The Einstein Telescope will open a new window on the Universe through the observation of gravitational waves. Its infrastructure will be buried 300 meters below the surface to reduce human-, wind- and ground-induced vibrations and movements.

The Interreg project E-TEST is a very important step of the Einstein Telescope, as it will be a proof of concept, both on the prototype side and on the geological side.

E-TEST will build a prototype – a large suspended mirror at cryogenic temperature (10 Kelvin) – to validate the telescope’s technology. E-TEST will also run an underground study to map and model the geology of the Euregio Meuse-Rhine.

This will allow to define the optimal design and location of the future Einstein Telescope. UCLouvain collaborates with the following institutes:
E-TEST full partners: Université de Liège, RWTH Aachen, UHasselt, Rheinische Friedrich-Wilhelms-Universität Bonn, NMWP Management GmbH, Fraunhofer-Gesellschaft für Förderung des Applied Forschung e.V., KU Leuven, Nikhef, KNMI, Maastricht University.
E-TEST satellite partners : Université Libre de Bruxelles, Vrije Universiteit Brussels, Universiteit Gent, Universiteit Antwerpen, Université de Mons.

The partecipation of UCLouvain in this project is possible thanks to support from the European Union through its Interreg EMR programme.

Interreg EMR programme website
E-TEST project website
Interreg EMR E-TEST project website


Academic staff

Research scientists


  • On Feb 1, 2020 the R&D EU Interreg project E-TEST officially started. It involves 11 institutes from Belgium, Germany and Netherlands and will carry on crucial detector developments for the Einstein Telescope (ET) - a 3rd generation antenna of gravitational waves, related mostly to cryogenic operations of large mass mirrors and their suspensions, ultra-precise metrology and sensing, as well as to advanced geological studies in the region (the ET is a deep-underground detector). The CP3 group is a partner in this project and is working on work package 1 : "Ultra-cold vibration control" and in particular on a cryogenic superconducting inertial sensor.

    Gravitational wave signals below a frequency of about 10 Hz are obscured by thermal noise in current detectors. Because temperature is the vibration of atoms in some respect, making the distance measurement between the mirror surfaces more challenging, the mirrors of future detectors will need to be cooled down to temperatures around 10 K. We need to control the motion of some of the cold objects, for which we develop inertial sensors that can survive this harsh environment.

    CP3 members collaborate mostly with RWTH Aachen (they are preparing a cryostat where we will test the sensor), KUL (we are collaborating to develop cryogenic readout electronics for the sensor) and ULiège (we align our sensor efforts).