Speaker
Description
The lead tungstate crystal (PbWO4, PWO) is one of the widely used scintillation materials for electromagnetic calorimeters in high energy physics experiments. The degradation of the optical transmittance in the range of the luminescence spectrum under ionizing radiation leads to losses of the light output resulting in the deterioration of the energy resolution and limiting the life time of the calorimeter. A possible way to restore radiation damage is the in-situ illumination of visible or near infrared light of the whole crystal volume. It allows to recover the transmittance losses due to the depopulation of the color centers. Such kind of stimulated recovery subsystem based on a blue light emitting diode is considered for the electromagnetic calorimeter of the PANDA detector at FAIR (Darmstadt, Germany). Here we report on the stimulated recovery studies of the lead tungstate radiation damage induced by external light from laser diodes at different wavelengths. The level of technological development of laser diodes allows to increase the efficiency of the stimulated recovery.
