1. Results from the PMT test bench in BCN (10-Oct-03) J.Garra, R.Graciani, E.Graugés, X.Xirgu

2. 8 stage PMT CFD base: The output of 1 channel studied to perform a premilinary analysis on: Signal Shape Gain Number of photo-electrons

3. CFD active base

4. Signal Shape Some oscillations in the signal shape are supposed to be caused by some connection(?) problem.

5. Gain vs Photo-Statistics Possible saturation effects might be observed starting around 50 phe and above

6. Gain Our desired HV working point should be ~ 600 Volts obtaining an approximate gain of 30k to 50k

7. 8 stage PMT BCN base: A preliminary study has been performed with a LED source (no fibre) Gain and Photo-statistics have been looked at from the output of a 1 channel (#64) Now the setup is ready to get measurements for all the channels at once. Fatal accident ended up with the 8-stage PMT becoming unusable anymore

8. BCN active base

9. Signal Shape

11. The oscillations present in the first attempt (CFD) could be partially removed (with the BCN base) by when the setup has been re- done very carefully and assuring a common grounding for the (ADC/Black Box/Active Base) system. Still to be tried if that also cured the oscillation observed using the CFD base

12. 12 stage PMT This PMT has already incorporated the active base by Hamamatsu together with the (PMT/Base) system encapsulation Scans of 50x50 measurements each have been performed for different angles to ensure the geometrical consistency of the setup (PMT plane parallel to the fiber scaning plane): 0,90,180 and 360 deg. scans Also scans with different light intensities have been taken to test the uniformity in the linear response of each channel.

13. 2D Scans Different angles Different light I

14. To do list Let the new team get more experienced Complete a final version of the fine scans (Motor lost steps, etc…). Understand any the level of saturation of the signal Single photo-electron measurement using a 2-stage amplifier board (work in progress)