IBIC2013 - List of Keywords (synchrotron)

Paper	Title	Other Keywords	Page
MOPC20	Application of Metal-Semiconductor-Metal (MSM) Photodetectors for Transverse and Longitudinal Intra-Bunch Beam Diagnostics	BPM, CTF3, CERN, diagnostics	97
	R.J. Steinhagen CERN, Geneva, Switzerland M.J. Boland SLSA, Clayton, Australia T.G. Lucas, R.P. Rassool The University of Melbourne, Melbourne, Australia T.M. Mitsuhashi KEK, Ibaraki, Japan
	The performance reach of modern accelerators is often governed by the ability to reliably measure and control the beam stability. In high-brightness lepton and high-energy hadron accelerators the use of optical diagnostic techniques for this purpose is becoming more widespread as the required bandwidth, resolution and high RF beam power level involved limit the use of traditional electro-magnetic RF pick-up based methods. This contribution discusses the use of fibre-coupled ultra-fast Metal-Semiconductor-Metal Photodetectors (MSM-PD) as an alternative, dependable means to measure signals deriving from electro-optical and synchrotron-light based diagnostics systems. It describes the beam studies performed at CERN's CLIC Test Facility (CTF3) and the Australian Synchrotron to assess the feasibility of this technology as a robust, wide-band and sensitive technique for measuring transverse intra-bunch and bunch-by-bunch beam oscillations, longitudinal beam profiles, un-bunched beam population and beam-halo profiles. The used amplification schemes, achieved sensitivities, linearity, and dynamic range of the detector setup are presented.
	Poster MOPC20 [3.065 MB]

MOPC31	Streak Camera Imaging at ELSA	ELSA, feedback, longitudinal, transverse	132
	M.T. Switka, W. Hillert, M. Schedler, S. Zander ELSA, Bonn, Germany
	Funding: Funded by the DFG within SFB/TR 16 The Electron Stretcher Facility ELSA provides polarized electrons with energies up to 3.2 GeV for external hadron experiments. In order to suffice the need of stored beam currents towards 200 mA, studies of instabilities and the effect of adequate countermeasures are essential for appropriate machine settings. For this purpose a new diagnostic beamline has been constructed. It is optimized for transverse and longitudinal streak camera measurements with time resolution down to one picosecond. Operation of the diagnostic beamline has recently started and first measurements are presented.

MOPC35	A Beam-Synchronous Gated Peak-Detector for the LHC Beam Observation System	LHC, CERN, longitudinal, injection	147
	T.E. Levens, T. Bohl, U. Wehrle CERN, Geneva, Switzerland
	Measurements of the bunch peak amplitude using the longitudinal wideband wall-current monitor are a vital tool used in the Large Hadron Collider (LHC) beam observation system. These peak-detected measurements can be used to diagnose bunch shape oscillations, for example coherent quadrupole oscillations, that occur at injection and during beam manipulations. Peak-detected Schottky diagnostics can also be used to obtain the synchrotron frequency distribution and other parameters from a bunched beam under stable conditions. For the LHC a beam-synchronous gated peak detector has been developed to allow individual bunches to be monitored without the influence of other bunches circulating in the machine. The requirement for the observation of both low intensity pilot bunches and high intensity bunches for physics requires a detector front-end with a high bandwidth and a large dynamic range while the usage for Schottky measurements requires low noise electronics. This paper will present the design of this detector system as well as initial results obtained during the 2012-2013 LHC run.
	Poster MOPC35 [2.792 MB]

MOPC39	Commissioning of a New Streak Camera at TLS for TPS Project	laser, storage-ring, longitudinal, feedback	159
	C.Y. Liao, M.C. Chou, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-C. Kuo, W.K. Lau, C.Y. Wu NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) is a 3 GeV synchrotron light source which is being construction at campus of National Synchrotron Radiation Research Center (NSRRC) in Taiwan. A new streak camera equipped with a 125/250 MHz synchroscan unit, a fast/slow single sweep unit, and a dual-time sweep unit is prepared for beam diagnostics, especially for the TPS. An ultra short femtosecond Ti-Sapphire laser was used to evaluate the sub-picosecond temporal resolution of the streak camera and the first beam measurements of the streak camera using synchrotron light from the existing 1.5 GeV Taiwan Light Source (TLS) were performed. The commissioning results are summarized in this report.

MOPF01	Transverse Beam Size Measurements Using Interferometry at ALBA	vacuum, transverse, dipole, radiation	193
	U. Iriso, L. Torino CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain T.M. Mitsuhashi KEK, Ibaraki, Japan
	Double-slit interferometry using visible light has been used for measuring the transverse beam size in different accelerators. The beam size is inferred from the analysis of the spatial coherence of the synchrotron light produced by a bending magnet. At ALBA, this technique has been implemented with moderate success, mainly limited by the present imperfections in the in-vacuum mirror that is used to extract the light out of the vacuum chamber. In this paper, we report the results obtained with the current set-up, and discuss possible improvements.

MOPF19	Injection Efficiency Monitoring System at the Australian Synchrotron	injection, booster, extraction, background	248
	E.D. van Garderen, S.A. Griffiths, G. LeBlanc, S. Murphy, A. Rhyder, A. C. Starritt ASCo, Clayton, Victoria, Australia M.J. Boland SLSA, Clayton, Australia
	The Australian Synchrotron upgraded its user mode from decay mode to top-up mode in May 2012. To monitor the beam charge passing through the accelerator systems at key transfer points the transmission efficiency system has been upgraded. The original system could only measure the efficiency of the booster to storage ring injection. The new one calculates intermediate efficiencies between six points along the injection system, from the electron gun to the booster-to-storage ring transfer line. This is helpful to diagnose in real-time shot-to-shot the performance of the pulsed magnets, ramped magnets and ramped RF systems and their associated triggers. A software-based injection efficiency interlock has also been introduced, that can inhibit the gun when the machine settings are not optimal. This article details the architecture of the injection efficiency system and lists the improvements on the machine that have been carried out to obtain high quality data.

MOPF20	Bunch Purity Measurement for BEPCII	photon, synchrotron-radiation, radiation, electron	252
	H. Jun, J.S. Cao, J.H. Junhui IHEP, Beijing, People's Republic of China
	The bunch purity is very important for time-resolved experiments. It is determined by the quality of the injection system and Touschek effect. The Beijing Electron-Positron Collider (BEPC) II was constructed for both high energy physics (HEP) and synchrotron radiation (SR) researches. It can be operated in the colliding mode and synchrotron radiation mode. It is planned to measure the beam quality in a short time of several minutes by using a timecorrelated single photon counting method. The method has a time resolution of 450 ps and a dynamic range of five orders of magnitude. In this paper, we describe our experimental set up and give a series of test results for colliding mode. We plan to set up a system which can kick out the unwanted bunches in the next stage.

MOPF26	New Booster Tune Measurement System for TLS and TPS Prototype	booster, kicker, BPM, beam-losses	271
	P.C. Chiu, J. Chen, Y.-S. Cheng, K.T. Hsu, S.Y. Hsu, K.H. Hu, C.H. Kuo NSRRC, Hsinchu, Taiwan
	Taiwan Light Source (TLS) is a 1.5 GeV synchrotron based light source and its booster synchrotron was delivered in 1992. Initial booster tune measurement which adopted extraction kicker as beam excitation and use digital oscillator to extract tune was obsolete. Recently, the beam excitation device has been modified to provide more effective excitation strength and new BPM electronics is adopted to acquire tune for routine booster tune measurement. It also provides a chance to experience for the TPS project booster prototype with the similar infrastructure. Efforts will be summarized in the report.

MOPF28	Optics Non-Linear Components Measurement Using BPM Signals	optics, focusing, BPM, beam-losses	279
	M. Alhumaidi, A.M. Zoubir TU Darmstadt, Darmstadt, Germany
	The knowledge of linear and non-linear errors in circular accelerator optics is very crucial for controlling and compensating resonances and their consequent beam losses. This is indispensable, especially for high intensity machines. Fortunately, the relationship between the recorded beam offset signals at the BPMs is a manifestation of the accelerator optics, and can therefore be exploited in the determination of the optics linear and non-linear components. We propose a novel method for estimating lattice non-linear components located in-between the positions of two BPMs by analyzing the beam offset signals of a BPMs triple containing these two BPMs. Depending on the non-linear components in-between the locations of the BPMs triple, the relationship between the beam offsets follows a multivariate polynomial. After calculating the covariance matrix of the polynomial terms, the Generalized Total Least Squares method is used to find the model parameters, and thus the non-linear components. Finally, a bootstrap technique is used to determine confidence intervals of the estimated values. Results for synthetic data are shown.

MOPF34	Nuclotron Deuterons Beam Parameters Measurements Using SSNTD	target, dipole, vacuum, quadrupole	299
	K.V. Husak, V.V. Bukhal The Joint Institute of Power and Nuclear Reserach - "SOSNY" NASB, Minsk, Belarus M. Artiushenko, V.V. Sotnikov, V.A. Voronko NSC/KIPT, Kharkov, Ukraine A.A. Patapenka, A.A. Safronava, I.V. Zhuk JIPNR-Sosny NASB, Minsk, Belarus
	ADS are considered as prospective nuclear installations for energy production and nuclear waste transmutation or recycling. The international project “Energy and Transmutation Radioactive Wastes” running in the Laboratory of High Energy Physics at JINR (Dubna, Russia) at the accelerator complex “Nuclotron” is aimed at a feasibility study of using a deeply subcritical natural or depleted uranium or thorium active core with very hard neutron spectrum inside for effective burning of the core material together with spent nuclear fuel. For any ADS experiment a necessary and a key element is beam diagnostics. In this paper a technique for precise measurement of deuteron beam parameters using SSNTD, developed within the bounds of “E&T RAW” project, is presented. The deuteron beam parameters, specifically beam shape, size and position on a target, are obtained from track density distribution on the irradiated track detectors. The presented technique has a resolution of 1 mm. The experimental results of beam parameter measurements for deuterons with energies of 2, 4 and 8 GeV at the irradiation of the uranium subcritical assembly “QUINTA”, obtained with the SSNTD technique, are presented.
	Poster MOPF34 [0.826 MB]

TUBL3	A Multiband-Instability-Monitor for High-Frequency Intra-Bunch Beam Diagnostics	LHC, CERN, SPS, pick-up	327
	R.J. Steinhagen CERN, Geneva, Switzerland M.J. Boland, T.G. Lucas The University of Melbourne, Melbourne, Australia
	To provide the best possible luminosity, even higher beam intensities are needed in the Large Hadron Collider (LHC) and in its injector chain. This is fundamentally limited by self-amplifying beam instabilities, intrinsic to unavoidable imperfections in accelerators. Traditionally, intra-bunch or head-tail particle motion is measured using fast digitizers, which even using state-of-the-art technology are limited in their effective intra-bunch position resolution to few tens of um in the multi-GHz regime. Oscillations at this scale cause partial or total loss of the beam due to the tight transverse constraints imposed by the LHC collimation system. To improve on the present signal processing, a prototype system has been designed, constructed and tested at the CERN Super-Proton-Synchrotron (SPS) and later on LHC. The system splits the signal into multiple equally-spaced narrow frequency bands that are processed and analysed in parallel. Working with narrow-band signals in frequency-domain permits the use of much higher resolution analogue-to-digital-converters that can be used to resolve nm-scale particle motion already during the onset of instabilities.
	Slides TUBL3 [3.165 MB]

TUPC08	Design and Impedance Optimization of the LNLS-UVX Longitudinal Kicker Cavity	longitudinal, kicker, impedance, feedback	369
	L. Sanfelici, H.O.C. Duarte, S.R. Marques LNLS, Campinas, Brazil
	Performance evolution of parameters achieved during the electromagnetic design of the longitudinal kicker cavity for the LNLS UVX storage ring is presented. The effort on the electromagnetic optimization process of the heavily loaded cavity has been made to reach the required electrodynamic parameters of the kicker. The results for three different geometries are compared and a good compromise between the longitudinal shunt impedance and the effect of the longitudinal Higher Order Modes (HOM’s) on beam stability has been found.
	Poster TUPC08 [1.365 MB]

TUPC10	Operation of Diamond Light Source XBPMs with Zero Bias	electron, DIAMOND, photon, beam-position	376
	C. Bloomer, G. Rehm Diamond, Oxfordshire, United Kingdom
	Tungsten blade X-ray Beam Position Monitors (XBPMs) have been used at Diamond Light Source since 2007, however a long-standing problem with these devices has been the growth of leakage current through the ceramic insulation within the XBPMs over time, often becoming greater than 10% of the signal current after a few years of operation. The growth of these leakage currents has been found to be exacerbated by the application of a negative bias (-70V) to the tungsten blades, a bias suggested for optimum position sensitivity. This bias is applied in order to accelerate free electrons away from the surface of the blades and to prevent cross-talk, however, we have found that the operation of the XBPMs without bias has negligible impact on our measurements. Removal of the bias has been found to prevent the growth of leakage currents over time, and can also significantly reduce the cost of our signal acquisition by removing the need for a low-current amplifier with a bias supply.
	Poster TUPC10 [0.455 MB]

TUPC18	Development of a Highly Efficient Energy Kicker for Longitudinal Bunch-by-Bunch Feedback	kicker, longitudinal, electron, storage-ring	407
	M. Masaki, T. Fujita, K. Kobayashi, T. Nakamura, H. Ohkuma, M. Oishi, S. Sasaki, M. Shoji JASRI/SPring-8, Hyogo-ken, Japan
	A highly efficient energy kicker has been developed for longitudinal bunch-by-bunch feedback to suppress synchrotron oscillation of a high-current single electron bunch, and to cure possible longitudinal multi-bunch instability if lower beam energy is to be adopted for emittance reduction and electric power saving in a future upgrade plan of SPring-8. Through the performance test using a prototype kicker, a new water-cooled copper kicker was designed and fabricated, and it has been installed in the storage ring. The new kicker consists of three cells with each cavity length of 96 mm, its resonant frequency of 1.65 GHz, which is 3.25 times of RF frequency of the storage ring, and low Q-factor of 4.2. In beam kick test, the synchrotron oscillation amplitude of 0.64 ps was excited by kick voltage with continuous amplitude modulation at synchrotron frequency when the RF input power was 132 W/3cells. The kick voltage evaluated from the experimental result is 920 V/3cells. Shunt impedance of each kicker cell is estimated as 1.1 kΩ. As we intended, the shunt impedance per length is about three times higher than those of widely used waveguide overloaded cavity type kickers.
	Poster TUPC18 [9.117 MB]

TUPC43	Bunch Length Measurement With Streak Camera At SSRF Storage Ring	electron, longitudinal, storage-ring, diagnostics	478
	J. Chen, Z.C. Chen, Y.B. Leng, K.R. Ye, R.X. Yuan SINAP, Shanghai, People's Republic of China
	A streak camera is installed to measure the bunch length of storage ring at SSRF. The principle, structure, configuration and error analysis of the measurement is introduced. Some result of the measurement are analysed to explain the physical meaning of beam status. The system is used in daily operation and machine study at SSRF.

TUPF03	Performance Assessment of Wire-Scanners at CERN	LHC, SPS, CERN, laser	499
	G. Baud, B. Dehning, J. Emery, J-J. Gras, A. Guerrero, E.P. Piselli CERN, Geneva, Switzerland
	This article describes the current fast wire-scanner devices installed in circular accelerators at CERN with an emphasis of the error studies carried out during the last two runs. At present the wire-scanners have similar acquisition systems but are varied in terms of mechanics. Several measurement campaigns were performed aimed at establishing optimal operational settings and to identify and assess systematic errors. In several cases the results led to direct performance improvements while in others this helped in defining the requirements for new detectors.
	Poster TUPF03 [1.040 MB]

TUPF20	Low Noise and High Dynamic Range Optical Interferometer Beamsize Measurements	emittance, coupling, storage-ring, background	550
	M.J. Boland SLSA, Clayton, Australia T.M. Mitsuhashi KEK, Ibaraki, Japan K.P. Wootton The University of Melbourne, Melbourne, Australia
	The technique of optical interferometry to measure beam sizes requires a low noise and high dynamic range digitisation system to push the performance to ultra low emittance on storage rings. The next generation of camera sensor Scientific CMOS (sCMOS) promises to provide the technology to improve optical interferometry. A series of measurements was performed on the Australian Synchrotron storage ring using a sCMOS and a intensity imbalance optical interferometer. The coupling in the storage ring was varied from maximum to minimum using the skew quadrupoles and the beam size at the optical diagnostic beamline was varied from over 100 microns to around 1 micron. A comparison is made between interferometer measurements using the sCMOS with and without an intensity imbalance and with previous measurements using a CCD system.

TUPF28	A Leading-Edge Hardware Family for Diagnostics Applications and Low-Level RF in CERN’s ELENA Ring	CERN, controls, antiproton, diagnostics	575
	M.E. Angoletta, A. Blas, M. Jaussi, P.M. Leinonen, T.E. Levens, J.C. Molendijk, J. Sanchez-Quesada, J. Simonin CERN, Geneva, Switzerland
	The CERN Extra Low ENergy Antiproton (ELENA) Ring is a new synchrotron that will be commissioned in 2016 to further decelerate the antiprotons transferred from the CERN’s Antiproton Decelerator (AD). The requirements for the acquisition and treatment of signals for longitudinal diagnostics are very demanding, owing to the revolution frequency swing as well as to the digital signal processing required. The requirements for the Low-Level RF (LLRF) system are very demanding as well, especially in terms of revolution frequency swing, dynamic range and low noise required by the cavity voltage control and digital signal processing to be performed. Both sets of requirements will be satisfied by using a leading-edge hardware family, developed to cover the LLRF needs of all synchrotrons in the Meyrin site; it will be first deployed in 2014 in the CERN’s PSB and in the medical machine MedAustron. This paper gives an overview of the main building blocks of the hardware family and of the associated firmware and IP cores. The performance of some blocks will also be detailed.

WECL3	The LUPIN Detector: Supporting Least Intrusive Beam Monitoring Technique Through Neutron Detection	radiation, beam-losses, monitoring, proton	648
	G.P. Manessi, M. Silari CERN, Geneva, Switzerland M. Caresana Politecnico/Milano, Milano, Italy M. Ferrarini CNAO Foundation, Milan, Italy G.P. Manessi, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom G.P. Manessi, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	The Long interval, Ultra-wide dynamic Pile-up free Neutron rem counter (LUPIN) is a novel detector initially developed for radiation protection purposes, specifically conceived for applications in pulsed neutron fields. The detector has a measurement capability varying over many orders of neutron burst intensity, from a single neutron up to thousands of interactions for each burst, without showing any saturation effect. Whilst LUPIN has been developed for applications in the radiation protection fields, its unique properties make it also well suited to support other beam instrumentation. In this contribution, the design of LUPIN is presented in detail and its main characteristics are summarized. Its potential use as beam loss monitor and complementary detector for non-invasive beam monitoring purposes (e.g. to complement a monitor based on proton beam “halo” detection) in medical accelerators is then examined. In the context of its application as a beam loss monitor for hadrontherapy accelerators, results of measurements performed at the Italian National Centre of Hadrontherapy (CNAO) are presented and analyzed.
	Slides WECL3 [1.431 MB]

WEPC34	Time Trend Observation of Certain Remarked Bunches using a Streak Camera	longitudinal, injection, damping, KEK	761
	T. Naito, S. Araki, H. Hayano, K. Kubo, S. Kuroda, T.M. Mitsuhashi, T. Okugi, S. Sakanaka, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan
	Funding: This work is supported by Japan-U.S. cooperative program . A streak camera with two dimensional sweep function can measure the trend of the longitudinal beam profile in the ring. In the case of the multi-bunch measurement, the different bunch profile sit on same timing, thus, we can not distinguish the behavior of each bunch. We have developed a trigger circuit to measure the bunch-by-bunch longitudinal beam profile, which uses non integer sweep frequency for the acceleration frequency. The bunch profile of each bunch sit on different position in this measurement. We observed the increment of the synchrotron oscillation amplitude from the first bunch to the 20th bunch in the KEK-ATF Damping Ring by using this system. This paper describes the hardware and the measurement results.

WEPC36	Development of Electron Bunch Compression Monitors for SwissFEL	electron, radiation, longitudinal, transverse	769
	F. Frei, B. Beutner, I. Gorgisyan, R. Ischebeck, G.L. Orlandi, P. Peier, E. Prat, V. Schlott, B. Smit PSI, Villigen PSI, Switzerland P. Peier DESY, Hamburg, Germany
	SwissFEL will be a hard x-ray fourth generation light source to be built at Paul Scherrer Institut (PSI), Switzerland. In SwissFEL the electron bunches will be produced with a length of 3ps and will then be compressed by a factor of more than 1000 down to a few fs in order to generate ultra short x-ray pulses. Therefore reliable, accurate and noninvasive longitudinal diagnostic is essential after each compressing stage. In order to meet the requirements of this machine, new monitors have to be developed. We will present recent results of setups that measure electro-magnetic radiation, namely edge, synchrotron and diffraction radiation, emitted by the electron bunches (far field, spectral domain). These monitors are tested in the SwissFEL Injector Test Facility. A state of the art S-band Transverse Deflecting Cavity together with a Screen Monitor is used for calibration.

WEPC39	First Tests of the Top-up Gating at Synchrotron SOLEIL	injection, SOLEIL, storage-ring, kicker	775
	J.P. Ricaud, L. Cassinari, P. Dumas, P. Lebasque, A. Nadji SOLEIL, Gif-sur-Yvette, France
	Since 2006, Synchrotron SOLEIL is delivering photons to its beamlines. Until 2012, thanks to the excellent performances of the injection system of the storage ring, the perturbation on the position of the stored beam was small enough to be accepted by the users. For some specific experiments, few beamlines expressed their wish to be able to stop their data acquisition during the injection. To fulfill this need, the diagnostics group of Synchrotron SOLEIL has designed the “TimEX3” board which was integrated into the timing system allowing the gating of the Top-up injection. This design was released as open hardware. Towards this aim, we decided to design it with the open source and free EDA software “KiCad”, and to make it available under the CERN’s Open Hardware Repository.
	Poster WEPC39 [0.521 MB]

WEPF31	A FESA DAQ for Fast Current Transformer in SIS 18	longitudinal, CERN, SIS, pick-up	894
	O. Chorniy, H. Bräuning, T. Hoffmann, H. Reeg, A. Reiter GSI, Darmstadt, Germany
	This contribution presents the development of the data acquisition (DAQ) system for the readout of fast beam current transformers (FCT) as installed in the GSI synchrotron SIS18 and as foreseen in several FAIR ring accelerators. Fast current transformers are reliable devices that offer a large analogue bandwidth and can therefore monitor bunch structures with high resolution. At appropriate sampling rates continuous measurements throughout repeated machine cycles lead to a large amount of raw data. The analysis of those raw data may range from simple bunch parameter calculations to complex longitudinal phase space reconstructions. Consequently, a new DAQ system must be carefully designed to allow for flexible acquisition modes or to allow for data reduction methods in special applications. The aims of the development are discussed and the status of the new DAQ is presented.
	Poster WEPF31 [2.307 MB]

WEPF34	Accurate Measurement of Small Electron Beam Currents at the MLS Electron Storage Ring	electron, storage-ring, synchrotron-radiation, radiation	903
	R. Klein, G. Brandt, D. Herzog, R. Thornagel PTB, Berlin, Germany
	The PTB, the German metrology institute, utilizes the electron storage ring MLS in Berlin Adlershof for the realization of the radiometric units in ultraviolet and vacuum ultraviolet spectral range. For this purpose the MLS can be operated as a primary source standard of calculable synchrotron radiation with very flexible parameters, especially in terms of electron beam energy and electron beam current. We report on improvements in the measurement of the electron beam current in the nA and pA range. In this range the electron beam current can be very accurately measured by counting the stored electrons.

THAL3	Charge Distribution Measurements at ALBA	photon, electron, BPM, injection	925
	L. Torino, U. Iriso CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	Two different set-ups are used to perform quantitative measurements of the charge distribution at ALBA. The first consists in a real-time analysis of data coming from the Fast Current Transformer or from the buttons of a Beam Position Monitor installed in the Storage Ring. The second is performed at the diagnostic visible beamline Xanadu, using a Photomultiplier that measures the temporal distribution of synchrotron light. In both cases a quantitative estimation of the charge distribution is obtained after a dedicated data treatment and beam current measurements from the DCCT. We compare results with both methods, and discuss differences and limitations with respect to bunch purity measurements with the Time Correlated Single Photon Counting technique.
	Slides THAL3 [15.369 MB]

Paper

Title

Other Keywords

Page

Application of Metal-Semiconductor-Metal (MSM) Photodetectors for Transverse and Longitudinal Intra-Bunch Beam Diagnostics

BPM, CTF3, CERN, diagnostics

97

R.J. Steinhagen
CERN, Geneva, Switzerland
M.J. Boland
SLSA, Clayton, Australia
T.G. Lucas, R.P. Rassool
The University of Melbourne, Melbourne, Australia
T.M. Mitsuhashi
KEK, Ibaraki, Japan

The performance reach of modern accelerators is often governed by the ability to reliably measure and control the beam stability. In high-brightness lepton and high-energy hadron accelerators the use of optical diagnostic techniques for this purpose is becoming more widespread as the required bandwidth, resolution and high RF beam power level involved limit the use of traditional electro-magnetic RF pick-up based methods. This contribution discusses the use of fibre-coupled ultra-fast Metal-Semiconductor-Metal Photodetectors (MSM-PD) as an alternative, dependable means to measure signals deriving from electro-optical and synchrotron-light based diagnostics systems. It describes the beam studies performed at CERN's CLIC Test Facility (CTF3) and the Australian Synchrotron to assess the feasibility of this technology as a robust, wide-band and sensitive technique for measuring transverse intra-bunch and bunch-by-bunch beam oscillations, longitudinal beam profiles, un-bunched beam population and beam-halo profiles. The used amplification schemes, achieved sensitivities, linearity, and dynamic range of the detector setup are presented.

Poster MOPC20 [3.065 MB]

MOPC31

Streak Camera Imaging at ELSA

ELSA, feedback, longitudinal, transverse

132

M.T. Switka, W. Hillert, M. Schedler, S. Zander
ELSA, Bonn, Germany

Funding: Funded by the DFG within SFB/TR 16
The Electron Stretcher Facility ELSA provides polarized electrons with energies up to 3.2 GeV for external hadron experiments. In order to suffice the need of stored beam currents towards 200 mA, studies of instabilities and the effect of adequate countermeasures are essential for appropriate machine settings. For this purpose a new diagnostic beamline has been constructed. It is optimized for transverse and longitudinal streak camera measurements with time resolution down to one picosecond. Operation of the diagnostic beamline has recently started and first measurements are presented.

MOPC35

A Beam-Synchronous Gated Peak-Detector for the LHC Beam Observation System

LHC, CERN, longitudinal, injection

147

T.E. Levens, T. Bohl, U. Wehrle
CERN, Geneva, Switzerland

Measurements of the bunch peak amplitude using the longitudinal wideband wall-current monitor are a vital tool used in the Large Hadron Collider (LHC) beam observation system. These peak-detected measurements can be used to diagnose bunch shape oscillations, for example coherent quadrupole oscillations, that occur at injection and during beam manipulations. Peak-detected Schottky diagnostics can also be used to obtain the synchrotron frequency distribution and other parameters from a bunched beam under stable conditions. For the LHC a beam-synchronous gated peak detector has been developed to allow individual bunches to be monitored without the influence of other bunches circulating in the machine. The requirement for the observation of both low intensity pilot bunches and high intensity bunches for physics requires a detector front-end with a high bandwidth and a large dynamic range while the usage for Schottky measurements requires low noise electronics. This paper will present the design of this detector system as well as initial results obtained during the 2012-2013 LHC run.

Poster MOPC35 [2.792 MB]

MOPC39

Commissioning of a New Streak Camera at TLS for TPS Project

laser, storage-ring, longitudinal, feedback

159

C.Y. Liao, M.C. Chou, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-C. Kuo, W.K. Lau, C.Y. Wu
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a 3 GeV synchrotron light source which is being construction at campus of National Synchrotron Radiation Research Center (NSRRC) in Taiwan. A new streak camera equipped with a 125/250 MHz synchroscan unit, a fast/slow single sweep unit, and a dual-time sweep unit is prepared for beam diagnostics, especially for the TPS. An ultra short femtosecond Ti-Sapphire laser was used to evaluate the sub-picosecond temporal resolution of the streak camera and the first beam measurements of the streak camera using synchrotron light from the existing 1.5 GeV Taiwan Light Source (TLS) were performed. The commissioning results are summarized in this report.

MOPF01

Transverse Beam Size Measurements Using Interferometry at ALBA

vacuum, transverse, dipole, radiation

193

U. Iriso, L. Torino
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
T.M. Mitsuhashi
KEK, Ibaraki, Japan

Double-slit interferometry using visible light has been used for measuring the transverse beam size in different accelerators. The beam size is inferred from the analysis of the spatial coherence of the synchrotron light produced by a bending magnet. At ALBA, this technique has been implemented with moderate success, mainly limited by the present imperfections in the in-vacuum mirror that is used to extract the light out of the vacuum chamber. In this paper, we report the results obtained with the current set-up, and discuss possible improvements.

MOPF19

Injection Efficiency Monitoring System at the Australian Synchrotron

injection, booster, extraction, background

248

E.D. van Garderen, S.A. Griffiths, G. LeBlanc, S. Murphy, A. Rhyder, A. C. Starritt
ASCo, Clayton, Victoria, Australia
M.J. Boland
SLSA, Clayton, Australia

The Australian Synchrotron upgraded its user mode from decay mode to top-up mode in May 2012. To monitor the beam charge passing through the accelerator systems at key transfer points the transmission efficiency system has been upgraded. The original system could only measure the efficiency of the booster to storage ring injection. The new one calculates intermediate efficiencies between six points along the injection system, from the electron gun to the booster-to-storage ring transfer line. This is helpful to diagnose in real-time shot-to-shot the performance of the pulsed magnets, ramped magnets and ramped RF systems and their associated triggers. A software-based injection efficiency interlock has also been introduced, that can inhibit the gun when the machine settings are not optimal. This article details the architecture of the injection efficiency system and lists the improvements on the machine that have been carried out to obtain high quality data.

MOPF20

Bunch Purity Measurement for BEPCII

photon, synchrotron-radiation, radiation, electron

252

H. Jun, J.S. Cao, J.H. Junhui
IHEP, Beijing, People's Republic of China

The bunch purity is very important for time-resolved experiments. It is determined by the quality of the injection system and Touschek effect. The Beijing Electron-Positron Collider (BEPC) II was constructed for both high energy physics (HEP) and synchrotron radiation (SR) researches. It can be operated in the colliding mode and synchrotron radiation mode. It is planned to measure the beam quality in a short time of several minutes by using a timecorrelated single photon counting method. The method has a time resolution of 450 ps and a dynamic range of five orders of magnitude. In this paper, we describe our experimental set up and give a series of test results for colliding mode. We plan to set up a system which can kick out the unwanted bunches in the next stage.

MOPF26

New Booster Tune Measurement System for TLS and TPS Prototype

booster, kicker, BPM, beam-losses

271

P.C. Chiu, J. Chen, Y.-S. Cheng, K.T. Hsu, S.Y. Hsu, K.H. Hu, C.H. Kuo
NSRRC, Hsinchu, Taiwan

Taiwan Light Source (TLS) is a 1.5 GeV synchrotron based light source and its booster synchrotron was delivered in 1992. Initial booster tune measurement which adopted extraction kicker as beam excitation and use digital oscillator to extract tune was obsolete. Recently, the beam excitation device has been modified to provide more effective excitation strength and new BPM electronics is adopted to acquire tune for routine booster tune measurement. It also provides a chance to experience for the TPS project booster prototype with the similar infrastructure. Efforts will be summarized in the report.

MOPF28

Optics Non-Linear Components Measurement Using BPM Signals

optics, focusing, BPM, beam-losses

279

M. Alhumaidi, A.M. Zoubir
TU Darmstadt, Darmstadt, Germany

The knowledge of linear and non-linear errors in circular accelerator optics is very crucial for controlling and compensating resonances and their consequent beam losses. This is indispensable, especially for high intensity machines. Fortunately, the relationship between the recorded beam offset signals at the BPMs is a manifestation of the accelerator optics, and can therefore be exploited in the determination of the optics linear and non-linear components. We propose a novel method for estimating lattice non-linear components located in-between the positions of two BPMs by analyzing the beam offset signals of a BPMs triple containing these two BPMs. Depending on the non-linear components in-between the locations of the BPMs triple, the relationship between the beam offsets follows a multivariate polynomial. After calculating the covariance matrix of the polynomial terms, the Generalized Total Least Squares method is used to find the model parameters, and thus the non-linear components. Finally, a bootstrap technique is used to determine confidence intervals of the estimated values. Results for synthetic data are shown.

MOPF34

Nuclotron Deuterons Beam Parameters Measurements Using SSNTD

target, dipole, vacuum, quadrupole

299

K.V. Husak, V.V. Bukhal
The Joint Institute of Power and Nuclear Reserach - "SOSNY" NASB, Minsk, Belarus
M. Artiushenko, V.V. Sotnikov, V.A. Voronko
NSC/KIPT, Kharkov, Ukraine
A.A. Patapenka, A.A. Safronava, I.V. Zhuk
JIPNR-Sosny NASB, Minsk, Belarus

ADS are considered as prospective nuclear installations for energy production and nuclear waste transmutation or recycling. The international project “Energy and Transmutation Radioactive Wastes” running in the Laboratory of High Energy Physics at JINR (Dubna, Russia) at the accelerator complex “Nuclotron” is aimed at a feasibility study of using a deeply subcritical natural or depleted uranium or thorium active core with very hard neutron spectrum inside for effective burning of the core material together with spent nuclear fuel. For any ADS experiment a necessary and a key element is beam diagnostics. In this paper a technique for precise measurement of deuteron beam parameters using SSNTD, developed within the bounds of “E&T RAW” project, is presented. The deuteron beam parameters, specifically beam shape, size and position on a target, are obtained from track density distribution on the irradiated track detectors. The presented technique has a resolution of 1 mm. The experimental results of beam parameter measurements for deuterons with energies of 2, 4 and 8 GeV at the irradiation of the uranium subcritical assembly “QUINTA”, obtained with the SSNTD technique, are presented.

Poster MOPF34 [0.826 MB]

TUBL3

A Multiband-Instability-Monitor for High-Frequency Intra-Bunch Beam Diagnostics

LHC, CERN, SPS, pick-up

327

R.J. Steinhagen
CERN, Geneva, Switzerland
M.J. Boland, T.G. Lucas
The University of Melbourne, Melbourne, Australia

To provide the best possible luminosity, even higher beam intensities are needed in the Large Hadron Collider (LHC) and in its injector chain. This is fundamentally limited by self-amplifying beam instabilities, intrinsic to unavoidable imperfections in accelerators. Traditionally, intra-bunch or head-tail particle motion is measured using fast digitizers, which even using state-of-the-art technology are limited in their effective intra-bunch position resolution to few tens of um in the multi-GHz regime. Oscillations at this scale cause partial or total loss of the beam due to the tight transverse constraints imposed by the LHC collimation system. To improve on the present signal processing, a prototype system has been designed, constructed and tested at the CERN Super-Proton-Synchrotron (SPS) and later on LHC. The system splits the signal into multiple equally-spaced narrow frequency bands that are processed and analysed in parallel. Working with narrow-band signals in frequency-domain permits the use of much higher resolution analogue-to-digital-converters that can be used to resolve nm-scale particle motion already during the onset of instabilities.

Slides TUBL3 [3.165 MB]

TUPC08

Design and Impedance Optimization of the LNLS-UVX Longitudinal Kicker Cavity

longitudinal, kicker, impedance, feedback

369

L. Sanfelici, H.O.C. Duarte, S.R. Marques
LNLS, Campinas, Brazil

Performance evolution of parameters achieved during the electromagnetic design of the longitudinal kicker cavity for the LNLS UVX storage ring is presented. The effort on the electromagnetic optimization process of the heavily loaded cavity has been made to reach the required electrodynamic parameters of the kicker. The results for three different geometries are compared and a good compromise between the longitudinal shunt impedance and the effect of the longitudinal Higher Order Modes (HOM’s) on beam stability has been found.

Poster TUPC08 [1.365 MB]

TUPC10

Operation of Diamond Light Source XBPMs with Zero Bias

electron, DIAMOND, photon, beam-position

376

C. Bloomer, G. Rehm
Diamond, Oxfordshire, United Kingdom

Tungsten blade X-ray Beam Position Monitors (XBPMs) have been used at Diamond Light Source since 2007, however a long-standing problem with these devices has been the growth of leakage current through the ceramic insulation within the XBPMs over time, often becoming greater than 10% of the signal current after a few years of operation. The growth of these leakage currents has been found to be exacerbated by the application of a negative bias (-70V) to the tungsten blades, a bias suggested for optimum position sensitivity. This bias is applied in order to accelerate free electrons away from the surface of the blades and to prevent cross-talk, however, we have found that the operation of the XBPMs without bias has negligible impact on our measurements. Removal of the bias has been found to prevent the growth of leakage currents over time, and can also significantly reduce the cost of our signal acquisition by removing the need for a low-current amplifier with a bias supply.

Poster TUPC10 [0.455 MB]

TUPC18

Development of a Highly Efficient Energy Kicker for Longitudinal Bunch-by-Bunch Feedback

kicker, longitudinal, electron, storage-ring

407

M. Masaki, T. Fujita, K. Kobayashi, T. Nakamura, H. Ohkuma, M. Oishi, S. Sasaki, M. Shoji
JASRI/SPring-8, Hyogo-ken, Japan

A highly efficient energy kicker has been developed for longitudinal bunch-by-bunch feedback to suppress synchrotron oscillation of a high-current single electron bunch, and to cure possible longitudinal multi-bunch instability if lower beam energy is to be adopted for emittance reduction and electric power saving in a future upgrade plan of SPring-8. Through the performance test using a prototype kicker, a new water-cooled copper kicker was designed and fabricated, and it has been installed in the storage ring. The new kicker consists of three cells with each cavity length of 96 mm, its resonant frequency of 1.65 GHz, which is 3.25 times of RF frequency of the storage ring, and low Q-factor of 4.2. In beam kick test, the synchrotron oscillation amplitude of 0.64 ps was excited by kick voltage with continuous amplitude modulation at synchrotron frequency when the RF input power was 132 W/3cells. The kick voltage evaluated from the experimental result is 920 V/3cells. Shunt impedance of each kicker cell is estimated as 1.1 kΩ. As we intended, the shunt impedance per length is about three times higher than those of widely used waveguide overloaded cavity type kickers.

Poster TUPC18 [9.117 MB]

TUPC43

Bunch Length Measurement With Streak Camera At SSRF Storage Ring

electron, longitudinal, storage-ring, diagnostics

478

J. Chen, Z.C. Chen, Y.B. Leng, K.R. Ye, R.X. Yuan
SINAP, Shanghai, People's Republic of China

A streak camera is installed to measure the bunch length of storage ring at SSRF. The principle, structure, configuration and error analysis of the measurement is introduced. Some result of the measurement are analysed to explain the physical meaning of beam status. The system is used in daily operation and machine study at SSRF.

TUPF03

Performance Assessment of Wire-Scanners at CERN

LHC, SPS, CERN, laser

499

G. Baud, B. Dehning, J. Emery, J-J. Gras, A. Guerrero, E.P. Piselli
CERN, Geneva, Switzerland

This article describes the current fast wire-scanner devices installed in circular accelerators at CERN with an emphasis of the error studies carried out during the last two runs. At present the wire-scanners have similar acquisition systems but are varied in terms of mechanics. Several measurement campaigns were performed aimed at establishing optimal operational settings and to identify and assess systematic errors. In several cases the results led to direct performance improvements while in others this helped in defining the requirements for new detectors.

Poster TUPF03 [1.040 MB]

TUPF20

Low Noise and High Dynamic Range Optical Interferometer Beamsize Measurements

emittance, coupling, storage-ring, background

550

M.J. Boland
SLSA, Clayton, Australia
T.M. Mitsuhashi
KEK, Ibaraki, Japan
K.P. Wootton
The University of Melbourne, Melbourne, Australia

The technique of optical interferometry to measure beam sizes requires a low noise and high dynamic range digitisation system to push the performance to ultra low emittance on storage rings. The next generation of camera sensor Scientific CMOS (sCMOS) promises to provide the technology to improve optical interferometry. A series of measurements was performed on the Australian Synchrotron storage ring using a sCMOS and a intensity imbalance optical interferometer. The coupling in the storage ring was varied from maximum to minimum using the skew quadrupoles and the beam size at the optical diagnostic beamline was varied from over 100 microns to around 1 micron. A comparison is made between interferometer measurements using the sCMOS with and without an intensity imbalance and with previous measurements using a CCD system.

TUPF28

A Leading-Edge Hardware Family for Diagnostics Applications and Low-Level RF in CERN’s ELENA Ring

CERN, controls, antiproton, diagnostics

575

M.E. Angoletta, A. Blas, M. Jaussi, P.M. Leinonen, T.E. Levens, J.C. Molendijk, J. Sanchez-Quesada, J. Simonin
CERN, Geneva, Switzerland

The CERN Extra Low ENergy Antiproton (ELENA) Ring is a new synchrotron that will be commissioned in 2016 to further decelerate the antiprotons transferred from the CERN’s Antiproton Decelerator (AD). The requirements for the acquisition and treatment of signals for longitudinal diagnostics are very demanding, owing to the revolution frequency swing as well as to the digital signal processing required. The requirements for the Low-Level RF (LLRF) system are very demanding as well, especially in terms of revolution frequency swing, dynamic range and low noise required by the cavity voltage control and digital signal processing to be performed. Both sets of requirements will be satisfied by using a leading-edge hardware family, developed to cover the LLRF needs of all synchrotrons in the Meyrin site; it will be first deployed in 2014 in the CERN’s PSB and in the medical machine MedAustron. This paper gives an overview of the main building blocks of the hardware family and of the associated firmware and IP cores. The performance of some blocks will also be detailed.

WECL3

The LUPIN Detector: Supporting Least Intrusive Beam Monitoring Technique Through Neutron Detection

radiation, beam-losses, monitoring, proton

648

G.P. Manessi, M. Silari
CERN, Geneva, Switzerland
M. Caresana
Politecnico/Milano, Milano, Italy
M. Ferrarini
CNAO Foundation, Milan, Italy
G.P. Manessi, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
G.P. Manessi, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

The Long interval, Ultra-wide dynamic Pile-up free Neutron rem counter (LUPIN) is a novel detector initially developed for radiation protection purposes, specifically conceived for applications in pulsed neutron fields. The detector has a measurement capability varying over many orders of neutron burst intensity, from a single neutron up to thousands of interactions for each burst, without showing any saturation effect. Whilst LUPIN has been developed for applications in the radiation protection fields, its unique properties make it also well suited to support other beam instrumentation. In this contribution, the design of LUPIN is presented in detail and its main characteristics are summarized. Its potential use as beam loss monitor and complementary detector for non-invasive beam monitoring purposes (e.g. to complement a monitor based on proton beam “halo” detection) in medical accelerators is then examined. In the context of its application as a beam loss monitor for hadrontherapy accelerators, results of measurements performed at the Italian National Centre of Hadrontherapy (CNAO) are presented and analyzed.

Slides WECL3 [1.431 MB]

WEPC34

Time Trend Observation of Certain Remarked Bunches using a Streak Camera

longitudinal, injection, damping, KEK

761

T. Naito, S. Araki, H. Hayano, K. Kubo, S. Kuroda, T.M. Mitsuhashi, T. Okugi, S. Sakanaka, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan

Funding: This work is supported by Japan-U.S. cooperative program .
A streak camera with two dimensional sweep function can measure the trend of the longitudinal beam profile in the ring. In the case of the multi-bunch measurement, the different bunch profile sit on same timing, thus, we can not distinguish the behavior of each bunch. We have developed a trigger circuit to measure the bunch-by-bunch longitudinal beam profile, which uses non integer sweep frequency for the acceleration frequency. The bunch profile of each bunch sit on different position in this measurement. We observed the increment of the synchrotron oscillation amplitude from the first bunch to the 20th bunch in the KEK-ATF Damping Ring by using this system. This paper describes the hardware and the measurement results.

WEPC36

Development of Electron Bunch Compression Monitors for SwissFEL

electron, radiation, longitudinal, transverse

769

F. Frei, B. Beutner, I. Gorgisyan, R. Ischebeck, G.L. Orlandi, P. Peier, E. Prat, V. Schlott, B. Smit
PSI, Villigen PSI, Switzerland
P. Peier
DESY, Hamburg, Germany

SwissFEL will be a hard x-ray fourth generation light source to be built at Paul Scherrer Institut (PSI), Switzerland. In SwissFEL the electron bunches will be produced with a length of 3ps and will then be compressed by a factor of more than 1000 down to a few fs in order to generate ultra short x-ray pulses. Therefore reliable, accurate and noninvasive longitudinal diagnostic is essential after each compressing stage. In order to meet the requirements of this machine, new monitors have to be developed. We will present recent results of setups that measure electro-magnetic radiation, namely edge, synchrotron and diffraction radiation, emitted by the electron bunches (far field, spectral domain). These monitors are tested in the SwissFEL Injector Test Facility. A state of the art S-band Transverse Deflecting Cavity together with a Screen Monitor is used for calibration.

WEPC39

First Tests of the Top-up Gating at Synchrotron SOLEIL

injection, SOLEIL, storage-ring, kicker

775

J.P. Ricaud, L. Cassinari, P. Dumas, P. Lebasque, A. Nadji
SOLEIL, Gif-sur-Yvette, France

Since 2006, Synchrotron SOLEIL is delivering photons to its beamlines. Until 2012, thanks to the excellent performances of the injection system of the storage ring, the perturbation on the position of the stored beam was small enough to be accepted by the users. For some specific experiments, few beamlines expressed their wish to be able to stop their data acquisition during the injection. To fulfill this need, the diagnostics group of Synchrotron SOLEIL has designed the “TimEX3” board which was integrated into the timing system allowing the gating of the Top-up injection. This design was released as open hardware. Towards this aim, we decided to design it with the open source and free EDA software “KiCad”, and to make it available under the CERN’s Open Hardware Repository.

Poster WEPC39 [0.521 MB]

WEPF31

A FESA DAQ for Fast Current Transformer in SIS 18

longitudinal, CERN, SIS, pick-up

894

O. Chorniy, H. Bräuning, T. Hoffmann, H. Reeg, A. Reiter
GSI, Darmstadt, Germany

This contribution presents the development of the data acquisition (DAQ) system for the readout of fast beam current transformers (FCT) as installed in the GSI synchrotron SIS18 and as foreseen in several FAIR ring accelerators. Fast current transformers are reliable devices that offer a large analogue bandwidth and can therefore monitor bunch structures with high resolution. At appropriate sampling rates continuous measurements throughout repeated machine cycles lead to a large amount of raw data. The analysis of those raw data may range from simple bunch parameter calculations to complex longitudinal phase space reconstructions. Consequently, a new DAQ system must be carefully designed to allow for flexible acquisition modes or to allow for data reduction methods in special applications. The aims of the development are discussed and the status of the new DAQ is presented.

Poster WEPF31 [2.307 MB]

WEPF34

Accurate Measurement of Small Electron Beam Currents at the MLS Electron Storage Ring

electron, storage-ring, synchrotron-radiation, radiation

903

R. Klein, G. Brandt, D. Herzog, R. Thornagel
PTB, Berlin, Germany

The PTB, the German metrology institute, utilizes the electron storage ring MLS in Berlin Adlershof for the realization of the radiometric units in ultraviolet and vacuum ultraviolet spectral range. For this purpose the MLS can be operated as a primary source standard of calculable synchrotron radiation with very flexible parameters, especially in terms of electron beam energy and electron beam current. We report on improvements in the measurement of the electron beam current in the nA and pA range. In this range the electron beam current can be very accurately measured by counting the stored electrons.

THAL3

Charge Distribution Measurements at ALBA

photon, electron, BPM, injection

925

L. Torino, U. Iriso
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

Two different set-ups are used to perform quantitative measurements of the charge distribution at ALBA. The first consists in a real-time analysis of data coming from the Fast Current Transformer or from the buttons of a Beam Position Monitor installed in the Storage Ring. The second is performed at the diagnostic visible beamline Xanadu, using a Photomultiplier that measures the temporal distribution of synchrotron light. In both cases a quantitative estimation of the charge distribution is obtained after a dedicated data treatment and beam current measurements from the DCCT. We compare results with both methods, and discuss differences and limitations with respect to bunch purity measurements with the Time Correlated Single Photon Counting technique.

Slides THAL3 [15.369 MB]