Studies of Beam Loss Monitors at the China Spallation Neutron Source
180
T. Yang, W.L. Huang, F. Li, X.J. Nie, R.Y. Qiu, J.L. Sun, A.X. Wang, T.G. Xu, Zh.H. Xu
IHEP CSNS, Guangdong Province, People’s Republic of China
M.Y. Liu, M. Meng, J.M. Tian, L. Zeng
IHEP, Beijing, People’s Republic of China
Funding:National Natural Science Foundation of China (Grants No. 11575219, No. 11705215, and No. 11805220). Beam loss detection is essential for the machine protection and the fine tuning of the accelerator to reduce the induced radioactivity. The beam loss monitors (BLM) at the China Spallation Neutron Source (CSNS) are mainly divided into the following types: the coaxial cylindrical ionization chamber (IC) filled with Ar/N2 gas mixture, Xe, BF3 gas, and the scintillator with photomul-tipliers, among which the Ar/N2 IC is the main type. In the low-energy section of the linac (beam energy <20 MeV), the BF3 BLMs enclosed by a high-density poly-ethylene (HDPE) moderator are utilized to detect the beam losses. The Monte Carlo program FLUKA is employed to perform the relevant simulations. This paper presents the summary of the beamloss detection for the CSNS BLM system. Experimental studies and Monte Carlo simulations for beam loss monitors Tao Yang, et al. Phys. Rev. Accel. Beams 24, 032804 (2021)
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C. Ozkan Loch, R. Ischebeck, A.M.M. Stampfli
PSI, Villigen PSI, Switzerland
For several years, the SLS storage ring was not equipped with any loss monitors; hence, any understanding of the operational losses, accidental losses, or manual beam dumps was missing. Initially, a long quartz fiber (350 m) was installed around the ring to locate losses, and read out with a photomultiplier tube. With the long fiber, we garnered some understanding yet, it was not easy to locate the position of the losses. Hence, we opted for scintillator based fiber loss monitors, installed in certain location. All the fibers are read out together with a single CMOS based 2.3MP camera. A device was built for 28 channels. 10 fibers were connected and are located in the injection kicker in the booster to ring transfer line and three Arcs storage ring. With these loss monitors, we were able to detect and locate the position of losses due to injection and sudden beam dumps or losses. In this poster, we will introduce the concept and the components of this monitor, and present the data processing algorithm that allow us to locate and track the losses in the SLS storage ring.
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Design and Numerical Investigations of Scintillation Beam Loss Monitor for PolFEL
281
R. Kwiatkowski, M. Krakówiak, S. Mianowski, R. Nietubyc, J. Szewiński
NCBJ, Świerk/Otwock, Poland
A.I. Wawrzyniak
NSRC SOLARIS, Kraków, Poland
Funding:Work supported by Smart Growth Operational Programme, Measure 4.2: Development of modern research infrastructure of the science sector The Beam Loss Monitor (BLM) system is used mainly for machine protection and is particularly important in the case of high energy density of accelerated beam, when such a beam could lead to serious damages in the case of uncontrolled loss. The Polish Free Electron Laser, PolFEL, will be equipped with linear superconducting accelerator operating in continuous wave regime. The maximum energies of electrons will be equal to about 180 MeV, or 270 MeV for 2nd phase of operation. The beam charge, pulse width and repetition rate will be in the range of 100-250 pC, 0.1-10 ps and 50 kHz respectfully. Operational parameters of PolFEL linear accelerator induced needs to install and operate the BLM system. One of the type of BLMs is based on the scintillation detectors. Such a system is characterized by, e.g.: high sensitivity, fast response, broad gain range and relatively low cost. Another important feature of such setup is the option of checking the operation of detector by using the integrated LED. The BLM concept for PolFEL is based on several scintillation probes placed along the linear accelerator. The paper reports on numerical investigation of electron and X-ray radiation induced during fast electron losses. We also present design of BLM detectors and results of first tests of a prototype on the linear electron accelerator at Solaris research centre.
The Beam Loss Monitoring System after LHC Injectors Upgrade at CERN
285
M. Saccani, E. Calvo Giraldo, W. Viganò, C. Zamantzas
CERN, Geneva, Switzerland
The LHC Injector Upgrade project aims to increase the brightness of the beams available and improve the efficiency of the whole accelerator chain. The Beam Loss Monitoring (BLM) system is a key element of CERN’s accelerator instrumentation for beam optimisation and machine protection by producing continuous and reliable beam loss measurements while ensuring safe operation. The new BLM system for the LHC Injectors aimed to provide faster measures with a higher dynamic range, to install more detectors along the beamlines and to give the operator more flexible use. A review will be given on the versatility provided by the system to cover requirements from various accelerators and their transfer lines, focusing on the measurements and the operational scenarios.
Beam Loss Signal Calibration for the LHC Diamond Detectors During Run 2
290
S. Morales Vigo, E. Calvo Giraldo, E. Effinger, B. Salvachua, C. Zamantzas
CERN, Geneva, Switzerland
C.P. Welsch, J. Wolfenden
The University of Liverpool, Liverpool, United Kingdom
Chemical Vapour Deposition (CVD) diamond detectors can be used as fast beam loss monitors in particle accelerators. In the Large Hadron Collider (LHC) at CERN, they are installed in the betatron collimation region, a high-radiation environment. In addition to their high-radiation tolerance, their main advantage is a time resolution of 1 ns which makes possible not only turn-by-turn, but also bunch-by-bunch loss measurements. An analysis of the LHC diamond beam loss monitor signals recorded during the last months of Run 2 (September 2018-November 2018) is presented with the aim of obtaining a signal-to-beam loss calibration.
Methodology, Characterisation and Results from the Prototype Beam Loss Monitoring ASIC at CERN
294
F. Martina, L. Giangrande, J. Kaplon, P.V. Leitao, C. Zamantzas
CERN, Geneva 23, Switzerland
J.W. Bradley, F. Martina, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom
F. Martina, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
The characterisation of novel beam loss monitoring front-end converters, based on radiation-hardened application-specific integrated circuits (ASIC), is undergoing at CERN. An effective performance analysis of the newly developed ASICs plays a key role in their candidacy for the future installation in the HL-LHC complex. This work introduces the latest test-bed architecture, used to characterise such a device, together with the variety of audits involved. Special focus is given on the verification methodology of data acquisition and measurements, in order to allow a detailed study of the conversion capabilities, the evaluation of the device resolution and the linearity response. Finally, the first results of post-irradiation measurements are also reported.
New Applications and Studies with the ESRF Beam Loss Monitoring at Injection
299
E. Buratin, N. Benoist, N. Carmignani, F. Ewald, J.L. Pons, K.B. Scheidt
ESRF, Grenoble, France
More than one year after the commissioning of the ESRF’s new Extremely Brilliant Source (EBS), the Beam Loss Detectors (BLDs) are continuing to be used for extensive applications and studies, notably at injection. A total of 144 BLDs and 36 associated Libera Beam Loss Monitors (BLMs) are distributed in the EBS ring and the Booster. These BLDs allow to measure slow losses during user-mode operation and fast losses at injection, with a sub-orbit-turn time resolution. In this paper these fast beam loss dynamics are presented at injection for different lattice parameters, collimator-settings and beam conditions. We will also show the excellent correlation with results obtained from the injection efficiency diagnostic and the bunch length acquired with the Streak Camera.
Application of the CORIS360 Gamma Ray Imager at a Light Source
303
Y.E. Tan
AS - ANSTO, Clayton, Australia
D. Boardman, L. Chartier, M.C. Guenette, J.K. Ilter, G. Watt
ANSTO, Menai, New South Wales, Australia
The CORIS360 is a gamma-ray imager developed at Australian Nuclear Science and Technology (ANSTO) for identifying and localising sources of radiation typically from gamma emitting radionuclides. The low EMI and low noise power supply features of the imaging technology have enabled it to have a low energy detection threshold and to detect photons as low as 20 keV. This report shall present the initial measurements performed at the Australian Synchrotron, in the storage ring and beamlines, where the imager is able to detect radiation from all sources of synchrotron radiation (dipole, wiggler and undulator). The radiation imaging results from the injection system and scrapers (to dump the stored beam) will be discussed. Future developments for imaging in pulsed radiation environments and time varying environments will also be discussed.
Machine-Learning Based Temperature Prediction for Beam-Interceptive Devices in the ESS Linac
306
E.M. Donegani
ESS, Lund, Sweden
’Where there is great power [density], there is great responsibility*.’ The concept holds true especially for beam-intercepting devices for the ESS linac commissioning. In particular, beam-intercepting devices will be subject to challenging beam power densities, stemming from proton energies up to 2 GeV, beam currents up to 62.5 mA, pulses up to few milliseconds long, and repetition rates up to 14 Hz. Dedicated Monte Carlo simulations and thermo-mechanical calculations are necessarily part of the design workflow, but they are too time-consuming when in need of rapid estimates of temperature trends. In this contribution, the usefulness of a Recurrent Neural Network (RNN) was explored in order to forecast (in few minutes) the bulk temperature of beam-interceptive devices. The RNN was trained with the already existing database of MCNPX/ANSYS results from design studies. The feasibility of the method will be exemplified in the case of the Insertable Beam Stop within the Spoke section of the ESS linac. *Winston Churchill, 1906
