Presentation #533.02 in the session “Radio, mm and sub-mm Instrumentation and Performance”.
The primary reflector of the Green Bank Telescope is composed of 2004 panels that form a 100 m diameter dish. These panels can be adjusted in real time to reach the surface accuracy required for efficient high frequency observations. In order to speed up the measurement of deformations of the primary reflector the Green Bank Observatory is investigating the use of a commercial terrestrial laser scanner, the Laser Antenna Surface Scanning Instrument (LASSI). LASSI was installed on the GBT the fall of 2020 and is currently under commissioning. In this contribution we present the latest results from the instrument, including the measurement of deformations of the order of 75 microns.