HB2023 - List of Authors (Damerau, H.)

Paper	Title	Page
MOA1I1	Beam Performance with the LHC Injectors Upgrade	1
	G. Rumolo, S.C.P. Albright, R. Alemany-Fernández, M.E. Angoletta, C. Antuono, T. Argyropoulos, F. Asvesta, M.J. Barnes, H. Bartosik, P. Baudrenghien, G. Bellodi, N. Biancacci, C. Bracco, N. Bruchon, E. Carlier, J. Coupard, H. Damerau, G.P. Di Giovanni, A. Findlay, M.A. Fraser, A. Funken, R. Garoby, S.S. Gilardoni, B. Goddard, G. Hagmann, K. Hanke, A. Huschauer, G. Iadarola, V. Kain, I. Karpov, J.-B. Lallement, A. Lasheen, T.E. Levens, K.S.B. Li, A.M. Lombardi, E.H. Maclean, D. Manglunki, I. Mases Solé, M. Meddahi, L. Mether, B. Mikulec, E. Montesinos, Y. Papaphilippou, G. Papotti, K. Paraschou, C. Pasquino, F. Pedrosa, T. Prebibaj, S. Prodon, D. Quartullo, F. Roncarolo, B. Salvant, M. Schenk, R. Scrivens, E.N. Shaposhnikova, L. Sito, P.K. Skowroński, A. Spierer, R. Steerenberg, M. Sullivan, F.M. Velotti, R. Veness, C. Vollinger, R. Wegner, C. Zannini, E. de la Fuente CERN, Meyrin, Switzerland T. Prebibaj IAP, Frankfurt am Main, Germany
	The LHC Injectors Upgrade (LIU) project was put in place between 2010 and 2021 to increase the intensity and brightness in the LHC injectors to match the challenging requirements of the High-Luminosity LHC (HL-LHC) project, while ensuring reliable operation of the injectors complex up to the end of the HL-LHC era (ca. 2040). During the 2019-2020 CERN accelerators shutdown, extensive hardware modifications were implemented in the entire LHC proton and ion injection chains, involving the new Linac4, the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS), the Super Proton Synchrotron (SPS) and the ion PS injectors, i.e. the Linac3 and the Low Energy Ion Ring (LEIR). Since 2021, beams have been recommissioned throughout the injectors’ chain and the beam parameters are being gradually ramped up to meet the LIU specifications using new beam dynamics solutions adapted to the upgraded accelerators. This paper focuses on the proton beams and describes the current state of the art.
	Slides MOA1I1 [10.002 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-MOA1I1
About •	Received ※ 29 September 2023 — Revised ※ 05 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 18 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THAFP08	Performance of the Ion Chain at the CERN Injector Complex and Transmission Studies During the 2023 Slip Stacking Commissioning	418
	M. Slupecki, S.C.P. Albright, R. Alemany-Fernández, M.E. Angoletta, T. Argyropoulos, H. Bartosik, P. Baudrenghien, G. Bellodi, M. Bozzolan, R. Bruce, C. Carli, J. Cenede, H. Damerau, A. Frassier, D. Gamba, G. Hagmann, A. Huschauer, V. Kain, G. Khatri, D. Küchler, A. Lasheen, K.S.B. Li, E. Mahner, G. Papotti, G. Piccinini, A. Rey, M. Schenk, R. Scrivens, A. Spierer, G. Tranquille, D. Valuch, F.M. Velotti, R. Wegner CERN, Meyrin, Switzerland E. Waagaard EPFL, Lausanne, Switzerland
	The 2023 run has been decisive for the LHC Ion Injector Complex. It demonstrated the capability of producing full trains of momentum slip stacked lead ions in the SPS. Slip stacking is a technique of interleaving particle trains, reducing the bunch spacing in SPS from 100 ns to 50 ns. It is needed to reach the total ion intensity requested by the HL-LHC project, as defined by updated common LIU/HL-LHC target beam parameters. This paper reviews the lead beam characteristics across the Ion Injector Complex, including transmission efficiencies up to the SPS extraction. It also documents the difficulties found during the commissioning and the solutions put in place.
	Slides THAFP08 [1.114 MB]
	Poster THAFP08 [1.995 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THAFP08
About •	Received ※ 01 October 2023 — Revised ※ 07 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 21 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THBP17	Transverse Coherent Instability Studies for the High-Energy Part of the Muon Collider Complex	491
	D. Amorim, F. Batsch, L. Bottura, D. Calzolari, C. Carli, H. Damerau, A. Grudiev, A. Lechner, E. Métral, D. Schulte, K. Skoufaris CERN, Meyrin, Switzerland A. Chancé CEA-DRF-IRFU, France T. Pieloni EPFL, Lausanne, Switzerland
	Funding: This project has received funding from the European Union¿s Research and Innovation programme under GA No 101094300 and the Swiss Accelerator Research and Technology (CHART) program (www.chart.ch). The International Muon Collider Collaboration (IMCC) is studying a 3 TeV center-of-mass muon collider ring, as well as a possible next stage at 10 TeV. Muons being 200 times heavier than electrons, limitations from synchrotron radiation are mostly suppressed, but the muon decay drives the accelerator chain design. After the muon and anti-muon bunches are produced and 6D cooled, a series of Linac, recirculating Linac and Rapid Cycling Synchrotron (RCS) quickly accelerate the bunches before the collider ring. A large number of RF cavities are required in the RCS to ensure that over 90% of the muons survive in each ring. The effects of cavities higher-order modes on transverse coherent stability have been looked at in detail, including the one of a bunch offset in the cavities, along with possible mitigation measures. In the collider ring, the decay of high-energy muons is a challenge for heat load management and radiation shielding. A tungsten liner would protect the superconducting magnet from decay products. Impedance and related beam stability have been investigated to identify the minimum vacuum chamber radius and transverse damper properties required for stable beams.
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP17
About •	Received ※ 29 September 2023 — Revised ※ 06 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 01 November 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THBP42	Longitudinal Loss of Landau Damping in Double Harmonic RF Systems below Transition Energy	575
	L. Intelisano, H. Damerau, I. Karpov CERN, Meyrin, Switzerland
	Landau damping plays a crucial role in ensuring single-bunch stability in hadron synchrotrons. In the longitudinal plane, loss of Landau damping (LLD) occurs when a coherent mode of oscillation moves out of the incoherent synchrotron frequency band. The LLD threshold is studied for a purely inductive impedance below transition energy, specifically considering the common case of double harmonic RF systems operating in counter-phase at the bunch position. The additional focusing force due to beam-induced voltage distorts the potential well, ultimately collapsing the bucket. The limiting conditions for a binomial particle distribution are calculated. Furthermore, the contribution focuses on the configuration of the higher-harmonic RF system at four times the fundamental RF frequency operating in phase. In this case, the LLD threshold shows a non-monotonic behavior with a zero threshold where the derivative of the synchrotron frequency distribution is positive. The findings are obtained employing semi-analytical calculations using the MELODY code.
	Poster THBP42 [1.710 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP42
About •	Received ※ 30 September 2023 — Revised ※ 08 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 14 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THBP43	Intensity Effects in a Chain of Muon RCSs	579
	F. Batsch, D. Amorim, H. Damerau, A. Grudiev, I. Karpov, E. Métral, D. Schulte CERN, Meyrin, Switzerland A. Chancé CEA, Gif-sur-Yvette, France S. Udongwo Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
	Funding: Funded by the European Union under Grant Agreement n.101094300 The muon collider offers an attractive path to a compact, multi-TeV lepton collider. However, the short muon lifetime leads to stringent requirements on the fast energy increase. While extreme energy gains in the order of several GeV per turn are crucial for a high elevated muon survival rate, ultra-short and intense bunches are needed to achieve large luminosity. The longitudinal beam dynamics of a chain of rapid cycling synchrotrons (RCS) for acceleration from around 60 GeV to several TeV is being investigated in the framework of the International Muon Collider Collaboration. Each RCS must have a distributed radio-frequency (RF) system with several hundred RF stations to establish stable synchrotron motion. In this contribution, the beam-induced voltage in each RCS is studied, assuming a single high-intensity bunch per beam in each direction and ILC-like 1.3 GHz accelerating structures. The impact of single- and multi-turn wakefields on longitudinal stability and RF power requirements is analysed with particle tracking simulations. Special attention is moreover paid to the beam power deposited into the higher-order modes of the RF cavities.
	Poster THBP43 [1.345 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP43
About •	Received ※ 29 September 2023 — Revised ※ 05 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 10 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THBP45	Longitudinal Collective Effects at Beam Transfer from PS to SPS at CERN	587
	A. Lasheen, H. Damerau, I. Karpov, G. Papotti, E.T. Vinten CERN, Meyrin, Switzerland
	The hardware upgrades of the LHC Injectors Upgrade (LIU) project at CERN were completed during the Long Shutdown 2 (2019-2021) to prepare the injectors for the beams required by the High Luminosity (HL) LHC. Doubling the bunch intensity leads to new challenges due to collective effects. Although many bottlenecks were already solved, a remaining limitation is the important loss of particles at transfer from the Proton Synchrotron (PS) to the Super Proton Synchrotron (SPS). The maximum transmission achieved since the restart in 2021 is in the order of 90%, yet leading to unnecessary activation of the SPS. The losses are distributed at various instants of the SPS cycle: fast intensity decay right after injection, slow losses along the injection plateau while waiting for multiple injections from the PS, and uncaptured beam removed at start of acceleration. In this contribution, the focus is on longitudinal aspects of transfer losses and more specifically on intensity effects during the non-adiabatic bunch shorting performed in the PS prior to extraction, as well as on the longitudinal mismatch at injection due to misaligned bunch phases in the SPS caused by transient beam loading.
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP45
About •	Received ※ 01 October 2023 — Revised ※ 08 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 15 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Beam Performance with the LHC Injectors Upgrade

1

G. Rumolo, S.C.P. Albright, R. Alemany-Fernández, M.E. Angoletta, C. Antuono, T. Argyropoulos, F. Asvesta, M.J. Barnes, H. Bartosik, P. Baudrenghien, G. Bellodi, N. Biancacci, C. Bracco, N. Bruchon, E. Carlier, J. Coupard, H. Damerau, G.P. Di Giovanni, A. Findlay, M.A. Fraser, A. Funken, R. Garoby, S.S. Gilardoni, B. Goddard, G. Hagmann, K. Hanke, A. Huschauer, G. Iadarola, V. Kain, I. Karpov, J.-B. Lallement, A. Lasheen, T.E. Levens, K.S.B. Li, A.M. Lombardi, E.H. Maclean, D. Manglunki, I. Mases Solé, M. Meddahi, L. Mether, B. Mikulec, E. Montesinos, Y. Papaphilippou, G. Papotti, K. Paraschou, C. Pasquino, F. Pedrosa, T. Prebibaj, S. Prodon, D. Quartullo, F. Roncarolo, B. Salvant, M. Schenk, R. Scrivens, E.N. Shaposhnikova, L. Sito, P.K. Skowroński, A. Spierer, R. Steerenberg, M. Sullivan, F.M. Velotti, R. Veness, C. Vollinger, R. Wegner, C. Zannini, E. de la Fuente
CERN, Meyrin, Switzerland
T. Prebibaj
IAP, Frankfurt am Main, Germany

The LHC Injectors Upgrade (LIU) project was put in place between 2010 and 2021 to increase the intensity and brightness in the LHC injectors to match the challenging requirements of the High-Luminosity LHC (HL-LHC) project, while ensuring reliable operation of the injectors complex up to the end of the HL-LHC era (ca. 2040). During the 2019-2020 CERN accelerators shutdown, extensive hardware modifications were implemented in the entire LHC proton and ion injection chains, involving the new Linac4, the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS), the Super Proton Synchrotron (SPS) and the ion PS injectors, i.e. the Linac3 and the Low Energy Ion Ring (LEIR). Since 2021, beams have been recommissioned throughout the injectors’ chain and the beam parameters are being gradually ramped up to meet the LIU specifications using new beam dynamics solutions adapted to the upgraded accelerators. This paper focuses on the proton beams and describes the current state of the art.

Slides MOA1I1 [10.002 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-MOA1I1

About •

Received ※ 29 September 2023 — Revised ※ 05 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 18 October 2023

Cite •

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

THAFP08

Performance of the Ion Chain at the CERN Injector Complex and Transmission Studies During the 2023 Slip Stacking Commissioning

418

M. Slupecki, S.C.P. Albright, R. Alemany-Fernández, M.E. Angoletta, T. Argyropoulos, H. Bartosik, P. Baudrenghien, G. Bellodi, M. Bozzolan, R. Bruce, C. Carli, J. Cenede, H. Damerau, A. Frassier, D. Gamba, G. Hagmann, A. Huschauer, V. Kain, G. Khatri, D. Küchler, A. Lasheen, K.S.B. Li, E. Mahner, G. Papotti, G. Piccinini, A. Rey, M. Schenk, R. Scrivens, A. Spierer, G. Tranquille, D. Valuch, F.M. Velotti, R. Wegner
CERN, Meyrin, Switzerland
E. Waagaard
EPFL, Lausanne, Switzerland

The 2023 run has been decisive for the LHC Ion Injector Complex. It demonstrated the capability of producing full trains of momentum slip stacked lead ions in the SPS. Slip stacking is a technique of interleaving particle trains, reducing the bunch spacing in SPS from 100 ns to 50 ns. It is needed to reach the total ion intensity requested by the HL-LHC project, as defined by updated common LIU/HL-LHC target beam parameters. This paper reviews the lead beam characteristics across the Ion Injector Complex, including transmission efficiencies up to the SPS extraction. It also documents the difficulties found during the commissioning and the solutions put in place.

Slides THAFP08 [1.114 MB]

Poster THAFP08 [1.995 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THAFP08

About •

Received ※ 01 October 2023 — Revised ※ 07 October 2023 — Accepted ※ 11 October 2023 — Issued ※ 21 October 2023

Cite •

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

THBP17

Transverse Coherent Instability Studies for the High-Energy Part of the Muon Collider Complex

491

D. Amorim, F. Batsch, L. Bottura, D. Calzolari, C. Carli, H. Damerau, A. Grudiev, A. Lechner, E. Métral, D. Schulte, K. Skoufaris
CERN, Meyrin, Switzerland
A. Chancé
CEA-DRF-IRFU, France
T. Pieloni
EPFL, Lausanne, Switzerland

Funding: This project has received funding from the European Union¿s Research and Innovation programme under GA No 101094300 and the Swiss Accelerator Research and Technology (CHART) program (www.chart.ch).
The International Muon Collider Collaboration (IMCC) is studying a 3 TeV center-of-mass muon collider ring, as well as a possible next stage at 10 TeV. Muons being 200 times heavier than electrons, limitations from synchrotron radiation are mostly suppressed, but the muon decay drives the accelerator chain design. After the muon and anti-muon bunches are produced and 6D cooled, a series of Linac, recirculating Linac and Rapid Cycling Synchrotron (RCS) quickly accelerate the bunches before the collider ring. A large number of RF cavities are required in the RCS to ensure that over 90% of the muons survive in each ring. The effects of cavities higher-order modes on transverse coherent stability have been looked at in detail, including the one of a bunch offset in the cavities, along with possible mitigation measures. In the collider ring, the decay of high-energy muons is a challenge for heat load management and radiation shielding. A tungsten liner would protect the superconducting magnet from decay products. Impedance and related beam stability have been investigated to identify the minimum vacuum chamber radius and transverse damper properties required for stable beams.

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP17

About •

Received ※ 29 September 2023 — Revised ※ 06 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 01 November 2023

Cite •

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

THBP42

Longitudinal Loss of Landau Damping in Double Harmonic RF Systems below Transition Energy

575

L. Intelisano, H. Damerau, I. Karpov
CERN, Meyrin, Switzerland

Landau damping plays a crucial role in ensuring single-bunch stability in hadron synchrotrons. In the longitudinal plane, loss of Landau damping (LLD) occurs when a coherent mode of oscillation moves out of the incoherent synchrotron frequency band. The LLD threshold is studied for a purely inductive impedance below transition energy, specifically considering the common case of double harmonic RF systems operating in counter-phase at the bunch position. The additional focusing force due to beam-induced voltage distorts the potential well, ultimately collapsing the bucket. The limiting conditions for a binomial particle distribution are calculated. Furthermore, the contribution focuses on the configuration of the higher-harmonic RF system at four times the fundamental RF frequency operating in phase. In this case, the LLD threshold shows a non-monotonic behavior with a zero threshold where the derivative of the synchrotron frequency distribution is positive. The findings are obtained employing semi-analytical calculations using the MELODY code.

Poster THBP42 [1.710 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP42

About •

Received ※ 30 September 2023 — Revised ※ 08 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 14 October 2023

Cite •

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

THBP43

Intensity Effects in a Chain of Muon RCSs

579

F. Batsch, D. Amorim, H. Damerau, A. Grudiev, I. Karpov, E. Métral, D. Schulte
CERN, Meyrin, Switzerland
A. Chancé
CEA, Gif-sur-Yvette, France
S. Udongwo
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany

Funding: Funded by the European Union under Grant Agreement n.101094300
The muon collider offers an attractive path to a compact, multi-TeV lepton collider. However, the short muon lifetime leads to stringent requirements on the fast energy increase. While extreme energy gains in the order of several GeV per turn are crucial for a high elevated muon survival rate, ultra-short and intense bunches are needed to achieve large luminosity. The longitudinal beam dynamics of a chain of rapid cycling synchrotrons (RCS) for acceleration from around 60 GeV to several TeV is being investigated in the framework of the International Muon Collider Collaboration. Each RCS must have a distributed radio-frequency (RF) system with several hundred RF stations to establish stable synchrotron motion. In this contribution, the beam-induced voltage in each RCS is studied, assuming a single high-intensity bunch per beam in each direction and ILC-like 1.3 GHz accelerating structures. The impact of single- and multi-turn wakefields on longitudinal stability and RF power requirements is analysed with particle tracking simulations. Special attention is moreover paid to the beam power deposited into the higher-order modes of the RF cavities.

Poster THBP43 [1.345 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP43

About •

Received ※ 29 September 2023 — Revised ※ 05 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 10 October 2023

Cite •

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

THBP45

Longitudinal Collective Effects at Beam Transfer from PS to SPS at CERN

587

A. Lasheen, H. Damerau, I. Karpov, G. Papotti, E.T. Vinten
CERN, Meyrin, Switzerland

The hardware upgrades of the LHC Injectors Upgrade (LIU) project at CERN were completed during the Long Shutdown 2 (2019-2021) to prepare the injectors for the beams required by the High Luminosity (HL) LHC. Doubling the bunch intensity leads to new challenges due to collective effects. Although many bottlenecks were already solved, a remaining limitation is the important loss of particles at transfer from the Proton Synchrotron (PS) to the Super Proton Synchrotron (SPS). The maximum transmission achieved since the restart in 2021 is in the order of 90%, yet leading to unnecessary activation of the SPS. The losses are distributed at various instants of the SPS cycle: fast intensity decay right after injection, slow losses along the injection plateau while waiting for multiple injections from the PS, and uncaptured beam removed at start of acceleration. In this contribution, the focus is on longitudinal aspects of transfer losses and more specifically on intensity effects during the non-adiabatic bunch shorting performed in the PS prior to extraction, as well as on the longitudinal mismatch at injection due to misaligned bunch phases in the SPS caused by transient beam loading.

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THBP45

About •

Received ※ 01 October 2023 — Revised ※ 08 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 15 October 2023

Cite •

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