Imaging Properties of Scintillation Screens for High Energetic Ion Beams

The imaging properties of various scintillation screens were investigated for ion beams extracted from the heavy ion synchrotron SIS 18 at GSI. Different ion beams such as C, Ne, Ar, Ta and U with initial kinetic energy of about 300 MeV/u were applied to various scintillation screens with particle fluxes ranging from 10⁴ to 10⁹ particles per pulse typically within 0.3 s pulse length. The scintillation process was observed with a digital Charge Coupled Device (CCD) camera. The performed study compares the light output, the beam profiles, and the image deformation of various scintillating screens for different ion beams. The light output scales linearly with respect to the ion beam flux over five orders of magnitude for the sensitive scintillation screens and ceramics like Al₂ O₃ , Al₂ O₃:Cr. The highest light output was observed for CsI:Tl, and the lowest was recorded for Herasil. At higher beam intensities, non linear behavior of light output was observed for Mg and Y doped ZrO₂ samples. The recorded beam profiles showed differences in width up to 50%, depending on the screen material.