Reviewed by Frances BriggsSep 22 2025
ORNL has built a mobile muon detector projected to improve spent nuclear fuel monitoring and tackle a critical challenge for quantum computing.
Image Credit: Motion Loop/Shutterstock.com
Muons, similar to neutrons, are subatomic particles that travel at almost the speed of light and can penetrate deep into matter. They allow scientists to comprehend the atomic scale without destroying samples. However, muons exist only for a few fleeting microseconds. This whisper of existence has made it difficult for scientists to make use of them for material analysis.
However, the new detector has found a way to capitalize on microsecond matter, taking a significant step toward maintaining nuclear material safety and accountability. It also supports the development of advanced nuclear reactors to assist in solving waste management concerns. Additionally, it could be used to develop algorithms and strategies to handle mistakes produced by cosmic radiation in qubits, the fundamental units of information in quantum computing.
This project exemplifies the power and innovation of interdisciplinary collaboration at ORNL. We are thrilled to have brought this vision to life. We have a fantastic community here at ORNL, and the support I’ve received has been invaluable.
JungHyun Bae, Wigner Distinguished Staff Fellow, Oak Ridge National Laboratory
The muon detector, which is based on Spallation Neutron Source neutron detector technology and employs wavelength-shifting fibers, could help scientists better comprehend large-scale, dense materials such as protected special nuclear materials and spent nuclear fuel.
The detector was developed over more than two years by the lab’s Neutron Sciences and Fusion and Fission Energy and Sciences directorates. It is expected to enable a wide range of applications, including nuclear fuel research. This year, the muon detector will be moved to a new building on the ORNL campus for practical measurements.
Collaborative work is essential in scientific research. At ORNL, we have a wealth of expertise, and the willingness to work together is what made this project a success.
Polad Shikhaliev, Senior Detector Scientist, Oak Ridge National Laboratory
The novel detector’s capacity to record muon energy and scattering angles simultaneously sets it apart from previous muon tomography devices, which normally depend on single readings. This method gives an additional view of a sample, such as a canister with damaged or hazardous materials.
Similarly, the detector’s properties will help scientists understand how cosmic radiation interacts with qubits. Due to their intrinsic fragility, qubits rapidly lose their quantum state. Without overcoming this constraint, scaling up and implementing usable quantum computers outside laboratory settings would remain challenging.
By capturing how muons scatter and deposit energy in different materials, the detector will provide data that informs the design of more robust quantum hardware and improves error correction algorithms, two major barriers in scaling quantum tech.
The project began with an idea established by Bae during his doctoral study, which centered on complicated computational simulations to test muon tomography applications. Visiting the American Museum of Science and Energy in Oak Ridge, Tennessee, Bae discovered an integral design in a neutron detector on exhibit, created by the Neutron Sciences Directorate's Detectors Group at ORNL, directed by Yacouba Diawara.
That detector made the 2012 R&D 100 list. Diawara also published Neutron Detectors for Scattering Applications, a reference for specialists and young students on the most popular neutron detectors used in neutron scattering facilities. Bae approached Diawara, and together they constructed the muon tomography system.
This collaboration is a testament to what can be accomplished when scientists and engineers at ORNL come together with a shared vision. The design for the muon detector originated from a neutron detector built specifically for the Spallation Neutron Source more than ten years ago. The return on investment for that original detector has well exceeded our expectations, generating leading edge technology for discovery science adjacent to and complementary of the power of neutrons.
Yacouba Diawara, Distinguished R&D Staff Member and Group Leader, Oak Ridge National Laboratory
Neutron Detector Mobilizes Muons for Nuclear, Quantum Material
In a muon tomography detector, cosmic-ray muons interact with an object and strike scintillators that emit photons. Wavelength-shifting fibers transmit the photons to photodetectors that digitize the signals, which researchers analyze to reconstruct high-resolution images. Video Credit: Phoenix Pleasant/ORNL, U.S. Dept. of Energy