TileHit class

TileHit class is used to store visible energy deposited in active part of the Tile calorimeter in Geant4 simulation. Active part of the TileCal is scintillator and therefore Birk saturation law is applied to every Geant4 hit before adding this hit energy to total energy in TileHit

There are few differences between TileHit and LArHit classes:

1) One TileCal cell is read out by two PMTs and TileHit contains total energy visible by one PMT in a cell, or, roughly speaking only "half" of cell energy. Identifier stored in TileHit is a PMT identifier, which is built from cell identifier (e.g. 5/2/-1/62/12/1 ) with one extra field added at the end, namely PMT index (0 or 1). For details, see TileID.h class in Calorimeter/CaloIdentifier package

2) To have possibility to study signal pulse shape, m_energy and m_time member variables are vectors, and m_energy[i] is the energy deposited at time m_time[i]. Granularity in time can be set at initialization time. If, for example this granularity is set to 5 ns, m_time will contain values 0,5,10,... and m_energy vector will contain deposited energy in 5 ns bins. For full ATLAS simulation the granularity is set to 5ns and for testbeam and cosmic simulation granularity is usually set to 1ns. Time for testbeam and cosmic simulation stored in TileHit might be rather big (>100ns), but it is corrected by global event time in TileHitVecToCnt algorithm from TileSimAlgs package and hits which are used in TileDigitsMaker have time close to zero (within [-100ns,100ns] window)

TileHitVector class

TileHitVector is a typedef of AthenaHitsVector<TileHit> and it is used to persistify TileHits