Speaker
Description
We present a dual-tunnel architecture as an alternative to large cavern halls. It comprises raise-bore wells and an upper service tunnel. By anchoring the heads of the seismic attenuation chains directly to bedrock the seismic motion amplification of tall towers is eliminated and the area around the optical components decluttered. Individual access can be provided to all seismic attenuation filters, thus simplifying installation, tuning and maintenance. Longer pendulums are possible, with lower frequency resonances. The vicinity of the walls allows to use the rock as reference to damp the pendulum modes down to below the Peterson’s low frequency model, which simplify lock acquisition, greatly reduce the required actuator’s authority and thus mitigate the control noise. Sensors attached to the vertical rock walls allow separation of seismic translation from tilt for inverted pendulum correction and for advanced Newtonian noise cancellation. The excavation volume is reduced by at least an order of magnitude.