Conceptual design of the ALIANCE-T mirror experiment

Abstract

The paper describes the conceptual design of a small-scale experiment within the fusion neutron source project ALIANCE (Axisymmetric LInear Advanced Neutron sourCE). The experimental machine is an axially symmetric magnetic plasma trap with a high mirror ratio, which focuses on the physical and engineering problems of mirror-based gasdynamic neutron sources. The specific research topics covered include the magnetohydrodynamic (MHD) stability of plasmas with high mirror ratios, the operation of the electrodes used for plasma stabilization, and problems related to particle and energy transport. ALIANCE-T features superconducting mirror solenoids that enable it to reach mirror ratios of ∼100 and a helicon plasma source with a power of up to 25 kW installed directly in the confinement zone between the mirrors. The expected plasma parameters are estimated using a simple analytical model, which takes into account gasdynamic axial plasma losses, cross-field transport, and the interaction of the plasma with neutral gas. It is projected that the machine will simultaneously achieve a plasma density >1013 cm−3 and a temperature >10 eV in a continuous discharge lasting for 1–8 h. This paper gives a detailed description of the key machine subsystems and introduces the analytical model used for calculation of the plasma parameters.