Development of inorganic scintillating fibres made of LuAG:Ce and LYSO:Ce

Similar to the field of application of fibers based on plastic scintillators, there is a strong interest to replace the materials by inorganic crystals. They will provide significantly higher light yield, an efficient interaction with electromagnetic probes due to the content of high-Z elements, a wider range of emission wavelength to adapt to the appropriate photo sensors and remain more resistant to radiation damage for long-term application. Based on the micro-pulling down technique the collaboration has focused on the optimisation of the technology and the quality inspection of fibres based on LuAG:Ce. There has been significant progress in the variation of the geometry, pulling several fibres in parallel, the optimisation of the crucibles and the requirements for increased efficiency for future mass production. In spite of the more challenging growing conditions the R&D program has been directed towards fibres made of LYSO:Ce. The very radiation hard and bright scintillator material appears to be very attractive for many applications in particular due to its very short radiation length. Fibres with 1 mm diameter and more than 100 mm length have been successfully produced and they show very promising performance. The paper will discuss in detail measurements of the achieved light output and homogeneity.