Recent advances in counter techniques: Cherenkov counter and scintillation counter

Several kinds of particle detectors can be seen in this picture of equipment being assembled for tests at CERN. In the right foreground is a gas Cherenkov counter of the focusing type, used to ensure that the spark chamber behind is triggered only by electrons. In between, some plastic scintillators can be seen, mounted vertically on top of their photomultipliers. On the extreme left a large liquid scintillation counter is awaiting positioning. In the centre foreground is the filling apparatus for the Cherenkov counters, while racks of control and counting equipment can be seen in the background.