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Type of presentation requested : Poster Speaker : C. C. Kuo Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1321  Vertical Emittance Control at BESSY P. Kuske, BESSY, Berlin In synchrotron radiation light sources like BESSY II the reduction of the vertical emittance can increase the brilliance of the photon beam, can improve the resolution of certain monochromators, and is required for the planned production of femto second light pulses based on bunch slicing [1]. On the other hand running the storage ring with only a few bunches favors a larger vertical emittance in order to reduce the particle density and Touschek losses. Thus flexible control of the vertical emittance is highly desirable. The paper describes the steps taken to accomplish this goal. The small vertical emittance is achieved by beam based alignment, analysis of the orbit response matrix in order to find suitable locations for skew quadrupole magnets, the minimization of the vertical dispersion, and the decoupling of the transverse planes by observing and correcting the local normal modes at 63 beam position monitors. In the single bunch mode the vertical emittance is increased by exciting an artificial difference coupling resonance with a time varying skew gradient field produced by strip lines. This approach has certain advantages over other techniques used for blowing up the beam. [1] S. Khan, private communication Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 27  Beam Matching Section for the Superconducting COSY Injector LINAC A. Lehrach, H. Jungwirth, R. Maier, S. Martin, R. Tölle, FZJ, Jülich As a new injector for the Cooler Synchrotron COSY in Jülich a superconducting LINAC is being designed and constructed to provide intense beams of polarized protons and deuterons [1]. Beam dynamics calculation have been carried out to find an optimized configuration for beam matching between RFQ and LINAC. Therefore several different field arrangements have been discussed. In this paper the results of the beam dynamics calculations are presented and the capability of the matching section is discussed. [1] Conceptual design report 'Superconducting Injector LINAC for the Cooler Synchrotron COSY', Forschungszentrum Juelich, Internal report (2001). Type of presentation requested : Poster Speaker : A. Lehrach Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1468  Measurement of the LNLS Electron Storage Ring Beam Acceptance L. Liu, T. Costa, LNLS, Campinas We describe a method to determine the parameters of the beam acceptance in phase space in a storage ring using basically a kicker and current measurement. We present and discuss the results of the measurements performed on the LNLS UVX electron storage ring. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 64  Emittance Exchange by Crossing a Coupling Resonance E. Metral, C. Carli, G. Cyvoct, M. Giovannozzi, G. Metral, R. Steerenberg, CERN, Geneva When the working point of a synchrotron is shifted across a secondorder difference resonance in the presence of weak linear coupling, it is possible to exchange the transverse emittances. This result goes beyond the classical theory, where only emittance sharing is predicted. Systematic experimental investigations of the phenomenon have been performed at the CERN PS Complex. In the PSBooster, the measurement of the horizontal emittance is hampered by the contribution of the momentum spread to the beam size through dispersion. Based on the new mechanism, the horizontal emittance was measured in the vertical plane, where no dispersion is present, thus improving the overall accuracy. In the PS, detailed measurements of the emittance exchange process were performed. In parallel, an analytical theory was derived. The agreement between theory and experimental results is remarkable. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1014  Low Emittance Lattice Upgrades for the Duke FEL Storage Ring (*) S. Mikhailov, V. Litvinenko, Y. Wu, DFELL, Durham In this paper we present two versions of possible upgrade of the lattice of the 1 GeV Duke FEL Storage Ring reducing horizontal beam emittance from existing 18 nm*rad to 1.4 nm*rad and 0.9 nm*rad respectively. One of proposed lattices reuses existing magnetic elements, another is based on completely new design. The use of combined function magnets with dipole, quadrupole and sextupole components allows us to keep the ring compact and fit it into existing footprint. We present the results of 2D and 3D magnet design and field simulations for such a magnet. Results for dynamic aperture simulations are also presented. We also discuss the choice of lattice cell and tune advances and the concept of local compensation of nonlinear aberrations. (*) This work is supported by the Dean of Natural Sciences (Duke University) Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 738  Degrees of Freedom Determination in Accelerator Physics Optimisation Problems Subject to Global Constraints A.S. Mueller, CERN, Geneva The determination of the number of degrees of freedom of a system is a common problem in physics. It is straightforward for the case of unbounded parameters. For global constraints cutting into the parameter space however, the determination is difficult. This problem occurs, for example, in the matching of beam lines where global constraints like aperture or maximum bend angle have to be respected. It is also relevant for fits of complex models to experimental data, where external information (e.g. positivity, maximum energy loss or measured momentum spread) is included in the form of constraints. This paper proposes a method to extract the effective number of degrees of freedom for a given system. Examples are discussed to illustrate the method. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1475  Simulation and Correction of the Closed Orbit Distortion for the New Lattice of SOLEIL* A. Nadji, SOLEIL, Orsay The SOLEIL lattice has been modified in order to satisfy the growing interest in the use of undulators as the privileged photon sources [1]. The sensitivity of the new optics to dipolar errors has been studied. The expected values of horizontal and vertical orbit distortions are calculated analytically using statistical formulae and computed with a tracking program (BETA) in order to take into account the effects of the sextupoles. The number and the location of beam position monitors and correctors have been revisited. As for the estimation of the errors, their correction is also performed both analytically (which is particularly interesting during the elaboration of a project) and numerically (which allows to control the restoring of the dynamic aperture).We report here the results of the correction, using SVD method, from a comparative study using a minimum necessary number of correctors and all the available ones. The dipolar correctors are coils installed inside sextupoles. Special attention is paid to the effect on the dynamic aperture of inevitable extra multipolar components introduced by these dipolar correctors. *work supported by Synchrotron SOLEIL [1] A modified lattice for SOLEIL with a larger number of straight sections, A. Nadji, P. Brunelle, J. M. Filhol and M. P. Level Shanghai Symposium on Intermediate Energy Light Sources, 2326 September 2001 Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1338  Analysis and Correction of Optical Asymmetry at the ESRF R. Nagaoka, L. Farvacque, ESRF, Grenoble The correction of optical asymmetry due to quadrupole errors is of great importance for the required beam quality at the ESRF. With the conventional orbit response matrix approach, effective quadrupole errors are extracted. Following the success of using the skew components obtained in this way with the offdiagonal matrix to correct the coupling, an online correction of optical asymmetry is attempted using a partial response matrix. Results are compared with the empirical correction of the nearest halfinteger resonances that has conventionally been performed. Resonance stopbands are computed at each stage on the basis of the obtained quadruple error distribution and their utilisation in the minimisation procedure is considered. A thousandturn BPM diagnostic implemented at the ESRF is used to measure independently the optical asymmetry. Attempts made to trace the origin of errors are also discussed. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1441  Electron Bremsstrahlung Characteristics Calculation Model for a Multilayer Conversion Target Placed in a Hyperbolic Magnetic Field A. Nesterovich, P. Alferov, V. Kudinov, A. Savostyanov, V. Smirnov, MEPhI, Moscow The description of an electron bremsstrahlung characteristics calculation model for a multilayer conversion target, placed in a hyperbolic magnetic field is presented. The bremsstrahlung characteristics at electron energy up to 300 MeV from 10layer copper target are obtained. The thickness of each layer is equal to 0,05 radiation length. Quadrupole magnetic triplets are located between layers. It is shown, that the bremsstrahlung source intensity with use of offered magnetic system grows almost in 1,8 times for registration angle equal to1O. For the numerical decision of equation of the charged particles movement in the magnetic field, given by a magnet, the linear difference method for a Koshi task approximation for first order ordinary differential equations system the was used. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1452  Possibility of an Electron Bremsstrahlung Output Increase by Use of a Conversion Target placed in a Focusing Magnetic Field A. Nesterovich, P. Alferov, V. Kudinov, Y. Pomazan, V. Smirnov, MEPhI, Moscow The dependences of bremsstrahlung output at electron energy about 100300 MeV upon multilayer target, placed in a focusing magnetic field, thickness are presented. The system suggested is intended for an intensive bremsstrahlung flow formation on objects, which are removed from radiator on significant distance. Such radiator, in particular, can be used at monitoring the Earth atmosphere from space and at sounding planets with the help of space vehicles. It is shown, that the bremsstrahlung output from 10layer copper target, placed in a focusing magnetic field, exceeds in 3 times the one from an optimum target for a registration angle of 10. The magnetic field influence on bremsstrahlung angular distribution width is investigated. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1053  Measurement of XY Coupling at I.P using Turnbyturn BPM Y. Ohnishi, Y. Funakoshi, M. Tejima, M. Tobiyama, KEK, Ibarakiken We have measured the xy coupling of the interaction point (I.P) at KEKB. The horizontal or vertical betatron oscillations can be measured by a turnbyturn BPM in the laboratory coordinate system when a normal mode is excited by a shaker with tune frequency. A harmonic analysis has been performed to measure the xy coupling parameters and compared with a measurement from single kick orbit. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1478  New Stability Regions for Periodically Focused Particle Beams* R. Pakter, ULBRA, Canoas; F. Rizzato, UFRGS, Porto Alegre A key aspect of periodically focused beams is their stability properties. Previous studies revealed that above a certain threshold of the focusing field strength the matched (equilibrium) solution looses stability, imposing severe limitations to the practical use of periodical focusing. In this paper, we perform a detailed stability analysis of periodically focused intense particle beams based on the beam envelope equation. It is shown that although the original matched solution analyzed in previous works becomes unstable and eventually vanishes as the focusing field strength increases, stability is recovered for yet larger fields because new matched solutions emerge. The scenario as one increases the focusing field is thus not the existence of a single threshold above which confinement is impossible, as believed so far, but the existence of regions of stability interrupted by gaps where the matched solution either becomes unstable or completely absent [1]. We also show that one can effectively focus beams to tighter radii using the new stable matched solutions. Results are validated with selfconsistent simulations. * Work supported by CNPq, Brazil. [1] R. Pakter and F. B. Rizzato, Phys. Rev. Lett., 87, 044801 (2001). Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 1720  An Isopath Achromatic Bending Section for Multicharge Ion Beam Transport at ISACII M. Pasini, R. Laxdal, TRIUMF, Vancouver The ISACII post accelerator at TRIUMF has been optimized to allow the simultaneous acceleration of ions with multiple charge states after stripping to preserve beam intensity of the exotic species. Bending sections, required to provide charge selection, fit building layouts or to transport beam to the experimental station, are constrained to have equal path length (isopath condition) for all charge states to maintain bunch structure. In addition they have to maintain a high order of achromaticity to prevent transverse emittance growth. An isopath system of four optics cells with proper symmetry conditions will fulfill the achromatic condition to high order. In the case of very low beam intensities such as for radioactive beams in which small losses are still acceptable, it is convenient to consider systems with only two cells, which don't give the exact solution, but still maintain a reasonable beam quality. We present here a comparison between the four and two cell systems applied to the ISACII case in which the range of charges transported is ±5% from the reference one. Type of presentation requested : Poster Classification : [D01] Beam Optics  Lattices, Correction Schemes, Transport 957  Coupling Analysis and Correction at RHIC F. Pilat, J. BeebeWang, W. Fischer, V. Ptitsyn, T. Satogata, BNL, Upton, Long Island, New York Coupling correction at RHIC has been operationally achieved through a twostep process: using local triplet skew quadrupoles to compensate coupling from rolled lowbeta triplet quadrupoles, and minimizing the tune separation and residual coupling with orthogonal global skew quadrupole families. An application has been developed for global correction that allows skew quadrupole tuning and tune display with a choice of different tune measuring techniques, including tunemeter, Schottky and PLL. Coupling effects have been analysed by using 1024turn turnbyturn (TBT) information from the beam position monitor (BPM) system. Injection decoherence data allow the reconstruction of the offdiagonal terms of the transfer matrix, a measure of global coupling at injection. At both injection and storage energies, coordination of tunemeter kicks with TBT acquisition at 322 BPMs in each ring allows the measurement of local coupling at all BPM locations. 