Micromegas for CLAS12 – Preliminary work on integration Central tracker Micromegas scheme Forward Vertex Tracker F. Sabatié CLAS Collaboration Meeting Feb. 19-24th 2008
Central Tracker scheme Electronics integration was done using existing aspect ratios (T2K-AFTER). Expect 30% redution in size and power consumption 3 layers of MM (each X,Y) 2 layers of Si FVT is included (basic MM solution, 3x2 planes) 2 schemes were examined: Half of the electronics is downstream (shorter paths to electronics, safe) All the electronics is upstream (obvious advantages but long path to electronics => needs testing) Only basic integration work was done. Need to add the possibility to remove Si without touching MM. Need to add cryo-target integration. Half-upstream All upstream
Central Tracker scheme cooling system for forward detector PCB extension cables for FVT Cables, gas, cooling, etc SVT For now, cylinder divided into 3, all the dead zones are aligned. For the FVT, they are also divided into 3 but each is shifted by 60°. MM FE electronics
Integration of the « all upstream » solution inside the magnet FVT can be integrated at the end of the cylinders in the case of MM design (PCB extension cable can make a 90° angle wrt the MM boards).
« All upstream » integration solution: some remarks So far no optimization of dead zones on the detector or the structure was studied (we know how to build all that, needs no R&D). Structures are in Aluminum, final detector will use lighter material. Electronics is based on T2K-AFTER, but size/comssumption is pessimistic because not optimized. For the final detector, expect a >30% gain in volume and dissipation + more appropriate connectors. HV distribution can also be highly optimized Basic concept to keep: Light cylindrical structure with MM laying on them and forward planes (which can be installed right at the end of MM cyl.), everything laying on a sliding structure for integration by the rear (target then Si and MM). Front End electronics needs to stay close to MM so cylinder has to be longer than the MM themselves. They will also integrate all necessary gas/cables/cooling entries/exits. Glycol distribution system for electronics cooling is mandatory. Holding of the central tracker is further behind because of TOF. Integration of Si and MM on the same holding structure has to be seriously studied in 2009-2010 if mixed solution is chosen (needs more work before).