HB2023 - Table of Session: WEC2C (Contributed Presentations WG E)

Paper	Title	Page
WEC2C1	Evaluation of Power Deposition in HL-LHC with Crystal-assisted Heavy Ion Collimation	236
	V. Rodin, R. Bruce, R. Cai, M. D’Andrea, L.S. Esposito, A. Lechner, J.B. Potoine, S. Redaelli, J. Schoofs CERN, Meyrin, Switzerland R. Cai EPFL, Lausanne, Switzerland J.B. Potoine IES, Montpellier, France
	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.
	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)

WEC2C2	Two-Dimensional Temperature Measurements of Nanocrystalline Diamond Stripper Foils at High Intensity Hydrogen Ion Beams at SNS
	A.R. Oguz, W. Blokland ORNL, Oak Ridge, Tennessee, USA N.J. Evans ORNL RAD, Oak Ridge, Tennessee, USA
	Funding: This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. We propose and demonstrate a time-resolved, two-dimensional temperature monitoring technique for nanocrystalline diamond stripper foils exposed to high-intensity H^- beams at the Spallation Neutron Source (SNS) accumulator ring. The technique utilizes a two-color imaging pyrometer in the shortwave infrared (SWIR) spectral band to measure thermal radiation from stripper foils located 40 meters away from the measurement site. This work presents a unique optical design, optical calibration of the system using a high-temperature blackbody source, preliminary temperature measurement results from two stripper foils (new and used) under various H^- production beam conditions with average powers up to 1.7~MW and energy of 1.0~GeV. The technique we developed could be utilized to understand the thermal behavior of charge strippers under high-intensity particle beams and may lead to significant improvements in their lifetime in high-intensity particle accelerator.
	Slides WEC2C2 [7.747 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Evaluation of Power Deposition in HL-LHC with Crystal-assisted Heavy Ion Collimation

236

V. Rodin, R. Bruce, R. Cai, M. D’Andrea, L.S. Esposito, A. Lechner, J.B. Potoine, S. Redaelli, J. Schoofs
CERN, Meyrin, Switzerland
R. Cai
EPFL, Lausanne, Switzerland
J.B. Potoine
IES, Montpellier, France

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.

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)

WEC2C2

Two-Dimensional Temperature Measurements of Nanocrystalline Diamond Stripper Foils at High Intensity Hydrogen Ion Beams at SNS

A.R. Oguz, W. Blokland
ORNL, Oak Ridge, Tennessee, USA
N.J. Evans
ORNL RAD, Oak Ridge, Tennessee, USA

Funding: This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.
We propose and demonstrate a time-resolved, two-dimensional temperature monitoring technique for nanocrystalline diamond stripper foils exposed to high-intensity H^- beams at the Spallation Neutron Source (SNS) accumulator ring. The technique utilizes a two-color imaging pyrometer in the shortwave infrared (SWIR) spectral band to measure thermal radiation from stripper foils located 40 meters away from the measurement site. This work presents a unique optical design, optical calibration of the system using a high-temperature blackbody source, preliminary temperature measurement results from two stripper foils (new and used) under various H^- production beam conditions with average powers up to 1.7~MW and energy of 1.0~GeV. The technique we developed could be utilized to understand the thermal behavior of charge strippers under high-intensity particle beams and may lead to significant improvements in their lifetime in high-intensity particle accelerator.

Slides WEC2C2 [7.747 MB]

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)