Investigation of an annular magnetically insulated ion diode operated in long pulse mode

The diode mechanism was studied in an annular magnetically insulated ion diode operated in long pulse mode. Average length of electron drift by E×B force in the gap is measured to be about 30 to 60 mm. Based on fundamental theory, the ion production efficiency is estimated by this length consistent with the experimental value(20 to 40%). It is found that we can optimize the azimuthal drift length of electrons and simultaneously the anode plasma formation by adjusting the shape of insulation magnetic field. Titanium hydride was used as anode material. It becomes known that not only surface flashover but also electron bombardment on anode surface makes fair amount of anode plasma in this long pulse diode.