IPAC2021 - List of Authors (Spiller, P.J.)

Paper	Title	Page
MOPAB175	Advanced Concepts and Technologies for Heavy Ion Synchrotrons	594
	P.J. Spiller, O. Boine-Frankenheim, L.H.J. Bozyk, S. Klammes, H. Kollmus, D. Ondreka, I. Pongrac, N. Pyka, C. Roux, K. Sugita, St. Wilfert, T. Winkler, D.F.A. Winters GSI, Darmstadt, Germany
	New concepts and technologies are developed to advance the performance of heavy ion synchrotrons. Besides fast ramping of superconducting magnets, extreme UHV technologies to stabilize dynamic vacuum and charge related loss, broad band MA cavities, space charge compensation by means of electron lenses and new cooling technologies, e.g. laser cooling, show great promise to advance the forefront of beam parameters. Several of these technologies and concepts are developed and tested at GSI/FAIR. Progress and plans will be reported.
	Poster MOPAB175 [1.367 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB175
About •	paper received ※ 11 May 2021 paper accepted ※ 21 May 2021 issue date ※ 20 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAB200	Status of the Electron Lens for Space Charge Compensation in SIS18	1880
	K. Schulte-Urlichs, S. Artikova, D. Ondreka, P.J. Spiller GSI, Darmstadt, Germany P. Apse-Apsitis, I. Steiks Riga Technical University, Riga, Latvia M. Droba, O. Meusel, H. Podlech, K.I. Thoma IAP, Frankfurt am Main, Germany
	At GSI a project has been initiated to investigate the option of space charge compensation (SCC) by use of an electron lens in order to overcome space charge (SC) limits in the synchrotrons SIS18 and SIS100 for the Facility for Antiproton and Ion Research (FAIR). The repeated crossing of resonance lines due to the synchrotron motion in bunched beams is considered one of the main drivers of SC induced beam loss in the synchrotrons. Electron lenses provide a compensation of ion beam SC by virtue of their negative charge interacting with the ions in the overlap region while a time-varying compensation can be achieved by the modulation of the electron beam. In order to demonstrate space charge compensation of bunched ion beams, an electron lens is under development for the application in SIS18. In this contribution, the status of the electron lens design will be reported putting special emphasis on its main components: the RF modulated electron gun, that is being developed within an ARIES collaboration, and the magnet system.
	Poster TUPAB200 [1.869 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB200
About •	paper received ※ 19 May 2021 paper accepted ※ 23 June 2021 issue date ※ 17 August 2021
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TUPAB372	Status of the Quadrupole Doublet Module Series Manfacturing	2388
	T. Winkler, A. Bleile, L.H.J. Bozyk, V.I. Datskov, J. Ketter, P. Kowina, J.P. Meier, N. Pyka, C. Roux, P.J. Spiller, K. Sugita, A. Waldt, St. Wilfert GSI, Darmstadt, Germany
	The 83 Quadrupole Doublet Modules (QDM) for the heavy-ion-synchrotron SIS100 of the FAIR project at GSI are highly integrated cryogenic modules containing multiple magnets. Each of eleven different QDM types consists of two units, where one unit consists of one quadrupole magnet as well as corrector magnets depending on the modules position in the accelerator Ion-Optical Lattice. Additionally, the QDMs contain cryogenic collimators, beam diagnostics, as well as cryogenic UHV beam pipes. The modules contain parts from multiple suppliers increasing the logistics behinds the QDMs design further. We present the process of the module integration, give details on the current integration status and present an outlook on the timeline for the QDM integration planning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB372
About •	paper received ※ 18 May 2021 paper accepted ※ 02 June 2021 issue date ※ 21 August 2021
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TUPAB378	Superconducting Dipole Magnets for the SIS100 Synchrotron	2401
	F. Kaether, P. Aguar Bartolome, A. Bleile, G. Golluccio, J. Ketter, P. Kosek, F. Kurian, V. Marusov, J.P. Meier, S.S. Mohite, C. Roux, P.J. Spiller, K. Sugita, A. Szwangruber, P.B. Szwangruber, A. Warth, H.G. Weiss GSI, Darmstadt, Germany
	The Facility for Antiproton and Ion Research (FAIR) is currently under construction at GSI Darmstadt, Germany. For its main accelarator, the SIS100 synchrotron, 110 superconducting dipole magnets has been produced and extensively tested. The fast-ramped Nuclotron-type superferric dipoles were manufactured with high effort regarding a precise magnetic field which could be proven by magnetic field measurements with high accuracy. Stable operation conditions at 4.5 K were achieved including an excellent quench behaviour and precise geometrical and electrical properties. An overview on design, production, operation, tests and measurement results will be given.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB378
About •	paper received ※ 19 May 2021 paper accepted ※ 21 June 2021 issue date ※ 10 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAB380	Testing of the First of Series Quadrupole Doublet Module for the SIS100 Synchrotron	2409
	P. Aguar Bartolome, M. Al Ghanem, M. Becker, A. Bleile, R. Bluemel, L.H.J. Bozyk, V.I. Datskov, W. Freisleben, A. Kario, P. Kowina, K.K. Kozlowski, F. Kurian, S. Lindner, J.P. Meier, T. Miertsch, S.S. Mohite, V.P. Plyusnin, I. Pongrac, C. Roux, C. Schroeder, P.J. Spiller, K. Sugita, A. Szwangruber, P.B. Szwangruber, F. Walter, H. Welker, St. Wilfert, T. Winkler, S. Zeller GSI, Darmstadt, Germany
	A new international facility for antiproton and ion research (FAIR) is currently under construction in Darmstadt, Germany. The high intensity primary beam required for different research experiments will be provided by the SIS100 heavy ion synchrotron. The synchrotron is composed of fast cycling superconducting magnets from which about 300 will be integrated in Quadrupole Doublet Modules (QDM). Each module consists of two units composed of a quadrupole and corrector magnets. The First of Series Quadrupole Doublet Module was delivered to the test facility at GSI in November 2019. The assembled doublet was subjected to a dedicated test program to verify the functionality of the module components at cryogenic temperature and operating conditions. The results obtained during the testing campaign will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB380
About •	paper received ※ 19 May 2021 paper accepted ※ 18 June 2021 issue date ※ 02 September 2021
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TUPAB391	Cryopanels in the Room Temperature Heavy Ion Synchrotron SIS18	2435
	S. Aumüller, L.H.J. Bozyk, P.J. Spiller GSI, Darmstadt, Germany K. Blaum MPI-K, Heidelberg, Germany
	The FAIR complex at the GSI Helmholtzzentrum will generate heavy ion beams of ultimate intensities. To achieve this goal, medium charge states have to be used. However, the probability for charge exchange in collisions with residual gas particles of such ions is much higher than for higher charge states. In order to lower the residual gas density to extreme high vacuum conditions, 65% of the circumference of SIS18 are already coated with NEG, which provides high and distributed pumping speed. Nevertheless, nobel and nobel-like components, which have very high ionization cross sections, do not get pumped by this coating. A cryogenic environment at moderate temperatures, i.e. at 50-80K, provides high pumping speed for all heavy residual gas particles. The only typical residual gas species, that cannot be pumped at this temperature is hydrogen. With an additional NEG coating the pumping will be optimized for all residual gas particles. The installation of cryogenic surfaces in the existing room temperature synchrotron SIS18 at GSI has been investigated. A prototype quadrupole chamber with cryogenic surfaces, first measurements, and simulations of the adapted accelerator are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB391
About •	paper received ※ 19 May 2021 paper accepted ※ 31 August 2021 issue date ※ 25 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPAB355	Series Production of the SIS100 Cryocatchers	3529
	L.H.J. Bozyk, S. Ahmed, P.J. Spiller GSI, Darmstadt, Germany
	The superconducting heavy ion synchrotron SIS100, which is the main accelerator of the FAIR-facility will be equipped with cryocatcher to suppress dynamic vacuum effects and to assure a reliable operation of high intensity heavy-ion beams. Subsequent to the successful validation of the prototype in 2011 as well as a First-of-Series cryocatcher, the series production of 60 cryocatcher modules meanwhile has been completed. It was released in 2018 after further design optimizations. Key findings from the series production and acceptance tests are presented as well. The First-of-Series cryocatcher has been integrated into the First-of-Series quadrupole module and has undergone several tests. These results are also illustrated in this report.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB355
About •	paper received ※ 19 May 2021 paper accepted ※ 06 July 2021 issue date ※ 16 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPAB384	Design and Beam Dynamics of the Electron Lens for Space Charge Compensation in SIS18	3614
	S. Artikova, D. Ondreka, K. Schulte-Urlichs, P.J. Spiller GSI, Darmstadt, Germany
	An electron lens for space charge compensation is being developed at GSI to increase the ion beam intensities in SIS18 for the FAIR project. It uses an electron beam of 10A maximum current at 30keV. The maximum magnetic field on-axis is 0.6T, considerably higher than the field of the existing electron cooler. The magnetic system of the lens consists of solenoids and toroids. The toroids’ vertical field component creates a significant horizontal orbit deflection in the circulating low rigidity ion beam. To correct this deflection, four correction dipoles have been introduced. As common for electron lenses, the high-power electron beam is not dumped at ground potential, but rather in a collector with a small bias potential with respect to the cathode. The present design foresees a collector at -27kV, leading to a power dissipation of 30kW, distributed over a large surface area by placing the collector in an appropriately shaped magnetic field of a pre-collector solenoid. This contribution reports on the design of the lens and presents the results of beam transport simulations for the electron beam (with space charge) and a representative ion beam, performed using the 3D CST STUDIO.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB384
About •	paper received ※ 20 May 2021 paper accepted ※ 05 July 2021 issue date ※ 31 August 2021
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THPAB157	Studying X-Ray Spectra of the SIS18 Electrostatic Septa to Measure Their Electric Field	4065
	B. Gålander, E. Kozlova, D. Ondreka, A. Sokolov, P.J. Spiller, J. Stadlmann GSI, Darmstadt, Germany
	The synchrotron SIS18 at GSI uses resonant extraction for slow beam extraction on the order of seconds. For some time, there has been an unexplained discrepancy of the slow extraction with a lower extraction efficiency than expected at the highest beam energies. Recent machine studies have indicated that the deflection by the electrostatic septum might be less than the nominal 2.5 mrad, leading to increased losses at the magnetic septum. In this paper, we pursue an idea to directly measure the voltage of the electrode gap by utilizing the fact that dark current electrons accelerated in the gap of the electrostatic extraction septum generate Bremsstrahlung X-rays when hitting the anode. The high-energy cut-off of the X-ray spectra then corresponds to the voltage of the electrode gap. Measurements of the X-ray spectra at the extraction septum of SIS18 have been performed using a solid-state CdTe detector. This technique provides an in-situ measurement of the voltage applied to the electrostatic extraction channel and has proven to be a useful diagnostics tool.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB157
About •	paper received ※ 19 May 2021 paper accepted ※ 02 September 2021 issue date ※ 19 August 2021
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THPAB356	Progress and Status on Civil Construction of the SIS100 Accelerator Building	4493
	M. Draisbach, N. Pyka, P.J. Spiller GSI, Darmstadt, Germany J. Blaurock, M. Ossendorf FAIR, Darmstadt, Germany
	Besides the accelerator machine itself, civil construction of the accelerator ring tunnel building in the northern area of the FAIR campus is a core activity of the rapidly progressing FAIR project. It will facilitate and supply the future SIS100 accelerator at 17m underground level and has been growing continuously and according to schedule since groundbreaking in 2017. This contribution presents the current status of the civil construction progress and gives an optimistic forecast for the preparation of machine installation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB356
About •	paper received ※ 20 May 2021 paper accepted ※ 06 July 2021 issue date ※ 15 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Advanced Concepts and Technologies for Heavy Ion Synchrotrons

594

P.J. Spiller, O. Boine-Frankenheim, L.H.J. Bozyk, S. Klammes, H. Kollmus, D. Ondreka, I. Pongrac, N. Pyka, C. Roux, K. Sugita, St. Wilfert, T. Winkler, D.F.A. Winters
GSI, Darmstadt, Germany

New concepts and technologies are developed to advance the performance of heavy ion synchrotrons. Besides fast ramping of superconducting magnets, extreme UHV technologies to stabilize dynamic vacuum and charge related loss, broad band MA cavities, space charge compensation by means of electron lenses and new cooling technologies, e.g. laser cooling, show great promise to advance the forefront of beam parameters. Several of these technologies and concepts are developed and tested at GSI/FAIR. Progress and plans will be reported.

Poster MOPAB175 [1.367 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB175

About •

paper received ※ 11 May 2021 paper accepted ※ 21 May 2021 issue date ※ 20 August 2021

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

TUPAB200

Status of the Electron Lens for Space Charge Compensation in SIS18

1880

K. Schulte-Urlichs, S. Artikova, D. Ondreka, P.J. Spiller
GSI, Darmstadt, Germany
P. Apse-Apsitis, I. Steiks
Riga Technical University, Riga, Latvia
M. Droba, O. Meusel, H. Podlech, K.I. Thoma
IAP, Frankfurt am Main, Germany

At GSI a project has been initiated to investigate the option of space charge compensation (SCC) by use of an electron lens in order to overcome space charge (SC) limits in the synchrotrons SIS18 and SIS100 for the Facility for Antiproton and Ion Research (FAIR). The repeated crossing of resonance lines due to the synchrotron motion in bunched beams is considered one of the main drivers of SC induced beam loss in the synchrotrons. Electron lenses provide a compensation of ion beam SC by virtue of their negative charge interacting with the ions in the overlap region while a time-varying compensation can be achieved by the modulation of the electron beam. In order to demonstrate space charge compensation of bunched ion beams, an electron lens is under development for the application in SIS18. In this contribution, the status of the electron lens design will be reported putting special emphasis on its main components: the RF modulated electron gun, that is being developed within an ARIES collaboration, and the magnet system.

Poster TUPAB200 [1.869 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB200

About •

paper received ※ 19 May 2021 paper accepted ※ 23 June 2021 issue date ※ 17 August 2021

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TUPAB372

Status of the Quadrupole Doublet Module Series Manfacturing

2388

T. Winkler, A. Bleile, L.H.J. Bozyk, V.I. Datskov, J. Ketter, P. Kowina, J.P. Meier, N. Pyka, C. Roux, P.J. Spiller, K. Sugita, A. Waldt, St. Wilfert
GSI, Darmstadt, Germany

The 83 Quadrupole Doublet Modules (QDM) for the heavy-ion-synchrotron SIS100 of the FAIR project at GSI are highly integrated cryogenic modules containing multiple magnets. Each of eleven different QDM types consists of two units, where one unit consists of one quadrupole magnet as well as corrector magnets depending on the modules position in the accelerator Ion-Optical Lattice. Additionally, the QDMs contain cryogenic collimators, beam diagnostics, as well as cryogenic UHV beam pipes. The modules contain parts from multiple suppliers increasing the logistics behinds the QDMs design further. We present the process of the module integration, give details on the current integration status and present an outlook on the timeline for the QDM integration planning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB372

About •

paper received ※ 18 May 2021 paper accepted ※ 02 June 2021 issue date ※ 21 August 2021

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TUPAB378

Superconducting Dipole Magnets for the SIS100 Synchrotron

2401

F. Kaether, P. Aguar Bartolome, A. Bleile, G. Golluccio, J. Ketter, P. Kosek, F. Kurian, V. Marusov, J.P. Meier, S.S. Mohite, C. Roux, P.J. Spiller, K. Sugita, A. Szwangruber, P.B. Szwangruber, A. Warth, H.G. Weiss
GSI, Darmstadt, Germany

The Facility for Antiproton and Ion Research (FAIR) is currently under construction at GSI Darmstadt, Germany. For its main accelarator, the SIS100 synchrotron, 110 superconducting dipole magnets has been produced and extensively tested. The fast-ramped Nuclotron-type superferric dipoles were manufactured with high effort regarding a precise magnetic field which could be proven by magnetic field measurements with high accuracy. Stable operation conditions at 4.5 K were achieved including an excellent quench behaviour and precise geometrical and electrical properties. An overview on design, production, operation, tests and measurement results will be given.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB378

About •

paper received ※ 19 May 2021 paper accepted ※ 21 June 2021 issue date ※ 10 August 2021

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TUPAB380

Testing of the First of Series Quadrupole Doublet Module for the SIS100 Synchrotron

2409

P. Aguar Bartolome, M. Al Ghanem, M. Becker, A. Bleile, R. Bluemel, L.H.J. Bozyk, V.I. Datskov, W. Freisleben, A. Kario, P. Kowina, K.K. Kozlowski, F. Kurian, S. Lindner, J.P. Meier, T. Miertsch, S.S. Mohite, V.P. Plyusnin, I. Pongrac, C. Roux, C. Schroeder, P.J. Spiller, K. Sugita, A. Szwangruber, P.B. Szwangruber, F. Walter, H. Welker, St. Wilfert, T. Winkler, S. Zeller
GSI, Darmstadt, Germany

A new international facility for antiproton and ion research (FAIR) is currently under construction in Darmstadt, Germany. The high intensity primary beam required for different research experiments will be provided by the SIS100 heavy ion synchrotron. The synchrotron is composed of fast cycling superconducting magnets from which about 300 will be integrated in Quadrupole Doublet Modules (QDM). Each module consists of two units composed of a quadrupole and corrector magnets. The First of Series Quadrupole Doublet Module was delivered to the test facility at GSI in November 2019. The assembled doublet was subjected to a dedicated test program to verify the functionality of the module components at cryogenic temperature and operating conditions. The results obtained during the testing campaign will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB380

About •

paper received ※ 19 May 2021 paper accepted ※ 18 June 2021 issue date ※ 02 September 2021

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TUPAB391

Cryopanels in the Room Temperature Heavy Ion Synchrotron SIS18

2435

S. Aumüller, L.H.J. Bozyk, P.J. Spiller
GSI, Darmstadt, Germany
K. Blaum
MPI-K, Heidelberg, Germany

The FAIR complex at the GSI Helmholtzzentrum will generate heavy ion beams of ultimate intensities. To achieve this goal, medium charge states have to be used. However, the probability for charge exchange in collisions with residual gas particles of such ions is much higher than for higher charge states. In order to lower the residual gas density to extreme high vacuum conditions, 65% of the circumference of SIS18 are already coated with NEG, which provides high and distributed pumping speed. Nevertheless, nobel and nobel-like components, which have very high ionization cross sections, do not get pumped by this coating. A cryogenic environment at moderate temperatures, i.e. at 50-80K, provides high pumping speed for all heavy residual gas particles. The only typical residual gas species, that cannot be pumped at this temperature is hydrogen. With an additional NEG coating the pumping will be optimized for all residual gas particles. The installation of cryogenic surfaces in the existing room temperature synchrotron SIS18 at GSI has been investigated. A prototype quadrupole chamber with cryogenic surfaces, first measurements, and simulations of the adapted accelerator are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB391

About •

paper received ※ 19 May 2021 paper accepted ※ 31 August 2021 issue date ※ 25 August 2021

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WEPAB355

Series Production of the SIS100 Cryocatchers

3529

L.H.J. Bozyk, S. Ahmed, P.J. Spiller
GSI, Darmstadt, Germany

The superconducting heavy ion synchrotron SIS100, which is the main accelerator of the FAIR-facility will be equipped with cryocatcher to suppress dynamic vacuum effects and to assure a reliable operation of high intensity heavy-ion beams. Subsequent to the successful validation of the prototype in 2011 as well as a First-of-Series cryocatcher, the series production of 60 cryocatcher modules meanwhile has been completed. It was released in 2018 after further design optimizations. Key findings from the series production and acceptance tests are presented as well. The First-of-Series cryocatcher has been integrated into the First-of-Series quadrupole module and has undergone several tests. These results are also illustrated in this report.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB355

About •

paper received ※ 19 May 2021 paper accepted ※ 06 July 2021 issue date ※ 16 August 2021

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WEPAB384

Design and Beam Dynamics of the Electron Lens for Space Charge Compensation in SIS18

3614

S. Artikova, D. Ondreka, K. Schulte-Urlichs, P.J. Spiller
GSI, Darmstadt, Germany

An electron lens for space charge compensation is being developed at GSI to increase the ion beam intensities in SIS18 for the FAIR project. It uses an electron beam of 10A maximum current at 30keV. The maximum magnetic field on-axis is 0.6T, considerably higher than the field of the existing electron cooler. The magnetic system of the lens consists of solenoids and toroids. The toroids’ vertical field component creates a significant horizontal orbit deflection in the circulating low rigidity ion beam. To correct this deflection, four correction dipoles have been introduced. As common for electron lenses, the high-power electron beam is not dumped at ground potential, but rather in a collector with a small bias potential with respect to the cathode. The present design foresees a collector at -27kV, leading to a power dissipation of 30kW, distributed over a large surface area by placing the collector in an appropriately shaped magnetic field of a pre-collector solenoid. This contribution reports on the design of the lens and presents the results of beam transport simulations for the electron beam (with space charge) and a representative ion beam, performed using the 3D CST STUDIO.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB384

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paper received ※ 20 May 2021 paper accepted ※ 05 July 2021 issue date ※ 31 August 2021

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THPAB157

Studying X-Ray Spectra of the SIS18 Electrostatic Septa to Measure Their Electric Field

4065

B. Gålander, E. Kozlova, D. Ondreka, A. Sokolov, P.J. Spiller, J. Stadlmann
GSI, Darmstadt, Germany

The synchrotron SIS18 at GSI uses resonant extraction for slow beam extraction on the order of seconds. For some time, there has been an unexplained discrepancy of the slow extraction with a lower extraction efficiency than expected at the highest beam energies. Recent machine studies have indicated that the deflection by the electrostatic septum might be less than the nominal 2.5 mrad, leading to increased losses at the magnetic septum. In this paper, we pursue an idea to directly measure the voltage of the electrode gap by utilizing the fact that dark current electrons accelerated in the gap of the electrostatic extraction septum generate Bremsstrahlung X-rays when hitting the anode. The high-energy cut-off of the X-ray spectra then corresponds to the voltage of the electrode gap. Measurements of the X-ray spectra at the extraction septum of SIS18 have been performed using a solid-state CdTe detector. This technique provides an in-situ measurement of the voltage applied to the electrostatic extraction channel and has proven to be a useful diagnostics tool.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB157

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paper received ※ 19 May 2021 paper accepted ※ 02 September 2021 issue date ※ 19 August 2021

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THPAB356

Progress and Status on Civil Construction of the SIS100 Accelerator Building

4493

M. Draisbach, N. Pyka, P.J. Spiller
GSI, Darmstadt, Germany
J. Blaurock, M. Ossendorf
FAIR, Darmstadt, Germany

Besides the accelerator machine itself, civil construction of the accelerator ring tunnel building in the northern area of the FAIR campus is a core activity of the rapidly progressing FAIR project. It will facilitate and supply the future SIS100 accelerator at 17m underground level and has been growing continuously and according to schedule since groundbreaking in 2017. This contribution presents the current status of the civil construction progress and gives an optimistic forecast for the preparation of machine installation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB356

About •

paper received ※ 20 May 2021 paper accepted ※ 06 July 2021 issue date ※ 15 August 2021

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