IPAC2022 - Classification: MC4: Hadron Accelerators / A04: Circular Accelerators

Paper	Title	Page
MOPOST001	Performance of Automated Synchrotron Lattice Optimisation Using Genetic Algorithm	38
SUSPMF042	use link to see paper's listing under its alternate paper code
	X. Zhang, S.L. Sheehy The University of Melbourne, Melbourne, Victoria, Australia S.L. Sheehy ANSTO, Kirrawee DC New South Wales, Australia
	Funding: Work supported by Australian Government Research Training Program Scholarship Rapid advances in superconducting magnets and related accelerator technology opens many unexplored possibilities for future synchrotron designs. We present an efficient method to probe the feasible parameter space of synchrotron lattice configurations. Using this method, we can converge on a suite of optimal solutions with multiple optimisation objectives. It is a general method that can be adapted to other lattice design problems with different constraints or optimisation objectives. In this method, we tackle the lattice design problem using a multi-objective genetic algorithm. The problem is encoded by representing the components of each lattice as columns of a matrix. This new method is an improvement over the neural network based approach* in terms of computational resources. We evaluate the performance and limitations of this new method with benchmark results. *Conference Proceedings IPAC’21, 2021. DOI:10.18429/JACoW-IPAC2021-MOPAB182
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST001
About •	Received ※ 19 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST004	Beam-Based Measurement of Skew-Sextupole Errors in the CERN Proton Synchrotron	46
	S.J. Horney, A. Huschauer, E.H. Maclean CERN, Meyrin, Switzerland
	During Proton Synchrotron (PS) commissioning in 2021, large beam losses were observed when crossing the 3Qy resonance if the Beam Gas Ionization (BGI) profile monitor was enabled. This indicated the presence of a strong skew-sextupole source in this instrument. Beam-based measurements of the skew sextupole component in the BGI magnet were performed, in order to benchmark the BGI magnetic model and to provide quantitative checks of sextupole corrections determined empirically to minimize the beam-losses. In this contribution, results of the successfully performed measurements are presented, including tune feed-down, chromatic coupling and resonance driving terms.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST004
About •	Received ※ 08 June 2022 — Revised ※ 18 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 23 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST005	The HL-LHC Project Gets Ready for Its Deployment	50
	M. Zerlauth, O.S. Brüning, B. Di Girolamo, P. Fessia, C. Gaignant, H. Garcia Gavela, E.H. Maclean, M. Modena, Th. Otto, L.J. Tavian, G. Vandoni CERN, Meyrin, Switzerland
	Following the successful completion of the second long shutdown (LS2), the Large Hadron Collider (LHC) is preparing for its final operational run before the majority of the High Luminosity Upgrade (HL-LHC) will be installed during the third Long Shutdown starting in 2026. The HL-LHC upgrade will enable a further tenfold increase in integrated luminosity delivered to the ATLAS and CMS experiments, starting by an upgrade of the machine protection, collimation and shielding systems in LS2, and followed by the deployment of novel key technologies, including Nb₃Sn based insertion region magnets, cold powering by MgB₂ superconducting links and integration of Nb crab-cavities to compensate the effects of a larger crossing angle. After a period of intensive R&D and prototyping, the project is now entering the phase of industrialization and series production for all main components. In this contribution, we provide an overview of the project status and plans for deployment and performance ramp-up. Progress on the validation of key technologies, status of prototypes and series production as well as the final integration studies for the HL equipment are summarized. These are accompanied by the imminent completion of major civil engineering work and the start of infrastructure installations. Initial operational experience will be gained at the Inner Triplet (IT) String, presently in assembly at CERN’s Superconducting Magnet Test Facility, which will enable a fully integrated test of the main magnets, powering, and protection systems in the actual HL-LHC insertion configuration.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST005
About •	Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 18 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST006	Beam Commissioning and Optimisation in the CERN Proton Synchrotron After the Upgrade of the LHC Injectors	54
	A. Huschauer, M.R. Coly, D.G. Cotte, H. Damerau, M. Delrieux, J.-C. Dumont, Y. Dutheil, S.E.R. Easton, M.A. Fraser, O. Hans, G.I. Imesch, S. Joly, A. Lasheen, C.L. Lombard, R. Maillet, B. Mikulec, J.-M. Nonglaton, S. Sainz Perez, B. Salvant, R. Suykerbuyk, F. Tecker, R. Valera Teruel CERN, Meyrin, Switzerland
	The CERN LHC injector chain underwent a major upgrade during the Long Shutdown 2 (LS2) in the framework of the LHC Injectors Upgrade (LIU) project. After 2 years of installation work, the Proton Synchrotron (PS) was restarted in 2021 with the goal to achieve pre-LS2 beam quality by the end of 2021. This contribution details the main beam commissioning milestones, encountered difficulties and lessons learned. The status of the fixed-target and LHC beams will be given and improvements in terms of performance, controls and tools described.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST006
About •	Received ※ 01 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 02 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST008	Simulations of Protons to Extraction at Gγ=7.5 in the AGS Booster	62
	K. Hock, H. Huang, F. Méot BNL, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. To prepare for polarized helion collisions at the Electron Ion Collider (EIC), polarization transmission at the injectors for the Hadron Storage Ring must be studied and optimized. To this effect, an AC dipole has been installed in the AGS Booster to maximize polarization transmission of helions through several intrinsic resonances. This installation also allows polarized protons to be extracted at higher energy without polarization loss. By increasing the proton extraction energy from $Gγ$ = 4.5 to $Gγ$ = 7.5, protons will cross the $Gγ$ = 0 + ν_y$ and $Gγ = 12 - ν_y$ depolarizing vertical intrinsic resonances, the $Gγ$ = 5, 6, and 7 imperfection resonances in addition to the $Gγ$ = 3, 4 that are crossed in the present configuration, and be injected into the AGS at a higher rigidity. By simulation, it is determined that there is sufficient strength of the AC dipole to fully flip the spin spin through each of the intrinsic resonances, and there is sufficient corrector current to preserve polarization through the three additional imperfection resonances. The higher injection rigidity facilitates the horizontal and vertical tunes being placed inside the AGS spin-tune gap at injection due to a substantial improvement on the AGS admittance at injection.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST008
About •	Received ※ 06 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST009	EIC Crab Cavity Multipole Analysis and Their Effects on Dynamic Aperture	66
	Q. Wu, B.P. Xiao BNL, Upton, New York, USA S.U. De Silva ODU, Norfolk, Virginia, USA Z. Li SLAC, Menlo Park, California, USA Y. Luo Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy. Crab cavity is essential for retrieving the loss in luminosity due to the large crossing angle in the two colliding beam lines of the Electron Ion Collider (EIC). Due to the asymmetric design of the proton beam crab cavity, the fundamental mode consists of contributions from higher order multipoles. These multipole modes may change during fabrication and installation of the cavities, and therefore affect the local dynamic aperture. Thresholds for each order of the multipoles are applied to ensure dynamic aperture requirements at these crab cavities. In this paper, we analyzed the strength of the multipoles due to fabrication and installation accuracies, and set limitations to each procedure to maintain the dynamic aperture requirement.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST009
About •	Received ※ 06 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST037	Characterisation of Bunch-by-Bunch Tune Shift Effects in the CERN SPS	148
	I. Mases Solé, H. Bartosik, V. Kain, K. Paraschou, M. Schenk, C. Zannini CERN, Meyrin, Switzerland
	After the implementation of major upgrades as part of the LHC Injector Upgrade Project (LIU), the Super Proton Synchrotron (SPS) delivers high intensity bunch trains with 25 ns bunch spacing to the Large Hadron Collider (LHC) at CERN. These beams are exposed to several collective effects in the SPS, such as beam coupling impedance, space charge and electron cloud, leading to relatively large bunch-by-bunch coherent and incoherent tune shifts. Tune correction to the nominal values at injection is crucial to ensure beam stability and good beam transmission. During the beam commissioning of the SPS, measurements of the bunch-by-bunch coherent tune shifts have been conducted under different beam conditions, together with appropriate corrections of the average tunes at each injection. In this paper, we describe the methodology that has been developed to acquire bunch-by-bunch position data and to perform online computations of the coherent tune spectra of each bunch using refined Fourier transform analysis. The experimental data are compared to multiparticle tracking simulations using the SPS impedance model, in view of developing an accurate model for tune correction in the SPS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST037
About •	Received ※ 03 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022
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MOPOPT040	Summary of the Post-Long Shutdown 2 LHC Hardware Commissioning Campaign	335
	A. Apollonio, O.Ø. Andreassen, A. Antoine, T. Argyropoulos, M.C. Bastos, M. Bednarek, B. Bordini, K. Brodzinski, A. Calia, Z. Charifoulline, G.-J. Coelingh, G. D’Angelo, D. Delikaris, R. Denz, L. Fiscarelli, V. Froidbise, M.A. Galilée, J.C. Garnier, R. Gorbonosov, P. Hagen, M. Hostettler, D. Jacquet, S. Le Naour, D. Mirarchi, V. Montabonnet, B.I. Panev, T.H.B. Persson, T. Podzorny, M. Pojer, E. Ravaioli, F. Rodriguez-Mateos, A.P. Siemko, M. Solfaroli, J. Spasic, A. Stanisz, J. Steckert, R. Steerenberg, S. Sudak, H. Thiesen, E. Todesco, G. Trad, J.A. Uythoven, S. Uznanski, A.P. Verweij, J. Wenninger, G.P. Willering, D. Wollmann, S. Yammine CERN, Meyrin, Switzerland V. Vizziello INFN/LASA, Segrate (MI), Italy
	In this contribution we provide a summary of the LHC hardware commissioning campaign following the second CERN Long Shutdown (LS2), initially targeting the nominal LHC energy of 7 TeV. A summary of the test procedures and tools used for testing the LHC superconducting circuits is given, together with statistics on the successful test execution. The paper then focuses on the experience and observations during the main dipole training campaign, describing the encountered problems, the related analysis and mitigation measures, ultimately leading to the decision to reduce the energy target to 6.8 TeV. The re-commissioning of two powering sectors, following the identified problems, is discussed in detail. The paper concludes with an outlook to the future hardware commissioning campaigns, discussing the lessons learnt and possible strategies moving forward.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT040
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

MOPOST001

Performance of Automated Synchrotron Lattice Optimisation Using Genetic Algorithm

38

SUSPMF042

use link to see paper's listing under its alternate paper code

X. Zhang, S.L. Sheehy
The University of Melbourne, Melbourne, Victoria, Australia
S.L. Sheehy
ANSTO, Kirrawee DC New South Wales, Australia

Funding: Work supported by Australian Government Research Training Program Scholarship
Rapid advances in superconducting magnets and related accelerator technology opens many unexplored possibilities for future synchrotron designs. We present an efficient method to probe the feasible parameter space of synchrotron lattice configurations. Using this method, we can converge on a suite of optimal solutions with multiple optimisation objectives. It is a general method that can be adapted to other lattice design problems with different constraints or optimisation objectives. In this method, we tackle the lattice design problem using a multi-objective genetic algorithm. The problem is encoded by representing the components of each lattice as columns of a matrix. This new method is an improvement over the neural network based approach* in terms of computational resources. We evaluate the performance and limitations of this new method with benchmark results.
*Conference Proceedings IPAC’21, 2021. DOI:10.18429/JACoW-IPAC2021-MOPAB182

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST001

About •

Received ※ 19 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 17 June 2022

Cite •

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

MOPOST004

Beam-Based Measurement of Skew-Sextupole Errors in the CERN Proton Synchrotron

46

S.J. Horney, A. Huschauer, E.H. Maclean
CERN, Meyrin, Switzerland

During Proton Synchrotron (PS) commissioning in 2021, large beam losses were observed when crossing the 3Qy resonance if the Beam Gas Ionization (BGI) profile monitor was enabled. This indicated the presence of a strong skew-sextupole source in this instrument. Beam-based measurements of the skew sextupole component in the BGI magnet were performed, in order to benchmark the BGI magnetic model and to provide quantitative checks of sextupole corrections determined empirically to minimize the beam-losses. In this contribution, results of the successfully performed measurements are presented, including tune feed-down, chromatic coupling and resonance driving terms.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST004

About •

Received ※ 08 June 2022 — Revised ※ 18 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 23 June 2022

Cite •

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

MOPOST005

The HL-LHC Project Gets Ready for Its Deployment

50

M. Zerlauth, O.S. Brüning, B. Di Girolamo, P. Fessia, C. Gaignant, H. Garcia Gavela, E.H. Maclean, M. Modena, Th. Otto, L.J. Tavian, G. Vandoni
CERN, Meyrin, Switzerland

Following the successful completion of the second long shutdown (LS2), the Large Hadron Collider (LHC) is preparing for its final operational run before the majority of the High Luminosity Upgrade (HL-LHC) will be installed during the third Long Shutdown starting in 2026. The HL-LHC upgrade will enable a further tenfold increase in integrated luminosity delivered to the ATLAS and CMS experiments, starting by an upgrade of the machine protection, collimation and shielding systems in LS2, and followed by the deployment of novel key technologies, including Nb₃Sn based insertion region magnets, cold powering by MgB₂ superconducting links and integration of Nb crab-cavities to compensate the effects of a larger crossing angle. After a period of intensive R&D and prototyping, the project is now entering the phase of industrialization and series production for all main components. In this contribution, we provide an overview of the project status and plans for deployment and performance ramp-up. Progress on the validation of key technologies, status of prototypes and series production as well as the final integration studies for the HL equipment are summarized. These are accompanied by the imminent completion of major civil engineering work and the start of infrastructure installations. Initial operational experience will be gained at the Inner Triplet (IT) String, presently in assembly at CERN’s Superconducting Magnet Test Facility, which will enable a fully integrated test of the main magnets, powering, and protection systems in the actual HL-LHC insertion configuration.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST005

About •

Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 18 June 2022

Cite •

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

MOPOST006

Beam Commissioning and Optimisation in the CERN Proton Synchrotron After the Upgrade of the LHC Injectors

54

A. Huschauer, M.R. Coly, D.G. Cotte, H. Damerau, M. Delrieux, J.-C. Dumont, Y. Dutheil, S.E.R. Easton, M.A. Fraser, O. Hans, G.I. Imesch, S. Joly, A. Lasheen, C.L. Lombard, R. Maillet, B. Mikulec, J.-M. Nonglaton, S. Sainz Perez, B. Salvant, R. Suykerbuyk, F. Tecker, R. Valera Teruel
CERN, Meyrin, Switzerland

The CERN LHC injector chain underwent a major upgrade during the Long Shutdown 2 (LS2) in the framework of the LHC Injectors Upgrade (LIU) project. After 2 years of installation work, the Proton Synchrotron (PS) was restarted in 2021 with the goal to achieve pre-LS2 beam quality by the end of 2021. This contribution details the main beam commissioning milestones, encountered difficulties and lessons learned. The status of the fixed-target and LHC beams will be given and improvements in terms of performance, controls and tools described.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST006

About •

Received ※ 01 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 02 July 2022

Cite •

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

MOPOST008

Simulations of Protons to Extraction at Gγ=7.5 in the AGS Booster

62

K. Hock, H. Huang, F. Méot
BNL, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
To prepare for polarized helion collisions at the Electron Ion Collider (EIC), polarization transmission at the injectors for the Hadron Storage Ring must be studied and optimized. To this effect, an AC dipole has been installed in the AGS Booster to maximize polarization transmission of helions through several intrinsic resonances. This installation also allows polarized protons to be extracted at higher energy without polarization loss. By increasing the proton extraction energy from $Gγ$ = 4.5 to $Gγ$ = 7.5, protons will cross the $Gγ$ = 0 + ν_y$ and $Gγ = 12 - ν_y$ depolarizing vertical intrinsic resonances, the $Gγ$ = 5, 6, and 7 imperfection resonances in addition to the $Gγ$ = 3, 4 that are crossed in the present configuration, and be injected into the AGS at a higher rigidity. By simulation, it is determined that there is sufficient strength of the AC dipole to fully flip the spin spin through each of the intrinsic resonances, and there is sufficient corrector current to preserve polarization through the three additional imperfection resonances. The higher injection rigidity facilitates the horizontal and vertical tunes being placed inside the AGS spin-tune gap at injection due to a substantial improvement on the AGS admittance at injection.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST008

About •

Received ※ 06 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022

Cite •

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

MOPOST009

EIC Crab Cavity Multipole Analysis and Their Effects on Dynamic Aperture

66

Q. Wu, B.P. Xiao
BNL, Upton, New York, USA
S.U. De Silva
ODU, Norfolk, Virginia, USA
Z. Li
SLAC, Menlo Park, California, USA
Y. Luo
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
Crab cavity is essential for retrieving the loss in luminosity due to the large crossing angle in the two colliding beam lines of the Electron Ion Collider (EIC). Due to the asymmetric design of the proton beam crab cavity, the fundamental mode consists of contributions from higher order multipoles. These multipole modes may change during fabrication and installation of the cavities, and therefore affect the local dynamic aperture. Thresholds for each order of the multipoles are applied to ensure dynamic aperture requirements at these crab cavities. In this paper, we analyzed the strength of the multipoles due to fabrication and installation accuracies, and set limitations to each procedure to maintain the dynamic aperture requirement.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST009

About •

Received ※ 06 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 10 July 2022

Cite •

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

MOPOST037

Characterisation of Bunch-by-Bunch Tune Shift Effects in the CERN SPS

148

I. Mases Solé, H. Bartosik, V. Kain, K. Paraschou, M. Schenk, C. Zannini
CERN, Meyrin, Switzerland

After the implementation of major upgrades as part of the LHC Injector Upgrade Project (LIU), the Super Proton Synchrotron (SPS) delivers high intensity bunch trains with 25 ns bunch spacing to the Large Hadron Collider (LHC) at CERN. These beams are exposed to several collective effects in the SPS, such as beam coupling impedance, space charge and electron cloud, leading to relatively large bunch-by-bunch coherent and incoherent tune shifts. Tune correction to the nominal values at injection is crucial to ensure beam stability and good beam transmission. During the beam commissioning of the SPS, measurements of the bunch-by-bunch coherent tune shifts have been conducted under different beam conditions, together with appropriate corrections of the average tunes at each injection. In this paper, we describe the methodology that has been developed to acquire bunch-by-bunch position data and to perform online computations of the coherent tune spectra of each bunch using refined Fourier transform analysis. The experimental data are compared to multiparticle tracking simulations using the SPS impedance model, in view of developing an accurate model for tune correction in the SPS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST037

About •

Received ※ 03 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022

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

MOPOPT040

Summary of the Post-Long Shutdown 2 LHC Hardware Commissioning Campaign

335

A. Apollonio, O.Ø. Andreassen, A. Antoine, T. Argyropoulos, M.C. Bastos, M. Bednarek, B. Bordini, K. Brodzinski, A. Calia, Z. Charifoulline, G.-J. Coelingh, G. D’Angelo, D. Delikaris, R. Denz, L. Fiscarelli, V. Froidbise, M.A. Galilée, J.C. Garnier, R. Gorbonosov, P. Hagen, M. Hostettler, D. Jacquet, S. Le Naour, D. Mirarchi, V. Montabonnet, B.I. Panev, T.H.B. Persson, T. Podzorny, M. Pojer, E. Ravaioli, F. Rodriguez-Mateos, A.P. Siemko, M. Solfaroli, J. Spasic, A. Stanisz, J. Steckert, R. Steerenberg, S. Sudak, H. Thiesen, E. Todesco, G. Trad, J.A. Uythoven, S. Uznanski, A.P. Verweij, J. Wenninger, G.P. Willering, D. Wollmann, S. Yammine
CERN, Meyrin, Switzerland
V. Vizziello
INFN/LASA, Segrate (MI), Italy

In this contribution we provide a summary of the LHC hardware commissioning campaign following the second CERN Long Shutdown (LS2), initially targeting the nominal LHC energy of 7 TeV. A summary of the test procedures and tools used for testing the LHC superconducting circuits is given, together with statistics on the successful test execution. The paper then focuses on the experience and observations during the main dipole training campaign, describing the encountered problems, the related analysis and mitigation measures, ultimately leading to the decision to reduce the energy target to 6.8 TeV. The re-commissioning of two powering sectors, following the identified problems, is discussed in detail. The paper concludes with an outlook to the future hardware commissioning campaigns, discussing the lessons learnt and possible strategies moving forward.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT040

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022

Cite •

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