| Paper | Title | Other Keywords | Page |
|---|---|---|---|
| TUPC016 | Status of the ATF2 Lattices | lattice, quadrupole, sextupole, optics | 1027 |
|
|||
| The latest status for the ATF2 Nominal and Ultra-low beta lattices designs obtained to minimize the detrimental effect of the measured multipoles are presented in this paper. A set of correction knobs for the most important aberrations at the IP have been obtained for both lattices in order to perform the tuning under realistic imperfections. Starting from the tuned ATF2 Nominal lattice a squeeze sequence reducing betay is performed to reach the ultra-low beta lattice. Tuning results are shown for both options. | |||
| TUPS094 | Girder and Support System for PLS-II Project | dipole, storage-ring, alignment, quadrupole | 1759 |
|
|||
| Pohang Accelerator Laboratory (PAL) is planning to upgrade the Pohang Light Source (PLS) which is a 3rd generation light source operating since 1995. We have designed a new steel magnet girder using new schemes to achieve long-term mechanical stability, vibration suppression and precision adjusting system. Each half cell of girder is composed of three pieces, two multipole magnet girder(MMG) and one dipole magnet girder(DMG). The storage ring girders consist of 48 multipole magnet girders and 24 dipole magnet girders. The new girder systems have been fabricated and tested. Recently the girders have been installing and testing the moving mechanism in the storage ring. In this report, the design consideration for the PLSII girder and support systems are reported. | |||
| TUPZ039 | Modelling of the AGS Using Zgoubi - Status | dipole, quadrupole, simulation, resonance | 1897 |
|
|||
| Models of the Alternating Gradient Synchrotron, based on stepwise ray-tracing methods using both mathematical modelling or field maps so to represent the optical elements, including the siberian snakes, are being developed based on stepwise ray-tracing numerical tools. The topic is introduced in earlier PAC and IPAC publications, a status is given here. | |||
| WEPC035 | Double Mini-Betay Lattice for TPS Storage Ring | lattice, emittance, dynamic-aperture, quadrupole | 2082 |
|
|||
| Based on our previous design of double mini-betay optics in one 12-m straight section, NSRRC plan to implement the double mini-betay lattice in three 12-m straight sections in TPS storage ring. Those three locations chosen for double mini-betay lattice still retain the symmetry of accelerator lattice. The two symmetric minima of the vertical beta function will be created in the center of three 12-m straight sections, respectively. We strived to obtain a linear lattice such that there is no significant increase in the natural emittance. Efforts were devoted to optimize the nonlinear beam dynamics with various simulation tools. Preliminary results will be reported. | |||
| WEPC060 | Magnetic Field Description in Curved Accelerator Magnets using Local Toroidal Multipoles | dipole, antiproton, synchrotron, quadrupole | 2154 |
|
|||
| Any introduction on beam dynamics describes the field homogeneity of the accelerator magnets using local derivatives. These are then typically described as plane circular multipoles or 2D harmonics; solutions to the potential equation. The high current operation, foreseen for SIS100 accelerator of FAIR, requires an in detail understanding of the different beam effects, driven by the resonance of the magnets. Therefore different multipole sets were developed and are now finalised in the Local Elliptic Toroidal Multipoles. These are a first order approximation while the plane circular ones are a zero order one in the inverse aspect ratio. | |||
| WEPC061 | ENC Interaction Region Separation Dipoles | dipole, solenoid, electron, sextupole | 2157 |
|
|||
| The Electron Nucleon Collider (ENC) is proposed as an upgrade of the High Energy Storage Ringe of the FAIR. The beams are separated by two dipoles, mounted closely to the intraction point; surrounded by the detectors. Hence these magnetsmust provide sufficient field quality but be slim to be transparaent to the secondary particles. Further these must be air coil magnets due to the detector solenoid field of 2T. We present the 3D optimised magnet next to a first design of the mechanical restraint structure and a concise description for the field distortion leaking into the detector. | |||
| WEPC077 | Beam Based Measurements with the Modified Wigglers in DAΦNE | wiggler, closed-orbit, octupole, simulation | 2196 |
|
|||
| A novel idea to minimize the odd high order non-linearities in periodic magnets has been presented in other articles in the past. The optimization of this method on the wigglers of the main rings in DAΦNE has been performed by means of multipolar and tracking analysis. After the magnetic measurements on a spare wiggler confirmed the magnetic model used to optimize the DAΦNE wigglers, all the insertion devices in the main rings have been modified accordingly. In fall last year tune variation measurements as a function of closed orbit bumps around the wigglers confirmed the validity of the method. In this paper the beam based measurement results with the new configuration are discussed and compared with those obtained in the previous configurations. | |||
| WEPC085 | Multipole Fringe Fields | dipole, quadrupole | 2211 |
|
|||
| When creating an initial model of an accelerator, one usually has to resort to a hard edge model for the quadrupoles and higher order multipoles at the start of the project. Ordinarily, it is not until much later on that one has a field map for the given multipoles. This can be rather inconvenient when one is dealing with particularly thin elements or elements which are rather close together in a beamline as the hard edge model may be inadequate for the level of precision desired. For example, in the EMMA project, the two types of quadrupoles used are so close together that they are usually described by a single field map or via hard edge models. The first method has the desired accuracy but was not available at the start of the project and the second is known to be a rough approximation. In this paper, an analytic expression is derived and presented for fringe fields for a multipole of any order with a view to applying it to cases like EMMA. | |||
| WEPO019 | Magnetic Model of the CERN Proton Synchrotron Main Magnetic Unit | focusing, synchrotron, proton, dipole | 2439 |
|
|||
| The CERN Proton Synchrotron (PS) will remain one of the key elements of the Large Hadron Collider (LHC) injector system for the next 20-25 years. Tuning the machine characteristics to the requirements for the LHC and its upgrades will require the establishment of an accurate magnetic model of the PS combined-function magnets, which is the subject of this paper. In the scope of this research, a detailed 2D quasi-static analysis of the PS magnets was performed, which allowed to investigate the magnetic field evolution and the contribution of separate magnet circuits at different field levels. An experimental validation of this new model was carried out through ad-hoc field measurements machine studies iterated with an optical model of the PS machine to recreate the measured optical parameters of the beam. | |||
| WEPO020 | Magnetic Field Inspection and Analysis of Multipole Lattice Magnets using a Rotating-coil Measurement System* | quadrupole, storage-ring, sextupole, synchrotron | 2442 |
|
|||
| A precise rotating-coil measurement system (RCS) was constructed to characterize the field quality and field center of multipole lattice magnets of Taiwan Photon Source (TPS). The mechanical center of magnets is determined by the two references of the magnet-feet and the RCS system is used to characterize the field center. The location of the magnetic field center is quantitatively accurate to better than 20 micro-meter in the horizontal direction; the granite support height of the RCS system is accurate within 5 micro-meter after artificial polishing. The measurement reproducibility of the field center was better than 10 micro-meter when the magnets were reinstalled. The relative accuracy of the multipoles components is better than 2×10-5. This paper reports the details of the bench construction and the unit composition. The field center with RCS measurement will be compared and discussed with the 3D-coordinate-measuring machine. The multipole errors obtained from RCS will be compared with a Hall-probe measurement system. | |||
| WEPO024 | Design and Operation Parameters of the Superconducting Main Magnets for the SIS100 Accelerator of FAIR | dipole, quadrupole, sextupole, ion | 2451 |
|
|||
| SIS100, the worlds second large scale synchrotron for ion research, will use superferric magnets. The dipoles are of the window frame type, whose aperture was chosen as an optimum balance between the achievable field quality and AC losses at cryogenic temperatures. Analogous design optimisation was done for the quadrupole and corrector magnets as well. We present the design of the main magnets, estimate their operation parameters and define the crucial aspects to be experimentally analysed before series production, e.g. precise magnetic end field optimisation. | |||
| WEPZ009 | Parametric-Resonance Ionization Cooling in Twin-Helix | resonance, quadrupole, simulation, betatron | 2784 |
|
|||
|
Funding: Supported in part by DOE SBIR grant DE-SC0005589. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a high-luminosity muon collider. For the implementation of PIC, we developed an epicyclic twin-helix channel with correlated optics. Wedge-shaped absorbers immediately followed by short rf cavities are placed into the twin-helix channel. Parametric resonances are induced in both planes using helical quadrupole harmonics. We demonstrate resonant dynamics and cooling with stochastic effects off using GEANT4/ G4beamline. We illustrate compensation of spherical aberrations and benchmark COSY Infinity, a powerful tool for aberration analysis and compensation. |
|||
| THPC153 | Recent Progress in Insertion Devices at the ESRF | undulator, insertion, insertion-device, quadrupole | 3245 |
|
|||
| Insertion Device activities at the ESRF are presently driven by the upgrade of more than ten beamlines. The concept of canted undulators is part of the requirements in a number of cases. Permanent Magnet Steerers (PMS) will be used to create canting angles of up to 5.4 mrad. The magnetic structure of PMS has been fully optimized to minimise space occupancy and magnetic perturbations induced on neighbouring undulators. The measured field quality of PMS recently constructed will be presented. The development of undulators dedicated to high photon energy is still being pursued. Following on from the successful operation since 2008 of a first Cryogenic Permanent Magnet Undulator (CPMU) installed in the ID6 beamline, a second device has been constructed. This 2 m long device has a period of 18 mm and will be operated at 145 K. The field measurements at cryogenic temperature are discussed hereafter. | |||
| THPC156 | Performance of the PETRA III APPLE II Undulator | undulator, storage-ring, closed-orbit, optics | 3254 |
|
|||
| A 5m-long APPLE II undulator has been built in collaboration between Helmholtz-Zentrum Berlin and DESY Hamburg. Magnetic field measurements after the final shimming in the laboratory are presented. The device has been installed in the storage ring and machine studies have been performed. The tune shifts in the elliptical and the inclined mode are in agreement with predictions from theory. The dynamic field integrals have successfully been minimized in the storage ring with so-called L-shims (rectangular iron sheets) which are placed at the undulator center at the magnet edges. | |||
| THPC170 | Magnetic Characterization of FEL-2 Undulators for the FERMI@Elettra Free-electron Laser | undulator, FEL, sextupole, quadrupole | 3296 |
|
|||
| Kyma Srl is the spin-off company of Sincrotrone Trieste, Elettra laboratory, set up in 2007 together with the two industrial partners Cosylab d.d. and Euromisure SpA, in order to design and manufacture the undulators for the FERMI@Elettra project in Trieste, Italy. The insertion devices, for FEL-2 line, manufactured and characterized so far are the following: Modulator, 3.2 m linearly polarized undulator, three 55.2 mm APPLE-II variable polarization undulators, each 2.4 m long and six 34.8 mm APPLE-II undulators also each 2.4 m long. All the above devices have been characterized, both from the mechanical and the magnetic point of view. The measured parameters are in good agreement with the design values. This paper presents the most relevant changes in design from FEL-1 to FEL-2 line and results of the magnetic measurements carried out on all the above undulators. | |||
| THPC177 | Field Correction Results from NSRRC Elliptically Polarized Undulator 46 | kicker, undulator, electron, synchrotron | 3317 |
|
|||
| Elliptically polarized undulator (EPU) is a common insertion device to use in storage ring in order to provide circular polarization. The field correction is an essential step for EPU construction, and it can prevent the photon flux reduction from idea case and electron beam trajectory and exit angle from EPU. The conventional field correction method is tedious works and strongly based on experiences. An initial state of NSRRC EPU46 has phase error over 40 degrees, and many difficulties on field correction to reduce the phase error under 5 degrees. This paper will describe the detailed magnetic field correction process and practical results from in NSRRC EPU. | |||
| THPS031 | The Beam Expander System for the European Spallation Source | target, octupole, quadrupole, proton | 3487 |
|
|||
| At the European Spallation Source (ESS), neutrons are produced by high energy (2.5 GeV) protons impinging on a target. The lifetime of the target is highly dependent on the beam footprint. In general, the lower the average current density, the longer the lifetime of the target will be. A detailed study of two different expander systems suggested to be used to obtain the desired beam footprint has been undertaken. For reference, a system of quadrupole defocusing is used. The two systems under study are expansion of the beam by magnetic multipoles and raster scanning (painting) of the narrow linac beam over the target area. The designs, specifications, and comparative risks of the three systems will be described. | |||
| THPZ006 | SuperKEKB Interaction Region Modeling | solenoid, quadrupole, focusing, lattice | 3690 |
|
|||
| In the SuperKEKB interaction region(IR) design, the beam-line intersects solenoid-axis with large angle and the superconducting final focusing quadrupole magnets are installed into each beam-lines without iron-shield. Because of these features, the emittance and dynamic aperture evaluation have to consider the solenoid fringe field and the leakage multipole field of another beam-line magnet, respectively. The IR lattice modeling and the magnetic field handling of both solenoid and multipole field would be reported in this article. | |||