NSRRC, Hsinchu
An in-vacuum undulator with a room-temperature permanent magnet and a superconducting wiggler has become a mature technology and is widely used; it can adopt a short-period length in a medium-energy facility to provide an enhanced photon flux in the hard x-ray region. A cryogenic permanent magnet is applicable for an in-vacuum undulator to enhance the remanence field (Br) and the coercivity force. In future, a cryogenic permanent-magnet undulator and a superconducting wiggler will become mainstream to fulfill a user's requirement of a discrete and a continuous spectrum, respectively, but superconducting technology with HTS wires will have the best potential for the development of insertion devices after the next decade. HTS bulk magnets with magnet flux density 17 T are applicable even for a superconducting undulator; such an undulator can decrease the period length to about 10 mm. A small magnet gap with an extremely- short-period length (about 5 mm) has been studied with a stacked-layer of thin HTS tapes for a superconducting undulator. This report is a review to describe the current and future developments of insertion devices for a medium-energy storage ring and FEL facility.
CLS, Saskatoon, Saskatchewan
Storage rings require corrector magnets for a variety of tasks. Foremost are small dipole magnets for both horizontal and vertical correction. In light sources, for example, other corrector magnets are needed to compensate for the effect of changing insertion device operation points. These can include quadrupole, skew quadrupole, sextupole and skew sextupole corrections. As well octupole magnets may be desirable to improve dynamic aperture in small emittance lattices. One magnet can perform all these tasks. This is achieved by having separate windings with separate power supplies on an octopole yoke. The simultaneous excitation of any combination of modes can be achieved through superposition. Corrections are necessarily limited to avoid saturation effects that will degrade the superposition.
BNL, Upton, Long Island, New York
CERN, Geneva
IR4 is a potential candidate for the installation of crab cavities in the CERN Large Hadron Collider. In this paper we present several operational scenarios in which the effect of the kick imparted by the cavity is enhanced by performing a dynamic unsqueeze of the beta function at collision energy. Linear optics, power supply requirements, beam aperture and finally potential luminosity increase studies will be discussed in order to rank and assess the feasibility of the various options.
INFN/LNL, Legnaro (PD)
Torino University, ., Torino
INFN-Torino, Torino
In order to validate the tuning and stabilization procedures established for the IFMIF RFQ, a campaign of low power tests on an aluminum real-scale RFQ built on purpose has been carried out. Such campaign consisted of the determination of mode spectra, the measurements of the electric field distribution with bead pulling technique, and the implementation of the tuning procedure. The main outcomes and results obtained are reported in the article.
KEK, Ibaraki
Sudden decrease in the beam lifetime is sometimes observed in many electron storage rings. Such an event has been commonly attributed to dust trapping, but its mechanism has not been entirely elucidated yet. Our recent research at PF-AR has shown that trapped dust with certain conditions can be visually observed by video cameras, and the recorded movies revealed that the trapped dust moved longitudinally. In addition, the light emission from the dust indicated that its temperature reached 1000 K or more. Thus, direct observation of trapped dust has been proved to be an effective way to investigate the dust trapping mechanism. We have carried on this research with advanced cameras, such as high-sensitivity or high-speed cameras, and the results will be presented.
CERN, Geneva
IHEP Protvino, Protvino, Moscow Region
TRIUMF, Vancouver
The LHC has two dedicated cleaning insertions: IR3 for momentum cleaning and IR7 for betatron cleaning. The collimation system has been specified and built with tight mechanical tolerances (e.g. jaw flatness ~ 40 μm) and is designed to achieve a high accuracy and reproducibility of the jaw positions. The practically achievable cleaning efficiency of the present Phase-I system depends on the precision of the jaw centering around the beam, the accuracy of the gap size and the jaw parallelism against the beam. The reproducibility and stability of the system is important to avoid the frequent repetition of beam based alignment which is currently a lengthy procedure. Within this paper we describe the method used for the beam based alignment of the LHC collimation system, its achieved accuracy and stability and its performance at 450GeV.
CERN, Geneva
Background and loss rates vary when beams are brought into collisions in the LHC and when the beam separation is varied during luminosity scans. We report on the first observations in the early LHC operation. The observed effects are analyzed and compared with models and simulation.
SLAC, Menlo Park, California
A new method, using the parabolic equation (PE), for the calculation of both high-frequency and small-angle taper (or collimator) impedances is developed in [1]. One of the most important advantages of the PE approach is that it eliminates the spatial scale of the small wavelength from the problem. As a result, the numerical solution of the PE requires coarser spatial meshes. We developed a new code based on Finite Element Method (FEM) which can handle arbitrary profile of a transition. As a first step, we completed and benchmarked a two-dimensional code. One of the important advantages of the code is its fast execution time.
ASCo, Clayton, Victoria
Melbourne
The Australian Synchrotron storage ring must maintain a stable electron beam for user operations. The impedance characteristics of the storage ring can give rise to instabilities that adversely affect the beam quality and need to be well understood. Collective effects driven by the resistive wall impedance are particularly relevant at the Australian synchrotron and their strengths are enhanced by small gap insertion devices, such as IVUs. This study will explore the impedance issues identified in the Australian Synchrotron storage ring and current mitigation techniques.
PAL, Pohang, Kyungbuk
In 1994, ESRF in Grenoble opened the era of third-generation light sources, and the first batch of third-generation machines immediately followed with ALS, Elettra, TLS, PLS, and Spring-8 in hard and soft X-ray regimes. For high brightness, these machines adopted a low-emittance storage-ring lattice and many straight sections for advanced undulators. With ever-growing user demands from materials science to life science research, many more facilities followed in this decade. The machine operations dramatically improved for more effective user services, along with technological advances in advanced diagnostics and controls, survey and alignments, top-up injections, super-conducting cavities, and in-vacuum undulators. There are now about 70 light sources in the world, and important scientific discoveries are driven from these facilities, including research resulting in a few Nobel Prizes. In this paper, we review the advancement of these third-generation machines.
ISA, Aarhus
At Aarhus University in Denmark, a new synchrotron radiation source is being built. The 46-m circumference storage ring with 6-fold symmetry will operate at 580 MeV to produce bright UV and soft x-ray radiation. The storage ring will have a horizontal emittance of around 10 nm. Four straight sections will be available for insertion devices including a 12-pole wiggler with a field of 2 Tesla. ASTRID2 will operate in top-up mode with electrons from the present storage ring ASTRID, used as a booster. The insertion devices will have a strong influence on the lattice, and studies of dynamical aperture and compensation of tunes and beta beat will be presented. Also injection simulations will be given. The technical layout with details about magnetic arrangements on girders will be shown, including the vacuum system with extensive use of NEG. A 105 MHz RF system is being built together with a new LLRF system. At present, most major components have been ordered, and first injection will take place in the first half of 2011.
ESRF, Grenoble
After 15 years of highly successful user operation, the Council of the ESRF are funding an ambitious 7 year upgrade programme (2009-2015) of the European Synchrotron Radiation Facility. In this context the accelerator complex will benefit from a number of upgrades. Several insertion device straight sections will be lengthened from five to six meters. The beamline scientific capacities will be increased by operating some straight sections in the canting geometry. New insertion devices will be built to fulfill the requirements of the scientific programme. The RF system also faces a major reconstruction with the replacement of some klystron based transmitters by high power solid state amplifiers and the development of HOM damped cavities operating at room temperature. The orbit stabilisation system system will be renovated. This paper reports on the present operation performances of the source, highlighting the recent development, as well as the advancement of the upgrade projects.
CELLS-ALBA Synchrotron, Cerdanyola del Vallès
The new 3rd generation synchrotron radiation source ALBA built nearby Barcelona is planned to start operation in 2010 with several different insertion devices installed in the storage ring either from the beginning or within the first year of operation. The list of first insertion devices includes: 2 planar PPM SmCo in-vacuum undulators with the period of 21.6 mm; 2 Apple-II type PPM NdFeB undulators with the periods of 62.36 and 71.36 mm respectively; 1 superconducting planar wiggler with the period of 30 mm and a maximum field of 2.1 T, and a 1 conventional wiggler with the period of 80.0 mm and a maximum field of 1.74 T. The emitted light of these IDs covers wide spectral range extending from hard X-rays to UV. Pre-design of the IDs was done by ALBA, but manufacturing has been outsourced. Production is now finished and they have been tested with magnetic measurements. The paper will present the final as build magnetic designs as well as the main results of magnetic measurements performed on the manufactured devices.
Ankara University, Faculty of Sciences, Tandogan/Ankara
The Turkish Accelerator Center (TAC) is a project for accelerator based fundamental and applied researches supported by Turkish State Planning Organization (TSPO). The proposed synchrotron radiation facility of TAC was consisted of 3.56 GeV positron ring for a third generation light source. In the first study, it was shown that the insertion devices with the proposed parameter sets produce maximal spectral brightness to cover 10 eV - 100 keV photon energy range. Now, in this study it is considered that the electron beam energy will be increased to 4.5 GeV, in order to obtain more brightness light and wide energy spectrum range, also the beam emittance reduced to 1 nm.rad.
Diamond, Oxfordshire
Diamond Light Source has delivered beam for users exclusively in top-up mode since the end of October 2008. In this mode, a small number of single bunches are injected into specific buckets of the storage ring every ten minutes in order to maintain a constant beam current and fill pattern. During top-up the storage ring current is held within a window of approximately 1.5mA around the target current, generally 250mA, for a variety of fill patterns, including a two-thirds storage ring fill and a hybrid fill in which an intense single bunch is added to the normal fill pattern. Top-up has run continuously for several days on many occasions, with injection efficiency into the storage ring of typically 60%-95% even with 10 in-vacuum insertion device in operation with a permitted minimum gap of 5 mm. The effect of insertion devices, pulsed magnet stability and storage ring beam optics on top-up reliability and performance is examined, and the development of tools for the control of top-up and storage ring fill is detailed.
LBNL, Berkeley, California
The Advanced Light Source is one of the earliest 3rd generation light sources. With an active upgrade program it has remained competitive over the years. The latest in a series of upgrades is a lattice upgrade project that was started in 2009. When it will be completed, the ALS will operate with a horizontal emittance of 2.2 nm and an effective emittance of 2.6 nm. Combined with the high current of 500 mA and the small vertical emittance the ALS already operates at this upgrade will keep it competitive for years to come. The presentation will present the status of the upgrade, including beam dynamics studies and lattice optimizations as well as the magnet design and status.
Melbourne
ASCo, Clayton, Victoria
The Australian Synchrotron storage ring has a resistive wall instability in the vertical plane. Presently this instability is being controlled by increasing the vertical chromaticity. However new in-vacuum insertion devices that significantly increase the ring impedance may demand chromatic corrections beyond the capabilities of the sextupole magnets. A transverse bunch-by-bunch feedback system has been commissioned to combat the vertical instability* and provide beam diagnostics**. A high frequency narrow band mode that could not be damped was initial encountered with IVUs at minimum gap preventing the system from being implemented during user beam. Tuning of the bunch fill pattern, the digital filters and mapping out the system response lead to a configuration for user mode operations.
* Spencer, M.J. et. al. EPAC'08, Genoa, Italy
** Peake, D.J. et. al. PAC'09, Vancouver, Cananda
Diamond, Oxfordshire
We present our observations of the medium term and long term stability of the photon beams at Diamond Light Source. Drift of the Electron Beam Position Monitors results in real X-ray beam movements, observed by both Front End X-ray Beam Position Monitors and beamline scintillator screens on some beamlines. We discuss how we are using these diagnostics tools to measure and characterise the drift. Medium term movements related to top-up cycles are seen, believed to be caused by changes to single bunch charge, and the long term drift of the electron beam position over several days and weeks is examined. A slow feedback system using X-ray Beam Position Monitors has been shown to successfully correct this drift. The results of these trials are presented.
Muons, Inc, Batavia
CLASSE, Ithaca, New York
Superconducting RF (SRF) systems typically contain unwanted frequencies or higher order modes (HOM). For storage ring and linac applications, these higher modes must be damped by absorbing them in ferrite and other lossy ceramic materials. Typically, these absorbers are brazed to substrates that are strategically located, often in the drift tubes adjacent to the SRF cavity. These HOM loads must have broadband microwave loss characteristics and be robust both thermally and mechanically, but the ferrites and their attachments are weak under tensile and thermal stresses and tend to crack. Based on existing work on HOM loads for high current storage rings and for an ERL injector cryomodule, a HOM absorber with improved materials and design will be developed for high-gradient 750 MHz superconducting cavity systems for storage ring and linac radiation sources. This work will build on novel construction techniques to maintain the ferrite in mechanical compression without brazing. 750 MHz RF system designs will be numerically modeled to determine the optimum ferrite load required to meet broadband loss specifications.
CLS, Saskatoon, Saskatchewan
The Canadian Lightsource is a 2.9 GeV 3rd generation lightsource in Saskatoon, Canada. The latest expansion of operations includes adding 4 insertion devices in 2 straight sections. These devices will include a hybrid permanent magnet wiggler, an in-vacuum undulator and 2 APPLE-II type undulators. The 4 m long elliptical APPLE-II IDs will cover overlapping photon energy ranges of 15-200eV and 200-1000eV. These devices will be installed adjacent to one another in the same straight with the magnet arrays mounted on one support structure and a horizontal translation system to allow users to select one device at a time for use on a single beamline. The 2nd straight will include the hybrid wiggler and in-vacuum undulator in a 3 magnet chicane. The wiggler is designed to supply photons for a center beamline and a side beamline accepting radiation 5 mrad off of the centerline of the radiation fan. The critical energy of photons emitted of the sideline are >90% of the critical energy on the centerline. An 8 mrad center chicane magnet separates the photons of the undulator from the wiggler beamlines allowing for 3 beamlines operating with 2 IDs in a single straight section.
Danfysik A/S, Jyllinge
Danfysik A/S has built a cryogenic in-vacuum undulator for Diamond Light Source, with a period length of 17.7 mm and an effective K of 1.7 at cryogenic temperatures. The undulator is hybrid-type, with Vanadium Permendur poles and NdFeB poles. In order to verify the performance of the device under cryogenic conditions, an in-vacuum measuring system is required. We present the magnetic measurements at room temperature and under cryogenic in-vacuum conditions. The magnet assembly cannot be baked, due to a choice of high-remanence, low coercivity magnet grade. We discuss the vacuum performance of the undulator.
ESRF, Grenoble
An important upgrade of the ESRF is planned from 2009 to 2016. It is mainly driven by the improvement of beamlines performances and capacity. On the storage ring side, the length of the straight sections will be increased from 5 m to 6 m with a possible further extension to 7 m. These long sections will provide a higher photon flux, and it will allow the installation of canted undulators. The length of the insertion devices (ID), such as revolver undulators and in-vacuum undulators, will be modified to fit the first upgraded beamline sections. The resulting implication on the length of new IDs will be presented. The concept of canted undulators is a proposed optional feature. It will rely on novel permanent magnet chicane providing a maximal separation angle of 5.4 mrad while keeping short distance between canted undulators. Magnetic chicane magnets with low fringe field and homogeneous longitudinal field integral have been designed. The developed magnets will be presented.
Karlsruhe Institute of Technology (KIT), Karlsruhe
Precise measurements of the magnetic properties of conventional, i.e., permanent magnet based insertion devices has undergone tremendous improvements over the past 10 to 15 years and initiated a new era in synchrotron light sources worldwide. A similar breakthrough is now necessary in the field of superconducting insertion devices. In this contribution we describe the planned instrumentation to perform magnetic measurements of the local field, the field integrals and the multipole components of superconducting undulator coils in a cold invacuum (cryogen free) environment.
RIKEN/SPring-8, Hyogo
PSI, Villigen
JASRI/SPring-8, Hyogo-ken
The cryogenic permanent magnet undulator (CPMU) is an insertion device in which permanent magnets are cooled down to cryogenic temperature (CT) to improve the magnetic performances. Although CPMUs are realized by a slight modification of in-vacuum undulators (IVUs), we have several technical challenges to be overcome. Among them, the most important one is how to ensure the magnetic performance, in other words, how to measure the magnetic field at CT, and how to correct it if necessary. A new method of the phase-error correction has been proposed at SPring-8, in which the gap variation is corrected by adjusting mechanically the in-vacuum beam. What is important in this method is that the correction can be done at CT without breaking the vacuum, i.e., an 'in-situ' field correction is possible. The correction method has been tested to check the feasibility using the new CPMU with a magnetic period of 14 mm and a magnetic length of 1.7 m constructed for Swiss Light Source. In this paper, the principle and results are described together with the details of the new measurement system SAFALI (self aligned field analyzer with laser instrumentation) for the field measurement of CPMUs.
MAX-lab, Lund
The MAX IV light source, presently under construction at MAX-lab in Lund, Sweden, will consist of two separate storage rings and a linac-driven short-pulse facility. The two storage rings are operated at different energies, 3 GeV and 1.5 GeV, to provide synchrotron radiation of high brightness over a broad spectral range. The 3 GeV linac serves as a full-energy injector for the storage rings as well as the driver of the short-pulse facility delivering intense x-ray pulses. The paper describes a selection of possible insertion devices to be installed at the MAX IV 3 GeV ring and the expected heat loads produced by the insertion devices.
NCTU, Hsinchu
NSRRC, Hsinchu
A wiggler with the property of low total radiation power and keeping high photon flux in hard x-ray region, 5-20 keV, which is necessary for the special demand of users, was under investigated for reducing the difficulty of the design of optical components in the beam line and decreasing the load of RF cavity power. Such an insertion devise was called wiggler-like undulator. The spectrum of wiggler-like undulater was investigated with a code, of which the algorithm is based on the compromising between photon flux and radiation power of insertion devices for spectrum optimization. The property of the spectrum of the wiggler-like undulator are discussed herein. Furthermore, the brilliance and the power distribution are somehow also discussed.
NSRRC, Hsinchu
An elliptically polarized undulator of length 3.5 m and period length 48 mm (EPU48) is designed to fulfil experiments on spin-polarized PES and inelastic scattering at the Taiwan Photon Source (TPS). EPU48 would be used to produce variously polarized light in the soft X-ray spectral domain 0.4-1.5 keV. To achieve efficient mechanical performance and a high quality of photon source, a new manufacturing method by casting is adopted to fabricate a key component of the carriage of the undulator at National Synchrotron Radiation Research Center (NSRRC). We expect this approach to bestow advantages of decreased assembly error, increased rigidity and highly precise properties. Here we describe details of the design of the magnetic circuit and the mechanical design of the EPU48 based on this new concept of engineering construction.
BNL, Upton, Long Island, New York
National Synchrotron Light Source-II (NSLS-II) project is now in the construction stage. A new insertion device (ID) magnetic measurement facility (MMF) is being set up at Brookhaven National Laboratory in order to satisfy the stringent requirement on the magnetic field measurement of IDs. ISO-Class7 temperature stabilized clean room is being constructed for this purpose. A state-of-the-art Hall probe bench and integrated field measurement system will be installed therein. IDs in the project baseline scope include six damping wigglers, two elliptically polarizing undulators (EPUs), three 3.0m long in-vacuum undulators (IVUs) and one 1.5m long IVU. Three-pole wigglers with peak field over 1 Tesla will be utilized to accommodate the users of bending magnet radiation at the NSLS. Future plan includes: 1) an in-vacuum magnetic measurement system, 2) use of PrFeB magnet for improved cryo undulator, 3) development of advanced optimization program for sorting and shimming of IDs, 4) development of a closed loop He gas refrigerator, 5) switchable quasi-periodic EPU. Design features of the baseline devices, IDMMF and the future plans for NSLS-II ID activities are described.
Sheffield University, Sheffield
STFC/RAL, Chilton, Didcot, Oxon
The MICE experiment uses a beam of low energy muons to test the feasibility of ionisation cooling. This beam is derived parasitically from the ISIS accelerator at the Rutherford Appleton Laboratory. A target mechanism has been developed and deployed that rapidly inserts a small titanium target into the circulating proton beam immediately prior to extraction without undue disturbance of the primary ISIS beam. The first target drive was installed in ISIS during 2008 and operated successfully for over 100,000 pulses. A second upgraded design was installed in 2009 and is currently in operation. The technical specification for this upgraded design is given and the motivation for many of the improvements is discussed. In addition possible future improvements to the current design are discussed.
Cockcroft Institute, Warrington, Cheshire
STFC/DL, Daresbury, Warrington, Cheshire
The University of Liverpool, Liverpool
The longitudinal wake fields have been calculated by using 3D code, CST Particle Studio, for a number of different vacuum chamber components of the 6.4 km ILC damping ring design. Based on the results, studies of bunch lengthening and single-bunch instabilities have been carried out. Bunch lengthening from a particle tracking code are compared with results from numerical solution of the Haissinski equation. The tracking code is used to predict the threshold for single-bunch instabilities.
CERN, Geneva
The operation of the LHC imposes minimum maintenance time, when needed corrections to all systems are to be carried out. Today's maintenance management tools at CERN are seen as too slow and cumbersome for such a challenge. The short duration of the technical stops (72 h/month) requires preparation of jobs in advance, and coordination of all involved teams; at the same time, the radio-protection of personnel in the LHC underground areas imposes a strict "As Low As Reasonably Achievable"(ALARA) policy for the works' duration. In order to perform a maximum of tasks in a short time, a mobile tool for the manipulation of job and equipment data has been created. The ability to signal a new job to a team in the field will avoid unnecessary trips to the tunnel; the signaling of a job's completion (and its details) will allow subsequent jobs to start promptly and with more information; finally, the possibility to consult equipment's full manufacturing and installation data "in situ" will help with the investigation of unforeseen situations. In a 27 km environment with scarce Wi-Fi connectivity, an online light tool is now available, covering the essentials of asset maintenance tasks.
LNLS, Campinas
In this paper we report on recent developments in transverse coupling characterization and compensation in the UVX storage ring at the Brazilian Synchrotron Light Laboratory (LNLS). We have designed and manufactured a compact skew quadrupole with which it was possible to completely compensate coupling introduced by insertion devices (IDs) in the ring.
KURRI, Osaka
Until today, scaling FFAG accelerator were only designed in a ring shape. But a new criteria of the magnetic field configuration satisfying the scaling condition even for straight FFAG beam line has been recently found. Moreover, combining different types of cells can be used to imagine new lattices. Various applications using these recent developments are here examined: inprovements of the PRISM project and the ERIT project, and a zero-chromatic carbon gantry concept are presented.
Kyungpook National University, Daegu
Pohang Light Source-Ⅱ (PLS-Ⅱ) is an upgrade project of the existing 2.5 GeV PLS. The circumference, beam current and energy of PLS-Ⅱ storage ring are 281.82 m, 400 mA and 3 GeV, respectively. The upgrade project has many issues on beam dynamics. We investigated lattice optimization such as lattice corrections, dynamic aperture, selection of optimized tune & emittance and effects of insertion devices. MAD, SAD and Elegant have been used to the lattice optimization. We investigated the effects of machine errors and 20 IDs to the dynamic aperture. PLS-Ⅱ lattice include twenty insertion devices and their effects on the beam dynamics are investigated. We also investigate possibility to reduce the emittance by increasing horizontal betatron tune and adjusting the dispersion by using of MAD, SAD and Elegant and also examined the required strengths of sextupoles for the various emittances.
CERN, Geneva
The main guidelines of the LHC insertion (IR) upgrade Phase I are 1) the development of wider aperture (120 mm) and lower gradient (~120 T/m) quadrupoles using the well-characterized Nb-Ti technology in order to replace the existing inner triplets (IT) equipping the ATLAS and CMS high-luminosity IRs of the LHC, 2) while maximizing the use of the current LHC infrastructure, in particular leaving unchanged the so-called "matching sections" (MS) and "dispersion suppressors" (DS) of these two insertions. One of the initial goals was to be able to squeeze the optics up to a beta* of 25 cm. However, optics solutions with a beta* of 30 cm seems already to be at edge of achievability, both in terms of the IT and MS mechanical acceptance, gradients of the MS and DS quadrupole magnets, and correctability by the LHC arc sextupoles of the huge chromatic aberrations induced by the new inner triplet at ultimate beta*. The layout of the new inner triplet and the corresponding injection and collision optics will be presented and analyzed both in terms of aperture, squeeze-ability and chromatic correction.
CERN, Geneva
During the first years of operation of the LHC unknown field errors or misalignments could lead to unmatched optics and discrepancies with respect to the model. This could affect some critical parameters such as the luminosity or the lifetime. It is therefore desirable to implement tools which allow for fine tuning of the IP optics and could be used during the commissioning phase of the LHC. In this paper we report on the implementation the performances and the limitations of these commissioning tools.
NSRRC, Hsinchu
In this paper, the simulation techniques of insertion device (ID) were discussed. Piecewise hard-edge model was used to estimate the tune shift and changes of emittance and energy spread, while kick map model was used for particle tracking. Optical functions and tune shifts can also be derived by this model. Frequency maps as well as the beta-beating and its correction of Phase I IDs are demonstrated.
SOLEIL, Gif-sur-Yvette
SOLEIL, the French 2.75 GeV high brilliance third generation synchrotron light source is delivering photons to 20 beam lines and is presently equipped with 17 insertion devices. Significant reduction of injection efficiency and beam lifetime are observed when using some undulator configurations in daily operation. Measurements on electron beam, such as beam lifetime versus RF voltage, have shown that the energy acceptance is strongly reduced by the combined non linear effects of the four U20 in-vacuum undulators and the HU640 10m long undulator used in linear vertical polarization mode. This paper will present the on and off momentum frequency map measurements that have been performed in order to investigate such effects. The reduction of the on momentum dynamic aperture in the presence of the U20 undulators is confirmed. The off momentum frequency map measurements confirm that the energy acceptance of the bare machine is very large as predicted by tracking calculations, and clearly exhibit the strong energy acceptance reduction due to undulators.
CELLS-ALBA Synchrotron, Cerdanyola del Vallès
The synchrotron light source ALBA incorporates 6 insertion devices (2 Apple-II type undulators, 2 plannar in-vacuum undulators, 1 normal conducting multipole wiggler and 1 superconduction multipole wiggler) at the start of operation. The effect of the different IDs in the performance of the facility is evaluated, using several methods (kick maps, hard edge models, dynamic multipoles, …), including a comparison of the agreement of the different models and simulation codes. According to the results, and due mainly to the influence of the superconducting wiggler, a new working point has been selected.