Keyword: storage-ring
Paper Title Other Keywords Page
MOPB09 Comparison Among Different Tune Measurement Schemes at HLS-II Storage Ring betatron, pick-up, detector, experiment 93
 
  • L.T. Huang, X.Y. Liu, P. Lu, M.-X. Qian, B.G. Sun, J.G. Wang, J.H. Wei, F.F. Wu, Y.L. Yang, T.Y. Zhou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Tune measurement is one of the most significant beam diagnostics at HLS-II storage ring. When measuring tune, higher tune spectral component and lower other compo-nents are expected, so that the tune measurement will be more accurate. To this end, a set of BBQ (Base Band Tune) front-end based on 3D (Direct Diode Detection) technique has previously developed to improve the effec-tive signal content and suppress other components. Em-ploying the BBQ front-end, four different tune measure-ment schemes are designed and related experiments per-formed on the HLS-II storage ring. Experimental results and analysis will be presented later.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB09  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPB14 SSRF Beam Operation Stability Evaluation Using Bunch by Bunch Beam Position Method* injection, SRF, damping, operation 104
 
  • N. Zhang
    SSRF, Shanghai, People's Republic of China
  • Y.B. Leng, Y.M. Zhou
    SINAP, Shanghai, People's Republic of China
 
  Funding: * Work supported by National Natural Science Foundation of China (No.11575282 No.11375255 No.11305253)
In order to improve the efficiency and quality of light in top-up mode at SSRF, disturbance caused by leakage fields mismatch during injection should be minimized and stable. This could be evaluated by analysis of bunch by bunch residual betatron oscillation data, using this method, instability of tune distribution and damping repeatability could also be calculated. So we could evaluate the beam operation stability by the data analysis and discuss in the paper.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB14  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPC02 Identification of Faulty Beam Position Monitor Based Clustering by Fast Search and Find of Density Peaks SRF, electron, operation, experiment 114
 
  • R. Jiang, Y.B. Leng
    SSRF, Shanghai, People's Republic of China
  • F.Z. Chen, Z.C. Chen, Y.B. Leng
    SINAP, Shanghai, People's Republic of China
 
  The accuracy and stability of beam position moni-tors(BPMs) are important for all kinds of measurement systems and feedback systems in particle accelerator field. A proper method detecting faulty beam position monitor or monitoring their stability could optimize accel-erator operating conditions. With development in ma-chine learning methods, a series of powerful analysis approaches make it possible for detecting beam position monitor's stability. Here, this paper proposed a clustering analysis approach to detect the defective BPMs. The method is based on the idea that cluster centres are char-acterized by a higher density than their neighbours and by a relatively large distance from points with higher densi-ties. The results showed that clustering by fast search and find of density peaks could classify beam data into dif-ferent clusters on the basis of their similarity. And that, aberrant data points could be detected by decision graph. So the algorithm is appropriate for BPM detecting and it could be a significant supplement for data analysis in accelerator physics.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPC03 Precise Measurement of Small Currents at the MLS electron, radiation, experiment, synchrotron 118
 
  • Y. Petenev, J. Feikes, J. Li, A.N. Matveenko, Y. Tamashevich
    HZB, Berlin, Germany
  • R. Klein, J. Lubeck, R. Thornagel
    PTB, Berlin, Germany
 
  The Physikalisch-Technische Bundesanstalt (PTB), the National Metrology Institute of Germany, utilizes an electron storage ring - the Metrology Light Source (MLS), located in Berlin, as a radiation source standard in the VIS, UV and VUV spectral range. In order to be able to calculate the absolute intensity of the radiation, the electron beam current has to be measured with low uncertainty. In this paper we focus on the measurement of the beam current in a range of several nA to 1 pA (one electron) by means of Si photodiodes, detecting synchrotron radiation from the beam. Electrons are gradually scraped out of the ring and the diode signal is analyzed afterwards. The exact number of stored electrons then can be derived from the signal. The measurement is carried out automatically with an in-house developed software.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC03  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPC16 The Development and Applications of Digital BPM Signal Processor on SSRF SRF, brilliance, controls, FEL 147
 
  • L.W. Lai, F.Z. Chen, Y.B. Leng, Y.B. Yan, N. Zhang, W.M. Zhou
    SSRF, Shanghai, People's Republic of China
 
  The development of Digital BPM Signal Processors (DBPM) for SSRF started from 2008. The first prototype for SSRF storage ring was completed in 2012, with turn-by-turn resolution better than 1μm. From 2016 to 2017, SSRF successively constructed two FEL facilities in China, DCLS and SXFEL test facilities. The second ver-sion DBPM was developed and used in large scale during this period to meet the requirements of signal processing for stripline BPMs and cavity BPMs. After that, we turned to the development of DBPM for SSRF storage ring based on the second version hardware, including FPGA firmware, EPICS IOC, EDM control panel. The development was completed and tests were carried out in early 2018. Test results showed that the position data is accurate and can monitor beam movement correctly, and online turn-by-turn position data resolution reaches 0.46μm. This paper will introduce the design of DBPM for the SSRF storage ring and the tests carried out to verify the data accuracy and evaluate the system performance.  
poster icon Poster MOPC16 [1.372 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPC16  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUOB03 Demonstration of a Newly Developed Pulse-by-pulse X-Ray Beam Position Monitor in SPring-8 detector, radiation, operation, vacuum 182
 
  • H. Aoyagi, Y. Furukawa, S. Takahashi, A. Watanabe
    JASRI/SPring-8, Hyogo, Japan
 
  Funding: This work was partly supported by Japan Society for the Promotion of Science through a Grant-in-Aid for Scientific Research (c), No. 20416374 and No. 18K11943.
A newly designed pulse-by-pulse X-ray beam position monitor (XBPM), which is photoemission type, has been demonstrated successfully in the SPring-8 synchrotron radiation beamline. Conventional XBPMs work in the direct-current (DC) mode, because it is difficult to measure a beam position in the pulse mode under the sever heat load condition. The key point of the design is aiming at improving heat-resistance property without degradation of high frequency property [1]. This monitor is equipped with microstripline structure for signal transmission line to achieve pulse-by-pulse beam position signal. A photocathode is titanium electrode that is sputtered on a diamond heat sink to achieve high heat resistance. We have manufactured the prototype, and demonstrated feasibility at the SPring-8 bending magnet beamline. As a result, we observed a unipolar single pulse with the pulse length of less than 1 ns FWHM and confirmed that it has pulse-by-pules position sensitivity [2]. Furthermore, this monitor can be also used in the direct-current mode with good stability and good resolution. The operational experience will be also presented.
[1] http://accelconf.web.cern.ch/AccelConf/medsi2016/papers/wepe10.pdf
[2] http://www.pasj.jp/webpublish/pasj2017/proceedings/PDF/THOM/THOM06.pdf
 
slides icon Slides TUOB03 [2.380 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUOB03  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPA03 Test of New Beam Loss Monitors for SOLEIL detector, controls, electron, shielding 215
 
  • N. Hubert, M. El Ajjouri, D. Pédeau
    SOLEIL, Gif-sur-Yvette, France
 
  Soleil is currently testing new beam loss monitors to replace its pin-diode based existing system. The new detectors are made of plastic scintillators associated with photomultiplier and connected to Libera BLM dedicated electronics. This new detector should provide both fast (turn by turn) and slow (averaged) loss measurements, post mortem capabilities and should be less sensitive to the beam directivity compared to the pin-diodes. Different methods for a relative calibration of the modules are under investigation, either using a diode (LED) or a cesium radioactive source. Calibration results and first measurements with beam are presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPA03  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPB04 Development of a New Button Beam-position Monitor for BESSY VSR impedance, vacuum, resonance, operation 265
 
  • J.G. Hwang, V. Dürr, M. Ries, A. Schälicke, G. Schiwietz, D. Wolk
    HZB, Berlin, Germany
 
  An extreme operation mode such as the BESSY-VSR conditions stimulates the development of a high accuracy bunch-by-bunch beam-position monitor (BPM) system which is compatible with the bunch-selective operation for the orbit feedback system. Such a system will also greatly benefit to accelerator R&D such as transverse resonance island buckets (TRIBs). Compensation of the long-range ringing signal produced by the combined effect of impedance mismatching inside the button and trapped TE-modes in the aluminum-oxide insulator (Al2O3) material is required essentially to improve the resolution. This is important since the ringing causes a misreading of the beam position and current of following bunches. We show the design study of a new button-type BPM to mitigate the influence of the ringing signal as well as to reduce wake losses by improving the impedance matching in the button and by replacing the insulator material.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPB04  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPC01 Australian Synchrotron BPM Electronics Upgrade electron, brilliance, coupling, synchrotron 297
 
  • Y.E. Tan, R.B. Hogan
    AS - ANSTO, Clayton, Australia
 
  The storage ring at the Australian Synchrotron (AS) was originally equipped with 98 Libera Electrons. In late 2017 all 98 of the BPM electronics has been upgraded to Libera Brilliance+ and the old Libera Electrons have been moved to the injection system. The transition process and results from commissioning the new system will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC01  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPC12 Beam Transverse Quadrupole Oscillation Measurement in the Injection Stage for the HLS-II Storage Ring quadrupole, injection, betatron, electron 325
 
  • F.F. Wu, F.L. Gao, L.T. Huang, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, J.H. Wei, T.Y. Zhou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Funding: Supported by the National Science Foundation of China (Grant No. 11705203, 11575181, 11605202) and the National Key Research and Development Program of China(No. 2016YFA0402000)
Beam transverse quadrupole oscillation can be excited in the injection stage if injected beam parameters(twiss parameters or dispersion) are not matched with the parameters in the injection point of the storage ring. In order to measure the beam transverse quadrupole oscillation in the injection stage for the HLS-II storage ring, some axially symmetric stripline BPMs were designed. Transverse quadrupole component for these BPMs was simulated and off-line calibrated. Beam transverse quadrupole oscillation has been measured when beam was injected into the HLS-II electron storage ring. The spectrum of the transverse quadrupole component showed that beam transverse quadrupole oscillation is very obvious in the injection stage and this oscillation isn't the second harmonic of beam betatron oscillation. The relationship between transverse quadrupole oscillation and beam current was also analyzed and the result shows that the relationship is not linear.
 
poster icon Poster TUPC12 [0.467 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC12  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOB02 RadFET Dose Monitor System for SOLEIL radiation, electron, electronics, vacuum 353
 
  • N. Hubert, F. Dohou, M. El Ajjouri, D. Pédeau
    SOLEIL, Gif-sur-Yvette, France
 
  Soleil is currently testing new dose monitors based on RadFET transistors. This new detector at SOLEIL will provide a measurement of the dose received by equipment that are damaged by the radiations in the storage ring, and to anticipate their replacement. This monitor should be very compact to be placed in tiny areas, sensitive to all kind of radiation and low cost to install many of them around the ring. A readout electronic module is being developed in-house, and a first prototype has been build and installed on the machine. Description of the system and first results recorded on the machine are presented.  
slides icon Slides WEOB02 [4.250 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEOB02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPB18 Performance of a Reflective Microscope Objective in an X-ray Pinhole Camera target, photon, electron, emittance 477
 
  • L. Bobb, G. Rehm
    DLS, Oxfordshire, United Kingdom
 
  X-ray pinhole cameras are used to measure the transverse beam profile of the electron beam in the storage ring from which the emittance is calculated. As improvements to the accelerator lattice reduce the beam emittance, e.g. with upgrades to fourth generation synchrotron light sources, likewise the beam size will be reduced such that micron and sub-micron scale resolution is required for beam size measurement. Therefore the spatial resolution of the pinhole camera imaging system must be improved accordingly. Here, the performance of a reflective microscope objective is compared to the high quality refractive lens which is currently in use to image the scintillator screen to the camera. The modulation transfer functions for each system have been assessed and will be discussed.  
poster icon Poster WEPB18 [0.751 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB18  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPC15 Machine Learning Applied to Predict Transverse Oscillation at SSRF diagnostics, SRF, injection, network 512
 
  • B. Gao, J. Chen, Y.B. Leng, Y.M. Zhou
    SINAP, Shanghai, People's Republic of China
 
  A fast beam size diagnostic system has been developed at SSRF (Shanghai Synchrotron Radiation Facility) storage ring for turn-by-turn and bunch-by-bunch beam transverse oscillation study. This system is based on visible synchrotron radiation direct imaging system. Currently, this system already has good experimental results. However, this system still has some limitations, the resolution is subject to the point spread function and the speed of online data processing is limited by the complex algorithm. We present a technique that applied machine learning tools to predict transverse oscillation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPC15  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THOB02 Energy Loss Measurements with Streak Camera at ALBA injection, simulation, synchrotron, insertion 548
 
  • A.A. Nosych, B. Bravo, U. Iriso
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  Analyzing streak camera images of the beam injected into a Storage Ring with no RF voltage allows calculating several parameters, like the energy loss per turn and the energy mismatch between injected and stored beams. These measurements are based on the analysis of the centroid drift path of a bunch as it spirals inwards, changing its rotation period. This drift is clear and measurable in single and multi-bunch modes in several horizontal sweep speeds of the streak. With this technique we also measure the momentum compaction factor and observe its change with respect to the insertion devices' open/closed states. The obtained values are comparable with theoretical expectations, as well as with values measured by other means.  
slides icon Slides THOB02 [3.030 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-THOB02  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)