Used to detect simultaneous events in GM tubes.
The box's output sends an impulse to an external counter, when two (or optionally three) of the inputs receive an impulse simultaneously (i.e. within 1 microsecond).
This allows you, for instance, to detect the gamma cascade in the decay of Co-60 or the fact that the annihilation quanta from Na-22 are radiated at 180° to each other.
The coincidence box is also used in the study of cosmic radiation.
It connects to two or three single GM tubes. The output impulses are registered by a GM counter 513600, counter 200250 or via a Pasco digital adapter PS-2159.
Comprehensive instructions included.