Beam filamentation instability drives deuterium-tritium fusion with polarized neutron emission
Abstract
Filamentation instabilities are generally regarded as detrimental to fast-electron transport in fusion plasmas because they increase beam divergence and redistribute deposited energy. Here, we use two-dimensional particle-in-cell simulations coupled to a spin-dependent deuterium-tritium fusion module to investigate whether filamentation can instead transfer energy from counterstreaming electrons to prepolarized fusion ions. The simulations show that magnetic filaments, together with longitudinal inductive and transverse charge-separation electric fields, accelerate initially stationary deuterons and tritons to energies at which fusion reactions occur. Over the parameter range examined, the calculated neutron yield increases with the saturated magnetic-field energy. The model further predicts anisotropic, spin-resolved neutron emission. The direction of maximum neutron polarization is approximately perpendicular to the dominant deuterium-tritium collision direction and evolves with the angular distribution of the reacting ions. These results suggest that beam filamentation can couple relativistic-electron energy to fusion ions and that polarized neutron emission may provide a reaction-weighted signature of the underlying plasma dynamics.
Related
- Axion Emission Controlled by Ion Motion in Relativistic Beam-Plasma Filamentation
- Programmable Intrinsic Circularly Polarized Emission
- Probing Neutrinophilic Axion-Like Particles in Tritium Beta Decay
- Integrated assessment of tritium releases from fission and fusion energy systems and their environmental implications
- Observation of Replica Symmetry Breaking in Filamentation and Multifilamentation
BibTeX
@misc{qiu2026beam,
title = {{Beam filamentation instability drives deuterium-tritium fusion with polarized neutron emission}},
author = {Guanqi Qiu and Deji Liu and Dongchi Cai and Ronghao Hu and Zheng Gong and Xueqing Yan},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.11061},
eprint = {2610.11061},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.11061},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Beam filamentation instability drives deuterium-tritium fusion with polarized neutron emission
AU - Guanqi Qiu
AU - Deji Liu
AU - Dongchi Cai
AU - Ronghao Hu
AU - Zheng Gong
AU - Xueqing Yan
PY - 2026
DA - 2026/10/08
PB - arXiv
DO - 10.48550/arxiv.2610.11061
UR - https://arxiv.org/abs/2610.11061
AB - Filamentation instabilities are generally regarded as detrimental to fast-electron transport in fusion plasmas because they increase beam divergence and redistribute deposited energy. Here, we use two-dimensional particle-in-cell simulations coupled to a spin-dependent deuterium-tritium fusion module to investigate whether filamentation can instead transfer energy from counterstreaming electrons to prepolarized fusion ions. The simulations show that magnetic filaments, together with longitudinal inductive and transverse charge-separation electric fields, accelerate initially stationary deuterons and tritons to energies at which fusion reactions occur. Over the parameter range examined, the calculated neutron yield increases with the saturated magnetic-field energy. The model further predicts anisotropic, spin-resolved neutron emission. The direction of maximum neutron polarization is approximately perpendicular to the dominant deuterium-tritium collision direction and evolves with the angular distribution of the reacting ions. These results suggest that beam filamentation can couple relativistic-electron energy to fusion ions and that polarized neutron emission may provide a reaction-weighted signature of the underlying plasma dynamics.
ER -