The integer column named NDET contains the sequence number for the detector sub-table. Each detector channel has its own row in this sub-table. For multichannel instruments that devote one detector to each passband, these rows can be considered a natural continuation of the rows of the passband sub-table. In this case, the NBAND and NDET columns should have the same values within each row.
The A*16 column named DETNAME is optional, and is provided only for the user's convenience. As its name indicates, it can hold a character string naming the detector.