Skip to main content




Quick Facts:

  • 16-ft diameter by 30-ft long
  • Base Pressure: 1.9×10-9 Torr
  • 7-ft diameter personnel entry door
  • 1500 liters LN2 storage vessel
  • 10 LN2 CVI TM1200 Internal Cryopumps
  • Chamber penetrations for power, data acquisition, and high-pressure liquids and gases
  • Chamber floor designed for a load of 2 tons
  • Large experiment assembly area


Vacuum Test Facility 2 is 9.2 meters long and 4.9 meters in diameter. One 3800 CFM blower and one 495 CFM rotary-vane pump evacuate the facility to moderate vacuum around 30 mTorr. To reach high-vacuum, the facility employs 10 LN2-cooled CVI TMI reentrant (nude) cryopumps that give the facility a nominal pumping speed of 350,000 l/s on xenon and a base pressure of 1.9×10-9 Torr; this is the highest xenon pumping speed at any University in the nation. To lower operating cost, the facility utilizes a Stirling Cryogenics SPC-8 RL Special Closed-Looped Nitrogen Liquefaction System with a reservoir capacity of 1500 liters of LN2.

A wide range of diagnostics may be employed in either of the large vacuum facilities. Two internal linear tables and one rotary table allow computer-controlled positioning of devices or diagnostics up to 100 kg. A High-Speed Axial Reciprocating Probe (HARP) system allows diagnostics to be taken inside a Hall Thruster discharge channel. An internally-mounted Hiden EQP-300 probe allows for simultaneous velocity, energy, and species measurements on both ions and neutral atoms. The thrust stand is a duplicate of the proven null-type inverted-pendulum thrust stand used to test high-power Hall thrusters at the NASA Glenn Research Center. The thrust stand is actively cooled by a VWR Polyscience 1171 recirculating chiller. The facilities can be configured to accommodate a wide variety of experiments. The total area of combined lab and office spaces is in excess of 4,000 sq. ft.