Signal readout from scintillating fiber by using multianode photomultiplier tubes

The authors studied the feasibility of using the multianode photomultiplier tube (MAPMT) in reading out the signals of minimum ionizing particles and the early development of electromagnetic showers in a Pb/scintillating fiber calorimeter. Measurements have been made on the characteristics of the scintillating fiber KURARAY SCSF-81 1 mm φ and on the properties of the Hamamatsu R3384 M246DX MAPMT. The spatial distribution of the anode response, effects of a magnetic field on the cross talk and the pulse height of the anode signals of the MAPMT were investigated. It was found that the magnetic field decreases the cross talk and increases the pulse heights significantly. It was confirmed that a magnetic field applied to the MAPMT is very useful for decreasing the cross talk and increasing the pulse heights of the illuminated anode segment. It was rather difficult to clearly separate the m.i.p. signals from the noise and to read out the early shower development due to the low S/N ratio