Operation of semiconducting detectors, especially CdZnTe-semiconducting-detectors, immersed in liquid scintillator with the purpose of searching for rare processes, dominantly the double-beta-decay

• Applicants: Professorin Dr. Caren Hagner; Professor Dr. Kai Zuber
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2009 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 139253166

The search for rare events like the neutrinoless double beta decay or WIMP scattering allows us to adress fundamental questions of particle physics. Experiments like this are especialy sensitive to backgrounds and thus need a complete understanding of backgrounds and effective ways to reduce them.For this reasons, we want to study within this work weather nonpassivated CdZnTe-seminconducting-sensors can be operated in liquid scintillator and how much this would help to reduce the background. Background reduction is expected due to the passive properties as a shielding , its high radioactive purity and the possibility to use it as a veto. Within this context CZTs are of particular interest for two reasons: They can be operated at room temperature and they contain several isotopes which could undergo the neutrinoless double beta decay or related processes.So far, the operation of CZTs in FS was successfully tested within this project and a simulation environment for the experimental setup was implemented using Geant4. However, to establish the experimental fundamentals for a possible full scale experiment using this scheme, long term studies of the behaviour of both the CZTs and the FS under this conditions are necessary. In addition, it is important to analyse the expected background for example from neutrons or cosmogenic isotopes. For instance it is possible that radioactive Ions are attracted by the electrodes of the CZTs during operation, which would lead to an increased background rate.

• DFG Programme: Research Grants