Paper | Title | Other Keywords | Page |
---|---|---|---|
MOPG21 | Development of a Method for Continuous Functional Supervision of BLM Systems | detector, high-voltage, operation, electronics | 90 |
|
|||
It is of vital importance to provide a continuous and comprehensive overview of the functionality of beam loss monitoring (BLM) systems, with particular emphasis on the connectivity and correct operation of the detectors. At CERN, a new BLM system for the pre-accelerators of the LHC is currently at an advanced stage of development. This contribution reports on a new method which aims to automatically and continuously ensure the proper connection and performance of the detectors used in the new BLM system. | |||
![]() |
Poster MOPG21 [0.337 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG21 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPG37 | Comparative Study of Magnetic Properties for CERN Beam Current Transformers | electron, impedance, radiation, solenoid | 127 |
|
|||
At CERN, the circulating beam current measurement is provided by two types of transformer, the Direct Current Current Transformer and the Fast Beam Current Transformer. Each transformer is built based on toroidal cores made from a soft magnetic material. Depending on the type of measurement to be performed these cores require different magnetic characteristics for parameters such as permeability, coercivity and the shape of the magnetisation curve. In order to study the effect of changes in these parameters on the current transformers, several interesting raw materials based on their as-cast properties were selected. The materials have been characterised to determine their crystallisation, melting and Curie Temperatures in order to determine suitable annealing processes to tailor their properties. They have been analysed by several techniques including Electron Microscopy and X-ray Diffraction. As-cast magnetic properties such as the permeability, the B-H curve and Barkhausen noise have also been measured to enable the study of the effect of thermal treatment in the microstructure of the alloys, and the correlation of this with the change in the magnetic properties. | |||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG37 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPG09 | Novel Electrostatic Beam Position Monitors With Enhanced Sensitivity | simulation, instrumentation, quadrupole, linac | 333 |
|
|||
Beam Position Monitors (BPM) measure the beam transverse position, the beam phase with respect to the radiofrequency voltage, and give an indication on beam transverse shape. Electrostatic BPMs are composed of four electrodes that transduce the associated electromagnetic field to the beam into electrical signal allowing the calculation of the beam parameters mentioned above. During commissioning and/or experiences phases that needs very low beam current; the precision of the BPM measurements is reduced due to the low sensitivity of electrostatic BPM to beam current. This paper addresses the design, the realization and the testing of a new set of electrostatic BPMs with large electrodes. It emphasizes the strong points of these BPMs in comparison with BPMs present in SPIRAL2 facility | |||
![]() |
Poster TUPG09 [0.770 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG09 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPG15 | Intra-Train Position and Angle Stabilisation at ATF Based on Sub-Micron Resolution Stripline Beam Position Monitors | feedback, extraction, kicker, operation | 348 |
|
|||
A low-latency, sub-micron resolution stripline beam position monitoring (BPM) system has been developed and tested with beam at the KEK Accelerator Test Facility (ATF2), where it has been used to drive a beam stabilisation system. The fast analogue front-end signal processor is based on a single-stage radio-frequency down-mixer, with a measured latency of 16 ns and a demonstrated single-pass beam position resolution of below 300 nm using a beam with a bunch charge of approximately 1 nC. The BPM position data are digitised on a digital feedback board which is used to drive a pair of kickers local to the BPMs and nominally orthogonal in phase in closed-loop feedback mode, thus achieving both beam position and angle stabilisation. We report the reduction in jitter as measured at a witness stripline BPM located 30 metres downstream of the feedback system and its propagation to the ATF interaction point. | |||
![]() |
Poster TUPG15 [1.393 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG15 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPG37 | A PPS Compliant Injected Charge Monitor at NSLS-II | timing, PLC, linac, operation | 422 |
|
|||
Part of the NSLS-II Personnel Protection System (PPS), the Accumulated Charge Monitor Interlock (ACMI) was developed to ensure the Accelerator Safety Envelope (ASE) limits for charge generation in the NSLS-II Injector are never violated. The ACMI measures the amount of charge in each injection shot using an Integrating Current Transformer (ICT). For logistical reasons, adding a redundant ICT was impractical so in order to achieve the high reliability required for PPS this system is designed to perform self-tests by injecting calibrated charge pulses into a test coil on the ICT and analyzing the returning charge signal. The injector trigger rate is 1.97Hz and self-tests are performed 250 mSec after every trigger pulse. Despite the lack of a redundant charge measurement the ACMI achieved the high reliability rating required for PPS with a mean time between failure (MTBF) rate greater than 106 hours. The ACMI was commissioned in 2014 and has operated to date without any major problems. In 2015 a second ACMI system was commissioned at another location in the injection system. | |||
![]() |
Poster TUPG37 [2.212 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG37 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPG38 | A PPS Compliant Stored Beam Current Monitor at NSLS-II | operation, storage-ring, PLC, diagnostics | 426 |
|
|||
A requirement for top-off operations at the NSLS-II facility is at least 50mA stored ring current. The Stored Beam Current Monitor (SBCM) is part of the NSLS-II Personnel Protection System (PPS) that determines the storage ring current based on Pick-Up Electrode (PUE) readings. The SBCM selects the 500 MHz component of the PUE signal and downconverts it to about 2 MHz. The 2 MHz signal is rectified, averaged down to a bandwidth of 500 Hz, and compared to a threshold voltage equivalent to 55mA of stored beam. A redundant SBCM system was also constructed and these two systems must agree that the stored beam is above the threshold to enable top-off operations. The SBCM is also required to remain accurate over wide range of possible bunch patterns and bunch intensity distributions. Under normal conditions for top-off operations the SBCM measurement accuracy is about 1%. The SBCM was commissioned in 2015 as part of the Top-Off Safety System (TOSS) which is responsible for ensuring safe top-off operations at NSLS-II. | |||
![]() |
Poster TUPG38 [2.834 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG38 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPG43 | The Next Generation of Cryogenic Current Comparators for Beam Monitoring | cryogenics, shielding, niobium, operation | 441 |
|
|||
Funding: Federal Ministry of Education and Research- BMBF, contract: 05P15SJRBA A new Cryogenic Current Comparator with eXtended Dimensions (CCC-XD) is currently under development for a non-destructive, highly sensitive monitoring of nA-intensities of beams for larger beamline diameters planned for the new FAIR accelerator facility at GSI. The CCC consists of a superconducting coil which is read out by a Superconducting Quantum Interference Device (SQUID), a flux concentrator and a superconducting shield. The new flux concentrator comprises of a specially designed, highly permeable core made of nanocrystalline material in order to assure a low-noise operation and a high system bandwidth of up to 200 kHz. The superconducting shielding of niobium has extended geometric dimensions and will suppress disturbing magnetic fields of the beamline environment effectively. New SQUID sensors with sub-μm-Josephson junctions enable extreme low-noise signals and high disturbance-suppression. The CCC-XD system and the new dedicated cryostat will be ready for testing in the CRYRING at GSI in 2017. Results from electrical measurements with the components of the new CCC-XD Setup will be presented in this work. |
|||
![]() |
Poster TUPG43 [4.019 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG43 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPG01 | Numerical Comparative Study of BPM Designs for the HESR at FAIR | pick-up, simulation, emittance, software | 608 |
|
|||
The institute of Nuclear Physics 4(IKP-4) of the Research Center Jülich (FZJ) is in charge of building and commissioning the High Energy Storage Ring (HESR) within the international Facility for Antiproton and Ion Research (FAIR) at Darmstadt. Simulations and numerical calculations were performed to characterize the BPM pickup design that is currently envisaged for the HESR, i.e. a diagonally cut cylindrical pickup. The equivalent circuit has been studied with emphasis on capacitive cross coupling. Based on our findings, performance increasing changes could be introduced. A prototype BPM was constructed and tested on a test bench. A comparison of results is presented. Another proposed design was characterized, as a symmetric coupling behavior is expected. That is a symmetrical straight four-strip geometry. Additionally an extensive study was conducted to see effects due to manufacturing tolerances. Driven by curiosity an eight-strip design was considered, which would allow for beam size measurements. First results for this configuration are shown. Used methodology, tools and results of expected signal level and sensitivity distributions are presented as well. | |||
![]() |
Poster WEPG01 [2.172 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG01 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPG03 | HOM Characterization for Beam Diagnostics at the European XFEL Injector | HOM, cavity, dipole, electron | 616 |
|
|||
Funding: The work is part of EuCARD-2, partly funded by the European Commission, GA 31245. Higher Order Modes (HOM) excited by bunched elec-tron beams in accelerating cavities carry information about the beam position and phase. This principle is used at the FLASH facility, at DESY, for beam position monitoring in 1.3 and 3.9 GHz cavities. Dipole modes, which depend on the beam offset, are used. Similar monitors are now under design for the European XFEL. In addition to beam position, the beam phase with respect to the accelerating RF will be monitored using monopole modes from the first higher order monopole band. The HOM signals are available from two couplers installed on each cavity. Their monitoring will allow the on-line tracking of the phase stability over time, and we anticipate that it will improve the stability of the facility. As part of the monitor designing, the HOM spectra in the cavities of the 1.3 and 3.9 GHz cryo-modules installed in the European XFEL injector have been measured. This paper will present their dependence on the beam position. The variation in the modal distribution from cavity to cavity will be discussed. Based on the results, initial phase measurements based on a fast oscilloscope have been made. |
|||
![]() |
Poster WEPG03 [3.281 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG03 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPG07 | A Heterogeneous FPGA/GPU Architecture for Real-Time Data Analysis and Fast Feedback Systems | GPU, FPGA, detector, data-analysis | 626 |
|
|||
We propose a versatile and modular approach for a real-time data acquisition and evaluation system used for monitoring and feedback control in beam diagnostic and photon science experiments. Our hybrid architecture is based on an FPGA readout card* and a GPU for data processing. To increase throughput, lower latencies and reduce overall system strain, the FPGA write data directly in the GPU. After real-time data analysis the GPU writes back results either directly to the FPGA in case of fast feedback systems or to the CPU host system for storage. Communication and scheduling are handled transparently by our processing framework**. However, users can customize and extend it with their own processing plugins. Although the system is designed for real-time purposes, the modular approach also allows standalone usage for high-speed off-line analysis. We evaluated the performance of our solution measuring both processing times of data analysis algorithms used with beam instrumentation detectors as well as transfer times between FPGA and GPU. The latter suggests throughputs of up to 6.5 GB/s with latencies down to tens of microseconds, thus making it suitable for fast feedback systems.
* A PCIe DMA Architecture for Multi-Gigabyte Per Second Data Transmission, 10.1109/TNS.2015.2426877 ** A Scalable GPU-based Image Processing Framework for On-line Monitoring, 10.1109/HPCC.2012.116 |
|||
![]() |
Poster WEPG07 [17.144 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG07 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPG37 | Nondestructive High-Accuracy Charge Measurement of the Pulses of a 27 MeV Electron Beam from a Linear Accelerator | linac, electron, radiation, vacuum | 708 |
|
|||
This work presents a description of measuring devices and procedures in order to enable the nondestructive (non-intercepting) absolute measurement of the charge of individual beam pulses (macro-pulses) from an electron linear accelerator with high accuracy, i.e. with a measurement uncertainty <0.1%. In particular, we demonstrate the readout and calibration of a Bergoz integrating current transformer which is frequently applied at many different types of accelerators as a beam intensity monitor. The current transformer signal is calibrated against a custom-made compact Faraday cup with a high degree of collection efficiency for electron beams in the energy range of 6 MeV to 50 MeV (99.2 % at 27 MeV), which is well known from measurements and Monte Carlo calculations. | |||
![]() |
Poster WEPG37 [1.513 MB] | ||
DOI • | reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG37 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||