LISA Charge Management Device: environmental testing for TRL6

The Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational waves observatory. Gravitational waves are ripples in the fabric of space-time caused by highly energetic events in the universe. LISA will detect lower-frequency gravitational waves by tracking the relative changes in distance between the free-falling test masses (TM) enclosed within each spacecraft. Coupling of a charged TM and electric fields results in electrostatic forces, causing acceleration noise. Because this noise would hinder the sensitivity of the science measurement, a Charge Management Device (CMD) is implemented to discharge the TM using the photoelectric effect. Within the CMD, the UV Light Unit (ULU) provides the ultraviolet light for the discharge.

The University of Florida was tasked with the CMD design, and it is now performing verification testing for Technology Readiness Level (TRL) 6 for the ULU, consisting of shock, vibration, and thermal vacuum between -30 °C to +60 °C. This presentation will cover the results from testing, supported by Ground Support Equipment, which allows to investigate the parameters of the UV light output, and to characterize the ULU performance to ensure LISA requirements are met.