Researchers at the Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering in Romania have successfully captured images through a concrete wall nearly 2 meters thick. The team utilized a 10-petawatt laser, known as ELI-NP, to generate a controlled beam of muons, which are particles approximately 200 times heavier than electrons.
The experiment involved accelerating electrons to high energies by firing the laser into a gas target. Upon colliding with a solid target, the electrons produced light flashes that generated muon pairs. A specialized filter made of plastic and paraffin was then employed to isolate the muon beam from other particles before passing it through the concrete barrier.
The resulting images revealed the shadow of a stack of lead bricks located behind the 1.8-meter-thick concrete layer. While the initial images were of low resolution, the researchers stated that this is the first demonstration of imaging using an artificial, laser-driven muon beam. They plan to improve the technology by refining both the detectors and the laser system.
Muon imaging, or muography, has been studied for several years, notably identifying a hidden chamber in the Great Pyramid of Giza in 2023. Earlier in 2026, a separate international team led by Lawrence Livermore National Laboratory and Colorado State University also achieved a particle flash suitable for imaging. Future developments may lead to devices capable of scanning through dense materials.
