A Study of the Thrust Generated by a T6 Hollow Cathode

The thrust produced by a T6 ion engine hollow cathode has been measured using a target-based system, with argon, krypton and xenon as propellants, for discharge current values of 5-25 A and a wide range of mass flow rates. The calculated values of specific impulse, which are generally higher for lighter gases, are far in excess of those that could be attributed to heating a gas to thermal equilibrium with the walls. This seems to suggest an arcjet-like operation mechanism.