Intense ion beam propagation in a magnetic field

An experiment is in progress to study collective interactions between a preformed hydrogen plasma column, contained in a solenoidal magnetic field, and an axially injected intense proton beam. A preliminary investigation, without the preformed plasma, has been made to determine the propagation characteristics of the beam through the solenoidal magnetic field region which starts 63 cm from the diode. A 7.5 cm diameter, cylindrical, proton beam of 100 ns duration is extracted from a planar, racetrack type, magnetically insulated diode. The diode is operated at 600 kV, insulated at 2.4 B/sub critical/, and delivers approximately 1 kA of protons to the magnetic field region. The solenoid is 61 cm long and is constructed of 24 equally spaced turns with an 18 cm inner diameter. Radial and axial current density measurements were made with charge collectors at axial fields of 0-5 kG. Focusing effects and spacial current density profiles are discussed