Xiaohao Yin

Neutrons leave no trace in ordinary glass: they pass right through, like light through a window pane. But some materials flash a faint burst of light when a particle hits them. That's how a scintillator works: a substance that turns invisible radiation into visible light. The new transparent glass SG101 is one such material.

A huge pool of clear liquid is hidden deep underground. Inside, there is nothing but a pristine 'broth' that flashes with faint light when an invisible particle flies through. This is the JUNO detector—20,000 tons of liquid scintillator built to hunt for neutrinos. The main enemy of such a hunt is not darkness but its own noise.