Filippo Bosi

Measuring Gravito-magnetic Effects by Multi Ring-Laser Gyroscope

SUMMARY We propose an under-ground experiment to detect the general relativistic effects due to the curvature of space-time around the Earth (de Sitter effect) and to rotation of the planet (dragging of the inertial frames or Lense-Thirring effect). It is based on the comparison between the IERS value of the Earth rotation vector and corresponding measurements obtained by a tri-axial laser detector of rotation. The proposed detector consists of six large ring-lasers arranged along three orthogonal axes. In about two years of data taking, the 1% sensitivity required for the measurement of the Lense-Thirring drag can be reached with square rings of 6

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

m

The GINGER project and status of the GINGERino prototype at LNGS

side, assuming a shot noise limited sensitivity (

A laser gyroscope system to detect the gravito-magnetic effect on Earth

20 prad/s/\sqrt{Hz}

Position sensitive silicon detectors inside the tevatron collider

). The multi-gyros system, composed of rings whose planes are perpendicular to one or the other of three orthogonal axes, can be built in several ways. Here, we consider cubic and octahedron structures. The symmetries of the proposed configurations provide mathematical relations that can be used to study the stability of the scale factors, the relative orientations or the ring-laser planes, very important to get rid of systematics in long-term measurements, which are required in order to determine the relativistic effects.

Rotational sensitivity of the G-Pisa gyrolaser

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. Several days of continuous measurements have been collected, with the apparatus running unattended. The power spectral density in the seismic bandwidth is at the level of 10-10 (rad/s)/Hz. A maximum resolution of 30 prad/s is obtained with an integration time of few hundred seconds. The ring laser routinely detects seismic rotations induced by both regional earthquakes and teleseisms. A broadband seismic station is installed on the same structure of the gyroscope. First analysis of the correlation between the rotational and the translational signal is presented.Large ring-laser gyroscopes are capable of measuring angular rotations with a precision well below fractions of

High sensitivity rotation measurements with a mid-size laser gyroscope

prad/s

Construction and performance of silicon detectors for the small angle spectrometers of the collider detector of fermilab

, not far from

A network of heterodyne laser interferometers for monitoring and control of large ring-lasers

10^{-14}