Design of high temperature equilibrium magnetic field probes in an axisymmetric mirror machine.

Realta Fusion has developed a sophisticated digital twin model used to reconstruct mirror plasmas seen on the Wisconsin High temperature superconductor Axisymmetric Mirror (WHAM). Data from the experiment is used to differentiate between thermal and sloshing ion populations. The addition of a titanium gettering system on WHAM necessitate new thermally resistant B-Dot probe designs that maintain a signal response at low frequencies. A novel Archimedean spiral probe design was explored and tested, aiming to eliminate the risk of wire coatings sublimating, shorting probes and introducing impurities into the plasma. The new probe is designed to sustain temperatures greater than 350 C by using ceramic and bare metal components. The probe's thermal properties, quality factors, as well as its initial calibration are presented.