An Intensity Measurement Method based on Inorganic Scintillators and Optoelectronic Sensors

The Heidelberg Ion Therapy Center (HIT) is a heavy ion accelerator facility located at the Heidelberg university hospital and intended for cancer treatment with heavy ions and protons. Currently ionization chambers with highly sensitive charge amplifiers are regularly used for intensity measurements of the high-energy ion beams. A new intensity measuring method will be presented based on the combination of fluorescent light from inorganic scintillators and an optoelectronic sensor with adjacent electronics as an alternative to the ionization chambers. A special measurement set-up with a large-area Si PIN-diode and adapted optics was investigated with respect to signal dynamics, resolution and linearity. The experimental results with proton and carbon beams will be presented in detail. Worth mentioning is a variation in sensitivity relating to the position of the beam spot, which could be reduced to some percent only.
Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany