The Annular Core Research Reactor (ACRR) Provides a Thermal Neutron Spectrum

At the ACRR facility, experimenters can subject various test objects to a mixed photon and neutron irradiation environment featuring either a very rapid pulse rate or a long-term, steady-state rate.

The ACRR offers several special features:


  • A large central cavity with very little radiation gradient, despite a capability for high radiation intensity
  • The ability to determine with a high degree of accuracy the actual radiation dose delivered to each test article
  • A limited capability to tailor the neutron energy spectrum and reduce or increase the photon intensity by selecting the appropriate interaction material to be positioned between the core and the test article

Research and other activities

The radiation produced at the ACRR is used for the following research activities:

  • Neutron-scattering experiments
  • Nondestructive testing, including neutron radiography
  • Neutron activation analysis and testing of materials
  • Advanced reactor fuels development and testing
  • Radioisotope production
  • Basic radiation effects science
  • Public outreach and education


Test articles, components, and systems irradiated at the ACRR include the following:

  • Electronic circuit boards and components
  • Neutron or gamma dosimetry devices, both passive (e.g., activation and fission foils) and active (e.g., neutron/gamma detectors and semiconductor devices)
  • Explosive components, including neutron generators, and radioactive materials (e.g., fission products and tritium)
  • Experiment-holding/positioning fixtures
  • Neutron-spectrum-modifying fixtures such as moderators and neutron absorbers
  • Nuclear and nuclear fuel materials (e.g., fissionable material for commercial, experimental, and space reactor fuel types)
Annular Core Research Reactor at Sandia National Laboratories

Contact us today to discuss your gamma irradiation Needs!