A high resolution calorimeter has been built for CHORUS, an experiment
which searches for nu(mu) --> nu(tau) oscillation in the CERN neutrin
o beam. Aim of the calorimeter is to measure the energy and direction
of hadronic showers produced in interactions of the neutrinos in a nuc
lear emulsion target and to track through-going muons. It is a longitu
dinally segmented sampling device made of lead and scintillating fiber
s or strips. This detector has been exposed to beams of pions and elec
trons of defined momentum for calibration. The method used for energy
calibration and results on the calorimeter performance are reported.