Mixing of multiple hydrogen plasma beams in a strong magnetic field by E x B drift-induced rotation

Mixing of up to three ∼1 cm diameter plasma beams of pure hydrogen as well as mixtures of hydrogen and argon in magnetic fields of <1.6 T are studied. An external ring electrode is used to create a radial electric field that induces E x B rotation of the individual beams around a common axis. Rotation profiles with maximum speeds up to 10 km s-1 are measured from the hydrogen atomic line shapes and confirm rotation around the ring axis. Mixing to a total beam diameter of ∼2.5-3 cm is observed in density profiles measured with Thomson scattering near a target at 0.5 m downstream. Currents of up to 60 A were received by the ring, involving an addition power input of up to 5.4 kW to the plasma.