KEK, Ibaraki, Japan
KEK, Ibaraki, Japan
KEK, Ibaraki, Japan
TH2C02
KEK, Ibaraki, Japan
| Paper | Title | Page |
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| TU1I01 | Beam Instrumentation Challenges for High-Energy and Low-Emittance Beam at SuperKEKB | 131 |
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| The SuperKEKB electron-positron collider, which started the commissioning in February 2016, is a luminosity frontier machine for the search for new physics. In this presentation, we review the main challenges we face for the high-energy and low-emittance beam at SuperKEKB, fast and low-noise beam-orbit feedback system, X-ray beam-profile monitors for measurements for the beam size of ¿10 um, novel diamond mirrors with extremely high thermal conductivity for extracting synchrotron radiation, and various type’s beam loss diagnostics for the identification or possibly early detection of sudden beam losses. This presentation includes future directions of the R&D–-X-ray interferometry for micron-level beam size measurements and fast optics measurements with the gated turn-by-turn BPMs–-towards next-generation light source facilities and high-energy colliders. | ||
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Slides TU1I01 [5.927 MB] | |
| DOI • | reference for this paper ※ doi:10.18429/JACoW-IBIC2023-TU1I01 | |
| About • | Received ※ 06 September 2023 — Revised ※ 13 September 2023 — Accepted ※ 14 September 2023 — Issue date ※ 27 September 2023 | |
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| TUP002 | Development of Bunch Position Monitors to Observe Sudden Beam Loss of SuperKEKB Rings | 179 |
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| In the SuperKEKB rings, we have encountered extremely-fast beam losses occurring primarily within one to two turns in some parts of the bunch train. Such ¿sudden beam loss¿ induced severe failure in the vertical collimator heads, quenches on the superconducting final quadrupoles, and damage on the Belle II detector in some cases. Thus it is essential to investigate the cause and take countermeasures. This paper presents the phenomena clarified by the bunch current and position monitor of the bunch feedback system. The upgrade plan for the existing monitor, and recently developed simple monitors installed in the suspected area is also introduced. | ||
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Poster TUP002 [0.727 MB] | |
| DOI • | reference for this paper ※ doi:10.18429/JACoW-IBIC2023-TUP002 | |
| About • | Received ※ 06 September 2023 — Revised ※ 08 September 2023 — Accepted ※ 13 September 2023 — Issue date ※ 27 September 2023 | |
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEP005 | Effect of Incoherent Depth of Field for Bean Halo Measurement with the Coronagraph in SuperKEKB | 335 |
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| The incoherent depth-of-field due to the instantaneous opening angle of dipole SR will reduce the spatial coherence of SR in horizontal direction in the beam size measurement by using interferometry. This reduction of spatial coherence is due to both of apparent change of the beam profile due to field depth and intensity distribution in the aperture. In the case of beam profile measurement by imaging system, observed beam profile will deform and produce a beam tail in asymmetric manner by this effect. This apparent change of beam profile, especially extra beam tail in one side has certain influence for beam halo measurement using the coronagraph, because it has a large dynamic range of 6 order magnitude. Since the magnitude of asymmetric tail is proportional to bending radius, this effect is larger in large high energy physics machine which has a long bending radius. This effect is theoretically studied and compare with coronagraph measurement result of beam halo in the SuperKEKB. As a conclusion, this effect is very small and not observable in the coronagraph measurement at SuperKEKB. | ||
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Poster WEP005 [0.570 MB] | |
| DOI • | reference for this paper ※ doi:10.18429/JACoW-IBIC2023-WEP005 | |
| About • | Received ※ 05 September 2023 — Revised ※ 09 September 2023 — Accepted ※ 13 September 2023 — Issue date ※ 21 September 2023 | |
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TH2C02 |
Machine Learning-Assisted Beam Operation at SuperKEKB and Linac at KEK | |
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| Hundreds to thousands of tuning parameters must be optimized for each operating condition to obtain the best performance from an accelerator. In the past, experts made decisions based on their experience on which tuning parameters contributed the most to the performance and adjusted them sequentially. On the other hand, accelerator tuning approaches based on machine learning, which has become much easier to handle, have been studied intensively in recent years. We have been developing a beam-tuning tool based on Bayesian optimization for boosting the SuperKEKB accelerator. In this presentation, we will report on the latest status of the beam test of the positron-beam-yield maximization and dispersion tuning at the KEK injector as the first development step. | ||
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Slides TH2C02 [2.902 MB] | |
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |