Effect of time-varying magnetic field on the properties of the annular anode plasma jet

The paper presents the properties of anodic plasma jet in the presence of a time-varying magnetic field. The dense anodic plasma jet is produced by significantly reducing the area of the anode compared to the cathode. The cathode has a cylindrical geometry with a length of 5.0 cm and inner diameter of 10.0 cm. The annular anode has a diameter of 1.0 cm. The significant reduction in the area of the anode as compared to the cathode leads to a two orders of magnitude enhancement in the electron density in the anodic region. The downstream plasma in the anode region is characterized by an oscillatory double layer structure with the oscillation frequency in the range of 10 to 100 kHz. The time-varying magnetic field with a peak value of 0.2 T is applied 1.0 to 2.0 cm away from the anode surface, and time-resolved plasma densities, plasma potential, and electron temperature measurements are carried out using electrical probes. The ambipolar diffusion model is presented to explain the experimental results.