Definition of sets of photomultipliers for the tile hadron calorimeter of the ATLAS detector

In order to fulfil to technical and physical requirements, the photomultiplier blocks of the tile hadron calorimeter of ATLAS have to be classified in sets corresponding to different types of cells. This note presents the constraints that should be taken into account. On the basis of the characterisation of 500 tubes, it appears that the main parameter is the nominal high voltage of photomultipliers. Three sets have been defined: one for barrel like drawers and two for extended barrel ones. At the end, the filling of each drawer with photomultiplier blocks belonging to the different sets is discussed.