Diagnostics & Measurement
Thomson Scattering
Firing a laser through the plasma and reading the scattered light to measure temperature and density.
Thomson scattering shines a laser through the plasma; electrons scatter the light, and the Doppler broadening of the scattered spectrum gives the electron temperature while its intensity gives the density. It is the gold-standard local measurement of both.
Common questions
What does Thomson scattering measure?
Laser light scattered off plasma electrons gives local electron temperature and density profiles — a cornerstone diagnostic for confirming the plasma's core conditions.
Why is it valuable?
Because it directly measures the temperature and density that set fusion power, turning modelled profiles into measured ones.