A versatile end tank system called “Cusp” has been constructed to comply with the main objectives of Hanbit mirror machine - a) control of neutral reflux, b) plasma application by using the end loss plasma flow, c) providing axi-symmetric minimum-B configuration for MHD study. Cusp system consists of a vacuum vessel, a liquide-helium-cooled cryopump, a set of magnets to provide axi-symmetric semi-cusp shaped magnetic field configuration

The pumping speed of the cryopump has been designed to be 2×105 liter/sec and tested to be 2.3×105 liters/sec. To observe the effect of neutral reflux, dynamic neutral pressure and end loss ion's energy distribution has been measured at Cusp during plasma shot. It has been shown that the energy confinement at the Central Cell has been improved

For plasma application, a gas target divertor3 simulation experiment has been performed as a feasibility study. A target has been mounted at the end of Cusp system and dynamic surface temperature has been measured by IR camera. End loss ion current also has been measured. The system configuration and experimental result will be presented