IPAC2018 - List of Authors (Laxdal, R.E.)

Paper	Title	Page
MOXGB2	ARIEL at TRIUMF: Science and Technology	6
	J.A. Bagger, F. Ames, Y. Bylinskii, A. Gottberg, O.K. Kester, S.R. Koscielniak, R.E. Laxdal, M. Marchetto, P. Schaffer TRIUMF, Vancouver, Canada M. Hayashi TRIUMF Innovations Inc., Vancouver, Canada
	The Advanced Rare Isotope Laboratory (ARIEL) is TRIUMF's flagship project to create isotopes for science, medicine and business. ARIEL will triple TRIUMF's rare isotope beam capability, enabling more and new experiments in materials science, nuclear physics, nuclear astrophysics, and fundamental symmetries, as well as the development of new isotopes for the life sciences. Beams from ARIEL's new 35 MeV, 100kW electron linear accelerator and from TRIUMF's original 500 MeV cyclotron will enable breakthrough experiments with the laboratory's suite of world-class experiments at the Isotope Separator and Accelerator (ISAC) facility. This invited talk will present an overview of TRIUMF, the ARIEL project, and the exciting science they enable.
	Slides MOXGB2 [65.004 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOXGB2
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TUPAL037	Installation Progress on FRIB β=0.041 Cryomodules Toward Beam Commissioning	1087
	H. Ao, B. Bird, N.K. Bultman, F. Casagrande, C. Compton, K.D. Davidson, K. Elliott, V. Ganni, A. Ganshyn, P.E. Gibson, I. Grender, W. Hartung, L. Hodges, K. Holland, A. Hussain, M. Ikegami, S. Jones, P. Knudsen, S.M. Lidia, I.M. Malloch, E.S. Metzgar, S.J. Miller, D.G. Morris, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, M.A. Reaume, T. Russo, K. Saito, M. Shuptar, S. Stanley, S. Stark, D.R. Victory, J. Wei, J.D. Wenstrom, M. Xu, T. Xu, Y. Xu, Y. Yamazaki, Q. Zhao, S. Zhao FRIB, East Lansing, USA A. Facco INFN/LNL, Legnaro (PD), Italy R.E. Laxdal TRIUMF, Vancouver, Canada M. Wiseman JLab, Newport News, Virginia, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 The Facility for Rare Isotope Beams (FRIB) driver linac is to accelerate all the stable ion beams from proton to uranium beyond 200 MeV/u with beam powers up to 400 kW, which will be the first large-scale, CW SRF ion linac. The beam commissioning of the front end (from the ion source to the RFQ) already began and is in progress. The Accelerator Readiness Review (ARR) for beam through the first three β=0.041 cryomodules is scheduled for May 2018. The next step is the beam commissioning through the 12 SRF cavities housed in these 3 cryomodules with 6 superconducting solenoid magnets. The cryomodules and the adjacent warm diagnostics boxes in between have been already installed and aligned in the tunnel. This paper describes the installation progress of the β=0.041 cryomodules and plans for ARR02.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL037
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THPAL120	Cryogenics Infrastructure at TRIUMF's Particle Accelerator Facilities	3925
	A.N. Koveshnikov, Y. Bylinskii, G.W. Hodgson, D. Kishi, R.E. Laxdal, R.R. Nagimov, D. Yosifov TRIUMF, Vancouver, Canada
	Funding: TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada. Cryogenic infrastructure is an indispensable part of TRIUMF accelerator facilities. At the moment TRIUMF operates three helium cryogenic systems supporting operation of three major accelerator systems: 520 MeV proton cyclotron, superconductive radio-frequency (SRF) heavy ion linear accelerator at the Rare Isotope Beams (RIB) facility, and SRF electron linear accelerator (e-linac) at Advanced Rare IsotopE Laboratory (ARIEL). Applications of cryogenic thermal loads vary from cryogenic absorption pumping of the cyclotron vacuum tank to cryogenic cooling of superconducting (SC) RF cavities of production accelerators and support of research and development at SRF department. Wide range of production techniques for cryogenic refrigeration includes helium refrigerators based on both piston and turbine expansion coldboxes for both 4 K and 2 K temperature cryogenic loads. This paper presents the details of TRIUMF cryogenic systems as well as operational experience of various cryogenic installations.
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THPAL121	The Operational Experience of E-Linac Cryogenic System at TRIUMF	3928
	R.R. Nagimov, Y. Bylinskii, D. Kishi, S.R. Koscielniak, A.N. Koveshnikov, R.E. Laxdal, D. Yosifov TRIUMF, Vancouver, Canada
	Funding: ARIEL is funded by CFI, the Provinces of AB, BC, MA, ON, QC, and TRIUMF. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada. The new Advanced Rare IsotopE Laboratory (ARIEL) is a major expansion of the Rare Isotope Beams (RIB) facility at TRIUMF. Superconducting radio-frequency (SRF) cavities cooled down to 2 K are the key part of ARIEL electron linear accelerator (e-linac). Design of the cryogenic system was bound to follow both phased project schedule and existing building infrastructure. Due to the scheduling of commissioning and R&D activities of ARIEL project, high availability requirements were set for e-linac cryogenic system during its commissioning stage. Various upgrades were introduced during system commissioning in order to improve overall availability and reliability of the system. This paper presents the details of operational experience, commissioning activities and continuous improvement of various operational aspects of e-linac cryogenic system.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL121
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THPAL122	Beam Performance Study of an RF Structure to Accelerate or Bunch Low Energy Ion Beams	3931
	S.D. Rädel, S. Kiy, R.E. Laxdal, O. Shelbaya TRIUMF, Vancouver, Canada
	The 35.4MHz Radio Frequency Quadrupole (RFQ) at the ISAC-I facility at TRIUMF is designed to accelerate ions from an energy of 2.04 keV/u to 150 keV/u for a large range of mass-to-charge ratios (A/Q). A multi-harmonic, 11.8MHz, buncher is used to provide a time focus at the RFQ entrance. Due to limits in the ion source HV platform a boost in the energy is required for higher mass beams (20 ≤ A/Q ≤ 30) to provide energy matching into the RFQ. To achieve this, a 3-gap, 11.8 MHz RF booster has been installed into the ISAC-I facility downstream of the buncher and upstream of the RFQ. The device can operate as an accelerator to match into the RFQ or as a second pre-buncher to improve capture in the RFQ and reduce sensitivity to space charge. Proof-of-principle measurements demonstrating various aspects of the performance will be reported and compared against expectations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL122
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THPAL123	Fabrication and Test of β=0.3 325MHz Balloon Single Spoke Resonator	3934
	Z.Y. Yao, J.J. Keir, D. Kishi, D. Lang, R.E. Laxdal, H.L. Liu, Y. Ma, B. Matheson, B.S. Waraich, Q. Zheng, V. Zvyagintsev TRIUMF, Vancouver, Canada
	A novel balloon variant of the single spoke resonator (SSR) has been designed, fabricated and tested at TRIUMF. The cavity is the β=0.3 325 MHz SSR1 prototype for the Rare Isotope Science Project (RISP) in Korea. The balloon variant is specifically designed to reduce the likelihood of multipacting barriers near the operating point. A systematic multipacting study led to a novel geometry, a spherical cavity with re-entrant irises plus a spoke. The balloon cavity provides competitive RF parameters and a robust mechanical structure. Cold tests demonstrated the principle of the balloon concept. The fabrication experience and the preliminary test results will be reported in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL123
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THPMK090	First RF Test Results of Two-Cavities Accelerating Cryomodule for ARIEL eLinac at TRIUMF	4512
	Y. Ma, Z.T. Ang, K. Fong, J.J. Keir, D. Kishi, D. Lang, R.E. Laxdal, R.R. Nagimov, B.S. Waraich, Z.Y. Yao, V. Zvyagintsev TRIUMF, Vancouver, Canada
	The Advanced Rare Isotope Laboratory (ARIEL) pro-ject requires a 50 MeV, 10 mA continuous-wave (CW) electron linear accelerator (e-Linac) as a driver accelera-tor. Now the stage of the 30MeV portion of the e-Linac is under commissioning which includes an injector cry-omodule(ICM) and the 1st accelerator cryomodules (ACM1) with two cavities configuration. A single 290kW klystron is used to feed the two ACM1 cavities in vector sum closed-loop control. In this paper the initial commis-sioning results of the ACM1 RF system will be present.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK090
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THPML081	Beam-Based Measurements of the ISAC-II Superconducting Heavy Ion Linac	4841
	S. Kiy, R.E. Laxdal, M. Marchetto, S.D. Rädel, O. Shelbaya TRIUMF, Vancouver, Canada
	Preparation for experiments, which typically run for one to two weeks in the ISAC-II facility at TRIUMF, requires some amount of overhead, limiting the efficiency of the facility. Efforts are underway to improve the ISAC-II linac model to reduce this overhead while also improving the quality of the delivered ion beam. This can be accomplished with beam-based measurements and corrections of alignment, cavity gradients, focal strengths, and more. A review of the present state of the linac will be given, including measured mis-alignments and other factors that affect the reproducibility of tunes. The outlook on expected improvements will also be summarized, including progress on the automatic phasing of cavities with a focus on integration to the High Level Application platform being developed at TRIUMF. Lastly, a summary will be given on the expected paradigm shift in the tuning approach taken: moving from re-active tuning by operators or beam delivery experts to pro-active measurements and investigations, version-controlled tunes, and continuous feedback from beam physicists.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML081
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THPML122	Beta-SRF - A New Facility to Characterize SRF Materials near Fundamental Limits	4961
SUSPL077	use link to see paper's listing under its alternate paper code
	E. Thoeng UBC & TRIUMF, Vancouver, British Columbia, Canada R.A. Baartman, R.E. Laxdal, B. Matheson, G. Morris, N. Muller, S. Saminathan TRIUMF, Vancouver, Canada A. Chen UBC, Vancouver, Canada T. Junginger Lancaster University, Lancaster, United Kingdom
	Funding: Natural Sciences and Engineering Research Council of Canada (NSERC) & UBC (NSERC) IsoSiM Program Demands of CW high-power LINAC require SRF cavities operating at the frontier of high accelerating gradient and low RF power dissipation, i.e. high quality factor (Q₀). This requirement poses a challenge for standard surface treatment recipes of SRF cavities. In a recent breakthrough, elliptical SRF cavities doped with Nitrogen have been shown to improve Q₀ by a factor of 3, close to the fundamental SRF limit. The fundamental mechanisms at microscopic level and optimum doping recipe, however, have still not fully been understood. Materials other than Nb have also been proposed for SRF cavities to overcome the fundamental limit already reached with Nitrogen doping, e.g. Nb₃Sn, MgB₂, and Nb-SIS multilayer. At TRIUMF, a unique experimental facility is currently being developed to address these issues. This facility will be able to probe local surface magnetic field in the order of the London Penetration Depth (several tens of nm) via \beta decay detection of a low-energy radioactive ion-beam. This allows depth-resolution and layer-by-layer measurement of magnetic field shielding effectiveness of different SRF materials at high-parallel field (up to 200 mT). Design and current development of this facility will be presented here, as well as commissioning and future measurements strategies for new SRF materials.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML122
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THPML132	Cryogenic Performance of an SRF Deflecting Cavity Fabricated Using Alternative Techniques for the ARIEL eLinac	4992
	D.W. Storey Victoria University, Victoria, B.C., Canada R.E. Laxdal, Z.Y. Yao TRIUMF, Vancouver, Canada
	A 650 MHz SRF deflecting mode cavity has been built and tested for use as a three-way beam separator in the ARIEL eLinac. The cavity operates in a TE-like mode, and has been optimized for high shunt impedance with minimal longitudinal footprint. The device is the first SRF cavity to be fully fabricated in house at TRIUMF. The requirements of the cavity allowed for the development of low cost manufacturing techniques, including the use of Reactor grade niobium and atmospheric pressure TIG welding. The cavity has been fabricated and tested at 4 K and 2 K, obtaining a 4 K Qo of 4·10⁸ at the operating voltage of 0.3 MV, surpassing the goal voltage and quality factor required for operation. Results of the cryogenic tests of the cavity will be presented here.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML132
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Paper

Title

Page

ARIEL at TRIUMF: Science and Technology

6

J.A. Bagger, F. Ames, Y. Bylinskii, A. Gottberg, O.K. Kester, S.R. Koscielniak, R.E. Laxdal, M. Marchetto, P. Schaffer
TRIUMF, Vancouver, Canada
M. Hayashi
TRIUMF Innovations Inc., Vancouver, Canada

The Advanced Rare Isotope Laboratory (ARIEL) is TRIUMF's flagship project to create isotopes for science, medicine and business. ARIEL will triple TRIUMF's rare isotope beam capability, enabling more and new experiments in materials science, nuclear physics, nuclear astrophysics, and fundamental symmetries, as well as the development of new isotopes for the life sciences. Beams from ARIEL's new 35 MeV, 100kW electron linear accelerator and from TRIUMF's original 500 MeV cyclotron will enable breakthrough experiments with the laboratory's suite of world-class experiments at the Isotope Separator and Accelerator (ISAC) facility. This invited talk will present an overview of TRIUMF, the ARIEL project, and the exciting science they enable.

Slides MOXGB2 [65.004 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOXGB2

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TUPAL037

Installation Progress on FRIB β=0.041 Cryomodules Toward Beam Commissioning

1087

H. Ao, B. Bird, N.K. Bultman, F. Casagrande, C. Compton, K.D. Davidson, K. Elliott, V. Ganni, A. Ganshyn, P.E. Gibson, I. Grender, W. Hartung, L. Hodges, K. Holland, A. Hussain, M. Ikegami, S. Jones, P. Knudsen, S.M. Lidia, I.M. Malloch, E.S. Metzgar, S.J. Miller, D.G. Morris, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, M.A. Reaume, T. Russo, K. Saito, M. Shuptar, S. Stanley, S. Stark, D.R. Victory, J. Wei, J.D. Wenstrom, M. Xu, T. Xu, Y. Xu, Y. Yamazaki, Q. Zhao, S. Zhao
FRIB, East Lansing, USA
A. Facco
INFN/LNL, Legnaro (PD), Italy
R.E. Laxdal
TRIUMF, Vancouver, Canada
M. Wiseman
JLab, Newport News, Virginia, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The Facility for Rare Isotope Beams (FRIB) driver linac is to accelerate all the stable ion beams from proton to uranium beyond 200 MeV/u with beam powers up to 400 kW, which will be the first large-scale, CW SRF ion linac. The beam commissioning of the front end (from the ion source to the RFQ) already began and is in progress. The Accelerator Readiness Review (ARR) for beam through the first three β=0.041 cryomodules is scheduled for May 2018. The next step is the beam commissioning through the 12 SRF cavities housed in these 3 cryomodules with 6 superconducting solenoid magnets. The cryomodules and the adjacent warm diagnostics boxes in between have been already installed and aligned in the tunnel. This paper describes the installation progress of the β=0.041 cryomodules and plans for ARR02.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL037

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THPAL120

Cryogenics Infrastructure at TRIUMF's Particle Accelerator Facilities

3925

A.N. Koveshnikov, Y. Bylinskii, G.W. Hodgson, D. Kishi, R.E. Laxdal, R.R. Nagimov, D. Yosifov
TRIUMF, Vancouver, Canada

Funding: TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada.
Cryogenic infrastructure is an indispensable part of TRIUMF accelerator facilities. At the moment TRIUMF operates three helium cryogenic systems supporting operation of three major accelerator systems: 520 MeV proton cyclotron, superconductive radio-frequency (SRF) heavy ion linear accelerator at the Rare Isotope Beams (RIB) facility, and SRF electron linear accelerator (e-linac) at Advanced Rare IsotopE Laboratory (ARIEL). Applications of cryogenic thermal loads vary from cryogenic absorption pumping of the cyclotron vacuum tank to cryogenic cooling of superconducting (SC) RF cavities of production accelerators and support of research and development at SRF department. Wide range of production techniques for cryogenic refrigeration includes helium refrigerators based on both piston and turbine expansion coldboxes for both 4 K and 2 K temperature cryogenic loads. This paper presents the details of TRIUMF cryogenic systems as well as operational experience of various cryogenic installations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL120

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THPAL121

The Operational Experience of E-Linac Cryogenic System at TRIUMF

3928

R.R. Nagimov, Y. Bylinskii, D. Kishi, S.R. Koscielniak, A.N. Koveshnikov, R.E. Laxdal, D. Yosifov
TRIUMF, Vancouver, Canada

Funding: ARIEL is funded by CFI, the Provinces of AB, BC, MA, ON, QC, and TRIUMF. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada.
The new Advanced Rare IsotopE Laboratory (ARIEL) is a major expansion of the Rare Isotope Beams (RIB) facility at TRIUMF. Superconducting radio-frequency (SRF) cavities cooled down to 2 K are the key part of ARIEL electron linear accelerator (e-linac). Design of the cryogenic system was bound to follow both phased project schedule and existing building infrastructure. Due to the scheduling of commissioning and R&D activities of ARIEL project, high availability requirements were set for e-linac cryogenic system during its commissioning stage. Various upgrades were introduced during system commissioning in order to improve overall availability and reliability of the system. This paper presents the details of operational experience, commissioning activities and continuous improvement of various operational aspects of e-linac cryogenic system.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL121

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THPAL122

Beam Performance Study of an RF Structure to Accelerate or Bunch Low Energy Ion Beams

3931

S.D. Rädel, S. Kiy, R.E. Laxdal, O. Shelbaya
TRIUMF, Vancouver, Canada

The 35.4MHz Radio Frequency Quadrupole (RFQ) at the ISAC-I facility at TRIUMF is designed to accelerate ions from an energy of 2.04 keV/u to 150 keV/u for a large range of mass-to-charge ratios (A/Q). A multi-harmonic, 11.8MHz, buncher is used to provide a time focus at the RFQ entrance. Due to limits in the ion source HV platform a boost in the energy is required for higher mass beams (20 ≤ A/Q ≤ 30) to provide energy matching into the RFQ. To achieve this, a 3-gap, 11.8 MHz RF booster has been installed into the ISAC-I facility downstream of the buncher and upstream of the RFQ. The device can operate as an accelerator to match into the RFQ or as a second pre-buncher to improve capture in the RFQ and reduce sensitivity to space charge. Proof-of-principle measurements demonstrating various aspects of the performance will be reported and compared against expectations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL122

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THPAL123

Fabrication and Test of β=0.3 325MHz Balloon Single Spoke Resonator

3934

Z.Y. Yao, J.J. Keir, D. Kishi, D. Lang, R.E. Laxdal, H.L. Liu, Y. Ma, B. Matheson, B.S. Waraich, Q. Zheng, V. Zvyagintsev
TRIUMF, Vancouver, Canada

A novel balloon variant of the single spoke resonator (SSR) has been designed, fabricated and tested at TRIUMF. The cavity is the β=0.3 325 MHz SSR1 prototype for the Rare Isotope Science Project (RISP) in Korea. The balloon variant is specifically designed to reduce the likelihood of multipacting barriers near the operating point. A systematic multipacting study led to a novel geometry, a spherical cavity with re-entrant irises plus a spoke. The balloon cavity provides competitive RF parameters and a robust mechanical structure. Cold tests demonstrated the principle of the balloon concept. The fabrication experience and the preliminary test results will be reported in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL123

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THPMK090

First RF Test Results of Two-Cavities Accelerating Cryomodule for ARIEL eLinac at TRIUMF

4512

Y. Ma, Z.T. Ang, K. Fong, J.J. Keir, D. Kishi, D. Lang, R.E. Laxdal, R.R. Nagimov, B.S. Waraich, Z.Y. Yao, V. Zvyagintsev
TRIUMF, Vancouver, Canada

The Advanced Rare Isotope Laboratory (ARIEL) pro-ject requires a 50 MeV, 10 mA continuous-wave (CW) electron linear accelerator (e-Linac) as a driver accelera-tor. Now the stage of the 30MeV portion of the e-Linac is under commissioning which includes an injector cry-omodule(ICM) and the 1st accelerator cryomodules (ACM1) with two cavities configuration. A single 290kW klystron is used to feed the two ACM1 cavities in vector sum closed-loop control. In this paper the initial commis-sioning results of the ACM1 RF system will be present.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK090

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THPML081

Beam-Based Measurements of the ISAC-II Superconducting Heavy Ion Linac

4841

S. Kiy, R.E. Laxdal, M. Marchetto, S.D. Rädel, O. Shelbaya
TRIUMF, Vancouver, Canada

Preparation for experiments, which typically run for one to two weeks in the ISAC-II facility at TRIUMF, requires some amount of overhead, limiting the efficiency of the facility. Efforts are underway to improve the ISAC-II linac model to reduce this overhead while also improving the quality of the delivered ion beam. This can be accomplished with beam-based measurements and corrections of alignment, cavity gradients, focal strengths, and more. A review of the present state of the linac will be given, including measured mis-alignments and other factors that affect the reproducibility of tunes. The outlook on expected improvements will also be summarized, including progress on the automatic phasing of cavities with a focus on integration to the High Level Application platform being developed at TRIUMF. Lastly, a summary will be given on the expected paradigm shift in the tuning approach taken: moving from re-active tuning by operators or beam delivery experts to pro-active measurements and investigations, version-controlled tunes, and continuous feedback from beam physicists.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML081

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THPML122

Beta-SRF - A New Facility to Characterize SRF Materials near Fundamental Limits

4961

SUSPL077

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

E. Thoeng
UBC & TRIUMF, Vancouver, British Columbia, Canada
R.A. Baartman, R.E. Laxdal, B. Matheson, G. Morris, N. Muller, S. Saminathan
TRIUMF, Vancouver, Canada
A. Chen
UBC, Vancouver, Canada
T. Junginger
Lancaster University, Lancaster, United Kingdom

Funding: Natural Sciences and Engineering Research Council of Canada (NSERC) & UBC (NSERC) IsoSiM Program
Demands of CW high-power LINAC require SRF cavities operating at the frontier of high accelerating gradient and low RF power dissipation, i.e. high quality factor (Q₀). This requirement poses a challenge for standard surface treatment recipes of SRF cavities. In a recent breakthrough, elliptical SRF cavities doped with Nitrogen have been shown to improve Q₀ by a factor of 3, close to the fundamental SRF limit. The fundamental mechanisms at microscopic level and optimum doping recipe, however, have still not fully been understood. Materials other than Nb have also been proposed for SRF cavities to overcome the fundamental limit already reached with Nitrogen doping, e.g. Nb₃Sn, MgB₂, and Nb-SIS multilayer. At TRIUMF, a unique experimental facility is currently being developed to address these issues. This facility will be able to probe local surface magnetic field in the order of the London Penetration Depth (several tens of nm) via \beta decay detection of a low-energy radioactive ion-beam. This allows depth-resolution and layer-by-layer measurement of magnetic field shielding effectiveness of different SRF materials at high-parallel field (up to 200 mT). Design and current development of this facility will be presented here, as well as commissioning and future measurements strategies for new SRF materials.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML122

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THPML132

Cryogenic Performance of an SRF Deflecting Cavity Fabricated Using Alternative Techniques for the ARIEL eLinac

4992

D.W. Storey
Victoria University, Victoria, B.C., Canada
R.E. Laxdal, Z.Y. Yao
TRIUMF, Vancouver, Canada

A 650 MHz SRF deflecting mode cavity has been built and tested for use as a three-way beam separator in the ARIEL eLinac. The cavity operates in a TE-like mode, and has been optimized for high shunt impedance with minimal longitudinal footprint. The device is the first SRF cavity to be fully fabricated in house at TRIUMF. The requirements of the cavity allowed for the development of low cost manufacturing techniques, including the use of Reactor grade niobium and atmospheric pressure TIG welding. The cavity has been fabricated and tested at 4 K and 2 K, obtaining a 4 K Qo of 4·10⁸ at the operating voltage of 0.3 MV, surpassing the goal voltage and quality factor required for operation. Results of the cryogenic tests of the cavity will be presented here.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML132

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