Operating the Helicon Double Layer Thruster in a Space Simulation Chamber

A prototype of the helicon double layer thruster (HDLT) is designed and manufactured. Initial tests with the thruster mounted on a small vacuum chamber (pumping speed of 700 l ldr s^-1) show successful operation in xenon with the formation of the double layer which generates a low divergence ion beam, which is the source of thrust. The prototype is subsequently inserted inside a much larger space simulation chamber (pumping speed of 7000 l ldr s^-1). A high-density blue mode is found when increasing the RF power above 380 W, and measurements with a Langmuir probe give an estimated density of 10¹² cm^-3 in the thruster. An image of the HDLT operating in the high-density blue mode is presented.