Gyroscopic performance and some seismic measurements made with a 10 meter perimeter ring laser gyro housed in the Ernest Rutherford building.

We describe the construction and operation of a large ring laser whose beam paths enclose an area of 6.25. The gyroscopic performance of this large laser interferometer was determined using laser operation at a wavelength of 632.

Reconstruction of the Instantaneous Earth Rotation Vector with Sub-Arcsecond Resolution Using a Large Scale Ring Laser Array.

Absolute rotation rate sensing with extreme sensitivity requires a combination of several large scale gyroscopes in order to obtain the full vector of rotation. We report on the construction and operation of a four-component, tetrahedral laser gyroscope array as large as a five story building and situated in a near surface, underground laboratory. It is demonstrated that reconstruction of the full Earth rotation vector can be achieved with sub-arcsecond resolution over more than six weeks.

Deep underground rotation measurements: GINGERino ring laser gyroscope in Gran Sasso.

GINGERino is a large frame laser gyroscope investigating the ground motion in the most inner part of the underground international laboratory of the Gran Sasso, in central Italy. It consists of a square ring laser with a 3.6 m side.

High-accuracy absolute rotation rate measurements with a large ring laser gyro: establishing the scale factor.

Large ring lasers have exceeded the performance of navigational gyroscopes by several orders of magnitude and have become useful tools for geodesy. In order to apply them to tests in fundamental physics, remaining systematic errors have to be significantly reduced. We derive a modified expression for the Sagnac frequency of a square ring laser gyro under Earth rotation.

Recording and interpretation/analysis of tilt signals with five ASKANIA borehole tiltmeters at the KTB.

In June 2003, a large scale injection experiment started at the Continental Deep Drilling site (KTB) in Germany. A tiltmeter array was installed which consisted of five high resolution borehole tiltmeters of the ASKANIA type, also equipped with three dimensional seismometers. For the next 11 months, 86 000 m(3) were injected into the KTB pilot borehole 4000 m deep.