trains

Toy train used to calibrate fusion reactor

Toy train used to calibrate fusion reactor

While Princeton University’s National Spherical Torus Experiment was shut down for improvements over the winter break, scientists and engineers availed themselves of the opportunity to recalibrate the reactor’s neutron sensors. To do so, they assembled a circular toy train track around the torus and ran a toy locomotive carrying a chunk of neutron-emitting californium-247 along it for three days. The New York Times explains: