Long Jidong

Characteristics of Resistance Triggering of a Pulsed Vacuum Arc Ion Source

Triggering scheme is a significant factor that may influence the process of vacuum arc initiation. In this work, the characteristics of resistance triggering of a pulsed vacuum arc ion source are investigated and compared with the independent pulse generator triggering. The results show that although the resistance triggering method is capable of triggering a vacuum arc ion source by properly choosing the resistance and electric parameters, it inevitably increases the rise time of the arc current. A high speed multiframe camera is used to reveal the transition process of arc initiation during one shot. From the images it is conjectured that the lower voltage between the cathode and the anode may be the reason that leads to the lower transition speed of discharge at the moment of arc initiation.

Ion beam profile diagnosis methods for vacuum arc ion source in sealed tube neutron generator

The ion beam for vacuum arc ion source in sealed tube neutron generator owns some special features, such as multi-particle mixtures, high-intensity beams, short pulse-width, short transport-distance and asymmetric beams. It is related to the design of the vacuum arc ion source and beam optics, which affect the insulation withstand of the device, the life of tritium target, the neutron yield, and so on. It is important to obtain information on ion beam profile in researching of the sealed tube neutron generator.

Parametric investigation of a mid frequency internal oscillating currents driven plasma reactor

Summary form only given. A novel inductively coupled mid frequency (2 MHz) plasma source with orthogonal coil configuration is presented. The inductive coil consists of two perpendicular copper rod layers inside the chamber to improve the power transfer efficiency and uniformity of plasma. The results of magnetic field distribution under low and high plasma density are reported in detail. It shows that the radial uniformity of magnetic field and plasmas is enhanced significantly compared with that of external planar coil in 460 kHz frequency. Depending on the input power, the plasma source can operate in either the electrostatic (E) mode or electromagnetic (H) mode discharge. It is interesting that the mode transition can be continuous or discrete. The mode transition jump is obvious in 460 kHz with the same inductive coil and chamber. Furthermore, the required input power to initiate the discharge is observed remarkably low (10 W) in the present chamber with a volume of 18.5 litres