Speaker
Description
For the High-Luminosity LHC (HL-LHC), the Vacuum Assembly for eXperiments (VAX) of the ATLAS and CMS experiments required a major redesign to improve accessibility and reduce personnel exposure to radiation during its exploitation and maintenance. In the current LHC configuration, the VAX is located at a closed end of the tunnel, where the risk of oxygen-deficiency is also present. To address these safety concerns, the VAX modules have been relocated to the opposite side of the TAXS absorber, within the experimental cavern. This new layout enables fully remote installation, connection and removal of the VAX modules using a robot suspended from a crane, in line with ALARA (As Low As Reasonably Achievable) radiation exposure principles. It also allows the first quadrupole magnet to be positioned 833 mm closer to the interaction point, improving the final focusing of the beams before collisions.
This paper presents the design, prototyping, and production of the VAX, with a focus on the development of a key vacuum component: the DN80 universal joint bellows. Given the novel application of thin-film coatings to these elements, in particular the use of amorphous carbon (a-C), an emphasis is placed on the coating qualification.
| Paper status | Resubmitted proceeding files received and assigned to an editor. Accepted. |
|---|