Speakers
Description
For the High-Luminosity LHC, CMS will install a completely new silicon tracker. The future tracker will consist of two barrel parts and two endcaps (TEDD), one on each side. One TEDD is made of five double-disks, each equipped with detector modules on all four faces to ensure a complete coverage. The backbone of the mechanical structure of the TEDDs are highly integrated half-disks, the so-called Dees.
A Dee consists of a carbon fiber sandwich with a foam core and embedded cooling pipes, and module positioning inserts. A prototype in the size of one cooling sector (1/6 of a Dee) is currently being built, implementing lessons learned from previous design iterations. This prototype will be used to further develop and qualify the manufacturing process, verify production tolerances and exercise the planned reception tests, such as metrology and thermal imaging. As the prototype includes the section of a Dee that overlaps with its matching Dee in a disk, it will be also used to verify the disk assembly concept and tooling. Full size prototypes are also planned to demonstrate the production capabilities and exercise the final integration and assembly procedure.
After the Dees are equipped with modules and tested, they are combined to form disks, double-disks and finally the TEDD. With the Dees being lightweight but large and fragile objects, they need to be supported during assembly and integration. A large semi circular arc frame is being designed to support the detector parts during all necessary integration steps, which includes transport, thermal cycling and relative positioning to a high precision. For the integration, tooling to precisely align the different disks is needed before installing the connecting skeleton. Dedicated assembly stations are being designed to allow sub mm precision alignment.
The contribution will give an introduction into the design of the TEDD and the Dees. The status of the ongoing prototyping and R&D for the half-disks and details about the planned reception tests for the production of the final Dees will be presented. The plan for an assembly sequence will be discuss. The designs and prototypes for toolings to build double-disks and the final TEDD will be presented.
