Mainz 2012 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HK: Fachverband Physik der Hadronen und Kerne

HK 5: Instrumentation

HK 5.4: Talk

Monday, March 19, 2012, 15:00–15:15, P 3

Aspects and Implementation of Stimulated Recovery for the PANDA EMC * — •Till Kuske, Valera Dormenev, Rainer Novotny, and Rene Schubert — Justus-Liebig Universität, Gießen

The future Electromagnetic Calorimeter (EMC) of the PANDA detector at FAIR will be based on a new generation of lead tungstate crystals (PWO-II). It is optimized to measure particle energies from 10 GeV down to 10-20 MeV. The operating temperature of the EMC will be -25°C. Due to the operation in a strong radiation environment one of the most critical parameter of PWO-II is radiation hardness. The radiation damage of PWO-II can be compensated by spontaneous relaxation of the color centers via thermo-activation. The process is strongly suppressed at -25°C, which is limiting the energy resolution of the EMC. The recovery process can be accelerated by illumination of the crystal with light even in the infrared region. The new results of the stimulated recovery under light illumination with different intensity in parallel (online mode) and after (offline mode) γ-irradiation at different temperatures is presented. The possible implementation of the stimulated recovery in both modes for the PANDA EMC is discussed. A recovery model based on the results will be presented.

*The work is supported by BMBF.