Development of Fast and Radiation Hard Monolithic Active Pixel Sensors (MAPS) Optimized for Open Charm Meson Detection with the CBM Experiment

Résumé du livre

The Compressed Baryonic Matter experiment (CBM) will investigate heavy ion collisions at beam energies between 10 and 40 AGeV in order to explore the nuclear matter phase diagram in the high baryon density region. For a first time, open charm mesons (D0 and D±) will be used as probe for the nuclear fireball. Reconstructing them requires a very thin (few 0.1 % X0 per layer) micro vertex detector (MVD) with pixel sensors featuring excellent spatial resolution (few μm) and substantial radiation hardness. This work studies whether (and how) an MVD based on the novel Monolithic Active Pixel Sensors (MAPS) can the reach the performance needed. For this purpose, the precise requirements on the MVD in terms of material budget, cooling, time resolution and radiation hardness were estimated. Extensive R&D studies on MAPS allowed establishing their performances in particular in the field of radiation tolerance and to improve this tolerance by one order of magnitude. The information obtained was used as input for a GEANT simulation which demonstrated the feasibility of open charm physics with the proposed detector concept.