Cover Image

Decommissioning and Post-Irradiation Examination of the LHC Beam Dumps

Fuente: arXiv

Saved in:

Bibliographic Details
Main Authors:	Solieri, N., Lund, A., Bernardes, A. -P., Buonocore, L. R., Cherif, A., De Man, S., Di Castro, M., Di Giovannantonio, S., Dumont, G., El-Idrissi, S., Farina, E., Grenier, D., Grenier-Boley, E., Himmerlich, M., Infantino, A., Lechner, A., Mouret, R., Pazem, D., Perez-Fontenla, A. T., Romagnoli, E., Sgobba, S., Tromel, C., Almagro, C. Veiga, Calviani, M.
Format:	Preprint
Published:	2025
Subjects:	Accelerator Physics
Online Access:	Acceder al recurso
Tags:	Add Tag No Tags, Be the first to tag this record!

_version_	1866908531194593280
author	Solieri, N. Lund, A. Bernardes, A. -P. Buonocore, L. R. Cherif, A. De Man, S. Di Castro, M. Di Giovannantonio, S. Dumont, G. El-Idrissi, S. Farina, E. Grenier, D. Grenier-Boley, E. Himmerlich, M. Infantino, A. Lechner, A. Mouret, R. Pazem, D. Perez-Fontenla, A. T. Romagnoli, E. Sgobba, S. Tromel, C. Almagro, C. Veiga Calviani, M.
author_facet	Solieri, N. Lund, A. Bernardes, A. -P. Buonocore, L. R. Cherif, A. De Man, S. Di Castro, M. Di Giovannantonio, S. Dumont, G. El-Idrissi, S. Farina, E. Grenier, D. Grenier-Boley, E. Himmerlich, M. Infantino, A. Lechner, A. Mouret, R. Pazem, D. Perez-Fontenla, A. T. Romagnoli, E. Sgobba, S. Tromel, C. Almagro, C. Veiga Calviani, M.
contents	The LHC beam dumps are responsible for the safe absorption of the Large Hadron Collider (LHC) particle beams. In 2018, the two 6.4-tonne beam dumps that had been in operation since the LHC's startup in 2008 were removed and replaced with upgraded versions. Endoscopic inspections of these beam dumps and experimental high-intensity proton-beam irradiation of material samples raised concerns about the structural integrity of the carbon-based materials in their cores. It was therefore decided to undertake an accelerated project of dismantling and post-irradiation examination of the removed dumps as part of a wider program of work to ensure the safe operation of the LHC beam dumps in the coming years. This paper describes the decommissioning process for the two beam dumps carried out at CERN between 2021 and 2023, covering the preparatory studies, practical challenges encountered, and solutions implemented. It details the establishment of an operational framework, including the preparation of the working environment, the development of a method for cutting the irradiated 12-mm-thick duplex stainless-steel vessel, and the cut sequencing. Additionally, the paper presents the findings derived from the post-irradiation examination of the different carbon-based core materials subjected to deposited energy densities up to 1.5 kJ/g. The extruded graphite plates within the vessel exhibited a cracking pattern, which was likely due to the dynamic response of the device upon beam impact, and their retaining rings were found to be displaced. Despite minor signs of surface deterioration, the expanded graphite sheets were intact, and the isostatic graphite blocks showed no evidence of material degradation.
format	Preprint
id	arxiv_https___arxiv_org_abs_2505_04235
institution	arXiv
publishDate	2025
record_format	arxiv
spellingShingle	Decommissioning and Post-Irradiation Examination of the LHC Beam Dumps Solieri, N. Lund, A. Bernardes, A. -P. Buonocore, L. R. Cherif, A. De Man, S. Di Castro, M. Di Giovannantonio, S. Dumont, G. El-Idrissi, S. Farina, E. Grenier, D. Grenier-Boley, E. Himmerlich, M. Infantino, A. Lechner, A. Mouret, R. Pazem, D. Perez-Fontenla, A. T. Romagnoli, E. Sgobba, S. Tromel, C. Almagro, C. Veiga Calviani, M. Accelerator Physics The LHC beam dumps are responsible for the safe absorption of the Large Hadron Collider (LHC) particle beams. In 2018, the two 6.4-tonne beam dumps that had been in operation since the LHC's startup in 2008 were removed and replaced with upgraded versions. Endoscopic inspections of these beam dumps and experimental high-intensity proton-beam irradiation of material samples raised concerns about the structural integrity of the carbon-based materials in their cores. It was therefore decided to undertake an accelerated project of dismantling and post-irradiation examination of the removed dumps as part of a wider program of work to ensure the safe operation of the LHC beam dumps in the coming years. This paper describes the decommissioning process for the two beam dumps carried out at CERN between 2021 and 2023, covering the preparatory studies, practical challenges encountered, and solutions implemented. It details the establishment of an operational framework, including the preparation of the working environment, the development of a method for cutting the irradiated 12-mm-thick duplex stainless-steel vessel, and the cut sequencing. Additionally, the paper presents the findings derived from the post-irradiation examination of the different carbon-based core materials subjected to deposited energy densities up to 1.5 kJ/g. The extruded graphite plates within the vessel exhibited a cracking pattern, which was likely due to the dynamic response of the device upon beam impact, and their retaining rings were found to be displaced. Despite minor signs of surface deterioration, the expanded graphite sheets were intact, and the isostatic graphite blocks showed no evidence of material degradation.
title	Decommissioning and Post-Irradiation Examination of the LHC Beam Dumps
topic	Accelerator Physics
url	https://arxiv.org/abs/2505.04235