Paper | Title | Other Keywords | Page |
---|---|---|---|
MOCO02 | Development of a Passive Cavity Beam Intensity Monitor for Pulsed Proton Beams for Medical Applications | cavity, proton, linac, booster | 41 |
|
|||
Funding: This work has been funded by the Innovation Department of Regione Lazio Government, Italy. In this work the design of a passive cavity beam intensity monitor to be used in the TOP-IMPLART medical proton linac for the on-line measurement of beam current is presented. It will be used to monitor the beam between modules and at the linac exit. TOP-IMPLART produces a pulsed proton beam with 3 us duration at 200 Hz repetition rate with a current between 0.1 uA and 50 uA. The current required for medical applications is less than 1 uA and has to be known with an accuracy better than 5%. Large dynamic range and space constraints make the use of usual non-interceptive beam diagnostics unfeasible. The proposed system consists of a resonant cavity working in the TM010 mode, generating an electromagnetic field when the beam enters the cavity; a magnetic pickup senses an RF pulse whose amplitude is proportional to the current. The RF pulse is amplified and subsequently detected with zero-biased Schottky diodes. The cavity operates in vacuum when used in the inter-module space. The work reports also the results of preliminary measurements done on an copper prototype in air at the exit of the TOP-IMPLART linac to test the sensitivity of the system on the actual 35 MeV proton beam. |
|||
Slides MOCO02 [3.269 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOCO02 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP006 | Commissioning of the Beam Loss Monitoring system for the HADES beam-line at GSI | detector, proton, operation, heavy-ion | 74 |
|
|||
The High Acceptance Di-Electron Spectrometer experiments at GSI (HADES) require high-intensity heavy ion beams. Monitoring and minimization of the beam losses are critical for the operation at the desired beam intensities. FAIR-type Beam Loss Monitor (BLM) system based on sixteen plastic scintillator detectors is installed along the beam line from the SIS-18 synchrotron to the experiment location. The detectors are used in counting mode, with maximum counting rate of order of 20 MHz. The system has been commissioned during the 2018 beam time. Details on the detector setup, its calibration procedure and how it can be used for quantitative beam loss determination are presented. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP006 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP007 | Versatile Beamline Cryostat for the Cryogenic Current Comparator (CCC) for FAIR | cryogenics, resonance, vacuum, operation | 78 |
|
|||
Funding: Work supported by AVA - Accelerators Validating Antimatter the EU H2020 Marie-Curie Action No. 721559 and by the BMBF under contract No. 05P15SJRBA and 5P18SJRB1. The Cryogenic Current Comparator (CCC) extends the measurement range of traditional non-destructive current monitors used in accelerator beamlines down to a few nano-amperes of direct beam current. This is achieved by a cryogenic environment of liquid helium around the beamline, in which the beam’s magnetic field is measured with a Superconducting Quantum Interference Device (SQUID), which is itself enclosed in a superconducting shielding structure. For this purpose, a versatile UHV-beamline cryostat was designed for the CCCs at FAIR and is currently in production. It is built for long-term autonomous operation with a closed helium re-liquefaction cycle and with good access to all inner components. The design is supported by simulations of the cryostat’s mechanical eigenmodes to minimize the excitation by vibrations in an accelerator environment. A prototype at GSI has demonstrated the self-contained cryogenic operation in combination with a 15 l/day re-liquefier. The cryostat will be used in CRYRING to compare the FAIR-CCC-X with newly developed CCC-types for 150 mm beamlines. Both which will supply a nA current reading during commissioning and for the experiments. |
|||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP007 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP009 | Retrieving Beam Current Waveforms from ACCT Output Using Experimental Response Function for Use in Long Pulse Accelerators | FPGA, experiment, distributed, timing | 85 |
|
|||
Current transformers (ACCT/DCCT) are used as non-interceptive means of beam current measurement in many accelerators. In the case of long pulse to CW accelerators for fusion neutron sources such as IFMIF, A-FNS, etc., current measurement using current transformers for pulses with around 10-100 ms or longer suffer such problems as drooping and the measurement accuracy is deteriorated. So, improving the accuracy for long pulse beams is highly required. We have proposed a method for retrieving the beam currents from the ACCT output using the transfer function obtainable from simple experiments. It was confirmed from numerical calculation that beam currents longer than a second could be theoretically retrieved*. The effects of associated circuits and cables such as stray capacitance, inductance and magnetic materials nearby are inherently included in the transfer function. We are working for implementing this method into FPGA. For calculation convenience, the transfer function is converted into a form of impulse function and the convolution with the digitized ACCT output is to be carried out to retrieve the beam current. The theory, algorithm and design will be discussed.
Y. Hirata, et al., IEEE Trans. Plasma Sci., Vol. 46 (2018), pp. 2272. |
|||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP009 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP010 | Design and Properties of a New DCCT Chamber for the PF-Ring at KEK | impedance, operation, HOM, cavity | 91 |
|
|||
A DC current transformer (DCCT) for the PF-ring was renewed during the 2018 summer shutdown. A vacuum chamber for the new DCCT was designed based on a circular duct with an inner diameter of 100 mm and has a structure housing a toroidal core inside of electromagnetic shields. The geometry of the ceramic break for interrupting the wall current flow was optimized using a three-dimensional electromagnetic field simulator, and the break was fabricated considering some technical limitations. Both ends of the ceramic break were short-circuited in a high-frequency manner by a sheet-like capacitive structure to suppress the radiation of unneeded higher-order modes (HOMs) into the core housing. The ceramic break is also equipped with water-cooling pipes on metal sleeves brazed to the both ends to efficiently remove the heat generated by HOMs. The new DCCT chamber has been used already in user operation without any problems. A temperature rise near the ceramic break is still approximately six degrees Celsius, even when a 50-mA isolated bunch is stored. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP010 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 07 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP015 | Charge Detection System for the CLARA/VELA Facility | MMI, experiment, feedback, controls | 111 |
|
|||
The CLARA/VELA facility at Daresbury Laboratory combines an FEL test facility and an electron accelerator for scientific and industrial applications, capable of providing up to 40 MeV electrons, with an eventual goal of 250 MeV. Accurate measurement of the bunch charges in a wide range (1 - 250 pC) at a repetition rate up to 400 Hz is required. We present a new system of analogue electronics developed to interface with existing and future bunch charge measurement devices (wall current monitors, faraday cups, etc.) to measure the bunch charges accurately and precisely. The system is based on a charge amplifier with switchable sensitivity, dark current gating and on-board self-calibration. Results of circuit simulations, offline calibration tests and online beam tests of a prototype system are presented. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP015 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 07 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP026 | A Longitudinal Kicker Cavity for the BESSY II Booster | cavity, kicker, booster, feedback | 150 |
|
|||
As part of the global refurbishment of the injector systems at BESSY II, a new longitudinal kicker cavity and suitable feedback will be installed in the booster. Both a flexible bunch charge and spacing is essential for efficient injection. Such a cavity is needed to mitigate the unwanted couple bunch instabilities associated with these elaborate filling patterns and the HOMs of additional accelerating structures. This paper covers the conceptual design, simulation strategy, manufacture and bench tests of the longitudinal kicker cavity before it is installed in the ring. | |||
Poster MOPP026 [4.756 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP026 | ||
About • | paper received ※ 02 September 2019 paper accepted ※ 07 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
MOPP047 | Design and Development of Beam Diagnostics for an FFA-FFA Ring for ISIS-II Upgrade Studies | vacuum, detector, GUI, proton | 214 |
|
|||
The ISIS-II project aims to deliver a new spallation neu- tron source by 2034, driven by a 1.2 GeV proton accelerator capable of delivering a beam power of 1.25 MW with a rep- etition rate of 50 Hz or higher. One of the options for this future accelerator is a Fixed Field alternating gradient Accelerator (FFA). To demonstrate the suitability of FFAs for use in a user facility such as ISIS, there is a plan to construct a smaller scale proof of concept machine: FETS-FFA. Developing beam diagnostics for the FETS-FFA ring presents a challenge due to a large orbit excursion and aperture ( 60 mm x 700 mm). Diagnostics must cover the full size of beam chamber whilst still providing measurement sensitivity and resolution comparable to that seen in the ISIS synchrotron. This paper presents the current design and development of beam diagnostics for the FETS-FFA ring, including finite element studies of Beam Position Monitors (BPMs) and Ionisation Profile Monitors (IPMs). | |||
Poster MOPP047 [9.355 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOPP047 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 07 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUBO04 | Measuring the Beam Profile by Counting Ionization Electrons | electron, detector, vacuum, proton | 257 |
|
|||
The principle of non-destructive beam profile measurement with rest gas ionization electrons has remained largely unchanged since the technique was first proposed in the late 1960¿s. Ionization electrons (or ions) are transported by an electrostatic field onto an imaging detector, where the spatial distribution of detected electrons is a direct measure of the transverse beam profile. The detector typically consists of one or more Micro-Channel Plates (MCP’s) to amplify the signal, followed by either a phosphor screen and camera, or pickup electrodes. A long-standing problem is the ageing of the MCP’s, which limits the accuracy of the beam profile measurement. A new technique to detect ionization electrons has been developed at CERN, which uses a hybrid pixel detector to detect single ionisation electrons. This allows the application of counting statistics to the beam profile measurement. It will be shown that a meaningful beam profile can be extracted from only 100 electrons. Results from the new instrument will be presented, which demonstrate the ability to measure the beam profile of single bunches turn-by-turn, which offers new opportunities for beam diagnostic insights. | |||
Slides TUBO04 [2.199 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUBO04 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP008 | Thermal Simulations of Optical Transition Radiation Targets | target, radiation, linac, emittance | 297 |
|
|||
Funding: Work supported by DFG through GRK 2128 The recirculating electron linac S-DALINAC* provides beams with currents up to 20 µA and energies up to 130 MeV. It is planned to extend the beam diagnostics by adding multiple emittance measurement systems in order to investigate the emittance evolution along the beamline. The emittance measurement is based on the quadrupole scan technique and utilizes the existing quadrupoles and newly built optical transition radiation targets. As the targets are heated by the beam and destruction must be avoided, simulations of the thermal behaviour of the target were conducted. In particular, the dependence of the target temperature on the target design, but also variable parameters as beam spot size and current were investigated. This contribution will present these parameter studies. * N. Pietralla, Nuclear Physics News, Vol. 28, No. 2, 4 (2018) |
|||
Poster TUPP008 [1.114 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP008 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP012 | Image of the Transverse Bunch Profile via COTR | electron, radiation, laser, target | 313 |
|
|||
Funding: This work was supported by the grant of the Russian Ministry of Science # 3/1903.2017. Transverse beam profile diagnostics based on Optical Transition Radiation (OTR) is a routine technique at most modern electron linear accelerators (linacs) which is difficult to implement for FEL beams [*] and LWPA accelerators [**]. The reason is that a standard OTR beam profile monitor with a few micrometers space resolution cannot be used for measurements of ultrashort bunch profiles due to coherent effects in the OTR emission process [***]. We have developed an approach which allows calculating the propagation of coherent optical transition radiation (COTR) through a standard optical system consisting of a focusing lens and a spatial resolving detector placed in the image plane. Strict summation of the OTR fields emitted coherently by electrons inside the bunch and its focusing onto the detector plane allows obtaining a COTR image of the bunch profile. With the assumption of a Gaussian transverse bunch profile it is shown that the resulting image has a typical "ring" shape, characteristics of which are depended on the bunch transverse rms size and optical system parameters. * E. Saldin, et al., "The Physics of Free Electron Lasers", Springer-Verlag, 2010. ** N. Bourgeois, et al., AIP Conf. Proc., 1507, 258 (2012). *** H. Loos, R. Akre, et al., SLAC-PUB-13395 (2008). |
|||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP012 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP024 | Development of a Beam Induced Fluorescence Monitor for Non-Destructively Profiling MW Proton Beam at the J-PARC Neutrino Beamline | injection, photon, proton, vacuum | 358 |
|
|||
A Beam Induced Fluorescence (BIF) monitor is under development for non-destructively monitoring the future MW-power proton beam at the neutrino extraction beamline at J-PARC. The §I{30}{GeV} protons are bombarded onto a graphite target, producing one of the most intense neutrino beams in the world for the Tokai-to-Kamioka (T2K) long-baseline neutrino oscillation experiment, where beam profile monitoring is essential for protecting beamline equipment and understanding the neutrino flux. For the BIF monitor, gas is injected into the beam pipe and the spatial distribution of the fluorescence light induced by proton-gas interactions is measured, allowing us to continuously and non-destructively monitor the proton beam profile. However, the specifications of the beamline require us to carefully control the gas localization by pulsed injection. Radiation hardness of all monitor components and profile distortion caused by space charge effects must also be considered. We will show how to address these challenges and realize a working prototype. | |||
Poster TUPP024 [8.094 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP024 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP025 | The Installation and Application of Multi-wire Profile Monitor for PBW in CSNS | target, proton, experiment, electron | 363 |
|
|||
To monitor the size and position of 1.6 Gev proton beam in front of proton beam window(PBW) of China spallation neutron source (CSNS), one multi-wire profile monitor (MWPM) is designed and installed with PBW. It can bear the heat caused by beam and generate signal to electronic in local station. We can monitor the situation of beam and protect PBW using MWPM. | |||
Poster TUPP025 [0.514 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP025 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 08 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP035 | Development of Modular Spare Parts for the Profile and Position Monitors of the 590 MeV Beam Line at HIPA | shielding, vacuum, pick-up, target | 402 |
|
|||
A new generation of monitor plugs is under development for the ageing wire profile monitors and beam position monitors which are inserted into massive shielding of the 590 MeV proton beam line at HIPA. The modular mechanical design, aspects of handling, vacuum compatibility, radiation hardness, shielding, cabling and monitor environment are discussed. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP035 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP036 | Performance of an In-Air Secondary Emission Grid Profile Monitor at the ISIS Neutron and Muon Source | target, focusing, data-acquisition, neutron | 407 |
|
|||
The ISIS neutron and muon source, located in the UK, consists of an H− linear accelerator, a rapid cycling proton synchrotron and extraction lines to two target stations. A project is currently under way to replace the target assembly of the First Target Station (TS1) in order to secure its continued operation and improve operational flexibility. In addition to a number of other diagnostic tools, a new secondary emission (SEM) grid profile monitor is expected to be located within the helium atmosphere of the new target assembly. To investigate the performance of an out-of-vacuum SEM grid, a prototype monitor was positioned in-air between a beam exit window and a dump. Profile measurements taken with this monitor are presented, including tests at a range of bias voltages with a fast data acquisition system to investigate secondary signal sources. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP036 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 07 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP037 | Studies of the Time Structure of Ionisation Beam Profile Measurements in the ISIS Extracted Proton Beamline | space-charge, proton, synchrotron, electron | 412 |
|
|||
Ionisation Profile Monitors (IPMs) are used at the ISIS neutron and muon source to perform non-destructive transverse beam profile measurements. An in-house particle tracking code, combined with 3D CST modelling of the electric fields within the monitors, has been used to improve understanding of the various error sources within the IPMs, and shows close agreement with profile measurements in the synchrotron. To allow for detailed benchmarking studies, an IPM has been installed in Extracted Proton Beamline 1 (EPB1), enabling comparison with secondary emission (SEM) grid measurements. However, the IPM measurements taken in EPB1 show increased levels of profile broadening at operational beam intensities, which are not reproduced by SEM measurements or simulation. To investigate these differences, studies of the time structure of measured profiles are being performed. This paper details the development of new, high-speed multichannel data acquisition electronics, required to perform these studies. Resulting measurements are discussed, along with an analysis of the data¿s time structure and a comparison with that predicted by the IPM code. | |||
Poster TUPP037 [1.102 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP037 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 11 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP038 | Spatial Resolution of an X-ray Pinhole Camera using a Multi-layer Monochromator | photon, emittance, synchrotron, feedback | 417 |
|
|||
X-ray pinhole cameras are widely used for beam emittance monitoring at synchrotron light sources. Due to the reduction in beam emittance expected for the many fourth generation machine upgrades, the spatial resolution of the pinhole camera must be improved accordingly. It is well known that there are many contributions to the point spread function. However, a significant contribution arises from diffraction by the pinhole aperture. Given that diffraction is dependent on the spectral distribution of the incident synchrotron radiation, the spatial resolution can be improved by using a monochromatic beam. For optimal performance, the photon energy should be matched to the pinhole aperture size. Here we investigate the spatial resolution of the pinhole camera as a function of photon energy using a multi-layer monochromator. | |||
Poster TUPP038 [0.617 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP038 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
TUPP047 | Ionization Profile Monitor Design and Experiments in HIRFL-CSR | electron, experiment, heavy-ion, storage-ring | 444 |
|
|||
Funding: Supported by the National Natural Science Foundation of China (Nos. 11805250 To meet the needs of real-time profile monitoring, injection match optimization, transverse cooling mechanism research in Cooling Storage Ring of Heavy Ion Research Facility of Lanzhou (HIRFL-CSR), and the profile measurement of future intense facilities like High Intensity Heavy-ion Accelerator Facility (HIAF) and China Initiative Accelerator Driven System (CiADS) in Huizhou China, some IPM research and experiments has been proceed since 2013. In 2016, the first IPM was developed with MCPs, phosphor screen and camera acquisition system for vertical profile monitoring in HIRFL-CSRm. Then another horizontal IPM with new framework and less field distortion was also deployed in CSRm at 2018 summer. Besides, two more IPMs will be installed in HIRFL-CSRe during next summer maintenance. This paper mainly presents the horizontal IPM design concerns, HV settings influence, some experiment anomalies, as well as experiments for transverse electron cooling and normal operation mode orbit variation at HIRFL-CSR in December 2018. |
|||
Poster TUPP047 [1.532 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP047 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEAO01 | Technological Review of Beam Position Button Design and Manufacture | resonance, FEL, electron, electronics | 448 |
|
|||
A workshop in May 2019, hosted by DLS (UK), reviewed both the design and the manufacturing aspects of beam position monitor (BPM) pick-up buttons with an integrated UHV feedthrough and coaxial connector. The UHV feedthrough technology (e.g. ceramic brazing vs glass-sealing), the limits on mechanical tolerances, reproducibility and material choices for high reliability were examined by more than 20 diagnostics users of these devices and a number of reputed manufacturers. Calibration techniques and tools and methods for inspection & testing were also assessed. This talk will present the outcome & conclusions of this workshop and identify challenges and opportunities for future BPM manufacture. | |||
Slides WEAO01 [1.824 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEAO01 | ||
About • | paper received ※ 05 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEAO04 | Beam Measurements at the CERN SPS Using Interferometric Electro-Optic Pickups | pick-up, laser, proton, luminosity | 457 |
|
|||
Funding: Work supported by UK STFC grants ST/N001583/1, JAI at Royal Holloway University of London and CERN. Since 2016 a prototype electro-optic pickup has been installed on the SPS as part of the ongoing development of a high bandwidth electro-optic beam position monitor for the High Luminosity LHC. Following the success of initial beam signal observations with the prototype, improvements of the sensitivity and stability of the pickup have become the main focus of the project. A new concept has been developed which uses an interferometric technique to measure the image field of a passing bunch. One arm of an interferometer passes through an electro-optic lithium niobate crystal, embedded in a pickup, whereas the other arm bypasses. The recombination after the pickup results in an interference pattern that changes as a bunch passes by, due to the electro-optic response of the crystal to the image field. This technique enhances the sensitivity to the field and improves control of the working point. Results from high intensity beams at the SPS are presented. These include a comparison between two different interferometric configurations that were tested on different pickups with similar beam conditions. The stability is assessed by frequency scanning interferometry during beam operation. |
|||
Slides WEAO04 [52.252 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEAO04 | ||
About • | paper received ※ 10 September 2019 paper accepted ※ 12 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP001 | Study and Characterization of SPIRAL2 BPMs | linac, electron, MEBT, rfq | 499 |
|
|||
The SPIRAL2 facility currently under commissioning at GANIL in France will deliver high-intensity up to 20MeV/n and 5mA light and heavy ions beams. SPIRAL2 beams are accelerated by a Radio Frequency Quadrupole (RFQ) and a LINAC fitted with 20 supraconducting cavities. A tuning of the SPIRAL2 LINAC relies mainly on Pick-up Beam Profile Monitors (BPM). 20 BPM are mounted inside the warm sections between superconducting cavities. They serve to measure a beam transverse position to center the beam, a phase to tune cavities and an ellipticity to adjust beam optics along the LINAC. The phase and ellipticity measurements require high acquisition accuracy of the BPM signals. This paper deals with an analytical study and CST code simulations of the BPM performed in order to compute correction coefficients for the ellipticity measurements. The results of calculations were compared with experimental ones obtained with two BPMs located on a ¿diagnostic plate¿ after the RFQ . Finally, the BPM acquisition chain was carefully characterized to identify its uncertainties and to ensure that it meets initial specifications. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP001 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP010 | Design and Simulation of a Cavity BPM for HUST Proton Therapy Facility | cavity, proton, coupling, impedance | 530 |
|
|||
In proton therapy facility, non-destructive beam diagnostic devices are essential for on-line measurement during the patient treatment. To meet the clinical requirement, the beam current becomes ultra-low of the order of nano-ampere, which is a great challenge to non-destructive beam diagnostics because of the extremely low signal level. Compared with conventional non-destructive beam diagnostic devices, the cavity beam position monitor (BPM) has a high shunt impedance to get enough power levels, so a cavity BPM system is designed for HUST-PTF. It is made up of two resonant cavities called reference cavity and position cavity, respectively. Both cavities are simulated and optimized by CST Microwave Studio and Particle Studio. Finally, the electronics of cavity BPM we plan to use is shown. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP010 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 07 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP022 | A Method of Correcting the Beam Transverse Offset for the Cavity Bunch Length Monitor | cavity, dipole, free-electron-laser, impedance | 572 |
|
|||
Funding: Supported by National Key R&D Program of China (Grant No. 2016YFA0401900 and No. 2016YFA0401903) and The National Natural Science Foundation of China (Grant No. U1832169 and No. 11575181) Cavity bunch length monitor uses monopole modes excited by bunches within the cavities to measure the bunch longitudinal root mean square (rms) length. It can provide a very high accuracy and high resolution. However, when the bunch passes through the cavities with transverse offset (that is, the bunch moves off the cavity axis), the amplitude of the monopole modes will change and cannot reflect the bunch length precisely. In this paper, a method of correcting the beam transverse offset is proposed. Simulation results show that the method can reduce the error of the bunch length measurement significantly. |
|||
Poster WEPP022 [0.735 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP022 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP025 | A Transverse Deflecting Cavity Prototype for the MAX IV LINAC | linac, vacuum, polarization, gun | 575 |
|
|||
The MAX IV LINAC operates both as a full-energy injector for two electron storage rings, and as a driver for a Short Pulse Facility (SPF). There are also plans to build Soft X-ray Laser (SXL) beamlines at the end of the existing LINAC. For SPF and SXL operation, it is important to characterize beam parameters such as bunch profile, slice energy spread and slice emittance. For these measurements, two 3 m long transverse deflecting RF structures are being developed. The structures are operating at S-band, and it is possible to adjust the polarization of the deflecting fields. In order to verify the RF concept, a short 9-cell prototype was constructed. The measurements results of the prototype are presented in this paper. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP025 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP030 | Betatron Phase Advance Measurements Using the Gated Turn-by-turn Monitors at SuperKEKB | betatron, coupling, luminosity, detector | 591 |
|
|||
In the SuperKEKB commissioning Phases 2 (Feb.-Jul., 2018) and 3 (from Mar. 2019), the betatron phase advances between adjacent beam position monitors have been measured using a total of 138 gated turn-by-turn monitors. A fast RF gating of the monitors enables turn-by-turn beam position detections by focusing only on an artificially-excited non-colliding bunch, while leaving colliding bunches unaffected. Betatron phase advances measured by the gated turn-by-turn monitors and accordingly obtained betatron functions were consistent with the closed orbit measurements. High signal-to-noise ratio were achieved by advanced signal extraction methods such as NAFF, SVD, and independent component analysis. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP030 | ||
About • | paper received ※ 03 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP032 | Beam Based Alignment of Elements and Source at the ESS Low Energy Beam Transport Line | solenoid, LEBT, MMI, alignment | 600 |
|
|||
The European Spallation Source (ESS), currently under construction in Lund, Sweden, will be the world’s most powerful linear accelerator driving a neutron spallation source, with an average power of 5 MW at 2.0 GeV. The first protons were accelerated at the ESS site during the commissioning of the ion source and low energy beam transport (LEBT), that started in September 2018 and ran until July 2019. Misalignments of the elements in the LEBT can have a strong impact on the final current transmission of the low energy part. In this paper, we present a way to isolate and measure tilts of the elements and the initial centroid divergence of the source. We also present initial test measurements for the ESS LEBT and discuss how to extend the method to other facilities. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP032 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
WEPP040 | Optimization of Antiproton Capture for Antihydrogen Creation in the ALPHA Experiment | proton, antiproton, experiment, electron | 637 |
|
|||
At the ALPHA Experiment at CERN, thin foils of material are used to slow down and trap antiprotons in a Penning trap, where they can be used for antihydrogen creation and measurements. Historically, over 99% of antiprotons are lost during the capture process as a result of the 5.3 MeV initial kinetic energy of the beam delivered by the Antiproton Decelerator. This places a limit early on in the achievable number of antihydrogen. ELENA is a new storage ring coming online which will lower this initial kinetic energy of the beam to 100 keV, requiring experiments to update their infrastructure. We present Monte Carlo and particle tracking simulation results for the optimization of the new degrading foil material, thickness, and location in the ALPHA catching Penning trap. From these results, we expect an upper capture efficiency of roughly 50 %. We further propose techniques for manipulating, detecting and extracting on the anticipated larger-numbered antiproton plasmas. These methods and associated hardware developments will allow performing antiproton experiments with significantly higher efficiency in ALPHA and other similar antiproton-based experiments. | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP040 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 11 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
THAO04 | Transverse Emittance Measurement using Undulator High Harmonics for Diffraction Limited Storage Rings | undulator, emittance, radiation, electron | 674 |
|
|||
Funding: This research used resources of the Advanced Photon Source, operated for the U.S Department of Energy Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. A particular challenge for diagnostics in diffraction limited storage ring light sources is the measurement of electron beam transverse emittances. In the present work, we present measurements and simulations of vertical electron beam emittance using high harmonics from an electromagnetic undulator in the present Advanced Photon Source storage ring. Based on these results, using simulation we motivate an undulator-based horizontal and vertical transverse emittance monitor for diffraction limited storage rings, using the Advanced Photon Source Upgrade as an example. |
|||
Slides THAO04 [2.655 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-THAO04 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
THBO01 | Machine Learning-Based Longitudinal Phase Space Prediction of Two-Bunch Operation at FACET-II | diagnostics, operation, experiment, linac | 679 |
|
|||
Funding: This work was supported by the U.S. Department of Energy under Contract No. DEAC02-76SF00515 We report on the application of machine learning (ML) methods for predicting the longitudinal phase space (LPS) distribution of particle accelerators. Our approach consists of training a ML-based virtual diagnostic to predict the LPS using only nondestructive linac and e-beam measurements as inputs. We validate this approach with a simulation study for the FACET-II linac and with an experimental demonstration conducted at LCLS. At LCLS, the e-beam LPS images are obtained with a transverse deflecting cavity and used as training data for our ML model. In both the FACET-II and LCLS cases we find good agreement between the predicted and simulated/measured LPS profiles, an important step towards showing the feasibility of implementing such a virtual diagnostic on particle accelerators in the future. References: * C. Emma, A. Edelen, M. J. Hogan, B. O¿Shea, G. White, and V. Yakimenko., PRAB 21, 112802 (2018) ** A. Scheinker, A. Edelen, D. Bohler, C. Emma, A. Lutman., PRL 121, 044801 (2018) |
|||
Slides THBO01 [9.917 MB] | |||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-THBO01 | ||
About • | paper received ※ 04 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019 | ||
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||