IPAC2018 - List of Authors (Hessler, C.)

Paper	Title	Page
MOPMF063	Asynchronous Beam Dump Tests at LHC	265
	C. Wiesner, W. Bartmann, C. Bracco, E. Carlier, L. Ducimetière, M.I. Frankl, M.A. Fraser, B. Goddard, C. Heßler, T. Kramer, A. Lechner, N. Magnin, V. Senaj, D. Wollmann CERN, Geneva, Switzerland
	The detailed understanding of the beam-loss pattern in case of an asynchronous beam dump is essential for the safe operation of the future High Luminosity LHC (HL-LHC) with nearly twice the nominal LHC beam intensity, leading to correspondingly higher energy deposition on the protection elements. An asynchronous beam dump is provoked when the rise time of the extraction kickers is not synchronized to the 3 us long particle-free abort gap. Thus, particles that are not absorbed by dedicated protection elements can be lost on the machine aperture. Since asynchronous beam dumps are among the most critical failure cases of the LHC, experimental tests at low intensity are performed routinely. This paper reviews recent asynchronous beam dump tests performed in the LHC. It describes the test conditions, discusses the beam-loss behaviour and presents simulation and measurement results. In particular, it examines a test event from May 2016, which led to the quench of four superconducting magnets in the extraction region and which was studied by a dedicated beam experiment in December 2017.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF063
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAF031	Beam Simulation Studies for the Upgrade of the SPS Beam Dumping System	747
	C. Heßler, W. Bartmann, E. Carlier, L. Ducimetière, B. Goddard, F.M. Velotti CERN, Geneva, Switzerland
	The SPS at CERN currently uses a beam dumping system that is installed in the long straight section 1 (LSS1) of the SPS. This system consists of two beam stopper blocks for low and high energy beams, as well as two vertical and three horizontal kicker magnets, which deflect and dilute the beam on the dumps. Within the frame of the LHC injector upgrade project (LIU) the beam dumping system will be relocated to long straight section 5 (LSS5) and upgraded with an additional vertical kicker, new main switches and a single new beam dump, which covers the full energy range. The impact of a possible increase of the vertical kicker rise time on the beam has been studied in simulations with MAD-X for the different optics in the SPS. Furthermore, the impact on the beam in failure scenarios such as the non-firing of one kicker has been investigated. The results of these studies will be presented and discussed in this paper. Operational mitigation methods to deal with an increased rise time will also be discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAF031
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAF032	Beam Transfer Line Design to the SPS Beam Dump Facility	751
	Y. Dutheil, J. Bauche, M. Calviani, L.A. Dougherty, M.A. Fraser, B. Goddard, C. Heßler, J. Kurdej, E. Lopez Sola CERN, Geneva, Switzerland
	Studies for the SPS Beam Dump Facility (BDF) are ongoing within the scope of the Physics Beyond Collider project. The BDF is a proposed fixed target facility to be installed in the SPS North Area, to accommodate the SHiP experiment (Search for Hidden Particles), which is most notably aiming at studying hidden sector particles. This experiment requires a high intensity slowly extracted 400 GeV proton beam with 4·10¹³ protons per 1 s spill to achieve 4·10¹⁹ protons on target per year. The extraction and transport scheme will make use of the first 600 m of the existing North Area extraction line. In this paper, we will present the design of the additional 600 m of transfer line towards BDF branching off from the existing line and discuss the detailed design of the BDF beam line, its components and optics. We present the latest results on the study and design of a new laminated Lambertson splitter magnet to provide fast switch between the current North Area experiments and the BDF. The latest specification of a dipole dilution system used to reduce the local peak power of the beam on the target is also presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAF032
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAF033	Beam Optics Studies for BDF and for Tests of a Prototype Target	754
	C. Heßler, M. Calviani, Y. Dutheil, M.A. Fraser, B. Goddard, V. Kain, E. Lopez Sola, F.M. Velotti CERN, Geneva, Switzerland
	Within the frame of the Physics Beyond Collider project a new fixed target facility at the SPS North Area, the so-called Beam Dump Facility (BDF), is under study. BDF requires a high intensity slowly extracted 400 GeV proton beam with 4·10¹³ protons per 1 s spill to achieve 4·10¹⁹ protons on target per year. This results in an exceptionally high average beam power of 355 kW on the target, which is a major challenge. To validate the target design, a test of a prototype target is planned for 2018 at an existing North Area beam line. A large part of this beam line is in common with the future BDF beam line with comparable beam characteristics and several measurement campaigns were performed in 2017 to study the optics of the line in preparation for the test. The intrinsic characteristics of the slow extraction process make the precise characterisation of the beam reaching the target particularly challenging. This paper presents beam and lattice characterisation methods and associated measurement results.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAF033
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMG002	Beam Dump Facility Target: Design Status and Beam Tests in 2018	2604
	E. Lopez Sola, O. Aberle, P. Avigni, L. Bianchi, J. Busom, M. Calviani, M. Casolino, J.P.C. Espadanal, M.A. Fraser, S. Girod, B. Goddard, D. Grenier, M. Guinchard, C. Heßler, R. Illan Fiastre, R. Jacobsson, M. Lamont, A. Ortega Rolo, B. Riffaud, G. Romagnoli, L. Zuccalli CERN, Geneva, Switzerland
	The Beam Dump Facility (BDF) Project, currently in its design phase, is a proposed general-purpose fixed target facility at CERN, dedicated to the Search for Hidden Particles (SHiP) experiment in its initial phase. At the core of the installation resides the target/dump assembly, whose aim is to fully absorb the high intensity 400 GeV/c SPS beam and produce charmed mesons. In addition to high thermo-mechanical loads, the most challenging aspects of the proposed installation lie in very high energy and power density deposition that are reached during operation. In order to validate the design of the BDF target, a scaled prototype is going to be tested during 2018 in the North Area at CERN, upstream the existing beryllium primary targets. The prototype testing under representative beam scenarios will allow having an insight of the material response in an unprecedented regime. Online monitoring and an extensive Post Irradiation Experimental (PIE) campaign are foreseen. The current contribution will detail the design and handling aspects of the innovative Target Complex as well as the design of the BDF target/dump core and the design and construction of the prototype target assembly.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPMG002
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Asynchronous Beam Dump Tests at LHC

265

C. Wiesner, W. Bartmann, C. Bracco, E. Carlier, L. Ducimetière, M.I. Frankl, M.A. Fraser, B. Goddard, C. Heßler, T. Kramer, A. Lechner, N. Magnin, V. Senaj, D. Wollmann
CERN, Geneva, Switzerland

The detailed understanding of the beam-loss pattern in case of an asynchronous beam dump is essential for the safe operation of the future High Luminosity LHC (HL-LHC) with nearly twice the nominal LHC beam intensity, leading to correspondingly higher energy deposition on the protection elements. An asynchronous beam dump is provoked when the rise time of the extraction kickers is not synchronized to the 3 us long particle-free abort gap. Thus, particles that are not absorbed by dedicated protection elements can be lost on the machine aperture. Since asynchronous beam dumps are among the most critical failure cases of the LHC, experimental tests at low intensity are performed routinely. This paper reviews recent asynchronous beam dump tests performed in the LHC. It describes the test conditions, discusses the beam-loss behaviour and presents simulation and measurement results. In particular, it examines a test event from May 2016, which led to the quench of four superconducting magnets in the extraction region and which was studied by a dedicated beam experiment in December 2017.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF063

Export •

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

TUPAF031

Beam Simulation Studies for the Upgrade of the SPS Beam Dumping System

747

C. Heßler, W. Bartmann, E. Carlier, L. Ducimetière, B. Goddard, F.M. Velotti
CERN, Geneva, Switzerland

The SPS at CERN currently uses a beam dumping system that is installed in the long straight section 1 (LSS1) of the SPS. This system consists of two beam stopper blocks for low and high energy beams, as well as two vertical and three horizontal kicker magnets, which deflect and dilute the beam on the dumps. Within the frame of the LHC injector upgrade project (LIU) the beam dumping system will be relocated to long straight section 5 (LSS5) and upgraded with an additional vertical kicker, new main switches and a single new beam dump, which covers the full energy range. The impact of a possible increase of the vertical kicker rise time on the beam has been studied in simulations with MAD-X for the different optics in the SPS. Furthermore, the impact on the beam in failure scenarios such as the non-firing of one kicker has been investigated. The results of these studies will be presented and discussed in this paper. Operational mitigation methods to deal with an increased rise time will also be discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAF031

Export •

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

TUPAF032

Beam Transfer Line Design to the SPS Beam Dump Facility

751

Y. Dutheil, J. Bauche, M. Calviani, L.A. Dougherty, M.A. Fraser, B. Goddard, C. Heßler, J. Kurdej, E. Lopez Sola
CERN, Geneva, Switzerland

Studies for the SPS Beam Dump Facility (BDF) are ongoing within the scope of the Physics Beyond Collider project. The BDF is a proposed fixed target facility to be installed in the SPS North Area, to accommodate the SHiP experiment (Search for Hidden Particles), which is most notably aiming at studying hidden sector particles. This experiment requires a high intensity slowly extracted 400 GeV proton beam with 4·10¹³ protons per 1 s spill to achieve 4·10¹⁹ protons on target per year. The extraction and transport scheme will make use of the first 600 m of the existing North Area extraction line. In this paper, we will present the design of the additional 600 m of transfer line towards BDF branching off from the existing line and discuss the detailed design of the BDF beam line, its components and optics. We present the latest results on the study and design of a new laminated Lambertson splitter magnet to provide fast switch between the current North Area experiments and the BDF. The latest specification of a dipole dilution system used to reduce the local peak power of the beam on the target is also presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAF032

Export •

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

TUPAF033

Beam Optics Studies for BDF and for Tests of a Prototype Target

754

C. Heßler, M. Calviani, Y. Dutheil, M.A. Fraser, B. Goddard, V. Kain, E. Lopez Sola, F.M. Velotti
CERN, Geneva, Switzerland

Within the frame of the Physics Beyond Collider project a new fixed target facility at the SPS North Area, the so-called Beam Dump Facility (BDF), is under study. BDF requires a high intensity slowly extracted 400 GeV proton beam with 4·10¹³ protons per 1 s spill to achieve 4·10¹⁹ protons on target per year. This results in an exceptionally high average beam power of 355 kW on the target, which is a major challenge. To validate the target design, a test of a prototype target is planned for 2018 at an existing North Area beam line. A large part of this beam line is in common with the future BDF beam line with comparable beam characteristics and several measurement campaigns were performed in 2017 to study the optics of the line in preparation for the test. The intrinsic characteristics of the slow extraction process make the precise characterisation of the beam reaching the target particularly challenging. This paper presents beam and lattice characterisation methods and associated measurement results.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAF033

Export •

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

WEPMG002

Beam Dump Facility Target: Design Status and Beam Tests in 2018

2604

E. Lopez Sola, O. Aberle, P. Avigni, L. Bianchi, J. Busom, M. Calviani, M. Casolino, J.P.C. Espadanal, M.A. Fraser, S. Girod, B. Goddard, D. Grenier, M. Guinchard, C. Heßler, R. Illan Fiastre, R. Jacobsson, M. Lamont, A. Ortega Rolo, B. Riffaud, G. Romagnoli, L. Zuccalli
CERN, Geneva, Switzerland

The Beam Dump Facility (BDF) Project, currently in its design phase, is a proposed general-purpose fixed target facility at CERN, dedicated to the Search for Hidden Particles (SHiP) experiment in its initial phase. At the core of the installation resides the target/dump assembly, whose aim is to fully absorb the high intensity 400 GeV/c SPS beam and produce charmed mesons. In addition to high thermo-mechanical loads, the most challenging aspects of the proposed installation lie in very high energy and power density deposition that are reached during operation. In order to validate the design of the BDF target, a scaled prototype is going to be tested during 2018 in the North Area at CERN, upstream the existing beryllium primary targets. The prototype testing under representative beam scenarios will allow having an insight of the material response in an unprecedented regime. Online monitoring and an extensive Post Irradiation Experimental (PIE) campaign are foreseen. The current contribution will detail the design and handling aspects of the innovative Target Complex as well as the design of the BDF target/dump core and the design and construction of the prototype target assembly.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPMG002

Export •

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