| Paper | Title | Page |
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| TUPSM019 | Light Yield, Imaging Properties and Spectral Response of Inorganic Scintillators Under Intense Ion Irradiation | 151 |
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Scintillating screens are widely used for transverse beam profile monitoring and pepper-pot emittance measuring instruments at accelerator facilities. For high current beam operations at the GSI heavy ion UNILAC, several inorganic scintillators were investigated under different ion beam conditions in the energy range from 4.8 to 11.4 MeV/u and currents up to some mA. The imaging properties of various scintillating screens were studied with respect to light yield and imaged beam width, i.e. important parameters for precise beam profile measurements. The measured light yield and beam width show a strong dependence on the scintillating material and change significantly with screen temperature. The spectral response of the materials was mapped for different temperature levels, using a spectrometer in the visible and near UV range. The results clearly demonstrate that the scintillating properties of the materials, and their temperature, are critical issues for high current operations and have to be taken into account for correct beam profile reading. |
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| TUPSM020 | Beam Induced Fluorescence Monitor–Spectroscopy in Nitrogen, Helium, Argon, Krypton, and Xenon Gas | 156 |
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As conventional intercepting diagnostics will not withstand high intensity ion beams, Beam Induced Fluorescence (BIF) profile monitors constitute a preeminent alternative for non-intercepting profile measurements. This diagnostic technique makes use of optical emission of beam-excited gases. Recently BIF became an important diagnostic technique for beam profile measurement with applicability in beam tuning over a wide range of beams and accelerator conditions. Beam induced fluorescence spectra in the range of 300 - 800 nm were recorded with an imaging spectrograph for 5 MeV/u proton, S(6+) and Ta(24+) beams in nitrogen, Xe, Kr, Ar, Ne and He at 10-3 mbar gas pressure. Optical transitions were identified and associated with corresponding beam profiles. Effective light yields, normalized to the differential energy loss, are presented for all gas-species investigated. Since residual gas ionization is the basic process for BIF-monitors as well as for Ionization Profile Monitors (IPM), BIF-results are compared to IPM measurement data. |