Test setup
The setup consisted of a scintillating foil, four scintillating fibers for defining a beam position, two scintillator bars, one read out by hybrid tubes, the other read out by conventional photomultipliers and a paddle for defining the beam (which You can see from the left to the right of the picture).
Time resolution of the scintillating foil
We used a BC 418 foil, which was 200 mu thick. The foil was read out by 2 inch photomultipliers Valvo XP 2083. The time resolution is in the order of 200 ps (Postscript 15 kByte).
Z resolution of the scintillator bar
The BC 408 scintillator (0.7 cm thick, 2.5 cm wide) was read out by Valvo XP 2971-01 photomultipliers. In the pictures one can see the energy loss for different particles, namely Carbon, Bor, Berylium and Helium (Postscript 1.3 MByte). The resolution for the Scintillator read out by hybrid tubes was slightly worse.
Time resolution of the scintillator bar
A simple walk correction was used with the time spectra, which improved the time resolution by 10%. The time resolution is better than 70 ps for Carbon (Postscript 38 kByte). Again the resolution of the scintillator read out by hybrid tubes was worse (200 ps). The rather poor behaviour of the hybrid tubes compared to standard photomultipliers with active bases during this experiment was due to non-optimal amplifiers, some noise on the cables and very small signals, which was not the case for the photomultipliers because of a higher amplification factor.