Speaker
Summary
The CALICE Collaboration
This talk will present the operational experience with a
highly-granular analogue hadronic calorimeter (AHCAL) consisting of
7608 individual scintillator tiles readout via
Silicon-Photo-multipliers (SiPM). The calibration of each cell is
based on minimum ionizing particle signals for which a muon beam is
used in first approximation. The full calibration of a cell, though,
requires to account for the non-linearity introduced by the finite
number of pixels (1156) in the SiPM. The aspects of temperature and
voltage dependence of SiPM are addressed, and monitoring and
calibration procedures are discussed. Such procedures are essential
for the extrapolation of calibration factors over several days of data
taking with the calorimeter. For this purpose a versatile UV-LED light
distribution system was developed, capable of delivering light to all
tiles with intensity from a few photo-electrons to the saturation of the
SiPM. The procedures are tested using data collected with the AHCAL at
the CERN SPS test beam.
