Facility for Rare Isotope Beams (FRIB)

Facility for Rare Isotope Beams (FRIB)

FRIB, a nuclear structure and nuclear astrophysics accelerator, enables scientists to make discoveries about the properties of rare isotopes, nuclear astrophysics, fundamental interactions, and applications for society.

East Lansing, Michigan Location
2022 Start of Operations
600 (FY 2022) Number of Users


The Facility for Rare Isotope Beams (FRIB), at Michigan State University, is a superconducting linear accelerator which can accelerate nuclei from elements across the periodic table, up to those as heavy as uranium, to 200 MeV per nucleon or over half the speed of light.  The beam from the accelerator hits a target where the nuclei shatter, producing exotic, short-lived isotopes.  Isotopes of interest are selected by an array of large magnets and directed to experimental halls to study their structure.   FRIB is the most powerful accelerator in the world for exploring the most exotic nuclei, many of which have never been observed.


The Big Bang produced only the lightest elements in our Universe. All other elements were formed within stars or through violent events such as supernovas and neutron star mergers as the cosmos evolved. The nuclear reactions involved in producing the elements are believed to involve very rare versions of the elements that have yet to be observed. These are isotopes of the elements, which have a specific number of protons per nucleus but can have a range in the number of neutrons. The science goals at FRIB are to understand how neutrons and protons combine to form isotopes, how the structure of isotopes changes as the number of neutrons gets unusually large, and the processes that populate the table of the elements. Over the last century ~2000 isotopes have been studied worldwide, using methods and equipment that scale with technology. FRIB will increase the number of isotopes available for study to ~5000.