TY  - JOUR
AU  - Heidbrink, W. W.
AU  - Baylor, L. R.
AU  - Büscher, Markus
AU  - Engels, Ralf W.
AU  - Garcia, A. V.
AU  - Ghiozzi, A. G.
AU  - Miller, G. W.
AU  - Sandorfi, A. M.
AU  - Wei, X.
AU  - Zheng, X.
TI  - A research program to measure the lifetime of spin polarized fuel
JO  - Frontiers in physics
VL  - 12
SN  - 2296-424X
CY  - Lausanne
PB  - Frontiers Media
M1  - FZJ-2024-03546
SP  - 1355212
PY  - 2024
AB  - The use of spin polarized fuel could increase the deuterium-tritium (D-T) fusion cross section by a factor of 1.5 and, owing to alpha heating, increase the fusion power by an even larger factor. Issues associated with the use of polarized fuel in a reactor are identified. Theoretically, nuclei remain polarized in a hot fusion plasma. The similarity between the Lorentz force law and the Bloch equations suggests polarization can be preserved despite the rich electromagnetic spectrum present in a magnetic fusion device. The most important depolarization mechanisms can be tested in existing devices. The use of polarized deuterium and $^3$He in an experiment avoids the complexities of handling tritium, while encompassing the same nuclear reaction spin-physics, making it a useful proxy to study issues associated with full D-T implementation. $^3$He fuel with 65% polarization can be prepared by permeating optically-pumped $^3$He into a shell pellet. Dynamically polarized 7Li-D pellets can achieve 70% vector polarization for the deuterium. Cryogenically-frozen pellets can be injected into fusion facilities by special injectors that minimize depolarizing field gradients. Alternatively, polarized nuclei could be injected as a neutral beam. Once injected, the lifetime of the polarized fuel is monitored through measurements of escaping charged fusion products. Multiple experimental scenarios to measure the polarization lifetime in the DIII-D tokamak and other magnetic-confinement facilities are discussed, followed by outstanding issues that warrant further study.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001248687500001
DO  - DOI:10.3389/fphy.2024.1355212
UR  - https://juser.fz-juelich.de/record/1026967
ER  -