The G-0 ring laser
As a result of the Canterbury Earthquakes the Cashmere Cavern/ Cracroft Caverns Laboratory is currently closed.
G-0 is a 3.5 m x 3.5 m square ring laser located at the Cashmere Cavern Laboratory and mounted vertically on one of the existing concrete walls. The main reason for constructing G-0 was to further the work done by C-2 in preparation for construction of the Gross Ring. While constructed using much cheaper materials than C-2, G-0 provided insight into issues of extrapolating to a much larger size.
G-0 has successfully measured fluctuations in earth rotation to an accuracy 10 parts per million of the base rate. When working in conjunction with C-2, the rotational effects of teleseismic waves have been detected. Its vertical orientation is an added bonus for geophysical studies as it measures Rayleigh (vertically polarised) waves, whereas C-2 measures Love (horizontally polarised) waves.
The current intention for G-0 is to run the laser in 'observatory mode', this means providing a continuous record for the geophysical community. As our program has thus far essentially been in a development phase with changes often being made to the instruments, a continuous long term record has not been previously available.