Updates & News

• On 24 February, the U.S. Department of Energy Office of Science (DOE-SC) approved the start of execution of a $49.7 million instrument at the Facility for Rare Isotope Beams (FRIB). DOE-SC granted Critical Decision 2/3 approval to FRIB at Michigan State University (MSU) for the start of execution of the High Transmission Beam Line (HTBL), one of the two segments of the HRS. 

• The Final Design Report for the High Transmission Beam Line (HTBL) was published 24 September 2024. 

• The High Rigidity Spectrometer for FRIB was featured in the 2023 Nuclear Science Advisory Committee Long Range Plan "A New Era for Discovery". 

• Details of the ion-optical design of the HRS was published in January 2023: S. Noji et al., Nuclear Instruments and Methods in Physics Research Section A, Volume 1045, 167548 (2023). 

• The HRS was featured in Nuclear Physics News in December 2022, R.G.T. Zegers , "The High Rigidity Spectrometer at the Facility for Rare Isotope Beams", Nuclear Physics News 32, 16 (2022)

• The U.S. Department of Energy Office of Science (DOE-SC) Office of Nuclear Physics approved Critical Decision 1 (CD-1: Approve Alternative Selection and Cost Range) for the High Rigidity Spectrometer project 16 September 2020.

Overview

The High Rigidity Spectrometer (HRS) will be the centerpiece experimental tool of the Facility for Rare-Isotope Beams (FRIB) fast-beam program. The fast-beam program at FRIB has tremendous discovery potential, enabling experiments with beam intensities of few ions per second or less through the luminosity afforded by thick targets. The high magnetic rigidity of the HRS (8 Tm) will match the rigidities for which rare-isotope production yields at the FRIB fragment separator are maximum across the entire chart of nuclei and enable experiments with the most exotic, neutron-rich nuclei available at FRIB.

The figure above provides a schematic overview of the scope of the HRS at FRIB and integration example with other detector systems. The HRS consists of two subprojects: the High-Transmission Beam Line (HTBL) and the Spectrometer Section. Rare isotopes beams are transported from the FRIB fragment separator through the HTBL to the target position at the HRS. The first element of the HRS after the target station is the sweeper dipole, which diverts charged particles toward a focusing beam line that transports particles to the spectrometer dipoles and the focal plane detectors. The spectrometer dipoles provide the precise exit channel characterization with momentum and particle identification resolutions required for the broad scientific program with the HRS.

Also shown in the figure are the Gamma-Ray Energy Tracking Array (GRETA) and the Modular Neutron Array (MoNA-LISA). There are many other state-of-the-art detectors that have been developed by the User Community that will be used in combination with the HRS to achieve the scientific objectives of FRIB.

A Preliminary Design Report has been developed with input from the FRIB user community. The U.S. Department of Energy Office of Science (DOE-SC) Office of Nuclear Physics approved Critical Decision 1 (CD-1: Approve Alternative Selection and Cost Range) for the High Rigidity Spectrometer project 16 September 2020.

The Final Design Report for the High Transmission Beam Line (HTBL) was published 24 September 2024. 

On 24 February, the U.S. Department of Energy Office of Science (DOE-SC) approved the start of execution of a $49.7 million instrument at the Facility for Rare Isotope Beams (FRIB). DOE-SC granted Critical Decision 2/3 approval to FRIB at Michigan State University (MSU) for the start of execution of the High Transmission Beam Line (HTBL), one of the two segments of the HRS