Formation of collisionless high-beta plasmas by application of odd-parity rotating magnetic fields

Odd-parity rotating magnetic fields (RMF$_o$) have been applied to mirror-configuration plasmas in a device of 4-cm radius, defined by discrete co-axial copper-ring flux conservers, and with divertor chambers beyond both mirrors. At an applied RF power of 10 kW and a bias field of 50 G, line-averaged electron density of 1e12 cm$^{-3}$ and excluded flux of 0.005 mVs have been sustained for over 0.5 ms, corresponding to a Coulomb collisionality of $<$ 0.02. The divertors allow reduction of the electron-neutral collision frequency to similarly low levels. Under such conditions, measurements of RMF$_o$ coupling indicate full penetration of the RMF$_o$ to the major axis.