The construction, testing and performance of a Pb/scintillator calorimeter with fiber optic readout built for relativistic heavy ion studies

Abstract

A Pb/scintillator sampling calorimeter covering the pseudorapidity interval of n=0.83 to 4.20 has been designed and constructed for Experiment 814 of Brookhaven National Laboratory. The calorimeter uses wavelength shifting optical fibers for readout. Such fibers allow the construction of a highly granular and longitudinally compact device. Longitudinally, the calorimeter has a depth of four interaction lengths divided into two electromagnetic sections and two hadronic sections of 0.4, 0.4, 1.6, and 1.6 interaction lengths, respectively. The calorimeter has been exposed to electrons, protons, pions and muons ranging in energy from 1.56-6.80 GeV/c. The response of the detector to these particles will be described. Analysis indicates that the calorimeter is nearly compensating with an electron to hadron ratio approaching unity. An electron energy resolution of [approximately] 25%[square root E] and a hadronic energy resolution of [approximately] 40%[square root E] has been measured. The performance of the calorimeter in the June 1990 E814 heavy ion has been studied. The response of the detector 14.6A GeV/c silicon and Pb, Cu and Al collisions was examined. The detector was used to study the event structure of these heavy ion collisions. Results from a search for non-statistical energy fluctuations produced in heavy ion collisions will be presented.