Triggerless Micro Vertex Detector with low material budget in the PANDA experiment

Abstract

Besides the typical features characterizing the silicon detectors in the High Energy Physics such as good spatial resolution, energy loss measurement, limited material budget and radiation hardness, the Micro Vertex Detector (MVD) for the PANDA experiment (at the FAIR Facility in Darmstadt connected to the GSI Laboratory) is requested to cope with special issues. The expected study of many physics channels at high antiproton-proton annihilation rates (2·107 ann/s) is asking for a triggerless readout with a continuous data transmission and a good time resolution. The wide particle momentum distribution starting from some hundreds of MeV/c asks both a very limited material budget and a high dynamic range. The MVD is composed of: hybrid pixel (100μm ×100μm) detectors with thin silicon epitaxial sensor and readout developed by 130nm CMOS technology and double sided silicon strip detectors with supporting mechanics based on carbon fibres. Carbon foam layers will improve the heat transfer towards the cooling system based on water and working in vacuum-operated mode. Last developments in the MVD design and results concerning the prototyping phase are reported.