Paper | Title | Page |
---|---|---|
MOOHC2 | The US Electron Ion Collider Accelerator Designs | 1 |
|
||
With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collider, the prospects for construction of such a facility have taken a step forward. This paper provides an overview of the two site-specific EIC designs: JLEIC (Jefferson Lab) and eRHIC (BNL) as well as brief overview of ongoing EIC R&D. | ||
![]() |
Slides MOOHC2 [14.774 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOOHC2 | |
About • | paper received ※ 29 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEZBA2 | Experience and Lessons in FRIB Superconducting Quarter-Wave Resonator Commissioning | 646 |
|
||
The superconducting (SC) linear accelerator (linac) for the Facility for Rare Isotope Beams (FRIB) has one quarter-wave resonator (QWR) segment and two half-wave resonator (HWR) segments. The first linac segment (LS1) contains twelve β = 0.041 and ninety-two β = 0.085 QWRs operating at 80.5 MHz, and thirty-nine SC solenoids. Superconducting radiofrequency (SRF) commissioning and beam commissioning of LS1 was completed in April 2019. The design accelerating gradients (5.1 MV/m for β = 0.041 and 5.6 MV/m for β = 0.085) were achieved in all cavities with no multipacting or field emission issues. The cavity field met the design goals: peak-to-peak stability of ±1% in amplitude and ±1° in phase. We achieved 20.3 MeV/u ion beams of Ar, Kr, Ne, and Xe with LS1. In this paper, we will discuss lessons learned from the SRF commissioning of the cryomodules and methods developed for efficient testing, conditioning, and commissioning of more than 100 SC cavities, each with its own independent RF system. | ||
![]() |
Slides WEZBA2 [2.841 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEZBA2 | |
About • | paper received ※ 03 September 2019 paper accepted ※ 05 December 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEZBA3 | No Beam-Loss Quadrupole Scan for Transverse Phase Space Measurements | 650 |
|
||
Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University. Facility for Rare Isotope Beams (FRIB) at Michigan State University is based on a high power heavy ion linac and beam commissioning is under way. For evaluation of beam Twiss parameters and rms emittance, we routinely use multiple profile measurements while the strength of an upstream quadrupole is varied. The change of the quadrupole strength results in a beam mismatch downstream of the profile monitor which can cause beam losses. This is not acceptable in a high energy beamline. To avoid this transverse mismatch, we developed a beam matching procedure by optimization of quadrupoles’ setting downstream of the profile monitor. Using this procedure we were able to eliminate beam losses during the quadrupole scan, and evaluate beam Twiss parameters and rms emittance. Examples of using this procedure in the folding segment of the FRIB linac will be reported. |
||
![]() |
Slides WEZBA3 [7.964 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEZBA3 | |
About • | paper received ※ 27 August 2019 paper accepted ※ 05 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLM03 | The LLRF Control Design and Validation at FRIB | 667 |
|
||
Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661. One of the challenges in designing the low level radio frequency (LLRF) controllers for the Facility for Rare Isotope Beams (FRIB) is the various types of cavities, which include 5 different frequencies ranging from 40.25 MHz up to 322 MHz, and 4 different types of tuners. In this paper, the design strategy taken to achieve flexibility and low cost and the choices made to accommodate the varieties will be discussed. The approach also allowed easy adaptation to major design changes such as replac-ing two cryo-modules with two newly designed room temperature bunchers and the addition of high-voltage bias to suppress multi-pacting in half wave resonators (HWRs). With the successful completion of the third accelerator readiness review (ARR03) commissioning in early 2019, most of the design has been validated in the real accelerator system, leaving only HWRs which are constantly undergoing tests in cryo-module bunker. The integrated spark detector design for HWRs will also be tested in the near future. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLM03 | |
About • | paper received ※ 31 August 2019 paper accepted ※ 05 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLM62 | First Cold Test Results of a Medium-Beta 644 MHz Superconducting 5-Cell Elliptical Cavity for the FRIB Energy Upgrade | 731 |
SUPLS07 | use link to see paper's listing under its alternate paper code | |
|
||
Funding: Work supported by Michigan State University. The superconducting linac for the Facility for Rare Isotope Beams (FRIB) will accelerate ions to 200 MeV per nucleon, with the possibility of a future energy upgrade to 400 MeV per nucleon via additional cavities. A 5-cell superconducting β = 0.65 elliptical cavity was designed for this purpose. Two unjacketed 5-cell niobium cavities were fabricated; the first of these was Dewar tested in February 2019. The surface preparation was bulk electropolishing (EP, 150 µm), hydrogen degassing (600°C, 10 hours), light EP (20 µm), clean-room high-pressure water rinsing, and in-situ baking (120°C, 48 hours). We achieved Q0 = 2·1010, equivalent to Rs = 10 nΩ, at the design gradient of 17.5 MV/m. The cavity was tested in a newly refurbished FRIB test Dewar, equipped with a variable input coupler. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLM62 | |
About • | paper received ※ 02 September 2019 paper accepted ※ 19 November 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLH01 | Longitudinal Beam Profile Measurement by Silicon Detector in Facility for Rare Isotope Beams at Michigan State University | 799 |
|
||
Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University The Facility for Rare Isotope Beams (FRIB) includes a continuous wave superconducting linear accelerator designed to deliver 400 kW ion beams with energies above 200 MeV/u. The beam commissioning of the first three cryomodules took place in the summer of 2018. A temporary diagnostic station installed after the first three cryomodules included a Silicon Detector (SiD) to measure absolute energy and bunch shape of 40Ar and 86Kr beams accelerated up to 2.3 MeV/u. The beam longitudinal emittance was evaluated by measuring bunch shapes while the bunching field amplitude of the upstream resonator was varied. In this paper, we will present the SiD setup and measurement results. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLH01 | |
About • | paper received ※ 28 August 2019 paper accepted ※ 31 August 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLH03 | Redesign of ReA3 4-Rod RFQ | 807 |
|
||
Funding: Work supported by the U.S. DoE Office of Science under Cooperative Agreement DE-SC0000661 and the NSF under Cooperative Agreement PHY-1102511, the State of Michigan and Michigan State University. The present RFQ of ReA3 reaccelerator at Michigan State University (MSU) has been commissioned in 2010. This 4-rod RFQ was designed to accelerate the prebunched 80.5 MHz beams with the lowest Q/A = 1/5. However, the lack of proper cooling limited the RFQ performance to the pulsed operation with the lowest Q/A = 1/4. The design voltage for Q/A = 1/5 has never been reached even in a pulsed mode due to the sparking. In 2016 we initiated the upgrade of ReA3 RFQ to support high duty cycle (up to CW) operation with Q/A = 1/5 beams. The upgrade included the new rods with trapezoidal modulation, and new stems with improved cooling. The redesigned 80.5 MHz RFQ will consume only 65% rf power of the present RFQ for Q/A = 1/5 beam. It will provide the transmission up to 78% for 16.1 MHz beams and 89% for 80.5 MHz beams. High reliability and efficiency of the RFQ are very important for the going-on reaccelerator upgrade to ReA6 and for future operation as a part of FRIB. The electrodes have been manufactured and are being installed. The RF and beam tests are scheduled to summer 2019. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLH03 | |
About • | paper received ※ 27 August 2019 paper accepted ※ 01 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLH04 | Beam Envelope Reconstruction for FRIB-FS1 Transport Line Using Beam Position Monitors | 810 |
|
||
Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University. The Facility for Rare Isotope Beam (FRIB) includes a heavy ion superconducting (SC) linac. Recently we completed beam commissioning of the Linac Segment 1 (LS1) and 45° bend section of the Folding Segment 1 (FS1). Four ion species, 40Ar9+, 20Ne6+, 86Kr17+ and 129Xe26+ were successfully accelerated to a beam energy of 20.3 MeV/u. We explored the possibility of non-invasive beam diagnostics for online beam envelope monitoring based on beam quadrupole moments derived from Beam Position Monitors (BPMs)*. In future operations, various ion beam species will be accelerated and minimization of beam tuning time is critical. To address this requirement, it is beneficial to use BPMs to obtain beam Twiss parameters instead of wire scanners. This paper reports the results of BPM-based beam Twiss parameters evolution in the FS1. * R. E. Shafer, "Laser Diagnostic for High Current H beams", Proc. 1998 Beam Instrumentation Workshop (Stanford). A.I.P. Conf. Proceedings, (451), 191. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLH04 | |
About • | paper received ※ 27 August 2019 paper accepted ※ 16 November 2020 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLH06 | Commissioning Status of the FRIB Front End | 813 |
|
||
Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661. The FRIB Front End was successfully commissioned in 2017 with commissioning goals achieved and Key Per-formance Parameters (KPP) demonstrated for both 40Ar9+ and 86Kr17+ beams. Two more ion species, 20Ne6+ and 129Xe26+, have been commissioned on the Front End and delivered to the superconducting linac during the beam commissioning of Linac Segment 1 (LS1) in March 2019. In August 2019, Radio Frequency Quadrupole (RFQ) conditioning reached the full design power of 100 kW continuous wave (CW) that is required to accelerate Ura-nium beams. Start-up/shutdown procedures and opera-tional screens were developed for the Front End subsys-tems for trained operators, and auto-start and RF fast re-covery functions have been implemented for the Front End RFQ and bunchers. In this paper, we will present the current commissioning status of the Front End, and per-formance of the main technical systems, such as the ECR ion source and RFQ. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLH06 | |
About • | paper received ※ 01 September 2019 paper accepted ※ 05 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLH07 | Commissioning of the FRIB/NSCL New ReA3 4-Rod Radio Frequency Quadrupole Accelerator | 817 |
|
||
Funding: This work was supported by the National Science Foundation under Grant PHY-15-65546 The reaccelerator facility ReA3 at the National Superconducting Cyclotron Laboratory is a state-of-the-art accelerator for ions of rare and stable isotopes. The first stage of acceleration is provided by a 4-rod radio-frequency quadrupole (RFQ) at 80.5 MHz, which accelerates ions from 12 keV/u to 530 keV/u. The internal copper acceleration structure of the RFQ was re-designed. The goal was to improve transmission while allowing to operate the RFQ in CW and accelerating ions with A/Q from 2 to 5. In this paper, we summarize the steps involved in the disassembly of the existing structure, preparation work on the retrofitted vacuum vessel, installation of the new components, acceptance testing, and commissioning of the completed RFQ. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLH07 | |
About • | paper received ※ 29 August 2019 paper accepted ※ 19 November 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WEPLH09 | FRIB Driver Linac Integration to be ready for Phased Beam Commissioning | 823 |
|
||
Funding: Work supported by the U.S. Department of Energy (DOE) Office of Science under Cooperative Agreement DE-SC0000661 The driver linac for Facility for Rare Isotope Beams (FRIB) will accelerate all stable ion beams from proton to uranium beyond 200 MeV/u with beam powers up to 400 kW. The linac now consists of 104 superconducting quarter-wave resonators (QWR), which is the world largest number of low-beta SRF cavities operating at an accelerator facility. The first 3 QWR cryomodules (CM) (β = 0.041) were successfully integrated with cryogenics and other support systems for the 2nd Accelerator Readiness Review (ARR). The 3rd ARR scope that includes 11 QWR CM (β=0.085) and 1 QWR matching CM (β=0.085) was commissioned on schedule by January 2019, and then we met the Key Performance Parameters (KPP), accelerating Ar and Kr > 16 MeV/u at this stage, in a week upon the ARR authorization. We examine a variety of key factors to the successful commissioning, such as component testing prior to system integration, assessment steps of system/device readiness, and phased commissioning. This paper also reports on the integration process of the β=0.085 CMs including the test results, and the current progress on β=0.29 and 0.53 CMs in preparation for the upcoming 4th ARR. |
||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-WEPLH09 | |
About • | paper received ※ 02 September 2019 paper accepted ※ 03 September 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
THZBA3 | Status of Beam Commissioning in FRIB Driver Linac | 951 |
|
||
Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University. The beam commissioning of linac segment 1 (LS1) composed of fifteen cryomodules consisting of total 104 superconducting (SC) resonators and 36 SC solenoids was successfully completed. Four ion beam species, Ne, Ar, Kr and Xe were successfully accelerated up to 20.3 MeV/u. The FRIB driver linac in its current configuration became the highest energy continuous wave hadron linac. We will report a detailed study of beam dynamics in the LS1 prior to and after stripping with a carbon foil. |
||
![]() |
Slides THZBA3 [11.377 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-THZBA3 | |
About • | paper received ※ 04 September 2019 paper accepted ※ 20 November 2019 issue date ※ 08 October 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |