The E864 lead-scintillating fiber hadronic calorimeter

A large hadronic lead scintillating fiber calorimeter has been built and integrated into the AGS experiment E864 [C. Pruneau et al., E864 Collaboration, Proc. 6th Internat. Conf, on Calorimetry in High Energy Physics, 1996, Frascati, Italy; F. Rotondo et al, E864 Collaboration, Proc. Quark Matter 96, Heidelberg, Germany, 20 May 1996] spectrometer to provide an independent measurement of the mass of particles produced in heavy ion collisions. The "spaghetti-type" calorimeter design and construction techniques are described in detail. Results from a prototype and the full implementation of the calorimeter are reported. The hadronic energy resolution of the calorimeter is found to be delta E/E = 0.035(+/-0.005) + 0.344(+/-0.008)/root E/GeV, in very good agreement with a FLUKA calculation. The hadronic time resolution is measured to be better than 400 ps. The combined calorimeter energy and time signals provide for a mass determination with good resolution. The mass resolution scales as delta m/m = 0.026 + 0.347/root E(GeV) for velocities v/c < 0.98. (C) 1998 Published by Elsevier Science B.V. All rights reserved.