On 3 August fusion specialists SHINE Technologies announced that it has demonstrated clearly visible Cherenkov radiation produced by fusion, for what is believed to be the first time in history. Historically, fusion has been demonstrated and detected with instrumentation responding to non-visible radiation.

This fusion-driven Cherenkov radiation effect results from deuterium-tritium fusion operations on SHINE’s main campus, supporting the launch of the company’s FLARE (Fusion Linear Accelerator for Radiation Effects) service, and ultimately supporting its isotope production process. The target chamber of SHINE’s fusion system is submerged underwater, allowing for the generation of visible Cherenkov radiation.

This visible evidence provides further proof that fusion can produce neutrons on a par with some nuclear fission reactors. “The Cherenkov radiation effect produced here was bright enough to be visible, which means there’s a lot of fusion happening, about 50 trillion fusions per second. At a billion fusions per second, you might have measurable Cherenkov radiation but not visible amounts,” said Gerald Kulcinski, Grainger professor of Nuclear Engineering-Emeritus and director of Fusion Technology-Emeritus at the University of Wisconsin-Madison.

Cherenkov radiation is produced when charged particles moving at light speed enter a medium such as water that slows them down, meaning that for a short while they are travelling at a speed greater than the theoretical limit in that medium. Light travels at about 75% of its speed in a vacuum when in water, and particles moving faster than this form a shock wave as they slow down, releasing energy that creates the blue glow. In the case of fusion, the fast charged particles are believed to be created when hydrogen absorbs a neutron and emits a high energy gamma ray that then strikes an electron, accelerating it to near the speed of light.

SHINE is industrialising and scaling fusion technology in a four-phased approach. Its current fusion system bolsters the first phase of inspecting industrial components and will be critical in the second phase of producing medical isotopes. SHINE plans to deploy eight such fusion systems inside ‘The Chrysalis’, its fusion driven neutron production facility, as part of a project supported by the US Department of Energy’s National Nuclear Security Administration. SHINE plans to continue iterating and scaling its technology to recycle nuclear waste and generate fusion power.