Physical thickness characterization of the FRIB production targets

Lee, D. J. [Michigan State University, East Lansing, MI (United States)]; Reaume, M. [Michigan State University, East Lansing, MI (United States)]; Franklin, W. [Michigan State University, East Lansing, MI (United States)]; Song, J. [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000211630564)

doi:10.1088/1748-0221/21/07/t07005

DOE OSTI · 3580376

Physical thickness characterization of the FRIB production targets

Lee, D. J. [Michigan State University, East Lansing, MI (United States)]·Reaume, M. [Michigan State University, East Lansing, MI (United States)]·Franklin, W. [Michigan State University, East Lansing, MI (United States)]·Song, J. [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000211630564)

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Abstract

The FRIB heavy-ion accelerator, commissioned in 2022, is a leading facility for producing rare isotope beams (RIBs) and exploring nuclei beyond the limits of stability. These RIBs are produced via reactions between stable primary beams and a graphite target. Approximately 20–40% of the primary beam power is deposited in the target, requiring efficient thermal dissipation. Currently, FRIB operates with a primary beam power of up to 20 kW. To enhance thermal dissipation efficiency, a single-slice rotating graphite target with a diameter of approximately 30 cm is employed. The effective target region is a 1 cm-wide outer rim of the graphite disc. To achieve high RIB production rates, the areal thickness variation must be constrained within 2%. This paper presents physical thickness characterizations of FRIB production targets with various nominal thicknesses, measured using a custom-built non-contact thickness measurement apparatus.

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Instrumentation for radioactive beams (fragmentation devices, fragment and isotope, separators incl. ISOL, isobar separators, ion and atom traps, weak-beam diagnostics, radioactive-beam ion sources)Targets (spallation source targets, radioisotope production, neutrino and muon sources)

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Lee, D. J. [Michigan State University, East Lansing, MI (United States)], Reaume, M. [Michigan State University, East Lansing, MI (United States)], Franklin, W. [Michigan State University, East Lansing, MI (United States)], Song, J. [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000211630564). 2026-07-10. Physical thickness characterization of the FRIB production targets. https://doi.org/10.1088/1748-0221/21/07/t07005

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