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The Facility for Rare Isotope Beams (FRIB) is an ac-celerator-based facility funded by the US Department of Energy for nuclear physics research. FRIB is nearing the end of technical construction, with first user beams ex-pected in Summer 2022. Key features are the delivery of a variety of rare isotopes with a beam energy of ’ 200 MeV/u and a beam power of up to 400 kW. The facility is upgradable to 400 MeV/u and multi-user capability. The FRIB driver linac consists of 324 superconducting resonators and 69 superconducting solenoids in 46 cry-omodules. FRIB is the first linac to deploy a large number of HWRs (220) and the first heavy ion linac to operate at 2 K. We report on the completion of production and in-stallation of the FRIB cryomodules and phased beam commissioning results., Proceedings of the 20th International Conference on RF Superconductivity, SRF2021, East Lansing, MI, USA

Rare isotope beams are produced at FRIB via fragmentation of a primary heavy ion beam in a thin target. The isotope beam of interest is contaminated with other fragments, which must be filtered out to ensure the delivery of rare isotopes with desired rates and purities. One of the stages of fragment separation uses an RF deflecting cavity to provide time-of-flight separation. However, to avoid neighboring bunches overlapping with each other and with the contaminants, it is necessary to increase the inter-bunch distance by a factor of four, corresponding to a 20.125 MHz rate. To solve this problem, we have developed an RF chopper system for the 500 keV/u primary heavy-ion beams. The system consists of a deflecting quarter wave resonator (QWR) cavity operating at 60.375 MHz, two dipole steering magnets, and a beam dump. In this paper, we present and discuss the optimization of the electromagnetic design of the QWR cavity and magnets, as well as some aspects, related to beam dynamics and conceptual engineering design., Proceedings of the 5th North American Particle Accelerator Conference, NAPAC2022, Albuquerque, NM, USA

The Facility for Rare Isotope Beams (FRIB) project has completed technical construction in January 2022, five months ahead of schedule baselined about 10 years ago. Beam commissioning has been planned in seven phases starting from 2017 when the normal-conducting ion source and RFQ were commissioned. In April 2021, FRIB driver linac commissioning was completed with heavy ion beams being accelerated to energies above 200 MeV/u using 324 superconducting radiofrequency (SRF) resonators contained in 46 cryomodules. In preparation for high-power operations, a liquid lithium charge strip-per was used to strip uranium beam from average charge state of 33+ to 78+, and multiple charge states were accelerated simultaneously in the linac. By January 2022, FRIB target and fragment separator commissioning was completed with rare-isotope beams produced and identified. In May 2022, the first FRIB user scientific experiment was successfully conducted. This talk summarizes the FRIB accelerator project commissioning and early operations experience with discussions on strategic planning, operational envelope conformance, technical risk mitigation, and lessons learned., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

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., Proceedings of the North American Particle Accelerator Conference, NAPAC2019, Lansing, MI, USA

High continuous wave (cw) current of highly charged ion beams are required for several heavy ion accelerator facilities including the Facility for Rare Isotope Beams (FRIB). In most cases, Electron-Cyclotron-Resonance (ECR) ion sources remain the only ion source capable to meet the beam intensity requirement for these facilities. Performances of ECR ion source have increased by several order of magnitude since their inception in the 1970s mostly driven by increasing the resonance frequency with today current state of the art ECR ion source operating from 24 to 28 GHz. This paper provides an overview of recent advance in the design and operation of ECR ion source including plans to develop the next generation of ion source capable of operating above 40 GHz. A detailed account of the design and status of the new superconducting ECR ion source in construction for FRIB will also be reported., Proceedings of the North American Particle Accelerator Conference, NAPAC2019, Lansing, MI, USA

This paper presents recent developments of accelerator physics related topics for the Facility for Rare Isotope Beams (FRIB) being built at Michigan State University. While extensive beam dynamics simulations including all known errors do not show uncontrolled beam losses in the linac, ion beam contaminants extracted from the ECR ion source together with main ion beam can produce significant losses after the charge stripper. These studies resulted in development of beam collimation system at relatively low energy of 16 MeV/u and room temperature bunchers instead of originally planned superconducting ones. Commissioning of the Front End enabled detailed beam physics studies accompanied with the simulations using several beam dynamics codes. Settings of beam optics devices from the ECR to MEBT has been developed and applied to meet important project milestones. Similar work is planned for the beam commissioning of the first 3 cryomodules in the superconducting linac., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The radio-frequency quadrupole (RFQ) at the Facility for Rare Isotope Beams (FRIB) is a 4-vane type cavity designed to accelerate heavy ion beams with charge states Q/A between 1/7 and 1/3 from 12 keV/u to 0.5 MeV/u. The RFQ was assembled in the FRIB tunnel in November 2016. Bead-pull measurements and tuning were performed with low RF power. The RFQ has been conditioned to 59 kW in August 2017, which is sufficient to accelerate the Key Performance Parameter (KPP) beams, Argon and Krypton. The RFQ has been successful-ly commissioned with KPP beams in CW regime in Octo-ber 2017. 40Ar⁹⁺ and 86Kr¹⁷⁺ beams were accelerated by the FRIB RFQ in the CW regime to the designed energy of 0.5 MeV/u. With the multi-harmonic buncher operation-al, the FRIB RFQ commissioning has been completed with bunched beam in February 2018. The beam trans-mission efficiency through the RFQ was in good agree-ment with PARMTEQ simulation results. The detailed results from the FRIB RFQ tuning, high power condition-ing and beam commissioning will be presented in this paper., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada