Air ionization in self-neutralizing air-breathing plasma thruster

The paper describes an arc electron source for air ionization applications in a self-neutralizing air-breathing plasma thruster. The arc electron source is an electron source with a prominent level of electron energy control that is required for the air-breathing plasma thruster. The mean energy of the electrons in the arc electron source is controlled by changing the grid voltage in the range of 0 V-300 V. The Langmuir/Faraday probes were used to obtain ion/electron current, electron temperature, and electron density as a function of pressure and electron energy. Ion current measurements concerning distance from the source were obtained as a function of pressure and grid voltage. Optical emission spectroscopy was used to obtain electron temperature, spectral intensities, and ion formation rate. Additionally, a drift tube based on radial magnetic field electron confinement was designed to detect the presence of negative ions. It has been shown that both positive and negative ions can be produced thus providing conditions for a self-neutralizing air-breathing plasma thruster.