SRF2023 - List of Authors (Holzbauer, J.P.)

Paper	Title	Page
MOPMB081	Microphonics in the LCLS-II Superconducting Linac	302
	R.D. Porter, S. Aderhold, L.E. Alsberg, D. Gonnella, J. Nelson, N.R. Neveu, L.M. Zacarias SLAC, Menlo Park, California, USA A.T. Cravatta, J.P. Holzbauer, S. Posen Fermilab, Batavia, Illinois, USA M.A. Drury, M.D. McCaughan, C.M. Wilson JLab, Newport News, Virginia, USA G. Gaitan, N.A. Stilin Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by the LCLS-II project The LCLS-II project has installed a new superconducting linac at SLAC that consists of 35 1.3 GHz cryomodules and 2 3.9 GHz cryomodules. The linac will provide a 4 GeV electron beam for generating soft and hard X-ray pulses. Cavity detuning induced by microphonics was a significant design challenge for the LCLS-II cryomodules. Cryomodules were produced that were within the detuning specification (10 Hz for 1.3 GHz cryomodules) on test stands. Here we present first measurements of the microphonics in the installed LCLS-II superconducting linac. Overall, the microphonics in the linac are manageable with 94% of cavities coming within the detune specification. Only two cavities are gradient limited due to microphonics. We identify a leaking cool down valve as the source of microphonics limiting those two cavities.
	Poster MOPMB081 [1.284 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB081
About •	Received ※ 18 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 01 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB090	Measuring Q₀ in LCLS-II Cryomodules Using Helium Liquid Level	327
	L.M. Zacarias, S. Aderhold, D. Gonnella, J.T. Maniscalco, J. Nelson, R.D. Porter SLAC, Menlo Park, California, USA A.T. Cravatta, J.P. Holzbauer, S. Posen Fermilab, Batavia, Illinois, USA M.A. Drury, M.D. McCaughan, C.M. Wilson JLab, Newport News, Virginia, USA
	The nitrogen-doped cavities used in the Linac Coherent Light Source II (LCLS-II) cryomodules have shown an unprecedented high Q₀ in vertical and cryomodule testing compared with cavities prepared with standard methods. While demonstration of high Q₀ in the test stand has been achieved, maintaining that performance in the linac is critical to the success of LCLS-II and future accelerator projects. The LCLS-II cryomodules required a novel method of measuring Q₀, due to hardware incompatibilities with existing procedures. Initially developed at Jefferson Lab during cryomodule acceptance testing before being used in the tunnel at SLAC, we use helium liquid level data to estimate the heat generated by cavities. We first establish the relationship between the rate of helium evaporation from known heat loads using electric heaters, and then use that relationship to determine heat from an RF load. Here we present the full procedure along with the development process, lessons learned, and reproducibility while demonstrating for the first time that world record Q₀ can be maintained within the real accelerator environment.
	Poster MOPMB090 [1.867 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB090
About •	Received ※ 20 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 13 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPTB047	The Evaluation of Mechanical Properties of LB650 Cavities	536
	G. Wu, S.D. Adams, D.J. Bice, S.K. Chandrasekaran, I.V. Gonin, C.J. Grimm, J.P. Holzbauer, T.N. Khabiboulline, C.S. Narug, J.P. Ozelis, H. Park, G.V. Romanov, R. Thiede, R. Treece, A.D. Wixson Fermilab, Batavia, Illinois, USA K.E. McGee FRIB, East Lansing, Michigan, USA
	Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics. The 650 MHz cavities have a stronger requirement of niobium mechanical properties because of the geometric shape of the cavity due to reduced beta. The mechanical property of the niobium half-cell was measured following various heat treatments. The 5-cell cavities were tested in a controlled drop test fashion and the real-world road test. The result showed that the 900C heat treatment was compatible with cavity handling and transportation during production. The test provides the bases of the transportation specification and shipping container design guidelines.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB047
About •	Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 14 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPWB067	HB650 Cryomodule Design: From Prototype to Production	741
	V. Roger, S.K. Chandrasekaran, C.J. Grimm, J.P. Holzbauer, O. Napoly, J.P. Ozelis, D. Passarelli Fermilab, Batavia, Illinois, USA
	Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics. In early 2023 the assembly of the prototype HB650 cryomodule (pHB650 CM) was completed and cold tests started to evaluate its performance. The lessons learned from the design, assembly and preliminary cold tests of this cryomodule, and from the design of the SSR2 pre-production cryomodule played a fundamental role during the design optimization process of the production HB650 cryomodule (HB650 CM). Several workshops have been organized to share experiences and solve problems. This paper presents the main design changes from pHB650 to the HB650 production cryomodules and their impact on the heat loads.
	Poster WEPWB067 [2.178 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB067
About •	Received ※ 18 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 01 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPWB070	Test Shipment of the PIP-II 650 MHz Transport Frame Between FNAL to STFC-UKRI	750
	J.P. Holzbauer, S.K. Chandrasekaran, C.J. Grimm, J.P. Ozelis, R. Thiede, A.D. Wixson Fermilab, Batavia, Illinois, USA M.T.W. Kane STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy The PIP-II Project will receive fully assembled cryomodules from CEA and STFC-UKRI as in-kind contributions. Damage to these cryomodules during transport is understood to be a significant risk to the project, so an extensive testing and validation program is in process to mitigate this risk. The centerpiece of this effort is the eventual shipment from FNAL to STFC-UKRI and back of a prototype HB650 cryomodule with cold testing before and after shipment to verify no functionality changes from shipment. Most recently, a test shipment to the UK and back using a cryomodule analog was completed using realistic logistics, handling, instrumentation, and planning. The process of executing this test shipment, lessons learned, and plan moving forward will be presented here.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB070
About •	Received ※ 18 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 17 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPWB093	Transportation Fatigue Testing of the pHB650 Power Coupler Antenna for the PIP-II Project at Fermilab	801
	J. Helsper, S.K. Chandrasekaran, J.P. Holzbauer, N. Solyak Fermilab, Batavia, Illinois, USA
	Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics. The PIP-II Project will see international shipment of cryomodules from Europe to the United States, and as such, the shocks which can occur during shipment pose a risk to the internal components. Of particular concern is the coupler ceramic window and surrounding brazes, which can see relatively high stress during an excitation event. Since the antenna design is new, and because of the setback failure would create, a cyclic stress test was devised for the antenna. This paper presents the experimental methods, setup, and results of the test.
	Poster WEPWB093 [2.913 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB093
About •	Received ※ 19 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 03 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPWB096	Testing of PIP-II Pre-production 650 MHz Couplers in Warm Test Stand and Cryomodule	812
	N. Solyak, S.K. Chandrasekaran, B.M. Hanna, J. Helsper, J.P. Holzbauer, S. Kazakov, A.I. Sukhanov Fermilab, Batavia, Illinois, USA
	650 MHz fundamental power couplers were developed for PIP-II project to deliver RF power for low-beta and high-beta elliptical cavities. Few prototypes were built and tested and after some modification we built 8 pre-production couplers (with three spares for vacuum side) for ppHB650 cryomodule. All couplers were successfully tested in pulse mode (up to 100kW) and in CW mode (up to 50kW) in test stand at full reflection at 8 phases. In baseline configuration with DC bias we do not see any multipactoring activity after short processing. We also tested power processing without bias for uncoated and TiN coated ceramic window. Results of these studies presented in this paper. One of the coupler was assembled on LB650 cavity and tested at cryogenic environment in STC cryostat at ~30kW power with full reflection at different reflection phase. We also demonstrated good result from power processing without bias for warm and cold cavity. Six couplers were assembled on HB650 cavities in pre-production cryomodule. Test results from cryomodule qualification is discussing in this paper.
	Poster WEPWB096 [2.748 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB096
About •	Received ※ 19 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 17 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Microphonics in the LCLS-II Superconducting Linac

302

R.D. Porter, S. Aderhold, L.E. Alsberg, D. Gonnella, J. Nelson, N.R. Neveu, L.M. Zacarias
SLAC, Menlo Park, California, USA
A.T. Cravatta, J.P. Holzbauer, S. Posen
Fermilab, Batavia, Illinois, USA
M.A. Drury, M.D. McCaughan, C.M. Wilson
JLab, Newport News, Virginia, USA
G. Gaitan, N.A. Stilin
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by the LCLS-II project
The LCLS-II project has installed a new superconducting linac at SLAC that consists of 35 1.3 GHz cryomodules and 2 3.9 GHz cryomodules. The linac will provide a 4 GeV electron beam for generating soft and hard X-ray pulses. Cavity detuning induced by microphonics was a significant design challenge for the LCLS-II cryomodules. Cryomodules were produced that were within the detuning specification (10 Hz for 1.3 GHz cryomodules) on test stands. Here we present first measurements of the microphonics in the installed LCLS-II superconducting linac. Overall, the microphonics in the linac are manageable with 94% of cavities coming within the detune specification. Only two cavities are gradient limited due to microphonics. We identify a leaking cool down valve as the source of microphonics limiting those two cavities.

Poster MOPMB081 [1.284 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB081

About •

Received ※ 18 June 2023 — Revised ※ 29 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 01 July 2023

Cite •

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

MOPMB090

Measuring Q₀ in LCLS-II Cryomodules Using Helium Liquid Level

327

L.M. Zacarias, S. Aderhold, D. Gonnella, J.T. Maniscalco, J. Nelson, R.D. Porter
SLAC, Menlo Park, California, USA
A.T. Cravatta, J.P. Holzbauer, S. Posen
Fermilab, Batavia, Illinois, USA
M.A. Drury, M.D. McCaughan, C.M. Wilson
JLab, Newport News, Virginia, USA

The nitrogen-doped cavities used in the Linac Coherent Light Source II (LCLS-II) cryomodules have shown an unprecedented high Q₀ in vertical and cryomodule testing compared with cavities prepared with standard methods. While demonstration of high Q₀ in the test stand has been achieved, maintaining that performance in the linac is critical to the success of LCLS-II and future accelerator projects. The LCLS-II cryomodules required a novel method of measuring Q₀, due to hardware incompatibilities with existing procedures. Initially developed at Jefferson Lab during cryomodule acceptance testing before being used in the tunnel at SLAC, we use helium liquid level data to estimate the heat generated by cavities. We first establish the relationship between the rate of helium evaporation from known heat loads using electric heaters, and then use that relationship to determine heat from an RF load. Here we present the full procedure along with the development process, lessons learned, and reproducibility while demonstrating for the first time that world record Q₀ can be maintained within the real accelerator environment.

Poster MOPMB090 [1.867 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB090

About •

Received ※ 20 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 30 June 2023 — Issue date ※ 13 July 2023

Cite •

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

TUPTB047

The Evaluation of Mechanical Properties of LB650 Cavities

536

G. Wu, S.D. Adams, D.J. Bice, S.K. Chandrasekaran, I.V. Gonin, C.J. Grimm, J.P. Holzbauer, T.N. Khabiboulline, C.S. Narug, J.P. Ozelis, H. Park, G.V. Romanov, R. Thiede, R. Treece, A.D. Wixson
Fermilab, Batavia, Illinois, USA
K.E. McGee
FRIB, East Lansing, Michigan, USA

Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
The 650 MHz cavities have a stronger requirement of niobium mechanical properties because of the geometric shape of the cavity due to reduced beta. The mechanical property of the niobium half-cell was measured following various heat treatments. The 5-cell cavities were tested in a controlled drop test fashion and the real-world road test. The result showed that the 900C heat treatment was compatible with cavity handling and transportation during production. The test provides the bases of the transportation specification and shipping container design guidelines.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB047

About •

Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 14 July 2023

Cite •

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

WEPWB067

HB650 Cryomodule Design: From Prototype to Production

741

V. Roger, S.K. Chandrasekaran, C.J. Grimm, J.P. Holzbauer, O. Napoly, J.P. Ozelis, D. Passarelli
Fermilab, Batavia, Illinois, USA

Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
In early 2023 the assembly of the prototype HB650 cryomodule (pHB650 CM) was completed and cold tests started to evaluate its performance. The lessons learned from the design, assembly and preliminary cold tests of this cryomodule, and from the design of the SSR2 pre-production cryomodule played a fundamental role during the design optimization process of the production HB650 cryomodule (HB650 CM). Several workshops have been organized to share experiences and solve problems. This paper presents the main design changes from pHB650 to the HB650 production cryomodules and their impact on the heat loads.

Poster WEPWB067 [2.178 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB067

About •

Received ※ 18 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 01 July 2023

Cite •

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

WEPWB070

Test Shipment of the PIP-II 650 MHz Transport Frame Between FNAL to STFC-UKRI

750

J.P. Holzbauer, S.K. Chandrasekaran, C.J. Grimm, J.P. Ozelis, R. Thiede, A.D. Wixson
Fermilab, Batavia, Illinois, USA
M.T.W. Kane
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Funding: Work supported by Fermi Research Alliance, LLC under Contract No. DEAC02- 07CH11359 with the United States Department of Energy
The PIP-II Project will receive fully assembled cryomodules from CEA and STFC-UKRI as in-kind contributions. Damage to these cryomodules during transport is understood to be a significant risk to the project, so an extensive testing and validation program is in process to mitigate this risk. The centerpiece of this effort is the eventual shipment from FNAL to STFC-UKRI and back of a prototype HB650 cryomodule with cold testing before and after shipment to verify no functionality changes from shipment. Most recently, a test shipment to the UK and back using a cryomodule analog was completed using realistic logistics, handling, instrumentation, and planning. The process of executing this test shipment, lessons learned, and plan moving forward will be presented here.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB070

About •

Received ※ 18 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 17 July 2023

Cite •

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

WEPWB093

Transportation Fatigue Testing of the pHB650 Power Coupler Antenna for the PIP-II Project at Fermilab

801

J. Helsper, S.K. Chandrasekaran, J.P. Holzbauer, N. Solyak
Fermilab, Batavia, Illinois, USA

Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
The PIP-II Project will see international shipment of cryomodules from Europe to the United States, and as such, the shocks which can occur during shipment pose a risk to the internal components. Of particular concern is the coupler ceramic window and surrounding brazes, which can see relatively high stress during an excitation event. Since the antenna design is new, and because of the setback failure would create, a cyclic stress test was devised for the antenna. This paper presents the experimental methods, setup, and results of the test.

Poster WEPWB093 [2.913 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB093

About •

Received ※ 19 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 03 July 2023

Cite •

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

WEPWB096

Testing of PIP-II Pre-production 650 MHz Couplers in Warm Test Stand and Cryomodule

812

N. Solyak, S.K. Chandrasekaran, B.M. Hanna, J. Helsper, J.P. Holzbauer, S. Kazakov, A.I. Sukhanov
Fermilab, Batavia, Illinois, USA

650 MHz fundamental power couplers were developed for PIP-II project to deliver RF power for low-beta and high-beta elliptical cavities. Few prototypes were built and tested and after some modification we built 8 pre-production couplers (with three spares for vacuum side) for ppHB650 cryomodule. All couplers were successfully tested in pulse mode (up to 100kW) and in CW mode (up to 50kW) in test stand at full reflection at 8 phases. In baseline configuration with DC bias we do not see any multipactoring activity after short processing. We also tested power processing without bias for uncoated and TiN coated ceramic window. Results of these studies presented in this paper. One of the coupler was assembled on LB650 cavity and tested at cryogenic environment in STC cryostat at ~30kW power with full reflection at different reflection phase. We also demonstrated good result from power processing without bias for warm and cold cavity. Six couplers were assembled on HB650 cavities in pre-production cryomodule. Test results from cryomodule qualification is discussing in this paper.

Poster WEPWB096 [2.748 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB096

About •

Received ※ 19 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 17 July 2023

Cite •

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