Installation of an HPWREN-connected High Precision Ring Laser at the Pinyon Flats Observatory

A newly developed high precision ring laser was recently deployed at Pinyon Flat Observatory (PFO) in southern California.�This new type of sensor measures rotational motion and is designed by Dr. Heiner Igel and Dr. Ulrich Schreiber from respectively, Department of Earth and Environmental Sciences, LMU Munich, and Fundamentalstation Wettzell, K�tzting. These new sensors have a sensitivity that can measure 10^-9 of Earth's rotation (6 nrad/d)2*10^-10 rad/s to 7.6 rad/s for frequencies up to 20 Hz or higher.�Two more of these devices are currently successfully deployed, one in Germany and one in New Zealand.

Ring laser in its working state after installation.

During the Fall of 2003 we had several meetings with Dr. Igel and Dr Schreiber at UCSD, the Fall AGU, and at PFO, to review possible locations for deployment of a third high precision ring laser.�The PFO site was proposed for deployment since it is a quiet site and already has the IDA Global Seismic Network station, the ANZA regional network station, and the Pinyon Flat Long Baseline Laser Strainmeters located there. The IDA and ANZA seismic stations, and PFO strainmeters have been continuously running for more than 20 years providing a good characterization of seismic environment and the level of teleseismic, regional, and local seismicity observed at PFO. Pinyon Flat also has the distinct advantage that it is reachable through the NSF-funded High Performance Wireless Research and Education Network providing high speed Internet connectivity for near real-time data acquisition to the PFO site. In addition, a new seismic vault test facility was funded last year through NSF, Green Foundation, and SIO funds which will house the IDA and ANZA equipment upon its completion later this year.�Construction on the vault facility is nearly complete.�In the design plans for the vault facility there are four rooms.

Current state of construction for new PFO vault. The ring laser is in the upper right room.

The German team arrived at UCSD on January 17, 2005.�After a short planning meeting the truck was loaded and the trip was made to PFO.�On the fourth day of the installation, the ring laser achieved "first light" at 23:30 GMT on January 20. The installation and testing was completed by February 2.�All that is left to do at the site is to complete the vault construction at PFO and bury it underground to get the temperature stability necessary for the high precision ring laser observations.

-- Dr. Frank Vernon IGPP, UCSD