The first 18 metre long section of the decay tube has been installed and concreted. This operation, taking place at the transition of the decay tunnel and the hadron stop chamber, was completed on 18 November 2003.

This first section of the decay tube was welded from three 6 metre long sleeves in the workshop in TCC4, the CNGS target chamber. Since the end of the decay tube will be closed of with the exit flange once the full tube is installed, the last piece of tube is equipped with a transition section, which was also welded onto the tube in TCC4.

Installation of the decay tube is now expected to continue in a regular rythm: 6 metre long sleeves are lowered into the access gallery through the provisional civil engineering shaft and transported to the target chamber. Assembly into 18 metre long section and checking of welds should take place in TCC4. Sections of 18 metres are welded together in the decay tunnel, and concrete is poured around the tube as it is constructed from bottom to top. 

                 
Workshop in the target chamber - assembly of the 18 metre long decay tube sections

First (most downstream) section of decay tube at its destination, before concreting

Additional sleeves on the work-site