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A gas-jet monitor has been developed and commissioned by the QUASAR Group at the Cockcroft Institute, UK. It is designed to measure the transverse profile of a beam by crossing it with a neutral supersonic gas-jet. An array of high voltage electrodes is used to extract ions from the region where the beam and gas-jet interact. These ions first hit a micro-channel plate (MCP) and are then imaged through a phosphor screen and a CCD camera. It is important to understand and characterise the measured ion distribution in order to extract the beam profile. Therefore, numerical investigations using the commercial COMSOL and OPERA codes were carried out benchmarking profile measurements obtained from a low energy electron beam. This paper presents results from these studies. It compares measurements based on the interaction of the primary beam with the residual gas or the ultra-cold gas curtain, and discusses the comparisons of simulated profiles and extraction field configurations on the measured profile., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

A new data acquisition system has been developed to improve band-width and dynamic range of the beam loss monitor systems. It consists of isolation current amplifiers with the gain of 1M and the band-width of DC-100kHz, and VME-based 24bit ADCs with the band-width of DC-300kHz and the noise level of 100uV peak to peak. The waveform data of 1MS/s and 1KS/s, and the charge count which is the integrated waveform data are generated and these are compared with alarm levels for the machine protection system. Long-term ground-level stability is essential to monitor residual dose activities. Some beam loss signals include effect of radiations from activated devices, and thus its fractions should be excluded. If the residual dose activities just before the beam injections can be monitored, these fractions would be roughly estimated. Furthermore, on-line monitoring of the residual dose activities after a beam operation will be useful for activation control of the devices at the high level activation area like the collimator and the slow-extraction area. A shot by shot DC offset cancellation is adopted to ensure high ground level stability., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

When a laser pulse with focused intensity exceeding 1018W/cm² interacts with a solid target, electrons in the focal spot are accelerated to relativistic velocity and where they generate inner-shell vacancies and hard x-ray(>10 keV) spectral line and Bremsstrahlung radiation. In laser plasma interactions, the resonance between betatron motion of electrons and ultraintense laser pulses is an interesting phenomenon in both electron acceleration and gamma photon production. Even though the gamma-ray synchrotron is micron scale, the energy ranges from ~1 MeV to ~102MeV. To detect the energy of the gamma-ray accurately is particularly significant. Owing to a lot of various energy of gamma-ray are emitted in femtosecond scale, which are impossible distinguished from each other on the time. A small freon-filled bubble chamber is being built to measure the energy spectrum of high-energy photons. After that, we can calculate the electron’s energy and then offer the data for various of electron acceleration theories. It combines a good spatial resolution with a large depth of field, allowing a large number of tracks. This improves the statistical quality of the photon spectrum., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Conceptual design of an imaging system for the ESS proton beam current density on target is presented. The window separating the linac HV from the 1bar He-filled target station will be used as a source for imaging by means of either OTR or luminescence. The system presents many challenges to be addressed. The window and the primary optics will be exposed to extremely high radiation doses, providing heat cycles and mechanical stresses near the engineering limits, but also may change the surface properties of the window and the optics. The window lifetime expected to be less than 1 year will have to be replace bi-annually, imposing remote handling design for the window but also for part of the optics. In addition, the imaging system should be able to form an image from low to high current beam operations, in order to retrieve beam profile distribution and power density distribution of both static and raster beam, imposing a large numerical aperture (NA), but also to transport the image at more than 15m distance where radiation level is compatible with camera and pc stable operation and human access during commissioning and neutron production., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

We discuss a spectrometer to analyze the electrons and ions ejected from a high-gradient CLIC accelerating structure that is installed in the klystron-driven 12 GHz test-stand at CERN. The charged particles escaping the structure provide useful information about the physics of the vacuum breakdown within a single RF pulse. The spectrometer consists of a dipole magnet, a pepper-pot collimator, a fluorescent screen and a fast camera. This enables us to detect both transverse parameters such as the emittance and longitudinal parameters such as the energy distribution of the ejected beams. We can correlate these measurements with e.g. the location of the breakdown inside the structure, by using information from the measured RF powers, giving in that way a complete picture of the vacuum breakdown phenomenon. The spectrometer was installed during Spring 2014 and will be commissioned during Summer 2014., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Monitors that use plastic scintillator (scintillation monitors) were fabricated to measure the energy and longitudinal profiles of heavy-ion beams at the RIKEN RI beam factory (RIBF).Six pairs of scintillation monitors (12 monitors) installed in the transport lines were used to measure the particle time-of-flight (TOF) to determine the acceleration energy of the heavy-ion beams. In addition, five scintillation monitors were installed to optimize the phase between the rebuncher cavities and the beam for the beam injection to the cyclotrons. Longitudinal beam profiles were obtained by using a time-to-digital converter (TDC), which digitizes the detected signals from the scintillator and the RF clock. The energy of the beam can be calculated from the measured TOF of the beam by using a scintillation monitor pair. Recently, to help users operate the system more easily, a new embedded processor with a higher-performance CPU was introduced, and LabVIEW programs were newly written or greatly improved. Development of the scintillation monitor system and results of experimental measurements of heavy-ion beams are reported., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

We report on the design and performance of coded aperture optics elements in the CesrTA x-ray beam size monitor (xBSM). Resolution must be sufficient to allow single-turn measurements of vertical beam sizes of order 10um by imaging synchrotron radiation photons onto a one-dimensional photodiode array. Measurements with beam energies above 2.1GeV and current above 0.1mA can be performed with a single-slit (pinhole) optic. At lower energy or current, small beam size measurements are limited by the diffractive width of a pinhole image and counting statistics. A coded aperture is a multi-slit mask that can improve on the resolution of a pinhole in two ways: higher average transparency improves counting statistics; and the slit pattern and masking transparency can be designed to obtain a diffractive image with narrower features. We have previously implemented coded apertures that are uniform redundant arrays (URA). A new coded aperture design is optimized for imaging with 1.8 GeV beam energy (1.9keV average x-ray energy) and with beam sizes below 20um. Resolution measurements were made in December 2013. Performance of the new coded aperture is compared to the pinhole and the URA., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The Swiss Light Source (SLS) campaign on vertical emittance minimization and measurement required a beam size monitor with the ability to verify a sub-pmrad vertical emittance. This corresponds to a beam height of less than 4 μm. Within the TIARA Work Package ‘SLS Vertical Emittance Tuning’ a new beam size monitor was designed and built. The monitor is based on the imaging of the pi-polarized synchrotron radiation (SR) in the visible and UV spectral ranges. Besides imaging the monitor provides interferometric methods using vertically or horizontally polarized SR. With these complementary methods the consistency of beam size measurements is verified. An intermediate configuration of the monitor beamline using a lens as the focusing element has been commissioned in 2013. With this setup a vertical beam size of 4.8±0.5 μm, corresponding to a vertical emittance of 1.7±0.4 pmrad has been measured. During 2014 the monitor was commissioned in its final configuration with a toroidal mirror. The use of reflective optics allows wider bandwidth imaging and thus higher intensity. We report on challenges during commissioning and present first images of SR taken with the toroidal mirror., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Measurements of reflected/generated on oscillating wire secondary particles/photons in synchronism with oscillating wire frequency are proposed to done. The differential signal on wire maximal deviations at oscillation process can provide a fast signal proportional to beam profile gradient. Idea of usage of such “Resonant Target” for beam transversal gradient investigation was tested with lightening the oscillating wire by a laser., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

In a synchrotron light source like SOLEIL, Beam Position Monitors (BPM) are optimized to have the highest sensitivity for an electron beam passing nearby their mechanical center. Nevertheless, this optimization is done to the detriment of the response linearity when the beam is off-centered for dedicated machine physic studies. To correct for the geometric non-linearity of the BPM, we have applied an algorithm using boundary element method. Moreover the BPM electronics is able to provide position data at a turn-by-turn rate. Unfortunately the filtering process in this electronics mixes the information from one turn to the neighboring turns. An additional demixing algorithm has been set-up to correct for this artefact. The paper reports on performance and limitations of those two algorithms that are used at SOLEIL to correct the BPM data., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The use of Smith-Purcell radiation to measure electrons longitudinal profiles has been demonstrated at several facilities in the picosecond and sub-picosecond range. There is a strong interest for the development of non intercepting longitudinal profile diagnostics for high current proton beams. We present here results of simulations on the expected yield of longitudinal profile monitors using Smith-Purcell radiation for such proton beams., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

A 14MeV Linac with both the micro-pulse repetition rate 2856MHz and the macro-pulse width 6us for the THz Source Based FEL was proposed. In order to measure the beam position, a stripline beam position monitor (BPM) was designed, and a commercial BPM electronics Libera Brilliance Single Pass was adopted. As the input carrier frequency of the BPM electrode signal is 2856MHz, but the operating frequency of the Libera Brilliance Single Pass is 500MHz, so a front-end electronics was needed before the electrode signals feed into Libera Brilliance Single Pass. The front-end electronics was designed to make the BPM electrode signals of 2856MHz convert to 500MHz., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

For the upgrade of the accelerator facility ELSA towards higher stored beam currents, a non-destructive beam analysis is being implemented at the 2.5 GeV booster synchrotron. It is a fast ramping combined function synchrotron with an extraction repetition rate of 50 Hz. Typically, beam currents of 10 mA are accelerated from 20 MeV to the extraction energy of 1.2 GeV within 8.6 ms, hence the magnetic field is increased by up to 85 T/s. A synchrotron light monitor as the primary diagnostic tool will be utilized for measuring the transversal position and intensity distribution of the beam. Its dynamics on the fast energy ramp is of distinct interest. The proposed set-up of the synchrotron light monitor and the current development are presented., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

We are developing a diamond detector for beam halo and Compton spectrum diagnostics after the interaction point (IP) of ATF2, a low energy (1.3 GeV) prototype of the final focus system for ILC and CLIC linear collider projects. Tests of a 500 μm thick sCVD diamond detector with a dimension of 4.5 mm×4.5 mm have been carried out with radioactive sources and with electron beam from PHIL low energy (, Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The Beam Current Monitor system of the ESS linac will be mainly based on AC Current Transformers. The BCM system will be used to monitor the beam current and charge in absolute and differential modes. The differential current measurement is also intended for detecting large and sudden beam losses and acting on the Machine Interlock System (MIS), especially in areas where Beam Loss Monitors cannot be reliably used. A demo BCM based on a Bergoz ACCT and MTCA.4 electronics has been procured and integrated into EPICS. A VHDL code has been developed and successfully tested for the required FPGA signal processing including droop compensation, filtering, DC level correction and interfacing to the MIS. This paper gives an overview of the current status of the BCM system design and implementation as well as some preliminary test results in absolute and differential modes., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

As part of the CERN LHC injector chain upgrade, LINAC4 will accelerate H⁻ ions to 160 MeV, replacing the old 50 MeV proton linac. The ion source, the Low Energy Beam Transfer (LEBT) line, the 3 MeV Radio Frequency Quadrupole and the Medium Energy Beam Transfer (MEBT) line hosting a chopper, have been first commissioned in a dedicated test stand and are now tested in the LINAC4 tunnel. Diagnostics devices are installed in the LEBT and MEBT line and in a movable diagnostics test bench which is temporarily added to the MEBT exit. The paper gives an overview of all the instruments used, including beam current transformers, beam position monitors, wire scanners and wire grids for transverse profile measurements, a longitudinal bunch shape monitor and a slit-and-grid emittance meter. The movable test bench also includes a spectrometer that allows measuring the beam energy spread in conjunction with a wire grid. The present understanding of the instrumentation performance is discussed and the measurement results that allowed characterizing the 3 MeV beam in the LINAC4 tunnel are summarized., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Optical Transition Radiation (OTR) is emitted when a charged particle crosses the interface between two media with different dielectric properties. It has become a wide-spread method for beam profile measurements. However, there are no tools to simulate the propagation of the OTR electric field through an optical system. Simulations using ZEMAX have been performed in order to quantify optical errors, such as aberrations, diffraction, depth of field and misalignment. This paper focuses on simulations of vertically polarized OTR photons with the aim of understanding what limits the resolution of realistic beam imaging systems., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The Heidelberg Ion Therapy Center (HIT) is a heavy ion accelerator facility located at the Heidelberg university hospital and intended for cancer treatment with heavy ions and protons. Currently ionization chambers with highly sensitive charge amplifiers are regularly used for intensity measurements of the high-energy ion beams. A new intensity measuring method will be presented based on the combination of fluorescent light from inorganic scintillators and an optoelectronic sensor with adjacent electronics as an alternative to the ionization chambers. A special measurement set-up with a large-area Si PIN-diode and adapted optics was investigated with respect to signal dynamics, resolution and linearity. The experimental results with proton and carbon beams will be presented in detail. Worth mentioning is a variation in sensitivity relating to the position of the beam spot, which could be reduced to some percent only., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Precise and fast beam size measurement and emittance reconstruction in the different subsystems and transfer lines of the Future Linear Colliders (ILC and CLIC) will be essential for beam tuning in order to achieve the required luminosity. In this paper we investigate the feasibility of using a multi-Optical Transition Radiation (m-OTR) system for fast transverse beam size measurement, emittance reconstruction and coupling correction in the Ring to Main Linac (RTML) of the FLCs. Diagnostic sections of the RTML have been matched to the optimum optical conditions for emittance reconstruction. The necessary requirements for the OTR monitors to be placed in the RTML are discussed., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

In order to nondestructively measure the beam energy spread with a beam energy of 0.8GeV in the injector at the upgrade project of Hefei Light Source (HLS II) in real time, a beam energy spread monitor (BESM) using beam position monitor (BPM) with four stripline electrodes has been developed. And a screen monitor (SM) near the BESM is used to measure beam energy spread destructively. This paper introduces in brief the beam position measurement system and beam transverse profile measurement system. The relationship between the transverse size at the BESM and at the SM (Flag3) is discussed in detail in this report. The result shows that energy spread measuring result of BESM and SM is 0.19% and 0.18% respectively. So we can draw a conclusion that the BESM is capable of nondestructively measuring the beam energy spread., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Two non-invasive beam profile measurement methods were developed for China high intensity proton beams projects, including CSNS and ADS. The first consists in an IPM (ionization beam profile monitor) system which detect the ionized products from a collision of the beam particle with residual gas atoms or molecules present in the vacuum pipe. The second is an electron beam scanner which using a low energy electron beam instead of a metal wire to sweep through the beam. The deflection of electron beam by the collective field of the high intensity beam is measured. The charge density in the high intensity beam can be restored under certain conditions or estimated by various mathematical techniques. Here we present the design parameters of the IPM system, the signal intensity of ionization products, optimization of the electric field, machine designs of electrode, tracking of the ionization products and so on. The principle of the electron beam scanner and the test results which is based on a commercial electron gun from Kimball Physics are also introduced in details., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

A new linac, named REGAE (Relativistic Electron Gun for Atomic Exploration) has been built at DESY and operates as an electron source for ultra-fast electron diffraction. An RF photocathode gun provides electron bunches of high coherence, sub-pC charge and energies of 2-5 MeV. In order to film time-resolved structural changes of excited specimens, bunch lengths of several femtoseconds need to be created. Taking into account these critical parameters, beam diagnostics at REGAE is very challenging. The existing diagnostics consists of energy, energy spread, beam profile, beam charge and emittance measurements. For transversal diagnostics, specific approaches have to be considered to overcome complications associated with the low charge and to carry out the beam diagnostics in single shot. In this paper, the contribution of the transversal diagnostics to the measurement of the transverse emittance is presented., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

CERN is currently constructing an Extra Low ENergy Antiproton ring (ELENA), which will allow the further deceleration of antiprotons from the currently exploited Antiproton Decelerator (AD). In order to meet the challenges of ELENA the beam instrumentation systems of the CERN AD are being consolidated and upgraded. An updated controls architecture with a more flexible timing system needs to be adopted and obsolete systems must be replaced. This paper presents the status and plans for improved performance and measurement availability of the AD beam instrumentation with a decreased risk of failure., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Coherent synchrotron radiation (CSR) in the terahertz frequency range is a powerful tool for the diagnostics of the electron-beam relying on the fact that the emission spectrum of THz CSR depends on the shape of the electron bunch from which the radiation is emitted. Among available direct THz detectors only superconducting microbolometers and Schottky diodes are capable to resolve single CSR pulses. Here we present recent photoresponse measurements of CSR with a quasioptical zero-bias Schottky diode detector which was produced at ACST GmbH. The rise-time of the recorded real-time transient was limited to approximately 20 ps by the 18-GHz bandwidth of interconnecting cables. Non-saturated responsivity of the detector, that is the amplitude of the voltage transient referred to the total CSR pulse energy in the detector quasioptical mode, was approximately 1.5 mV/fJ. The dynamic range of the detector spans almost three orders of magnitude from 3 fJ to 1 pJ. The intrinsic jitter of the detector was less than 2 ps thus not affecting the effective time resolution and allowing us to measure the arrival-time jitter of CSR pulses for different settings of the storage ring parameters., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Ultrashort electron bunches are essential for time-resolved measurement methods such as pulse radiolysis* from the viewpoint of time resolutions. On the other hand, generation of electro-magnetic wave in the THz range using short electron bunches has been investigated**. Frequency spectra of coherent transition radiation (CTR) emitted by an electron bunch depend on bunch form factor (BFF), which is expressed by Fourier coefficients of longitudinal distribution in the electron bunch. In this study, the bunch length measurement was demonstrated by analyzing THz-waves generated by CTR. Femtosecond electron bunches were generated by a laser photocathode RF gun linac and magnetic bunch compressor. THz-waves generated by CTR, which was emitted on an interface of an aluminum mirror along the beam trajectory, were transported to a Michelson interferometer. The bunch length was measured by analyzing interferogram, which was an infrared detector output as a function of a moving mirror position. Finally, the bunch length was measured according to fitting curves for the interferogram near the centerburst***. Minimum bunch length of 1.3 fs was obtained at a bunch charge of ~1 pC., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Beam halo hitting on the beam pipe after the Interaction Point (IP) can generate a large amount of background for the measurements of the nano meter beam size using the laser interferometer beam size monitor (Shintake monitor) at ATF2. In order to investigate the beam halo transverse distribution, a diamond detector will be installed downstream of the IP. A feasibility study of a transverse halo collimation system to reduce the background for these measurements is also in progress. Prior to the diamond detector installation, a first attempt of beam halo measurements have been performed in 2013 using the currently installed wire scanners. Modeling of the beam halo distribution in the extraction (EXT) line was done and compared with the old modeling for ATF. Beam halo measurements were also done using the post-IP wire scanner to investigate the beam halo distribution at post-IP., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Pohang Accelerator Laboratory (PAL) built a PAL-ITF at the end of 2012 to successfully complete PAL-XFEL in 2015. The PAL-ITF is equipped with various kinds of diagnostic equipment to produce high-quality electron bunches. An ICT and a Turbo-ICT were installed in the PAL-ITF. A Faraday Cup is installed at the end of the linear accelerator. These days, the quantity of electric charge occasionally is measured using a BPM Sum value. This paper focuses on the processes and results of electric charge quantity measurements using ICT, Turbo-ICT, FC and BPM. The PAL-ITF is equipped with Stripline-BPM. It is important to find a way to minimize measurement errors that can appear in the process of installing or measuring the BPM. For this, PAL-ITF separately measured the BPM electrode sensitivity and minimized BPM measurement errors through generally calibrating BPM devices by applying Lambertson's Method. A plan was made to minimize BPM measurement errors through applying the BPM electrical calibration method for BPM devices to be used by the PAL-XFEL. This paper examines the processes for checking the performance of the S-BPM installed in the PAL-ITF and the results of its measurements., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Knowing the longitudinal phase space of an electron beam is one of the most important and crucial issues in short-pulses linacs. To achieve this task expensive and rather complicated setups (like transverse deflecting cavities) are usually implemented. The MAX IV 3 GeV linac will be used to inject into two rings and to drive a short pulse facility. Nevertheless, a more deep understanding of the beam quality would be useful especially in view of an upgrade as FEL driver. Another interesting aspect is to evaluate how the double-achromat bunch compressors are performing. We are studying how to implement off-phase acceleration: last part of the linac will be set at zero-crossing phase and the transfer line to the 3 GeV ring could be used as energy spectrometer to retrieve the bunch profile. In the present configuration of the MAX IV linac this procedure will allow to check the bunch length after the first bunch compressor. Since it is work in progress, in this contribution we present a sketch of the measurement and the feasibility of the method will be explored by means of simulations., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

At the Large Hadron Collider (LHC) at CERN, synchrotron radiation (SR) is used to continuously monitor the transverse properties of the beams. Unfortunately the machine and beam parameters are such that the useful radiation emitted inside a separation dipole, chosen as source, is diffraction limited affecting heavily the accuracy of the measurement. In order to deconvolve the diffraction effects from the acquired beam images and in order to design an alternative monitor based on a double slit interferometer an extensive study of the synchrotron light source and of the optical propagation has been made. This study is based on simulations combining together several existing tools: SRW for the source, ZEMAX for the transport and MATLAB for the "glue" and analysis of the results. The resulting tool is very powerful and can be easily adapted to other synchrotron radiation problems. In this paper the simulation package and the way it is used will be described as well as the results obtained for the LHC and SPS cases., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The cryogenic storage ring (CSR) at MPI für Kernphysik is an electrostatic storage ring for low velocity phase space cooled ion beams. Among other experiments cooling and storage of molecular ions in their rotational ground state is projected. The stored beam current will be in the range of 1 nA - 1 μA. The resulting low signal strengths on the beam position pickups, current monitors and Schottky monitor put strong demands on these diagnostics tools. Methods and systems were developed to measure the profile of the ion beam. In the paper a summary of the CSR diagnostics tools and diagnosis of the first stored ion beam will be given., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Sirius is a 3 GeV synchrotron light source that is being built by the Brazilian Synchrotron Light Laboratory (LNLS). It will be part of a novel class of light sources with emittances in the sub-nm level. Both horizontal and vertical beam sizes at the dipoles will be of the order of or below 10μm, creating difficulties for measuring them using conventional techniques. This paper proposes a series of beamlines using different techniques that, combined, will be able not only to resolve beam sizes, but also measure energy spread and local transverse coupling in the storage ring., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

We report about the design of a spectrometer for energy spectrum measurements of an electron beam generated by a superconducting radio-frequency photoelectron gun (SRF gun), which is under construction at HZB for BERLinPro. The spectrometer shall provide absolute accuracy of energy measurements of about 0.1% and energy resolution about 0.1%. The spectrometer will be also used for single shot phase space measurements in combination with a transverse deflecting cavity., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The ability to use a radiation of relativistic electrons in optical fibers for beam diagnostics was proposed by X. Artu recently *. In the cited work the properties of different types of radiation, such as diffraction and Cherenkov radiation in the visible region, induced in fibers by relativistic electron were considered. In our report we present the results of experimental investigation of such a phenomenon for millimeter wavelength radiation. The origin and properties of radiation in fibers were investigated for different geometries of fiber position in respect to the electron beam. The spectral characteristics and dependence on the orientation angle of fibers relative to the electron beam were investigated. One of the useful properties of fibers is the fiber flexibility. The characteristics of radiation accepted by flexible fiber with diameter D=11 mm and length L=600 mm were investigated as a function of curvature radius of the fiber R. The experimental results show the allowable transport factor of radiation for the condition L>R>>D. We believe that fibers for mm and submm range can be used for beam diagnostics also., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. Its 50 Hz, 800 MeV proton synchrotron delivers a mean beam power of 0.2 MW to two spallation targets. Recent developments to beam control and measurement systems at ISIS are described. New PXI-based digitising hardware and custom software developed with LabVIEW have increased the capability to study beam behaviour. New, more flexible power supplies for steering and trim quadrupole correction magnets have been commissioned allowing greater control of beam orbits and envelopes. This paper looks at recent linear lattice measurements and attempts to identify the source of lattice errors., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

For the pulse charge q injected into a capacitor of a parallel resonating circuit, the oscillation voltage V on a series resistor R is V=qwRexp(—wt/2Q)sin(wt–1/2Q), t>τ, where w is the resonance frequency, Q>>1 is the quality factor and τ<, Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

A new beam intensity measurement (BIM) system has been developed and has been used in the upgrade project of HLS II. After the upgrading is accomplished, electron energy in Injector endpoint will increase from 200MeV to 800MeV to achieve the goal of top-off injector. Meanwhile, macro pulse width changes from 1us to 1ns and peak intensity from 50mA to 1A approximately. So three fast current transformers (FCTs) and two integrating current transformer (ICTs) are installed in Linac and Transport Line to measure single pass beam parameters. In this article, off-line calibration of beam transformer is elaborated. Since the fast pulse signals from beam transformer will be hugely distorted after they transmit from Injector vacuum chamber to the Injector beam diagnostic centre room after hundreds of meters long LMR-400 cable, signal recovery algorithm based on FFT/IFFT is used to re-appear the true original signal and calculate the calibration efficient. In the end, resolution and measurement result of the BIM system is presented., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Orbit stability in 100 nm range is essential for a very small emittance synchrotron light source. However, all kinds of vibration source such as cultural noise and technical noise might deleterious the orbit stability. A synchronous data acquisition system is promising to study connection of orbit motion and various vibration related sources. In this report, we present a synchronous data acquisition system which integrates the measurement of beam position and vibration and then this system will deploy for the Taiwan Photon Source (TPS). To test the applicability of the system, systematic study orbit motion caused by vibration using this system was performed at Taiwan Light Source (TLS). Preliminary results will summary in this report., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

MedAustron is a synchrotron based accelerator complex, used for cancer treatment as well as for non-clinical research, and is situated in Wiener Neustadt, Austria. Cosylab has been working closely with MedAustron to develop the core accelerator control system and is now also working on on-site integration of beam diagnostics (BD) devices. These devices are critical for commissioning of the accelerator as well as later during regular operation to ensure high up-time of the machine. Beam instrumentation devices are fully integrated into the Front End Controller Operating System (FECOS) of the accelerator. FECOS is a custom designed control system framework implemented in LabVIEW, which provides unified interfaces and core services to all software components in the system. The Master Timing System component provides configurable real-time events distribution (triggers), essential for measurement and control in sections where the beam is bunched and device actions need to be synchronized. Both companies, MedAustron and Cosylab also developed user interfaces that are designed to be intuitive, while maintaining a level of flexibility for physics research., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

An ultra high position resolution cavity BPM was developed for the final focus system of ATF2, which is a accelerator test facility for ILC final focus system. The main purpose of ATF2 are achievement of 37 nm beam size and nano-meter beam orbit stability at IP(Interaction Point). For these purposes, a few nano meter beam position resolution was required for this cavity BPM, which is called the IP-BPM. The IP-BPM was fabricated 2 blocks of IP-BPM, the first block consists of two cavities in one block and second block consists of single cavity. IP-BPM can measure beam position in vertical and horizontal independently by using rectangular shape single cavity. Three IP-BPMs were installed at ATF IP region inside IP-chamber, and its position resolution was measured. We will present the detailed results on the beam tests., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

One of the most important parameters of accelerators is their beam energy. So far, the method of resonant depolarization was used to accurately determine the energy at 2.5 GeV of the ANKA electron storage ring, which, however, becomes cumbersome for lower energies. A good alternative is the detection of Compton backscattered photons, generated by laser light scattered off the relativistic electron beam. To achieve compactness and integration into the storage ring, the setup of transverse scattering is proposed instead of conventional head-on collision. The feasibility has been studied by comparison between simulations of Compton backscattered photons by AT and CAIN 2.35 and actual measurement of background radiation with an HPGe (High Purity Germanium) spectrometer. The layout of the setup is also included in the paper., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

At the ALBA synchrotron light source, the filling pattern is measured using a Fast Current Transformer (FCT). Applying a data analysis the filling pattern is measured with a dynamic range in the order of 10², limited by the electronic noise in the device. A new experimental set-up for filling pattern measurements was implemented using the Time Correlated Single Photon Counting. The technique consists in the measurements of the temporal distribution of the produced synchrotron radiation using Electro-Optical devices, from where the filling pattern is inferred. Two different photomultipliers are used to perform the measurement and results are compared. A further comparison between results from the photomultipliers and the FCT is performed to verify the accuracy of the results., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

A new beam diagnostics system was developed and built at the Siemens Healthcare Sector facility in Rudolstadt, Germany. The project goal was to develop, commission and operate a complete beam diagnostics system to fully characterize the compact medical linear electron accelerators. An overview of the whole system including the beam diagnostics, linear accelerator and control and supply unit is given. The system was successfully commissioned in July 2013. We report on initial experiences and first experimental results on current measurements, transverse beam size, transverse emittance and momentum and momentum distribution gained during the commissioning phase., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Cherenkov radiation is a convenient tool for charged particle detection and bunch diagnostics. However, due to the complexity of real radiator geometry, different approximate techniques are elaborated for investigation of excited radiation*. Here we develop recently reported** approximate method for calculating Cherenkov radiation of a charge flying near a dielectric target having two main boundaries (the first interacts with a charge field and the second mainly refracts a generated radiation). We focus on cases where the radiation outside the target is convergent and use two methods for field investigation: ray optical technique and aperture integration technique. First, we deal with the case of a conical target with a vacuum channel. Under certain conditions, this radiation is concentrated near the line being the symmetry axis of the target. Second, we find the specific shape of the target that concentrates radiation in a small vicinity of given point (focus). Such targets can be used for improvement of detectors and bunch diagnostics systems based on Cherenkov effect., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The FAIR (Facility for Antiproton and Ion Research) accelerator facility presently under construction at GSI will supply a wide range of beam intensities for physics experiments. Design beam intensities range from 2.5·10¹³ protons/cycle to be delivered to the pBar-target and separator for production of antiprotons, to beams of e.g. 10⁹ ions/s in the case of slowly extracted beams. The large intensity range demands for dedicated beam current monitors for precise, non-destructive beam intensity measurements in the synchrotrons, transport lines and storage rings of the FAIR facility. This report describes GSI developments of purpose-built beam current monitors for the SIS100 synchrotron and high-energy beam transport lines (HEBT) of FAIR. Prototype measurements with a SQUID-based Cryogenic Current Comparator and a resonant beam charge transformer are presented, and possibilities for further upgrades are discussed., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Design of the Beam Profile Monitors for THz Source Based FEL* J. Liu, P. Lu, B. G. Sun#, Y. J. Pei, Y. L. Yang, Z.R. Zhou, J. G. Wang, K. Tang, J. Xu NSRL, School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230029, P. R. China Abstract To meet requirements of high performance THz-FEL, a compact FEL facility was proposed. In order to characterize the beam, some beam profile monitors were designed. There are four flags for beam profiles in Linac，one pop-in monitor for high precision beam profile inside a small-gap undulator, and two screens to measure the beam energy spread and emittance of Linac. On one hand, we need to use software to control the position of these profile monitors, on the other hand, we need screens to display the results. This paper describes how to design and control these monitors, as well as how to measure the beam parameter., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Super luminous flavor factories, as SuperKEKB in Japan, aim to achieve very high luminosity thanks to a newly employed concept, the nano-beam scheme, where ultra-low emittance beams collide at very large crossing angle . Luminosity optimisation and dynamic imperfections require fast luminosity measurements. The aimed precision, 10⁻³ in 10 ms, can be achieved thanks to the very large cross-section of the radiative Bhabha process at zero-photon scattering angle. As a result of huge particle fluxes, diamond sensors are chosen to be placed just outside the beam-pipe, downstream of the interaction point, at locations with event rates consistent with the aimed precision and small enough contamination by backgrounds from single-beam particle losses . We will present the results concerning the investigation of the optimal positioning of our diamond sensors, taking into account the rate of Bhabha particles, their interactions with the beam pipe material., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The linear avalanche photodiodes array is applied for turn-to-turn beam profile measurement at Siberia-2 synchrotron light source. The apparatus is able to record a transversal profile of selected bunch and analyze the dynamics of beam during 2²⁰ turns. The first experience with application of new diagnostics for routine use at the installation is described., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Principal component analysis is a powerful data analysis tool, capable of reducing large complex data sets containing many variables. Examination of the principal components set allows the user to spot underlying trends and patterns that might otherwise be masked in a very large volume of data, or hidden in noise. Diamond Light Source archives many gigabytes of machine data every day, far more than any one human could effectively search through for correlations. Presented in this paper are some of the results from running principal component analysis on years of archived data in order to find underlying correlations that may otherwise have gone unnoticed. The advantages and limitations of the technique are discussed., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Non–invasive, highly accurate and reliable beam monitors are a desired aim of any beam diagnostics design. Knowledge of beam parameters is essential in fundamental research, industry or medical applications with varying demands. It is critical for the optimization of ion beams used for cancer treatment. Ocular tumor treatment at the Clatterbridge Cancer Center (CCC) uses a 60 MeV proton beam. Disturbances introduced to a beam by intercepting devices risk affecting its energy and energy spread, thereby limiting its effectiveness for treatment. The advantageous semi-circular structure of the LHCb Vertex Locator (VELO) detector has been investigated in the QUASAR Group. It is an interesting option for a non-invasive online beam monitor relying on beam ‘halo’ measurements without disturbing the part of the beam used for treatment. This contribution discusses the measurement method, setup design and integration within the CCC treatment beam line., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

At the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University as a synchrotron radiation user facility, bunch-by-bunch feedback systems are in use for electron beam diagnostics and for the suppression of multibunch instabilities. An automatic readout of bunch position data allows a real-time modal analysis during machine operation. An excitation of particular multibunch modes enables the determination of growth and damping times for all modes independently. Further investigations of beam stability and natural damping times of all modes even below the instability threshold have been performed. In addition, first bunch-by-bunch data taken from the booster synchrotron are shown., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany