What is it about?

This publication looked at the operation of superconducting fusion magnets under the bombardment of high energy particles. More specifically, we measured the critical current while actively irradiating REBCO tapes at 20 K. We find that the effect of ballistic displacement effects is likely unimportant and that the reduction of critical current observed in laboratory experiments is predominantly due to localized ion beam heating.

Featured Image

Why is it important?

Prior to this publication, it was unclear if the steady state operation of fusion magnets would be affected by neutron bombardment. This was potentially a big problem for fusion power plants which would have required significantly more shielding to operate (i.e., larger size and cost). A prior publication made the opposite case but did not have means to discriminate between ballistic displacements and beam heating. This publication retires this concern. In addition, it offers a new means to account for beam heating in ion irradiations, which is valuable to cryogenic irradiation experiments in general.

Perspectives

I had a lot of fun working on this project because it started with the sudden realization (during one of my regular 4am runs around the Boston Charles river with my PhD advisor) that nobody had ever tested if the loss free transport of current in superconductors would be perturbed during irradiation (which seemed like such an obvious problem!). About a year and dozens of accelerator-hours, the story of the "beam on effect" culminated with a showdown at a small topical meeting in Italy between two competing groups at MIT and Oxford (different perspective, different setups) where we eventually agreed on the meaning of our measurement.

Alexis Rustam Devitre
Massachusetts Institute of Technology

Read the Original

This page is a summary of: Beam heating explains critical current suppression measured during ion irradiation of REBCO tapes, Superconductor Science and Technology, November 2024, Institute of Physics Publishing,
DOI: 10.1088/1361-6668/ad95c2.
You can read the full text:

Read

Contributors

The following have contributed to this page