Cryopump Chamber

This test facility consists of a non-magnetic stainless steel chamber approximately 1.5 m in diameter and 3.3 m in length. The chamber is pumped by a pair of two-stage cryogenic pumping systems (CVI-TM1200). The cryopumps are backed by a mechanical pump. In order to enhance the efficient use of this chamber, a 1.5m gate valve has been installed to isolate the test section from the cryopumps; in this way, the cryopumps can remain operational with the gate valve closed while adjustments are made in the test-section. Once any changes have been made and the chamber door closed, a turbo pump is used to reduce the test-section pressure. The gate valve is then opened to expose the cryopumps and reduce the test section to operational pressures. The pressure during typical thrust measurements is approximately 3×10-4 Pa, measured using an ionization gauge uncorrected for Xenon.







Lil' Cryopump

This test facility consists of a non-magnetic stainless steel chamber approximately 0.6 m in diameter and 1.2 m in length. The chamber is pumped by a single 50 cm diameter cryopump (CVI-TM500) backed by a ~60 L/s mechanical pump. The base pressure of the facility is approximately 10-4 Pa, as measured by an ionization gauge, uncorrected for xenon. Thruster testing at xenon flow rates of 0.12-0.20 mg/s results in chamber background pressure of approximately 10-3 Pa.