• P. Forck, E. Guetlich, R. Haseitl, P. Kowina
  GSI, Darmstadt

Scintillation screens are widely used for qualitative beam profile monitoring, but precise profile measurements yields ambivalent results for high beam currents. Moreover, these screens are an essential part of a pepper-pot emittance system requiring a quantitative profile evaluation. Therefore, we investigated the optical properties of 14 scintillating materials with different beams in the energy range 5.5 to 11.4 MeV/u as delivered by the heavy ion linac at GSI. Beside sensitive scintillators like YAG we focus on ceramic materials with lower light yield, like BN, ZrO2, Al2O3 and Al2O³⁺Cr. Their properties (light yield, beam width, high statistical moments etc.) are compared to different quartz glasses. The image of each macro-pulse is recorded by a digital CCD camera and individually evaluated by a high performance data acquisition system. For some materials, a decay of the light yield and an increase of the imaged beam width were observed. Moreover, the light yield depends on the screen temperature, which is significantly increased by the beam impact. A quantitative comparison under different beam conditions is presented.