Long sustainment of FRC-equilibrium by use of center solenoid in TS-4

This paper addresses a basic equilibrium/confinement question whether a Field Reversed Configuration (FRC) with balanced amount of magnetic and thermal energies, is sustained solely by inductive magnetic flux (magnetic energy) injection of center solenoid (CS). A new finding is that the preferential injection of magnetic energy causes significant increase in resistivity of the FRC. The magnetic energy injected by Center Solenoid Current Drive (CSCD) was converted into its thermal energy through the large anomalous resistivity to maintain the FRC-equilibrium. A quasi-steady state of the high-beta (volume averaged beta ∼0.6-0.7) FRC for 0.15 ms (∼ energy confinement time of conventional FRCs) was achieved through the use of the present low power CSCD. This successful result leads us to the next stage steady sustainment experiment of an FRC by increased capacitor bank energy. (author)