IPAC2021 - Classification: MC7: Accelerator Technology / T19 Collimation

Paper	Title	Page
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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WEPAB356	Proposal of an Alignment System for HALF: The Reference Network of Alignment	3533
	X. Li, J.X. Chen, X.Y. He, W. Wang, Z.Y. Wang USTC/NSRL, Hefei, Anhui, People’s Republic of China J.X. Chen, T. Luo IHEP CSNS, Guangdong Province, People’s Republic of China
	As a fourth-generation light source based on the diffraction-limited storage ring, Hefei Advanced Light Facility (HALF) has higher requirements for magnets alignment in accuracy, efficiency, and reliability. In this paper, the Reference Network of Alignment (RNA) system is proposed to improve the magnetic axis alignment accuracy on the radial direction of the beamline. Herein, we mainly introduce the concept design and the theoretical analysis of the RNA system, which center on the novel fusion method of sensors. A simulation result shows that it is credible to assume the RNA system can achieve an alignment installation accuracy of 20 µm and a displacement monitoring accuracy of 10 µm.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB356
About •	paper received ※ 16 May 2021 paper accepted ※ 21 June 2021 issue date ※ 31 August 2021
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WEPAB358	Development of Low-Z Collimator for SuperKEKB	3537
	S. Terui, T. Abe, Y. Funakoshi, T. Ishibashi, H.N. Nakayama, K. Ohmi, D. Zhou KEK, Ibaraki, Japan A. Natochii University of Hawaii, Honolulu,, USA
	Collimator jaws for SuperKEKB main ring, which is an electron-positron collider, installed to suppress background noise in a particle detector complex named Belle II. The collimators are successful to reduce backgrounds when the collimator was closed. But, in high current operations with 500 mA or more, jaws were occasionally damaged by hitting abnormal beams. This trouble is a low-frequency, which is once-a-commissioning period currently, but a high-consequence one because we are not able to apply high voltage on detectors in Belle II by high backgrounds. Low-Z collimator jaw, that is durable through hitting uncontrollable beam, have been designed due to protect important component as the solution of the trouble. The low-Z collimator jaws are installable in a present collimator chamber, have a pair of vertically opposed movable jaws. One pair of low-Z collimator jaws was installed. The paper is to describe what did we calculate and measure to make a low-Z collimator, how did we make a low-Z collimator, the impact of the installed low-Z collimator, mainly transverse mode coupling instability.
	Poster WEPAB358 [0.788 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB358
About •	paper received ※ 16 May 2021 paper accepted ※ 22 July 2021 issue date ※ 10 August 2021
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WEPAB360	Future Prospective for Bent Crystals in Accelerators	3545
	M. Romagnoni INFN-Ferrara, Ferrara, Italy M. Romagnoni Universita’ degli Studi di Milano, Milano, Italy
	Super magnet dipoles employed to steer high energy particle beams are massive instruments requiring cryogenic cooling and featuring large energy consumption. A bent crystal has the potential in a few millimeters to deflect 100-1000 GeV particle beams as much as an hundreds-tesla magnetic dipole. Indeed, within the lattice of a crystal, large electric fields up to several GeV/cm are present. Positive charged particles can be efficiently channeled between two adjacent lattice planes, thus following their curvature. These features and the possibility to selectively affect only the portion of the beam intercepting the crystal led to the proposal of exploiting bent crystals for several purposes, such as the collimation of ions at LHC. In this scheme, the particles on the beam halo instead of being scattered by tens-centimeters long collimators are directly separated from the beam using a 4 mm long silicon crystal. The production of a bent crystal suitable for installation in the LHC beamline requires strict control over lattice features and bending apparatus. The results obtained by the years long research of the INFN research team in Ferrara are presented in this work.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB360
About •	paper received ※ 14 May 2021 paper accepted ※ 28 July 2021 issue date ※ 18 August 2021
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WEPAB361	New Generation CERN LHC Injection Dump - Assembly and Installation (TDIS)	3548
	D. Carbajo Perez, E. Berthomé, C. Bertone, N. Biancacci, C. Bracco, G. Bregliozzi, B. Bulat, C. Cadiou, M. Calviani, G. Cattenoz, A. Cherif, P. Costa Pinto, A. Dallocchio, M. Di Castro, P. Fessia, M.I. Frankl, R. Franqueira Ximenes, J.-F. Fuchs, H. Garcia Gavela, J.-M. Geisser, L. Gentini, S.S. Gilardoni, M.A. Gonzalez De La Aleja Cabana, J.L. Grenard, J.M. Heredia, S. Joly, A. Lechner, J. Lendaro, J. Maestre, E. Page, M. Perez Ornedo, A. Perillo-Marcone, D. Pugnat, E. Rigutto, B. Salvant, A. Sapountzis, K. Scibor, R. Seidenbinder, J. Sola Merino, M. Taborelli, E. Urrutia, A. Vieille, C. Vollinger, C. Yin Vallgren CERN, Meyrin, Switzerland
	Funding: Work supported by the Hilumi Project During CERN’s LS2, several upgrades were performed to beam intercepting devices in the framework of the HL-LHC Project. Upgraded equipment includes two internal beam dumps (TDIS) intended for machine protection located at the injection points from the SPS to the LHC. These two devices have been assembled, tested, and installed around LHC Point 2 and Point 8 and are currently ready to get commissioned with the beam. They are 5.8m-long, three-module-segmented vacuum chambers, with large aperture to accommodate the injected and circulating beam and equipped with absorbing materials, These comprise graphite and higher Z alloys that are embedded on sub-assemblies reinforced with back-stiffeners made of TZM. The current contribution covers three main matters. First, it details the TDIS design and its key technical features. The second topic discussed is the outcome of an experiment where a prototype module was tested under high-energy beam impacts at CERN’s HiRadMat facility. To conclude it is presented the return of experience from the pre-series construction, validation and installation in the LHC tunnel.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB361
About •	paper received ※ 18 May 2021 paper accepted ※ 11 June 2021 issue date ※ 17 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

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)

WEPAB356

Proposal of an Alignment System for HALF: The Reference Network of Alignment

3533

X. Li, J.X. Chen, X.Y. He, W. Wang, Z.Y. Wang
USTC/NSRL, Hefei, Anhui, People’s Republic of China
J.X. Chen, T. Luo
IHEP CSNS, Guangdong Province, People’s Republic of China

As a fourth-generation light source based on the diffraction-limited storage ring, Hefei Advanced Light Facility (HALF) has higher requirements for magnets alignment in accuracy, efficiency, and reliability. In this paper, the Reference Network of Alignment (RNA) system is proposed to improve the magnetic axis alignment accuracy on the radial direction of the beamline. Herein, we mainly introduce the concept design and the theoretical analysis of the RNA system, which center on the novel fusion method of sensors. A simulation result shows that it is credible to assume the RNA system can achieve an alignment installation accuracy of 20 µm and a displacement monitoring accuracy of 10 µm.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB356

About •

paper received ※ 16 May 2021 paper accepted ※ 21 June 2021 issue date ※ 31 August 2021

Export •

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

WEPAB358

Development of Low-Z Collimator for SuperKEKB

3537

S. Terui, T. Abe, Y. Funakoshi, T. Ishibashi, H.N. Nakayama, K. Ohmi, D. Zhou
KEK, Ibaraki, Japan
A. Natochii
University of Hawaii, Honolulu,, USA

Collimator jaws for SuperKEKB main ring, which is an electron-positron collider, installed to suppress background noise in a particle detector complex named Belle II. The collimators are successful to reduce backgrounds when the collimator was closed. But, in high current operations with 500 mA or more, jaws were occasionally damaged by hitting abnormal beams. This trouble is a low-frequency, which is once-a-commissioning period currently, but a high-consequence one because we are not able to apply high voltage on detectors in Belle II by high backgrounds. Low-Z collimator jaw, that is durable through hitting uncontrollable beam, have been designed due to protect important component as the solution of the trouble. The low-Z collimator jaws are installable in a present collimator chamber, have a pair of vertically opposed movable jaws. One pair of low-Z collimator jaws was installed. The paper is to describe what did we calculate and measure to make a low-Z collimator, how did we make a low-Z collimator, the impact of the installed low-Z collimator, mainly transverse mode coupling instability.

Poster WEPAB358 [0.788 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB358

About •

paper received ※ 16 May 2021 paper accepted ※ 22 July 2021 issue date ※ 10 August 2021

Export •

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

WEPAB360

Future Prospective for Bent Crystals in Accelerators

3545

M. Romagnoni
INFN-Ferrara, Ferrara, Italy
M. Romagnoni
Universita’ degli Studi di Milano, Milano, Italy

Super magnet dipoles employed to steer high energy particle beams are massive instruments requiring cryogenic cooling and featuring large energy consumption. A bent crystal has the potential in a few millimeters to deflect 100-1000 GeV particle beams as much as an hundreds-tesla magnetic dipole. Indeed, within the lattice of a crystal, large electric fields up to several GeV/cm are present. Positive charged particles can be efficiently channeled between two adjacent lattice planes, thus following their curvature. These features and the possibility to selectively affect only the portion of the beam intercepting the crystal led to the proposal of exploiting bent crystals for several purposes, such as the collimation of ions at LHC. In this scheme, the particles on the beam halo instead of being scattered by tens-centimeters long collimators are directly separated from the beam using a 4 mm long silicon crystal. The production of a bent crystal suitable for installation in the LHC beamline requires strict control over lattice features and bending apparatus. The results obtained by the years long research of the INFN research team in Ferrara are presented in this work.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB360

About •

paper received ※ 14 May 2021 paper accepted ※ 28 July 2021 issue date ※ 18 August 2021

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

WEPAB361

New Generation CERN LHC Injection Dump - Assembly and Installation (TDIS)

3548

D. Carbajo Perez, E. Berthomé, C. Bertone, N. Biancacci, C. Bracco, G. Bregliozzi, B. Bulat, C. Cadiou, M. Calviani, G. Cattenoz, A. Cherif, P. Costa Pinto, A. Dallocchio, M. Di Castro, P. Fessia, M.I. Frankl, R. Franqueira Ximenes, J.-F. Fuchs, H. Garcia Gavela, J.-M. Geisser, L. Gentini, S.S. Gilardoni, M.A. Gonzalez De La Aleja Cabana, J.L. Grenard, J.M. Heredia, S. Joly, A. Lechner, J. Lendaro, J. Maestre, E. Page, M. Perez Ornedo, A. Perillo-Marcone, D. Pugnat, E. Rigutto, B. Salvant, A. Sapountzis, K. Scibor, R. Seidenbinder, J. Sola Merino, M. Taborelli, E. Urrutia, A. Vieille, C. Vollinger, C. Yin Vallgren
CERN, Meyrin, Switzerland

Funding: Work supported by the Hilumi Project
During CERN’s LS2, several upgrades were performed to beam intercepting devices in the framework of the HL-LHC Project. Upgraded equipment includes two internal beam dumps (TDIS) intended for machine protection located at the injection points from the SPS to the LHC. These two devices have been assembled, tested, and installed around LHC Point 2 and Point 8 and are currently ready to get commissioned with the beam. They are 5.8m-long, three-module-segmented vacuum chambers, with large aperture to accommodate the injected and circulating beam and equipped with absorbing materials, These comprise graphite and higher Z alloys that are embedded on sub-assemblies reinforced with back-stiffeners made of TZM. The current contribution covers three main matters. First, it details the TDIS design and its key technical features. The second topic discussed is the outcome of an experiment where a prototype module was tested under high-energy beam impacts at CERN’s HiRadMat facility. To conclude it is presented the return of experience from the pre-series construction, validation and installation in the LHC tunnel.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB361

About •

paper received ※ 18 May 2021 paper accepted ※ 11 June 2021 issue date ※ 17 August 2021

Export •

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