A lot of talk has been going around about the prototype for a new generation of gravitational wave detector: ETpathfinder. And now, after many months of careful planning and preparation, the first visible steps towards realisation are finally complete.
The location of this innovative laser-interferometer is the former transport hall of a local newspaper. The concrete floor that will serve as a low-vibration base for ETpathfinder is poured and drying as we speak.
ETPathfinder will be a testbed to measure incredibly small length changes, equivalent to a tiny fraction of the size of a proton. To achieve this mindboggling sensitivity ETpathfinder has to sit on a floor that is extra stable.
ETpathfinder project leader Stefan Hild explains: “In order to make the floor very stable, it sits on 169 pillars which have been drilled into the ground and it is made out of two separate parts: The other part is connected to the building itself with all its noise from ventilation system and humans, and then there is an inner part of the floor on which the core of ETpathfinder will sit. Splitting the floors guarantees that ETpathfinder will not feel any of the movement of the building itself and for instance the wind pushing against the building walls and therefore move the ground.”