Studies of a Straight Field Line Mirror with Emphasis on Fusion-Fission Hybrids

Abstract

This is an accepted version of a paper published in Fusion science and technology. This paper has been peer-reviewed but does not include the final publisher proof-corrections or journal pagination.Citation for the published paper: Ågren, O., Moiseenko, V., Noack, K., Hagnestål, A. AbstractThe straight field line mirror (SFLM) field with magnetic expanders beyond the confinement region is proposed as a compact device for transmutation of nuclear waste and power production. A design with reactor safety and a large fission to fusion energy multiplication is analyzed. Power production is predicted with a fusion Q =0.15and an electron temperature around 500 eV. A fusion power of 10 MW may be amplified to 1.5 GW fission power in a compact hybrid mirror machine. In the SFLM proposal, quadrupolar coils provide stabilization of the interchange mode, radiofrequency heating is aimed to produce a hot sloshing ion plasma, and magnetic coils are computed with an emphasis to minimize holes in the fission blanket through which fusion neutrons could escape. Neutron calculations for the fission mantle show that nearly all fusion neutrons penetrate into the fission mantle. A scenario to increase the electron temperature with a strong ambipolar potential suggests that an electron temperature exceeding 1 keV could be reached with a modest density depletion by two orders in the expander. Such a density depletion is consistent with stabilization of the drift cyclotron loss cone mode.PACS: 28.52.Av, 28.41.Ak.3