The Scientific Justification for a U.S. Domestic High-Performance Reactor-Based Research Facility REPORT OF THE BASIC ENERGY SCIENCES ADVISORY COMMITTEE DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. 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The report is available on-line at: https://science.energy.gov/bes/community-resources/reports/ DOI: 10.2172/1647598 The Scientific Justification for a U.S. Domestic High-Performance Reactor-Based Research Facility REPORT OF THE BASIC ENERGY SCIENCES ADVISORY COMMITTEE U.S. Department of Energy/Office of Science/July 2020 Prepared by the BESAC Subcommittee to Assess the Scientific Justification for a U.S. Domestic High-Performance Reactor-Based Research Facility ii iii Subcommittee Membership List Robert Birgeneau, University of California, Berkeley; Subcommittee Chair Sue Clark, BESAC/PNNL Pengcheng Dai, Rice University Thomas Epps, BESAC/University of Delaware Karsten Heeger, Yale University David Hoogerheide, NIST Marc Kastner, MIT, retired; BESAC Chair Bernhard Keimer, MPI-Stuttgart Despina Louca, BESAC/University of Virginia Pete Lyons, NEAC member Allan MacDonald, BESAC/University of Texas, Austin Sean O’Kelly, Idaho National Lab Brad Olsen, MIT Julia Phillips, SNL, retired David Robertson, Director, MURR reactor @ Missouri; Subcommittee Vice-Chair Anthony Rollett, BESAC/Carnegie Mellon Kate Ross, Colorado State University Mike Rowe, NIST, retired John Stevens, ANL Brian Wirth, FESAC/University of Tennessee, Knoxville Editor/writer: Al Hammond Design/Production: Maggie Powell BES Staff: Harriet Kung, Tom Russell, Katie Runkles iv Table of Contents Executive Summary. 1 Recommendations .........................................................................5 Introduction ..............................................................................6 THE SCIENTIFIC CASE 1. Neutron Scattering ......................................................................9 1a. Solid State Physics Including Quantum Materials .........................................9 1b. Soft Matter .........................................................................19 1c. Biology ............................................................................22 1d. Polarized Neutrons .................................................................25 1e. Synchrotron X-rays vs. Neutrons ......................................................27 2. Industrial Applications of Neutron Scattering ..............................................30 2a. Industrial Applications ..............................................................30 2b. Industry-Related Consortia for Use of Neutrons ........................................31 2c. Neutron Techniques with Potential Industrial Applications ...............................32 2d. Barriers to Broad Industry Use of Neutrons ............................................32 2e. Summary ..........................................................................33 3. Fundamental Physics at Reactors and Spallation Sources .....................................34 4. Isotope Production .....................................................................41 4a. Isotope Production at HFIR. 41 4b. Heavy Element Chemistry. .43 5. Materials Irradiation ....................................................................46 5a. Materials Irradiation — General. 46 5b. Fusion Materials Irradiation ..........................................................48 HEU-LEU CONVERSION Preservation of Reactor Capability with Low Enriched Uranium Fuel ..........................52 Selection of U3Si2 for HFIR Application, and the Path to Conversion. 53 Progress on High Flux Reactor Conversion since 2016 NAS and 2018 APS Studies ...............54 v MAJOR U.S. NEUTRON FACILITIES: STATUS AND FUTURE PLANS High Flux Isotope Reactor (HFIR) ........................................................57 NIST Center for Neutron Research (NCNR) ...............................................60 SNS Present and Future .................................................................63 INTERNATIONAL NEUTRON FACILITIES Institut Laue-Langevin (ILL) .............................................................66 Forschungsreaktor München II (FRM-II) ..................................................68 Jules Horowitz Research Reactor (JHR) ....................................................70 Belgian Reactor 2 (BR2) .................................................................71 Conclusions .............................................................................72 References and Notes .....................................................................77 APPENDICES 1. Oak Ridge Proposed Strategy for HFIR ...................................................83 2. The Global Effort to Convert Research Reactors to Low Enriched Uranium Fuels ...............94 3. HFIR, SNS, and NIST User Data ........................................................102 About the cover image: HFIR Refueling: July 2015 The High Flux Isotope Reactor at Oak Ridge National Laboratory is the highest flux reactor-based source of neutrons for research in the United States, and it provides one of the highest steady-state neutron fluxes of any research reactor in the world. Operating at 85 MW, an average fuel cycle for the HFIR generally runs for approximately 26 days—depending on the experiment loading for that cycle—followed by a refueling and maintenance outage for various scheduled calibrations, modifications, repairs, and inspections. The reactor underwent routine refueling in July 2015, as seen in these photos. While submersed, the spent fuel emits a luminescent blue glow due to Cherenkov radiation, in which shedding electrons move through the water faster than the speed of light in water. Once removed from the reactor, spent fuel is then relocated into an adjacent holding pool for interim storage. This image shows the removal of a HFIR fuel element from the reactor vessel during defueling operations. Image credit: Jason Richards/ORNL vi Executive Summary Why neutrons are important. Neutrons are a research embrittlement of the steel, so that the pressure tool that scientists and industrial researchers use to vessel will have to be replaced (or the reactor shut probe the properties of materials. As their name sug- down) within two to three decades. gests, they are neutral (carry no electric charge) and • In the short term, the U.S. and other nations are hence do not interact with the electric fields of atoms. committed by treaty to stop using highly-enriched Beams of neutrons can thus penetrate deeply into a uranium (HEU) fuel for research reactors—inclu- material without damaging it, and they “scatter” or ding the HFIR—as an international security bounce off the atoms within a material in ways that can measure against nuclear weapons proliferation. reveal its structure and dynamics. Neutrons are also Conversion to low-enriched uranium (LEU) will uniquely suited to exploring the magnetic properties of involve significant changes to the HFIR and, this materials. Indeed, whenever an important new material report argues, should be combined with replace- is discovered, its basic structural and magnetic proper- ment of the pressure vessel. ties will invariably be explored using neutron scattering techniques. In addition, neutron bombardment creates • Thirdly, demand by both academic and industrial the radioactive isotopes used for medical treatments of researchers for access to the HFIR and other major cancers and other diseases as well as in a wide range of U.S. neutron sources (SNS and NCNR) is already as critical industrial and national security activities. much as three times higher than current facilities can accommodate, meaning that critical research is Where they come from. Neutrons are generated within either not done or delayed for long lengths of time. a nuclear reactor, such as the High Flux Isotope Reactor In addition, national security demand for certain (HFIR) at Oak Ridge National Laboratory and the reac- radioactive isotopes produced by the HFIR is more tor at the NIST Center for Neutron Research (NCNR) than the reactor can currently supply. During a at the National Institute of Standards and Technology, shutdown of the HFIR to replace the pressure ves- by the process of nuclear fission. Neutrons can also be sel and convert to LEU fuel, it would be possible generated by colliding a beam of high-energy protons to add more beamlines that extract neutrons from with a metallic target to shake loose a pulse of neu- the reactor and more experiment stations along trons, such as at the Spallation Neutron Source (SNS) those beamlines together with enhancement of the at Oak Ridge National Laboratory. For some types of instrumentation, plus more isotope production