | 2269 | ||||||
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The storage ring for the Canadian Light Source (CLS) was completed in August 2003. By January 2004, after about shifts of commissioning beam currents of up to 25 mA with 0.7 hr lifetimes were achieved. Injection times for 25 mA are about 4 minutes. Commissioning activities include global orbit correction, measurement of machine parameters and beam-based diagnostices. Features of the CLS are a compact lattice (170 m) for a 2.9 GeV storage ring, high performance magnets and a superconducting RF cavity. By July, when beamlines become operational, currents up to 100 mA with 4 hour lifetimes are expected.
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THPKF008 | Injection System for the Canadian Light Source | injection, booster, linac, septum | 2272 | ||||||
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The full energy injection system for the Canadian Light Source is made up of a 250 MeV linac, a low energy transfer line, a 2.9 GeV booster synchrotron and a high energy transfer line. The system has routinely provided up to 25 mA peak current in a 132 ns pulse train to the CLS storage ring injection point since September 2003. By January, 2004, injection efficiencies up to 10% have been acheived and stored currents up to 25 mA were accumulated in less than 4 minutes. The injection timing system allows a variety of fill patterns. By July, 2004, injection rates of up to 2 mA per second should be possible providing a fill time of under one minute for a 100 mA stored beam.
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THPKF009 | Orbit Control for the Canadian Light Source | feedback, power-supply, booster, injection | 2275 | ||||||
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The orbit control system for the Canadian Light Source storage ring is design to provide both static global orbit correction and active correction up to 100 Hz. The system is made up of 48 button monitors (X and Y), 24 fast correcter magnets (X and Y), and 24 slow correction coils in sextupole magnets (X and Y). To date the system has been use to apply static corrections the to CLS storage ring. While some works remains on the horizontal correction, the vertical orbit has been corrected to an RMS value of less tha 0.75 mm. Future corrections may be augmented by some beam-based magnet re-alignment. The orbit correction system is run on a MATLAB(R) operating system. Singular value decompostion (svd) was used extensively to reduce initial gross mis-alignments.
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THPKF014 | Status of the BESSY II Femtosecond X-ray Source | laser, electron, radiation, wiggler | 2287 | ||||||
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At the BESSY II storage ring, work is in progress to produce X-ray pulses with 50 fs (fwhm) duration and tunable energy and polarization by "femtoslicing" [*].This work includes extensive alterations to the storage ring (one new and one modified undulator, both in the same straight section, three additional dipole magnets, a new IR beamline, and nine meters of new vacuum vessels) and to two beamlines (relocation and new optical designs), as well as the installation of a femtosecond Ti:sapphire laser system. Commissioning is planned for May 2004. This paper reviews the principles and technical implementation of the new femtosecond X-ray source, and reports the status of the project.
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* A. Zholentz, M. Zoloterev, Phys.Rev.Lett. 76 (1996), 912 |
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THPKF016 | The Metrology Light Source of the Physikalisch-Technische Bundesanstalt in Berlin-Adlershof | electron, radiation, photon, synchrotron | 2293 | ||||||
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PTB, the German National Metrology Institute, has gained approval for the construction of a low-energy electron storage ring in the close vicinity of BESSY II, where PTB operates a laboratory for X-ray radiometry. The new storage ring, named 'Metrology Light Source MLS' will be dedicated to metrology and technology development in the UV and EUV spectral range and so will fill the gap that is present since the shut down of BESSY I. The MLS is designed in close cooperation with BESSY and is located adjacent to the BESSY II facility. Construction will start 2004 and user operation is scheduled to begin in 2008. The MLS has a circumference of 48 m, injection will be from a 100 MeV microtron. The electrons energy is ramped to an eligible value in the range from 200 MeV to 600 MeV. The MLS will be equipped with all the instrumentation necessary to measure the storage ring parameters needed for the calculation of the spectral photon flux according to the Schwinger theory with low uncertainty, enabling PTB to operate the MLS as a primary source standard. Moreover, provision is taken to operated the MLS in a low alpha mode for the production of coherent synchrotron radiation in the far IR and THz region.
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THPKF018 | Study for a Frequent Injection Mode at Delta with Beam Shutters Open | injection, radiation, feedback, synchrotron | 2299 | ||||||
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The Dortmunder Electron Accelerator (DELTA) is a 1.5 GeV synchrotron light source. DELTA is now operated for 3000 h per year including 2000 h beam time for synchrotron radiation use. The maximum beam current is limited by rf power. To increase the average beam current a frequent injection scheme with beam shutters open is discussed for Delta. The peak current is not enlarged but the number of injections is increased to establish a quasi constant beam current. The quasi constant beam current has in addition the advantage of a constant synchrotron radiation heat-load on vacuum chambers and experiments. First tests at Delta have shown the gain in stability of the closed orbit during frequent injection. This article shows the possibility to install a frequent injection mode with beam shutters open during injection at DELTA. The results of measurements and simulations are presented.
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THPKF022 | Energy Calibration of the ANKA Storage Ring | synchrotron, resonance, energy-calibration, synchrotron-radiation | 2311 | ||||||
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The ANKA electron storage ring operates in the energy range from 0.5 to 2.5 GeV. An energy calibration using the method of resonant spin depolarisation yields the exact beam energy of ANKA. In addition this method allows to determine other parameters such as nonlinear momentum compaction factor and incoherent synchrotron tune with extraordinary precision. This paper discusses experimental set-up and energy measurements. The reproducibility of the ANKA beam energy is addressed as well as energy drifts caused by thermal expansion of the floor.
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THPKF023 | Studies using Beam Loss Monitors at ANKA | beam-losses, vacuum, electron, injection | 2314 | ||||||
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ANKA is a synchrotron light source that operates in the energy range from 0.5 to 2.5 GeV. In order to investigate the electron beam losses, two kind of beam loss monitors have been installed: 24 Pin Diode from Bergoz distributed around the storage ring, and one Pb-glass calorimeter located in a high dispersion region. The Pin Diodes are used to obtain information about the distribution of the losses while the Pb-glass detector provides higher sensitivity. The Pin Diodes allow to locate and distinguish the regions of higher losses due to Touschek and Elastic scattering. Furthermore, regions of higher losses at injection have been identified. The Pb-glass detector has been used to determine the beam energy with the resonant spin depolarisation technique. A strong spin orbit resonance has been observed with both detectors.
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THPKF028 | Upgrade of the Cryomodule Prototype before its Implementation in SOLEIL | damping, dipole, impedance, synchrotron | 2329 | ||||||
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In the Storage Ring (SR) of the Synchrotron SOLEIL light source, two cryomodules will provide the maximum power of 600 kW required at the nominal energy of 2.75 GeV with the full beam current of 500 mA. A cryomodule prototype, housing two 352 MHz superconducting single-cell cavities with strong damping of the Higher Order Modes has been built and successfully tested in the ESRF storage ring. Even though the achieved performance (3 MV and 380 kW) does meet the SOLEIL requirement for the 1st year of operation, the cryomodule prototype will be upgraded before its installation in the SR early 2005. Modifications will be made on the internal cryogenic system, and also on the power and dipolar HOM couplers. That requires a complete disassembling and reassembling of the cryomodule, which is being carried out at CERN in the framework of collaboration between SOLEIL, CEA and CERN. Additional 3D RF calculations have been performed on the full SOLEIL RF structure in order to get a more detailed description of the dipolar modes damping and of the dipolar HOM couplers tuning. A second cryomodule, similar to the modified prototype, will be built and installed in the SR about one year later.
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THPKF030 | Progress Report on the construction of SOLEIL | dipole, quadrupole, booster, sextupole | 2335 | ||||||
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The construction of SOLEIL, the French new SR facility, was launched in Jan 2002. The construction of the building has started in Aug 2003 and will enable a progressive beneficial occupancy from summer 2004 onwards. It is foreseen to achieve the commissioning of the 100 MeV Linac by the end of 2004, of the 3 Hz Booster in spring 2005 and of the 2.75 GeV Storage Ring by the end of 2005. All the major components have been ordered and some have already been delivered : the Booster and SR dipole magnets, the Linac sections and the Booster RF cavity. Some innovative development have been initiated specifically for SOLEIL: A 352 MHz SC RF cavity, solid state RF amplifiers for the Booster (40 kW) and the Ring (2 x 190 kW), BPM digital electronics, Al NEG coated vacuum vessels for all straight parts of the ring, or electromagnetic undulators to provide high brilliance polarized light in the VUV range. In order to provide the best performances, significant attention was paid at each design stage (optics, magnets, BPM, vacuum and RF systems,..), involving a large effort of simulation, using 6D tracking codes, or evaluating in detail the contribution of each component to the machine impedance.
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on behalf of the SOLEIL project team |
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THPKF035 | Design of the Super-SOR Light Source | synchrotron, injection, linac, optics | 2350 | ||||||
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The Super-SOR light source is a Japanese VUV and soft X-ray third-generation synchrotron radiation source, which is to be operated for nation-wide and world-wide users. The University of Tokyo has proposed to construct the facility in Kashiwa new campus and we have designed the light source intensively for more than two years. The light source consists of an electron storage ring, booster synchrotron and pre-injector linac. The 1.8-GeV storage ring has a circumference of about 280 m and 14 DBA cells with two 17-m and twelve 6.2-m long straight sections, which are used for twelve insertion devices and RF and injection systems. The booster synchrotron is compact, one third of the ring in circumference, and can achieve a low emittance of about 50 nmrad at 1.8 GeV. The 200-MeV linac is made up of S-band accelerating structures powered by two 50-MW klystrons and a SLED cavity and capable of changing the beam current widely in both single- and multi-bunch operation modes. These accelerators are designed so as to fully meet requirements for top-up injection. We describe the design of the Super-SOR accelerators here.
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on behalf of the Super-SOR accelerator design group |
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THPKF038 | Radiation Damage of Magnet Coils due to Synchrotron Radiation | radiation, acceleration, synchrotron, synchrotron-radiation | 2359 | ||||||
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Radiation damage of the equipment in the SPring-8 storage ring tunnel has become a serious problem. In the storage ring, the unnecessary radiation from bending magnets is shielded by absorbers. The equipment around the absorbers was damaged by the scattered radiation from the absorbers. Last year, cooling water leaked from the rubber hose of magnets. It was due to the deterioration of rubber hose caused by synchrotron radiation. We measured the radiation distribution around the storage ring and found that the most high intensity spot was on the magnet coil near the absorbers. If the coils are damaged and the magnets do not work correctly, we need to shut down the storage ring to exchange the magnet coils. To avoid such a situation, we needed to clarify the relation between the radiation damage of the coils and the dose of radiation. We did an acceleration test of the radiation damage of magnet coils. The magnet coils were exposed to the radiation from the bending magnet directly. We observed the degree of damage with changing the doses of radiation. In this paper, we describe about these acceleration tests and test results.
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THPKF041 | SSRF: A 3.5GeV Synchrotron Light Source for China | injection, booster, synchrotron, undulator | 2368 | ||||||
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The Shanghai Synchrotron Radiation Facility (SSRF) is an intermediate energy light source that will be built at Zhang-Jiang Hi-Tech Park in Shanghai. The SSRF consists of a 432 m circumference storage ring with an operating energy of 3.5GeV and a minimum emittace of 2.95 nm-rad, a full energy bosster, a 100MeV electron Linac and dozens of beamlines and experimental stations. The design of the SSRF accelerator complex evolves timely along the technological progress such as top-up injection, mini-gap undulator, superconducting RF system and etc. This paper reports the design progress and status of the SSRF project.
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THPKF044 | The Improvement of NSRRC Linac for Top-up Mode Operation | electron, linac, power-supply, gun | 2374 | ||||||
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The performance of the 50 MeV linac at the National Synchrotron Radiation Research Center (NSRRC) was examined and has been improved recently. The major improved items were 1) adopting a command-charging scheme to replace the resonance charging for the linac modulator; and 2) gun electronics. As a result, the beam quality was improved in terms of its energy spectrum and stability. The correlation between the improvement of beam quality and component upgrading is analyzed. The influence of the beam quality improvement to the recently proposed top-up mode operation in 2005 will also be discussed in this report.
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THPKF046 | Feasibility Study of Constant Current Operation at TLS Storage Ring | injection, photon, insertion, insertion-device | 2380 | ||||||
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Several top-up experiments were carried out at various upgrade path of Taiwan Light Source. However, there were too many obstacles laid ahead of various stages to prevent the realization of top-up injection routinely. The small gap undulators, the requirement of small emittance operation and high current operation by SC cavity have promoted the top-up injection project to hightest priority. During last one and half years, a series of beam parameters measurement, subsystem checkout, installing various sensors, control program modification and hardware upgrade made the top-up injection more likely in routine operation. Discussions on the results of some measurements of booster and storage ring, the requirement of hardware upgrade and the future executable plan will be presented in this paper.
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THPKF064 | Status of Kharkov X-ray Generator based on Compton Scattering NESTOR | quadrupole, injection, laser, electron | 2412 | ||||||
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Nowadays the sources of the X-rays based on a storage ring with low beam energy and Compton scattering of intense laser beam are under development in several laboratories. In the paper the state-of-art in development and construction of cooperative project of a Kharkov advanced X-ray source NESTOR based on electron storage ring with beam energy 43 - 225 MeV and Nd:YAG laser is described. The layout of the facility is presented and main results and constructing timetable are described. The designed lattice includes 4 dipole magnets with combined focusing functions, 20 quadrupole magnets and 19 sextupoles with octupole component of magnetic field. At the present time a set of quadrupole magnet is under manufacturing and bending magnet reconstruction is going on. The main parameters of developed vacuum system providing residual gas pressure in the storage ring vacuum chamber up to 10-9 torr are presented along with testing measurement at NSC KIPT vacuum bench. The facility is going to be in operation in the middle of 2006 and generated X-rays flux is expexted to be of about 1013 phot/s.
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THPKF067 | Progress of the DIAMOND Storage Ring and Injector Design. | injection, booster, septum, coupling | 2418 | ||||||
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DIAMOND is a state of the art 3 GeV synchrotron light source that will be available to users in 2007. Considerable further progress has been made on the accelerator physics design of the storage ring, booster and other associated injector systems. Detailed analysis of injection processes, lifetime, coupling, instabilities, feedback systems and dynamic aperture have been undertaken driven by the procurement activity and the desire to fully understand all aspects of the accelerator's performance.
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THPKF070 | A Beam Based Alignment System at the CAMD Light Source | quadrupole, lattice, alignment, power-supply | 2427 | ||||||
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Beam based alignment is being applied to the CAMD light source. It is implemented by a flexible and versatile system of electronic shunts which are applied to each of the storage ring lattice quadrupoles. The essential design features of the electronic shunts are described as is the routine operation of the full system. The improvement to the corrected closed orbit from using the system is shown. Preliminary results are presented of the use of the shunts for correcting the lattice functions.
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THPKF071 | Linear Coupling and Lifetime Issues in the DIAMOND Storage Ring | coupling, quadrupole, emittance, sextupole | 2430 | ||||||
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In synchrotron light sources the correction of the linear coupling is an important issue related to the brightness of the photon beam and to the beam lifetime. The vertical emittance of the electron beam in the DIAMOND storage ring will be controlled using 168 skew quadrupoles embedded in the sextupoles of the ring. In this paper we report the linear coupling estimates for the expected misalignment errors and we compare the results of coupling correction with different correction strategies. The effect on lifetimes is also discussed.
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THPKF072 | Progress with the Diamond Light Source | vacuum, booster, injection, diagnostics | 2433 | ||||||
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Construction of Diamond, the UK?s new 3 GeV, 3rd generation synchrotron light source, is well underway and progressing in-line with the original target of starting storage ring commissioning in January 2006 and being operational for users in January 2007. Having completed the foundations, the main building works are now proceeding at their maximum rate. Most of the major machine components are also under construction, aiming towards the key target date of starting machine installation in September 2004. As well as reporting on the overall status, detailed design developments and component choices will be summarised. The results of tests of various prototype components, including magnets, vacuum vessels and girders, will also be presented.
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THPKF073 | CIRCE, the Coherent InfraRed CEnter at the ALS | radiation, laser, synchrotron, synchrotron-radiation | 2436 | ||||||
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CIRCE (Coherent InfraRed Center) is a new electron storage ring to be built at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (LBNL). The ring design is optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range. CIRCE operation includes three possible modes: ultra stable CSR, femtosecond laser slicing CSR and broadband SASE. CSR will allow CIRCE to produce an extremely high flux in the terahertz frequency region. The many orders of magnitude increase in the intensity is the basis of our project and enables new kinds of science. The characteristics of CIRCE and of the different modes of operation are described in this paper.
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THPKF088 | NSLS II: A Future Source for the NSLS | impedance, synchrotron, brightness, insertion | 2457 | ||||||
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The National Synchrotron Light Source at BNL was the first dedicated light source facility and has now operated for more than 20 years. During this time, the user community has grown to more than 2400 users annually. To insure that this vibrant user community has access to the highest quality photon beams, the NSLS is pursuing the design of a new ultrahigh brightness (~ 1E21) electron storage ring, tailored to the 0.3-20 keV photon energy range. We present our preliminary design and review the critical accelerator physics design issues.
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THPLT019 | Commissioning Results of the Multi Bunch Feedback System at SLS | feedback, diagnostics, kicker, betatron | 2508 | ||||||
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Within the frame of the project for a multi bunch feedback system for the Swiss Light Source (SLS), a new family of 500 MS/s analog to digital and digital to analog conversion boards with an 8 bit resolution has been developed, containing on board MUX and DEMUX circuitry to reduce data rates to approximately 20 MS/s using up to ten Front Panel Data Port (FPDP) ports. Using six quad processor DSP boards, full bandwidth bunch by bunch feedbacks in the transverse and longitudinal planes are set up to provide bunch by bunch correction kicks with a 2 nsec resolution. We report on the hardware setup and properties as well as feedback performance in the SLS storage ring.
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THPLT021 | A DSP-Based Fast Orbit Feedback System for the Synchrotron Light Source DELTA | feedback, booster, power-supply, quadrupole | 2514 | ||||||
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A DSP-based Fast Orbit Feedback (FOFB) system has been designed for the synchrotron light facility DELTA. DELTA consists of a 60 MeV linac, the ramped storage ring BoDo as full-energy injector and the 1.5 GeV storage ring Delta. BoDo and Delta have the same dipole, quadrupole and corrector magnet design, the same beam pipe design and the same BPM RF frontends, therefore BoDo was used as a testbed for the newly developed FOFB hardware and software. Using the fast corrector magnet power supplies of BoDo, the FOFB could damp orbit perturbations up to 90 Hz. The envisaged future use of the FOFB for the Delta storage ring will require either the partial or full replacement of the present slow (1 Hz bandwidth) Delta corrector power supplies, or additional fast power supplies with dedicated FOFB corrector magnets. A first test of the FOFB in Delta for local orbit stabilization at one beamline is in preparation. This paper presents the results of a successful test of the FOFB at BoDo, where it achieves a correction rate of 4 kHz for a global SVD-based feedback in both planes. The FOFB is based on the "DeltaDSP" VMEbus DSP boards that are also used for the BoDo betatron tune feedback.
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THPLT024 | Commissioning and Operation of the SLS Fast Orbit Feedback | feedback, photon, electron, booster | 2523 | ||||||
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The SLS Fast Orbit Feedback (FOFB) was successfully commissioned in 2003. Since November 2003 it runs during user operation of the accelerator. Taking into account 72 Digital Beam Position Monitors (DBPMs), the FOFB applies SVD-based global orbit corrections for 72 horizontal (x) and 72 vertical (y) correctors at a rate of 4 kHz, compared to ~0.5 Hz for the Slow Orbit Feedback (SOFB) that was used so far. While the SOFB was important for the elimination of orbit drifts due to temperature changes and slowly moving insertion device (ID) gaps, the FOFB is also able to damp orbit oscillations that are caused by fast changes of ID gaps or magnets, by ground and girder vibrations, 3 Hz booster crosstalk and power supply noise. This report presents experience from commissioning and user operation of the FOFB.
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THPLT025 | Using Visible Synchrotron Radiation at the SLS Diagnostics Beamline | radiation, synchrotron-radiation, synchrotron, diagnostics | 2526 | ||||||
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A diagnostics beamline has been set-up at the BX05 bending magnet of the SLS storage ring. It is equipped with a standard bending magnet front end, including two photon beam position monitors (PBPM) for determination of photon beam angle and position as well as a pinhole array monitor for online monitoring of beam size. The visual part of the dipole radiation is transported to an optical lab, where the temporal profile of the storage ring bunches can be measured with a minimal time resolution of 2 ps using a dual sweep, synchrocan streak camera. Simultaneously, beam size and coupling can be measured at 1.8 keV radiation energy with a zome plate monitor overcoming diffraction limitations. This paper describes the beamline design and summarizes the first experimental results.
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THPLT031 | Comparison of Rate Equation Models for Equilibrium Beam Parameters | scattering, electron, target, antiproton | 2544 | ||||||
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We calculate equilibrium beam parameters from the counteraction of intrabeam scattering (IBS), electron cooling (EC) and target interaction for typical beams in the GSI cooler storge ring ESR and in the proposed HESR. This work is complementary to kinetic modeling efforts at GSI. We developed an easy to use simulation tool that includes various models for the EC rates and the IBS rates, averaged of the detailed ring lattices. The obtained scaling of the equilibrium parameters with beam current and energy are compared with existing experimental data from the ESR and with kinetic simulation results for the HESR.
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THPLT038 | The Synchrotron Radiation Interferometer using Visble Light at DELTA | synchrotron, radiation, synchrotron-radiation, electron | 2565 | ||||||
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Synchrotron radiation sources such as DELTA, the Dortmund electron accelerator, rely on a monitoring system to measure the beam size and emittance with sufficient resolution. The resolution limits of the different types of optical synchrotron light monitors at DELTA have been investigated. The minimum measurable beam size with the standard synchrotron light monitor using visible light at DELTA is appr. 80 μm. Due to this limitation an interferometer was built up and tested using the same beamline in the visible range. A minimum measurable beam size of appr. 8 μm could be obtained, which gives an increased resolution of one order of magnitude with the new system.
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THPLT039 | SVD Based Orbit Correction Incorporating Corrector Limitations at DELTA | dipole, synchrotron, beam-losses, multipole | 2568 | ||||||
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Singular Value Decompostion (SVD) of the orbit response matrix has become an invaluable tool for orbit correction at storage rings worldwide. SVD based orbit correction has now been realised at DELTA, a 1.5 GeV electron storage ring. However, due to special orbit demands at DELTA and possibly by magnetic imperfections within the storage ring, we frequently have to face corrector limitations during the process of orbit correction. This work focuses on presenting an analytic algorithm on how to treat these limitations when seeking for an optimal SVD based orbit correction. In contrast to previously published methods, this approach is fairly easy to implement and does not afford an numerical solver. Concepts and results will be presented.
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THPLT043 | Development of a New Orbit Measurement System | damping, controls, synchrotron, vacuum | 2577 | ||||||
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Since DORIS III became a dedicated source for synchrotron radiation in 1993, the demands of the synchrotron-light-users concerning the beam position stability have permanently increased.In order to improve this stability, different measures have been adopted, all with success. The vacuum chambers have been renewed, since they were the source of quadrupole movement, which caused strong horizontal orbit distortion. In 2003 a new orbit position control was implemented, based on the ?Singular Value Decomposition? method. The position information comes from synchrotron light monitors, installed in the beam-lines, and from the orbit measurement system, which operates with a maximal measurement rate of 5Hz and a spatial resolution not less than 20μm. To satisfy the requirements for beam-position stability, the orbit measurement system has been further developed. The test stage is nearly finished and the new system will be installed soon. The orbit measurement rate will exceed 250Hz und the spatial resolution will be less than 2μm. In addition beam oscillations of up to 20Hz can be damped.
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THPLT045 | A more Accurate Approach to Calculating Proton Bunch Evolution under Influence of Intra-beam Scattering in a Storage Ring. | scattering, proton, synchrotron, background | 2583 | ||||||
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Some perturbations of discrete nature are known to influence the performance of a proton storage ring, contributing to parasitic background, decay of beam currents and bunch tail buildup. Such are, for example, intra-beam scattering and residual gas scattering .These processes are to a big extent described by existing analytical theory. The latter, employing a large amount of averaging, usually neglects effects arising from system nonlinearity. So, the motion of tail particles in the presence of a sufficiently nonlinear RF voltage under influence of intra-beam scattering strongly deviates from the average across the bunch and the analytical approach seems inadequate for it. To overcome this situation we have developed more accurate numerical methods for calculations of bunch evolution under influence of a rather broad class of jump-like perturbations. Here we present the computational algorithms and their application to assessment of coasting beam and proton background in HERA-p.
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THPLT068 | Transverse Bunch-by-bunch Feedback System for the SPring-8 Storage Ring | feedback, damping, injection, emittance | 2649 | ||||||
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A transverse bunch-by-bunch feedback system is developed for the SPring-8 storage ring. An analog de-multiplexer is developed to slice out every six-bunch signal for high-resolution 12-bit ADCs of clock frequency 85MHz, one-sixth of 508MHz RF frequency. Six commercial ADC-FPGA-DAC boards are used for processing the signal from the de-multiplexer. A custom FPGA board is used to multiplex the output signals from those boards. The feedback system is installed in the ring and working with the damping time of 0.5~2.5ms in 30kHz-254MHz and can suppress multi-bunch instabilities driven by impedances of resistive-wall of in-vacuum insertion devices and cavity HOMs at low chromaticity operation.
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THPLT089 | MATLAB Based TPSA Toolbox for the Particle Mapping Through Three-dimensional Magnetic Fields | insertion, insertion-device, focusing, quadrupole | 2703 | ||||||
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Based on the object-oriented programming of MATLAB, a truncated power series algebra (TPSA) toolbox has been developed. The TPSA toolbox as a differential algebra has been applied to realize the algorithm of particle mapping through three-dimensional magnetic field configurations. The capability of symbolic calculation by using this MATLAB-based TPSA toolbox can be used for the theoretical simulation and modeling in accelerator physics. Associated with the use of MATLAB in the control of machines, one can derive the real machine with a virtual machine model built in MATLAB. In this paper, the method of symplectic mapping of three-dimensional magnetic fields is introduced and the structure of TPSA toolbox is presented. Applications of TPSA toolbox in the symplectic mapping of three-dimensional magnetic fields are demonstrated as well.
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THPLT090 | The Operating of Digital Beam Position Monitor in NSRRC | closed-orbit, diagnostics, betatron, feedback | 2706 | ||||||
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The digital beam position monitors are configured to operation system in the NSRRC now. This integration includes of multi-channel access, channel calibration, gain control, and parameter control to meet various operation condition, perform functionality and performance evaluation. The programmability nature of DBPM system is essential for multi-mode high precision beam position measurement. The system will support high performance beam position, turn-by-turn beam position, tune and other diagnostic measurements. Control system interface was implemented to support the operation of DBPM system. T various aspects will be discussed and presented in this report.
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THPLT094 | Ordered Ion Beam in Storage Rings | ion, simulation, scattering, emittance | 2715 | ||||||
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The using of crystalline ion beams can increase of the luminosity in the collider and in experiments with targets for investigation of rare radioactive isotopes. The ordered state of circulating ion beams was observed experimentally at several storage rings. In this report a new criteria of the beam orderliness are derived and verified with BETACOOL code with using molecular dynamics technique. The sudden reduction of momentum spread observed on a few rings 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 ion rings which will have experimental programs for the study of crystalline beams. A new strategy of the cooling process is proposed which permits to increase the linear density of the ordered ion beam.
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THPLT108 | The Study of the Beam TAILS with the Optical Coronagraph | vacuum, simulation, scattering, collider | 2736 | ||||||
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Optical white-light Lyot coronograph is applied at the VEPP-4M collider to study the "tails" of the transverse beam profile. The device is used for investigation of the beam-beam effects.
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THPLT127 | Beam Diagnostics Systems for the Diamond Synchrotron Light Source | electron, linac, booster, synchrotron | 2765 | ||||||
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We present an overview of the diagnostics systems that will be implemented at the Diamond synchrotron light source. The aim of this paper is to give a complete picture of the systems to measure the quality of the electron beam from the injector through to the storage ring. We will show how we intend to measure the dimensions, the position and the time structure of the electron bunches. In addition, the instrumentation to measure the charge, the current and the emittance of the electron beam will be described. Finally, systems to provide accurate measurement of electron losses and the injection efficiency will be detailed.
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THPLT140 | Commissioning of BL 7.2, the New Diagnostic Beamline at the ALS | diagnostics, electron, radiation, photon | 2783 | ||||||
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BL 7.2 is a new beamline at the Advanced Light Source (ALS) dedicated to electron beam diagnostics. The system, which is basically a hard x-ray pinhole camera, was installed on the storage ring in August 2003 and the commissioning with the ALS electron beam followed immediately after. In this paper, the commissioning results are presented together with the description of the relevant measurements performed for the beamline characterization.
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THPLT141 | Operational Experience Integrating Slow and Fast Orbit Feedbacks at the ALS | feedback, insertion, insertion-device, pick-up | 2786 | ||||||
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A fast global orbit feedback system has been implemented at the ALS and is being used during user operation since this year. The system has two main purposes. The first is to meet the demands of some users for even improved (submicron) short term orbit stability. The second is to enable the use of more sophisticated insertion device compensation schemes (e.g. tune, beta-beating, coupling) for fast moving insertion devices like elliptically polarizing undulators, without deteriorating the orbit stability. The experience of routine user operation with the fast orbit feedback will be presented, as well as the overall feedback performance and how the integration issues with the already existing slow orbit feedback were solved.
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THPLT162 | Diagnosis of Coupling and Beta Function Errors in the PEP-II B-Factory | coupling, betatron, lattice, resonance | 2840 | ||||||
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The SLAC Control program has an automatic phase measuring system whereby the beta functions of the two storage rings are measured. This facility has recently been extended to measure coupling between the horizontal and vertical motion and to fit the measured values to their modes of propagation. This facility aids the diagnosis and correction of coupling and focusing errors.
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THPLT186 | Bunch Pattern Control in Top-up Mode at the SLS | feedback, controls, injection, diagnostics | 2885 | ||||||
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One of the crucial issues in the advanced third generation light sources is the bunch pattern control in the storage ring, where various filling patterns are of interests for different experiments. The most important step is to keep a uniform charge distribution over all (electron) bunches during the top-up operation. Such a bunch pattern control has been implemented at the Swiss Light Source (SLS). It provides a filling pattern with bunch-to-bunch fluctuation of a few percent. Since a dependency of the medium term orbit stability on the actual filling pattern was observed in the past, the stability could significantly be improved. Three major ingredients have made the implementation possible: precise timing system, flexible control system and sophisticated diagnostics. The method is being used in the user operation recently and proved to be reliable. This paper describes the hardware and software involved in the mentioned technique.
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FRXBCH01 | Novel Ideas and R&D for High Intensity Neutrino Beams | proton, target, factory, electron | 281 | ||||||
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Recent developments in neutrino physics, primarily the conclusive demonstration of neutrino oscillations in both atmospheric neutrinos and solar neutrinos, provide the first conclusive evidence for physics beyond the Standard Model of particle physics. The phenomenology of neutrino oscillations, for three generations of neutrino, requires six parameters - two squared mass differences, 3 mixing angles and a complex phase that could, if not 0 or pi, contribute to the otherwise unexplained baryon asymmetry observed in the Universe. Exploring the neutrino sector will requires very intense beams of neutrinos, and needs novel solutions.
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Video of talk
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Transparencies
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