Experimental Facilities

Attention SPL users Download, read and familiarize with the following before using the facilities General Laboratory Guidelines Vacuum System Procedures ASTROVAC Availability Chemical Inventory

The Space Propulsion Laboratory is equipped with a 1.5 1.6 m cryopumped and bakeable vacuum tank, capable of reaching ultimate pressures under 10-8 Torr, with a pumping speed of 7000 liters/sec of Xenon. This tank can accommodate additional hardware such as plasma diagnostic probes, particle detectors, etc. Several windows located around the chamber allow visual inspection of the working equipment.

Also in our Laboratory is a smaller vacuum facility explicitly dedicated to electrospray thrusters working in any of its three regimes of operation; droplets, ions or a mixture of both. It is pumped by two 70 liters/sec turbomolecular pumps, providing ultimate pressures of under 10-7 Torr. This tank houses our combined energy and specific charge analyzer using a combination of retarding potential and time-of-flight techniques. The turnaround time of this facility is fast, and ample signal, power and fluid feedthroughs have been provided.

A third vacuum chamber is installed next to our existing cryopumped system to improve the research and testing capabilities of electrospray thrusters, from single emitters to microfabricated arrays. Although small in size (30 cm in DIA), this chamber has ample accessibility through a variety of instrumentation feedthroughs.

The chamber is pumped down by a single 70 liters/sec turbomolecular pump, but since it is attached to the larger chamber through an isolation gate, the pumping speed can be increased to >5,000 liters/sec while adding the flexibility of using characterization instruments inside the bigger chamber, like a TOF spectroscope and/or a retarding potential analyzer. Inside the chamber there is a 3-axis translational stage with sub-micron resolution together with a micro-channel-plate/phosphor screen beam visualization system. These tools are used to determine the spatial structure of the emitted particles (positive and negative ions and neutrals) while changing the emitter-extractor geometry of the setup in-situ.

The laboratory is also equipped with a number of ancillary pieces of equipment, such as video microscopes, high-voltage programmable power supplies, nano-sec level programmable pulse generators, high-voltage amplifiers capable of receiving ns level pulses (for particle beam modulation), high Bandwidth (1-GHz) oscilloscope, vacuum roughing pumps, cold traps, etc.