Transverse BIF Profile Monitor - System Development for FAIR

The planned facility for antiproton and ion research FAIR at GSI will accelerate high intensity beams from protons to Uranium ions in the energy range of 100 MeV/u to 30 GeV/u. In the transport lines between the synchrotrons and in front of production targets precise alignment is required. Conventional intercepting diagnostics will melt due to the beam energy deposition. For transverse profile determination, we investigate a non-intercepting Beam Induced Fluorescence (BIF) Monitor. The residual gas N2 is excited to fluorescence levels by atomic collisions with beam ions. By single photon detection via a double MCP image intensifier coupled to a digital CCD camera the beam profile is determined [1]. The BIF method was applied successfully at the GSI heavy ion LINAC for various ion species and energies between 4 and 11.4 MeV/u [2]. Now we investigate its application for higher energies as extracted from the heavy ion synchrotron SIS-18 [3]. Our experimental studies aimed to determine the photon yield and background contribution for different ion species (Xe, Ta, U) at beam energies from 60 to 750 MeV/u. In Fig.1 the signal amplitude (top), background level (middle) and signal to background ratio (bottom) are plotted as a function of energy. The measured signal strength corresponds to a Bethe-Bloch fit. The measured background level corresponds to the calculated cross section of neu-