CITATIONS for Laurent S. NADOLSKI generated on Sat Jan 5 11:42:58 CET 2013

The average electron beam energy for the operational mode of 400 mA in 416 bunches in the SOLEIL storage ring was measured to be 2.73724 0.00016 GeV with an accuracy of 5.9×10^-5 using the method of resonant spin depolarization (RSD). A Touschek-dominated electron beam was excited using a shaker magnet, and the beam polarization and depolarization were monitored using the change in beam lifetime and beam loss rate. To establish the primary condition that is required to perform energy measurement using the RSD method, the radiative beam polarization was first simulated using the SLIM beam dynamics code and then measured using the relative increase of beam lifetime for a Touschek-dominated electron beam. With a fast frequency sweep rate, the main depolarization resonance to be used to extract the beam energy, along with sidebands within the range of frequency sweep, was identified during our first trials. Sweeping the frequency of the excitation field around the main resonance with a slower frequency sweep rate, the beam energy measurement accuracy was increased from 1.7×10^-4 to 5.9×10^-5. Finally, the effects of closed orbit distortions on the radiative polarization and measured energy accuracy are discussed.

For a storage ring equipped with zero-gradient bending magnets, installing a Robinson wiggler (RW) [1] in a non- zero dispersion section enables emittance reduction. For SOLEIL, the horizontal emittance can be divided by up to a factor of 2 by installing a single RW. In this paper, the concept of RW is described, the expected gain for SOLEIL storage ring with the impact on the photon flux, the bright- ness, and the beam size are presented. A preliminary mag- netic design for the RW is also proposed.

The production of steady-state Coherent Synchrotron Radiation has been recently achieved in SOLEIL synchrotron using low-alpha configurations. Although the increase in THz intensity is advantageous for FTIR measurements, the signal-to-noise ratio is deteriorated by intensity fluctuations and aperiodic noise. However, we demonstrate here the possibility to use CSR as a source for FTIR spectroscopy at high resolution (10^-3 cm^-1) by using a noise correction system based on double detection. Combined to the high stability optics of the infrared beamline AILES, it allows to extend the range of optimal use of the synchrotron source down to ˜0.2 THz (7 cm^-1).

SOLEIL global orbit feedback systems (slow and fast), based on 122 electron Beam Position Monitor (e-BPM) readings, are in operation since 2008 and give very satisfying performances (0.1Hz-500Hz vertical noise below 300 nm RMS and long term (8h) drifts below 1μm RMS). Whereas each straight section is equipped with an upstream and downstream e-BPM, there is no e-BPM next to a dipole magnet. For that reason, photon BPMs (x- BPMs) in the dipole beamline frontends give additional information that can be used to better stabilize the source point in the dipoles. In fact x-BPMs provide also a better position angular measurement resolution, as they are located at 4 meters from the source point. Results presented in this paper show that vertical position stability on bending magnet beamlines can be improved by including their x-BPM measurements in the global orbit feedback systems. As a first step x-BPMs have been introduced in the Slow Orbit FeedBack system (SOFB) that corrects the orbit with a repetition rate of 0.1Hz. In a second step x-BPMs will be introduced in the Fast Orbit FeedBack system (FOFB) running at a repetition rate of 10 kHz.

With the aim of lowering further the horizontal emittance of the SOLEIL ring, a study is made on the magnet lattice and linear optics by introducing superbends that associate longitudinal dipole field variations, under the constraint of leaving the circumference of the ring as well as the existing straight sections unchanged. A solution giving a sub-nanometer emittance and achieving more than a factor of 5 of reduction on the effective emittance is found with a QBA (Quadrupole Bend Achromat) lattice.

Low momentum compaction factor (low-alpha) operation has been recently added as a new operation mode at synchrotron SOLEIL. Both time resolved X-ray and THz radiation user communities are taking benefit from a hybrid filling pattern with a 4.8 ps RMS bunch length. With an alpha value of 1.7 10^-5 (nominal alpha /25) and a bunch current of 65 , stable THz radiation is produced in the range of 8 - 20 cm^-1. The optics presented at IPAC'11 [1] has been selected for the operation. This paper gives the comprehensive experimental characterization of this optics. Specificities of the low-alpha operation, driven by the very demanding user experiments, are reviewed: beam position stability, extremely tight injected current increments during Top-up injection, and radiation safety aspects due to beam losses at injection.

SOLEIL, the French 2.75 GeV synchrotron light source is delivering photons to 24 beamlines and is presently equipped with 24 insertion devices (ID) including a high field and small gap in-vacuum wiggler [1]. This paper presents the continuous work performed to reduce the strong non-linear effects of several IDs. On one side, the ID defaults have been accurately identified using on-beam measurements, and magnetic correction developments are going on and on the other side, a new optics has been optimised in terms of beta-functions (at the ID location) and non-linear dynamics in order to improve the injection efficiency and the beam lifetime in the presence of IDs. In parallel, an extensive experimental optimization has been performed to prepare the operation with an additional quadrupole triplet that provides double low vertical beta functions in one long straight section that will accommodate two canted in-vacuum undulators [2]. The paper presents also the dedicated "low-α" optics that has been optimised for short bunch production.

The electron beam orbit stability has been significantly improved at synchrotron SOLEIL. Low frequency noise sources have been located and identified: the fans installed on the storage ring to cool down the ceramic chambers of the kickers, shaker and FCT, were slightly wobbling the electron beam orbit at 46, 50, 54, and 108 Hz. The location method and the solutions that allow reducing the noise from 0.8 μm RMS down to 0.3 μm are presented. Besides, a new 160 m long beamline, NANOSCOPIUM, is being installed on a canted straight section. Its photon beam position stability requirements are very tight calling for the following improvements: addition of 2 more BPMs and fast correctors in the orbit feedback loops, new INVAR stands for BPM and XBPM integrating Hydrostatic Level System sensors. This paper is also discussing other projects that did or will contribute to the improvement of beam orbit stability: installation of 175 temperature sensors on the storage ring, a new analog feedforward correction system for insertion devices, and the use of the bending magnet X-BPM vertical beam positions in the slow and fast orbit feedback loops.

The booster power supplies influence the storage ring beam position in synchrotron SOLEIL.To compensate these disturbances, a dedicated wire loop fed by an in- house developed power supply (PS) was installed in the booster cable tray. The power supply output current is driven by direct measurement of the 3Hz booster power supplies. This paper discusses the PS requirements according to beam position measurements and the original design. Finally the orbit stability improvements when this power supply is switched on are presented.

Today, the vast majority of electron storage rings delivering synchrotron radiation for general user operation offer a dedicated infrared port. There is growing interest expressed by various scientific communities to exploit the mid- IR emission in microspectroscopy, as well as the far infrared (also called THz) range for spectroscopy. Compared with a thermal (laboratory-based source), IR synchrotron radiation sources offer enhanced brilliance of about two to three orders of magnitude in the mid-IR energy range, and enhanced flux and brilliance in the far-IR energy range. Synchrotron radiation also has a unique combination of a broad wavelength band together with a well defined time structure. Thermal sources (globar, mercury filament) have excellent stability. Because the sampling rate of a typical IR Fourier-transform spectroscopy experiment is in the kHz range (depending on the bandwidth of the detector), instabilities of various origins present in synchrotron radiation sources play a crucial role. Noise recordings at two different IR ports located at the Swiss Light Source and SOLEIL (France), under conditions relevant to real experiments, are discussed. The lowest electron beam fluctuations detectable in IR spectra have been quantified and are shown to be much smaller than what is routinely recorded by beam-position monitors.

SOLEIL delivers photons to 25 Beamlines. Up to 24 very diverse Insertion Devices (ID) are now installed on the Storage Ring. The most recent one is a cryogenic in- vacuum undulator designed and built at SOLEIL. Work is continuing on beam dynamics and magnetic corrections to reduce the nonlinear effects of all these IDs. A new optics incorporating an additional quadrupole triplet in one long straight section has been successfully tested and will be put in operation by fall 2011. A new coupling correction will also be implemented in order to maintain the ratio between the vertical and the horizontal emittances at a fixed 1% for any IDs configuration. The electron beam orbit stability has been significantly improved reaching a residual noise of 200 nm RMS on all hard X-ray ID Beamlines. Photon LIBERA modules equip X-BPM located on the bending magnet Beamlines; they will be integrated soon in the orbit feedback loops. 4905 hours have been delivered in 2010 to the Beamlines with an availability of 96.3%. After seven months in 2011, the availability is of 98.3%.

SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is a third generation synchrotron light source under construction near Amman (Jordan), which is expected to begin operation in 2015. SESAME will foster scientific and technological excellence in the Middle East and the Mediterranean region, build scientific bridges between neighbouring countries and foster mutual understanding through international cooperation. The members of SESAME are currently Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, the Palestinian Authority and Turkey. An overview about the progress of the facility and the general plan will be given in this talk. Then I will focus on the control system by explaining how this part is managed: the technical choice, the main deadlines, the local staff, the international virtual control team, and the first results.

This paper presents the different approaches and tools that have been recently developed, while trying to under- stand or predict the non-linear dynamics of electron storage rings. Different algorithms have been lately used at differ- ent places to optimize the sextupole tunings, while the re- finement of the models of existing machines together with more accurate measurement techniques enable us now to have a much better understanding of the limitations of such facilities especially in the presence of insertion devices.

At SOLEIL, the time resolved community benefits from a single bunch operation few weeks a year. Meanwhile most of the multi-bunch filling pattern based experiments are not possible due to the low photon flux. Following the pioneer work performed at ALS [1], a new operation mode is under study at SOLEIL where the storage ring is filled up with a special hybrid mode: 3/4 multi-bunch filling pattern and a single bunch with higher current in the last 1/4. The so-called pseudo single bunch- filling pattern is obtained if the closed orbit of the single bunch is not the same as the one of the other bunches. Preliminary results are presented where the existing fast kicker magnet time impulse response has been significantly reduced while its frequency was increased from 3 Hz up to 1 kHz. This magnet is used as an additional corrector magnet to change only the single bunch closed orbit. First experimental results observed at one interested beam-line are also discussed.

Time resolved experiments are one of the major services that synchrotrons can provide to scientists. The short, high frequency and regular flashes of synchrotron light are a fantastic tool to study the evolution of phenomena over time. To carry out time resolved experiments, beamlines need to synchronize their devices with these flashes of light with a jitter shorter than the pulse duration. For that purpose, Synchrotron SOLEIL has developed the TimBeL board fully interfaced to TANGO framework. This paper presents the main features required by time resolved experiments and how we achieved our goals with the TimBeL board.

The electron beam energy on SOLEIL storage ring wassuccessfully measured using spin depolarization method after several attempts over the pastfew years. The experimental results demonstrate that the effective polarization was 91.3% 3% and polarization time was172.3 minutes as expected from the simulation using SLIM code. The beam was depolarized using an AC shaker and the depolarization was monitored using DCCT and beam loss monitors. The beam energy was measured with accuracy up to a few 10-5.

SOLEIL, the French 2.75GeV 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 specific 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 by the 10m long HU640 electromagnetic undulator when it is used in linear vertical (LV) polarization mode. This paper will present off-momentum frequency map measurements that have been performed in order to investigate such effects. These 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.

We present experimental and numerical results on Terahertz coherent synchrotron radiation obtained in the beamline AILES at the synchrotron SOLEIL. Depending on the storage ring configuration and on the electron bunch current we observed either stable or instable signals.

SOLEIL the French synchrotron light source is now routinely delivering photons to 21 beamlines with a current of 400 mA in top-up mode. The beam position stability is within the one micron range thanks to an original combination of the slow and fast orbit feedback systems, as well as the improved tunnel temperature regulation. The bunch by bunch transverse feedback is running with two independent horizontal and vertical loops. For canted undulator implementations, a three- magnet chicane has been installed in a medium straight whereas an additional triplet of quadrupoles was inserted in the middle of a long straight in order to create a double low vertical beta. 18 insertion devices are presently installed in the storage ring, four will be added in 2010 while another five, including a cryogenic undulator, are under construction,. Following the significant progression of the vacuum conditioning, the lifetime is now mainly Touschek limited. An electron bunch slicing setup is also being installed in order to provide 100 fs long X-ray pulses to two existing beamlines.  4500 hours of beam have been delivered in 2009 to the beamlines with an availability above 96 % thanks, among others, to the very reliable operation of the unique SOLEIL RF system.

SOLEIL is the French 2.75 GeV high brilliance third generation synchrotron light source delivering photons to 20 beamlines with a current of 400 mA in multibunch or hybrid modes, and 60 mA in 8 bunch mode. Already 17 insertion devices are installed and 9 others are planned in the next two coming years. Among them, two canted in- vacuum insertion devices, for the Nanoscopium and Tomography beamlines, will be accommodated in a 12 m long straight section, with a 6.5 mrad separation angle. These  150 and  200 m long beamlines will exploit the high brilliance and coherence characteristics of the X-ray (5-25 keV) beam, both for diffraction limited focusing and for phase contrast imaging. To provide low vertical beta functions at each undulator, an extra triplet of quadrupoles was added in the middle of the section. We present here the lattice implementation footprint, the different working points under investigations as well as the first results of the measurements on the machine performance.

This introductory course gives an overview of why diagnostics equipment is crucial for running accelerator facilities. Even if significant progress has been made over the last two decades in terms of designing and modelling an accel- erator, model and reality differ all the time. The commissioning stages of a synchrotron light source and the stability of the beam positions are taken as examples. The main orbit disturbances are driven by alignment errors, drifts with temperature, vibrations, timing system jitters. Reaching a high level of stability and beam availability in facilities is very challenging. This is attained by driving forward the equipment performance. This starts off with the design of the building and the girders supporting the equipment, the optimization of magnets, the stability and precisionof the power supply, the diagnostics elec- tronics, and the careful design of the beamlines. In addition, passive and active corrections have to be devised to maintain the highly demanding beam quali- ties on a daily basis.

Beam orbit stability is a crucial parameter for 3rd generation light sources in order to achieve their optimum performance. Sub-micron stability is now a common requirement for vertical beam position. To reach such performance, Global Orbit Feedback Systems are mandatory. This paper describes the different design approaches for Global Orbit Feedback Systems. A few machines can use a single set of strong correctors. Most of them have their strong corrector bandwidth limited by eddy currents in aluminum vacuum chamber, or power- supply speed together with the required digitization granularity. Then, a second set of fast correctors is required for high frequency correction. But Fast and Slow Orbit Feedback Systems cannot work together with a common frequency range, they fight each other. An earlier solution has been to separate fast and slow systems by a frequency dead-band. This approach does not allow correcting efficiently the orbit shifts due to the gap movements of the increasingly sophisticated insertion devices that are installed on new machines. The different solutions that have been recently implemented are reviewed.

SOLEIL storage ring presents a very high fraction of the total circumference dedicated to accommodate insertion devices. Over the planned 25 insertion devices (ID) presenting a large variety of systems, 17 have been already installed and commissioned in May 2009 (14 are now in place). The present status of the SOLEIL ID is given in particular with their achieved performances.

SOLEIL is the French 2.75 GeV high brilliance third generation synchrotron light source delivering photons to beam-lines since January 2007. Reaching micrometer to sub-micrometer level stability for the photon beams is re- quired but very challenging. Since September 2008, a fast orbit feedback has been running for daily operation. The performance of the system will be presented with respect to those achieved with the slow orbit feedback system. Sta- tus of the interaction of both feedback systems will be dis- cussed. Moreover new X-BPMs have been installed on the front-ends of dipole and undulator based beam-lines. A to- tal number of 9 vibration sensors are now installed in the storage ring tunnel, on the experimental slab, and outside the building in order to help locating the different noise sources. Detailed results will be presented and debated.

Thanks to beam-based measurements, the theoretical model of the storage ring lattice has been improved. First, the quadrupole lengths in the hard edge model were finely tuned to get good agreement with the experimental measurements of betatron tunes for significantly different optics. Second, a machine model including the coupling errors has been built using the crosstalk closed orbit acquisitions. As a validation, the coupling effect of the 10m long HU640 undulator has been evaluated through this coupling model. Finally, the non-linear model was modified to better fit with beam-based on-momentum frequency map measurements. In addition to the thick sextupole model, the non-linear effect induced by the fringe field in the quadrupole magnets has been introduced. Simulated and measured on-momentum tune shifts with transverse amplitudes and dynamic aperture are then compared.

The successful correction of non-linear resonances in DIAMOND [1] using the BPM turn-by-turn data has mo- tivated testing this approach in SOLEIL in collaboration with CERN. We report on the first experiences towards the correction of non-linear resonances in SOLEIL.

SOLEIL is the French 2.75 GeV third generation synchrotron radiation light source. Eleven undulators are installed yet in the storage ring and nineteen more Insertion Devices (ID) will be installed in the ring by January 2010. Among the installed IDs, there are four electromagnetic undulators of two different designs: one 640 mm period air coil undulator called HU640 [1] and three 256 mm period undulators called HU256 [2], made up of independent H yoke dipoles. The HU640 provides photons in any polarisation from linear to elliptical, in a range extending from 5 to 40 eV, thanks to three different groups of coils powered independently. The HU256, which are subject to hysteresis, provide horizontal and vertical, periodic or quasi-periodic linear polarisations, and also circular polarisation, covering a energy range from 10 eV to 1 keV. The effects of each undulator on the closed orbit have been extensive studied, and compensated, using dedicated embedded steering coils. The correction method is explained and its results are shown. Finally, the first measurements of the radiation produced will be shown and compared to previsions.

SOLEIL, the French 2.75 GeV third generation light source, is delivering photons to beam lines in routine operation since January 2007. The storage ring is presently equipped with 14 insertion devices. Commissioning the insertion devices consists in characterizing all the effects on beam dynamics in terms of closed orbit distortion, focusing, chromaticity, coupling, injection efficiency, beam lifetime and sensitivity to working point. We will focus here on the significant effects observed with some undulators.

The paper presents the results of electron beam closed orbit distortion (COD) and tune shift measurements performed on three different APPLE-II type undulators using horizontal local closed orbit bumps. In agreement with data from other storage rings, our results show that, when APPLE-II undulators are used in elliptical, linear- vertical or linear-tilted polarization modes, the measured tune shifts and COD can not be explained only by residual first-order focusing effects: taking into account the second-order, or dynamic focusing effects, is necessary. We describe a COD interpretation method allowing for straightforward comparison of the measured effects on electron beam with predictions from calculations and magnetic measurements. The observed dynamic effects are in good agreement with calculations performed using RADIA magnetostatics code.

SOLEIL is the French 2.75 GeV third generation synchrotron light source delivering beam to Users since January 2007. As of June 2008 up to 14 beam-lines are taking beam, 7 from insertion devices (IDs), 2 from IR ports, and 5 from dipole ports. Users have full control of their IDs. With 300 mA maximum stored beam current in multi-bunch filling pattern, and position stabilities in the few micron range, the main target performances have been reached. A beam of 50 mA in 8 bunches was delivered to Users for the first time in December 2007 for time structure experiments. Operation and performance status are given, namely subsystem behaviour (RF, vacuum,...), beam optics, orbit stability, beam lifetime, and operation statistics. Then the main objectives for 2008 will be reviewed: delivery of 4000 hours of beam to the beamlines, installation and commissioning of a second cryomodule for reaching the 500 mA current target, construction and installation of 3 new IDs, improvement of the orbit stability with a fast orbit feedback complementary to the slow orbit one, and preparation for top-up operation.

The SOLEIL Fast Orbit Feedback system has been integrated in the BPM electronics, using the FPGA resources of the LIBERA modules. On top of their position measurement, the FPGAs compute the orbit correction and drive the power-supplies of the 48 dedicated air coil correctors. Position data are distributed all over the ring by a dedicated network connecting the 120 BPMs modules together. The correction rate is 10 kHz and is applied with low latency. Even if at almost all the source points, the high frequency stability specifications have already been achieved thanks to great care in the design of the machine, remaining vibrations are still observed in the 46-54 Hz band and during the changes in gap and phase of some insertion devices. Those perturbations can be efficiently damped by the Fast Orbit Feedback system. While the BPM system has been operational for some time, the Fast Orbit Feedback system is presently in its commissioning phase. The design and first results of the latter are reported.

SOLEIL is a 2.75 GeV third generation synchrotron light source delivering photons to beam-lines since January 2007. With a 3.7 nm.rad horizontal emittance, its optics is based on a strong focusing lattice. Large on- and off- momentum apertures are required in order to provide good injection efficiency and as large as possible Touschek beam lifetime. It is then fundamental to be able to understand the limitations of these key figures. In order to probe the trans- verse non linear dynamics two pinger magnets have been installed into the injection straight section during the sum- mer 2007. In this paper, their calibration will be described. Then first comparisons between modeled and real machine will be given for betatron tune-shifts with amplitudes and frequency maps. To end the non-linear impact of insertion devices on beam dynamics will be discussed.

SOLEIL is a 2.75 GeV third generation synchrotron light source delivering photons to beam-lines since January 2007. Stability of the beam-line source points is crucial for the user experiments. Typically this stability has to be below one tenth of the transverse beam sizes. This is challenging especially in the vertical plane leading to sub- micrometer values. This paper will describe the position stability achieved today without and with the slow orbit feedback. Impact of different noise sources and present limitations will be described. To end an improvement strat- egy will be given for short and medium terms.

SOLEIL is a 354 m long third generation light source located South of Paris (France). In this paper, the first attempts using LOCO is described together with prob- lems encountered due to the storage ring lattice compact- ness. The introduction into the code of constraints on the quadrupole gradient variations gives tremendous improve- ments. The convergence is satisfactory, beta-beatings are reduced from 5 to 0.3% RMS in both planes. Restoring the symmetry of the lattice enhanced the performance of the storage ring. In the last part, different ways of using LOCO as a powerful diagnostics tool are given.

The first results of commissioning for the French Synchrotron Radiation Facility SOLEIL at 2.75 GeV are presented. Perspectives for the fourth generation light source based on the ARC-EN-CIEL project are described.

SOLEIL is a third generation Synchrotron radiation Source, under construction in France at St Aubin, near Paris. The Storage Ring consists in a 357 m circumference ring, with 16 cells and 24 straight sections (4×12m, 12×7m, 8×3.6m), out of which up to 21 will house insertion devices. The optics, with distributed dispersion, features a low 3.7 nm.rad emittance at the 2.75 GeV operating energy, so as to provide high brilliance, from the VUV up to the hard X ray domain. In order to provide a long lifetime, and beam position stabilities in the micron range, significant attention was paid at each design stage (optics, magnets, beam position monitors, vacuum and RF systems,..), including the design of the building and infrastructure, the construction of which is now complete. This resulted in some unprecedented approaches such as the intensive use of NEG coating Aluminium vessels, or the development of a dedicated superconducting RF cavity and of 190 kW solid state RF amplifiers. The construction, started in 2002, is now completed. The injector system (100 MeV Linac) and the 3 Hz full energy Booster synchrotron have reached nominal operating conditions by fall 2005. The installation of the Storage Ring was just completed and its commissioning started in May 2006. First 9 turns in the ring were achieved on May the 14th, and visible synchrotron radiation was also observed on a CCD camera. Innovative insertion devices were designed and built so as to provide the best possible performances in an energy range as large as 5 eV to 20 keV. These are helical electromagnetic devices with 640 mm and 256 mm periods, APPLE II type undulators with 80 mm period, and in-vacuum hybrid undulators with 20 mm period. Two infra-red beamlines providing both edge and constant dipole field emission are also under construction and a superconducting wiggler is currently being designed in order to provide high flux in the 10 to 50 keV range. A first set of 10 beamlines (out of 24 included in the project) is being built and will be tested from summer 2006 onwards, with the aim of starting Users operation by the beginning of 2007.

SOLEIL is a third generation light source built in France, near Paris. Its BPM system is important for machine physics studies and for delivering stable beams to the users. A beam stable to 1/10th of the dimensions requires submicron stability in the vertical plane. The monitors anchored either to the girders or to the ground, are fixed points of the vacuum chamber. The electronics design was driven by combined efforts through active communication between accelerator laboratories (SOLEIL at first, later joined by DIAMOND) and Instrumentation Technologies. The result is the “Libera Electron” beam position processor. This paper reports on the performance of this new electronics installed on SOLEIL Storage Ring. It combines a 0.2 μm rms resolution and micron level stability for beam delivery with accurate turn-by-turn measurements (3 μm resolution at 0.8 MHz) for machine commissioning and beam physics studies. It also features position interlock, tune measurement, and post-mortem capabilities. A Slow Orbit Feedback for correcting low frequency drifts (0 to 0.1Hz) is currently in operation. The Fast Orbit Feedback to be implemented soon will suppress higher frequency perturbations up to 100Hz.

The French 3rd generation synchrotron light source, SOLEIL, was successfully commissioned in 2006. The Linac and the Booster are operational at their performance design. During the early phase of storage ring commissioning, essential designed parameters were reached very quickly even though the project incorporates some innovative techniques such as the use of a superconducting RF cavity, solid state RF amplifiers, NEG coating for all straight parts of the storage ring and new BPM electronics. Prior to the start of the commissioning, most of Insertion Device low gap vacuum vessels, including 10 mm inner vertical aperture vessels, were installed on the ring. The main results of one year commissioning and achieved performances are summarized in this paper.

SOLEIL, the 2.75 GeV new French Synchrotron Radiation Facility, located near Paris, is under commissioning. Here are reported the main results obtained especially on the storage ring. The beam dynamics characterisation of the 3.7 nm.rad optics is presented, as well as the first measurements of the instability thresholds. Furthermore comparison is made with expectations of the linear optics model and instability calculations. First experience with innovative devices and technologies is also presented: TANGO control system, BPM system, extensive use of NEG coated vacuum vessels, unconventional RF system (Solid state amplifiers and superconducting cavities). Seven insertion devices accommodating a wide energy range from 5 eV to 30 keV (in-vacuum, Apple II, large period electromagnetic types) are now installed on the machine and some of them are producing the first photon beams which are delivered to the beamlines. Finally a roadmap towards beam delivery to users will be presented.

SOLEIL is a third generation Synchrotron radiation Source, under construction in France near Paris. The Storage Ring consists in a 354 m circumference ring, with 16 cells and 24 straight sections, out of which up to 21 will house Insertion Devices (ID). The optics features a low 3.7 nm.rad emittance at the 2.75 GeV operating energy, so as to provide high brilliance, from the VUV up to the hard X ray domain. In order to reach a long beam lifetime, and beam position stabilities in the micron range, significant attention was paid at each design stage (optics, magnets, beam position monitors, vacuum and RF systems,..), including on the design of the building, the construction of which is now complete. This resulted in some unprecedented approaches such as the intensive use of NEG coating vessels, or the development of a dedicated SC RF cavity and of 200 kW solid state RF amplifiers. The injector system (100 MeV Linac) and the 3 Hz full energy Booster synchrotron have reached nominal operating conditions by fall 2005, while the ring commissioning started in May 2006. Innovative ID's were designed and built so as to provide the best possible performances in a wide energy range (5 eV to 50 keV).

The SOLEIL light source is a 2.75 GeV third generation synchrotron radiation facility under construction near Paris. Storage ring commissioning began in May 2006 and 10 beamlines will start operation for the end of 2006. This paper will describe, from the electronics and software point of view, the technical choices and architectures of the control systems of accelerators and beamlines, and will give the current status of the deployment.

First beam-based alignment (BBA) measurements have been carried out during the commissioning of the SOLEIL Storage Ring that started in May 2006. The results will allow calibrating the zero reading of the 120 Beam Posi- tion Monitors (BPMs) with respect to the magnetic cen- tre of the adjacent quadrupoles or sextupoles. We plan to use two different BBA methods related to each multi- polar magnet BPMs being either adjacent to quadrupoles or sextupoles. Moreover, multiple different experiments will favour results cross-checking. As we did not have enough time to validate our algorithms, we present here only the automated methods we plan to apply and the MATLAB user interface dedicated to BBA.

The commissioning of the SOLEIL storage ring started in May 2006. The objective was to reach, within a first phase of two months, stable beam conditions at 100 mA in the multi-bunch mode that can be used for the commissioning of the beamlines. This is a challenging objective especially because SOLEIL's ring is incorporating some innovative techniques such as the use of a superconducting RF cavity, NEG coating for all straight parts of the machine and new BPM electronics. Prior to starting the commissioning, 4 Insertion Devices and most of the IDs low gap vacuum vessels, including 10 mm inner vertical aperture vessels for the Apple-II type, were installed on the ring. We report here the main results of the first commissioning experiments.

Synchrotron SOLEIL, the French third generation light source being commissioned in 2006, is the first facility us- ing TANGO as a full control system. Control applications for operation and Beam Physics Dynamics have being de- veloped using two major tools: the Matlab Middle Layer adapted from ALS and SPEAR3, and GlobalSCREEN, a commercial SCADA software. Both tools are fully inter- faced with the TANGO control system. In this paper, a sketch of the software architecture is shown. Then storage ring applications developed in house are presented. Finally configuration and database related applications (archiving, snapshot) are briefly described.

The Advanced Light Source (ALS) is a third generation synchrotron light source at Lawrence Berkeley National Laboratory (LBNL). There was an increasing demand for additional high brightness hard X-ray beamlines in the 7-40 keV range, so in August 2001, three 1.3 T normal conducting bending magnets were removed from the storage ring and replaced with 5 T superconducting magnets (Superbends). The radiation produced by these Superbends is an order of magnitude higher in photon brightness and flux at 12 keV, making them excellent sources of hard X-rays for protein crystallography and other hard X-ray applications. The Superbends did not compromise the performance of the facility in the VUV and soft X-ray regions of the spectrum. The Superbends will eventually feed 12 new beam lines, greatly enhancing the facility's capability and capacity in the hard X-ray region. The Superbend project is the biggest upgrade since the ALS storage ring was commissioned in 1993. In this paper we present an overview of the Superbend project, its challenges and the resulting impact on the ALS.

SOLEIL is a third generation light source under construction. Great care is taken at all levels of the machine design in order to reach beam stability at the micrometer level. In particular, a fast global closed-orbit feedback is foreseen for suppressing remaining beam vibrations up to 100 Hz. The correction uses the computing resource of 120 BPM electronic modules, distributed around the storage ring. Each BPM module includes a powerful FPGA that in addition to its specific BPM task leaves enough room to embed a part of the fast feedback correction algorithm. All the BPM data (including XBPMs in the future) have to be broadcasted to the 120 modules in order to compute the correction. Broadcasting the data is expected to be fast (around 20 us), thanks to eight multigigabit transceivers per module, and fast links between them. The architecture of the dedicated network is flexible enough to keep the feedback system functional even with a few disabled BPMs. The correction is applied to 46 dedicated air-core correctors in each plane at a rate of 8 kHz. Simulations will be performed in order to optimize the system in the bandwidth of interest to the machine users.

SOLEIL is a 2.75 GeV third generation synchrotron radiation facility under construction near Paris. The construction is going towards its completion. The commissionings of the LINAC and of the first transfer line are starting, the booster is already installed in the tunnel and the tests of the equipments are under way, the installation of the storage ring is just beginning. This paper presents the status of the main storage ring equipments : magnets, power supplies, vacuum system, diagnostics, RF system, front ends and insertion devices.

The SOLEIL control system, namely TANGO, devel- oped in collaboration with ESRF, is now mature and sta- ble. TANGO has been also chosen now by several other laboratories. High-level control applications implemented in the control-room for the storage ring, the two trans- fer lines, and the booster will be described in this paper. Three kinds of tools for commissioning are used. First the generic TANGO tools (alarms, simple graphical control ap- plications), which allow us to control in a simple way any TANGO Device Server. Secondly a Matlab Middle Layer (adapted from ALS and SPEAR3): Matlab is fully inter- connected with TANGO; it is used primarily for writing physics control applications. Finally GlobalSCREEN, a commercial SCADA software devoted for building oper- ation applications has been selected (panels for controlling or displaying setpoint, readback values, status of equip- ments). In addition an overview of the historical and short- term databases developed in house will be given.

The momentum aperture of a storage ring is a very im- portant parameter that strongly influences the performance, especially the beam lifetime. For the special case of syn- chrotron light sources with small emittance like the Ad- vanced Light Source (ALS), the momentum aperture de- pends strongly on the transverse dynamics. It is very sensi- tive to machine conditions such as the tunes, chromatic- ities, lattice symmetry, and spurious coupling, since de- pending on those conditions the Touschek scattered parti- cles explore different resonance regions in the phase space. In light sources, the momentum aperture usually also de- pends strongly on the vertical physical aperture. Applying frequency analysis techniques in simulations and for turn- by-turn orbit measurement data provides a very powerful tool to measure and understand limitations of the dynamic momentum aperture. The techniques presented are applica- ble to other light sources, as well as damping rings and many types of colliders.

L'Analyse en Fréquence est une méthode numérique utilisant une analyse de Fourier raffinée qui permet de donner une représentation globale de la dynamique de systèmes multidimensionnels. Développée par J. Laskar pour étudier la dynamique planétaire, cette méthode s'est rapidement révélée comme un outil privilégié en physique des accélérateurs. Dix ans après son introduction en dynamique faisceau, l'analyse en fréquence est aujourd'hui utilisée aussi bien lors de l'optimisation de la maille d'une machine qu'expérimentalement en salle de contrôle. Lors de ce séminaire, je présenterai l'utilisation de l'analyse en fréquence pour comprendre et améliorer la dynamique transverse on et off-momentum des machines de rayonnement synchrotron de troisième génération comme SOLEIL. Je donnerai également une vue générale de son utilisation à travers le monde des accélérateurs suite au workshop Frequency Map Analysis qui s'est tenu au début avril à Orsay.

The successful commissioning of the new SPEAR3 light source at the Stanford Synchrotron Radiation Laboratory (SSRL) will be reviewed. Orbit control, beam-based alignment, and an orbit interlock were commissioned. Orbit motion was characterized as a function of frequency. The linear optics was corrected for ID focusing and coupling errors. The nonlinear optics were investigated with dynamic aperture measurements as a function of energy and tune. Preliminary measurements were made of impedances and instabilities.

The impact of several non-linear effects on energy acceptance and beam lifetime has been investigated, using the BETA and TRACY II tracking codes. The effect of all magnets multipolar components has been checked on the working point (18.20; 10.30), especially the decapolar component induced by the H- corrector. The dipolar field, which is created by additional coils in the sextupoles, generates a significant decapolar component which, together with the large distributed dispersion, can reduce significantly the dynamic acceptance at large energy deviations. This effect depends on the natural closed orbit to be corrected: corrector strengths and cross talk between the different decapolar components. The sensitivity to the number of correctors has also been evaluated. The effect of insertion devices has also been studied, integrating field maps generated by the RADIA code into the tracking codes. With undulators, such as an in-vacuum U20 and an Apple II type HU80 (with different polarization modes), it was shown that the transverse field in-homogeneity and the focusing effects generating beta-beat can affect severely the energy acceptance and the beam lifetime because of resonance excitation.

The goal of the slicing project at SOLEIL is to provide 100fs long pulses of soft and hard X-rays with reasonable flux and with a 1-10kHz repetition rate. The slicing principle is based on Zholents and Zoloterev method [1]. The SOLEIL horizontal natural optics enables the sliced pulse to be used on several consecutive straight sections without any modification to the magnet lattice. Feasibility and expected performances on two different beamlines are reported in this paper.

The successful commissioning of the new SPEAR3 light source at the Stanford Synchrotron Radiation Laboratory (SSRL) will be reviewed. Orbit control, beam-based alignment, and an orbit interlock were commissioned. Orbit motion was characterized as a function of frequency. The linear optics was corrected for ID focusing and coupling errors. The nonlinear optics were investigated with dynamic aperture measurements as a function of energy and tune. Preliminary measurements were made of impedances and instabilities.

L'architecture du système de contrôle commande du Synchrotron SOLEIL repose sur le monde TANGO (issu de l'ESRF). TANGO est un système évolutif, orienté objet, permettant de mettre en œuvre des systèmes répartis et hétérogènes. Je présenterai TANGO en me plaçant de point de vue des exigences d'une machine de rayonnement synchrotron de troisième génération. Une brève comparaison avec EPICS sera donnée. J'exposerai succinctement les outils et applications haut niveau qui seront développées pour l'opération de l'accélérateur et pour le groupe physique machine. Certaines de ces applications devront être prêtes dès avril 2004 pour le commissioning du LINAC et de LT1.

In third generation light sources like SOLEIL, the inevitable strong sextupoles lead to significant non- linearities affecting the transverse beam dynamics. We already emphasized the large contribution of transverse and longitudinal non-linearities to the SOLEIL energy acceptance: energy dependence of Twiss parameters, non- linear off-momentum closed orbit and non-linear synchrotron motion. In order to face other effects as non- linear betatron motion, synchrotron oscillation, coupling, and diffusion processes, a refined tracking was performed using a 6D tracking code. This work confirms the strong effect of the non-linear synchrotron motion and suggests to choose the working point so as to avoid any crossing of the linear coupling resonance for off-momentum particles. The use of the Frequency Map Analysis (FMA) helps to understand the different kinds of particle losses.

The construction phase of SOLEIL, the French third generation Synchrotron radiation Source has begun in January 2002 with the aim of starting Users operation in spring 2006. The machine now consists in a 354 m circumference ring, with 16 DB cells and 24 straight sections. The optics, with distributed dispersion, features a low 3.7 nmrad emittance at the 2.75 GeV operating energy, so as to provide high brilliance, from the VUV up to the hard X ray domain. In order to provide a long lifetime (18 hours), and beam position stabilities in the micron range, significant attention was paid at each design stage (optics, magnets, beam position monitors, vacuum and RF systems,..), including on the design of the building, the construction of which will start in summer 2003. All the magnets have been designed and are in the last stage to be ordered. The qualification of the 352 MHz super-conducting RF cavity prototype has been done on the ESRF ring. Insertion devices are being designed with the goal of serving a very large scientific community with high performances in an energy range as large as 5 eV to 18 keV with undulators. The contract was placed for the 100 MeV Linac for a delivery summer 2004.

Frequency map analysis [J. Laskar, Icarus 88, 266 (1990)] is used here to analyze the transverse dynamics of four third generation synchrotron light sources: the ALS, the ESRF, the SOLEIL project, and Super-ACO. Time variations of the betatron tunes give additional information for the global dynamics of the beam. The main resonances are revealed; a one-to-one correspondence between the configuration space and the frequency space can be performed. We stress that the frequency maps, and therefore the dynamics optimization, are highly sensitive to sextupolar strengths and vary in a large amount from one machine to another. The frequency maps can thus be used to characterize the different machines. "

The goal of the Femtoslicing project at the ALS is to provide 100-200 fs long pulses of soft and hard x-rays with moderate flux and with a repetion rate of 10-40 kHz for experiments concerning ultrafast dynamics in solid state physics, chemistry and biology. The femtoslicing principle employs a femtosecond laser beam to interact resonantly (inverse FEL interaction) with the electron beam in the ALS. The induced energy spread over the femtosecond du- ration is converted to a transverse displacement by exploit- ing the dispersion of the storage ring. The displaced fem- tosecond electron pulse then radiates and produces fem- tosecond synchrotron radiation. To achieve the necessary spatial separation of the energy modulated slice from the rest of the bunch, a sizeable local vertical dispersion bump in the undulator used as radiator is required. This presents challenges in terms of the nonlinear dynamics and control of the vertical emittance.

Experimental turn by turn beam position measurements were performed in order to investigate the non-linear beam dynamics in Super-ACO. The aim of these experiments is to get a better understanding of the aperture limiting effects of non-linearities and to check the model used in tracking studies. The amplitude- dependent tune shift measurements allow to highlight a strong octupolar-like component due to quadrupoles fringe field missing in the model. In addition to this point, an analysis which enables to make the distinction between a physical and a dynamic aperture limitation is also described.

The dynamics of particle accelerator beams is commonly described by a Hamiltonian of the form H = A + εB where A and B are integrable. Using Lie formalism, we give an overview of a new class of symplectic integrator [1] par- ticularly well adapted when εB is viewed as a perturbation of A. These integrators with positive step size can be con- structed with a remainder of arbitrary order n in A and or- der 2 in εB. Moreover a corrector step can be added to the integration scheme in many cases such that the remain- der becomes actually of order 4 in εB. A comparison with the fourth-order standard Forest and Ruth integrator [2] is performed showing in general one order of magnitude im- provement in computation precision for the same cost. The construction of these integrators is given for the main mag- netic elements of an electron storage ring.

At the ALS there had been an increasing demand for ad- ditional high brightness hard x-ray beamlines in the 7 to 40 KeV range. In response to that demand, the ALS storage ring was modified in August 2001. Three 1.3 Tesla normal conducting bending magnets were removed and replaced with three 5 Tesla superconducting magnets (Superbends). The radiation produced by these Superbends is an order of magnitude higher in photon brightness and flux at 12 keV than the 1.3 Tesla bends, making them excellent sources of hard x-rays for protein crystallography and other hard x-ray applications. At the same time the Superbends do not compromise the performance of the facility in the UV and Soft X-ray regions of the spectrum. The Superbends will eventually feed 12 new beam lines greatly enhancing the facility's capacity in the hard x-ray region. The Su- perbend project is the biggest upgrade to the ALS storage ring since it was commissioned in 1993. In this paper we present a history of the project, as well as the installation, commissioning, and resulting performance of the ALS with Superbends.

The slow orbit feedback system at the ALS has been con- tinually improved over the years. The most recent upgrades were the incorporation of an RF-frequency feedback and the switch to higher resolution digital to analog converters (DACs). In addition all readouts of beam position moni- tors (BPMs) and most of the controls for corrector mag- net power supplies were ported to a new control system based on compact PCI (cPCI) intelligent output controllers (IOCs). These upgrades were part of the implementation of a new fast global orbit feedback system which has been de- signed over the last year and a half and is entering its com- missioning stage. One feature of the fast orbit feedback (with 1 kHz update rate) is the use of standard computer and networking equipment.

To expand the capabilities of the Advanced Light Source (ALS) and to satisfy the demand for high energy x-ray sources with high brightness, three 1.3 T normal conduct- ing bending magnets were replaced with three 5 T super- conducting magnets (Superbends) in 2001. The new mag- nets will ultimately provide 12 new beam lines for users. The x-ray brightness and flux of the Superbends at 12 keV is more than one order of magnitude higher than the one of the conventional magnets they replaced. The Superbend project was a major upgrade of the ALS since the 3 Super- bends are an integral part of the machine lattice and perturb its original 12-fold symmetry. This paper describes the suc- cessful (and quick) commissioning period and the acceler- ator physics issues associated with the Superbend upgrade (especially the off-energy single particle dynamics).

Particle motion in storage rings is confined by various aperture limits, the size of which restricts the performance of the ring in terms of injection efficiency, lifetime, etc. Intrabeam scattering makes particles sweep a large portion of the phase space, where their motion may eventually be resonantly or chaotically excited to large amplitudes leading to collision with the vacuum chamber. We report here the studies performed at the Advanced Light Source (ALS) on the on- and off-momentum particle motion that provides a good understanding of these limitations. Using off-momentum simulations and experiments together with frequency map analysis, we could precisely correlate beam loss areas with resonance locations. The very good agreement between simulations and experiments allowed us to provide guidance for avoiding these dangerous areas. This analysis results in predictive improvements of the momentum aperture, which actually led to a lifetime increase of 25% at the ALS for very high bunch charge.

The topic of this thesis is the study of beam dynamics in storage rings with a restriction to single particle transverse dynamics. In a first part, tools (Frequency Map Analysis, Hamiltonian, Integrator) are presented for studying and exploring the dynamics. Numerical simulations of four synchrotron radiation sources (the ALS, the ESRF, SOLEIL and Super-ACO) are performed. We construct a tracking code based on a new class of symplectic integrators (Laskar and Robutel, 2000). These integrators with only positive steps are more precise by an order of magnitude than the standard Forest and Ruth's scheme. Comparisons with the BETA, DESPOT and MAD codes are carried out. Frequency Map Analysis (Laskar, 1990) is our main analysis tool. This is a numerical method for analysing a conservative dynamical system. Based on a refined Fourier technique, it enables us to compute frequency maps which are real footprints of the beam dynamics of an accelerator. We stress the high sensitivity of the dynamics to magnetics errors and sextupolar strengths.

The second part of this work is dedicated to the analysis of experimental results from two light sources. Together with the ALS accelerator team (Berkeley), we succeeded in obtaining the first experimental frequency map of an accelerator. The agreement with the machine model is very impressive. At the Super-ACO ring, the study of the tune shift with amplitude enabled us to highlight a strong octupolar-like component related to the quadrupole fringe field. The aftermaths for the beam dynamics are important and give us a better understanding the measured ring performance. All these results are based on turn by turn measurements. Many closely related phenonema are treated such as response matrix analysis or beam decoherence.

The lifetime of a light source with small emittance like the Advanced Light Source (ALS) is usually limited by the momentum acceptance of the ring. Large momentum acceptances are reached by providing enough RF voltage and by avoiding a degradation of the dynamic momen- tum aperture. At the ALS the size of the momentum ac- ceptance depends strongly on the transverse dynamics. It is very sensitive to machine conditions such as the tunes and chromaticities since depending on those conditions the Touschek scattered particles explore different resonance re- gions in the phase space. In this paper we show that by using a single-turn 'pinger' magnet together with turn-by- turn beam position monitors (BPM) one can identify the cause of a reduction in momentum acceptance and take steps to improve the acceptance.

The Frequency Map Analysis (FMA) [1] is a refined nu- merical method based on Fourier techniques which pro- vides a global view of the dynamics of multi-dimensional systems and which was successfully applied to accelerator dynamics starting with the Dumas and Laskar work [2]. Two third generation synchrotron light sources, the SOLEIL Project and the ESRF are studied with this method. A full computation of the dynamic aperture (DA) is performed with a discussion of its inner complex struc- ture (resonances) in correlation with its associated fre- quency map (FM) through diffusion (long term stability criterion). We also underline that despite the large DAs of both machines, the FM shapes are fully distinct due to the high sensitivity of the dynamics to the sextupole strengths.

Particle motion in storage rings is confined by various aperture limits, the size of which restricts the performance of the ring in terms of injection efficiency, lifetime, etc. Intrabeam scattering makes particles sweep a large portion of the phase space, where their motion may eventually be resonantly or chaotically excited to large amplitudes leading to collision with the vacuum chamber. We report here the studies performed at the Advanced Light Source (ALS) on the on- and off-momentum particle motion that provides a good understanding of these limitations. Using off-momentum simulations and experiments together with frequency map analysis, we could precisely correlate beam loss areas with resonance locations. The very good agreement between simulations and experiments allowed us to provide guidance for avoiding these dangerous areas. This analysis results in predictive improvements of the momentum aperture, which actually led to a lifetime increase of 25% at the ALS for very high bunch charge.

To understand the dynamics in an accelerator it is essential to have a good model representing its realistic lattice. One method used at the ALS to calibrate the linear (coupled) accelerator model is the analysis of orbit response matri- ces. Recently this method has been combined with fre- quency map techniques, both in tracking and experiment at the accelerator. Comparing the results of simulated and measured frequency maps shows how accurately the accel- erator model describes the nonlinear beam dynamics. In addition measured frequency maps can serve as a model in- dependent tool to evaluate the quality of a lattice. The mea- surements at the ALS clearly show the network of coupling resonances and the agreement with the simulation using the calibrated model is very good whereas the disagreement is large when using an ideal accelerator model.