The machine shop and design engineering department is developing and constructing mechanical components of experiments, test stands, tools for detector construction as well as special apparatuses, together with various project groups. The focus lies on construction, simulation, production as well as installation and commissioning.

The typical process of a task requires a few iterations with the clients, because initially there are usually some open questions which only get settled in the course of the project. This would make it extremely difficult to outsource those tasks to external companies.

In the following, we list a few examples of tasks for current projects.

Belle II: Mechanical Design of the Silicon Vertex Detector

HEPHY is a leading participant of the Silicon Vertex Detector (SVD) of the Belle II Experiment and – among other fields – responsible for the mechanical design and cooling of the device. Consequently, the full detector was constructed in 3D CAD, parametrized and optimized considering the requirements of physics. Specific aspects were simulated with the Finite Element Method (FEM) and subsequently improved.

Belle II: Silicon Vertex Detector Assembly Jigs

Highly complex Silicon Detector modules (so called “ladders”) for the Belle II experiment were built in a clean room at HEPHY. This requires about 20 different jigs which must feature a precision of a few thousandths of a millimeter in order to allow ladder assembly with the required accuracy. All jigs were designed in the HEPHY machine shop and largely also manufactured here – this was possible in all but three cases with the existing machinery.

Belle II: Silicon Vertex Detector Ladder Mounting

The modules of the Silicon Vertex Detector of Belle II were manufactured at five different institutes – among them HEPHY. With the help of HEPHY members, those modules are mounted on a support structure at KEK (Tsukuba, Japan), measured for spatial precision and electrically tested at both room temperature as well as at about -10°C. The cooling is established by a CO2 system developed at HEPHY, which is described in the next section.

Belle II: CO2 Cooling

In recent years, CO2 has become quite popular as a coolant in particle physics (and also in the commercial world), because – in contrast to previously used refrigerants it is non-toxic and at the same time highly efficient. We have built a so-called open CO2 cooling system named “AC/BC”, which is currently used in Japan for cold tests of the installed Silicon Vertex Detector ladders (see previous section).