N is generally used to refer to a Neutron Plane. For example, N1 would refer to the first Neutron Plane. The Neutron Planes have 25
CMU detectors in each of planes 1, 2, 3, and 4. These start numbering at 2, and go to 26. Above them, on planes 1 and 3 are 4 and 5
GLA bars, respectively. In planes 5, 6, and 7 a different detector type is used, the
UVA bars. These go from 0 to 39, and have 5
GLA bars above them. In plane 7 several
UVA bars were disconnected. These changed durring the course of the experiment.
A useful schematic of the Neutron Detector
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