The CDF plug upgrade electromagnetic calorimeter: test beam results

Abstract The CDF Plug Upgrade calorimeter, which fully exploits the tile–fiber technique, was tested at the Fermilab meson beamline. The calorimeter was exposed to positron, positively charged pion and positive muon beams with energies in the range of 5– 230 GeV . The energy resolution of the electromagnetic calorimeter to the positron beam is consistent with the design value of 16%/ E ⊕1% , where E is the energy in units of GeV and ⊕ represents sum in quadrature. The non-linearity for positrons is studied in an energy range of 11– 181 GeV . It is important to incorporate the response of the preshower detector, the first layer of the electromagnetic calorimeter which is readout separately, into that of the calorimeter to reduce the non-linearity to 1% or less. The energy scale is about 1.46 pC / GeV with HAMAMATSU R4125 operated typically at a gain of 2.5×104. The response non-uniformity over the surface of a tower of the electromagnetic calorimeter is found to be about 2% with 57 GeV positrons. Studies of several detailed detector characteristics are also presented