Using a Toy Train To Calibrate a Reactor

alfredos writes "Physicists and engineers at Princeton Plasma Physics Laboratory built tracks inside a fusion reactor and ran a toy train for three days to help them with their calibrations. From the article: 'The modified model of a diesel train engine was carrying a small chunk of californium-252, a radioactive element that spews neutrons as it falls apart. “We needed to refine the calibration technique to make sure we are measuring our neutrons as accurately as possible,” said Masa Ono, the project head of the National Spherical Torus Experiment.'"

Comments

Done something similar

[Wonko the Sane]

I did this plenty of times in the Navy, except that they have a tube installed that circled the reactor between it and the detectors.

The tube contained the source and you moved it from detector to detector by pulling on a cable that was attached to both ends.

Spherical Torus?

[tunabomber]

Those two surfaces are fundamentally different, topologically speaking. Would a spherical torus would look something like a 4-sided triangle? Or sound like one hand clapping?

Cosmic.

Re:Spherical Torus?

[mako1138]

I think it's called a "spherical" torus because the design represents an evolution from a plain torus. You squash a donut into a roughly spherical space. IIRC the advantage of this configuration over a tokamak is that the stability of the plasma is improved. However there is a fundamental trade-off between stability and energy density, so these designs are less likely to be workable sources of fusion energy.

Re:Aha!

[type40]

That how I use to sneak into the house back in high-school. I'd coast my car into the driveway and slow walk across the lawn. A five count per step was slow enough to keep the motion light (that was aimed at my light sleeping parents bedroom) from going off.