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An s-band re-entrant cavity BPM system is designed for new high brightness injector at HLS. A prototype cavity BPM system was manufactured for off-line test, which is also called cold test. According to the results of computer simulation, wire scanning off-line test method can be used to calibrate the BPM and estimate the performance of the on-line BPM system. Cross-talk problem was detected during the cold test. Ignoring nonlinear effect, transformation matrix is a way to correct cross-talk. Analysis of cold test results showed that position resolution of prototype BPM is better than 3 μm., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Linac Energy Management (LEM) is a control system program which calculates, and optionally implements, magnet setpoint settings (BDESs) following a change in Energy (such as a change in the number, phase, and amplitude of active klystrons). The change is made relative to those magnets’ existing BDES setpoints by a factor encoding the change in energy. LEM is necessary because changes in the number, phase, and amplitude of the active klystrons (the so-called "Klystron complement") change the beam’s rigidity, and therefore, to maintain constant optics, one has to change focusing gradients and bend fields. This paper describes the basic process and some of the implementation lessons learned for LEM at the LCLS., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

In this paper we describe the design, installation and first calibration tests of a Multi Optical Transition Radiation (OTR) monitor system in the beam diagnostic section of the Extraction (EXT) line of ATF2, close to the multi wire scanner system. This system will be a valuable tool for measuring beam sizes and emittances from the ATF Damping Ring (DR). With an optical resolution of about 2 um an original OTR design demonstrated the ability to measure a 5.5um beam size in one beam pulse and to take many fast measurements. This gives the OTR the ability to measure the beam emittance with high statistics, giving a low error and a good understanding of emittance jitter. Furthermore the near by wire scanners will be a definitive test of the OTR as a beam emittance diagnostic device. The muti-OTR system design proposed here is based on the existing OTR1X, located after the septums at the entrance of the EXT line., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

We report the design, performance, and installation of the beam diagnostic system of XFEL/SPring-8. The electron beam bunches of an XFEL accelerator are compressed from 1 ns to 30 fs by bunch compressors without emittance growth and peak-current fluctuation which directly cause SASE fluctuation. To maintain the stable bunch compression process, the accelerator requires rf caivty beam position monitors (BPM) with 100 nm resolution, OTR screen monitors (SCM) with a few micro-meter resolution, fast beam current monitors (CT) and temporal structure measurement systems with resolution under picosecond. The performance of the developed monitor instruments, such as the BPM, the SCM, and the CT, was tested at the SCSS test accelerator and satisfied with the requirements. To measure the temporal structure of the electron bunch, three type measurement systems, which are a streak camera, an EO sampling measurement, and a transverse deflecting cavity with a resolution of few-tens femtosecond, are being prepared. The streak camera and EO sampling shows the resolution of sub-picosecond. The installation of these beam diagnostic systems is going on smoothly., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Some of the improvement were done for an SR interferometer with the Herschelian reflective optics*. Previously, the measured vertical beam size was limited to around 5μm with a double slit separation of 40mm and wavelength of 400nm at the ATF damping ring. Double slit separation was mainly limited to the effective aperture of the optical path between the source point and interferometer. This time, we re-aligned the optical path, and as a result, the effective aperture was increased. Using this re-alignment we can have a double slit separation of up to 60mm. To reduce air turbulence, the optical path was covered with a tight air duct. After these improvements were made, we succeeded in measuring a vertical beam size of 3.4μm with double slit separation of 60mm and wavelength of 550nm, which corresponds to 5pm of the vertical emittance assuming 3m of the beta function., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A compact remote control system with the SIMATIC S7-300 PLC is being designed for Peking University Neutron Imaging FaciliTY (PKUNIFTY). PKUNIFTY consists of a 2.45GHz ECR Deuteron ion source, LEBT, a 201.5MHz RFQ cavity, HEBT and Be target. Now PLC control system for ECR ion source and LEBT has been completed and tested. This paper will present the structure of the control system, the HMI with useful data recording system, and some measures took to improve the system safety., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The proposed Compact Linear Collider (CLIC) is based on a two-beam acceleration scheme. The energy of high intensity, low energy drive beams is extracted and transferred to low intensity, high energy main beams. Direct ionization loss by the beam particles is the principal damage mechanism. The total charge gives a single drive beam-train a damage potential that is two orders of magnitude above the level causing structural damage in copper. For the main beam, it is the extreme charge density due to the microscopic beam size that gives it a damage potential of four orders of magnitude above the safe level. The machine protection system has to cope with a wide variety of failures, from real time failures (RF breakdowns, kickers misfiring), to slow equipment failures, to beam instabilities (caused by e.g. temperature drifts, slow ground motions). This paper discusses the baseline for the CLIC machine protection system which is based on passive, active and permit based protection. As the permit based protection depends on the measured performance of the previous pulse, the bootstrap procedure with safe beams and stepwise increase in beam intensities, is also discussed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

We consider the particles energy measurement method offered in our papers (footnotes). It is based on measurement of the modes frequencies in waveguide loaded with certain material. For this method, the modes frequencies must depend on the particles energy strong enough. Here we discuss the problem of selection of materials for this technique. It is shown that high precision of energy measurement can be reached by use of the system of specific parallel conductors. The approximate analytical approach for obtaining effective permittivity of such structure is developed. It is shown that selection of parameters of the structure allows ruling an effective permittivity characterized by both frequency dispersion and spatial one. The structure is simple enough for production. It allows measuring the particles energy for different predetermined ranges. The other ways of realization of the method are discussed as well. One of them consists in use of thin layer of ordinary dielectric. Selection of the layer thickness and dielectric constant allows obtaining strong enough dependence of frequency on Lorentz-factor in the relatively wide range., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The SPS exponential coupler stripline are used to study single bunch instabilities. An accurate description of the response of the pickup is required to obtain high resolution measurements of the bunch vertical motion along the longitudinal axis. In this study we present the results of the comparison between dedicated beam experiments and electromagnetic simulations of a geometrical model of the stripline., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Experiences of operating BPM’s during beam commissioning at the J-PARC MR are reported. The subjects are: (1) bug report, statistics and especially the effect of a beam duct step, (2) position resolution estimation (30 micrometers with 1 sec averaging), (3) beam based alignment., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Most of the magnet power supplies of the KEKB rings and beam transport lines are connected to the local control computers through ARCNET. For this purpose we have developed the Power Supply Interface Controller Module (PSICM), which is designed to be plugged into the power supply. It has a 16-bit microprocessor, ARCNET interface, trigger pulse input interface, and parallel interface to the power supply. According to the upgrade plan of the KEKB accelerators, more power supplies are expected to be installed. Although the PSICMs have worked without serious problem for 11 years, it seems too hard to keep maintenance for the next decade because some of the parts have been discontinued. Thus we decided to develop the next generation of the PSICM. Its major change is the use of the Ethernet instead of the ARCNET. On the other hand the specifications of the interface to the power supply are not changed at all. The new PSICM is named ePSICM (Ethernet-based Power Supply Interface Controller Module). The design of the ePSICM and the development of the prototype modules are in progress., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

FERMI@Elettra is a new 4th-generation light source based on a single pass free electron laser. It consists of a 1.5-GeV normal-conducting linac working at 50 Hz repetition rate and two chains of undulators where the photon beams are produced with a seeded laser multistage mechanism. A number of control loops, some of them working on a shot by shot basis, are required to stabilize the crucial parameters of the beams. For this purpose, a generalized real-time framework integrated in the control system has been designed to flexibly and easily implement feedback loops using several monitoring and control variables. The paper discusses the requirements of the control loops and the implementation of the feedback framework. The first closed loop results and the experience gained in the operation of the feedbacks during the first phase of the machine commissioning will also be presented., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Luminescent screens are widely used for particle beam diagnostics, especially in transverse profile measurements at hadron machines and low energy electron machines where the intensity of optical transition radiation (OTR) is rather low. The experience from modern linac based light sources showed that OTR diagnostics might fail even for high energetic electron beams because of coherence effects in the OTR emission process. An alternative way to overcome this limitation is to use luminescent screens, especially inorganic scintillators. However, there is only little information about scintillator properties for applications with high energetic electrons. Therefore a test experiment has been performed at the 855 MeV beam of the Mainz Microtron MAMI (University of Mainz, Germany) in order to study the spatial resolution. The results of this experiment will be presented and discussed in view of scintillator material properties and observation geometry., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Proton beam extinction, defined as a residual to primary ratio of beam intensity, is one of the most important parameters to realize the future muon electron conversion experiment (COMET) proposed at J-PARC. To achieve the required extinction level of 10⁻⁹, we started measuring beam extinction at main ring (MR) as the first step. The newly developed beam monitor was installed into the abort beam line and the first measurement was successfully performed by using the fast-extracted MR beam. We found that empty RF buckets of RCS, in which all protons were considered to be swept away by a RF chopper before injection to RCS,, contained about 10⁻⁵ of the main beam pulse due to chopper inefficiency. We are now developing a new beam monitor with improved performance for further studies at the abort line. In addition, we have started new measurements at the different stage of proton acceleration, i.e. at Linac, 3-50 BT line, and the main ring. In this paper, we present recent results and future prospect of beam extinction measurements., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The Data Acquisition System of Beam Position Monitors(BPMs) in J-PARC Main Ring are consist of 186 Linux-based Data Processing Cirquits(BPMCs) and 12 EPICS IOCs. They are important tool to see the COD and turn-by-turn beam positions. This report describes the process of the data reconstruction which include how the various calibration constants are applied., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

sFLASH is a seeded FEL experiment at DESY, which uses a 38nm high harmonic gain (HHG)-based XUV-beam laser in tandem with FLASH electron bunches at the entrance of a 10m variable-gap undulator. The temporal overlap between the electron and HHG beams is critical to the seeding process. Use of a 3rd harmonic accelerating module provides a high current electron beam (at the kA level) with ~ 600fs FWHM bunch duration. The length of the HHG laser pulse will be ~30fs FWHM. The desired overlap is achieved in steps. First is the synchronization of the HHG drive laser (Ti: Sapphire, 800nm) and the incoherent spontaneous radiation from an upstream undulator. Next, the IFEL-modulated electron bunch will pass through a dispersive section, producing a density modulation in the beam. This in turn yields emission of coherent radiation from a downstream undulator or transition radiation screen when the longitudinal overlap of the two beams is achieved. The coherently enhanced light emitted will be then spectrally analyzed. The experimental layout, simulation results of generation and transport of both light pulses, and preliminary measurements are presented., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The accelerator safety interlock system of XFEL/SPring-8 was designed to fulfill the requirement of matching with the safety interlock system of SPring-8 because both safety systems are planning to be unified in near future to deal with the electron beam injection from XFEL to SPring-8. At XFEL, however, additional requirements for the system also existed; the designed radiation shielding requires when the electrons are not injected into the dump core properly, the beam has to be terminated within 16 msec, which corresponds to 60 Hz operation, to avoid the next bunch coming. An outline of such different design criteria is presented together with the concept of the safety interlock system. The radiation monitoring system, which was also the same as that of SPring-8, was installed by reinforcing the redundancy and response time. Gamma and neutron monitors are set at 14 positions near the assumed loss points in the accessible place of the controlled area. The dose equivalent data are sent to the radiation monitoring systems of XFEL and SPring-8, respectively, and when the measured dose exceeds the preset level, an alarm signal is sent to the safety interlock promptly., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A new laser-based alignment system is under development at the KEKB injector linac. We are revisiting our alignment system because the previous alignment system has become obsolete. The new alignment system is again required to increase the stability of the electron- and positron-beam injection towards next-generation of B-factories. It is similar to the previous one, which comprises a laser-diode system and quadrant photodetectors installed in vacuum light pipes. A displacement of a girder unit of the accelerating structure can be precisely measured in the direction of the laser-ray trace, where the laser light must stably propagate up to 500-m-long downstream without any orbital and beam-size fluctuation. A novel approach in which a two-beam-interference laser-light propagates in the vacuum light pipe, has been designed to increase the alignment precision based on the quadrant photodetector measurement. The propagating laser spot sizes can be narrowed due to the two-beam interference over the Rayleigh-range limit. The design of the new laser-based alignment system is summarized along with some experimental results in this report., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The talk will provide an overview of required feedback systems to guarantee stable and successful SASE operation as well as successful experiments. Recent developments and examples of various systems (including feedbacks for long bunch trains) will be discussed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

To maintain the beam orbit of beam transport line from RCS to MR in J-PARC (3-50BT), 14 beam position monitors (BPMs) were installed. Their signals gathered in the local control building (D01) have been measured by using 14 digitizing oscilloscopes. The data acquisition system have a performance of shot-by-shot measurement., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A 3GeV Rapid-Cycling Synchrotron (RCS) in Japan Proton Accelerator Research Complex (J-PARC) has continuously provided more than 100kW proton beam to the Neutron target since October 2009. And we also successfully accelerated 300kW beam for one hour on December 10th by way of trial. We found some problems through these experiences. We report those problems and the residual dose in such high intensity operation., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Ultra-short electron bunch production is attractive for a large number of applications ranging from short wavelength free electron lasers (FEL), THz radiation production, linear colliders and plasma wake field accelerators. SPARC is a test facility able to accelerate high brightness beam from RF guns up to 150 MeV allowing a wide range of beam physics experiments. Those experiments require detailed beam measurements and careful data analysis. In this paper we discuss the techniques currently used in our machine; by combining quadrupoles, RF deflector, spectrometer dipole and reliable data analysis codes, we manage to characterize the 6D phase space and the beam slice properties. We focus on the ongoing studies on the emittance compensation in the velocity bunching regime., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The CLIC study is based on the so-called two-beam acceleration concept and one of the main goals of the CLIC Test Facility 3 is to demonstrate the efficiency of the CLIC RF power production scheme. As part of this facility a Test Beam Line (TBL), presently under commissioning, is a small scale version of a CLIC decelerator. To perform as expected the beam line must show efficient and stable RF power production over 16 consecutive decelerating structures. As the high intensity electron beam is decelerated its energy spread grows by up to 60%. A novel segmented beam dump for time resolved energy measurements has been designed to match the requirements of the TBL. As a complement, a diffusive OTR screen is also installed in the same spectrometer line. The combination of these two devices will provide both a high spatial resolution measurement of both the energy and energy spread and a measurement with a few nanoseconds time response. This paper describes the design of the new segmented dump and presents the results from the first commissioning of the TBL spectrometer line., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Synchrotron radiation is currently used on LHC for beam imaging and for monitoring the proton population in the 3 microsecond abort gap. In addition to these existing detectors, a study has been initiated to provide longitudinal density profiles of the LHC beams with a high dynamic range and a 50ps time resolution. This would allow for the precise measurement both of the bunch shape and the number of particles in the bunch tail or drifting into ghost bunches. A solution is proposed based on counting synchrotron light photons with two fast avalanche photo-diodes (APD) operated in Geiger mode. One is free-running but heavily attenuated and can be used to measure the core of the bunch. The other is much more sensitive, for the measurement of the bunch tails, but must be gated off during the passage of the core of the bunch to prevent the detector from saturating. An algorithm is then applied to combine the two measurements and correct for the detector dead time, after pulsing and pile-up effects. Initial results from laboratory testing of this system are described in this paper., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The Super-FRS is a superconducting fragment separator that will be built as part of the FAIR facility. For the slow-extraction part of the beam diagnostics system a total of 32 detectors are needed for beam monitoring and for tracking and characterization of the produced ions. Since GEM-TPC detectors can perform over wide dynamic range without disturbing the beam, they are suitable for this kind of in-beam detection. We have studied the performance of a prototype GEM-TPC. The current status of the prototype detector and the measurement results are shown., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Gazing at SuperKEKB project, a new control subsystem was designed and implemented to upgrade the low level RF system of the KEKB accelerator based on Experimental and Industrial Control System (EPICS). The new control subsystem comprises a uTCA, a PLC, and an industrial PC. Each card plugged in the uTCA chassis and the PLC function as an embedded Input / Output Controller (IOC) by running the EPICS core program on the Linux operating system. The industrial PC runs Extensible Display Manger on Linux to serve as an Operator Interface (OPI). This paper describes the details of the design and the implementation of the fully embedded EPICS-based low level RF control subsystem for SuperKEKB., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The accelerator safety interlock system (ASIS) for the XFEL/SPring-8 protects personnel from radiation hazard. We designed the ASIS consisting of three independent systems; a central interlock system, an emergency interlock system and a beam route interlock system. The central interlock system monitors the machine tunnel security, status of beam line interlock system and radiation monitoring system. The emergency interlock system monitors status of emergency stop buttons. The beam route interlock system monitors electron beam route by inputting the current of the bending magnets at the electron-beam switching points. If any system trips, or if any system detects unsafe status, the permission signal for the accelerator operation from the system is off and the electron beam is inhibited. In addition, it is demanded that the permission signals must be transmitted within 16.6 ms. Therefore, the stability and fast response are required for the XFEL safety interlock system. We adopted programmable logic controllers (PLC) for the stability, and developed optical modules for the fast signal transmission. This paper describes system design of the ASIS., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

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., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The demonstration of the stability of the position of the focused beam is a primary goal of the ATF2 project. We have installed a laser interferometer system that will eventually correct the measurement of high-precision Beam Position Monitors used in the ATF2 Final Focus Steering Feedback for mechanical motion or vibrations. Here, we describe the installed system and present preliminary data on the short- and long-term mechanical stability of the BPM system., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

FERMI@Elettra is a soft X-ray fourth generation light source under construction at the ELETTRA laboratory. To characterize the beam phase space by means of measurements of the bunch length and of the transverse slice emittance two deflecting cavities will be positioned at two points in the linac. One will be placed at 250 MeV (low energy), after the first bunch compressor (BC1); the second at 1.2 GeV (high energy), just before the FEL process starts. The Low-Energy RF Deflector consists in a 5 cells, standing wave, normal conducting, RF copper cavity. A single ANSYS model has been developed to perform all of the calculations in a multi-step process. In this paper we discuss and report on results of electromagnetic, thermal, and structural analysis., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The EPICS embedded programmable logic controller (PLC) has been developed based on F3RP61-2L, a CPU module of a FA-M3R series PLC running Linux OS. The EPICS IOC resided in F3RP61-2L module can access the registers of sequence CPU modules and I/O modules of the PLC. The embedded EPICS PLC was applied to control the prototype of pulse magnet power supply and support functionality testing remotely. The system comprises various input/output modules and a CPU module with built-in Ethernet interface. The control information (status of the power supply, ON, OFF, warn up, reset, read/write voltage, etc.) can be accessed remotely using EPICS client tools. The EDM is selected to develop the GUI for itself. Efforts are summarized in this report., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The prototype of an analog transverse (vertical and horizontal) feedback system to actively damp the electron-proton (e-p) instability has been developed and tested on the ORNL Spallation Neutron Source (SNS). We will describe the principle components, system configuration, and review several experimental studies geared towards understanding the current performance and limitations of the system., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Transverse bunch by bunch feedback systems for J-PARC MR accelerator has been designed and tested. Bunch positions are detected by Log-ratio position detection systems with center frequency of 12 MHz. The digital filter which consists of two LLRF4 boards samples the position signal with 64 times of RF frequency. Up to four sets of 16 tap FIR filter with one-turn delay and digital shift gain can be used. Preliminary results of beam test of the system are also shown., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A wire scanner monitor (WSM) is one of essential measurement devices for beam commissioning of current accelerators. J-PARC Linac also employs a number of WSMs for transverse beam profile. The transverse matching is performed based on the measured beam width. In addition, we have tried to measure halo component with the BSMs. In this paper, we present the experimental results obtained in a beam study to characterize the operational performance of the WSM., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Future atomic and nuclear physics experiments put challenging demands on the required beam instrumentation. Low energy (1 MeV), low intensity (10⁷ pps) beams will require highly sensitive monitors. This is especially true for the Facility for Low-energy Antiproton and Ion Research (FLAIR) where antiproton beams will be decelerated down to 20 keV and as few as 5·10⁵ particles per second will be slowly extracted for external experiments. In order to investigate the limits of scintillating screens for beam profile monitoring in the low energy, low intensity regime a structured analysis of several screen materials, including CsI:Tl, YAG:Ce and scintillating fibre optic plate (SFOP), has been done under different irradiation conditions with keV proton beams. This contribution will present the experimental setup and summarize the results of this study., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Profile shape measurements detecting profile slope angle, which corresponds to the differential of the profile shape, have been used for evaluating profile shapes highly precisely. They are hardly affected by scanning error in measurement and considered to have advantages for long distance measurements. Here, profile measurement using a level was adopted for straightness alignment of the KEK e⁻/e⁺ injector linac, considering the straightness alignment as a profile shape measurement. The slope angles between the alignment base plates of the linac could be detected with reproducibility of 10 micro-rad (σ) by sequential measurement interval of 1 to 2 m. The reproducibility of the straightness derived from the angle measurements was 42 micrometer (σ) for 69 m of the measurement distance and agreed well with the estimated value based on our error propagation model. These results show that straightness reproducibility of better than 1 mm (2-σ) can be achieved for 500 m of the KEK e⁻/e⁺ injector linac by sampling interval of 2m, and for 10 km of the ILC linac by sampling interval of 20 cm., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

This paper reports on the progress of the development of a bunch length diagnostic for high brightness beams. The diagnostic, termed the real time interferometer, is a single shot, autocorrelator that outputs the interferogram of coherent radiation emitted from compressed, high-brightness beams. The device uses all-reflective terahertz optics as well as a highly sensitive pyroelectric-based detector array. For initial testing, coherent transition radiation is used, however, the diagnostic can be used in a non-destructive manner if coherent edge or synchrotron radiation is employed. Current research includes diagnostic design and preliminary tests conducted at the BNL Accelerator Test Facility., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Commissioning of spin flipper in the RHIC (Relativistic Heavy Ion Collider) Blue ring during the 2009 RHIC polarized proton run showed significant global vertical coherent betatron oscillations induced by a two AC dipole plus four DC dipole configuration. These global orbital coherent oscillations affected collision rates and Yellow beam polarization when beams were in collision. The measured depolarizing strength of of the two AC dipoles at a phase difference of 180 degrees at injection with a different spin tune also confirmed that a single isolated spin resonance can not be induced in the presence of this global vertical coherent betatron oscillation. Hence, a new design was proposed to eliminate the coherent orbital oscillation outside the spin flipper with three additional AC dipoles. This paper presents the new design and supporting numerical simulations. In the RHIC 2010 Au run, only one AC dipole was inserted between the two original AC dipoles; and the measured closure of this AC dipole bump is also presented., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Thirty two Bergoz Beam Position Monitors are located in the Australian Synchrotron booster ring. They currently suffer from a poor signal-to-noise ratio and a low sample rate data acquisition (DAQ) system, provided by a portable DAQ device. This architecture is being upgraded to offer better performance. Phase matched low attenuation cables are being pulled and readout electronics will be located in two sites to reduce cable length. Data acquisition will be upgraded using a high accuracy PCI DAQ board. The board’s trigger, originally delivered by a Delay Generator, will be generated by an Event Receiver output following our recent upgrade of the timing system. The new Linux driver will be EPICS-based, for consistency with our control system., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A set of 16 Inductive Pick-Ups (IPU) for Beam Position Monitoring (BPM) with its associated electronics were designed, constructed and characterized at IFIC for the Test Beam Line (TBL) of the 3rd CLIC Test Facility (CTF3) at CERN. In October 2009 the full set of IPUs, (BPS) was successfully installed in the TBL line. In this paper, we describe the prototyping and series production phases of the BPSs development, focusing in the implementation and the results analysis derived from their characterization tests. Two special test benches were designed and built to perform the characterization tests at low and high frequencies. The low frequency set up based on a wire-method test bench for emulating the beam position variations helped us to determine the BPS performance parameters at beam pulse time scale from 100μs/10kHz to 10ns/100MHz. On the other hand, the high frequency test setup, based on an adapted coaxial transmission line, was dedicated to obtain the BPS longitudinal coupling impedance at the beam microbunches time scale (83ps/12GHz). Furthermore, we also present the first beam performance tests made in the TBL line., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Optical beam measurement such as OTR(Optical Transition Radiation), ODR(Optical Diffraction Radiation), gas Cerenkov, and so on is a powerful tool to observe a two-dimensional information of high intensity beam profile, so that this method is widely used at various electron and hadron accelerators. However, high radiation field to damage an optical system gradually becomes a major issue with increasing the beam intensity to explore new physics. Our present effort is devoted to develop a high efficient optical system to resist such high radiation field. We newly designed an optical system composed of two spherical mirrors which do not have any lenses vulnerable to radiation. Detailed optics design and a result of optical performance test will be presented. Also we will report a result of a beam test experiment of this optics system combined with an OTR screen performed at high intensity proton extraction beamline of the J-PARC., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan