===== OTR with Image Intensified Camera System =====

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After first testing with a simple CCD, a custom designed Proxitronic image intensified camera system #18804 was used for further investigation of OTR. The system is specified as follows:
  * Bialkali photocathode (200 - 600 nm)
  * V-stack double Multichannelplate (diam. 25mm)
  * P46 Phosphor (decay 90%-10% in 300ns)
  * Relay-Optic coupling (β 0.6)
  * AVT Marlin CCD, monochrome, vga resolution

This setup enables single photon counting and fast triggering. A timing window of 100 ns could be used even for low currents, still achieving reasonable signal. The following was investigated:
  * Shifted 50µs time-window to measure the change of OTR signal before/ during/ after the beam pulse >> thermal afterglow could be for sure excluded !
  * OTR signal comparison for polished stainless steel and for aluminium foil (10µm Al on Kapton)
  * Current variation between 0,2µA and 10µA (1,4 E+07 - 7 E+08 ppp)
  * OTR signal for different thicknesses of stripping foils (carbon: 370 µg/cm² ;  571 µg/cm² ;  563 µg/cm²)

===== Results =====

First of all the data was analysed to see roughly the dependency of the light yield to the ion charge state.

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