Researchers image lead blocks through concrete with laser-generated muons

Physicists at Romania's Extreme Light Infrastructure Nuclear Physics facility used laser-generated muons to image lead blocks through a two-meter concrete wall, New Atlas reports. The results appear in a preprint and demonstrate an artificial source of particles that penetrate dense material. The facility's 10 petawatt laser accelerated electrons into a lead barrier. Researchers then used polyethylene sheets wrapped around paraffin blocks to filter other particles from the beam. Detectors in a van beyond the concrete captured the lead blocks' shadow. The images were grainy and lacked detail; the researchers' claim to the first laser-produced muograph is also contested by uncertainty over the particles used in an earlier experiment.