| Paper | Title | Other Keywords | Page |
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| WEC2C1 | Evaluation of Power Deposition in HL-LHC with Crystal-assisted Heavy Ion Collimation | collimation, operation, simulation, betatron | 236 |
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The future LHC heavy-ion program, utilizing 208Pb82+ beams at up to 7 Z TeV, is anticipated to operate with substantial intensity upgrade. During periods of short beam lifetime, a potential performance limitation may arise from secondary ions produced by electromagnetic dissociation and hadronic fragmentation in the collimators of the betatron cleaning insertion. These off-rigidity fragments risk quenching superconducting magnets when they are lost in the dispersion suppressor. To address this concern, an alternative collimation scheme will be introduced for forthcoming heavy ion runs, employing bent channeling crystals as primary collimators. In this contribution, we detail a thorough study of power deposition levels in superconducting magnets through FLUKA shower simulations in the crystal-based collimation system. The study focuses on the downstream dispersion suppressor regions of the betatron cleaning insertion, where the quench risk is the highest. Based on this work, we quantify the expected quench margin in future runs with 208Pb82+ beams, providing crucial insights for the successful execution of the upgraded heavy-ion program at the HL-LHC.
Research supported by the HL-LHC project. |
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Slides WEC2C1 [3.105 MB] | ||
| DOI • | reference for this paper ※ doi:10.18429/JACoW-HB2023-WEC2C1 | ||
| About • | Received ※ 24 November 2023 — Revised ※ 25 November 2023 — Accepted ※ 29 November 2023 — Issued ※ 16 January 2024 | ||
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| WEA4I1 | Development of Non-Destructive Beam Envelope Measurements Using BPMs for Low Beta Heavy Ion Beams in SRF Cavities | simulation, cavity, emittance, quadrupole | 284 |
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Accurate measurement and control of the beam envelope are crucial issues, particularly in high-power accelerator facilities. However, the use of destructive monitors is limited to low-intensity beams. Furthermore, in the case of beam transport between superconducting cavities, these destructive monitors are avoided to prevent the generation of dust particles and outgassing. In the Superconducting RIKEN LINAC, or SRILAC [1], we utilize 8 non-destructive Beam Energy Position Monitors (BEPMs)[2] to measure beam positions and energies. Recently we are developing a method for estimating the beam envelope by combining the quadrupole moments from BEPMs, which consist of four cosine-shape electrodes, with transfer matrix[3]. While this method has been applied to electron and proton beams, it has not been practically demonstrated for heavy ion beams in beta ¿0.1 regions. By combining BEPM simulations, we are making progress toward the reproduction of experimental results, overcoming specific issues associated with low beta. This development will present the possibility of a new method for beam envelope measurement in LEBT and MEBT, especially for hadron beam facilities.
[1] K. Yamada et al., in Proc. SRF2021, paper MOOFAV01(2021). [2] T. Watanabe et al., in Proc. IBIC2020, paper FRAO04 (2020). [3] R. H. Miller et al., in Proc. HEAC¿83, pp. 603¿605 (1983). |
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Slides WEA4I1 [10.867 MB] | ||
| DOI • | reference for this paper ※ doi:10.18429/JACoW-HB2023-WEA4I1 | ||
| About • | Received ※ 12 October 2023 — Revised ※ 13 October 2023 — Accepted ※ 18 October 2023 — Issued ※ 01 November 2023 | ||
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| THA2C4 | Alternating Phase Focusing Under Influence of Space Charge Defocusing | linac, focusing, software, cavity | 377 |
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| Alternating phase focusing (APF) recently emerged as a promising beam dynamics concept for accelerating bunched proton or ion beams in drift tube linear accelerators, eliminating the need for additional transverse and longitudinal focusing lenses. The performance of APF systems, similar to radio frequency quadrupoles, heavily relies on the employed focusing lattice, including the particle synchronous phase in each gap, as well as various hyperparameters such as the number of gaps, the focusing gradient, and the required beam acceptance. However, to fully utilize the cost advantages and mechanical simplicity of APF drift tube linacs, specialized software tools are necessary to streamline the accelerator development process. After successful developement of the HELIAC-APF-IH-DTL for low current and continuous wave duty cycle, this paper presents the design concepts for APF cavities tailored for high-current applications, aiming to facilitate the design and implementation of APF-based accelerators. | |||
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Slides THA2C4 [4.986 MB] | ||
| DOI • | reference for this paper ※ doi:10.18429/JACoW-HB2023-THA2C4 | ||
| About • | Received ※ 06 October 2023 — Revised ※ 08 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 18 October 2023 | ||
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||