HB2023 - List of Authors (Cai, R.)

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)

THBP49	Collimation of 400 MJ Beams at the LHC: The First Step Towards the HL-LHC Era	603
	S. Redaelli, A. Abramov, D.B. Baillard, R. Bruce, R. Cai, F. Carra, M. D’Andrea, M. Di Castro, L. Giacomel, P.D. Hermes, B. Lindström, D. Mirarchi, N. Mounet, F.-X. Nuiry, A. Perillo Marcone, F.F. Van der Veken CERN, Meyrin, Switzerland R. Cai EPFL, Lausanne, Switzerland A. Vella University of Malta, Information and Communication Technology, Msida, Malta
	Funding: Work supported by the HL-LHC project. An important upgrade programme is planned for the collimation system of the CERN Large Hadron Collider (LHC) in order to meet the challenges of the upcoming High-Luminosity LHC (HL-LHC) project. A first stage of the HL-LHC upgrade was already deployed during the last LHC Long Shutdown, offering important improvements of the collimation cleaning, a significant reduction of the impedance contribution and better cleaning of collisional debris, in particular for ion-ion collisions. This upgrade provides a critical opportunity to explore the LHC intensity limits during the LHC Run 3 and can provide crucial feedback to refine upgrade plans and operational scenarios in the HL-LHC era. This paper describes the performance of the upgraded LHC collimation system that has already enabled stored-beam energies larger than 400 MJ at the unprecedented beam energy of 6.8 TeV, and reviews further upgrade plans envisaged to reach 700 MJ beams at the HL-LHC.
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP49
About •	Received ※ 03 October 2023 — Revised ※ 08 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 10 October 2023
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)

THBP49

Collimation of 400 MJ Beams at the LHC: The First Step Towards the HL-LHC Era

603

S. Redaelli, A. Abramov, D.B. Baillard, R. Bruce, R. Cai, F. Carra, M. D’Andrea, M. Di Castro, L. Giacomel, P.D. Hermes, B. Lindström, D. Mirarchi, N. Mounet, F.-X. Nuiry, A. Perillo Marcone, F.F. Van der Veken
CERN, Meyrin, Switzerland
R. Cai
EPFL, Lausanne, Switzerland
A. Vella
University of Malta, Information and Communication Technology, Msida, Malta

Funding: Work supported by the HL-LHC project.
An important upgrade programme is planned for the collimation system of the CERN Large Hadron Collider (LHC) in order to meet the challenges of the upcoming High-Luminosity LHC (HL-LHC) project. A first stage of the HL-LHC upgrade was already deployed during the last LHC Long Shutdown, offering important improvements of the collimation cleaning, a significant reduction of the impedance contribution and better cleaning of collisional debris, in particular for ion-ion collisions. This upgrade provides a critical opportunity to explore the LHC intensity limits during the LHC Run 3 and can provide crucial feedback to refine upgrade plans and operational scenarios in the HL-LHC era. This paper describes the performance of the upgraded LHC collimation system that has already enabled stored-beam energies larger than 400 MJ at the unprecedented beam energy of 6.8 TeV, and reviews further upgrade plans envisaged to reach 700 MJ beams at the HL-LHC.

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP49

About •

Received ※ 03 October 2023 — Revised ※ 08 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 10 October 2023

Cite •

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